The association of polymorphisms in promoter region of MMP2 and MMP9 with recurrent spontaneous abortion risk in Chinese population

This study aimed to reveal the genetic association between polymorphisms in promoter region of matrix metalloproteinase 2 (MMP2) and matrix metalloproteinase 9 (MMP9) and the risk of recurrent spontaneous abortion (RSA) in Chinese population. A total of 129 RSA patients and 116 relative controls were selected and the genotyping of polymorphism was conducted by polymerase chain reaction with sequencing. Genotype distribution of polymorphism in the control group was tested the status of Hardy-Weinberg equilibrium and then, genotype frequencies were compared between the case and control groups by chi-squared test. Odds ratio (OR) with the corresponding 95% confidence interval (95% CI) was computed to express the risk of RSA caused by polymorphism. Moreover, the linkage disequilibrium of polymorphisms in MMP2 was analyzed by Haploview software. CT genotype and T allele of rs243865 in MMP2 were significantly associated with the increased susceptibility to RSA in Chinese population (CT vs. CC: OR = 1.926, 95% CI = 1.101-3.368; T vs. C: OR = 1.751, 95% CI = 1.146-2.676). Similarly, CT genotype carriers of rs3918242 in MMP9 were obviously more in RSA patients than that of the controls (P = .037), which indicated it was associated with the risk of RSA occurrence (OR = 1.760, 95% CI = 1.034-2.995). So was T allele in RSA development (OR = 1.595, 95% CI = 1.061-2.398). Haplotypes C-T and T-C were also the risk factors of RSA (OR = 1.673, 95% CI = 1.103-2.536; OR = 2.171, 95% CI = 1.372-2.436). MMP2 rs243865 and MMP9 rs3918242 polymorphisms are significantly associated with the risk of RSA in Chinese population.