title: CAG repeat within the androgen receptor gene and incidence of surgery for benign prostatic hyperplasia in U.S. physicians.
abstract: BACKGROUND
  CAG repeat length in exon 1 of the androgen receptor (AR) gene correlates inversely with transcriptional transactivation activity of the AR. Men with shorter AR CAG repeat lengths are at higher risk of prostate cancer. Because benign prostatic hyperplasia (BPH) is an androgen-dependent condition, we examined the hypothesis that a shorter AR gene CAG repeat length increases the risk of developing of BPH.
  
  
  METHODS
  Among 14,916 men of the Physicians' Health Study who had provided a blood sample in 1982, we measured AR gene CAG repeat lengths for 310 men who had surgery for BPH up to 7.5 years of follow-up and 1,041 controls.
  
  
  RESULTS
  Risk of surgery for BPH increased linearly with decreasing AR CAG repeat length (P (trend) = 0.03). Relative to men with a CAG repeat length > or = 25, men with a repeat length < or = 19 had an odds ratio of BPH surgery of 1.76 (95% confidence interval, 1.16-2.65).
  
  
  CONCLUSIONS
  Variability in the AR gene CAG repeat influences the development of symptomatic BPH.
authors.affiliation: Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts, USA. edward.giovannucci@channing.harvard.edu
authors.forename: E
authors.initials: E
authors.lastname: Giovannucci
authors.forename: M J
authors.initials: MJ
authors.lastname: Stampfer
authors.forename: A
authors.initials: A
authors.lastname: Chan
authors.forename: K
authors.initials: K
authors.lastname: Krithivas
authors.forename: P H
authors.initials: PH
authors.lastname: Gann
authors.forename: C H
authors.initials: CH
authors.lastname: Hennekens
authors.forename: P W
authors.initials: PW
authors.lastname: Kantoff
mesh_terms: D006801:Humans; D008297:Male; D010820:Physicians; D011470:Prostatic Hyperplasia / Q000235:genetics* / Q000601:surgery; D011944:Receptors, Androgen / Q000235:genetics*; D018911:Trinucleotide Repeats / Q000235:genetics*; D014481:United States; D013521:Urologic Surgical Procedures, Male / Q000706:statistics & numerical data
chemical_list: D011944:Receptors, Androgen