Niemann-Pick’s is a genetic disease caused by mutations in the SMPD1 gene (generating a deficiency of aSMase leading to a progressive accumulation of SM in the organs, including the brain); or in the NPC intracellular cholesterol transporter (NPC1 or NPC2) genes (leading to alterations in cellular cholesterol trafficking) [126]. Here, SMPD1 is linked to hereditary disease.