DMD and muscular dystrophy: Dystrophinopathies are caused by a variety of types of mutations in the dystrophin gene (exonic deletions and duplications, a range of smaller mutations within exons, as well as rare deletions to non-coding regions).  Molecular genetic testing for Duchenne/Becker has experienced vast improvements in the past decade, and is currently a recommended aspect of confirming a diagnosis of muscular dystrophy ([1]).  In the registry questionnaire, participants may enter the type and location of the causative mutation.