Evaluation of lysyl oxidase-like 1 gene polymorphisms in pseudoexfoliation syndrome in a Korean population

PURPOSE: The purpose of this study was to evaluate association profiles of lysyl oxidase-like 1 (LOXL1) gene polymorphisms with pseudoexfoliation syndrome (XFS) in a Korean population. METHODS: A total of 110 Korean patients with XFS and 127 control subjects were included in this study. Genotypes of three single nucleotide polymorphisms (SNPs) of LOXL1 (rs1048661, rs3825942, and rs2165241) were analyzed with direct sequencing, and a case-control association study was performed. Genotype frequencies of each SNP were compared according to the XFS phenotypes. RESULTS: All three SNPs were significantly associated with XFS. The T allele at rs1048661 (odds ratio [OR]=14.29, 95% confidence interval [CI]=6.25–33.3) and the C allele at rs2165241 (OR=7.14, 95% CI=1.59–33.3) were risk alleles in Korean subjects, which was consistent with findings in other Asian populations. However, our findings were opposite to results from Caucasian populations in which the risk alleles at rs1048661 and rs2165241 were G and T, respectively. At the rs3825942, the G allele (OR=12.50, 95% CI=2.94–50.0) was a risk allele for XFS, which was similar to results from most other ethnic groups except black South Africans in whom the A allele increased the risk. In the haplotype analysis, the T-G-C haplotype composed of all three risk alleles was significantly overrepresented in XFS and conferred an 11.36 fold (95% CI=5.97–23.49) increased likelihood of XFS. There was no significant association between the genotype frequencies of the three SNPs and the XFS phenotypes. CONCLUSIONS: Three SNPs of LOXL1 (rs1048661, rs3825942, and 2,165,241) are highly associated with XFS in a Korean population. The risk alleles of these SNPs were similar to those of other Asian populations, such as Japanese or Chinese, but differed from non-Asian populations, suggesting that still unidentified genetic or environmental factors may contribute to disease expression.