Loss-of-function (LOF) mutations in ABCG5 or ABCG8 are linked to sitosterolemia, a rare autosomal recessive disease, while several other missense mutations are also associated with other lipid disorders, such as gallstone formation or elevated low-density lipoprotein (LDL) cholesterol [23,24,25,26,27,28]. This evidence concerns the gene ABCG5 and sitosterolemia.