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autosomal recessive disease in which the degeneration of spinal nerve cells and brain nerve cells leads to atrophy of skeletal muscles and flaccid paralysis; death usually occurs in early childhood

autosomal recessive disease in which the degeneration of spinal nerve cells and brain nerve cells leads to atrophy of skeletal muscles and flaccid paralysis; death usually occurs in early childhood

A group of recessively inherited diseases that feature progressive muscular atrophy and hypotonia. They are classified as type I (Werdnig-Hoffman disease), type II (intermediate form), and type III (Kugelberg-Welander disease). Type I is fatal in infancy, type II has a late infantile onset and is associated with survival into the second or third decade. Type III has its onset in childhood, and is slowly progressive. (J Med Genet 1996 Apr:33 (4):281-3)