ATP8B1 and progressive familial intrahepatic cholestasis type 1: Two forms of inherited cholestasis, benign recurrent intrahepatic cholestasis type 1 (BRIC1) and progressive familial intrahepatic cholestasis type 1 (PFIC1) were previously mapped to 18q21 and haplotype analysis was then used to identify the mutated gene as FIC1 (familial intrahepatic cholestasis 1), also known as ATP8B1 [148].