spinal muscular atrophy type I Definition: the early infantile
form, characterized by profound muscle weakness and wasting with
onset at or shortly after birth; death occurs usually before 2
years of age. Autosomal recessive inheritance, caused by
mutation in the survival motor neuron gene (SMN1) on 5q. About
half of affected patients are also missing both homologues of a
neighboring gene that encodes neuronal apoptosis inhibitory
protein (NAIP), the loss of which is thought to influence the
severity of the disease. Synonym(s): familial spinal muscular
atrophy, Hoffmann muscular atrophy, infantile muscular atrophy,
infantile progressive spinal muscular atrophy, progressive
infantile spinal muscular atrophy, Werdnig-Hoffmann disease,
Werdnig-Hoffmann muscular atrophy Search Stedman's Medical
Dictionary Examples: glitazone, GI cocktail, etc.