Abstract
Purpose: :
Recent studies in US and UK individuals have shown that single nucleotide polymorphisms (SNPs) in the complement C3 gene are associated with age-related macular degeneration (AMD). The C3 gene is a key regulator in the alternative complement activation pathway occurring downstream of the AMD associated Complement Factor H gene (CFH). We examined the potential association of a number of C3 SNP genotypes with AMD in a cohort of older Australians.
Methods: :
A total of 576 cases with AMD and 173 ethnically matched controls were available for this study. All participants completed a standard questionnaire, were given a fundus examination, and provided a blood sample for DNA extraction. Alleles were determined for the SNPs rs1047286, rs2230204, rs11085197, rs2230199, res2547438 and rs432823 by a MALDI-TOF based approach followed by statistical analysis.
Results: :
Three SNPs of the C3 gene were associated with AMD. The presence of at least one T allele from rs1047286 (odds ratio (OR) 1.45, 95% confidence intervals (95%CI) 1.02, 2.07, p=0.04), at least one G allele from rs11085197 (OR 1.46, 95%CI 1.02, 2.09, p=0.04) and at least one G from rs2230199 (OR 1.48, 95%CI 1.04, 2.11, p=0.03) were all significantly associated with an increased risk of AMD. Based on genotype, only the GG homozygote of rs2230199 was significantly associated with AMD (OR 2.74, 95%CI 1.04, 7.20, p=0.04).
Conclusions: :
The findings presented for SNP rs2230199 are similar to those of previous studies but also indicates that other SNPs in this gene are likely associated with AMD.
Keywords: age-related macular degeneration • genetics • inflammation