title: Estrogen receptor alpha dinucleotide repeat and cytochrome P450c17alpha gene polymorphisms are associated with susceptibility to endometriosis.
abstract: OBJECTIVE
  To investigate the association of endometriosis with estrogen receptor alpha (ER alpha) and cytochrome P450c17alpha (CYP17) gene polymorphisms in light of the fact that estrogen plays a role in the pathogenesis of endometriosis and the CYP17 enzyme is involved with estrogen biosynthesis.
  
  
  METHODS
  Prospective study.
  
  
  METHODS
  Genetics and gynecology units.
  
  
  METHODS
  All patients were divided into two groups: group 1, women with endometriosis (n = 119); group 2, normal controls (n = 108).
  
  
  METHODS
  A dinucleotide (thymine-adenine [TA]) repeat polymorphism lying upstream of the ER alpha gene and A1/A2 polymorphism of the CYP17 gene were amplified by polymerase chain reaction, enzyme restriction, and electrophoresis.
  
  
  METHODS
  The ER genotypes were classified into A through T (TA repeats, 10-29). The CYP17 genotypes included indigestible (A1 homozygote), heterozygote, and digestible (A2 homozygote). We compared these polymorphism distributions in both groups.
  
  
  RESULTS
  The percentage of genotypes D-G (TA, 13-16) in both groups were 10.5%, 29.4%, 13.0%, and 11.3% in group 1 and 7.9%, 16.7%, 19.9%, and 17.6% in group 2. The genotype E (14 TA repeats) is associated with a higher risk of endometriosis. Proportions of A1 homozygote/heterozygote/A2 homozygote for CYP17 were 26.1%/46.2%/27.7% for group 1 and 14.8%/44.5%/40.7% for group 2, respectively. The A1 homozygote and allele were associated with a higher susceptibility of endometriosis.
  
  
  CONCLUSIONS
  ER alpha* 14 TA repeats and the CYP17* A1 allele are associated with an increased risk of endometriosis. Both polymorphisms are useful markers for predicting endometriosis susceptibility.
authors.affiliation: Department of Obstetrics and Gynecology, China Medical University Hospital, Taichung, Taiwan.
authors.forename: Yao-Yuan
authors.initials: YY
authors.lastname: Hsieh
authors.forename: Chi-Chen
authors.initials: CC
authors.lastname: Chang
authors.forename: Fuu-Jen
authors.initials: FJ
authors.lastname: Tsai
authors.forename: Cheng-Chieh
authors.initials: CC
authors.lastname: Lin
authors.forename: Chang-Hai
authors.initials: CH
authors.lastname: Tsai
mesh_terms: D018900:Dinucleotide Repeats; D004715:Endometriosis / Q000453:epidemiology* / Q000235:genetics*; D047628:Estrogen Receptor alpha / Q000235:genetics*; D005260:Female; D020022:Genetic Predisposition to Disease / Q000453:epidemiology; D005838:Genotype; D006579:Heterozygote; D006720:Homozygote; D006801:Humans; D020641:Polymorphism, Single Nucleotide; D012307:Risk Factors; D013254:Steroid 17-alpha-Hydroxylase / Q000235:genetics*
chemical_list: D047628:Estrogen Receptor alpha; D013254:Steroid 17-alpha-Hydroxylase