Muscular dystrophies are a heterogeneous group of inherited disorders characterized by progressive muscle wasting and weakness. Majority of genes and their protein products responsible for the dystrophies have been identified in recent years. Using molecular studies, now it is possible to establish a precise diagnosis, provide prognosis, detect preclinical cases, identify carriers, and offer prenatal diagnostic testing. Molecular genetic approaches also seem to offer the best prospect for developing effective treatments in the future.