Supplementary Material for: Meta-Analysis of MMP9 –1562C/T and the Risk of Coronary Heart Disease

Introduction: Previous case-control studies have suggested that the –1562C/T and R279Q polymorphisms of the matrix metalloproteinase 9 gene (MMP9) are associated with coronary heart disease (CHD). However, other studies do not confirm these relationships. The objective is to assess these relationships using meta-analysis. Methods: Databases, including PubMed and ScienceDirect, were searched to access the genetic association studies. Then data were extracted. Pooled odds ratio (OR) and 95% confidence interval (CI) were calculated. Moreover, subgroup and sensitive analysis were performed. Results: The meta-analysis of the –1562C/T polymorphism included 12 studies with 8,336 cases and 3,984 controls. The –1562T allele was significantly associated with CHD (OR 1.25, 95% CI 1.08–1.45, p = 0.004). There was heterogeneity among the 12 studies (I2 = 61%, p = 0.003). The overall results were consistent and were not changed substantially by the removal of any data set. The meta-analysis of the R279Q polymorphism, including 6 studies with 6,983 cases and 3,282 controls, showed that the R279Q polymorphism was not associated with CHD (p = 0.16). Conclusions: The synthesis of available evidence supports the fact that the MMP9 –1562C/T polymorphism is a risk factor for CHD.