[MIM*257220] a rare inherited lipid storage disorder, affecting viscera and central nervous system, inherited as an autosomal recessive. There are two types of disease, with same clinical manifestations and biochemical abnormalities, resulting from abnormalities in two separate genes, NPC-1, the major locus, and NPC-2, the minor locus; then two types have identical clinical and biochemical phenotypes. Cells from NPC patients are defective in the esterification and release of cholesterol from lysosomes; lysosomal sequestration of LDL-derived cholesterol, including delayed down regulation of LDL uptake and de novo synthesis occur.