Association of VEGF gene polymorphisms with diabetic retinopathy: a meta-analysis.

Background: Studies on the association of vascular endothelial growth factor (VEGF) gene -460T/C and -2578C/A polymorphisms with diabetic retinopathy (DR) have reported conflicting results. The aim of the present study was to assess the association by using meta-analysis.

Methods: A systematic search of electronic databases (PubMed, EMBASE, Elsevier Science Direct, ISI Web of Science, CBM, CNKI and VIP) was carried out until Sept 18, 2013. The pooled odds ratios (ORs) and their corresponding 95% confidence intervals (CIs) were used to assess the strength of the association.

Results: Eleven studies (-460T/C: 6 studies including 932 cases and 722 controls; -2578C/A: 6 studies including 1,071 cases and 1,137 controls) were involved in this meta-analysis. Significant association was found for -460T/C polymorphism (C versus T: OR=1.48, 95%CI=1.07-2.05, P=0.02; TC+CC versus TT: OR=1.78, 95%CI=1.02-3.12, P=0.04; CC versus TT+TC: OR=1.76, 95%CI=1.10-2.81, P=0.02), but not for -2578C/A polymorphism (P>0.05). Similar results were found in the subgroup analysis.

Conclusions: This meta-analysis demonstrates that DR is associated with VEGF gene -460T/C polymorphism, but not -2578C/A polymorphism. Further case-control studies based on larger sample size are still needed, especially for -2578C/A polymorphism.