{Reference Type}: Case Reports
{Title}: An early onset benign myopathy with glycogen storage caused by a de novo 1.4 Mb-deletion of chromosome 14.
{Author}: Severa G;Pennisi A;Barnerias C;Fiorillo C;Scala M;Taglietti V;Cojocaru AI;Jouni D;Tosca L;Tachdjian G;Desguerre I;Authier FJ;Carlier RY;Metay C;Verebi C;Malfatti E;
{Journal}: Neuromuscul Disord
{Volume}: 33
{Issue}: 10
{Year}: 2023 Oct 25
{Factor}: 3.538
{DOI}: 10.1016/j.nmd.2023.08.011
{Abstract}: Early onset myopathies are a clinically and histologically heterogeneous monogenic diseases linked to approximately 90 genes. Molecular diagnosis is challenging, especially in patients with a mild phenotype. We describe a 26-year-old man with neonatal hypotonia, motor delay and seizures during infancy, and non-progressive, mild muscular weakness in adulthood. Serum Creatine kinase level was normal. Whole-body muscle MRI showed thin muscles, and brain MRI was unremarkable. A deltoid muscle biopsy showed glycogen storage. WGS revealed a de novo 1.4 Mb-deletion of chromosome 14, confirmed by Array-CGH. This microdeletion causes the loss of ten genes including RALGAPA1, encoding for RalA, a regulator of glucose transporter 4 (GLUT4) expression at the membrane of myofibers. GLUT4 was overexpressed in patient's muscle. Here we highlight the importance to search for chromosomal alterations in the diagnostic workup of early onset myopathies.