ABCB11 and Pseudoxanthoma elasticum: These include ABCA1 (HDL-deficiency, Tangier disease) [89,90], ABCB4 (progressive familial intrahepatic cholestasis type 3; PFIC3) [91], ABCB11 (PFIC2) [92], ABCC2 (Dubin-Johnson syndrome) [93,94], ABCC6 (pseudoxanthoma elasticum, general arterial calcification of infancy) [95] and ABCG2 (gout) [96].