Association of donor TNFRSF6 (FAS) gene polymorphism with acute rejection in renal transplant patients: a case-control study

Background. Genetic factors other than HLA have been reported to be associated with the outcome of organ transplantations. Because binding of FasL to its receptor Fas could play an important role in tubulitis and in the death of graft tubular epithelial cells during kidney allograft rejection, a gene polymorphism recently identified in position –671 in the promoter of the TNFRSF6 gene coding for Fas was investigated in donors. Methods. A case-control study was performed within a cohort of non-hyperimmunized adult patients who had received cadaveric kidney transplants based on the occurrence or absence of acute cellular rejection in the first 6 months after renal transplantation. Each recipient from the acute rejection group (n ¼ 35) was matched for age (± 5 years) and number of HLA-DR mismatches with two recipients within the non-acute rejection group (n ¼ 70). Results. The TNFRSF6-GG genotype was more frequent in donors in the group without rejection episodes. In contrast, patients who received a kidney from a TNFRSF6-A carrier were more likely to experience acute rejection episodes (relative risk nearly 2.1). Conclusion. This study suggests that donor TNFRSF6 polymorphism directly or indirectly influences acute kidney rejection episodes.