P681: Molecular diagnosis of DMD-related dystrophinopathies in patients with non-representative phenotypes by using a broad neuromuscular next generation sequencing (NGS) panel

X-linked DMD-related dystrophinopathies include Duchenne muscular dystrophy (DMD), Becker muscular dystrophy (BMD), and DMD-associated dilated cardiomyopathy (DCM). The clinical manifestations of dystrophinopathies can vary from asymptomatic, increased creatine phosphokinase (CK) in serum to severe, progressive DMD/BMD, or dilated cardiomyopathy. As deletions of DMD exons account for approximately 60%-70% of pathogenic variants in individuals with DMD/BMD, deletion/duplication analysis of the DMD gene has been the initial testing strategy, followed by sequence analysis if no copy number variant (CNV) is identified.