The purpose of this study is to identify genes and proteins responsible for nerve and muscle disorders by studying genetic material from individuals with neuromuscular disease, as well as their family members. We are interested in recruiting many types of neuromuscular disease including; Duchenne muscular dystrophy (DMD), Becker muscular dystrophy (BMD), and limb-girdle muscle dystrophy (LGMD). There are still many patients diagnosed with muscular dystrophy but have no causative gene implicated in their disease. We feel that these patients may have new genetic changes in genes coding for important muscle proteins that we have yet to identify. Using molecular genetics to unravel the biochemical basis of these neuromuscular disorders should lead to more accurate diagnosis of these disorders and should lead to potential therapies.