Genetic polymorphism of β-fibrinogen gene-455G/A can contribute to the risk of ischemic stroke

Many studies have investigated the association between the beta-fibrinogen gene-455G/A (FG beta-455G/A) polymorphism and the risk of ischemic stroke. However, these evidences were inadequate to provide stronger conclusions because most studies were generally small. To shed light on these inconclusive findings, we conducted a large sample size meta-analysis of studies relating to the FG beta-455G/A polymorphism and the risk of ischemic stroke. Odds ratios with a 95 % confidence interval were used to investigate the association between FG beta-455G/A polymorphism and ischemic stroke. Publication bias was tested by Egger's test and funnel plot. Inconsistency index and Cochran's Q statistic were used to check heterogeneity. Cumulative and recursive cumulative meta-analyses were performed to provide a framework for updating a genetic effect from all of the included studies. Twenty-six independent publications with 4,070 cases and 4,649 controls were included in this meta-analysis. Results showed that the beta-fibrinogen-455G/A polymorphism was significantly associated with the risk of ischemic stroke. The FG beta-455G/A polymorphism was found to be a risk factor for ischemic stroke in Asians and adults, while association was not observed for Caucasians and juveniles based on the small size and it may be necessary to conduct larger studies on them to investigate the association in the future. The cumulative meta-analysis indicated a decline from 1998 to 2003, and the results remained stable during the period 2004-2012. The results indicate that FG beta-455G/A polymorphism may be a susceptible predictor of ischemic stroke. More studies are needed to elucidate the relationship further.