Maciej Tarnowski,1 Sylwia Słuczanowska-Głabowska,1 Andrzej Pawlik,1 Małgorzata Mazurek-Mochol,2 Elżbieta Dembowska2 1Department of Physiology, 2Department of Periodontology, Pomeranian Medical University, Szczecin, Poland Abstract: Posttransplant diabetes mellitus (PTDM) is one of the major metabolic complications after transplantation of solid organs including the kidney. This type of diabetes mellitus affects allograft survival, cardiovascular complications and overall patient survival. The modifiable risk factors that contribute to PTDM include obesity, some viral infections (eg, hepatitis C virus, cytomegalovirus) and especially immunosuppressive drugs including corticosteroids, tacrolimus, cyclosporine and sirolimus. Currently, predisposing genetic factors have been considered important in PTDM development. The commonly evaluated genetic determinants include genes encoding transcription factors, cytokines, chemokines, adipokines, ionic channels, glucose transporters, cytochrome P450 enzymes and other enzymes metabolizing drugs, drug transporters. Unfortunately, the results of studies are inconclusive and differ between populations. There is a need for large genome-wide association study to identify the genetic risk factors associated with PTDM development. Keywords: diabetes mellitus, kidney, transplantation, gene polymorphism, SNP