Replication study supports CTNND2 as a susceptibility gene for high myopia

The CTNND2 gene is located in the linkage interval of high myopia locus MYP16 and two single-nucleotide polymorphisms (SNPs; rs6885224 and rs12716080) in CTNND2 were recently shown to associate with high myopia. This study evaluated such associations in an independent case-control series.

A total of 2773 unrelated individuals were enrolled in this study, including 1203 subjects with high myopia (spherical refraction at each meridian ≤ -6.00 D), 615 subjects with moderate myopia (-6.00 D < spherical refraction ≤ -4.00 D), and 955 controls (-0.50 D to +1.00 D, spherical equivalent). Genomic DNA was prepared from venous leukocytes. SNPs rs6885224 and rs12716080 in CTNND2 were determined by Sanger sequencing. Allele and genotype frequencies of the SNPs were compared between cases and controls by χ² test (α = 0.05).

One SNP, rs6885224, in CTNND2 showed significant differences in genotype and allele frequencies between high myopia and controls (genotype P = 2.17E×10(-5), allele P = 5.29E×10(-6), odds ratio [OR] = 0.69, 95% confidence interval [CI] = 0.591-0.812), as well as between moderate myopia and controls (genotype P = 0.009, allele P = 0.005, OR = 0.765, 95% CI = 0.633-0.924). rs12716080 showed no statistical difference between myopias and controls.

These results confirmed the strong association between CTNND2 polymorphism and myopia. The minor allele C of rs6885224 was protective against myopia in this study but was a risk allele in a previous study.