The group includes:
Becker muscular dystrophy
congenital muscular dystrophy (CMD)
Duchenne muscular dystrophy and manifesting carrier of Duchenne
Emery-Dreifuss muscular dystrophy
facioscapulohumeral muscular dystrophy
limb girdle muscular dystrophy
oculopharyngeal muscular dystrophy (OPMD).
Different forms of muscular dystrophy can vary hugely in severity. Symptoms can be seen at birth or in the first months of life – for example, in congenital muscular dystrophy. Or they can be very mild and first noticed between the ages of 40 and 50 – for example, in oculopharyngeal muscular dystrophy.
We now know the underlying genetic defect for most of the muscular dystrophies. It generally involves a defect in a protein that plays a vital role in muscle cell function or repair. However, for a small number of people, the genetic cause has yet to be found.
As research advances, it becomes increasingly complex to categorise muscular dystrophies. For example, there are now 19 different genes known to cause limb girdle muscular dystrophy.
About 8,000 to 10,000 people in the UK have a form of muscular dystrophy.