Introduction: Diabetic retinopathy (DR) is a medical condition caused by damage to the blood vessels of retina tissue due to diabetes mellitus. DR leads to injury in neural and vascular structures and is reported to be significantly influenced by inflammation and inflammatory mediators like cytokines. In this study, a systematic review and meta-analysis were performed to analyze the association between cytokine gene polymorphisms and DR.

Methods: We identified relevant studies from Scopus, PubMed, and Google scholar databases. Allele and genotype frequencies were pooled. Heterogeneity and publication bias were explored. The odds ratio (OR) and corresponding 95% confidence intervals (CIs) were calculated to estimate the relation.

Results: A total of 3337 cases and 4945 controls in 19 eligible studies were included in the meta-analysis. Overall, results indicated the negative association between the cytokine gene polymorphisms and DR susceptibility in the allelic model (IFN-γ (rs2430561): OR 0.64, [CI]: 0.5 to 0.82; and TGF-β (rs1800471): [OR] = 0.15, [CI]: 0.03 to 0.79); and also, in the dominant model (IFN-γ (rs2430561): OR = 0.4, [CI]: 0.22 to 0.75; and TGF-β (rs1800471): OR = 0.14, [CI]: 0.05 to 0.4).

Conclusion: The present study suggests that IFN-γ (rs2430561) and TGF-β (rs1800471) polymorphisms are associated with decreased susceptibility to DR.