Purpose: To investigate vascular endothelial growth factor (VEGF) gene polymorphisms in unrelated Taiwan Chinese patients with late age-related macular degeneration (AMD) and controls.
Design: Retrospective case-control study.
Methods: We enrolled 190 late AMD patients and 180 age-matched and gender-matched controls. Late AMD was classified as either dry (atrophic; grade 4) or wet (neovascular; grade 5) according to the International Age-Related Maculopathy Epidemiologic Study. Genomic deoxyribonucleic acid was prepared from peripheral blood obtained from all subjects. Polymerase chain reactions were used to analyze five candidate single-nucleotide polymorphisms (SNPs) in VEGF gene: +405C/G (rs2010963), -460 T/C (rs833061), +674 C/T (rs1413711), +936C/T (rs3025039), and -2578C/A (rs699947).
Results: Of the 190 late AMD patients, dry AMD was diagnosed in 104 and wet AMD in 86. Among the five candidate SNPs studied, only the +936 C/T was significantly associated with wet AMD (T allele: 30% in wet AMD vs 14% in controls; P = 1.45 x 10(-5); odds ratio, 2.61; 95% confidence interval, 1.68 to 4.07). No single haplotype was significantly associated with either late AMD or controls. Based on genotypes at both VEGF +936 C/T and the complement factor H (CFH) Y402H (rs1061170), the association of VEGF +936 C/T to AMD was significant when analyzed conditional on the presence of the CFH C risk allele and vice versa (P < .0001). The VEGF +936 C/T was in strong linkage disequilibrium with CFH Y402H (D' = 0.99).
Conclusions: Both VEGF +936 C/T and CFH Y402H polymorphisms are dependently associated with wet AMD in the Taiwan Chinese population.