title: Endemic fluorosis in Henan province, China: ERα gene polymorphisms and reproductive hormones among women.
abstract: OBJECTIVE
  The aim of this study was to explore the influence of fluoride exposure and ERα gene polymorphisms on reproductive hormone concentrations of women in accordance with endemic fluorosis residence.
  
  
  METHODS
  A cross sectional study was conducted in Tongxu county, Henan Province, China. A total of 679 women were recruited using cluster sampling and each subject provided fasting blood and an associated urine sample. We measured the concentrations of serum gonadotropin releasing hormone (GnRH), follicle-stimulating hormone, luteinizing hormone, and estradiol and urinary fluoride.
  
  
  RESULTS
  In the defluoridation project group (DFPG), serum GnRH was lower in women carrying C/C genotype compared to in those carrying C/T and T/T genotypes of ERα gene rs3798577 (p<0.05). In the endemic fluorosis group (EFG), serum GnRH was lower in women carrying Pp genotype compared to in those carrying PP and pp genotypes of ERα PvuII (p<0.05). Serum GnRH in women from EFG who carried Pp, pp, Xx and xx genotypes in ERα gene PvuII and XbaI was lower than in those in the control group (CG) who carried same genotypes (p<0.05). Furthermore, serum GnRH in women from EFG was significantly lower than in those in CG, regardless of whether the women were carrying C/C, C/T or T/T genotypes of ERα rs3798577 (p<0.05). Serum estradiol concentrations in EFG were significantly lower than in CG when the women were carrying the Pp, Xx and T/T genotypes in ERα gene (p<0.05).
  
  
  CONCLUSIONS
  Interaction of ERα gene and fluoride exposure may influence women's serum reproductive hormone concentrations.
authors.affiliation: School of Public Health, Zhengzhou University, Zhengzhou, Henan, China.
authors.forename: Guo-Yu
authors.initials: GY
authors.lastname: Zhou
authors.affiliation: Kaifeng Center for Disease Prevention and Control, Kaifeng, Henan, China.
authors.forename: Li-Jun
authors.initials: LJ
authors.lastname: Ren
authors.affiliation: Suizhou Center for Disease Control and Prevention, Suizhou, Hubei, China.
authors.forename: Jia-Xiang
authors.initials: JX
authors.lastname: Hou
authors.affiliation: School of Public Health, Zhengzhou University, Zhengzhou, Henan, China.
authors.forename: Liu-Xin
authors.initials: LX
authors.lastname: Cui
authors.affiliation: Kaifeng Center for Disease Prevention and Control, Kaifeng, Henan, China.
authors.forename: Zhong
authors.initials: Z
authors.lastname: Ding
authors.affiliation: School of Public Health, Zhengzhou University, Zhengzhou, Henan, China.
authors.forename: Xue-Min
authors.initials: XM
authors.lastname: Cheng
authors.affiliation: School of Public Health, Zhengzhou University, Zhengzhou, Henan, China.
authors.forename: Jing-Yuan
authors.initials: JY
authors.lastname: Zhu
authors.affiliation: School of Public Health, Zhengzhou University, Zhengzhou, Henan, China.
authors.forename: Rui-Rui
authors.initials: RR
authors.lastname: Cui
authors.affiliation: School of Public Health, Zhengzhou University, Zhengzhou, Henan, China. Email: byyue@zzu.edu.cn.
authors.forename: Yue
authors.initials: Y
authors.lastname: Ba
mesh_terms: D000293:Adolescent; D000328:Adult; D002681:China / Q000453:epidemiology; D003430:Cross-Sectional Studies; D019353:Endemic Diseases; D004781:Environmental Exposure; D004958:Estradiol / Q000097:blood; D047628:Estrogen Receptor alpha / Q000235:genetics*; D005260:Female; D005458:Fluoride Poisoning / Q000453:epidemiology* / Q000235:genetics*; D005459:Fluorides / Q000009:adverse effects* / Q000652:urine; D009050:Fluorosis, Dental; D005640:Follicle Stimulating Hormone / Q000097:blood; D005838:Genotype; D007987:Gonadotropin-Releasing Hormone / Q000097:blood; D006728:Hormones / Q000097:blood*; D006801:Humans; D007986:Luteinizing Hormone; D008875:Middle Aged; D011110:Polymorphism, Genetic; D055815:Young Adult
chemical_list: C506487:ESR1 protein, human; D047628:Estrogen Receptor alpha; D006728:Hormones; D007987:Gonadotropin-Releasing Hormone; D004958:Estradiol; D007986:Luteinizing Hormone; D005640:Follicle Stimulating Hormone; D005459:Fluorides