What are the salient features of the Duchenne muscular dystrophy (DMD) gene?
The gene is large (2.3 Mb), located in the short arm of the X chromosome, and codes for a structural protein called dystrophin.
It is by far the largest gene characterized to date, consisting of 2.3 million base pairs and occupying approximately 1% of the human X chromosome.
Dystrophin is a protein located in the subsarcolemmal region of the muscle fiber, which functions in linking the extracellular matrix to the sarcomere.
Mutations that result in complete absence of dystrophin result in the severe DMD, whereas mutations found with the milder BMD lead to variable amounts of partially functioning dystrophin.
