brain, spinal cord, and nerve disorders
Spinal Muscular Atrophies (SMAs)
Diagnosis of SMAs
A doctor's evaluation Electromyography and nerve conduction studies A blood test for the abnormal gene Sometimes biopsy of a muscle Doctors usually test for spinal muscular atrophies when unexplained weakness and muscle wasting occur in young children. Because these disorders are inherited, a family history may help doctors make the diagnosis. Electromyography and Nerve Conduction Studies help confirm the diagnosis. The specific defective gene can be detected by blood tests in 95% of affected people (genetic testing). Occasionally, biopsy of a muscle is done. If there is a family history of one of the disorders, Amniocentesis can be done to help determine whether an unborn child has the defective gene. 