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<journal-meta>
<journal-id journal-id-type="publisher-id">Front. Genet.</journal-id>
<journal-title>Frontiers in Genetics</journal-title>
<abbrev-journal-title abbrev-type="pubmed">Front. Genet.</abbrev-journal-title>
<issn pub-type="epub">1664-8021</issn>
<publisher>
<publisher-name>Frontiers Media S.A.</publisher-name>
</publisher>
</journal-meta>
<article-meta>
<article-id pub-id-type="publisher-id">1405453</article-id>
<article-id pub-id-type="doi">10.3389/fgene.2024.1405453</article-id>
<article-categories>
<subj-group subj-group-type="heading">
<subject>Genetics</subject>
<subj-group>
<subject>Review</subject>
</subj-group>
</subj-group>
</article-categories>
<title-group>
<article-title>The known and unknown about attention deficit hyperactivity disorder (ADHD) genetics: a special emphasis on Arab population</article-title>
<alt-title alt-title-type="left-running-head">Mahrous et al.</alt-title>
<alt-title alt-title-type="right-running-head">
<ext-link ext-link-type="uri" xlink:href="https://doi.org/10.3389/fgene.2024.1405453">10.3389/fgene.2024.1405453</ext-link>
</alt-title>
</title-group>
<contrib-group>
<contrib contrib-type="author">
<name>
<surname>Mahrous</surname>
<given-names>Nahed N.</given-names>
</name>
<xref ref-type="aff" rid="aff1">
<sup>1</sup>
</xref>
<uri xlink:href="https://loop.frontiersin.org/people/2790944/overview"/>
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<role content-type="https://credit.niso.org/contributor-roles/Writing - review &#x26; editing/"/>
<role content-type="https://credit.niso.org/contributor-roles/formal-analysis/"/>
<role content-type="https://credit.niso.org/contributor-roles/software/"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname>Albaqami</surname>
<given-names>Amirah</given-names>
</name>
<xref ref-type="aff" rid="aff2">
<sup>2</sup>
</xref>
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<contrib contrib-type="author">
<name>
<surname>Saleem</surname>
<given-names>Rimah A.</given-names>
</name>
<xref ref-type="aff" rid="aff3">
<sup>3</sup>
</xref>
<role content-type="https://credit.niso.org/contributor-roles/investigation/"/>
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<contrib contrib-type="author">
<name>
<surname>Khoja</surname>
<given-names>Basmah</given-names>
</name>
<xref ref-type="aff" rid="aff4">
<sup>4</sup>
</xref>
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<contrib contrib-type="author">
<name>
<surname>Khan</surname>
<given-names>Mohammed I.</given-names>
</name>
<xref ref-type="aff" rid="aff4">
<sup>4</sup>
</xref>
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<contrib contrib-type="author" corresp="yes">
<name>
<surname>Hawsawi</surname>
<given-names>Yousef M.</given-names>
</name>
<xref ref-type="aff" rid="aff3">
<sup>3</sup>
</xref>
<xref ref-type="aff" rid="aff4">
<sup>4</sup>
</xref>
<xref ref-type="corresp" rid="c001">&#x2a;</xref>
<uri xlink:href="https://loop.frontiersin.org/people/1192455/overview"/>
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<aff id="aff1">
<sup>1</sup>
<institution>Department of Biological Sciences</institution>, <institution>College of Science</institution>, <institution>University of Hafr Al-Batin</institution>, <addr-line>Hafr Al- Batin</addr-line>, <country>Saudi Arabia</country>
</aff>
<aff id="aff2">
<sup>2</sup>
<institution>Department of Clinical Laboratory Sciences</institution>, <institution>Turbah University College</institution>, <institution>Taif University</institution>, <addr-line>Taif</addr-line>, <country>Saudi Arabia</country>
</aff>
<aff id="aff3">
<sup>3</sup>
<institution>Department of Biochemistry and Molecular Medicine</institution>, <institution>College of Medicine</institution>, <institution>Al-Faisal University</institution>, <addr-line>Riyadh</addr-line>, <country>Saudi Arabia</country>
</aff>
<aff id="aff4">
<sup>4</sup>
<institution>Research Center</institution>, <institution>King Faisal Specialist Hospital and Research Center</institution>, <addr-line>Jeddah</addr-line>, <country>Saudi Arabia</country>
</aff>
<author-notes>
<fn fn-type="edited-by">
<p>
<bold>Edited by:</bold> <ext-link ext-link-type="uri" xlink:href="https://loop.frontiersin.org/people/562127/overview">J. Francis Borgio</ext-link>, Imam Abdulrahman Bin Faisal University, Saudi Arabia</p>
</fn>
<fn fn-type="edited-by">
<p>
<bold>Reviewed by:</bold> <ext-link ext-link-type="uri" xlink:href="https://loop.frontiersin.org/people/34557/overview">Juko Ando</ext-link>, Keio University, Japan</p>
<p>
<ext-link ext-link-type="uri" xlink:href="https://loop.frontiersin.org/people/1137178/overview">Cristina Skrypnyk</ext-link>, Arabian Gulf University, Bahrain</p>
</fn>
<corresp id="c001">&#x2a;Correspondence: Yousef M. Hawsawi, <email>hyousef@kfshrc.edu.sa</email>
</corresp>
</author-notes>
<pub-date pub-type="epub">
<day>06</day>
<month>08</month>
<year>2024</year>
</pub-date>
<pub-date pub-type="collection">
<year>2024</year>
</pub-date>
<volume>15</volume>
<elocation-id>1405453</elocation-id>
<history>
<date date-type="received">
<day>22</day>
<month>03</month>
<year>2024</year>
</date>
<date date-type="accepted">
<day>15</day>
<month>07</month>
<year>2024</year>
</date>
</history>
<permissions>
<copyright-statement>Copyright &#xa9; 2024 Mahrous, Albaqami, Saleem, Khoja, Khan and Hawsawi.</copyright-statement>
<copyright-year>2024</copyright-year>
<copyright-holder>Mahrous, Albaqami, Saleem, Khoja, Khan and Hawsawi</copyright-holder>
<license xlink:href="http://creativecommons.org/licenses/by/4.0/">
<p>This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.</p>
</license>
</permissions>
<abstract>
<p>Attention deficit hyperactivity disorder (ADHD) is a clinically and genetically heterogeneous neurodevelopmental syndrome characterized by behavioral appearances such as impulsivity, inattention, and hyperactivity. The prevalence of ADHD is high in childhood when compared to adults. ADHD has been significantly advanced by genetic research over the past 25&#xa0;years. However, it is logically conceivable that both genetic and/or non-genetic factors, such as postnatal environmental and social influences, are associated with ADHD phenotype in Arab populations. While genetic influences are strongly linked with the etiology of ADHD, it remains obscure how consanguinity which is an underlying factor for many genetic diseases, contributes to ADHD subtypes. Arabian Gulf Nations have one the highest rates of consanguineous marriages, and consanguinity plays an important contributing factor in many genetic diseases that exist in higher percentages in Arabian Gulf Nations. Therefore, the current review aims to shed light on the genetic variants associated with ADHD subtypes in Arabian Gulf nations and Saudi Arabia in particular. It also focuses on the symptoms and the diagnosis of ADHD before turning to the neuropsychological pathways and subgroups of ADHD. The impact of a consanguinity-based understanding of the ADHD subtype will help to understand the genetic variability of the Arabian Gulf population in comparison with the other parts of the world and will provide novel information to develop new avenues for future research in ADHD.</p>
</abstract>
<kwd-group>
<kwd>ADHD</kwd>
<kwd>ASD</kwd>
<kwd>consanguinity</kwd>
<kwd>genetic variants</kwd>
<kwd>neurodevelopmental disorders</kwd>
<kwd>learning disorder</kwd>
</kwd-group>
<contract-sponsor id="cn001">King Salman Center for Disability Research<named-content content-type="fundref-id">10.13039/501100019345</named-content>
</contract-sponsor>
<custom-meta-wrap>
<custom-meta>
<meta-name>section-at-acceptance</meta-name>
<meta-value>Behavioral and Psychiatric Genetics</meta-value>
</custom-meta>
</custom-meta-wrap>
</article-meta>
</front>
<body>
<sec id="s1">
<title>1 Introduction</title>
<p>Attention-deficit hyperactivity disorder (ADHD) is a common clinically and genetically transmitted neurological condition that affects an individual&#x2019;s behavior (<xref ref-type="bibr" rid="B11">American Academy of Pediatrics, 2001</xref>). Symptoms of ADHD such as mood and anxiety disorders, conduct disorder, and oppositional defiant disorder are usually noticed at an early age of childhood and are increasingly recognized in adulthood (<xref ref-type="bibr" rid="B24">Biederman et al., 2006</xref>). It has been reported that among 3%&#x2013;10% of those diagnosed with ADHD disorder in their childhood, and 6% of the overall population continue to develop noticeable ADHD conditions (<xref ref-type="bibr" rid="B118">Wender et al., 2001</xref>). The concept of ADHD as a clinical condition has changed over the 20th century until the onset of the twin and family studies (<xref ref-type="bibr" rid="B55">Foreman, 2006</xref>). The historical descriptions associated with ADHD ranged from early brain damage &#x201c;neurodevelopmental disorders&#x201d; to the indirect contribution of genetic and environmental factors (<xref ref-type="bibr" rid="B106">Sonuga-Barke et al., 2023</xref>). Nevertheless, many descriptions are consistent with the modern diagnostic strategies for ADHD.</p>
<p>In 1798, a Scottish physician named Sir Alexander Crichton was the earliest to reveal that the incapacity of attending may be innate or due to unnatural nervous sensibility (<xref ref-type="bibr" rid="B75">Lange et al., 2010</xref>). Crichton saw numerous examples of insanity in his therapeutic practice and had a growing interest in mental illness. Fidgety Philip (Heinrich Hoffmann), a German physician, in 1840s was the first to write allegory stories for children with ADHD (<xref ref-type="bibr" rid="B11">American Academy of Pediatrics, 2001</xref>). In the 1990s century, the description of the characteristic features of an individual with ADHD became the focus of several scientists (<xref ref-type="bibr" rid="B111">Thome and Jacobs, 2004</xref>). Geroge Still, a British pediatrician, in 1902 described an abnormal defect of moral control in children and found that some could not control their behavior in a typical way, but were still intelligent (<xref ref-type="bibr" rid="B75">Lange et al., 2010</xref>). In 1919, ADHD was blamed on brain damage, and numerous words were associated with the disorder, such as impulsive, inattentive, hyperactive, and short attention span (<xref ref-type="bibr" rid="B29">Burd and Kerbeshian, 1988</xref>). Medications for symptoms were discovered during the 1930s, and research on ADHD in both children and adults continued throughout the 19th and 20th centuries as a worldwide interest (<xref ref-type="bibr" rid="B1">Abdelnour et al., 2022</xref>).</p>
<p>Attention deficit hyperactivity disorder accounts for over 5% of frequent disorders within child and adolescent psychiatry (<xref ref-type="bibr" rid="B47">Drechsler et al., 2020</xref>). Physicians still struggle with diagnosis and treatment despite the enormous volume of research, more than 20,000 publications have been mentioned in PubMed during the past 10&#xa0;years. Due to its heterogeneous nature, ADHD can present in opposite forms with frequent and variable comorbidities (<xref ref-type="bibr" rid="B116">Wahlstedt et al., 2009</xref>). Additionally, there is an overlap between the symptoms of ADHD and other diseases, such as autism spectrum disorder (ASD), major depressive disorder, bipolar disorder, and schizophrenia, which may or may not show up on a clinical assessment (<xref ref-type="bibr" rid="B87">Morimoto et al., 2021</xref>). Biomarkers or other objective criteria that could result in an automatic algorithm for the reliable identification of ADHD in an individual within clinical practice are currently absent, despite the fact that the disorder&#x2019;s neurological and genetic foundations are undeniable.</p>
</sec>
<sec id="s2">
<title>2 Symptoms of ADHD</title>
<p>The characteristic features of individuals with ADHD include hyperactivity, inattentiveness, and impulsiveness, which lead to impairments in daily living (<xref ref-type="fig" rid="F1">Figure 1</xref>). Characterization of ADHD based on features is ensured by looking at a lack of moral control through inattentive and hyperactive-impulsive symptoms or a mix of both symptoms (<xref ref-type="bibr" rid="B88">Muller et al., 2011</xref>). Inattentive symptoms include trouble focusing, finishing tasks, following instructions, memories not always easy to recall, careless mistakes, and losing belongings (<xref ref-type="bibr" rid="B88">Muller et al., 2011</xref>). The hyperactive-impulsive symptoms include excessive talking and physical movement, interrupting conversations, answering before the question has been finished, dangerous behavior, choosing a smaller reward now rather than a larger reward later, finding boredom intolerable, and looking for stimulation. Some people have combined symptoms of both inattentive and hyperactive-impulsive symptoms (<xref ref-type="bibr" rid="B16">American Psychiatric Association, 1987</xref>).</p>
<fig id="F1" position="float">
<label>FIGURE 1</label>
<caption>
<p>Symptoms of ADHD: weakness and strength. Each type of ADHD is tied to one or more characteristics: inattention and hyperactive-impulsive behavior.</p>
</caption>
<graphic xlink:href="fgene-15-1405453-g001.tif"/>
</fig>
<p>Brain development and functions are achieved by expressing multiple genes distributed in four brain regions: frontal cortex, cerebellum, parietal lobe, and basal ganglion (<xref ref-type="table" rid="T1">Table 1</xref>). These genes are essential in regulating systemic sympathetic activity and contribute to the behaviors associated with dopamine levels. Normal brains and brains with ADHD develop in the same manner. However, the brain with ADHD develops more slowly overall, particularly in the frontal lobes that help with impulse control and concentration (<xref ref-type="fig" rid="F2">Figure 2</xref>). As a result, neurodevelopmental disorders including ADHD may not mature to the same degree as a normal brain, though, depending on how severe the symptoms are (<xref ref-type="bibr" rid="B58">Gehricke et al., 2017</xref>). In fact, people with childhood ADHD diagnoses had a smaller overall brain capacity than adults without such a diagnosis, according to neuroscientists (<xref ref-type="bibr" rid="B31">Castellanos et al., 2002</xref>). In the areas of their brains impacted by ADHD, there was greater cortical thinning and less cortical thickness in the outer layer (<xref ref-type="bibr" rid="B74">Konrad et al., 2012</xref>). This essentially indicates that there were fewer brain cells in these regions in these people. Normal brains may produce brain cells more quickly than brains with ADHD, which could be one explanation for this. Therefore, before cortical thinning begins, those people have a higher initial level of grey matter. In addition, the brain with ADHD has a lower level of dopamine, which helps control the brain&#x2019;s reward and regulates movement and emotional responses, in comparison with the normal brain (<xref ref-type="fig" rid="F3">Figure 3</xref>). As a result, the ADHD brain cannot stay motivated and experiences functional changes and weak connectivity. In general, the structure, chemistry, and function of the ADHD brain differ from those of the non-ADHD brain.</p>
<table-wrap id="T1" position="float">
<label>TABLE 1</label>
<caption>
<p>A representation of a collective of genes that encode for primary altered structural and functional brain changes within the five brain regions that were found to be correlated with the mechanism of actions found in attention-deficit hyperactivity disorder (ADHD).</p>
</caption>
<table>
<thead valign="top">
<tr>
<th align="center" style="background-color:#8497B0">Risk Genes</th>
<th align="center" style="background-color:#BFBFBF">Gene Function</th>
<th align="center" style="background-color:#ED7D31">Frontal Cortex</th>
<th align="center" style="background-color:#92D050">Occipital</th>
<th align="center" style="background-color:#CC99FF">Cerebellum</th>
<th align="center" style="background-color:#FFFF66">Parietal Lobe</th>
<th align="center" style="background-color:#61E1FF">Basal Ganglion</th>
</tr>
</thead>
<tbody valign="top">
<tr>
<td align="center" style="background-color:#c2d6d6">ADRA2A</td>
<td align="center" style="background-color:#f0f5f5">Alpha-2A adrenergic receptor, regulates systemic sympathetic activity and cardiovascular responses.</td>
<td align="center" style="background-color:#ffd1b3">&#x221a;</td>
<td align="center" style="background-color:#99ff99"/>
<td align="center" style="background-color:#f7e6ff"/>
<td align="center" style="background-color:#ffffb3"/>
<td align="center" style="background-color:#ccfff2"/>
</tr>
<tr>
<td align="center" style="background-color:#c2d6d6">COMT</td>
<td align="center" style="background-color:#f0f5f5">Catechol-O-methyltransferase, involves in the inactivation of the catecholamine neurotransmitters (dopamine, epinephrine, and norepinephrine).</td>
<td align="center" style="background-color:#ffd1b3"/>
<td align="center" style="background-color:#99ff99"/>
<td align="center" style="background-color:#f7e6ff">&#x221a;</td>
<td align="center" style="background-color:#ffffb3"/>
<td align="center" style="background-color:#ccfff2">&#x221a;</td>
</tr>
<tr>
<td align="center" style="background-color:#c2d6d6">DRD1</td>
<td align="center" style="background-color:#f0f5f5">Dopamine receptor D1, regulates the memory, learning, and the growth of neurons and mediates some behaviors.</td>
<td align="center" style="background-color:#ffd1b3">&#x221a;</td>
<td align="center" style="background-color:#99ff99"/>
<td align="center" style="background-color:#f7e6ff">&#x221a;</td>
<td align="center" style="background-color:#ffffb3">&#x221a;</td>
<td align="center" style="background-color:#ccfff2">&#x221a;</td>
</tr>
<tr>
<td align="center" style="background-color:#c2d6d6">DRD4</td>
<td align="center" style="background-color:#f0f5f5">Dopamine receptor D4, regulates the dopaminergic system and contributes to the behaviors connected with dopamine levels.</td>
<td align="center" style="background-color:#ffd1b3">&#x221a;</td>
<td align="center" style="background-color:#99ff99"/>
<td align="center" style="background-color:#f7e6ff">&#x221a;</td>
<td align="center" style="background-color:#ffffb3">&#x221a;</td>
<td align="center" style="background-color:#ccfff2">&#x221a;</td>
</tr>
<tr>
<td align="center" style="background-color:#c2d6d6">HTR1B</td>
<td align="center" style="background-color:#f0f5f5">Encodes the 5-hydroxytryptamine receptor 1B, its function differs upon its brain location.</td>
<td align="center" style="background-color:#ffd1b3">&#x221a;</td>
<td align="center" style="background-color:#99ff99"/>
<td align="center" style="background-color:#f7e6ff"/>
<td align="center" style="background-color:#ffffb3"/>
<td align="center" style="background-color:#ccfff2"/>
</tr>
<tr>
<td align="center" style="background-color:#c2d6d6">MAOA</td>
<td align="center" style="background-color:#f0f5f5">Monoamine oxidase A, regulator for normal brain function.</td>
<td align="center" style="background-color:#ffd1b3">&#x221a;</td>
<td align="center" style="background-color:#99ff99"/>
<td align="center" style="background-color:#f7e6ff"/>
<td align="center" style="background-color:#ffffb3">&#x221a;</td>
<td align="center" style="background-color:#ccfff2"/>
</tr>
<tr>
<td align="center" style="background-color:#c2d6d6">NET1</td>
<td align="center" style="background-color:#f0f5f5">Neuroepithelial cell-transforming gene 1, regulate cell signaling.</td>
<td align="center" style="background-color:#ffd1b3">&#x221a;</td>
<td align="center" style="background-color:#99ff99"/>
<td align="center" style="background-color:#f7e6ff"/>
<td align="center" style="background-color:#ffffb3">&#x221a;</td>
<td align="center" style="background-color:#ccfff2"/>
</tr>
<tr>
<td align="center" style="background-color:#c2d6d6">NR3C1</td>
<td align="center" style="background-color:#f0f5f5">Glucocorticoid receptor, regulates genes controlling the development, metabolism and immune response.</td>
<td align="center" style="background-color:#ffd1b3"/>
<td align="center" style="background-color:#99ff99"/>
<td align="center" style="background-color:#f7e6ff">&#x221a;</td>
<td align="center" style="background-color:#ffffb3"/>
<td align="center" style="background-color:#ccfff2"/>
</tr>
<tr>
<td align="center" style="background-color:#c2d6d6">SLC6A3</td>
<td align="center" style="background-color:#f0f5f5">Encodes sodium-dependent dopamine transporter, provides instructions for making dopamine transporter.</td>
<td align="center" style="background-color:#ffd1b3">&#x221a;</td>
<td align="center" style="background-color:#99ff99"/>
<td align="center" style="background-color:#f7e6ff"/>
<td align="center" style="background-color:#ffffb3">&#x221a;</td>
<td align="center" style="background-color:#ccfff2">&#x221a;</td>
</tr>
<tr>
<td align="center" style="background-color:#c2d6d6">SLC6A4</td>
<td align="center" style="background-color:#f0f5f5">Encodes 5-HTTLPR, the sodium-dependent serotonin transporter, responsible for serotonin reuptake into the presynaptic neuron.</td>
<td align="center" style="background-color:#ffd1b3">&#x221a;</td>
<td align="center" style="background-color:#99ff99"/>
<td align="center" style="background-color:#f7e6ff">&#x221a;</td>
<td align="center" style="background-color:#ffffb3"/>
<td align="center" style="background-color:#ccfff2">&#x221a;</td>
</tr>
</tbody>
</table>
</table-wrap>
<fig id="F2" position="float">
<label>FIGURE 2</label>
<caption>
<p>Schematic representation of normal brain and brain with ADHD. Brain consists of five main regions: prefrontal cortex, occipital lobe, cerebellum, the basal ganglia, and parietal lobe. These regions control and regulate several functions such as: inhibition, memory, planning and organization, motivation, processing speed, inattention and impulsivity. Brain development in individual with ADHD is smaller in the prefrontal cortex, and cerebellum regions as compare to a normal brain. Also, ADHD has been linked to deficits in the functioning of the prefrontal cortex, the basal ganglia, cerebellum and parietal lobe.</p>
</caption>
<graphic xlink:href="fgene-15-1405453-g002.tif"/>
</fig>
<fig id="F3" position="float">
<label>FIGURE 3</label>
<caption>
<p>Schematic representation of dopamine level and transmission in normal brain and brain with ADHD. Dopaminergic neuron is located in the midbrain and control various functions. The level of dopamine in normal brain is higher than the level in brain with ADHD. Dopamine level contributes to the symptoms of inattention, hyperactivity, and impulsiveness in ADHD.</p>
</caption>
<graphic xlink:href="fgene-15-1405453-g003.tif"/>
</fig>
</sec>
<sec id="s3">
<title>3 Diagnosis of ADHD</title>
<p>Attention deficit hyperactivity disorder is considered a major public health problem (<xref ref-type="bibr" rid="B54">Ferguson, 2000</xref>) as it causes serious impairment at school, home, and society (<xref ref-type="bibr" rid="B16">American Psychiatric Association, 1987</xref>). Therefore, to diagnose ADHD, impairment in school performance and daily life is assessed by using a symptoms inventory questionnaire for ADHD described in the Diagnostic and Statistical Manual of Mental Disorders (DSM-5) or the International Statistical Classification of Diseases and Related Health Problems (ICD-10) (<xref ref-type="bibr" rid="B22">Bell, 1994</xref>; <xref ref-type="bibr" rid="B92">Organization, 2004</xref>) (<xref ref-type="fig" rid="F4">Figure 4</xref>). Children diagnosed with ADHD presented with 6&#x2013;9 symptoms by the age of 12 for (DSM-5) or before the age of 7 for (ICD-10). Symptoms should have lasted for more than 6 months (<xref ref-type="bibr" rid="B22">Bell, 1994</xref>). The assessment must be carried out by a psychiatrist, pediatrician, or ADHD specialist. A full developmental and psychosocial history, and physical examination, alongside family and school reports, are essential to diagnose ADHD (<xref ref-type="bibr" rid="B92">Organization, 2004</xref>).</p>
<fig id="F4" position="float">
<label>FIGURE 4</label>
<caption>
<p>An approach to the evaluation and the diagnosis of ADHD in children and adults.</p>
</caption>
<graphic xlink:href="fgene-15-1405453-g004.tif"/>
</fig>
<p>Current available ADHD objective assessment includes neuropsychological tests, neuroimaging, and electroencephalography (EEG). Research has shown that individuals with ADHD exhibit distinct genetic anomalies compared to those without the disorder. Unfortunately, there is insufficient evidence on the use of these tests to establish ADHD diagnosis (<xref ref-type="bibr" rid="B67">Kemper et al., 2018</xref>). Besides, there is no genetic testing in use to diagnose ADHD regardless of its high heritability (approximately 80%) (<xref ref-type="bibr" rid="B109">Thapar, 2018</xref>). However, numerous studies have utilized different types of genetic testing to understand and explore the genetic involvement in ADHD. Gene-wide association studies (GWAS) of single nucleotide polymorphisms (SNPs) and copy number variants (CNVs), next-generation sequencing (NGS), and single nucleotide variants (SNVs) for example, have illustrated the genetic contribution in the ADHD etiology (<xref ref-type="bibr" rid="B62">Hawi et al., 2015</xref>; <xref ref-type="bibr" rid="B81">Lima Lde et al., 2016</xref>; <xref ref-type="bibr" rid="B60">Grimm et al., 2018</xref>). The array of comparative genomic hybridization (aCGH) genetic testing has also helped identify the associated CNVs in many neuropsychiatric disorders including intellectual disability (ID), ASD, and ADHD (<xref ref-type="bibr" rid="B18">Baccarin et al., 2020</xref>). In this context, CNVs in multiple chromosomal regions have been linked with ADHD (5p13, 14q12, and 17p11) (<xref ref-type="bibr" rid="B13">Arcos-Burgos et al., 2004</xref>; <xref ref-type="bibr" rid="B90">Ogdie et al., 2006</xref>). In addition, Demontis et al. (2019) have shown many genetic variants correlated with ADHD on chromosomes 1&#x2013;5, 7&#x2013;8, 10, 12, and 15&#x2013;16 (<xref ref-type="bibr" rid="B45">Demontis et al., 2019</xref>).</p>
<p>Given that, it is important to know that ADHD symptoms can overlap with other coexisting conditions, such as the development of substance use, motor control, conduct, language, learning, and mood disorders in children and bipolar, obsessive-compulsive, and personality disorders in adults (<xref ref-type="bibr" rid="B26">Bonati et al., 2018</xref>). While severe attention, hyperactivity, and impulsive impairments are hallmarks of ADHD, the disorder sometimes coexists with other neurological conditions, including ASD (<xref ref-type="bibr" rid="B46">Dougnon and Matsui, 2022</xref>). Along with repetitive and limited behavior and interests, ASD is linked to poor communication and social interaction abilities. Therefore, differentiation between these disorders during diagnosis is required.</p>
<p>Attention-deficit hyperactivity disorder is associated with a variety of neuropsychological (NP) characteristics and underlying neurobiological pathways (<xref ref-type="bibr" rid="B41">Curatolo et al., 2010</xref>). An early dual pathway model distinguished between an inhibitory/executive function pathway and a motivational/delay aversion pathway (also referred to as the &#x201c;cool&#x201d; and &#x201c;hot&#x201d; executive function pathways in later publications). These pathways are related to different neurobiological networks. Twenty-five years ago, ADHD was diagnosed as a disorder of inhibitory self-control (<xref ref-type="bibr" rid="B33">Castellanos and Tannock, 2002</xref>; <xref ref-type="bibr" rid="B32">Castellanos et al., 2006</xref>). Although other routes, such as time processing, have been introduced, it is challenging to pinpoint the exact number of pathways that could exist. For example, Coghill and colleagues (2014) distinguished six cognitive characteristics in children with ADHD, including working memory, inhibition, delay aversion, decision-making, timing, and response time variability, using data from seven subtests of the computerized Cambridge NP test battery (<xref ref-type="bibr" rid="B38">Coghill et al., 2014</xref>). Other empirical research have distinguished between three (<xref ref-type="bibr" rid="B59">Gomez et al., 2014</xref>) or four (<xref ref-type="bibr" rid="B48">Fair et al., 2012</xref>) NP profile groups, which all included children with ADHD as well as typically developing (TD) children, differing in severity but not in the type of profile. These studies used latent profile or cluster analysis of NP tasks in large ADHD samples. However, in the process of looking for subgroups, some additional empirical research found performance profiles that were specific to ADHD (poor cognitive control (<xref ref-type="bibr" rid="B113">van Hulst et al., 2015</xref>), with attentional lapses and fast processing speed (<xref ref-type="bibr" rid="B23">Bergwerff et al., 2019</xref>), among other profiles that were shared with TD controls). Divergent subgrouping outcomes can, of course, also be attributed to different compilations of domains that have been studied, which limits the comparability of these investigations.</p>
<sec id="s3-1">
<title>3.1 Animal models of ADHD</title>
<p>Characteristics of ADHD are based upon the presence of three main criteria: attention, hyperactivity, and impulsiveness, which must be present before the age of 7. Identifying biological markers to describe the core disorder of ADHD may help to develop new diagnostic and treatment strategies. Several animal models of ADHD have been proposed to provide insight for this purpose although they cannot accurately reflect human psychiatric condition (<xref ref-type="bibr" rid="B105">Sontag et al., 2010</xref>; <xref ref-type="bibr" rid="B99">Russell, 2011</xref>).</p>
<p>Animal models should meet the necessary validation criteria: 1) face validity, which includes the three core symptoms of ADHD, etiology, treatment, and physiological basis of the modeled disease; 2) construct validity, which conforms to pathophysiological mechanisms; and 3) predictive validity, which is the ability to predict unknown aspects of the ADHD (<xref ref-type="bibr" rid="B114">Viggiano et al., 2004</xref>; <xref ref-type="bibr" rid="B105">Sontag et al., 2010</xref>; <xref ref-type="bibr" rid="B99">Russell, 2011</xref>). Various animal models with distinctly different neural defects (rats, mice, and monkeys) have been proposed to reflect the heterogeneous nature of ADHD, yet none can ensure which model best represents neither the disorder nor its subtypes. These models can be divided into: 1) genetic/trans-genetic, and 2) pharmacological animal models (<xref ref-type="table" rid="T2">Table 2</xref>) (<xref ref-type="bibr" rid="B69">Kim et al., 2024</xref>).</p>
<table-wrap id="T2" position="float">
<label>TABLE 2</label>
<caption>
<p>Propose animal models in attention-deficit hyperactivity disorder (ADHD) research (<xref ref-type="bibr" rid="B96">Regan et al., 2022</xref>; <xref ref-type="bibr" rid="B69">Kim et al., 2024</xref>).</p>
</caption>
<table>
<thead valign="top">
<tr>
<th align="center">Genetic/Trans-genetic animal models</th>
<th align="center">Pharmacological animal models</th>
</tr>
</thead>
<tbody valign="top">
<tr>
<td align="left">Spontaneously hypertensive rat (SHR)<break/>&#x2022; Inbred strain derived from WKY rat<break/>&#x2022; Hyperactivity, impulsivity and inattention</td>
<td align="left">Neonatal 6-hydroxydopamine rats</td>
</tr>
<tr>
<td align="left">Naples high-excitability rats<break/>&#x2022; Lower expression of DAD1 transcripts in NHE<break/>&#x2022; 26 mRNAs expressed in the prefrontal cortex<break/>&#x2022; Hyperactivity and inattention</td>
<td align="left">Neonatal hypoxia in rats</td>
</tr>
<tr>
<td rowspan="5" align="left">Acallosal mice<break/>&#x2022; Hyperactivity and impulsivity</td>
<td align="left">Developmental cerebellar stunting in rats</td>
</tr>
<tr>
<td align="left">Metylazoxymethanol (MAM)</td>
</tr>
<tr>
<td align="left">Amphetamine</td>
</tr>
<tr>
<td align="left">Alpha-difluoromethylornithine (DFMO)</td>
</tr>
<tr>
<td align="left">Dexamethasone</td>
</tr>
<tr>
<td align="left">Alpha synuclein lacking mice<break/>&#x2022; Lack of alpha or/and gamma synuclein<break/>&#x2022; Hyperactivity</td>
<td rowspan="4" align="left">Maternally stressed mice</td>
</tr>
<tr>
<td align="left">Dopamine-transporter knockout mouse (DAT-KO)<break/>&#x2022; Mouse lacks the DA transporter (DAT) gene</td>
</tr>
<tr>
<td align="left">Coloboma mutant mouse<break/>&#x2022; Disruption in about 20 genes (e.g., SNAP)<break/>&#x2022; Hyperactivity, impulsivity and inattention</td>
</tr>
<tr>
<td align="left">Thyroid hormone receptor (TR)-beta (1) transgenic mouse<break/>&#x2022; Mouse carries a mutant human TR&#x3b2;1 gene, which was derived from a patient diagnosed to suffer from a resistance to thyroid hormone (<xref ref-type="bibr" rid="B28">Buitelaar et al., 2022</xref>) syndrome<break/>&#x2022; Hyperactivity, impulsivity and inattention</td>
</tr>
</tbody>
</table>
</table-wrap>
<p>Of all the rodent models, research demonstrated that spontaneously hypertensive rat (SHR), a genetic model derived from Wistar-Kyoto (WKY) rats, fulfills many of the validation criteria for ADHD. Nevertheless, it shows several characteristic features of the disorder including inattention, impulsivity, and hyperactivity when compared to normotensive, WKY rats from various tests (<xref ref-type="bibr" rid="B96">Regan et al., 2022</xref>). Additionally, SHR shows neuropathological changes similar to those observed in patients with ADHD when compared with the WKY (e.g., smaller prefrontal cortex and hippocampus and fewer neurons). Several studies have reported developmental changes in the expression of dopamine transporter gene (DAT) in specific regions of the brain and dopamine uptake and utilization (<xref ref-type="bibr" rid="B39">Cook et al., 1995</xref>; <xref ref-type="bibr" rid="B72">Kirley et al., 2003</xref>; <xref ref-type="bibr" rid="B25">Bobb et al., 2005</xref>). Decreased expression of DAT4 in the prefrontal cortex and increased density of DAT1 and DAT5 in the neostriatum were observed in young male SHR (<xref ref-type="bibr" rid="B80">Li et al., 2007</xref>). However, transgenic animals such as Naples high excitability rat (<xref ref-type="bibr" rid="B70">Kim et al., 2020</xref>) performers promise to be useful models for investigating novel genes associated with ADHD <italic>in vivo</italic>. Other proposed animal models focus on the less important symptom of hyperactivity and may offer an opportunity to explore the role of dopamine in brain illness and assess new ADHD treatments.</p>
</sec>
</sec>
<sec id="s4">
<title>4 Genetics and heritability of ADHD</title>
<p>Early molecular genetic research on ADHD aimed to link the disorder with genes that had prior plausibility in its development. Given that medications addressing ADHD primarily act on dopaminergic or noradrenergic transmission, many studies focused on investigating &#x201c;candidate genes&#x201d; within these pathways. Variants in genes related to neurotransmitter regulation, such as dopamine (<xref ref-type="bibr" rid="B43">Del Campo et al., 2011</xref>) and norepinephrine (<xref ref-type="bibr" rid="B15">Arnsten and Pliszka, 2011</xref>) pathways, appear to play a significant role. Furthermore, understanding the gene functions associated with altered brain function in neurodevelopmental disorders can unravel the biological pathways involved in ADHD.</p>
<p>The heritability of ADHD is between 75% and 90% based on twin and family studies. Recent studies have identified a strong hereditary component in ADHD, suggesting that genetics may account for up to 70%&#x2013;80% of the variance in ADHD risk (<xref ref-type="bibr" rid="B109">Thapar, 2018</xref>). Multiple genes are implicated, each exerting a modest effect (<xref ref-type="bibr" rid="B51">Faraone and Larsson, 2019</xref>). Furthermore, it was discovered that the heritability of the inattentive and hyperactive-impulsive components of ADHD was comparable in males and females (<xref ref-type="bibr" rid="B51">Faraone and Larsson, 2019</xref>). Understanding the genetic underpinnings of ADHD is a complex and evolving field of research. This review delves into the intricate web of genetic factors that contribute to the development and manifestation of ADHD, shedding light on the interplay between genes and this neurodevelopmental disorder. It has recently been demonstrated that there are heritable components linked to ADHD in the structural and functional brain connections evaluated in families with children diagnosed with ADHD (<xref ref-type="bibr" rid="B108">Sudre et al., 2017</xref>). In a similar vein, it was discovered that there was a high heritability of the event-related potentials (ERPs) generated in a Go/No-Go test that measured reaction inhibition, which is known to be changed in ADHD (<xref ref-type="bibr" rid="B12">Anokhin et al., 2017</xref>).</p>
<p>Twin and family studies provide valuable insights into the genetic basis of traits and diseases. The key idea in twin studies is to compare the within-pair similarities of Monozygotic (MZ) twins to those of Dizygotic twins (DZ). If a trait or characteristic has a stronger correlation within MZ pairs compared to DZ pairs, it suggests a significant genetic influence on that trait. On the other hand, if the resemblance is similar between MZ and DZ pairs, it implies a greater role for environmental factors. Such studies also help researchers understand the mode of inheritance, estimate heritability, identify genetic markers, and unravel the interplay between genes and the environment. Furthermore, information gathered from family and twin studies is often used to design and interpret GWAS, which aims to identify specific genes associated with diseases.</p>
<p>A study with 894 individuals diagnosed with ADHD and 1,135 of their siblings, aged 5&#x2013;17&#xa0;years, uncovered a nine-fold increase in the likelihood of ADHD among the siblings of individuals with ADHD when compared to siblings in the control group (<xref ref-type="bibr" rid="B35">Chen et al., 2008</xref>). Another twin study conducted by Larsson et al. (2012) applied twin methods to investigate the extent to which ADHD is etiologically distinct from subthreshold variations in ADHD symptoms. Interestingly, when the extreme and subthreshold continuous ADHD characteristic symptoms were evaluated in the Swedish twins, a significant hereditary component was also discovered (<xref ref-type="bibr" rid="B76">Larsson et al., 2012</xref>). Family and twin studies have also contributed immensely in identifying and verifying genes that are associated with ADHD. A study by <xref ref-type="bibr" rid="B78">Lasky-Su et al. (2008)</xref> investigated 958 ADHD proband-parent trios by genotyping over 600,000 SNPs (<xref ref-type="bibr" rid="B70">Kim et al., 2020</xref>). Two novel variants were identified and are located in intronic regions of genes CDH13 and GFOD1. The CDH13 gene provides instructions for producing a calcium-dependent cell-cell adhesion protein crucial for influencing synaptic plasticity and neuronal development. Various genome-wide genetic methods, such as linkage analyses, association studies, and investigations into copy number variations, have identified connections between the CDH13 gene and diverse neurodevelopmental disorders. This suggests that alterations in CDH13 may contribute to the susceptibility or development of conditions impacting the nervous system during early development (<xref ref-type="bibr" rid="B98">Rivero et al., 2015</xref>). Another gene that was found to be significantly associated with the criteria is SLC9A9 (<xref ref-type="bibr" rid="B78">Lasky-Su et al., 2008</xref>). SLC9A9 is a gene of interest and has also been found to be implicated in other ADHD studies (<xref ref-type="bibr" rid="B125">Zhang-James et al., 2011</xref>; <xref ref-type="bibr" rid="B126">Zhang-James et al., 2012</xref>). The outcome of such studies underscores a significant genetic impact on the development of ADHD. In essence, the observed heightened risk in siblings of individuals with ADHD highlights the considerable influence of genetic factors in the onset of this neurodevelopmental disorder. This insight enhances our understanding of the complex interplay between genetics and environmental factors in the susceptibility to ADHD.</p>
<p>Genome-wide association studies have been instrumental in identifying specific genetic markers associated with ADHD (<xref ref-type="bibr" rid="B56">Franke et al., 2009</xref>). These markers are linked to the disorder and offer insights into related traits and comorbidities (<xref ref-type="bibr" rid="B83">Mehta et al., 2020</xref>). The intricate genetic landscape of ADHD involves a complex interplay of risk and protective factors, environmental influences, and gene-environment interactions (<xref ref-type="bibr" rid="B70">Kim et al., 2020</xref>). Moreover, epigenetic mechanisms contribute to the dynamic nature of ADHD genetics (<xref ref-type="bibr" rid="B85">Mill and Petronis, 2008</xref>). Environmental factors, such as prenatal exposure to certain substances or stressors, can modify gene expression, potentially influencing ADHD susceptibility (<xref ref-type="bibr" rid="B85">Mill and Petronis, 2008</xref>). Understanding these epigenetic processes is crucial for a more nuanced comprehension of the disorder&#x2019;s etiology (<xref ref-type="bibr" rid="B89">Nigg, 2018</xref>).</p>
<p>In a genome-wide association (GWA) research meta-analysis of ADHD, <xref ref-type="bibr" rid="B44">Demontis et al. (2023)</xref> included 186,843 controls and 38,691 ADHD sufferers. About 27 genome-wide important loci were found, and 76 possible risk genes that are enriched in genes expressed specifically in the early stages of brain development were highlighted. In general, several brain-specific neuronal subtypes and midbrain dopaminergic neurons were linked to the hereditary risk of ADHD (<xref ref-type="bibr" rid="B44">Demontis et al., 2023</xref>). GWAS have led to the conclusion that there is an overlap in the genetics of ADHD and Bipolar disorder. For instance, DAT1, recently renamed as SLCA3 (<xref ref-type="bibr" rid="B115">Villani et al., 2018</xref>), is hypothesized to be associated with ADHD and has been confirmed to be linked to bipolar disorder. Interestingly, in psychiatry, genetic markers at the DAT1 locus appear to be able to predict clinical heterogeneity since the non-conduct disordered subtype of ADHD is associated with DAT1. In contrast, other subgroups do not appear to be connected. It is becoming increasingly apparent that the candidate genes for bipolar mania and candidate genes for an ADHD subtype are related (<xref ref-type="bibr" rid="B94">Polanczyk et al., 2014</xref>). In a study conducted in Oman, researchers investigated the frequency of VNTR alleles in DAT1 and their correlation with ADHD. They genotyped 92 Omani children with ADHD and 110 healthy controls, identifying two common alleles (DAT19 and DAT110). The DAT1&#x2a;10 allele showed similar distribution between ADHD (64.6%) and control groups (60.9%), but was more prevalent in ADHD males (69.4%) compared to females (55%), a distinction absent in controls (<xref ref-type="bibr" rid="B104">Simsek et al., 2005</xref>). Given the high rate of consanguineous marriages in the GCC region, further twin studies and broader research are warranted to explore the genetic foundations of disorders like ADHD in the Arab world. The discovery of novel genetic variants associated with ADHD will foster the early detection of the disease.</p>
<p>Furthermore, epigenetic processes, which regulate gene expression, are proposed as a significant biological marker and potentially a molecular mediator of genetic and environmental influences on ADHD. A high level of DNA methylation has been associated with repression of gene expression, but recent data have shown that this association can vary depending on factors including the location of the methylation in the gene sequence. Several studies have concluded that investigating epigenetic effects on human behavior is challenging because epigenetic changes vary widely from one tissue to another. In the brain alone, DNA methylation can vary considerably from one region to another or from one system to another. However, there are also cross-tissue correlation patterns of individual-specific epigenetic marks, suggesting that DNA methylation studies of peripheral tissue DNA in psychiatry are generally considered informative (<xref ref-type="bibr" rid="B121">Wilmot et al., 2016</xref>; <xref ref-type="bibr" rid="B86">Mirkovic et al., 2020</xref>).</p>
<p>Vasoactive intestinal peptide receptor 2&#x2033;encoded by VIPR2&#x2033; is present throughout the central nervous system and peripheral tissues. In a methylome-wide exploration of DNA methylation in peripheral tissue <xref ref-type="bibr" rid="B121">Wilmot et al. (2016)</xref> examined salivary DNA from children with ADHD compared to non-ADHD controls (<xref ref-type="bibr" rid="B121">Wilmot et al., 2016</xref>). They have found that probes in VIPR2 showed decreased CpG methylation in the saliva of children with ADHD. CpG methylation, which is essential for regulating gene expression, impacts a wide range of biological processes, from development to aging and inflammation. CpG islands, located in DNA methylation regions within promoters, are known to control gene expression by silencing transcription, playing a vital role in gene expression and tissue-specific functions (<xref ref-type="bibr" rid="B121">Wilmot et al., 2016</xref>).</p>
<p>Mutations in the ST3GAL3 gene, which encodes the Golgi enzyme &#x3b2;-galactoside-&#x3b1;2,3-sialyltransferase-III, are believed to play a role in the development of advanced cognitive abilities. This enzyme is crucial for the addition of sialic acid to glycoproteins and glycolipids, a process essential for proper brain function. Disruptions in this enzyme&#x2019;s activity due to mutations in ST3GAL3 could potentially affect neural connectivity and signaling, thereby influencing higher-order cognitive functions such as learning, memory, and problem-solving. Research into these mutations helps to understand how specific genetic factors contribute to the complexities of cognitive development (<xref ref-type="bibr" rid="B84">Mijailovic et al., 2022</xref>). A genome-wide methylome analysis uncovered that ST3GAL3 undergoes differential methylation throughout the progression of ADHD. This suggests that gene-environment interactions might influence the expression of ST3GAL3, affecting the epigenetic regulation of brain development and maturation (<xref ref-type="bibr" rid="B117">Walton et al., 2017</xref>). <xref ref-type="bibr" rid="B97">Rivero et al. (2021)</xref> has established when investigating on mice models, that male St3gal3 heterozygous mice exhibit cognitive deficits, while female heterozygous mice show increased activity and improved cognitive control compared to the wildtype mice (<xref ref-type="bibr" rid="B97">Rivero et al., 2021</xref>). The research also identified subtle, sex-specific, and region-specific changes in the expression of various markers associated with oligodendrogenesis, myelin formation, protein sialylation, and cell adhesion/synaptic target glycoproteins of ST3GAL3. These findings suggest that ST3GAL3 haploinsufficiency leads to sex-dependent alterations in cognition, behavior, and brain plasticity markers. Additionally, St3gal3-deficient mice displayed behavioral changes similar to those observed in ADHD, such as differences in locomotor activity and cognitive performance, with male heterozygous mice specifically showing memory impairments in place learning tasks, a common issue in ADHD (<xref ref-type="bibr" rid="B97">Rivero et al., 2021</xref>).</p>
<p>Despite significant strides, challenges persist in unraveling the complete genetic architecture of ADHD. Heterogeneity within the disorder (<xref ref-type="bibr" rid="B50">Faraone, 2000</xref>), the influence of non-genetic factors (<xref ref-type="bibr" rid="B85">Mill and Petronis, 2008</xref>), and the intricate nature of gene interactions (<xref ref-type="bibr" rid="B2">Acosta et al., 2011</xref>) pose ongoing research challenges. In the realm of personalized medicine, genetic insights into ADHD hold promise for tailoring interventions (<xref ref-type="bibr" rid="B28">Buitelaar et al., 2022</xref>). Identifying genetic markers may pave the way for targeted therapies, allowing for more precise and effective treatment approaches (<xref ref-type="bibr" rid="B83">Mehta et al., 2020</xref>).</p>
<p>In the context of GWAS, there are only a few studies that directly identified variants with ADHD. The absence of positive findings suggests that the influence of individual common ADHD risk variants is likely to be minor, given the disorder&#x2019;s high heritability. Alternatively, this prompts consideration that other types of variants, such as rare ones, might play a more significant role in contributing to the heritability of ADHD. These findings suggest that more GWAS should be performed from countries like Saudi Arabia with high consanguinity rates to aid researchers in identifying rare variants that are associated with ADHD.</p>
<p>Differences in linkage disequilibrium (LD) patterns among populations play a pivotal role in influencing the transferability of GWA findings. A variant strongly associated with a trait in one population may not exhibit a detectable association in another population due to differences in LD with the unknown causal variant. Given the pronounced disparities in LD observed among European, East Asian, and Arab populations, it becomes essential to account for these population-specific LD variations when evaluating the transferability of GWA-identified associations.</p>
<p>Research on ADHD in the Arab world, especially in the GCC region, has primarily concentrated on behavioral and epidemiological studies, with limited attention to the genetic and epigenetic factors underlying the disorder. The Arab population, characterized by large family sizes, high rates of consanguinity, and frequent first-cousin marriages, presents a unique genetic landscape that leads to increased homozygosity for both monogenic and polygenic diseases, and the accumulation of deleterious recessive alleles. This distinctive genetic profile makes the Arab population particularly valuable for genetic and epigenetic research, including twin and extended family studies, which could offer profound insights into the complex interplay between genetics and health. Despite these opportunities, the representation of the Arab population in global GWAS is inadequate, and the applicability of GWA findings to this group remains underexplored. Expanding genetic and epigenetic research on ADHD in the GCC is crucial to ensure that findings from global studies are relevant and beneficial to the Arab population, and to enhance our understanding of the disorder&#x2019;s biological foundations in this unique context.</p>
</sec>
<sec id="s5">
<title>5 Epidemiology and prevalence of ADHD</title>
<p>Although prevalence rates and reported changes in the prevalence of ADHD vary greatly depending on country and region, technique, and sample, it appears to be a global phenomenon (<xref ref-type="bibr" rid="B93">Polanczyk et al., 2015</xref>). In 2014, Polanczyk et al. conducted a meta-analysis study that revealed a 5.8% global prevalence rate for children and adolescents (<xref ref-type="bibr" rid="B94">Polanczyk et al., 2014</xref>). Different criteria for identifying ADHD are causing slightly higher (e.g., 7.2%) prevalence percentages reported by other meta-analyses conducted by <xref ref-type="bibr" rid="B110">Thomas et al. (2015)</xref>. Peak prevalence may be significantly greater in some age groups, such as 13% in 9-year-old boys although prevalence statistics in children and adolescents represent average values across the entire age range (<xref ref-type="bibr" rid="B19">Bachmann et al., 2017</xref>). The estimated prevalence of ADHD in adults worldwide is 2.8% with greater rates observed in high-income nations (3.6%) compared to low-income ones (1.4%) (<xref ref-type="bibr" rid="B19">Bachmann et al., 2017</xref>).</p>
<sec id="s5-1">
<title>5.1 Current status of ADHD in Arabian Gulf Nations</title>
<p>The six Arab Gulf states that make up the Gulf Cooperation Council (GCC) consist of Bahrain, Kuwait, Oman, Qatar, the United Arab Emirates, and Saudi Arabia, which is the largest country, and are all disproportionately affected by the &#x201c;youth bulge&#x201d; with a combined population of approximately 54 million (<xref ref-type="bibr" rid="B112">Thygesen et al., 2021</xref>). However, the GCC is classified as in the &#x201c;second phase of demography in transition&#x201d; (<xref ref-type="bibr" rid="B91">Omran, 2005</xref>). As a result, this stage is frequently distinguished by high rates of conception and births and the prevalence of a population structure resembling a pyramid-like population structure. Systematic clinical data in this regard point to a significant number of children with disabilities in the GCC (<xref ref-type="bibr" rid="B34">Chan et al., 2021</xref>). This might be caused by the high rates of polygamous marriages and consanguinity among married couples, especially among older males, as well as high fertility and frequent childbirth. Moreover, the majority of GCC nations have not yet created policies to assist young people with special needs (<xref ref-type="bibr" rid="B95">Qoronfleh et al., 2019</xref>). Although it is still in its early stages, research on the prevalence of ADHD diseases in the GCC has emerged (<xref ref-type="bibr" rid="B49">Farah et al., 2009</xref>). To fill this gap in the literature, this study aimed to critically review the literature on the prevalence rates of ADHD disorders in the GCC (<xref ref-type="table" rid="T3">Table 3</xref>). A glimpse into the literature shows that ADHD disorder has received some attention in this region. In a research of PubMed, a total of 33 studies from the six countries were found (<xref ref-type="bibr" rid="B34">Chan et al., 2021</xref>). Focusing on the genetics of ADHD, only eight studies were found in the KSA, one in UAE, Kuwait, Qatar, and Oman.</p>
<table-wrap id="T3" position="float">
<label>TABLE 3</label>
<caption>
<p>Present studies conducted in the Gulf Cooperation Council (GCC) region. ADHD, attention-deficit hyperactivity disorder.</p>
</caption>
<table>
<thead valign="top">
<tr>
<th align="center">No.</th>
<th align="center">Country</th>
<th align="center">Study setting</th>
<th align="center">Sample size</th>
<th align="center">Age range (Years)</th>
<th align="center">Screening tool</th>
<th align="center">Disorder screened</th>
<th align="center">Positive cases (%)</th>
<th align="center">Author (Year)<break/>References</th>
</tr>
</thead>
<tbody valign="top">
<tr>
<td align="left">1</td>
<td rowspan="7" align="left">Saudi Arabia</td>
<td align="left">Hospital</td>
<td align="left">n &#x3d; 416</td>
<td align="left">0&#x2013;18</td>
<td align="left">DSM III-R/DSM IV</td>
<td align="left">ADHD</td>
<td align="left">ADHD &#x3d; 106 (25.5%)</td>
<td align="left">
<xref ref-type="bibr" rid="B5">Al-Haidar (2003)</xref>
</td>
</tr>
<tr>
<td align="left">2</td>
<td rowspan="6" align="left">School</td>
<td align="left">n &#x3d; 1,287</td>
<td align="left">6&#x2013;13</td>
<td align="left">ADDES</td>
<td align="left">ADHD</td>
<td align="left">ADHD &#x3d; 572 (45.11%)</td>
<td align="left">
<xref ref-type="bibr" rid="B6">Al Hamed et al. (2008)</xref>
</td>
</tr>
<tr>
<td align="left">3</td>
<td align="left">n &#x3d; 642</td>
<td align="left">7&#x2013;9</td>
<td align="left">DSM-IV-TR</td>
<td align="left">ADHD</td>
<td align="left">ADHD &#x3d; 33 (5.0%) [DSM-IV-TR]</td>
<td align="left">
<xref ref-type="bibr" rid="B8">Alqahtani (2010)</xref>
</td>
</tr>
<tr>
<td align="left">4</td>
<td align="left">n &#x3d; 708</td>
<td align="left">7&#x2013;9</td>
<td align="left">VADHDDRS</td>
<td align="left">ADHD</td>
<td align="left">ADHD &#x3d; 29 (4.1%)</td>
<td align="left">
<xref ref-type="bibr" rid="B66">Jenahi et al. (2012)</xref>
</td>
</tr>
<tr>
<td align="left">5</td>
<td align="left">n &#x3d; 1,009</td>
<td align="left">6&#x2013;15</td>
<td align="left">ADDES</td>
<td align="left">ADHD</td>
<td align="left">ADHD &#x3d; 107 (11.3%)</td>
<td align="left">
<xref ref-type="bibr" rid="B66">Jenahi et al. (2012)</xref>
</td>
</tr>
<tr>
<td align="left">6</td>
<td align="left">n &#x3d; 929</td>
<td align="left">6&#x2013;12</td>
<td align="left">VADHDDRS</td>
<td align="left">ADHD</td>
<td align="left">ADHD &#x3d; 46 (11.6%)</td>
<td align="left">
<xref ref-type="bibr" rid="B10">AlZaben et al. (2018)</xref>
</td>
</tr>
<tr>
<td align="left">7</td>
<td align="left">n &#x3d; 2,770</td>
<td align="left">6&#x2013;12</td>
<td align="left">ADHDS</td>
<td align="left">ADHD</td>
<td align="left">ADHD &#x3d; 321 (11.6%)</td>
<td align="left">
<xref ref-type="bibr" rid="B52">Fatima and Ahmad (2018)</xref>
</td>
</tr>
<tr>
<td align="left">8</td>
<td align="left">United Arab Emirates</td>
<td align="left">School</td>
<td align="left">n &#x3d; 200</td>
<td align="left">11&#x2013;14</td>
<td align="left">DSM-IV</td>
<td align="left">ADHD</td>
<td align="left">ADHD &#x3d; 25 (12.5%)</td>
<td align="left">
<xref ref-type="bibr" rid="B39">Cook et al. (1995)</xref>
</td>
</tr>
<tr>
<td align="left">9</td>
<td align="left">Kuwait</td>
<td align="left">Hospital</td>
<td align="left">n &#x3d; 135</td>
<td align="left">6&#x2013;15</td>
<td align="left">VADHDDRS-PRS (Arabic)/SSPI/WIS/MINI-KID</td>
<td align="left">ADHD</td>
<td align="left">ADHD &#x3d; 70 (51.9%)</td>
<td align="left">
<xref ref-type="bibr" rid="B89">Nigg (2018)</xref>
</td>
</tr>
<tr>
<td align="left">10</td>
<td align="left">Qatar</td>
<td align="left">School</td>
<td align="left">n &#x3d; 4,489</td>
<td align="left">6&#x2013;19</td>
<td align="left">SNAP-IV RS</td>
<td align="left">ADHD</td>
<td align="left">ADHD &#x3d; 373 (8.3%)</td>
<td align="left">
<xref ref-type="bibr" rid="B27">Bradshaw and Kamal (2017)</xref>
</td>
</tr>
<tr>
<td align="left">11</td>
<td align="left">Oman</td>
<td align="left">School</td>
<td align="left">n &#x3d; 328</td>
<td align="left">9&#x2013;10</td>
<td align="left">VADHDDRS-TAS</td>
<td align="left">ADHD</td>
<td align="left">ADHD &#x3d; 28 (8.8%)</td>
<td align="left">
<xref ref-type="bibr" rid="B4">Al-Ghannami et al. (2018)</xref>
</td>
</tr>
</tbody>
</table>
</table-wrap>
<p>Research specifically focused on the genetics of ADHD within GCC populations is very limited. Most of the genetic studies on ADHD have been conducted in Western populations (<xref ref-type="bibr" rid="B77">Larsson et al., 2006</xref>; <xref ref-type="bibr" rid="B110">Thomas et al., 2015</xref>). However, genetic factors contributing to ADHD are expected to be similar across different populations due to the high heritability of the disorder (<xref ref-type="bibr" rid="B51">Faraone and Larsson, 2019</xref>). Generally, the GCC appears to be among the growing economies where the environmental aspect plays an important role in population health. In addition to genetic factors, cultural, social, and environmental factors in the GCC can influence the prevalence and presentation of ADHD (<xref ref-type="bibr" rid="B127">Zheng et al., 2020</xref>). For example, in 2022, a study by Setyanisa et al. presented those differences in educational systems, parenting styles, and societal attitudes toward mental health can impact the diagnosis and management of ADHD (<xref ref-type="bibr" rid="B103">Setyanisa et al., 2022</xref>). While the core genetic risk factors for ADHD are likely to be similar globally, there may be population-specific genetic variants in the GCC countries due to genetic drift, founder effects, and consanguinity, which is more common in the GCC than in many other regions specifically in Saudi Arabia (<xref ref-type="bibr" rid="B20">Bakry et al., 2023</xref>).</p>
</sec>
<sec id="s5-2">
<title>5.2 Consanguinity in Saudi Arabia</title>
<p>The Arabian Peninsula is known for its high rate of consanguinity. In Saudi Arabia, consanguineous marriage accounted for 52.0% of marriages, with an average inbreeding value of 0.0312 (<xref ref-type="bibr" rid="B3">Al-Abdulkareem and Ballal, 1998</xref>). Consanguineous marriage is one of the main risk factors that contribute to the spread of genetic syndrome. Therefore, there is a significant prevalence of genetic abnormalities in Saudi Arabia (<xref ref-type="bibr" rid="B20">Bakry et al., 2023</xref>). Several neurodevelopmental disorders were studied genetically and several variants were reported globally. However, Arab countries specifically Saudi Arabia need more attention to discover the genetic route of ADHD. In this land of the world, the genetic cause of ADHD is still a mystery due to the high rate of consanguinity.</p>
<p>In consanguineous populations such as Saudi Arabia, the probability of both parents carrying the same recessive gene mutation is significantly higher compared to low rates of consanguinity populations (<xref ref-type="bibr" rid="B61">Hamamy, 2012</xref>). Accordingly, the incidence of autosomal recessive disorders is more frequent in populations with a high rate of consanguinity (<xref ref-type="bibr" rid="B68">Khayat et al., 2024</xref>). High rates of consanguinity can increase the prevalence of certain genetic disorders, including those with complex inheritance patterns (<xref ref-type="bibr" rid="B82">Mahrous et al., 2023</xref>; <xref ref-type="bibr" rid="B102">Semlali et al., 2018a</xref>; <xref ref-type="bibr" rid="B101">Semlali et al., 2018b</xref>; <xref ref-type="bibr" rid="B63">Hawsawi et al., 2019</xref>), and ADHD. ADHD is a multifactorial disorder, meaning multiple genes and environmental factors influence it (<xref ref-type="bibr" rid="B124">Zayats and Neale, 2019</xref>). Certain genetic variants have been associated with an increased risk of ADHD, affecting neurotransmitter systems such as dopamine and serotonin (<xref ref-type="bibr" rid="B123">Yadav et al., 2021</xref>). Consanguineous marriages increase the probability of inheriting identical genetic variants from both parents. This can increase the risk of recessive genetic disorders and also contribute to the expression of complex genetic traits, including ADHD (<xref ref-type="bibr" rid="B65">Jackson et al., 2018</xref>). The increased genetic homogeneity in consanguineous populations can lead to a higher prevalence of certain alleles that may contribute to ADHD.</p>
<p>Studies in Saudi Arabia have identified a higher prevalence of certain genetic disorders due to high rates of consanguinity. Unfortunately, research specific to ADHD in consanguineous populations is limited but suggests a potential link between consanguinity and the genetic factors contributing to ADHD (<xref ref-type="bibr" rid="B68">Khayat et al., 2024</xref>). Therefore, the higher rates of ADHD in consanguineous populations could necessitate tailored public health strategies, including genetic counseling and targeted interventions. Understanding the genetic link can help in developing specific diagnostic tools and treatments for ADHD in populations with high consanguinity rates.</p>
<p>While the direct link between consanguinity and ADHD genetics in Saudi Arabia requires more research, the increased prevalence of genetic variants in consanguineous populations can contribute to a higher incidence of ADHD. This underscores the importance of genetic studies and targeted healthcare strategies in these populations (<xref ref-type="bibr" rid="B9">Alrefaei et al., 2022</xref>).</p>
</sec>
</sec>
<sec id="s6">
<title>6 Current treatment and management of ADHD</title>
<p>Living with ADHD presents a unique set of challenges and opportunities. While the journey may be marked by moments of distraction and impulsivity (<xref ref-type="bibr" rid="B120">Wiklund et al., 2017</xref>), individuals with ADHD often possess remarkable creativity and an ability to think outside the box (<xref ref-type="bibr" rid="B119">White and Shah, 2011</xref>) (<xref ref-type="fig" rid="F1">Figure 1</xref>). Attention deficit hyperactivity disorder is not a one-size-fits-all condition; it manifests differently in each person. Some may struggle with maintaining focus (<xref ref-type="bibr" rid="B7">Aliabadi et al., 2016</xref>), while others may grapple with impulsive decision-making (<xref ref-type="bibr" rid="B64">Hayashibara et al., 2023</xref>). However, it is crucial to recognize that ADHD is not a deficit of attention but a difference in attention (<xref ref-type="bibr" rid="B17">Baas et al., 2008</xref>). Embracing this perspective allows individuals to tap into their strengths and cultivate coping mechanisms (<xref ref-type="bibr" rid="B57">Fredrickson, 2000</xref>). One of the keys to navigating life with ADHD is developing personalized strategies (<xref ref-type="bibr" rid="B79">Lazar and Stein, 2017</xref>) (<xref ref-type="fig" rid="F5">Figure 5</xref>). From utilizing visual aids and setting clear routines to breaking tasks into manageable chunks, individuals with ADHD can enhance their productivity and overall wellbeing (<xref ref-type="bibr" rid="B21">Bawden and Robinson, 2009</xref>; <xref ref-type="bibr" rid="B107">Spiel et al., 2022</xref>). By adopting a proactive mentality, people can transform possible obstacles into chances for development (<xref ref-type="bibr" rid="B30">Cani&#xeb;ls et al., 2018</xref>).</p>
<fig id="F5" position="float">
<label>FIGURE 5</label>
<caption>
<p>Schematic representation of approaches to treat and manage symptoms and promote positive behavior for individuals with ADHD.</p>
</caption>
<graphic xlink:href="fgene-15-1405453-g005.tif"/>
</fig>
<p>Support from friends, family, and the community plays a pivotal role in empowering individuals with ADHD (<xref ref-type="bibr" rid="B40">Craig et al., 2020</xref>; <xref ref-type="bibr" rid="B36">Claussen et al., 2022</xref>). Educating those around us about the nuances of ADHD fosters understanding (<xref ref-type="bibr" rid="B36">Claussen et al., 2022</xref>). Creating an environment that embraces neurodiversity not only reduces stigma but also encourages the celebration of unique perspectives and talents (<xref ref-type="bibr" rid="B14">Armstrong, 2012</xref>). In the workplace, accommodations that cater to the specific needs of individuals with ADHD can significantly enhance their performance (<xref ref-type="bibr" rid="B100">Sarkis, 2014</xref>). Flexible work arrangements, clear communication channels, and recognition of accomplishments contribute to a positive and inclusive professional environment (<xref ref-type="bibr" rid="B71">Kirby and Smith, 2021</xref>). While medication may be a part of the treatment plan for some (<xref ref-type="bibr" rid="B42">Dalton, 2013</xref>), it is important to emphasize that there&#x2019;s no one-size-fits-all solution for managing ADHD (<xref ref-type="bibr" rid="B37">Coghill, 2017</xref>). Standard treatment and management for ADHD involve medication, behavioral intervention, nutrition, and supplements is presented in <xref ref-type="table" rid="T4">Table 4</xref>. Holistic approaches, including mindfulness, exercise, and proper nutrition, can complement traditional treatments and contribute to overall wellbeing (<xref ref-type="bibr" rid="B73">Kobe, 2023</xref>). In conclusion, living with ADHD is a journey filled with both challenges and opportunities. By fostering understanding, embracing uniqueness, and developing personalized strategies, individuals with ADHD can navigate life successfully while contributing their distinct talents to the world.</p>
<table-wrap id="T4" position="float">
<label>TABLE 4</label>
<caption>
<p>Current attention-deficit hyperactivity disorder (ADHD) treatment plan.</p>
</caption>
<table>
<thead valign="top">
<tr>
<th align="center">Current treatments</th>
<th align="center">Subgroup</th>
<th align="center">Effects</th>
</tr>
</thead>
<tbody valign="top">
<tr>
<td align="left">Medications (<xref ref-type="bibr" rid="B53">FDA, 2023</xref>)</td>
<td align="left">- Stimulants, which contains methylphenidate and amphetamine. For example, Intuniv (guanfacine), Strattera (atomoxetine), Kapvay (clonidine) and Qelbree (viloxazine) (<xref ref-type="bibr" rid="B53">FDA, 2023</xref>)<break/>- Non-stimulants (<xref ref-type="bibr" rid="B53">FDA, 2023</xref>)</td>
<td align="left">- Stimulants increases brain levels of dopamine, a neurotransmitter associated with motivation, attention and movement. Increase brain levels of dopamine, a neurotransmitter associated with motivation, attention and movement (<xref ref-type="bibr" rid="B53">FDA, 2023</xref>)<break/>- Non stimulants medications treat the ADHD symptoms (<xref ref-type="bibr" rid="B53">FDA, 2023</xref>)</td>
</tr>
<tr>
<td align="left">Cognitive behavioral therapy for affected children (<xref ref-type="bibr" rid="B27">Bradshaw and Kamal, 2017</xref>)</td>
<td align="left">Parents and school are provided with behavior-management training programs as well (<xref ref-type="bibr" rid="B4">Al-Ghannami et al., 2018</xref>)</td>
<td align="left">Help in managing the symptoms (<xref ref-type="bibr" rid="B27">Bradshaw and Kamal, 2017</xref>)</td>
</tr>
<tr>
<td align="left">Balanced diet and proper nutrition (<xref ref-type="bibr" rid="B122">Wolraich et al., 2019</xref>)</td>
<td align="left">- Specific dietary elimination is advisable if there is a clear link with ADHD behavior (<xref ref-type="bibr" rid="B54">Ferguson, 2000</xref>)<break/>- Some studies suggested using Omega-3 and Omega-6 fatty acid supplements (<xref ref-type="bibr" rid="B67">Kemper et al., 2018</xref>)</td>
<td align="left">There is insufficient evidence on the benefits of using Omega3/6 fatty acid supplements (<xref ref-type="bibr" rid="B67">Kemper et al., 2018</xref>)</td>
</tr>
</tbody>
</table>
</table-wrap>
</sec>
<sec sec-type="conclusion" id="s7">
<title>7 Conclusion</title>
<p>The characteristic features of individuals with ADHD include hyperactivity, inattentiveness, and impulsiveness, which lead to impairments in daily living. Research recognized that ADHD was not just a childhood disorder, that disappeared with age as was previously thought. Scientists have been trying to identify the causes of ADHD. It is a clinically and genetically heterogeneous syndrome that is comorbid with childhood conduct disorder, alcoholism, substance abuse, antisocial personality disorder, and affective disorders. The ADHD consistent overlap with autistic symptoms has also been established. Research points to a strong genetic link, yet it is not clear what role environmental factors play in determining who develops ADHD. Psychoeducation, counseling, supportive problem-directed therapy, behavioral intervention, coaching, cognitive remediation, and couples and family therapy are useful adjuncts to medication management.</p>
<p>In conclusion, this comprehensive review underscores the intricate genetic landscape of ADHD. While considerable progress has been made in identifying genetic markers and understanding heritability, continued research efforts are needed to unravel the full complexity of ADHD genetics in different populations, offering hope for more individualized and effective interventions in the future.</p>
</sec>
<sec id="s8">
<title>8 Future perspectives</title>
<p>In the realm of ADHD research in the Arab World, it is imperative to focus on several key aspects for future advancements. First and foremost, there is a critical need to enhance cultural awareness and education surrounding ADHD, dispelling misconceptions, and promoting understanding within the Arab community. Additionally, research efforts should span different demographic levels, exploring variations in ADHD prevalence across urban and rural settings, socioeconomic factors, and access to healthcare resources. Early intervention programs tailored to the unique needs of the Arab population should be established, with training initiatives for educators, parents, and healthcare professionals. Given the cultural landscape, investigating the correlation between consanguinity and ADHD prevalence is crucial, necessitating genetic research to identify specific risk factors. Moreover, GWA and genetic mapping studies should be actively pursued in the Arab World to provide a more holistic insight into the genetic underpinnings of ADHD. Furthermore, community engagement initiatives and support networks can contribute to a more inclusive and understanding environment for individuals affected by ADHD. Finally, improvements in healthcare infrastructure are essential to ensure widespread access to accurate diagnosis and effective treatment, addressing disparities and making ADHD interventions more accessible throughout the Arab World.</p>
</sec>
</body>
<back>
<sec id="s9">
<title>Author contributions</title>
<p>NM: Data curation, Validation, Visualization, Writing&#x2013;original draft, Writing&#x2013;review and editing, Formal Analysis, Software. AA: Formal Analysis, Visualization, Writing&#x2013;original draft, Writing&#x2013;review and editing, Investigation. RS: Investigation, Visualization, Writing&#x2013;original draft, Writing&#x2013;review and editing, Conceptualization, Project administration, Supervision, Validation. BK: Investigation, Visualization, Writing&#x2013;original draft, Writing&#x2013;review and editing, Data curation. MK: Data curation, Investigation, Visualization, Writing&#x2013;original draft, Writing&#x2013;review and editing, Formal Analysis, Funding acquisition, Project administration, Validation. YH: Data curation, Project administration, Validation, Visualization, Writing&#x2013;original draft, Writing&#x2013;review and editing.</p>
</sec>
<sec sec-type="funding-information" id="s10">
<title>Funding</title>
<p>The author(s) declare that financial support was received for the research, authorship, and/or publication of this article. This work has been funded by the King Salman Center for Disability Research for their financial support under grant no: KSRG-2023-145.</p>
</sec>
<ack>
<p>NNM would like to thank the University of Hafr Al-Batin and YH would like to thank King Faisal Specialist Hospital &#x26; Research Centre (Gen. Org) (KFSH and RC-Jed) for their support and approval (IRB approval &#x23; 2024-19).</p>
</ack>
<sec sec-type="COI-statement" id="s11">
<title>Conflict of interest</title>
<p>The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.</p>
</sec>
<sec sec-type="disclaimer" id="s12">
<title>Publisher&#x2019;s note</title>
<p>All claims expressed in this article are solely those of the authors and do not necessarily represent those of their affiliated organizations, or those of the publisher, the editors and the reviewers. Any product that may be evaluated in this article, or claim that may be made by its manufacturer, is not guaranteed or endorsed by the publisher.</p>
</sec>
<ref-list>
<title>References</title>
<ref id="B1">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Abdelnour</surname>
<given-names>E.</given-names>
</name>
<name>
<surname>Jansen</surname>
<given-names>M. O.</given-names>
</name>
<name>
<surname>Gold</surname>
<given-names>J. A.</given-names>
</name>
</person-group> (<year>2022</year>). <article-title>ADHD diagnostic trends: increased recognition or overdiagnosis?</article-title> <source>Mo Med.</source> <volume>119</volume> (<issue>5</issue>), <fpage>467</fpage>&#x2013;<lpage>473</lpage>.</citation>
</ref>
<ref id="B2">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Acosta</surname>
<given-names>M.</given-names>
</name>
<name>
<surname>Velez</surname>
<given-names>J.</given-names>
</name>
<name>
<surname>Bustamante</surname>
<given-names>M.</given-names>
</name>
<name>
<surname>Balog</surname>
<given-names>J.</given-names>
</name>
<name>
<surname>Arcos-Burgos</surname>
<given-names>M.</given-names>
</name>
<name>
<surname>Muenke</surname>
<given-names>M.</given-names>
</name>
</person-group> (<year>2011</year>). <article-title>A two-locus genetic interaction between LPHN3 and 11q predicts ADHD severity and long-term outcome</article-title>. <source>Transl. Psychiatry</source> <volume>1</volume> (<issue>7</issue>), <fpage>e17</fpage>. <pub-id pub-id-type="doi">10.1038/tp.2011.14</pub-id>
</citation>
</ref>
<ref id="B3">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Al-Abdulkareem</surname>
<given-names>A. A.</given-names>
</name>
<name>
<surname>Ballal</surname>
<given-names>S. G.</given-names>
</name>
</person-group> (<year>1998</year>). <article-title>Consanguineous marriage in an urban area of Saudi Arabia: rates and adverse health effects on the offspring</article-title>. <source>J. Community Health</source> <volume>23</volume> (<issue>1</issue>), <fpage>75</fpage>&#x2013;<lpage>83</lpage>. <pub-id pub-id-type="doi">10.1023/a:1018727005707</pub-id>
</citation>
</ref>
<ref id="B4">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Al-Ghannami</surname>
<given-names>S. S.</given-names>
</name>
<name>
<surname>Al-Adawi</surname>
<given-names>S.</given-names>
</name>
<name>
<surname>Ghebremeskel</surname>
<given-names>K.</given-names>
</name>
<name>
<surname>Cramer</surname>
<given-names>M. T.</given-names>
</name>
<name>
<surname>Hussein</surname>
<given-names>I. S.</given-names>
</name>
<name>
<surname>Min</surname>
<given-names>Y.</given-names>
</name>
<etal/>
</person-group> (<year>2018</year>). <article-title>Attention deficit hyperactivity disorder and parental factors in school children aged nine to ten years in muscat, Oman</article-title>. <source>Oman Med. J.</source> <volume>33</volume> (<issue>3</issue>), <fpage>193</fpage>&#x2013;<lpage>199</lpage>. <pub-id pub-id-type="doi">10.5001/omj.2018.37</pub-id>
</citation>
</ref>
<ref id="B5">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Al-Haidar</surname>
<given-names>F. A.</given-names>
</name>
</person-group> (<year>2003</year>). <article-title>Co-morbidity and treatment of attention deficit hyperactivity disorder in Saudi Arabia</article-title>. <source>East Mediterr. Health J.</source> <volume>9</volume> (<issue>5-6</issue>), <fpage>988</fpage>&#x2013;<lpage>995</lpage>. <pub-id pub-id-type="doi">10.26719/2003.9.5-6.988</pub-id>
</citation>
</ref>
<ref id="B6">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Al Hamed</surname>
<given-names>J. H.</given-names>
</name>
<name>
<surname>Taha</surname>
<given-names>A. Z.</given-names>
</name>
<name>
<surname>Sabra</surname>
<given-names>A. A.</given-names>
</name>
<name>
<surname>Bella</surname>
<given-names>H.</given-names>
</name>
</person-group> (<year>2008</year>). <article-title>Attention deficit hyperactivity disorder (ADHD) among male primary school children in Dammam, Saudi Arabia: prevalence and associated factors</article-title>. <source>J. Egypt Public Health Assoc.</source> <volume>83</volume> (<issue>3-4</issue>), <fpage>165</fpage>&#x2013;<lpage>182</lpage>.</citation>
</ref>
<ref id="B7">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Aliabadi</surname>
<given-names>B.</given-names>
</name>
<name>
<surname>Davari-Ashtiani</surname>
<given-names>R.</given-names>
</name>
<name>
<surname>Khademi</surname>
<given-names>M.</given-names>
</name>
<name>
<surname>Arabgol</surname>
<given-names>F.</given-names>
</name>
</person-group> (<year>2016</year>). <article-title>Comparison of creativity between children with and without attention deficit hyperactivity disorder: a case-control study</article-title>. <source>Iran. J. psychiatry</source> <volume>11</volume> (<issue>2</issue>), <fpage>99</fpage>&#x2013;<lpage>103</lpage>.</citation>
</ref>
<ref id="B8">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Alqahtani</surname>
<given-names>M. M.</given-names>
</name>
</person-group> (<year>2010</year>). <article-title>Attention-deficit hyperactive disorder in school-aged children in Saudi Arabia</article-title>. <source>Eur. J. Pediatr.</source> <volume>169</volume> (<issue>9</issue>), <fpage>1113</fpage>&#x2013;<lpage>1117</lpage>. <pub-id pub-id-type="doi">10.1007/s00431-010-1190-y</pub-id>
</citation>
</ref>
<ref id="B9">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Alrefaei</surname>
<given-names>A. F.</given-names>
</name>
<name>
<surname>Hawsawi</surname>
<given-names>Y. M.</given-names>
</name>
<name>
<surname>Almaleki</surname>
<given-names>D.</given-names>
</name>
<name>
<surname>Alafif</surname>
<given-names>T.</given-names>
</name>
<name>
<surname>Alzahrani</surname>
<given-names>F. A.</given-names>
</name>
<name>
<surname>Bakhrebah</surname>
<given-names>M. A.</given-names>
</name>
</person-group> (<year>2022</year>). <article-title>Genetic data sharing and artificial intelligence in the era of personalized medicine based on a cross-sectional analysis of the Saudi human genome program</article-title>. <source>Sci. Rep.</source> <volume>12</volume> (<issue>1</issue>), <fpage>1405</fpage>. <pub-id pub-id-type="doi">10.1038/s41598-022-05296-7</pub-id>
</citation>
</ref>
<ref id="B10">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>AlZaben</surname>
<given-names>F. N.</given-names>
</name>
<name>
<surname>Sehlo</surname>
<given-names>M. G.</given-names>
</name>
<name>
<surname>Alghamdi</surname>
<given-names>W. A.</given-names>
</name>
<name>
<surname>Tayeb</surname>
<given-names>H. O.</given-names>
</name>
<name>
<surname>Khalifa</surname>
<given-names>D. A.</given-names>
</name>
<name>
<surname>Mira</surname>
<given-names>A. T.</given-names>
</name>
<etal/>
</person-group> (<year>2018</year>). <article-title>Prevalence of attention deficit hyperactivity disorder and comorbid psychiatric and behavioral problems among primary school students in western Saudi Arabia</article-title>. <source>Saudi Med. J.</source> <volume>39</volume> (<issue>1</issue>), <fpage>52</fpage>&#x2013;<lpage>58</lpage>. <pub-id pub-id-type="doi">10.15537/smj.2018.1.21288</pub-id>
</citation>
</ref>
<ref id="B11">
<citation citation-type="journal">
<collab>American Academy of Pediatrics</collab>. (<year>2001</year>). <article-title>Clinical practice guideline: treatment of the school-aged child with attention-deficit/hyperactivity disorder</article-title>. <source>Pediatrics</source> <volume>108</volume> (<issue>4</issue>), <fpage>1033</fpage>&#x2013;<lpage>1044</lpage>. <pub-id pub-id-type="doi">10.1542/peds.108.4.1033</pub-id>
</citation>
</ref>
<ref id="B12">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Anokhin</surname>
<given-names>A. P.</given-names>
</name>
<name>
<surname>Golosheykin</surname>
<given-names>S.</given-names>
</name>
<name>
<surname>Grant</surname>
<given-names>J. D.</given-names>
</name>
<name>
<surname>Heath</surname>
<given-names>A. C.</given-names>
</name>
</person-group> (<year>2017</year>). <article-title>Heritability of brain activity related to response inhibition: a longitudinal genetic study in adolescent twins</article-title>. <source>Int. J. Psychophysiol.</source> <volume>115</volume>, <fpage>112</fpage>&#x2013;<lpage>124</lpage>. <pub-id pub-id-type="doi">10.1016/j.ijpsycho.2017.03.002</pub-id>
</citation>
</ref>
<ref id="B13">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Arcos-Burgos</surname>
<given-names>M.</given-names>
</name>
<name>
<surname>Castellanos</surname>
<given-names>F. X.</given-names>
</name>
<name>
<surname>Pineda</surname>
<given-names>D.</given-names>
</name>
<name>
<surname>Lopera</surname>
<given-names>F.</given-names>
</name>
<name>
<surname>Palacio</surname>
<given-names>J. D.</given-names>
</name>
<name>
<surname>Palacio</surname>
<given-names>L. G.</given-names>
</name>
<etal/>
</person-group> (<year>2004</year>). <article-title>Attention-deficit/hyperactivity disorder in a population isolate: linkage to loci at 4q13.2, 5q33.3, 11q22, and 17p11</article-title>. <source>Am. J. Hum. Genet.</source> <volume>75</volume> (<issue>6</issue>), <fpage>998</fpage>&#x2013;<lpage>1014</lpage>. <pub-id pub-id-type="doi">10.1086/426154</pub-id>
</citation>
</ref>
<ref id="B14">
<citation citation-type="book">
<person-group person-group-type="author">
<name>
<surname>Armstrong</surname>
<given-names>T.</given-names>
</name>
</person-group> (<year>2012</year>). <source>Neurodiversity in the classroom: strength-based strategies to help students with special needs succeed in school and life</source>. <publisher-loc>United States</publisher-loc>: <publisher-name>ASCD</publisher-name>.</citation>
</ref>
<ref id="B15">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Arnsten</surname>
<given-names>A. F.</given-names>
</name>
<name>
<surname>Pliszka</surname>
<given-names>S. R.</given-names>
</name>
</person-group> (<year>2011</year>). <article-title>Catecholamine influences on prefrontal cortical function: relevance to treatment of attention deficit/hyperactivity disorder and related disorders</article-title>. <source>Pharmacol. Biochem. Behav.</source> <volume>99</volume> (<issue>2</issue>), <fpage>211</fpage>&#x2013;<lpage>216</lpage>. <pub-id pub-id-type="doi">10.1016/j.pbb.2011.01.020</pub-id>
</citation>
</ref>
<ref id="B16">
<citation citation-type="book">
<collab>American Psychiatric Association</collab> (<year>1987</year>). <source>Diagnostic and statistical manual of mental health disorders (DSM-III-R)</source>. <publisher-name>American Psychiatric Association</publisher-name>.</citation>
</ref>
<ref id="B17">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Baas</surname>
<given-names>M.</given-names>
</name>
<name>
<surname>De Dreu</surname>
<given-names>C. K.</given-names>
</name>
<name>
<surname>Nijstad</surname>
<given-names>B. A.</given-names>
</name>
</person-group> (<year>2008</year>). <article-title>A meta-analysis of 25 years of mood-creativity research: hedonic tone, activation, or regulatory focus?</article-title> <source>Psychol. Bull.</source> <volume>134</volume> (<issue>6</issue>), <fpage>779</fpage>&#x2013;<lpage>806</lpage>. <pub-id pub-id-type="doi">10.1037/a0012815</pub-id>
</citation>
</ref>
<ref id="B18">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Baccarin</surname>
<given-names>M.</given-names>
</name>
<name>
<surname>Picinelli</surname>
<given-names>C.</given-names>
</name>
<name>
<surname>Tomaiuolo</surname>
<given-names>P.</given-names>
</name>
<name>
<surname>Castronovo</surname>
<given-names>P.</given-names>
</name>
<name>
<surname>Costa</surname>
<given-names>A.</given-names>
</name>
<name>
<surname>Verdecchia</surname>
<given-names>M.</given-names>
</name>
<etal/>
</person-group> (<year>2020</year>). <article-title>Appropriateness of array-CGH in the ADHD clinics: a comparative study</article-title>. <source>Genes Brain Behav.</source> <volume>19</volume> (<issue>6</issue>), <fpage>e12651</fpage>. <pub-id pub-id-type="doi">10.1111/gbb.12651</pub-id>
</citation>
</ref>
<ref id="B19">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Bachmann</surname>
<given-names>C. J.</given-names>
</name>
<name>
<surname>Philipsen</surname>
<given-names>A.</given-names>
</name>
<name>
<surname>Hoffmann</surname>
<given-names>F.</given-names>
</name>
</person-group> (<year>2017</year>). <article-title>ADHD in Germany: trends in diagnosis and pharmacotherapy</article-title>. <source>Dtsch. Arztebl Int.</source> <volume>114</volume> (<issue>9</issue>), <fpage>141</fpage>&#x2013;<lpage>148</lpage>. <pub-id pub-id-type="doi">10.3238/arztebl.2017.0141</pub-id>
</citation>
</ref>
<ref id="B20">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Bakry</surname>
<given-names>H.</given-names>
</name>
<name>
<surname>Alaiban</surname>
<given-names>R. A.</given-names>
</name>
<name>
<surname>Alkhyyat</surname>
<given-names>A. A.</given-names>
</name>
<name>
<surname>Alshamrani</surname>
<given-names>B. H.</given-names>
</name>
<name>
<surname>Naitah</surname>
<given-names>R. N.</given-names>
</name>
<name>
<surname>Almoayad</surname>
<given-names>F.</given-names>
</name>
</person-group> (<year>2023</year>). <article-title>Predictors of consanguinity marriage decision in Saudi Arabia: a pilot study</article-title>. <source>Healthc. (Basel)</source> <volume>11</volume> (<issue>13</issue>), <fpage>1925</fpage>. <pub-id pub-id-type="doi">10.3390/healthcare11131925</pub-id>
</citation>
</ref>
<ref id="B21">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Bawden</surname>
<given-names>D.</given-names>
</name>
<name>
<surname>Robinson</surname>
<given-names>L.</given-names>
</name>
</person-group> (<year>2009</year>). <article-title>The dark side of information: overload, anxiety and other paradoxes and pathologies</article-title>. <source>J. Inf. Sci.</source> <volume>35</volume> (<issue>2</issue>), <fpage>180</fpage>&#x2013;<lpage>191</lpage>. <pub-id pub-id-type="doi">10.1177/0165551508095781</pub-id>
</citation>
</ref>
<ref id="B22">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Bell</surname>
<given-names>C. C.</given-names>
</name>
</person-group> (<year>1994</year>). <article-title>DSM-IV: diagnostic and statistical manual of mental disorders</article-title>. <source>Jama</source> <volume>272</volume> (<issue>10</issue>), <fpage>828</fpage>&#x2013;<lpage>829</lpage>. <pub-id pub-id-type="doi">10.1001/jama.1994.03520100096046</pub-id>
</citation>
</ref>
<ref id="B23">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Bergwerff</surname>
<given-names>C. E.</given-names>
</name>
<name>
<surname>Luman</surname>
<given-names>M.</given-names>
</name>
<name>
<surname>Weeda</surname>
<given-names>W. D.</given-names>
</name>
<name>
<surname>Oosterlaan</surname>
<given-names>J.</given-names>
</name>
</person-group> (<year>2019</year>). <article-title>Neurocognitive profiles in children with ADHD and their predictive value for functional outcomes</article-title>. <source>J. Atten. Disord.</source> <volume>23</volume> (<issue>13</issue>), <fpage>1567</fpage>&#x2013;<lpage>1577</lpage>. <pub-id pub-id-type="doi">10.1177/1087054716688533</pub-id>
</citation>
</ref>
<ref id="B24">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Biederman</surname>
<given-names>J.</given-names>
</name>
<name>
<surname>Monuteaux</surname>
<given-names>M. C.</given-names>
</name>
<name>
<surname>Mick</surname>
<given-names>E.</given-names>
</name>
<name>
<surname>Spencer</surname>
<given-names>T.</given-names>
</name>
<name>
<surname>Wilens</surname>
<given-names>T. E.</given-names>
</name>
<name>
<surname>Silva</surname>
<given-names>J. M.</given-names>
</name>
<etal/>
</person-group> (<year>2006</year>). <article-title>Young adult outcome of attention deficit hyperactivity disorder: a controlled 10-year follow-up study</article-title>. <source>Psychol. Med.</source> <volume>36</volume> (<issue>2</issue>), <fpage>167</fpage>&#x2013;<lpage>179</lpage>. <pub-id pub-id-type="doi">10.1017/S0033291705006410</pub-id>
</citation>
</ref>
<ref id="B25">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Bobb</surname>
<given-names>A. J.</given-names>
</name>
<name>
<surname>Castellanos</surname>
<given-names>F. X.</given-names>
</name>
<name>
<surname>Addington</surname>
<given-names>A. M.</given-names>
</name>
<name>
<surname>Rapoport</surname>
<given-names>J. L.</given-names>
</name>
</person-group> (<year>2005</year>). <article-title>Molecular genetic studies of ADHD: 1991 to 2004</article-title>. <source>Am. J. Med. Genet. B Neuropsychiatr. Genet.</source> <volume>132B</volume> (<issue>1</issue>), <fpage>109</fpage>&#x2013;<lpage>125</lpage>.</citation>
</ref>
<ref id="B26">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Bonati</surname>
<given-names>M.</given-names>
</name>
<name>
<surname>Reale</surname>
<given-names>L.</given-names>
</name>
<name>
<surname>Zanetti</surname>
<given-names>M.</given-names>
</name>
<name>
<surname>Cartabia</surname>
<given-names>M.</given-names>
</name>
<name>
<surname>Fortinguerra</surname>
<given-names>F.</given-names>
</name>
<name>
<surname>Capovilla</surname>
<given-names>G.</given-names>
</name>
<etal/>
</person-group> (<year>2018</year>). <article-title>A regional ADHD center-based network project for the diagnosis and treatment of children and adolescents with ADHD</article-title>. <source>J. Atten. Disord.</source> <volume>22</volume> (<issue>12</issue>), <fpage>1173</fpage>&#x2013;<lpage>1184</lpage>. <pub-id pub-id-type="doi">10.1177/1087054715599573</pub-id>
</citation>
</ref>
<ref id="B27">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Bradshaw</surname>
<given-names>L. G.</given-names>
</name>
<name>
<surname>Kamal</surname>
<given-names>M.</given-names>
</name>
</person-group> (<year>2017</year>). <article-title>Prevalence of ADHD in Qatari school-age children</article-title>. <source>J. Atten. Disord.</source> <volume>21</volume> (<issue>5</issue>), <fpage>442</fpage>&#x2013;<lpage>449</lpage>. <pub-id pub-id-type="doi">10.1177/1087054713517545</pub-id>
</citation>
</ref>
<ref id="B28">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Buitelaar</surname>
<given-names>J.</given-names>
</name>
<name>
<surname>B&#xf6;lte</surname>
<given-names>S.</given-names>
</name>
<name>
<surname>Brandeis</surname>
<given-names>D.</given-names>
</name>
<name>
<surname>Caye</surname>
<given-names>A.</given-names>
</name>
<name>
<surname>Christmann</surname>
<given-names>N.</given-names>
</name>
<name>
<surname>Cortese</surname>
<given-names>S.</given-names>
</name>
<etal/>
</person-group> (<year>2022</year>). <article-title>Toward precision medicine in ADHD</article-title>. <source>Front. Behav. Neurosci.</source> <volume>16</volume>, <fpage>900981</fpage>. <pub-id pub-id-type="doi">10.3389/fnbeh.2022.900981</pub-id>
</citation>
</ref>
<ref id="B29">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Burd</surname>
<given-names>L.</given-names>
</name>
<name>
<surname>Kerbeshian</surname>
<given-names>J.</given-names>
</name>
</person-group> (<year>1988</year>). <article-title>Historical roots of ADHD</article-title>. <source>J. Am. Acad. Child. Adolesc. Psychiatry</source> <volume>27</volume> (<issue>2</issue>), <fpage>262</fpage>. <pub-id pub-id-type="doi">10.1097/00004583-198803000-00029</pub-id>
</citation>
</ref>
<ref id="B30">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Cani&#xeb;ls</surname>
<given-names>M. C.</given-names>
</name>
<name>
<surname>Semeijn</surname>
<given-names>J. H.</given-names>
</name>
<name>
<surname>Renders</surname>
<given-names>I. H.</given-names>
</name>
</person-group> (<year>2018</year>). <article-title>Mind the mindset! The interaction of proactive personality, transformational leadership and growth mindset for engagement at work</article-title>. <source>Career Dev. Int.</source> <volume>23</volume> (<issue>1</issue>), <fpage>48</fpage>&#x2013;<lpage>66</lpage>. <pub-id pub-id-type="doi">10.1108/cdi-11-2016-0194</pub-id>
</citation>
</ref>
<ref id="B31">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Castellanos</surname>
<given-names>F. X.</given-names>
</name>
<name>
<surname>Lee</surname>
<given-names>P. P.</given-names>
</name>
<name>
<surname>Sharp</surname>
<given-names>W.</given-names>
</name>
<name>
<surname>Jeffries</surname>
<given-names>N. O.</given-names>
</name>
<name>
<surname>Greenstein</surname>
<given-names>D. K.</given-names>
</name>
<name>
<surname>Clasen</surname>
<given-names>L. S.</given-names>
</name>
<etal/>
</person-group> (<year>2002</year>). <article-title>Developmental trajectories of brain volume abnormalities in children and adolescents with attention-deficit/hyperactivity disorder</article-title>. <source>JAMA</source> <volume>288</volume> (<issue>14</issue>), <fpage>1740</fpage>&#x2013;<lpage>1748</lpage>. <pub-id pub-id-type="doi">10.1001/jama.288.14.1740</pub-id>
</citation>
</ref>
<ref id="B32">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Castellanos</surname>
<given-names>F. X.</given-names>
</name>
<name>
<surname>Sonuga-Barke</surname>
<given-names>E. J.</given-names>
</name>
<name>
<surname>Milham</surname>
<given-names>M. P.</given-names>
</name>
<name>
<surname>Tannock</surname>
<given-names>R.</given-names>
</name>
</person-group> (<year>2006</year>). <article-title>Characterizing cognition in ADHD: beyond executive dysfunction</article-title>. <source>Trends Cogn. Sci.</source> <volume>10</volume> (<issue>3</issue>), <fpage>117</fpage>&#x2013;<lpage>123</lpage>. <pub-id pub-id-type="doi">10.1016/j.tics.2006.01.011</pub-id>
</citation>
</ref>
<ref id="B33">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Castellanos</surname>
<given-names>F. X.</given-names>
</name>
<name>
<surname>Tannock</surname>
<given-names>R.</given-names>
</name>
</person-group> (<year>2002</year>). <article-title>Neuroscience of attention-deficit/hyperactivity disorder: the search for endophenotypes</article-title>. <source>Nat. Rev. Neurosci.</source> <volume>3</volume> (<issue>8</issue>), <fpage>617</fpage>&#x2013;<lpage>628</lpage>. <pub-id pub-id-type="doi">10.1038/nrn896</pub-id>
</citation>
</ref>
<ref id="B34">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Chan</surname>
<given-names>M. F.</given-names>
</name>
<name>
<surname>Al Balushi</surname>
<given-names>R.</given-names>
</name>
<name>
<surname>Al Falahi</surname>
<given-names>M.</given-names>
</name>
<name>
<surname>Mahadevan</surname>
<given-names>S.</given-names>
</name>
<name>
<surname>Al Saadoon</surname>
<given-names>M.</given-names>
</name>
<name>
<surname>Al-Adawi</surname>
<given-names>S.</given-names>
</name>
</person-group> (<year>2021</year>). <article-title>Child and adolescent mental health disorders in the GCC: a systematic review and meta-analysis</article-title>. <source>Int. J. Pediatr. Adolesc. Med.</source> <volume>8</volume> (<issue>3</issue>), <fpage>134</fpage>&#x2013;<lpage>145</lpage>. <pub-id pub-id-type="doi">10.1016/j.ijpam.2021.04.002</pub-id>
</citation>
</ref>
<ref id="B35">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Chen</surname>
<given-names>W.</given-names>
</name>
<name>
<surname>Zhou</surname>
<given-names>K.</given-names>
</name>
<name>
<surname>Sham</surname>
<given-names>P.</given-names>
</name>
<name>
<surname>Franke</surname>
<given-names>B.</given-names>
</name>
<name>
<surname>Kuntsi</surname>
<given-names>J.</given-names>
</name>
<name>
<surname>Campbell</surname>
<given-names>D.</given-names>
</name>
<etal/>
</person-group> (<year>2008</year>). <article-title>DSM-IV combined type ADHD shows familial association with sibling trait scores: a sampling strategy for QTL linkage</article-title>. <source>Am. J. Med. Genet. B Neuropsychiatr. Genet.</source> <volume>147B</volume> (<issue>8</issue>), <fpage>1450</fpage>&#x2013;<lpage>1460</lpage>. <pub-id pub-id-type="doi">10.1002/ajmg.b.30672</pub-id>
</citation>
</ref>
<ref id="B36">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Claussen</surname>
<given-names>A. H.</given-names>
</name>
<name>
<surname>Holbrook</surname>
<given-names>J. R.</given-names>
</name>
<name>
<surname>Hutchins</surname>
<given-names>H. J.</given-names>
</name>
<name>
<surname>Robinson</surname>
<given-names>L. R.</given-names>
</name>
<name>
<surname>Bloomfield</surname>
<given-names>J.</given-names>
</name>
<name>
<surname>Meng</surname>
<given-names>L.</given-names>
</name>
<etal/>
</person-group> (<year>2022</year>). <article-title>All in the family? A systematic review and meta-analysis of parenting and family environment as risk factors for attention-deficit/hyperactivity disorder (ADHD) in children</article-title>. <source>Prev. Sci.</source> <volume>25</volume>, <fpage>249</fpage>&#x2013;<lpage>271</lpage>. <pub-id pub-id-type="doi">10.1007/s11121-022-01358-4</pub-id>
</citation>
</ref>
<ref id="B37">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Coghill</surname>
<given-names>D.</given-names>
</name>
</person-group> (<year>2017</year>). <article-title>Organisation of services for managing ADHD</article-title>. <source>Epidemiol. Psychiatric Sci.</source> <volume>26</volume> (<issue>5</issue>), <fpage>453</fpage>&#x2013;<lpage>458</lpage>. <pub-id pub-id-type="doi">10.1017/S2045796016000937</pub-id>
</citation>
</ref>
<ref id="B38">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Coghill</surname>
<given-names>D. R.</given-names>
</name>
<name>
<surname>Seth</surname>
<given-names>S.</given-names>
</name>
<name>
<surname>Matthews</surname>
<given-names>K.</given-names>
</name>
</person-group> (<year>2014</year>). <article-title>A comprehensive assessment of memory, delay aversion, timing, inhibition, decision making and variability in attention deficit hyperactivity disorder: advancing beyond the three-pathway models</article-title>. <source>Psychol. Med.</source> <volume>44</volume> (<issue>9</issue>), <fpage>1989</fpage>&#x2013;<lpage>2001</lpage>. <pub-id pub-id-type="doi">10.1017/S0033291713002547</pub-id>
</citation>
</ref>
<ref id="B39">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Cook</surname>
<given-names>E. H.</given-names>
<suffix>Jr.</suffix>
</name>
<name>
<surname>Stein</surname>
<given-names>M. A.</given-names>
</name>
<name>
<surname>Krasowski</surname>
<given-names>M. D.</given-names>
</name>
<name>
<surname>Cox</surname>
<given-names>N. J.</given-names>
</name>
<name>
<surname>Olkon</surname>
<given-names>D. M.</given-names>
</name>
<name>
<surname>Kieffer</surname>
<given-names>J. E.</given-names>
</name>
<etal/>
</person-group> (<year>1995</year>). <article-title>Association of attention-deficit disorder and the dopamine transporter gene</article-title>. <source>Am. J. Hum. Genet.</source> <volume>56</volume> (<issue>4</issue>), <fpage>993</fpage>&#x2013;<lpage>998</lpage>.</citation>
</ref>
<ref id="B40">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Craig</surname>
<given-names>F.</given-names>
</name>
<name>
<surname>Savino</surname>
<given-names>R.</given-names>
</name>
<name>
<surname>Fanizza</surname>
<given-names>I.</given-names>
</name>
<name>
<surname>Lucarelli</surname>
<given-names>E.</given-names>
</name>
<name>
<surname>Russo</surname>
<given-names>L.</given-names>
</name>
<name>
<surname>Trabacca</surname>
<given-names>A.</given-names>
</name>
</person-group> (<year>2020</year>). <article-title>A systematic review of coping strategies in parents of children with attention deficit hyperactivity disorder (ADHD)</article-title>. <source>Res. Dev. Disabil.</source> <volume>98</volume>, <fpage>103571</fpage>. <pub-id pub-id-type="doi">10.1016/j.ridd.2020.103571</pub-id>
</citation>
</ref>
<ref id="B41">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Curatolo</surname>
<given-names>P.</given-names>
</name>
<name>
<surname>D&#x2019;Agati</surname>
<given-names>E.</given-names>
</name>
<name>
<surname>Moavero</surname>
<given-names>R.</given-names>
</name>
</person-group> (<year>2010</year>). <article-title>The neurobiological basis of ADHD</article-title>. <source>Ital. J. Pediatr.</source> <volume>36</volume> (<issue>1</issue>), <fpage>79</fpage>. <pub-id pub-id-type="doi">10.1186/1824-7288-36-79</pub-id>
</citation>
</ref>
<ref id="B42">
<citation citation-type="book">
<person-group person-group-type="author">
<name>
<surname>Dalton</surname>
<given-names>N. S.</given-names>
</name>
</person-group> (<year>2013</year>). <article-title>Neurodiversity and HCI</article-title>. in <source>CHI 13 Extended abstracts on human factors in computing systems</source>, <fpage>2295</fpage>&#x2013;<lpage>2304</lpage>.</citation>
</ref>
<ref id="B43">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Del Campo</surname>
<given-names>N.</given-names>
</name>
<name>
<surname>Chamberlain</surname>
<given-names>S. R.</given-names>
</name>
<name>
<surname>Sahakian</surname>
<given-names>B. J.</given-names>
</name>
<name>
<surname>Robbins</surname>
<given-names>T. W.</given-names>
</name>
</person-group> (<year>2011</year>). <article-title>The roles of dopamine and noradrenaline in the pathophysiology and treatment of attention-deficit/hyperactivity disorder</article-title>. <source>Biol. Psychiatry</source> <volume>69</volume> (<issue>12</issue>), <fpage>e145</fpage>&#x2013;<lpage>e157</lpage>. <pub-id pub-id-type="doi">10.1016/j.biopsych.2011.02.036</pub-id>
</citation>
</ref>
<ref id="B44">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Demontis</surname>
<given-names>D.</given-names>
</name>
<name>
<surname>Walters</surname>
<given-names>G. B.</given-names>
</name>
<name>
<surname>Athanasiadis</surname>
<given-names>G.</given-names>
</name>
<name>
<surname>Walters</surname>
<given-names>R.</given-names>
</name>
<name>
<surname>Therrien</surname>
<given-names>K.</given-names>
</name>
<name>
<surname>Nielsen</surname>
<given-names>T. T.</given-names>
</name>
<etal/>
</person-group> (<year>2023</year>). <article-title>Genome-wide analyses of ADHD identify 27 risk loci, refine the genetic architecture and implicate several cognitive domains</article-title>. <source>Nat. Genet.</source> <volume>55</volume> (<issue>2</issue>), <fpage>198</fpage>&#x2013;<lpage>208</lpage>. <pub-id pub-id-type="doi">10.1038/s41588-022-01285-8</pub-id>
</citation>
</ref>
<ref id="B45">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Demontis</surname>
<given-names>D.</given-names>
</name>
<name>
<surname>Walters</surname>
<given-names>R. K.</given-names>
</name>
<name>
<surname>Martin</surname>
<given-names>J.</given-names>
</name>
<name>
<surname>Mattheisen</surname>
<given-names>M.</given-names>
</name>
<name>
<surname>Als</surname>
<given-names>T. D.</given-names>
</name>
<name>
<surname>Agerbo</surname>
<given-names>E.</given-names>
</name>
<etal/>
</person-group> (<year>2019</year>). <article-title>Discovery of the first genome-wide significant risk loci for attention deficit/hyperactivity disorder</article-title>. <source>Nat. Genet.</source> <volume>51</volume> (<issue>1</issue>), <fpage>63</fpage>&#x2013;<lpage>75</lpage>. <pub-id pub-id-type="doi">10.1038/s41588-018-0269-7</pub-id>
</citation>
</ref>
<ref id="B46">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Dougnon</surname>
<given-names>G.</given-names>
</name>
<name>
<surname>Matsui</surname>
<given-names>H.</given-names>
</name>
</person-group> (<year>2022</year>). <article-title>Modelling autism spectrum disorder (ASD) and attention-deficit/hyperactivity disorder (ADHD) using mice and zebrafish</article-title>. <source>Int. J. Mol. Sci.</source> <volume>23</volume> (<issue>14</issue>), <fpage>7550</fpage>. <pub-id pub-id-type="doi">10.3390/ijms23147550</pub-id>
</citation>
</ref>
<ref id="B47">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Drechsler</surname>
<given-names>R.</given-names>
</name>
<name>
<surname>Brem</surname>
<given-names>S.</given-names>
</name>
<name>
<surname>Brandeis</surname>
<given-names>D.</given-names>
</name>
<name>
<surname>Grunblatt</surname>
<given-names>E.</given-names>
</name>
<name>
<surname>Berger</surname>
<given-names>G.</given-names>
</name>
<name>
<surname>Walitza</surname>
<given-names>S.</given-names>
</name>
</person-group> (<year>2020</year>). <article-title>ADHD: current concepts and treatments in children and adolescents</article-title>. <source>Neuropediatrics</source> <volume>51</volume> (<issue>5</issue>), <fpage>315</fpage>&#x2013;<lpage>335</lpage>. <pub-id pub-id-type="doi">10.1055/s-0040-1701658</pub-id>
</citation>
</ref>
<ref id="B48">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Fair</surname>
<given-names>D. A.</given-names>
</name>
<name>
<surname>Bathula</surname>
<given-names>D.</given-names>
</name>
<name>
<surname>Nikolas</surname>
<given-names>M. A.</given-names>
</name>
<name>
<surname>Nigg</surname>
<given-names>J. T.</given-names>
</name>
</person-group> (<year>2012</year>). <article-title>Distinct neuropsychological subgroups in typically developing youth inform heterogeneity in children with ADHD</article-title>. <source>Proc. Natl. Acad. Sci. U. S. A.</source> <volume>109</volume> (<issue>17</issue>), <fpage>6769</fpage>&#x2013;<lpage>6774</lpage>. <pub-id pub-id-type="doi">10.1073/pnas.1115365109</pub-id>
</citation>
</ref>
<ref id="B49">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Farah</surname>
<given-names>L. G.</given-names>
</name>
<name>
<surname>Fayyad</surname>
<given-names>J. A.</given-names>
</name>
<name>
<surname>Eapen</surname>
<given-names>V.</given-names>
</name>
<name>
<surname>Cassir</surname>
<given-names>Y.</given-names>
</name>
<name>
<surname>Salamoun</surname>
<given-names>M. M.</given-names>
</name>
<name>
<surname>Tabet</surname>
<given-names>C. C.</given-names>
</name>
<etal/>
</person-group> (<year>2009</year>). <article-title>ADHD in the Arab world: a review of epidemiologic studies</article-title>. <source>J. Atten. Disord.</source> <volume>13</volume> (<issue>3</issue>), <fpage>211</fpage>&#x2013;<lpage>222</lpage>. <pub-id pub-id-type="doi">10.1177/1087054708325976</pub-id>
</citation>
</ref>
<ref id="B50">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Faraone</surname>
<given-names>S. V.</given-names>
</name>
</person-group> (<year>2000</year>). <article-title>Genetics of childhood disorders: XX. ADHD, Part 4: is ADHD genetically heterogeneous?</article-title> <source>J. Am. Acad. Child Adolesc. Psychiatry</source> <volume>39</volume> (<issue>11</issue>), <fpage>1455</fpage>&#x2013;<lpage>1457</lpage>. <pub-id pub-id-type="doi">10.1097/00004583-200011000-00022</pub-id>
</citation>
</ref>
<ref id="B51">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Faraone</surname>
<given-names>S. V.</given-names>
</name>
<name>
<surname>Larsson</surname>
<given-names>H.</given-names>
</name>
</person-group> (<year>2019</year>). <article-title>Genetics of attention deficit hyperactivity disorder</article-title>. <source>Mol. Psychiatry</source> <volume>24</volume> (<issue>4</issue>), <fpage>562</fpage>&#x2013;<lpage>575</lpage>. <pub-id pub-id-type="doi">10.1038/s41380-018-0070-0</pub-id>
</citation>
</ref>
<ref id="B52">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Fatima</surname>
<given-names>W.</given-names>
</name>
<name>
<surname>Ahmad</surname>
<given-names>L. M.</given-names>
</name>
</person-group> (<year>2018</year>). <article-title>Prevalence of disordered eating attitudes among adolescent girls in Arar City, Kingdom of Saudi Arabia</article-title>. <source>Health Psychol. Res.</source> <volume>6</volume> (<issue>1</issue>), <fpage>7444</fpage>. <pub-id pub-id-type="doi">10.4081/hpr.2018.7444</pub-id>
</citation>
</ref>
<ref id="B53">
<citation citation-type="web">
<collab>FDA</collab> (<year>2023</year>). <article-title>Treating and dealing with ADHD</article-title>. <comment>Available at: <ext-link ext-link-type="uri" xlink:href="https://www.fda.gov/consumers/consumer-updates/treating-and-dealing-adhd">https://www.fda.gov/consumers/consumer-updates/treating-and-dealing-adhd</ext-link> (Accessed October 29, 2023)</comment>.</citation>
</ref>
<ref id="B54">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Ferguson</surname>
<given-names>J. H.</given-names>
</name>
</person-group> (<year>2000</year>). <article-title>National institutes of health consensus development conference statement: diagnosis and treatment of attention-deficit/hyperactivity disorder (ADHD)</article-title>. <source>J. Am. Acad. Child Adolesc. Psychiatry</source> <volume>39</volume> (<issue>2</issue>), <fpage>182</fpage>&#x2013;<lpage>193</lpage>. <pub-id pub-id-type="doi">10.1097/00004583-200002000-00018</pub-id>
</citation>
</ref>
<ref id="B55">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Foreman</surname>
<given-names>D. M.</given-names>
</name>
</person-group> (<year>2006</year>). <article-title>Attention deficit hyperactivity disorder: legal and ethical aspects</article-title>. <source>Arch. Dis. Child.</source> <volume>91</volume> (<issue>2</issue>), <fpage>192</fpage>&#x2013;<lpage>194</lpage>. <pub-id pub-id-type="doi">10.1136/adc.2004.064576</pub-id>
</citation>
</ref>
<ref id="B56">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Franke</surname>
<given-names>B.</given-names>
</name>
<name>
<surname>Neale</surname>
<given-names>B. M.</given-names>
</name>
<name>
<surname>Faraone</surname>
<given-names>S. V.</given-names>
</name>
</person-group> (<year>2009</year>). <article-title>Genome-wide association studies in ADHD</article-title>. <source>Hum. Genet.</source> <volume>126</volume>, <fpage>13</fpage>&#x2013;<lpage>50</lpage>. <pub-id pub-id-type="doi">10.1007/s00439-009-0663-4</pub-id>
</citation>
</ref>
<ref id="B57">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Fredrickson</surname>
<given-names>B. L.</given-names>
</name>
</person-group> (<year>2000</year>). <article-title>Cultivating positive emotions to optimize health and well-being</article-title>. <source>Prev. Treat.</source> <volume>3</volume> (<issue>1</issue>), <fpage>1a</fpage>. <pub-id pub-id-type="doi">10.1037/1522-3736.3.1.31a</pub-id>
</citation>
</ref>
<ref id="B58">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Gehricke</surname>
<given-names>J. G.</given-names>
</name>
<name>
<surname>Kruggel</surname>
<given-names>F.</given-names>
</name>
<name>
<surname>Thampipop</surname>
<given-names>T.</given-names>
</name>
<name>
<surname>Alejo</surname>
<given-names>S. D.</given-names>
</name>
<name>
<surname>Tatos</surname>
<given-names>E.</given-names>
</name>
<name>
<surname>Fallon</surname>
<given-names>J.</given-names>
</name>
<etal/>
</person-group> (<year>2017</year>). <article-title>The brain anatomy of attention-deficit/hyperactivity disorder in young adults - a magnetic resonance imaging study</article-title>. <source>PLoS One</source> <volume>12</volume> (<issue>4</issue>), <fpage>e0175433</fpage>. <pub-id pub-id-type="doi">10.1371/journal.pone.0175433</pub-id>
</citation>
</ref>
<ref id="B59">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Gomez</surname>
<given-names>R.</given-names>
</name>
<name>
<surname>Gomez</surname>
<given-names>R. M.</given-names>
</name>
<name>
<surname>Winther</surname>
<given-names>J.</given-names>
</name>
<name>
<surname>Vance</surname>
<given-names>A.</given-names>
</name>
</person-group> (<year>2014</year>). <article-title>Latent profile analysis of working memory performance in a sample of children with ADHD</article-title>. <source>J. Abnorm Child. Psychol.</source> <volume>42</volume> (<issue>8</issue>), <fpage>1367</fpage>&#x2013;<lpage>1379</lpage>. <pub-id pub-id-type="doi">10.1007/s10802-014-9878-5</pub-id>
</citation>
</ref>
<ref id="B60">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Grimm</surname>
<given-names>O.</given-names>
</name>
<name>
<surname>Kittel-Schneider</surname>
<given-names>S.</given-names>
</name>
<name>
<surname>Reif</surname>
<given-names>A.</given-names>
</name>
</person-group> (<year>2018</year>). <article-title>Recent developments in the genetics of attention-deficit hyperactivity disorder</article-title>. <source>Psychiatry Clin. Neurosci.</source> <volume>72</volume> (<issue>9</issue>), <fpage>654</fpage>&#x2013;<lpage>672</lpage>. <pub-id pub-id-type="doi">10.1111/pcn.12673</pub-id>
</citation>
</ref>
<ref id="B61">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Hamamy</surname>
<given-names>H.</given-names>
</name>
</person-group> (<year>2012</year>). <article-title>Consanguineous marriages: preconception consultation in primary health care settings: preconception consultation in primary health care settings</article-title>. <source>J. Community Genet.</source> <volume>3</volume> (<issue>3</issue>), <fpage>185</fpage>&#x2013;<lpage>192</lpage>. <pub-id pub-id-type="doi">10.1007/s12687-011-0072-y</pub-id>
</citation>
</ref>
<ref id="B62">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Hawi</surname>
<given-names>Z.</given-names>
</name>
<name>
<surname>Cummins</surname>
<given-names>T. D.</given-names>
</name>
<name>
<surname>Tong</surname>
<given-names>J.</given-names>
</name>
<name>
<surname>Johnson</surname>
<given-names>B.</given-names>
</name>
<name>
<surname>Lau</surname>
<given-names>R.</given-names>
</name>
<name>
<surname>Samarrai</surname>
<given-names>W.</given-names>
</name>
<etal/>
</person-group> (<year>2015</year>). <article-title>The molecular genetic architecture of attention deficit hyperactivity disorder</article-title>. <source>Mol. Psychiatry</source> <volume>20</volume> (<issue>3</issue>), <fpage>289</fpage>&#x2013;<lpage>297</lpage>. <pub-id pub-id-type="doi">10.1038/mp.2014.183</pub-id>
</citation>
</ref>
<ref id="B63">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Hawsawi</surname>
<given-names>Y. M.</given-names>
</name>
<name>
<surname>Al-Numair</surname>
<given-names>N. S.</given-names>
</name>
<name>
<surname>Sobahy</surname>
<given-names>T. M.</given-names>
</name>
<name>
<surname>Al-Ajmi</surname>
<given-names>A. M.</given-names>
</name>
<name>
<surname>Al-Harbi</surname>
<given-names>R. M.</given-names>
</name>
<name>
<surname>Baghdadi</surname>
<given-names>M. A.</given-names>
</name>
<etal/>
</person-group> (<year>2019</year>). <article-title>The role of BRCA1/2 in hereditary and familial breast and ovarian cancers</article-title>. <source>Mol. Genet. Genomic Med.</source> <volume>7</volume> (<issue>9</issue>), <fpage>e879</fpage>. <pub-id pub-id-type="doi">10.1002/mgg3.879</pub-id>
</citation>
</ref>
<ref id="B64">
<citation citation-type="book">
<person-group person-group-type="author">
<name>
<surname>Hayashibara</surname>
<given-names>E.</given-names>
</name>
<name>
<surname>Savickaite</surname>
<given-names>S.</given-names>
</name>
<name>
<surname>Simmons</surname>
<given-names>D.</given-names>
</name>
</person-group> (<year>2023</year>). <source>Creativity and neurodiversity: towards an inclusive creativity measure for autism and ADHD</source>.</citation>
</ref>
<ref id="B65">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Jackson</surname>
<given-names>M.</given-names>
</name>
<name>
<surname>Marks</surname>
<given-names>L.</given-names>
</name>
<name>
<surname>May</surname>
<given-names>G. H. W.</given-names>
</name>
<name>
<surname>Wilson</surname>
<given-names>J. B.</given-names>
</name>
</person-group> (<year>2018</year>). <article-title>The genetic basis of disease</article-title>. <source>Essays Biochem.</source> <volume>62</volume> (<issue>5</issue>), <fpage>643</fpage>&#x2013;<lpage>723</lpage>. <pub-id pub-id-type="doi">10.1042/EBC20170053</pub-id>
</citation>
</ref>
<ref id="B66">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Jenahi</surname>
<given-names>E.</given-names>
</name>
<name>
<surname>Khalil</surname>
<given-names>M. S.</given-names>
</name>
<name>
<surname>Bella</surname>
<given-names>H.</given-names>
</name>
</person-group> (<year>2012</year>). <article-title>Prevalence of attention deficit hyperactivity symptoms in female schoolchildren in Saudi Arabia</article-title>. <source>Ann. Saudi Med.</source> <volume>32</volume> (<issue>5</issue>), <fpage>462</fpage>&#x2013;<lpage>468</lpage>. <pub-id pub-id-type="doi">10.5144/0256-4947.2012.462</pub-id>
</citation>
</ref>
<ref id="B67">
<citation citation-type="book">
<person-group person-group-type="author">
<name>
<surname>Kemper</surname>
<given-names>A. R.</given-names>
</name>
<name>
<surname>Maslow</surname>
<given-names>G. R.</given-names>
</name>
<name>
<surname>Hill</surname>
<given-names>S.</given-names>
</name>
<name>
<surname>Namdari</surname>
<given-names>B.</given-names>
</name>
<name>
<surname>NM</surname>
<given-names>A. L.</given-names>
</name>
<name>
<surname>Goode</surname>
<given-names>A. P.</given-names>
</name>
<etal/>
</person-group> (<year>2018</year>). <source>Attention deficit hyperactivity disorder: diagnosis and treatment in children and adolescents</source>.</citation>
</ref>
<ref id="B68">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Khayat</surname>
<given-names>A. M.</given-names>
</name>
<name>
<surname>Alshareef</surname>
<given-names>B. G.</given-names>
</name>
<name>
<surname>Alharbi</surname>
<given-names>S. F.</given-names>
</name>
<name>
<surname>AlZahrani</surname>
<given-names>M. M.</given-names>
</name>
<name>
<surname>Alshangity</surname>
<given-names>B. A.</given-names>
</name>
<name>
<surname>Tashkandi</surname>
<given-names>N. F.</given-names>
</name>
</person-group> (<year>2024</year>). <article-title>Consanguineous marriage and its association with genetic disorders in Saudi Arabia: a review</article-title>. <source>Cureus</source> <volume>16</volume> (<issue>2</issue>), <fpage>e53888</fpage>. <pub-id pub-id-type="doi">10.7759/cureus.53888</pub-id>
</citation>
</ref>
<ref id="B69">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Kim</surname>
<given-names>D.</given-names>
</name>
<name>
<surname>Yadav</surname>
<given-names>D.</given-names>
</name>
<name>
<surname>Song</surname>
<given-names>M.</given-names>
</name>
</person-group> (<year>2024</year>). <article-title>An updated review on animal models to study attention-deficit hyperactivity disorder</article-title>. <source>Transl. Psychiatry</source> <volume>14</volume> (<issue>1</issue>), <fpage>187</fpage>. <pub-id pub-id-type="doi">10.1038/s41398-024-02893-0</pub-id>
</citation>
</ref>
<ref id="B70">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Kim</surname>
<given-names>J. H.</given-names>
</name>
<name>
<surname>Kim</surname>
<given-names>J. Y.</given-names>
</name>
<name>
<surname>Lee</surname>
<given-names>J.</given-names>
</name>
<name>
<surname>Jeong</surname>
<given-names>G. H.</given-names>
</name>
<name>
<surname>Lee</surname>
<given-names>E.</given-names>
</name>
<name>
<surname>Lee</surname>
<given-names>S.</given-names>
</name>
<etal/>
</person-group> (<year>2020</year>). <article-title>Environmental risk factors, protective factors, and peripheral biomarkers for ADHD: an umbrella review</article-title>. <source>Lancet Psychiatry</source> <volume>7</volume> (<issue>11</issue>), <fpage>955</fpage>&#x2013;<lpage>970</lpage>. <pub-id pub-id-type="doi">10.1016/S2215-0366(20)30312-6</pub-id>
</citation>
</ref>
<ref id="B71">
<citation citation-type="book">
<person-group person-group-type="author">
<name>
<surname>Kirby</surname>
<given-names>A.</given-names>
</name>
<name>
<surname>Smith</surname>
<given-names>T.</given-names>
</name>
</person-group> (<year>2021</year>). <source>Neurodiversity at work: drive innovation, performance and productivity with a neurodiverse workforce</source>. <publisher-loc>United Kingdom</publisher-loc>: <publisher-name>Kogan Page Publishers</publisher-name>.</citation>
</ref>
<ref id="B72">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Kirley</surname>
<given-names>A.</given-names>
</name>
<name>
<surname>Lowe</surname>
<given-names>N.</given-names>
</name>
<name>
<surname>Hawi</surname>
<given-names>Z.</given-names>
</name>
<name>
<surname>Mullins</surname>
<given-names>C.</given-names>
</name>
<name>
<surname>Daly</surname>
<given-names>G.</given-names>
</name>
<name>
<surname>Waldman</surname>
<given-names>I.</given-names>
</name>
<etal/>
</person-group> (<year>2003</year>). <article-title>Association of the 480 bp DAT1 allele with methylphenidate response in a sample of Irish children with ADHD</article-title>. <source>Am. J. Med. Genet. B Neuropsychiatr. Genet.</source> <volume>121</volume> (<issue>1</issue>), <fpage>50</fpage>&#x2013;<lpage>54</lpage>. <pub-id pub-id-type="doi">10.1002/ajmg.b.20071</pub-id>
</citation>
</ref>
<ref id="B73">
<citation citation-type="book">
<person-group person-group-type="author">
<name>
<surname>Kobe</surname>
<given-names>R.</given-names>
</name>
</person-group> (<year>2023</year>). <source>Mental health and wellbeing</source>. <publisher-name>Richmond Kobe</publisher-name>.</citation>
</ref>
<ref id="B74">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Konrad</surname>
<given-names>A.</given-names>
</name>
<name>
<surname>Dielentheis</surname>
<given-names>T. F.</given-names>
</name>
<name>
<surname>El Masri</surname>
<given-names>D.</given-names>
</name>
<name>
<surname>Dellani</surname>
<given-names>P. R.</given-names>
</name>
<name>
<surname>Stoeter</surname>
<given-names>P.</given-names>
</name>
<name>
<surname>Vucurevic</surname>
<given-names>G.</given-names>
</name>
<etal/>
</person-group> (<year>2012</year>). <article-title>White matter abnormalities and their impact on attentional performance in adult attention-deficit/hyperactivity disorder</article-title>. <source>Eur. Arch. Psychiatry Clin. Neurosci.</source> <volume>262</volume> (<issue>4</issue>), <fpage>351</fpage>&#x2013;<lpage>360</lpage>. <pub-id pub-id-type="doi">10.1007/s00406-011-0251-1</pub-id>
</citation>
</ref>
<ref id="B75">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Lange</surname>
<given-names>K. W.</given-names>
</name>
<name>
<surname>Reichl</surname>
<given-names>S.</given-names>
</name>
<name>
<surname>Lange</surname>
<given-names>K. M.</given-names>
</name>
<name>
<surname>Tucha</surname>
<given-names>L.</given-names>
</name>
<name>
<surname>Tucha</surname>
<given-names>O.</given-names>
</name>
</person-group> (<year>2010</year>). <article-title>The history of attention deficit hyperactivity disorder</article-title>. <source>Atten. Defic. Hyperact. Disord.</source> <volume>2</volume> (<issue>4</issue>), <fpage>241</fpage>&#x2013;<lpage>255</lpage>. <pub-id pub-id-type="doi">10.1007/s12402-010-0045-8</pub-id>
</citation>
</ref>
<ref id="B76">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Larsson</surname>
<given-names>H.</given-names>
</name>
<name>
<surname>Anckarsater</surname>
<given-names>H.</given-names>
</name>
<name>
<surname>Rastam</surname>
<given-names>M.</given-names>
</name>
<name>
<surname>Chang</surname>
<given-names>Z.</given-names>
</name>
<name>
<surname>Lichtenstein</surname>
<given-names>P.</given-names>
</name>
</person-group> (<year>2012</year>). <article-title>Childhood attention-deficit hyperactivity disorder as an extreme of a continuous trait: a quantitative genetic study of 8,500 twin pairs</article-title>. <source>J. Child. Psychol. Psychiatry</source> <volume>53</volume> (<issue>1</issue>), <fpage>73</fpage>&#x2013;<lpage>80</lpage>. <pub-id pub-id-type="doi">10.1111/j.1469-7610.2011.02467.x</pub-id>
</citation>
</ref>
<ref id="B77">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Larsson</surname>
<given-names>H.</given-names>
</name>
<name>
<surname>Lichtenstein</surname>
<given-names>P.</given-names>
</name>
<name>
<surname>Larsson</surname>
<given-names>J. O.</given-names>
</name>
</person-group> (<year>2006</year>). <article-title>Genetic contributions to the development of ADHD subtypes from childhood to adolescence</article-title>. <source>J. Am. Acad. Child. Adolesc. Psychiatry</source> <volume>45</volume> (<issue>8</issue>), <fpage>973</fpage>&#x2013;<lpage>981</lpage>. <pub-id pub-id-type="doi">10.1097/01.chi.0000222787.57100.d8</pub-id>
</citation>
</ref>
<ref id="B78">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Lasky-Su</surname>
<given-names>J.</given-names>
</name>
<name>
<surname>Neale</surname>
<given-names>B. M.</given-names>
</name>
<name>
<surname>Franke</surname>
<given-names>B.</given-names>
</name>
<name>
<surname>Anney</surname>
<given-names>R. J.</given-names>
</name>
<name>
<surname>Zhou</surname>
<given-names>K.</given-names>
</name>
<name>
<surname>Maller</surname>
<given-names>J. B.</given-names>
</name>
<etal/>
</person-group> (<year>2008</year>). <article-title>Genome-wide association scan of quantitative traits for attention deficit hyperactivity disorder identifies novel associations and confirms candidate gene associations</article-title>. <source>Am. J. Med. Genet. B Neuropsychiatr. Genet.</source> <volume>147B</volume> (<issue>8</issue>), <fpage>1345</fpage>&#x2013;<lpage>1354</lpage>. <pub-id pub-id-type="doi">10.1002/ajmg.b.30867</pub-id>
</citation>
</ref>
<ref id="B79">
<citation citation-type="book">
<person-group person-group-type="author">
<name>
<surname>Lazar</surname>
<given-names>J.</given-names>
</name>
<name>
<surname>Stein</surname>
<given-names>M. A.</given-names>
</name>
</person-group> (<year>2017</year>). <source>Disability, human rights, and information technology</source>. <publisher-name>University of Pennsylvania Press</publisher-name>.</citation>
</ref>
<ref id="B80">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Li</surname>
<given-names>Q.</given-names>
</name>
<name>
<surname>Lu</surname>
<given-names>G.</given-names>
</name>
<name>
<surname>Antonio</surname>
<given-names>G. E.</given-names>
</name>
<name>
<surname>Mak</surname>
<given-names>Y. T.</given-names>
</name>
<name>
<surname>Rudd</surname>
<given-names>J. A.</given-names>
</name>
<name>
<surname>Fan</surname>
<given-names>M.</given-names>
</name>
<etal/>
</person-group> (<year>2007</year>). <article-title>The usefulness of the spontaneously hypertensive rat to model attention-deficit/hyperactivity disorder (ADHD) may be explained by the differential expression of dopamine-related genes in the brain</article-title>. <source>Neurochem. Int.</source> <volume>50</volume> (<issue>6</issue>), <fpage>848</fpage>&#x2013;<lpage>857</lpage>. <pub-id pub-id-type="doi">10.1016/j.neuint.2007.02.005</pub-id>
</citation>
</ref>
<ref id="B81">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Lima Lde</surname>
<given-names>A.</given-names>
</name>
<name>
<surname>Feio-dos-Santos</surname>
<given-names>A. C.</given-names>
</name>
<name>
<surname>Belangero</surname>
<given-names>S. I.</given-names>
</name>
<name>
<surname>Gadelha</surname>
<given-names>A.</given-names>
</name>
<name>
<surname>Bressan</surname>
<given-names>R. A.</given-names>
</name>
<name>
<surname>Salum</surname>
<given-names>G. A.</given-names>
</name>
<etal/>
</person-group> (<year>2016</year>). <article-title>An integrative approach to investigate the respective roles of single-nucleotide variants and copy-number variants in Attention-Deficit/Hyperactivity Disorder</article-title>. <source>Sci. Rep.</source> <volume>6</volume>, <fpage>22851</fpage>. <pub-id pub-id-type="doi">10.1038/srep22851</pub-id>
</citation>
</ref>
<ref id="B82">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Mahrous</surname>
<given-names>N. N.</given-names>
</name>
<name>
<surname>Jamous</surname>
<given-names>Y. F.</given-names>
</name>
<name>
<surname>Almatrafi</surname>
<given-names>A. M.</given-names>
</name>
<name>
<surname>Fallatah</surname>
<given-names>D. I.</given-names>
</name>
<name>
<surname>Theyab</surname>
<given-names>A.</given-names>
</name>
<name>
<surname>Alanati</surname>
<given-names>B. H.</given-names>
</name>
<etal/>
</person-group> (<year>2023</year>). <article-title>A current landscape on Alport syndrome cases: characterization, therapy and management perspectives</article-title>. <source>Biomedicines</source> <volume>11</volume> (<issue>10</issue>), <fpage>2762</fpage>. <pub-id pub-id-type="doi">10.3390/biomedicines11102762</pub-id>
</citation>
</ref>
<ref id="B83">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Mehta</surname>
<given-names>T.</given-names>
</name>
<name>
<surname>Mannem</surname>
<given-names>N.</given-names>
</name>
<name>
<surname>Yarasi</surname>
<given-names>N. K.</given-names>
</name>
<name>
<surname>Bollu</surname>
<given-names>P. C.</given-names>
</name>
</person-group> (<year>2020</year>). <article-title>Biomarkers for ADHD: the present and future directions</article-title>. <source>Curr. Dev. Disord. Rep.</source> <volume>7</volume>, <fpage>85</fpage>&#x2013;<lpage>92</lpage>. <pub-id pub-id-type="doi">10.1007/s40474-020-00196-9</pub-id>
</citation>
</ref>
<ref id="B84">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Mijailovic</surname>
<given-names>N. R.</given-names>
</name>
<name>
<surname>Vesic</surname>
<given-names>K.</given-names>
</name>
<name>
<surname>Arsenijevic</surname>
<given-names>D.</given-names>
</name>
<name>
<surname>Milojevic-Rakic</surname>
<given-names>M.</given-names>
</name>
<name>
<surname>Borovcanin</surname>
<given-names>M. M.</given-names>
</name>
</person-group> (<year>2022</year>). <article-title>Galectin-3 involvement in cognitive processes for new therapeutic considerations</article-title>. <source>Front. Cell Neurosci.</source> <volume>16</volume>, <fpage>923811</fpage>. <pub-id pub-id-type="doi">10.3389/fncel.2022.923811</pub-id>
</citation>
</ref>
<ref id="B85">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Mill</surname>
<given-names>J.</given-names>
</name>
<name>
<surname>Petronis</surname>
<given-names>A.</given-names>
</name>
</person-group> (<year>2008</year>). <article-title>Pre&#x2010;and peri&#x2010;natal environmental risks for attention&#x2010;deficit hyperactivity disorder (ADHD): the potential role of epigenetic processes in mediating susceptibility</article-title>. <source>J. child Psychol. Psychiatry</source> <volume>49</volume> (<issue>10</issue>), <fpage>1020</fpage>&#x2013;<lpage>1030</lpage>. <pub-id pub-id-type="doi">10.1111/j.1469-7610.2008.01909.x</pub-id>
</citation>
</ref>
<ref id="B86">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Mirkovic</surname>
<given-names>B.</given-names>
</name>
<name>
<surname>Chagraoui</surname>
<given-names>A.</given-names>
</name>
<name>
<surname>Gerardin</surname>
<given-names>P.</given-names>
</name>
<name>
<surname>Cohen</surname>
<given-names>D.</given-names>
</name>
</person-group> (<year>2020</year>). <article-title>Epigenetics and attention-deficit/hyperactivity disorder: new perspectives?</article-title> <source>Front. Psychiatry</source> <volume>11</volume>, <fpage>579</fpage>. <pub-id pub-id-type="doi">10.3389/fpsyt.2020.00579</pub-id>
</citation>
</ref>
<ref id="B87">
<citation citation-type="book">
<person-group person-group-type="author">
<name>
<surname>Morimoto</surname>
<given-names>Y.</given-names>
</name>
<name>
<surname>Yamamoto</surname>
<given-names>N.</given-names>
</name>
<name>
<surname>Kanegae</surname>
<given-names>S.</given-names>
</name>
<name>
<surname>Matsuzaka</surname>
<given-names>R.</given-names>
</name>
<name>
<surname>Ozawa</surname>
<given-names>H.</given-names>
</name>
<name>
<surname>Imamura</surname>
<given-names>A.</given-names>
</name>
</person-group> (<year>2021</year>). &#x201c;<article-title>Genetic overlap among autism spectrum disorders and other neuropsychiatric disorders</article-title>,&#x201d; in <source>Autism spectrum disorders</source>. Editor <person-group person-group-type="editor">
<name>
<surname>Grabrucker</surname>
<given-names>A. M.</given-names>
</name>
</person-group> (<publisher-loc>Brisbane, QLD</publisher-loc>: <publisher-name>Exon Publications</publisher-name>).</citation>
</ref>
<ref id="B88">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Muller</surname>
<given-names>U. C.</given-names>
</name>
<name>
<surname>Asherson</surname>
<given-names>P.</given-names>
</name>
<name>
<surname>Banaschewski</surname>
<given-names>T.</given-names>
</name>
<name>
<surname>Buitelaar</surname>
<given-names>J. K.</given-names>
</name>
<name>
<surname>Ebstein</surname>
<given-names>R. P.</given-names>
</name>
<name>
<surname>Eisenberg</surname>
<given-names>J.</given-names>
</name>
<etal/>
</person-group> (<year>2011</year>). <article-title>The impact of study design and diagnostic approach in a large multi-centre ADHD study. Part 1: ADHD symptom patterns</article-title>. <source>BMC Psychiatry</source> <volume>11</volume>, <fpage>54</fpage>. <pub-id pub-id-type="doi">10.1186/1471-244X-11-54</pub-id>
</citation>
</ref>
<ref id="B89">
<citation citation-type="book">
<person-group person-group-type="author">
<name>
<surname>Nigg</surname>
<given-names>J. T.</given-names>
</name>
</person-group> (<year>2018</year>). &#x201c;<article-title>Future directions in ADHD etiology research</article-title>,&#x201d; in <source>Future work in clinical child and adolescent psychology</source> (<publisher-name>Routledge</publisher-name>), <fpage>290</fpage>&#x2013;<lpage>299</lpage>.</citation>
</ref>
<ref id="B90">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Ogdie</surname>
<given-names>M. N.</given-names>
</name>
<name>
<surname>Bakker</surname>
<given-names>S. C.</given-names>
</name>
<name>
<surname>Fisher</surname>
<given-names>S. E.</given-names>
</name>
<name>
<surname>Francks</surname>
<given-names>C.</given-names>
</name>
<name>
<surname>Yang</surname>
<given-names>M. H.</given-names>
</name>
<name>
<surname>Cantor</surname>
<given-names>R. M.</given-names>
</name>
<etal/>
</person-group> (<year>2006</year>). <article-title>Pooled genome-wide linkage data on 424 ADHD ASPs suggests genetic heterogeneity and a common risk locus at 5p13</article-title>. <source>Mol. Psychiatry</source> <volume>11</volume> (<issue>1</issue>), <fpage>5</fpage>&#x2013;<lpage>8</lpage>. <pub-id pub-id-type="doi">10.1038/sj.mp.4001760</pub-id>
</citation>
</ref>
<ref id="B91">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Omran</surname>
<given-names>A. R.</given-names>
</name>
</person-group> (<year>2005</year>). <article-title>The epidemiologic transition: a theory of the epidemiology of population change. 1971</article-title>. <source>Milbank Q.</source> <volume>83</volume> (<issue>4</issue>), <fpage>731</fpage>&#x2013;<lpage>757</lpage>. <pub-id pub-id-type="doi">10.1111/j.1468-0009.2005.00398.x</pub-id>
</citation>
</ref>
<ref id="B92">
<citation citation-type="book">
<person-group person-group-type="author">
<name>
<surname>Organization</surname>
<given-names>W. H.</given-names>
</name>
</person-group> (<year>2004</year>). <source>International statistical classification of diseases and related health problems: alphabetical index. volume 3</source>. <publisher-loc>Switzerland</publisher-loc>: <publisher-name>World Health Organization</publisher-name>.</citation>
</ref>
<ref id="B93">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Polanczyk</surname>
<given-names>G. V.</given-names>
</name>
<name>
<surname>Salum</surname>
<given-names>G. A.</given-names>
</name>
<name>
<surname>Sugaya</surname>
<given-names>L. S.</given-names>
</name>
<name>
<surname>Caye</surname>
<given-names>A.</given-names>
</name>
<name>
<surname>Rohde</surname>
<given-names>L. A.</given-names>
</name>
</person-group> (<year>2015</year>). <article-title>Annual research review: a meta-analysis of the worldwide prevalence of mental disorders in children and adolescents</article-title>. <source>J. Child. Psychol. Psychiatry</source> <volume>56</volume> (<issue>3</issue>), <fpage>345</fpage>&#x2013;<lpage>365</lpage>. <pub-id pub-id-type="doi">10.1111/jcpp.12381</pub-id>
</citation>
</ref>
<ref id="B94">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Polanczyk</surname>
<given-names>G. V.</given-names>
</name>
<name>
<surname>Willcutt</surname>
<given-names>E. G.</given-names>
</name>
<name>
<surname>Salum</surname>
<given-names>G. A.</given-names>
</name>
<name>
<surname>Kieling</surname>
<given-names>C.</given-names>
</name>
<name>
<surname>Rohde</surname>
<given-names>L. A.</given-names>
</name>
</person-group> (<year>2014</year>). <article-title>ADHD prevalence estimates across three decades: an updated systematic review and meta-regression analysis</article-title>. <source>Int. J. Epidemiol.</source> <volume>43</volume> (<issue>2</issue>), <fpage>434</fpage>&#x2013;<lpage>442</lpage>. <pub-id pub-id-type="doi">10.1093/ije/dyt261</pub-id>
</citation>
</ref>
<ref id="B95">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Qoronfleh</surname>
<given-names>M. W.</given-names>
</name>
<name>
<surname>Essa</surname>
<given-names>M. M.</given-names>
</name>
<name>
<surname>Alharahsheh</surname>
<given-names>S. T.</given-names>
</name>
<name>
<surname>Al-Farsi</surname>
<given-names>Y. M.</given-names>
</name>
<name>
<surname>Al-Adawi</surname>
<given-names>S.</given-names>
</name>
</person-group> (<year>2019</year>). <article-title>Autism in the Gulf States: a regional overview</article-title>. <source>Front. Biosci. (Landmark Ed.)</source> <volume>24</volume> (<issue>2</issue>), <fpage>334</fpage>&#x2013;<lpage>346</lpage>. <pub-id pub-id-type="doi">10.2741/4721</pub-id>
</citation>
</ref>
<ref id="B96">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Regan</surname>
<given-names>S. L.</given-names>
</name>
<name>
<surname>Williams</surname>
<given-names>M. T.</given-names>
</name>
<name>
<surname>Vorhees</surname>
<given-names>C. V.</given-names>
</name>
</person-group> (<year>2022</year>). <article-title>Review of rodent models of attention deficit hyperactivity disorder</article-title>. <source>Neurosci. Biobehav Rev.</source> <volume>132</volume>, <fpage>621</fpage>&#x2013;<lpage>637</lpage>. <pub-id pub-id-type="doi">10.1016/j.neubiorev.2021.11.041</pub-id>
</citation>
</ref>
<ref id="B97">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Rivero</surname>
<given-names>O.</given-names>
</name>
<name>
<surname>Alhama-Riba</surname>
<given-names>J.</given-names>
</name>
<name>
<surname>Ku</surname>
<given-names>H. P.</given-names>
</name>
<name>
<surname>Fischer</surname>
<given-names>M.</given-names>
</name>
<name>
<surname>Ortega</surname>
<given-names>G.</given-names>
</name>
<name>
<surname>Almos</surname>
<given-names>P.</given-names>
</name>
<etal/>
</person-group> (<year>2021</year>). <article-title>Haploinsufficiency of the attention-deficit/hyperactivity disorder risk gene St3gal3 in mice causes alterations in cognition and expression of genes involved in myelination and sialylation</article-title>. <source>Front. Genet.</source> <volume>12</volume>, <fpage>688488</fpage>. <pub-id pub-id-type="doi">10.3389/fgene.2021.688488</pub-id>
</citation>
</ref>
<ref id="B98">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Rivero</surname>
<given-names>O.</given-names>
</name>
<name>
<surname>Selten</surname>
<given-names>M. M.</given-names>
</name>
<name>
<surname>Sich</surname>
<given-names>S.</given-names>
</name>
<name>
<surname>Popp</surname>
<given-names>S.</given-names>
</name>
<name>
<surname>Bacmeister</surname>
<given-names>L.</given-names>
</name>
<name>
<surname>Amendola</surname>
<given-names>E.</given-names>
</name>
<etal/>
</person-group> (<year>2015</year>). <article-title>Cadherin-13, a risk gene for ADHD and comorbid disorders, impacts GABAergic function in hippocampus and cognition</article-title>. <source>Transl. Psychiatry</source> <volume>5</volume> (<issue>10</issue>), <fpage>e655</fpage>. <pub-id pub-id-type="doi">10.1038/tp.2015.152</pub-id>
</citation>
</ref>
<ref id="B99">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Russell</surname>
<given-names>V. A.</given-names>
</name>
</person-group> (<year>2011</year>). <article-title>Overview of animal models of attention deficit hyperactivity disorder (ADHD)</article-title>. <source>Curr. Protoc. Neurosci.</source> <volume>Chapter 9</volume>, <fpage>Unit9 35</fpage>. <pub-id pub-id-type="doi">10.1002/0471142301.ns0935s54</pub-id>
</citation>
</ref>
<ref id="B100">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Sarkis</surname>
<given-names>E.</given-names>
</name>
</person-group> (<year>2014</year>). <article-title>Addressing attention-deficit/hyperactivity disorder in the workplace</article-title>. <source>Postgrad. Med.</source> <volume>126</volume> (<issue>5</issue>), <fpage>25</fpage>&#x2013;<lpage>30</lpage>. <pub-id pub-id-type="doi">10.3810/pgm.2014.09.2797</pub-id>
</citation>
</ref>
<ref id="B101">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Semlali</surname>
<given-names>A.</given-names>
</name>
<name>
<surname>Almutairi</surname>
<given-names>M.</given-names>
</name>
<name>
<surname>Rouabhia</surname>
<given-names>M.</given-names>
</name>
<name>
<surname>Reddy Parine</surname>
<given-names>N.</given-names>
</name>
<name>
<surname>Al Amri</surname>
<given-names>A.</given-names>
</name>
<name>
<surname>N</surname>
<given-names>S. A.-N.</given-names>
</name>
<etal/>
</person-group> (<year>2018b</year>). <article-title>Novel sequence variants in the TLR6 gene associated with advanced breast cancer risk in the Saudi Arabian population</article-title>. <source>PLoS One</source> <volume>13</volume> (<issue>11</issue>), <fpage>e0203376</fpage>. <pub-id pub-id-type="doi">10.1371/journal.pone.0203376</pub-id>
</citation>
</ref>
<ref id="B102">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Semlali</surname>
<given-names>A.</given-names>
</name>
<name>
<surname>Parine</surname>
<given-names>N. R.</given-names>
</name>
<name>
<surname>Al-Numair</surname>
<given-names>N. S.</given-names>
</name>
<name>
<surname>Almutairi</surname>
<given-names>M.</given-names>
</name>
<name>
<surname>Hawsawi</surname>
<given-names>Y. M.</given-names>
</name>
<name>
<surname>Amri</surname>
<given-names>A. A.</given-names>
</name>
<etal/>
</person-group> (<year>2018a</year>). <article-title>Potential role of Toll-like receptor 2 expression and polymorphisms in colon cancer susceptibility in the Saudi Arabian population</article-title>. <source>Onco Targets Ther.</source> <volume>11</volume>, <fpage>8127</fpage>&#x2013;<lpage>8141</lpage>. <pub-id pub-id-type="doi">10.2147/OTT.S168478</pub-id>
</citation>
</ref>
<ref id="B103">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Setyanisa</surname>
<given-names>A. R.</given-names>
</name>
<name>
<surname>Setiawati</surname>
<given-names>Y.</given-names>
</name>
<name>
<surname>Irwanto</surname>
<given-names>I.</given-names>
</name>
<name>
<surname>Fithriyah</surname>
<given-names>I.</given-names>
</name>
<name>
<surname>Prabowo</surname>
<given-names>S. A.</given-names>
</name>
</person-group> (<year>2022</year>). <article-title>Relationship between parenting style and risk of attention deficit hyperactivity disorder in elementary school children</article-title>. <source>Malays J. Med. Sci.</source> <volume>29</volume> (<issue>4</issue>), <fpage>152</fpage>&#x2013;<lpage>159</lpage>. <pub-id pub-id-type="doi">10.21315/mjms2022.29.4.14</pub-id>
</citation>
</ref>
<ref id="B104">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Simsek</surname>
<given-names>M.</given-names>
</name>
<name>
<surname>Al-Sharbati</surname>
<given-names>M.</given-names>
</name>
<name>
<surname>Al-Adawi</surname>
<given-names>S.</given-names>
</name>
<name>
<surname>Ganguly</surname>
<given-names>S. S.</given-names>
</name>
<name>
<surname>Lawatia</surname>
<given-names>K.</given-names>
</name>
</person-group> (<year>2005</year>). <article-title>Association of the risk allele of dopamine transporter gene (DAT1&#x2a;10) in Omani male children with attention-deficit hyperactivity disorder</article-title>. <source>Clin. Biochem.</source> <volume>38</volume> (<issue>8</issue>), <fpage>739</fpage>&#x2013;<lpage>742</lpage>. <pub-id pub-id-type="doi">10.1016/j.clinbiochem.2005.04.016</pub-id>
</citation>
</ref>
<ref id="B105">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Sontag</surname>
<given-names>T. A.</given-names>
</name>
<name>
<surname>Tucha</surname>
<given-names>O.</given-names>
</name>
<name>
<surname>Walitza</surname>
<given-names>S.</given-names>
</name>
<name>
<surname>Lange</surname>
<given-names>K. W.</given-names>
</name>
</person-group> (<year>2010</year>). <article-title>Animal models of attention deficit/hyperactivity disorder (ADHD): a critical review</article-title>. <source>Atten. Defic. Hyperact. Disord.</source> <volume>2</volume> (<issue>1</issue>), <fpage>1</fpage>&#x2013;<lpage>20</lpage>. <pub-id pub-id-type="doi">10.1007/s12402-010-0019-x</pub-id>
</citation>
</ref>
<ref id="B106">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Sonuga-Barke</surname>
<given-names>E. J. S.</given-names>
</name>
<name>
<surname>Becker</surname>
<given-names>S. P.</given-names>
</name>
<name>
<surname>Bolte</surname>
<given-names>S.</given-names>
</name>
<name>
<surname>Castellanos</surname>
<given-names>F. X.</given-names>
</name>
<name>
<surname>Franke</surname>
<given-names>B.</given-names>
</name>
<name>
<surname>Newcorn</surname>
<given-names>J. H.</given-names>
</name>
<etal/>
</person-group> (<year>2023</year>). <article-title>Annual Research Review: perspectives on progress in ADHD science - from characterization to cause</article-title>. <source>J. Child. Psychol. Psychiatry</source> <volume>64</volume> (<issue>4</issue>), <fpage>506</fpage>&#x2013;<lpage>532</lpage>. <pub-id pub-id-type="doi">10.1111/jcpp.13696</pub-id>
</citation>
</ref>
<ref id="B107">
<citation citation-type="confproc">
<person-group person-group-type="author">
<name>
<surname>Spiel</surname>
<given-names>K.</given-names>
</name>
<name>
<surname>Hornecker</surname>
<given-names>E.</given-names>
</name>
<name>
<surname>Williams</surname>
<given-names>R. M.</given-names>
</name>
<name>
<surname>Good</surname>
<given-names>J.</given-names>
</name>
</person-group> (<year>2022</year>). &#x201c;<article-title>ADHD and technology research&#x2013;investigated by neurodivergent readers</article-title>,&#x201d; in <conf-name>Proceedings of the 2022 CHI conference on human factors in computing systems</conf-name>. <fpage>1</fpage>&#x2013;<lpage>21</lpage>.</citation>
</ref>
<ref id="B108">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Sudre</surname>
<given-names>G.</given-names>
</name>
<name>
<surname>Choudhuri</surname>
<given-names>S.</given-names>
</name>
<name>
<surname>Szekely</surname>
<given-names>E.</given-names>
</name>
<name>
<surname>Bonner</surname>
<given-names>T.</given-names>
</name>
<name>
<surname>Goduni</surname>
<given-names>E.</given-names>
</name>
<name>
<surname>Sharp</surname>
<given-names>W.</given-names>
</name>
<etal/>
</person-group> (<year>2017</year>). <article-title>Estimating the heritability of structural and functional brain connectivity in families affected by attention-deficit/hyperactivity disorder</article-title>. <source>JAMA Psychiatry</source> <volume>74</volume> (<issue>1</issue>), <fpage>76</fpage>&#x2013;<lpage>84</lpage>. <pub-id pub-id-type="doi">10.1001/jamapsychiatry.2016.3072</pub-id>
</citation>
</ref>
<ref id="B109">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Thapar</surname>
<given-names>A.</given-names>
</name>
</person-group> (<year>2018</year>). <article-title>Discoveries on the genetics of ADHD in the 21st century: new findings and their implications</article-title>. <source>Am. J. Psychiatry</source> <volume>175</volume> (<issue>10</issue>), <fpage>943</fpage>&#x2013;<lpage>950</lpage>. <pub-id pub-id-type="doi">10.1176/appi.ajp.2018.18040383</pub-id>
</citation>
</ref>
<ref id="B110">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Thomas</surname>
<given-names>R.</given-names>
</name>
<name>
<surname>Sanders</surname>
<given-names>S.</given-names>
</name>
<name>
<surname>Doust</surname>
<given-names>J.</given-names>
</name>
<name>
<surname>Beller</surname>
<given-names>E.</given-names>
</name>
<name>
<surname>Glasziou</surname>
<given-names>P.</given-names>
</name>
</person-group> (<year>2015</year>). <article-title>Prevalence of attention-deficit/hyperactivity disorder: a systematic review and meta-analysis</article-title>. <source>Pediatrics</source> <volume>135</volume> (<issue>4</issue>), <fpage>e994</fpage>&#x2013;<lpage>e1001</lpage>. <pub-id pub-id-type="doi">10.1542/peds.2014-3482</pub-id>
</citation>
</ref>
<ref id="B111">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Thome</surname>
<given-names>J.</given-names>
</name>
<name>
<surname>Jacobs</surname>
<given-names>K. A.</given-names>
</name>
</person-group> (<year>2004</year>). <article-title>Attention deficit hyperactivity disorder (ADHD) in a 19th century children&#x27;s book</article-title>. <source>Eur. Psychiatry</source> <volume>19</volume> (<issue>5</issue>), <fpage>303</fpage>&#x2013;<lpage>306</lpage>. <pub-id pub-id-type="doi">10.1016/j.eurpsy.2004.05.004</pub-id>
</citation>
</ref>
<ref id="B112">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Thygesen</surname>
<given-names>J. H.</given-names>
</name>
<name>
<surname>Presman</surname>
<given-names>A.</given-names>
</name>
<name>
<surname>Harju-Seppanen</surname>
<given-names>J.</given-names>
</name>
<name>
<surname>Irizar</surname>
<given-names>H.</given-names>
</name>
<name>
<surname>Jones</surname>
<given-names>R.</given-names>
</name>
<name>
<surname>Kuchenbaecker</surname>
<given-names>K.</given-names>
</name>
<etal/>
</person-group> (<year>2021</year>). <article-title>Genetic copy number variants, cognition and psychosis: a meta-analysis and a family study</article-title>. <source>Mol. Psychiatry</source> <volume>26</volume> (<issue>9</issue>), <fpage>5307</fpage>&#x2013;<lpage>5319</lpage>. <pub-id pub-id-type="doi">10.1038/s41380-020-0820-7</pub-id>
</citation>
</ref>
<ref id="B113">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>van Hulst</surname>
<given-names>B. M.</given-names>
</name>
<name>
<surname>de Zeeuw</surname>
<given-names>P.</given-names>
</name>
<name>
<surname>Durston</surname>
<given-names>S.</given-names>
</name>
</person-group> (<year>2015</year>). <article-title>Distinct neuropsychological profiles within ADHD: a latent class analysis of cognitive control, reward sensitivity and timing</article-title>. <source>Psychol. Med.</source> <volume>45</volume> (<issue>4</issue>), <fpage>735</fpage>&#x2013;<lpage>745</lpage>. <pub-id pub-id-type="doi">10.1017/S0033291714001792</pub-id>
</citation>
</ref>
<ref id="B114">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Viggiano</surname>
<given-names>D.</given-names>
</name>
<name>
<surname>Vallone</surname>
<given-names>D.</given-names>
</name>
<name>
<surname>Sadile</surname>
<given-names>A.</given-names>
</name>
</person-group> (<year>2004</year>). <article-title>Dysfunctions in dopamine systems and ADHD: evidence from animals and modeling</article-title>. <source>Neural Plast.</source> <volume>11</volume> (<issue>1-2</issue>), <fpage>97</fpage>&#x2013;<lpage>114</lpage>. <pub-id pub-id-type="doi">10.1155/NP.2004.97</pub-id>
</citation>
</ref>
<ref id="B115">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Villani</surname>
<given-names>V.</given-names>
</name>
<name>
<surname>Ludmer</surname>
<given-names>J.</given-names>
</name>
<name>
<surname>Gonzalez</surname>
<given-names>A.</given-names>
</name>
<name>
<surname>Levitan</surname>
<given-names>R.</given-names>
</name>
<name>
<surname>Kennedy</surname>
<given-names>J.</given-names>
</name>
<name>
<surname>Masellis</surname>
<given-names>M.</given-names>
</name>
<etal/>
</person-group> (<year>2018</year>). <article-title>Dopamine receptor D2 (DRD2), dopamine transporter solute carrier family C6, member 4 (SLC6A3), and catechol-O-methyltransferase (COMT) genes as moderators of the relation between maternal history of maltreatment and infant emotion regulation</article-title>. <source>Dev. Psychopathol.</source> <volume>30</volume> (<issue>2</issue>), <fpage>581</fpage>&#x2013;<lpage>592</lpage>. <pub-id pub-id-type="doi">10.1017/S0954579417001122</pub-id>
</citation>
</ref>
<ref id="B116">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Wahlstedt</surname>
<given-names>C.</given-names>
</name>
<name>
<surname>Thorell</surname>
<given-names>L. B.</given-names>
</name>
<name>
<surname>Bohlin</surname>
<given-names>G.</given-names>
</name>
</person-group> (<year>2009</year>). <article-title>Heterogeneity in ADHD: neuropsychological pathways, comorbidity and symptom domains</article-title>. <source>J. Abnorm Child. Psychol.</source> <volume>37</volume> (<issue>4</issue>), <fpage>551</fpage>&#x2013;<lpage>564</lpage>. <pub-id pub-id-type="doi">10.1007/s10802-008-9286-9</pub-id>
</citation>
</ref>
<ref id="B117">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Walton</surname>
<given-names>E.</given-names>
</name>
<name>
<surname>Pingault</surname>
<given-names>J. B.</given-names>
</name>
<name>
<surname>Cecil</surname>
<given-names>C. A.</given-names>
</name>
<name>
<surname>Gaunt</surname>
<given-names>T. R.</given-names>
</name>
<name>
<surname>Relton</surname>
<given-names>C. L.</given-names>
</name>
<name>
<surname>Mill</surname>
<given-names>J.</given-names>
</name>
<etal/>
</person-group> (<year>2017</year>). <article-title>Epigenetic profiling of ADHD symptoms trajectories: a prospective, methylome-wide study</article-title>. <source>Mol. Psychiatry</source> <volume>22</volume> (<issue>2</issue>), <fpage>250</fpage>&#x2013;<lpage>256</lpage>. <pub-id pub-id-type="doi">10.1038/mp.2016.85</pub-id>
</citation>
</ref>
<ref id="B118">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Wender</surname>
<given-names>P. H.</given-names>
</name>
<name>
<surname>Wolf</surname>
<given-names>L. E.</given-names>
</name>
<name>
<surname>Wasserstein</surname>
<given-names>J.</given-names>
</name>
</person-group> (<year>2001</year>). <article-title>Adults with ADHD. An overview</article-title>. <source>Ann. N. Y. Acad. Sci.</source> <volume>931</volume>, <fpage>1</fpage>&#x2013;<lpage>16</lpage>. <pub-id pub-id-type="doi">10.1111/j.1749-6632.2001.tb05770.x</pub-id>
</citation>
</ref>
<ref id="B119">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>White</surname>
<given-names>H. A.</given-names>
</name>
<name>
<surname>Shah</surname>
<given-names>P.</given-names>
</name>
</person-group> (<year>2011</year>). <article-title>Creative style and achievement in adults with attention-deficit/hyperactivity disorder</article-title>. <source>Personality Individ. Differ.</source> <volume>50</volume> (<issue>5</issue>), <fpage>673</fpage>&#x2013;<lpage>677</lpage>. <pub-id pub-id-type="doi">10.1016/j.paid.2010.12.015</pub-id>
</citation>
</ref>
<ref id="B120">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Wiklund</surname>
<given-names>J.</given-names>
</name>
<name>
<surname>Yu</surname>
<given-names>W.</given-names>
</name>
<name>
<surname>Tucker</surname>
<given-names>R.</given-names>
</name>
<name>
<surname>Marino</surname>
<given-names>L. D.</given-names>
</name>
</person-group> (<year>2017</year>). <article-title>ADHD, impulsivity and entrepreneurship</article-title>. <source>J. Bus. Ventur.</source> <volume>32</volume> (<issue>6</issue>), <fpage>627</fpage>&#x2013;<lpage>656</lpage>. <pub-id pub-id-type="doi">10.1016/j.jbusvent.2017.07.002</pub-id>
</citation>
</ref>
<ref id="B121">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Wilmot</surname>
<given-names>B.</given-names>
</name>
<name>
<surname>Fry</surname>
<given-names>R.</given-names>
</name>
<name>
<surname>Smeester</surname>
<given-names>L.</given-names>
</name>
<name>
<surname>Musser</surname>
<given-names>E. D.</given-names>
</name>
<name>
<surname>Mill</surname>
<given-names>J.</given-names>
</name>
<name>
<surname>Nigg</surname>
<given-names>J. T.</given-names>
</name>
</person-group> (<year>2016</year>). <article-title>Methylomic analysis of salivary DNA in childhood ADHD identifies altered DNA methylation in VIPR2</article-title>. <source>J. Child. Psychol. Psychiatry</source> <volume>57</volume> (<issue>2</issue>), <fpage>152</fpage>&#x2013;<lpage>160</lpage>. <pub-id pub-id-type="doi">10.1111/jcpp.12457</pub-id>
</citation>
</ref>
<ref id="B122">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Wolraich</surname>
<given-names>M. L.</given-names>
</name>
<name>
<surname>Chan</surname>
<given-names>E.</given-names>
</name>
<name>
<surname>Froehlich</surname>
<given-names>T.</given-names>
</name>
<name>
<surname>Lynch</surname>
<given-names>R. L.</given-names>
</name>
<name>
<surname>Bax</surname>
<given-names>A.</given-names>
</name>
<name>
<surname>Redwine</surname>
<given-names>S. T.</given-names>
</name>
<etal/>
</person-group> (<year>2019</year>). <article-title>ADHD diagnosis and treatment guidelines: a historical perspective</article-title>. <source>Pediatrics</source> <volume>144</volume> (<issue>4</issue>), <fpage>e20191682</fpage>. <pub-id pub-id-type="doi">10.1542/peds.2019-1682</pub-id>
</citation>
</ref>
<ref id="B123">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Yadav</surname>
<given-names>S. K.</given-names>
</name>
<name>
<surname>Bhat</surname>
<given-names>A. A.</given-names>
</name>
<name>
<surname>Hashem</surname>
<given-names>S.</given-names>
</name>
<name>
<surname>Nisar</surname>
<given-names>S.</given-names>
</name>
<name>
<surname>Kamal</surname>
<given-names>M.</given-names>
</name>
<name>
<surname>Syed</surname>
<given-names>N.</given-names>
</name>
<etal/>
</person-group> (<year>2021</year>). <article-title>Genetic variations influence brain changes in patients with attention-deficit hyperactivity disorder</article-title>. <source>Transl. Psychiatry</source> <volume>11</volume> (<issue>1</issue>), <fpage>349</fpage>. <pub-id pub-id-type="doi">10.1038/s41398-021-01473-w</pub-id>
</citation>
</ref>
<ref id="B124">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Zayats</surname>
<given-names>T.</given-names>
</name>
<name>
<surname>Neale</surname>
<given-names>B. M.</given-names>
</name>
</person-group> (<year>2019</year>). <article-title>Recent advances in understanding of attention deficit hyperactivity disorder (ADHD): how genetics are shaping our conceptualization of this disorder</article-title>. <source>F1000Res</source> <volume>8</volume>, <fpage>F1000 Faculty Rev-2060</fpage>. <pub-id pub-id-type="doi">10.12688/f1000research.18959.2</pub-id>
</citation>
</ref>
<ref id="B125">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Zhang-James</surname>
<given-names>Y.</given-names>
</name>
<name>
<surname>DasBanerjee</surname>
<given-names>T.</given-names>
</name>
<name>
<surname>Sagvolden</surname>
<given-names>T.</given-names>
</name>
<name>
<surname>Middleton</surname>
<given-names>F. A.</given-names>
</name>
<name>
<surname>Faraone</surname>
<given-names>S. V.</given-names>
</name>
</person-group> (<year>2011</year>). <article-title>SLC9A9 mutations, gene expression, and protein-protein interactions in rat models of attention-deficit/hyperactivity disorder</article-title>. <source>Am. J. Med. Genet. B Neuropsychiatr. Genet.</source> <volume>156B</volume> (<issue>7</issue>), <fpage>835</fpage>&#x2013;<lpage>843</lpage>. <pub-id pub-id-type="doi">10.1002/ajmg.b.31229</pub-id>
</citation>
</ref>
<ref id="B126">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Zhang-James</surname>
<given-names>Y.</given-names>
</name>
<name>
<surname>Middleton</surname>
<given-names>F. A.</given-names>
</name>
<name>
<surname>Sagvolden</surname>
<given-names>T.</given-names>
</name>
<name>
<surname>Faraone</surname>
<given-names>S. V.</given-names>
</name>
</person-group> (<year>2012</year>). <article-title>Differential expression of SLC9A9 and interacting molecules in the hippocampus of rat models for attention deficit/hyperactivity disorder</article-title>. <source>Dev. Neurosci.</source> <volume>34</volume> (<issue>2-3</issue>), <fpage>218</fpage>&#x2013;<lpage>227</lpage>. <pub-id pub-id-type="doi">10.1159/000338813</pub-id>
</citation>
</ref>
<ref id="B127">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Zheng</surname>
<given-names>Y.</given-names>
</name>
<name>
<surname>Pingault</surname>
<given-names>J. B.</given-names>
</name>
<name>
<surname>Unger</surname>
<given-names>J. B.</given-names>
</name>
<name>
<surname>Rijsdijk</surname>
<given-names>F.</given-names>
</name>
</person-group> (<year>2020</year>). <article-title>Genetic and environmental influences on attention-deficit/hyperactivity disorder symptoms in Chinese adolescents: a longitudinal twin study</article-title>. <source>Eur. Child. Adolesc. Psychiatry</source> <volume>29</volume> (<issue>2</issue>), <fpage>205</fpage>&#x2013;<lpage>216</lpage>. <pub-id pub-id-type="doi">10.1007/s00787-019-01346-0</pub-id>
</citation>
</ref>
</ref-list>
</back>
</article>