Transplanting renal allografts represents the major curative treatment of chronic renal failure. Despite recent advances in immunosuppressive therapy, long-term survival of allografts remains a major clinical problem. Kidney function depends in part on transport proteins such as MRP2 (ABCC2) which facilitates renal secretion of amphiphilic exogenous and endogenous compounds. Inherited variants of genes not related to the immune system have been shown to modify the outcome after renal transplantation. We investigated whether ABCC2 gene variants in the donor kidney affect renal graft function.