ABSTRACT
Byler disease (a form of progressive familial intrahepatic cholestasis [PFIC]) is viewed by many as the prototype for genetic forms of biliary transport disorder. It was first described in the 1960s [3,4] as a cholestatic disease which affected members of the Amish community who were direct descendants of Jacob Byler and Nancy Kaufmann. This couple emigrated to Pennsylvania in the late eighteenth century and were originally from Switzerland.
