AIM: To analyze the association of extracellular matrix metalloprotease 9(MMP-9)single nucleotide polymorphism(SNP)with genetic susceptibility of primary angle-closure glaucoma(PACG)in a Han Chinese population.

METHODS: Totally 200 PACG patients(PACG group)and 200 healthy people(normal control group)were collected in our hospital from January 2014 to December 2016. Peripheral venous blood was collected and extracted for genomic DNA, the polymerase chain reaction-restriction fragment length polymorphism technique(PCR-RFLP)was applied to detect the alleles and genotypes of rs2250889, rs2274755 and rs2664538 sites in MMP-9 gene. The frequency distribution of alleles and genotypes in the two groups were calculated by chi-square test, and its association with genetic susceptibility of PACG was analyzed.

RESULTS: There were no statistical differences in age, gender, body mass index, diastolic blood pressure and systolic blood pressure in the two groups(P>0.05). The genotype frequencies of rs2250889, rs2274755 and rs2664538 sites in MMP-9 gene were in line with Hardy-Weinberg equilibrium. The genotype and allele frequency distribution of rs2250889 and rs2664538 sites were significantly different between the PACG group and the normal control group(P<0.05), while the genotype and allele frequency distribution of rs2274755 sites in the two groups had no statistical difference(P>0.05). The subjects whose rs2250889 site carrying the CC genotype was susceptible to PACG. Similarly, the rs2664538 site carrying the GG genotype was susceptible to PACG.

CONCLUSION: The rs2250889 and rs2664538 polymorphisms of MMM-9 are correlated with the risk of PACG in a Han Chinese population, while the rs2274755 polymorphism is not related to genetic susceptibility of PACG.