Currently, mutations in KIF1A are listed as associated with three disorders in the OMIM database: hereditary sensory and autonomic neuropathy type 2 (HSAN2) with a recessive pattern; mental retardation type 9 (MRD9) with dominant inheritance; and SPG30 with either dominant or recessive inheritance. The gene discussed is KIF1A; the disease is hereditary sensory and autonomic neuropathy type 2.