Dystrophin-associated muscular dystrophies range from the severe Duchenne muscular dystrophy to the milder Becker muscular dystrophy . Mapping and molecular genetic studies indicate that both are the result of mutations in the huge gene that encodes dystrophin, also symbolized DMD. Approximately two-thirds of the mutations in both forms are deletions of one or many exons in the dystrophin gene. Currently there is no clear correlation found between the extent of the deletion and the severity of the disorder.
Confirmation of a clinical diagnosis, Carrier testing in unaffected family members