hTERT, BICD1 and chromosome 18 polymorphisms associated with telomere length affect kidney allograft function after transplantation

Abstract

Background/aims: It has been confirmed that telomere length (TL) correlates with chronological donor age and that telomere shortening is accelerated in allografts. The aim of this study was to analyse the associations between graft rs2735940 hTERT and rs2630578 BICD1 gene polymorphisms and rs7235755/rs2162440 chromosome 18 polymorphisms, relative TL and kidney function after transplantation.

Methods: The study enrolled 119 Polish Caucasian kidney allograft recipients (64M/55F, mean age 47.3±14.0 years). The relative TL was assessed in biopsy specimens. To identify genotypes of the studied polymorphisms, real-time PCR was performed.

Results: The graft rs2735940 hTERT gene polymorphism TT genotype was associated with a significantly lower risk of delayed graft function (DGF) (TT vs. TC+CC; OR=0, p=0.009) and significantly shorter TL in the '0' biopsy (TT vs. CC: 207±153 vs. 400±161, p=0.036). The graft rs2630578 BICD1 gene polymorphism CC genotype was associated with lower creatinine concentrations in the first month (CC vs. GC: 1.11±0.06 vs. 2.0±1.25 mg/dL, p=0.03). The AA genotype of the graft rs7235755 chromosome 18 polymorphism was associated with longer relative TL in specimens collected 12 to 60 months after transplantation (AA vs. GG+GA p=0.04; AA vs. GG: 489±152 vs. 246±145, p=0.035) and the presence of A allele was associated with higher creatinine concentrations one month after transplantation (GA+AA vs. GG p=0.026; GA vs. GG: 2.18±1.59 vs. 1.76±0.88 mg/dL, p=0.02). It was found that shorter TL in the first six months was associated with higher creatinine concentrations 12 and 18 months after transplantation (Rs=-0.32; p=0.07 and Rs=-0.54; p=0.006, respectively).

Conclusions: Graft rs2735940 hTERT and rs2630578 BICD1 gene polymorphisms and rs7235755/rs2162440 chromosome 18 polymorphisms, apart from the association with TL, affect early kidney function after transplantation. Relative TL correlated negatively with creatinine concentrations, allowing the use of TL as a predictor of long-term kidney function.