Do you have Becker muscular dystrophy? Learn about joining the Canadian Neuromuscular Disease Registry.
Becker muscular dystrophy (BMD) is an inherited degenerative muscle disorder that occurs almost exclusively in males. BMD is similar to DMD — both are caused by a mutation in the dystrophin gene on the X chromosome. This protein is an important building block that helps give muscles structure and strength.
Both DMD and BMD primarily affect skeletal muscles, which are used for movement, and heart (cardiac) muscle. However, BMD is less common — 1 in 35,000 males worldwide — and has a later onset and slower progression than DMD.
Symptoms typically appear between the ages of 5 and 15 and include difficulty with:
Important: Due to heart muscle weakening, people with BMD have a high risk of developing heart disease (cardiomyopathy). Heart health should be monitored closely. Cardiovascular Health Supervision for Individuals Affected by DMD and DMD (Pediatrics, 2005)
New therapeutic trials for DMD demand accurate diagnosis of the disorder, especially where the therapy is targeted towards specific mutations. These guidelines aim to help diagnos- tic laboratories attain that accuracy by describing the minimum standards for acceptable molecular diagnostic testing of DMD. For the different types of clinical referral received by a molecular diagnostic laboratory, the guidelines recommend the appropriate tests to be carried out, interpretation of the results and how those results should be reported.