Purpose: This study was undertaken to investigate the association between the complement factor H (CFH) gene and exudative age-related macular degeneration (AMD) in Korean patients.
Methods: Genomic DNA was isolated from the peripheral leukocytes of patients with exudative AMD (n = 114) and control subjects (n = 187). The sole criterion for exudative AMD was the presence of choroidal neovascularization. Four single-nucleotide polymorphisms (SNPs: -275C>T, I62V, Y402H, and IVS15) located in promoter, exon 2, exon 9, and intron 15 of the CFH gene were genotyped by PCR-based direct sequencing.
Results: The frequency of the C allele of Y402H (AMD, 10.5%; control, 6.5%) was found to be lower in Koreans than in Caucasians. In the present study, the difference between the frequencies of Y402H in cases and control subjects did not reach statistical significance (P = 0.071). However, the frequencies of the major alleles of three SNPs (-275C>T, I62V, and IVS15) were significantly different in patients and control subjects, and these SNPs were found to be separately associated with an elevated risk of exudative AMD. Seven haplotypes were identified in Koreans. Haplotype analysis showed that two haplotypes (TGTG, CGTG) conferred significantly higher risks of exudative AMD (P = 0.013, 0.035), and one haplotype (CATA) was significantly protective (P < 0.001).
Conclusions: In Korean subjects, CFH polymorphism appears to be a considerable hereditary contributor to exudative AMD. Y402H polymorphism which has been suggested to be a major risk factor of AMD in Caucasians was found to be only marginally associated with exudative AMD with low frequency, whereas three adjacent SNPs in the CFH gene were significantly associated with AMD in Koreans.