Purpose
To evaluate the relationship among single nucleotide polymorphisms (SNPs) in component pathway genes, demographic and behavioral characteristics, and age-related macular degeneration in a Chinese population.
Methods
Case-Control study. Patients with neovascular AMD or early AMD and normal control subjects were recruited through a community-based eye disease-screening program in urban Beijing and among the outpatients visiting the Beijing Tongren Hospital. Twenty-one single nucleotide polymorphisms (SNPs) in 7 genes in the complement pathway, as well as ARMS2/HTRA1 genes were screened. Genotyping for SNPs were performed using methods of PCR followed by allele-specific restriction enzyme digestion or Sequenom MassARRAY technology. Statistical analysis was performed using the R statistical analysis package. Multivariate logistic regression analysis was performed to evaluate the relationships between AMD and genotypes as well as the environment factors.
Results
A total of 490 patients with AMD (343 with early AMD and 147 with neovascular AMD) and 202 controls were enrolled in the study. Significant associations of neovascular AMD were noted with allele frequency of five SNPs rs800292, rs1329428, rs1410996, rs2274700 and rs3753394 in the CFH gene (p<0.001), as well as one variant rs1005510 in SERPING1 gene (p=0.039). However, none of the complement pathway variants was associated with early AMD. In multivariate logistic regression, significant association of neovascular AMD remained with homozygous genotype of SNPs rs800292 (OR=15.01, 95%CI: 2.40-93.98) in CFH gene and rs1005510 (OR=0.15, 95%CI: 0.03-0.82) in SERPING1 gene. In addition, marginal significant association of SNP rs2072633 in CFB gene was found with large drusen (OR=0.42, 95%CI: 0.23-0.78) and neovascular AMD (OR=0.46, 95%CI: 0.24-0.92) under heterozygote genotype. SNP rs11200638 in HTRA1 gene was significantly associated with both early and neovascular AMD groups (p= 0.018 and 1.1×10-7, respectively).
Conclusions
The data confirmed previous observation that the complement system may have a significant role for the development of neovascular AMD. However, these associations were not detected in patients with early AMD.
Keywords: 412 age-related macular degeneration •
539 genetics