Vascular endothelial growth factor A polymorphisms and age-related macular degeneration: a systematic review and meta-analysis

PURPOSE: In the present work, the aim was to systematically review all studies about the association of vascular endothelial growth factor A (VEGF-A) polymorphisms with age-related macular degeneration (AMD) and to perform a meta-analysis. METHODS: Relevant studies were searched using PubMed, Embase, Wanfang (Chinese), VIP (Chinese), and the Chinese National Knowledge Infrastructure databases up to October, 2011. A meta-analysis was conducted using Stata software, version 11.0. RESULTS: A total of nine studies with 2,281 AMD cases and 2,820 controls met our eligibility criteria, and meta-analyses of four polymorphisms of the VEGF-A gene (rs1413711, rs833061, rs2010963, and rs3025039) were performed. This meta-analysis revealed moderate evidence supporting an association between the VEGF-A polymorphisms and AMD. For rs1413711, the TT genotype was associated with an increased risk of overall AMD (TT versus CT model, odds ratio (OR) 1.74, 95% confidence interval (CI) 1.22–2.48) and of wet AMD (TT versus CT model, OR 1.82, 95% CI 1.22–2.71; TT versus (CC+CT) model, OR 1.63, 95% CI 1.13–2.35). For rs833061, the C allele (C allele versus T allele, OR 1.72, 95% CI 1.00–2.96) and CC genotype (CC versus TT model, OR 1.77, 95% CI 1.00–3.11) were the risk factors for overall AMD, while the C allele was also associated with an increased risk of wet AMD (C allele versus T allele, OR 1.54, 95% CI 1.03–2.31). No association was observed between AMD risk and the variant genotypes of VEGF-A rs2010963 and rs3025039 polymorphisms in different genetic models. CONCLUSIONS: The results suggest the VEGF-A rs1413711 and rs833061 polymorphisms may contribute to AMD susceptibility.