Complement factor H Val62Ile variant and risk of age-related macular degeneration: A meta-analysis

PURPOSE To evaluate the precise association of complement factor H (CFH) Val62Ile polymorphism with age-related macular degeneration (AMD) susceptibility. METHODS We performed a meta-analysis using databases including PubMed, EMBASE, and Web of Science to find relevant studies. Summary odds ratios (ORs) and 95% confidence intervals (CIs) were estimated using fixed-effect and random-effects models. The inconsistency index (I(2)) was used to assess heterogeneity. Funnel plots and Egger's test were used to evaluate publication bias. Sensitivity analysis was also performed. RESULTS Fourteen studies including 4,438 patients with AMD and 6,099 controls based on the search criteria were involved in the meta-analysis. In overall populations, the pooled OR(1) for genotype GA+GG versus homozygous genotype AA was 2.28 (95% confidence interval (CI): 1.48-3.52), the OR(2) of heterozygous genotype GA versus AA was 1.58 (95% CI: 1.13-2.19), the OR(3) of homozygous genotype GG versus AA was 2.90 (95% CI: 1.95-4.30), and the OR(4) of allele G versus A was 1.77 (95% CI: 1.43-2.21). In Asian populations, our results provided substantial evidence that the Val62Ile variant was significantly associated with AMD (OR(4) = 1.85, 95% CI: 1.63-2.09). However, in Caucasian populations, no significant association of Val62Ile with AMD was established in all circumstances. CONCLUSIONS Our analysis provides substantial evidence that the Val62Ile variant is significantly associated with AMD in Asian populations. However, our results have demonstrated no link between the Val62Ile polymorphism and AMD in Caucasian populations.