Muscular dystrophy is a disease characterized by weakness and deterioration of skeletal muscles. There are over 30 different forms of muscular dystrophy, but the two most common are Duchenne and Becker (Baroncelli) muscular dystrophy. These two forms of the disease are sex-linked and mainly affect males. A male usually inherits a defective X chromosome from his mother and does not receive any other X chromosome to make up for the defective one (males are XY). Affected people have difficulty carrying out daily activities and eventually lose the ability to walk. However, a defective X chromosome inherited from one female can be compensated for by a normal X chromosome inherited from the other parent (females are XX). Females are the typical carriers of the disease which occurs mainly when their children inherit a defective X chromosome. Both forms of muscular dystrophy result from mutations in the DMD gene that result in the inability to produce a functional or sufficient amount of dystrophin, the protein that strengthens and protects muscle fibers. Without effective dystrophin, muscle fibers weaken and die...