Myeloperoxidase G-463A polymorphism and susceptibility to coronary artery disease: a meta-analysis.

Published data on the association between the myeloperoxidase (MPO) G-463A polymorphism and coronary artery disease (CAD) are inconclusive. To derive a more precise estimation of the relationship, a meta-analysis on this topic was performed. PubMed, EMBASE and Chinese national knowledge infrastructure were searched for studies regarding the association between the MPO G-463A polymorphism and CAD. A logistic regression analysis was used to estimate the genetic effect and the possible genetic model of action. Summary odds ratios (ORs) with their corresponding 95% confidence intervals (CIs) were calculated. There was strong evidence for an association between the MPO G-463A polymorphism and CAD. The genetic model of action was most likely to be co-dominant. Overall, the data showed that AA and GA genotypes were significantly associated with reduced risk of CAD (AA vs. GG: OR=0.37, 95% CI=0.17-0.78; GA vs. GG: OR=0.73, 95% CI=0.57-0.92). In subgroup analyses by study population and sources of controls, statistically significant results were observed in the Chinese population (AA vs. GG: OR=0.21, 95% CI=0.10-0.43; GA vs. GG: OR=0.57, 95% CI=0.44-0.74) and in hospital-based control studies (AA vs. GG: OR=0.20, 95% CI=0.10-0.39; GA vs. GG: OR=0.61, 95% CI=0.48-0.77). This meta-analysis suggests that the MPO G-463A variant genotypes may be associated with decreased risk of CAD. However, given the limited number of studies and the potential biases, the influence of this polymorphism on CAD risk needs further investigation.