Association between gene polymorphisms on chromosome 7 and the risk of ischemic stroke: a meta-analysis

Background: Ischemic stroke (IS) caused by thrombotic or the decrease of cerebral blood flow is one of the most prevalent health problems over the world. The cause of IS has not been clarified yet, but many risk factors have been confirmed to be associated with the pathogenesis and prognosis of IS. In this study we conducted a meta-analysis on studies concerning Interleukin 6 (IL-6), NOS3, PON and SERPINE1 polymorphisms and IS susceptibility. Methods: PubMed, Medline, and Embase databases were searched for relevant articles. The pooled odds ratios (ORs) with their corresponding 95% confidence intervals (95% CIs) under five genetic models were calculated to evaluated the relations between 4 candidate genes and the risk of IS. The heterogeneity among studies was assessed by chi-square test and the statistic of I-2. Subgroup analyses were performed based on ethnicity and all statistical tests were conducted by R 3.1.2 software. Result: A total of 149 published studies were selected, which consisted of 33,758 IS cases and 56,298 control subjects. For NOS3 gene, rs1799983 and rs61722009 increased the susceptibility to IS while rs662 of PON1 gene and rs12026 of PON2 gene decreased the risk of IS. No significant association was detected between rs7493 of PON2, rs854560 of PON1 and IS risk. Conclusion: This meta-analysis demonstrated that the NOS3 gene rs1799983 and rs61722009 polymorphisms, the PON1 gene rs662 polymorphism, and the PON2 gene rs12026 polymorphism might be associated with ischemic stroke overall.