MMP9 SNP and MMP SNP–SNP interactions increase the risk for ischemic stroke in the Han Hakka population

OBJECTIVES: To investigate the association of eight variants of four matrix metalloproteinase (MMP) genes with ischemic stroke (IS) and whether interactions among these single nucleotide polymorphisms (SNPs) increases the risk of IS. METHODS: Among 547 patients with ischemic stroke and 350 controls, matrix‐assisted laser desorption/ionization time of flight mass spectrometry was used to examine eight variants arising from four different genes, including MMP‐1 (rs1799750), MMP‐2 (rs243865, rs2285053, rs2241145), MMP‐9 (rs17576), and MMP‐12 (rs660599, rs2276109, and rs652438). Gene–gene interactions were employed using generalized multifactor dimensionality reduction (GMDR) methods. RESULTS: The frequency of rs17576 was significantly higher in IS patients than in controls (p = .033). Logistic regression analysis revealed the AG and GG genotypes of rs17576 to be associated with a higher risk for IS, with the odds ratio and 95% confidence interval being 2.490 (1.251–4.959) and 2.494 (1.274–4.886), respectively. GMDR analysis showed a significant SNP‐SNP interaction between rs17576 and rs660599 (the testing balanced accuracy was 53.70% and cross‐validation consistency was 8/10, p = .0107). Logistic regression analysis showed the interaction between rs17576 and rs660599 to be an independent risk factor for IS with an odds ratio of 1.568 and a 95% confidence interval of 1.152–2.135. CONCLUSION: An MMP‐9 rs17576 polymorphism is associated with increased IS risk in the Han Hakka population and interaction between MMP‐9 rs17576 and MMP‐12 rs660599 is associated with increased IS risk as well.