title: Androgen receptor CAG repeat length correlates with semen PSA levels in adolescence.
abstract: BACKGROUND
  Androgens exert their action through the androgen receptor (AR). The length of the AR CAG repeat is inversely correlated to receptor function and short CAG length might be a risk factor for development of prostate cancer. Our aim was to investigate whether CAG repeat number might have an impact on prostate function in adolescence.
  
  
  METHODS
  AR genotyping was performed by direct sequencing of leukocyte DNA from 274 military conscripts. All men underwent endocrine evaluation and semen analysis.
  
  
  RESULTS
  PSA in seminal plasma, total sperm count and motility all are inversely correlated with CAG numbers (rho = -0.128, P = 0.038; rho = -0.156, P = 0.010; rho = -0.158, P = 0.011), whereas serum levels of free testosterone (rho = 0.132; P = 0.029) and luteinizing hormone (rho = 0.126; P = 0.037) are positively correlated to CAG length. No correlation between seminal PSA and serum testosterone, neither free nor total, was found.
  
  
  CONCLUSIONS
  In adolescence, AR genotype, but not serum testosterone, is associated with the level of seminal PSA.
authors.affiliation: Department of Urology, Malmö University Hospital, Lund University, Malmö, Sweden. Yvonne.Giwercman@kir.mas.lu.se
authors.forename: Yvonne Lundberg
authors.initials: YL
authors.lastname: Giwercman
authors.forename: Jonas
authors.initials: J
authors.lastname: Richthoff
authors.forename: Hans
authors.initials: H
authors.lastname: Lilja
authors.forename: Camilla
authors.initials: C
authors.lastname: Anderberg
authors.forename: Per-Anders
authors.initials: PA
authors.lastname: Abrahamsson
authors.forename: Aleksander
authors.initials: A
authors.lastname: Giwercman
mesh_terms: D000293:Adolescent / Q000502:physiology*; D000328:Adult; D005838:Genotype; D006801:Humans; D007986:Luteinizing Hormone / Q000097:blood; D008297:Male; D017430:Prostate-Specific Antigen / Q000032:analysis*; D011471:Prostatic Neoplasms / Q000235:genetics* / Q000503:physiopathology*; D011944:Receptors, Androgen / Q000235:genetics*; D012307:Risk Factors; D012661:Semen / Q000737:chemistry; D017422:Sequence Analysis, DNA; D013739:Testosterone / Q000097:blood; D019680:Trinucleotide Repeat Expansion / Q000235:genetics*
chemical_list: D011944:Receptors, Androgen; D013739:Testosterone; D007986:Luteinizing Hormone; D017430:Prostate-Specific Antigen