ATP8B1 and hyperinsulinemic hypoglycemia, familial, 4: As an example, familial intrahepatic cholestasis 1 (FIC1) protein deficiency caused by mutations inATP8B1 (PFIC type 1) and bile salt export protein (BSEP) deficiency caused by mutations inABCB11 (PFIC type 2) have similar presentations, however liver transplantation is used more frequently in PFIC type 2 then type 16.