DMD and Duchenne muscular dystrophy: Duchenne muscular dystrophy (DMD; OMIM 310200) is a rare, degenerative X-linked neuromuscular disorder that occurs in approximately 1 in 3500 to 5000 live male births with a pooled global prevalence of 4.78 per 100,000 (95% confidence interval [CI] = 1.9–11.8).1, –3 DMD is associated with progressive muscle-wasting caused by mutations in the DMD gene that prevent the production of the functional muscle isoform of dystrophin (Dp427m).4 Thousands of different mutations have been reported in the DMD gene.