title: A Meta-Analysis of the Association between ESR1 Genetic Variants and the Risk of Breast Cancer.
abstract: BACKGROUND
  Single nucleotide polymorphisms (SNPs) in the estrogen receptor gene (ESR1) play critical roles in breast cancer (BC) susceptibility. Genome-wide association studies have reported that SNPs in ESR1 are associated with BC susceptibility; however, the results of recent studies have been inconsistent. Therefore, we performed this meta-analysis to obtain more accurate and credible results.
  
  
  METHODS
  We pooled published literature from PubMed, EMBASE, and Web of Science and calculated odds ratios (ORs) with 95% confidence intervals (CIs) to assess the strength of associations using fixed effects models and random effects models. Twenty relevant case-control and cohort studies of the 3 related SNPs were identified.
  
  
  RESULTS
  Three SNPs of the ESR1 gene, rs2077647:T>C, rs2228480:G>A and rs3798577:T>C, were not associated with increased BC risk in our overall meta-analysis. Stratified analysis by ethnicity showed that in Caucasians, the rs2228480 AA genotype was associated with a 26% decreased risk of BC compared with the GG genotype (OR = 0.740, 95% CI: 0.555-0.987). The C allele of the rs3798577:T>C variant was associated with decreased BC risk in Asians (OR = 0.828, 95% CI: 0.730-0.939), while Caucasians with this allele were found to experience significantly increased BC risk (OR = 1.551, 95% CI: 1.037-2.321). A non-significant association between rs2077647 and BC risk was identified in all of the evaluated ethnic populations.
  
  
  CONCLUSIONS
  Rs3798577 was associated with an increased risk of BC in Caucasian populations but a decreased risk in Asians. Rs2228480 had a large protective effect in Caucasians, while rs2077647 was not associated with BC risk.
authors.affiliation: Department of Epidemiology and Biostatistics, School of Public Health, Southeast University, Nanjing, China.
authors.forename: Taishun
authors.initials: T
authors.lastname: Li
authors.affiliation: National Research Institute for Family Planning, Beijing, China.
authors.forename: Jun
authors.initials: J
authors.lastname: Zhao
authors.affiliation: Department of Epidemiology and Biostatistics, School of Public Health, Southeast University, Nanjing, China.
authors.forename: Jiaying
authors.initials: J
authors.lastname: Yang
authors.affiliation: National Research Institute for Family Planning, Beijing, China.
authors.forename: Xu
authors.initials: X
authors.lastname: Ma
authors.affiliation: National Research Institute for Family Planning, Beijing, China.
authors.forename: Qiaoyun
authors.initials: Q
authors.lastname: Dai
authors.affiliation: Department of Epidemiology and Biostatistics, School of Public Health, Southeast University, Nanjing, China.
authors.forename: Hao
authors.initials: H
authors.lastname: Huang
authors.affiliation: Department of Epidemiology and Biostatistics, School of Public Health, Southeast University, Nanjing, China.
authors.forename: Lina
authors.initials: L
authors.lastname: Wang
authors.affiliation: National Research Institute for Family Planning, Beijing, China.
authors.forename: Pei
authors.initials: P
authors.lastname: Liu
mesh_terms: D000483:Alleles; D044466:Asian People / Q000235:genetics; D001943:Breast Neoplasms / Q000235:genetics*; D016022:Case-Control Studies; D015331:Cohort Studies; D047628:Estrogen Receptor alpha / Q000235:genetics*; D005260:Female; D020022:Genetic Predisposition to Disease / Q000235:genetics*; D014644:Genetic Variation / Q000235:genetics*; D055106:Genome-Wide Association Study / Q000379:methods; D005838:Genotype; D006801:Humans; D020641:Polymorphism, Single Nucleotide / Q000235:genetics*; D012307:Risk Factors; D044465:White People / Q000235:genetics
chemical_list: C506487:ESR1 protein, human; D047628:Estrogen Receptor alpha