For example, specific missense variants of the NIPA1 (non-imprinted in PWS/AS 1; OMIM # 608145) gene are known to cause autosomal dominant hereditary spastic paraplegia and postural disturbance; repeat expansions have recently been associated with amyotrophic lateral sclerosis [6,7]. The gene discussed is NIPA1; the disease is amyotrophic lateral sclerosis.