The potential association of heat shock protein 70-2 + 1267 A/G gene polymorphism with nephropathy in type II diabetic patients

Objective The aim of the study was to assess the association between heat shock protein (HSP) 70-2 + 1267 A/G polymorphism and diabetic nephropathy (DN) in type II diabetes mellitus. Background DN is a life-threatening microvascular complication of type II diabetes. Oxidative stress plays a main role in its pathogenesis. As a consequence, a cellular adaptive response occurs requiring functional chaperones, so that the induction of HSPs is a maintained response in counteracting this oxidative stress. HSP70-2 + 1267 A/G and HSP70-hom + 2437 T/C polymorphisms may play an important role in susceptibility to and/or progression of DN. Patients and methods Sixty type II diabetic patients (30 patients with DN and 30 patients free of DN) and 20 healthy individuals, as the control group, were selected. Participants were genotyped for the HSP70-2 + 1267 A/G and HSP70-hom + 2437 T/C polymorphisms by PCR/restriction fragment length polymorphism. Results There was significant difference for HSP70 - 2 + 1267 A/G polymorphism. GG genotype and G allele were more frequent in the DN group versus other groups, whereas there was no significant difference in genotype and allele distributions among the three studied groups for the HSP70-hom polymorphism. On comparing diabetics with nephropathy versus diabetics without nephropathy, the odds ratio of the risk allele (G) of HSP70 - 2 + 1267 was 4.60 (95% confidence interval 2.09-10.12) and was 0.45 (95% confidence interval 0.15-1.42) for the risk allele (C) of HSP70-hom + 2437 T/C polymorphism. Conclusion HSP70 - 2 + 1267 A/G polymorphism is associated with renal complications in type II diabetic patients and may be useful in identifying patients with increased risk for DN.