title: Effects of tumor necrosis factor-β (TNF-β) 252A>G polymorphism on the development of migraine: a meta-analysis.
abstract: OBJECTIVE
  Genetic factors including TNF-β have been considered as important components in the aetiology of migraine. Many studies have investigated the association between TNF-β 252A>G polymorphism and migraine risk, with debatable results. This study was designed to examine whether the TNF-β 252A>G polymorphism confers genetic susceptibility to migraine in diverse populations.
  
  
  METHODS
  Studies eligible for this meta-analysis were searched in the PubMed, Embase, and CNKI by using the keywords "tumor necrosis factor", "TNF", "252A>G", "rs909253", "polymorphism", "polymorphisms", "variant", "SNP", combined with "migraine" or "migraine with aura (MA)" or "migraine without aura (MO)". Pooled ORs and 95% CI were appropriately calculated using the fixed-effect model.
  
  
  RESULTS
  We finally included a total of seven studies, providing 5 557 migraineurs and 20 543 unrelated healthy controls. Meta-analysis results showed no statistical evidence of a significant association between TNF-β 252A>G polymorphism and overall migraine risk. Stratified analyses by type of migraine and gender revealed similar results. Interestingly, an OR with 95% CI representing an increased migraine risk was indicated in Asians under the recessive model (GG vs. AG + AA: OR, 1.38; 95%CI, 1.04-1.84; P for heterogeneity, 0.665).
  
  
  CONCLUSIONS
  Our findings appear to support the hypothesis that genetic variability of 252A>G polymorphism in TNF region may modulate risk of migraine in the population of Asian ancestry.
authors: Department of Neurology, Chinese PLA General Hospital, Beijing, China.
authors: Ruozhuo
authors: R
authors: Liu
authors: Ministry of Resource Construction, Medical Library of the Chinese PLA, Academy of Military Medical Sciences, Beijing, China.
authors: Minghui
authors: M
authors: Ma
authors: Department of Neurology, Chinese PLA General Hospital, Beijing, China.
authors: Mingyu
authors: M
authors: Cui
authors: Department of Neurology, Chinese PLA General Hospital, Beijing, China.
authors: Zhao
authors: Z
authors: Dong
authors: Department of Neurology, Chinese PLA General Hospital, Beijing, China.
authors: Xiaolin
authors: X
authors: Wang
authors: Department of Neurology, Chinese PLA General Hospital, Beijing, China.
authors: Wei
authors: W
authors: Zhang
authors: Department of Traditional Chinese Medicine, Chinese PLA General Hospital, Beijing, China.
authors: Minghui
authors: M
authors: Yang
authors: Department of Neurology, Chinese PLA General Hospital, Beijing, China.
authors: Shengyuan
authors: S
authors: Yu
mesh_terms: D000483:Alleles; D020022:Genetic Predisposition to Disease; D005838:Genotype; D006801:Humans; D008233:Lymphotoxin-alpha / Q000235:genetics*; D008881:Migraine Disorders / Q000235:genetics*; D016017:Odds Ratio; D020641:Polymorphism, Single Nucleotide; D017594:Publication Bias
chemical_list: D008233:Lymphotoxin-alpha