Inborn cholestatic syndromes such as progressive familial intrahepatic cholestasis type 1 (PFIC1) or type 2 (PFIC2), with their underlying dysfunction of a phospholipid flippase (ATP8B1; ATP8B1) or the bile salt export pump (BSEP; ABCB11), respectively, may also rapidly progress to liver cirrhosis, and frequently necessitate liver transplantation [1]. The gene discussed is ATP8B1; the disease is progressive familial intrahepatic cholestasis type 1.