Purpose: The objective of this study was to investigate whether genetic variations in the paired box 6 (PAX6) gene are associated with high myopia in Japanese subjects.
Methods: A total of 1,307 unrelated Japanese patients with high myopia (axial length ≥26 mm in both eyes) and two independent control groups were evaluated (333 cataract patients without high myopia and 923 age-matched healthy Japanese individuals). We genotyped three tag single-nucleotide polymorphisms (SNPs) in PAX6: rs2071754, rs644242, and rs3026354. These SNPs provided 100% coverage of all phase II HapMap SNPs within the PAX6 region (minor allele frequency ≥0.10; r(2) threshold: 0.90). Chi-square tests for trend and multivariable logistic regression were conducted.
Results: Genotype distributions in the three SNPs were in accordance with the Hardy-Weinberg equilibrium. After adjusting for age and sex, evaluation of cataract control showed a marginal association with high myopia in rs644242 (odds ratio [95% confidence interval]=0.69 [0.49-0.96], p=0.026), and a significant association was observed in healthy Japanese controls (0.79 [0.66-0.96], p=0.015). We pooled two control cohorts to evaluate the association. This analysis revealed a strong association between rs644242 and high myopia (0.78 [0.65-0.92], p=0.0045). The rs644242 A allele was a protective allele for development of high myopia. Subanalysis also revealed that rs644242 was significantly associated with extreme high myopia (0.78 [0.64-0.95], p=0.0165). The other two SNPs did not show a significant association with this condition.
Conclusions: The current study showed a significant association of PAX6 with high and extreme myopia in Japanese participants. The A allele of rs644242 is a protective allele.