Among progressive familiar intrahepatic cholestasis (PFIC) syndromes, only PFIC1 patients showed reduced hepatic and ileal FXR levels.49,50 Acquired cholestatic conditions, such as drug-induced liver injury and intrahepatic cholestasis of pregnancy (ICP), have also been associated with FXR dysfunction. The gene discussed is NR1H4; the disease is progressive familial intrahepatic cholestasis type 1.