Interestingly, when FXR was selectively overexpressed in the intestine of various mouse models of intrahepatic and extrahepatic cholestasis (i.e. bile duct ligation, α-naphthyl isothiocyanate treatment, and Mdr2 knockout mice), bile acid pool size was substantially reduced and cholestasis improved in these models37. The gene discussed is NR1H4; the disease is cholestasis.