AUTHOR=Li Qingchuan , Sun Zhihong , Qiu Zeping , Chen Yanjia , Jin Wei 

TITLE=A novel LAMP2 initiation codon mutation causes Danon Disease: a case report

JOURNAL=Frontiers in Cardiovascular Medicine

VOLUME=Volume 12 - 2025

YEAR=2025

URL=https://www.frontiersin.org/journals/cardiovascular-medicine/articles/10.3389/fcvm.2025.1699732

DOI=10.3389/fcvm.2025.1699732

ISSN=2297-055X

ABSTRACT=Danon Disease (DD) is a rare X-linked inherited disorder caused by severe deficiency of lysosome-associated membrane protein-2 (LAMP-2), encoded by the LAMP2 gene. Characteristic clinical features include a triad of cardiomyopathy, skeletal myopathy and cognitive impairment in males. Females usually exhibit milder, cardiac-predominant manifestations later in life. In this case, we report a 30-year-old woman with a novel suspected pathogenic LAMP2 mutation (c.1A > T, initiation codon mutation). She developed Wolff-Parkinson-White (WPW) syndrome in her twenties, acute heart failure post cesarean section at age 29, and persistent left ventricular hypertrophy. Positive result of Technetium-99 m pyrophosphate (99mTc-PYP) scintigraphy strongly indicated transthyretin amyloid cardiomyopathy (ATTR-CM). However, whole-exome sequencing (WES) identified the novel A to T transition in initiation codon (c.1A > T) of LAMP2 gene, establishing the diagnosis of DD and revealing the false-positive result of PYP scintigraphy in DD.