Dystrophin gene (DMD OMIM *300377) mutations account for different allelic conditions: Duchenne muscular dystrophy (DMD, OMIM *310200), which is the most common form of muscular dystrophy in childhood, occurring in 1 in 3,500 to 5,000 male births, and Becker muscular dystrophy (BMD, OMIM *300376), a milder form, with an incidence of 1 in 20,000 live male births (Mah, 2016). The gene discussed is DMD; the disease is Duchenne muscular dystrophy.