Spinal Muscular Atrophy Type 2

**Semantic type:** Disease or Syndrome

**Definition:** An autosomal recessive condition caused by mutation(s) in the SMN1 gene, encoding survival motor neuron protein. It is characterized by onset between 3 and 15 months of age, and is intermediate in terms of severity between spinal muscular atrophy (SMA) type I and SMA type III.

**Synonyms:** - SMA2