What is duschene muscular dystrophy

DMD is an X-linked recessive disease and is the commonest childhood muscular dystrophy. The basic defect is the absence of dystrophin a protein in skeletal muscle, cardiac muscle and brain. In muscle, this binds the contractile filaments to the sarcoplasmic membrane. Absence of dystrophin renders the sarcolemma susceptible to breaks and tears during muscle contraction and allowing entry of calcium ions into cell leading to cell death. The gene is located at Mp 21 site. The disease presents when the child stands up from squatting. As time passes weakness increase and respiratory muscle weakness leads to death. The selective involvement of muscles spares certain muscles like deltoid and hypertrophy of calf muscle occur with contracture. Brain involvement may result in mild mental retardation. Treatment with steroids and supportive physiotherapy may delay the progression of the disease. Newer modalities of treatment include myoblast transfer therapy and gene therapy which are yet to become completely successful.