BSEP mutations are the basis of cholestatic liver diseases of varying severity ranging from milder forms as intrahepatic cholestasis of pregnancy (ICP)3, 4, 5 or benign recurrent intrahepatic cholestasis type 2 (BRIC-2)6, 7 to progressive familial intrahepatic cholestasis type 2 (PFIC-2) often resulting in end-stage liver disease in early childhood necessitating liver transplantation2, 8, 9, 10, 11. Here, ABCB11 is linked to progressive familial intrahepatic cholestasis type 2.