About the Disease

Spinal muscular atrophy (SMA) is a group of hereditary diseases that progressively destroy motor neurons that control essential muscle activity such as speaking, walking, breathing and swallowing. It is a rare disease that affects the nervous system. Subtypes include SMA type 0, SMA type I (Werdnig-Hoffmann disease), SMA type II (Dubowitz disease), SMA type III (Kugelberg-Welander disease), and SMA type IV.

Source: National Institutes of Health