title: The role of TNF-α 308G>A polymorphism in the risk for ischemic stroke.
abstract: BACKGROUND
  Stroke is a common health problem; however, its pathogenesis is not clear. Several studies have examined the association of -308G>A promoter polymorphism in the tumor necrosis factor-α gene (TNF-α) with ischemic stroke susceptibility. However, the results of these studies are inconsistent and the sample sizes of most of the studies were small. Thus, a meta-analysis was conducted to provide a more robust estimate of the effect of the TNF-α 308G>A polymorphism on the risk for ischemic stroke.
  
  
  METHODS
  Odds ratios with 95% confidence intervals were used to assess the strength of the association of TNF-α polymorphisms with ischemic stroke. Cochran's Q statistic and the inconsistency index (I) were used to explore heterogeneity. Egger's test and inverted funnel plots were used to investigate publication bias.
  
  
  RESULTS
  Thirteen studies met the inclusion criteria involving 3515 cases and 3949 controls. A significant association was found between TNF-α 308G>A polymorphism and the development of ischemic stroke in the Asian population. However, no statistically significant association was observed in the overall analysis and in the Caucasian population. In the subgroup analysis by age, a significant association was found in the juvenile and adult populations, showing that TNF-α 308G>A polymorphism is associated with the risk for juvenile ischemic stroke.
  
  
  CONCLUSIONS
  This study suggests that TNF-α 308G>A polymorphism is associated with the risk for juvenile ischemic stroke, whereas it is a protective factor for ischemic stroke in Asians and the adult population. However, in the overall analysis and in Caucasians, a significant association was not found.
authors.affiliation: Department of Internal Neurology, Guangxi Traditional Chinese Medicine University, Nanning, China.
authors.forename: Lian
authors.initials: L
authors.lastname: Gu
authors.forename: Guangliang
authors.initials: G
authors.lastname: Wu
authors.forename: Jianxiong
authors.initials: J
authors.lastname: Long
authors.forename: Li
authors.initials: L
authors.lastname: Su
authors.forename: Yan
authors.initials: Y
authors.lastname: Yan
authors.forename: Qing
authors.initials: Q
authors.lastname: Chen
authors.forename: Juanjuan
authors.initials: J
authors.lastname: Xie
authors.forename: Yanling
authors.initials: Y
authors.lastname: Hu
mesh_terms: D000367:Age Factors; D044466:Asian People; D002545:Brain Ischemia / Q000235:genetics*; D005260:Female; D020022:Genetic Predisposition to Disease; D006801:Humans; D008297:Male; D020641:Polymorphism, Single Nucleotide; D012307:Risk Factors; D020521:Stroke / Q000235:genetics*; D014409:Tumor Necrosis Factor-alpha / Q000235:genetics*
chemical_list: D014409:Tumor Necrosis Factor-alpha