Which assessment confirms the subtype of muscular dystrophy?

• A. EMG
• B. Nerve conduction study
• C. Genetic testing
• D. MRI

Answer: (C)

The precise subtype of muscular dystrophy is defined by the specific gene mutation causing it. Genetic testing directly looks for pathogenic changes in dystrophy-related genes and can confirm exactly which subtype a person has. This level of certainty is what makes genetic testing the best choice for confirming subtype, since it identifies the responsible gene rather than just describing symptoms or muscle changes.

Other assessments describe the disease’s effects but don’t reveal the exact genetic cause. EMG and nerve conduction studies assess muscle and nerve function and can show a myopathic pattern, but they don’t indicate which gene is mutated. MRI shows how muscles are affected and the pattern of involvement, which can be suggestive but is not definitive for subtype. Muscle biopsy can show dystrophic changes and may offer clues, but confirmation of the precise subtype relies on identifying the gene mutation itself through genetic testing.