Three types of PFIC have been described: 1) PFIC type 1, caused by mutations in ATP8B1 gene (also called FIC1); 2) PFIC type 2, caused by mutations in ABCB11 gene (also called BSEP) and 3) PFIC type 3, caused by mutations in ABCB4 gene (also called MDR3). Here, ATP8B1 is linked to progressive familial intrahepatic cholestasis.