Multiple Gene Polymorphisms Associated with Exfoliation Syndrome in the Uygur Population

BACKGROUND: Our previous data suggested that three single-nucleotide polymorphisms (SNPs), rs1048661, rs3825942, and rs2165241, of the lysyl oxidase-like 1 gene (LOXL1) are significantly associated with exfoliation syndrome (XFS) and exfoliation glaucoma (XFG). The following study investigated other SNPs that potentially effect XFS/XFG. METHODS: A total of 216 Uygur patients diagnosed with XFS/XFG, and 297 Uygur volunteers were admitted to the First Affiliated Hospital at Xinjiang Medical University between January 2015 and October 2017. Blood samples were collected by venipuncture. Alleles and genotypes of LOXL1, TBC1D21, ATXN2, APOE, CLU, AFAP1, TXNRD2, CACNA1A, ABCA1, GAS7, and CNTNAP2 were analyzed by direct sequencing. RESULTS: The allele G of rs41435250 of LOXL1 was a risk allele for XFS/XFG (P < 0.001), whereas the allele G of rs893818 of LOXL1 was a protective allele for XFS/XFG (P < 0.001). After adjusting all data for age and gender, the following results were obtained: the frequency of genotype CC for rs7137828 of ATXN2 was significantly higher in XFS/XFG patients than in controls (P = 0.027), while no significance was found with reference to the frequency of genotype TT. The frequency of genotype GG for rs893818 of LOXL1 (P < 0.001) and the frequency of genotype AA were both significantly higher in XFS/XFG groups compared to the control group (P < 0.001). In addition, the frequency of genotype TT for rs41435250 of LOXL1 was higher in XFS/XFG patients than in controls (P = 0.003), while no significant difference was found with reference to the frequency of genotype GG after adjusting for age and gender. In addition, the haplotypes G-A/T-G/G-G for rs41435250 and rs893818 were significantly associated with XFS/G. CONCLUSIONS: With reference to LOXL1, the rs41435250 resulted as a risk factor and rs893818 as a protective factor for XFS/XFG in the Uygur populations. Meanwhile, the rs16958445 of TBC1D21 and the rs7137828 of ATXN2 have also shown to be associated with pathogenesis of XFS/XFG.