Duchenne muscular dystrophy is the most common and most severe type of muscular dystrophy, and is caused by a faulty gene that prevents the production of a protein called dystrophin. It usually affects boys (about one in 3,500), but it can occasionally affect girls as well. Duchenne muscular dystrophy causes progressive weakness in the muscles of the legs, leading to mobility (movement) problems in young children. Most children with the condition will require a wheelchair by the age of 11.
