Interleukin-10 -1082A > G (rs1800896) polymorphism is associated with diabetic retinopathy in type 2 diabetes.

Aim: To investigate whether the -1082A > G polymorphism (rs1800896) in the interleukin-10 (IL10) gene is associated with diabetic retinopathy (DR) in Brazilians with type 2 diabetes mellitus.

Methods: This case-control study included 847 outpatients with type 2 diabetes and 145 healthy blood donors. Four hundred and two patients had no DR, 253 had non-proliferative DR (NPDR), and 192 had proliferative DR (PDR). Genotyping was done by real-time PCR.

Results: Genotype and allele frequencies were similar in patients and blood donors. In relation to the presence and severity of DR, the AA genotype was overrepresented among patients with NPDR, whereas the GG genotype was more frequent among patients with PDR. Multiple logistic regression analysis showed that the AA genotype was independently associated with increased risk of NPDR, after controlling for duration of diabetes, body mass index, and insulin use (adjusted OR = 1.50; 95% CI = 1.04-2.17). The GG genotype, however, did not remain associated with increased risk of PDR (adjusted OR = 1.49; 95% CI = 0.78-2.86).

Conclusions: This study identified, for the first time, an independent association of the -1082A > G polymorphism in the IL10 gene with NPDR in type 2 diabetes. This finding provides additional evidence supporting that genetic variants of IL10 are involved in the pathogenesis of DR.