Pharmacogenetics in kidney transplantation: recent updates and potential clinical applications.

Every month, new releases on the relationship between pharmacogenetic biomarkers and immunosuppressive drug therapy in kidney transplantation are published. However, the systematic clinical application of these discoveries occurs at a very slow pace, and the usefulness of knowing a patient's genotype remains an important matter of debate. This can be partially ascribed to the lack of consistency when looking at the different associations reported across several studies but also the need for a broad-spectrum view and a rigorous analysis of the relevance of the different associations observed to date. For that purpose, we performed a comprehensive analysis of the strength of the different reported genetic associations, and in this article we discuss their potential for clinical implementation in kidney transplantation. For tacrolimus, it is likely that a genotype-based drug dosage can benefit patient outcome, while for ciclosporin A, the data appear less convincing. For the mammalian target of rapamycin inhibitors, sirolimus and everolimus - given the lack of data and the absence of large prospective studies - it is premature to implement pharmacogenetics, but some novel and promising leads have recently been reported. For mycophenolate mofetil, the complex metabolic pathways of its active moiety, mycophenolic acid, complicate analysis of the various published associations. However, at present, some interesting findings can be highlighted and offer potential value to assist clinicians in decision making.