PURPOSE. A case-control study in a relatively large cohort of highly myopic patients was conducted to explore the genetic background of the occurrence of choroidal neovascularization (CNV) secondary to high myopia.
METHODS. We evaluated three single nucleotide polymorphisms (SNPs) from two candidate genes: pigment epithelium-derived factor (PEDF) and complement factor I (CFI). The SNPs were selected based on previous reports. A total of 1082 unrelated highly myopic (i.e., axial length 26 mm in at least one eye) Japanese individuals with CNV (n = 478) and without CNV (n 557) who were 50 years of age and older were genotyped by using an SNP assay. Multivariable logistic regression was conducted to adjust for age, sex, and axial length.
RESULTS. Compared with individuals without CNV, subjects with CNV were significantly older (P < 0.01) and more likely to be female (P < 0.01), but they did not have a significantly different axial length (P = 0.50). We did not find an association between the three SNPs and the occurrence of CNV. However, a subanalysis using extremely myopic patients (case: control = 284:317) revealed a marginal association of rs12603825 in the PEDF gene (P = 0.045). The contribution of rs1136287 in CFI was not found in any analysis.
CONCLUSIONS. We demonstrated a marginal association of the PEDF SNP, rs12603825, with myopic CNV in extremely myopic patients. A further study using a larger cohort might elucidate a significant association; rs1136287 in CFI is less likely to be associated in Japanese individuals.