This study was to investigate the association of genetic polymorphisms in complement component 2 (C2), complement factor B (CFB) and complement component 3 (C3) with exudative age-related macular degeneration (AMD) in a Korean population and the gene–gene and gene–environment interactions in the development of AMD. A total of six SNPs that are located in the C2 (rs547154, rs9332739), CFB (rs4151667, rs641153) and C3 (rs1047286, rs2230199) genes were genotyped in 350 samples comprised of 153 cases, 197 controls. The risk allele frequencies for rs547154 in C2 were 6.54% and 8.12% in AMD patients and controls. Those for rs641153 in CFB were 6.54% and 8.63% in AMD patients and controls. The risk allele frequency for rs9332739 in C2 (AMD, 0.65%, control, 2.03%) and rs4151667 in CFB (AMD, 0.65%, control, 1.78%) was very low. The protective allele of four SNPs was not significantly associated with decreased risk for AMD (P = 0.427, P = 0.199, P = 0.312, P = 0.303, respectively). The homozygotes for the protective allele of four SNPs were not significantly associated with decreased risk for AMD (P = 0.324, P = 0.474, P = 0.309, P = 0.411, respectively). The genetic effect of two SNPs in C3 could not be investigated because the variants were not observed. There was no evidence to support an interaction of these SNPs with LOC387715/HTRA1 variants or with environmental exposure like smoking. In conclusion, the genetic effect of C2, CFB and C3 polymorphisms, which are known to be important for AMD in Caucasian, were not significant in the Korean population. The low minor allele frequency of these SNPs in Koreans might have affected the results of this study. Ethnic differences in the roles of C2, CFB and C3 in conferring a risk of AMD should be further investigated.Highlights
★ A series of genes involved in AMD were discovered in the complement pathway. ★ The association of six SNPs in C2, CFB and C3 with AMD was investigated in Koreans. ★ The allele and genotype frequency of six SNPs in C2, CFB and C3 was low in Koreans. ★ The genetic effect of C2, CFB and C3 polymorphisms were not significant in Koreans.