About this Research Topic
Somatic mosaicism is probably the most enigmatic type of genomic variations. Since all cells of the human organism (>1014) are unlikely to share identical genomes, it is suggested that all humans are genetically mosaic. Accordingly, it is generally difficult to define the presence and consequences of somatic mosaicism in an individual. Despite being a focus of attention for more than a half of a century, studies of mosaicism remain an important part of current genetic and genomic research. With the introduction of whole-genome single-cell technologies, somatic mosaicism has been re-considered in the light of its contribution to human morbidity. Thus, the contribution of somatic (chromosomal and single-gene) mosaicism to human interindividual diversity in health and disease has been found to be more important than previously recognized. Currently, a need for a generalized view on the role of chromosomal, subchromosomal and single-gene mosaicism appears to exist.
Numerous studies highlighting causes and consequences of genetic mosaicism have formed a strong theoretical basis for investigations of intercellular genome variations. Still, intrinsic mechanisms for somatic mosaicism remain elusive. Somatic genome variations have been reported to be involved in pathogenesis of a wide spectrum of diseases. Genomic instability is a hallmark of cancer and a number of non-cancerous diseases (i.e. neurodegenerative and neurodevelopmental disorders). Chromosomal mosaicism has been studied for more than 50 years. However, the true role of somatic chromosomal mosaicism in the etiology of human diseases is far from being completely established. Interestingly, somatic mosaicism is an important mechanism for brain disorders. Since a neuron is able to form more than a thousand connections to other neurons, somatic mosaicism affecting a proportion of neuronal cells in the brain is likely to possess a more appreciable impact on the functioning. Therefore, it is not surprising that brain disorders have become a major focus of neurogenomic research targeting at uncovering variations of cellular genomes in the human brain. Likewise, diseases associated with tissue-specific mosaicism have been repeatedly addressed in the light of studying somatic genome variations. Finally, somatic mosaicism is suggested to be a mechanism for human aging. The accumulation of somatic mutations in late ontogeny is likely to mediate cellular senescence and tissue aging. The aim of this Research Topic is to collect high-quality contributions dedicated to the multifaceted nature of somatic mosaicism in humans and its role in the etiology of human disease.
The Research Topic covers all areas of genetic research focused on somatic genetic mosaicism in its widest sense, including but not limited to:
I) Causes and consequences of somatic mosaicism;
II) Genomic instability in cancer and non-cancerous diseases;
III) Chromosomal mosaicism;
IV) Somatic mosaicism and brain disorders;
V) Single-gene mosaicism and disease;
VI) Aging and somatic mosaicism;
VII) Single-cell approaches to somatic mosaicism.
Keywords: Somatic mosaicism, Genomic variaitons, Chromosomes, Genome instability, Disease mechanisms
Important Note: All contributions to this Research Topic must be within the scope of the section and journal to which they are submitted, as defined in their mission statements. Frontiers reserves the right to guide an out-of-scope manuscript to a more suitable section or journal at any stage of peer review.