In comparison, the subtle deficiency of Sptlc2 mRNA in the KIN mouse is associated with the peripheral neuropathy in HSAN1, and the marked deficit of aSMase protein in the KIN mouse is associated with the neuronopathic NPC disorder, so both events in SCA2 may contribute to pathogenesis, but they mediate two relatively unspecific clinical aspects. This evidence concerns the gene SMPD1 and peripheral neuropathy.