title: Polymorphisms in estrogen receptors predict the risk of male infertility: a meta-analysis.
abstract: BACKGROUND
  Estrogen receptors play an important role in mediating estrogen action on target tissues, and the estrogen is relevant to male infertility. Single nucleotide polymorphisms (SNPs) in estrogen receptors may be associated with the risk of male infertility. A variety of case control studies have been published evaluating this association. However, the accumulated studies have shown inconsistent conclusions.
  
  
  METHODS
  To further determine the potential association between the four common SNPs (rs2234693, rs9340799, rs1256049 and rs4986938) in estrogen receptors gene and male infertility, this meta-analysis was performed according to the 10 published case control studies. The odds ratio (OR) and 95% confidence interval (CI) were used to evaluate the strength of the associations.
  
  
  RESULTS
  It was revealed that the sub-group analysis by the ethnicity, for the rs2234693, a significant association in the comparison of CC vs. TT (OR = 0.61, 95% CI: 0.40-0.93), CT vs. TT (OR = 0.67, 95% CI: 0.49-0.93) and CC + CT vs. TT (OR = 0.66, 95% CI: 0.49-0.89) in the Asian population with male infertility. For rs9340799 polymorphism, increased risks were observed for the comparison of AA vs. GG (OR = 1.75, 95% CI: 1.15-2.68) and AA vs. GA + GG (OR = 1.38, 95% CI: 1.02-1.88). For rs1256049 polymorphism, the comparison of the GA vs. GG (OR = 1.52, 95% CI: 1.00-2.31) and AA + GA vs. GG (OR = 1.74, 95% CI: 1.03-2.94), also increased risks present in Asian and Caucasian population, respectively.
  
  
  CONCLUSIONS
  The rs2234693C allele was associated with the decreased risk for male infertility; however, the rs9340799AA genotype and the rs1256049GA genotype were associated with an increased risk for male infertility.
authors.forename: Tian-Fu
authors.initials: TF
authors.lastname: Li
authors.forename: Qiu-Yue
authors.initials: QY
authors.lastname: Wu
authors.forename: Cui
authors.initials: C
authors.lastname: Zhang
authors.forename: Wei-Wei
authors.initials: WW
authors.lastname: Li
authors.forename: Na
authors.initials: N
authors.lastname: Li
authors.forename: Ying-Xia
authors.initials: YX
authors.lastname: Cui
authors.forename: Xiao-Jun
authors.initials: XJ
authors.lastname: Li
authors.affiliation: Department of Reproduction and Genetics, Institute of Laboratory Medicine, Jinling Hospital, Nanjing University School of Medicine, Nanjing 210002, PR China. xinyixia78@gmail.com.
authors.forename: Xin-Yi
authors.initials: XY
authors.lastname: Xia
mesh_terms: D016022:Case-Control Studies; D047628:Estrogen Receptor alpha / Q000235:genetics* / Q000378:metabolism; D047629:Estrogen Receptor beta / Q000235:genetics* / Q000378:metabolism; D056726:Genetic Association Studies; D020022:Genetic Predisposition to Disease; D006801:Humans; D007248:Infertility, Male / Q000235:genetics* / Q000378:metabolism; D008297:Male; D020641:Polymorphism, Single Nucleotide
chemical_list: C506487:ESR1 protein, human; D047628:Estrogen Receptor alpha; D047629:Estrogen Receptor beta; C479998:estrogen receptor beta isoform M, human