At variance with the paucity of zebrafish models for the aSMase-deficient forms of NPD, various attempts have been made to model the type C form of NPD, a lysosomal storage disease distinct from sphingolipidoses that depends on cholesterol trafficking defects due to mutations in NPC1 or NPC2 genes. The gene discussed is SMPD1; the disease is lysosomal storage disease.