Dubin johnson syndrome is caused by mutation of:

F1C1 is defective in progressive familial intrahepatic cholestasis type 1 (PFIC1) and benign recurrent intrahepatic cholestasis type 1 (BRIC1) BSEP is defective in PFIC2 and BRIC2 Mutations of MRP2 (ABCC2) cause the Dubin-Johnson syndrome, an inherited form of conjugated hyperbilirubinemia A defective MDR3 (ABCB4) results in PFIC3 The cystic fibrosis transmembrane regulator (CFTR, ABCC7) located on bile duct epithelial cells but not on canalicular membranes is defective in cystic fibrosis This is a difficult area to understand Reference: Harrisons Principles of Internal Medicine, 18th Edition, Page 2616