Duchenne muscular dystrophy (DMD) is a serious condition of genetic origin that is passed down in the X-linked manner and that mainly afflicts boys. It is the result of a steady muscle tissue degeneration caused by mutations in the dystrophin gene on the X chromosome. Without dystrophin, a protein essential for the structure of muscle fibers, muscle cells become unstable and die. Signs of the condition usually appear in early childhood, and any number of developmental delays in movement may be noted along with the following: frequent falling, calf muscles that are enlarged, life-threatening problems involving the heart and lungs average around 20 years. Standard treatments delay muscle decline and enhance mobility, though they carry a range of effects.