Related Experiment Video
Updated: Mar 24, 2026

In Vivo Functional Study of Disease-associated Rare Human Variants Using Drosophila
Published on: August 20, 2019
Somatic mosaicism due to a reversion variant causing hemi-atrophy: a novel variant of dystrophinopathy
Jaya Punetha1,2, Simin Mansoor3, Tulio E Bertorini3
1Department of Integrative Systems Biology, The George Washington University School of Medicine, Washington, DC, USA.
Abstract:
We describe a case of hemi-atrophy in a young adult male, with a positive family history of three maternal uncles with Duchenne muscular dystrophy (DMD). The patient showed progressive weakness localized to the left side, an abnormal electromyography, and creatine kinase levels >3000 IU/l. Muscle biopsy showed both dystrophin-positive and -negative myofibers. An out-of-frame duplication variant in DMD, that is, c.(93+1_94-1)_(649+1_650-1)dup(p.?) resulting in duplication of exons 3-7 was inherited, but the muscle biopsy showed dystrophin mRNA with and without the duplication. Dystrophin quantification using mass spectrometry showed 25% normal dystrophin protein levels in the muscle biopsy from the stronger right side. Sex chromosome aneuploidy was ruled out. We conclude that the patient inherited the duplication variant, but early in development an inner cell mass underwent a somatic recombination event removing the duplication and restoring dystrophin expression. To our knowledge, this is the first report of a reversion leading to somatic mosaicism in DMD.
More Related Videos
Related Concept Videos
Satellite Stem Cells and Muscular Dystrophy
Cardiomyopathy III: Hypertrophic Cardiomyopathy
Incomplete Dominance
Nondisjunction
Nondisjunction
Meiosis I

