title: Estrogen receptor α gene polymorphisms and risk of Alzheimer's disease: evidence from a meta-analysis.
abstract: OBJECTIVE
  Human estrogen receptor α (ESR1), a member of the nuclear receptor superfamily of ligand-activated transcription factors, is one of the key mediators of hormonal response in estrogen-sensitive tissues. Accumulating evidence has demonstrated that two of the most widely studied single-nucleotide polymorphisms in ESR1 - PvuII (T/C, rs223493) and Xbal (A/G, rs9340799) - are possibly associated with Alzheimer's disease (AD). However, individual study results are still controversial.
  
  
  METHODS
  We searched PubMed, Embase, Web of Science, Science Direct, SpringerLink, and the Chinese National Knowledge Infrastructure databases for eligible studies assessing the association of ESR1 polymorphisms and AD risk (last search performed in November 2013). Thereafter, a meta-analysis of 13,192 subjects from 18 individual studies was conducted to evaluate the association between ESR1 polymorphisms and susceptibility to AD.
  
  
  RESULTS
  The results indicated that a significant association was found between the ESR1 PvuII polymorphism and AD risk in Caucasian populations (CC + CT versus TT, odds ratio [OR] 1.14, 95% confidence interval [CI] 1.02-1.28, P=0.03; CT versus TT, OR 1.16, 95% CI 1.02-1.31, P=0.02), whereas no evidence of association was found in Asian populations. Nevertheless, we did not find any significant association between the ESR1 XbaI polymorphism and AD risk for any model in Caucasian and Asian populations (all P>0.05).
  
  
  CONCLUSIONS
  Based on this meta-analysis, we conclude that the ESR1 PvuII polymorphism might be a risk factor in AD development in Caucasian populations, not in Asian populations. Further confirmation is needed from better-designed and larger studies.
authors: Department of Transfusion, First Hospital of China Medical University, Shenyang, People's Republic of China.
authors: Daye
authors: D
authors: Cheng
authors: Department of Clinical Laboratory, High Vocational Technological College, China Medical University, Shenyang, People's Republic of China.
authors: Bin
authors: B
authors: Liang
authors: Department of Transfusion, First Hospital of China Medical University, Shenyang, People's Republic of China.
authors: Yiwen
authors: Y
authors: Hao
authors: Department of Transfusion, First Hospital of China Medical University, Shenyang, People's Republic of China.
authors: Wenling
authors: W
authors: Zhou
mesh_terms: D000368:Aged; D000544:Alzheimer Disease / Q000453:epidemiology* / Q000235:genetics*; D044466:Asian People / Q000235:genetics / Q000706:statistics & numerical data; D047628:Estrogen Receptor alpha / Q000235:genetics*; D020022:Genetic Predisposition to Disease / Q000453:epidemiology* / Q000235:genetics*; D006801:Humans; D020641:Polymorphism, Single Nucleotide; D012307:Risk Factors; D044465:White People / Q000235:genetics / Q000706:statistics & numerical data
chemical_list: C506487:ESR1 protein, human; D047628:Estrogen Receptor alpha
keywords: Alzheimer’s disease; estrogen receptor; meta-analysis; polymorphism