Evaluation of CNTNAP2 gene polymorphisms for exfoliation syndrome in Japanese

PURPOSE To investigate the contactin-associated protein-like 2 (CNTNAP2) gene for single-nucleotide polymorphisms (SNPs) in Japanese patients with the exfoliation syndrome (XFS). METHODS One hundred and eight unrelated Japanese patients with the XFS, and 199 normal controls were studied. Genomic DNA was extracted from the leukocytes of the peripheral blood, and 8 SNPs, rs826802, rs1404699, rs7803992, rs700308, rs4725736, rs2107856, rs2141388, and rs6970064, were amplified by polymerase chain reaction (PCR), directly sequenced, and genotyped. RESULTS The allele frequencies of rs1404699 (p=8.57XE-3, odds ratio (OR)=1.59, 95% confidential intervals (CI); 1,12-2.24) and rs7803992 (p=5.43XE-4, OR=1.86, 95% CI; 1.31-2.65) were statistically significantly different between XFS and controls. In addition, there were significant differences in these genotype frequencies (p=0.0197 and 1.75XE-3). The allele and the genotype frequencies of rs2107856 and rs2141388, which were statistically significant SNPs in an earlier study, were not significantly different. CONCLUSIONS The variants, rs1404699 and rs7803992, of CNTNAP2 should be associated with XFS in the Japanese population.