R102G polymorphism of the C3 gene associated with exudative age-related macular degeneration in a French population

PURPOSE Major genetic factors for age-related macular degeneration (AMD) have recently been identified as susceptibility risk factors, underlying the role of the complement pathway in AMD. Our purpose was to analyze the role of the R102G polymorphism of the complement component (C3) gene in a French population, in a case-control study. METHODS A total of 1,080 patients with exudative AMD and 406 controls were recruited and genotyped for Y402H of complement factor H (CFH), rs10490924 of age-related maculopathy susceptibility 2 (ARMS2), and R102G of the C3 gene. RESULTS The distribution of the R102G genotypes was significantly different in the AMD patients compared to controls (p=0.02). The Odds Ratio compared to C/C individuals was 1.4 (95% CI 1.1-1.8) for C/G individuals and 1.4 (95% CI 0.8-2.4) for G/G individuals. In a dominant model, the adjusted Odds Ratio for carriers of the G allele is 1.4 (95% CI 1.0-1.9; p=0.03). CONCLUSIONS Our study shows C3 to be a moderate susceptibility gene for exudative AMD in the French population.