Duchenne muscular dystrophy (DMD) is an inherited X-linked disorder with an incidence of 1 in 3,500 male births that is due to the absence of dystrophin, a large protein linking the intracellular cytoskeleton to the extracellular matrix.[1] The animal model of DMD, the mdx mouse, is genetically similar to the human deletion.[1]–[3] Although the underlying gene defect is the same in human and the mdx mouse, the clinical picture is quite different. The gene discussed is DMD; the disease is Duchenne muscular dystrophy.