Association between polymorphism of optic disc related genes and susceptibility to primary open angle glaucoma in Inner Mongolia

Abstract

Objective: To explore the relationship between the polymorphism of optic disc related genes and the susceptibility to primary open angle glaucoma (POAG) in Inner Mongolia.

Methods: A retrospective study was adopted to include 108 patients who were diagnosed as POAG in six hospitals in Hohhot and Baotou from January of 2014 to December of 2016 (POAG group). At the same time, 120 healthy examinees were included in the control group. 1-2 ml of whole blood was collected by use of EDTA anticoagulation tubes from each patient in these two groups. It was required to fully mix EDTA with whole blood in order to extract genomic DNA and place it in the -20°C refrigerator. Mass spectrometry was used to identify the genotype of single nucleotide polymorphism (SNP) of RFTN1 (rs690037), ATOH7 (rs7916697, rs3858145), CDC7 (rs1192415), CDKN2B (rs1063192) and SIX (rs10483727) in 108 POAG patients and 120 normal controls. χ² test and binary logistic regression were used to analyze the relationship between the genetic polymorphism and the occurrence of POAG.

Results: The frequency of G allele at CDKN2B (rs1063192) in POAG group was significantly higher than that in the control group (27% vs. 17%), and the difference was of statistical significance [odds ratio (OR) = 1.824, 95% confidence interval (CI): 1.163-2.861, p = .008]; As to the comparison in the frequency of allele at the other 7 SNPs between the two groups, the differences were statistically significant (all p > .05). Additive and dominant models at rs1063192 indicated that the individuals with G allele were more susceptible to POAG, and the difference was of statistical significance (p < .05), and recessive models showed that the risk in the individuals with A allele was not significantly reduced, and the difference was of no statistical significance (p > .05). There was no statistically significant difference in the distribution of genotypes at other SNPs between POAG group and the control group (p > .05).

Conclusions: The genetic polymorphism of CDKN2B (rs1063192) is associated with the susceptibility to POAG, and G allele may increase the risk for POAG.