How is Duchenne or Becker muscular dystrophy diagnosed?

Duchenne and Becker muscular dystrophy are names for the same disorder caused by genetic mutations in the DMD gene. It is diagnosed by genetic testing on a blood sample, but may also include may a physical exam, muscle biopsy, or other blood tests.  LONG ANSWER: Duchenne and Becker muscular dystrophy are names for the same disorder caused by genetic mutations in the DMD gene.  It is diagnosed by genetic testing performed on a blood sample. However, part of the clinical diagnosis might include a physical exam, a reveiw of you and your family's medical history, and blood tests to measure the levels of certain enzymes that indicate Duchenne or Becker muscular dystrophy. In addition, a muscle biopsy might be performed, which involves removing a small sample of muscle tissue to be analyzed under a microscope. Your doctor may choose to do one or a combination of these tests, depending on each individual's case.