title: Transforming growth factor beta receptor I polyalanine repeat polymorphism does not increase ovarian cancer risk.
abstract: OBJECTIVE
  It has been suggested that the 6A allele of the type I TGFbeta receptor (TGFbetaR1) polyalanine repeat tract polymorphism may increase susceptibility to various types of cancer including ovarian cancer.
  
  
  METHODS
  The TGFbetaR1 polyalanine polymorphism was genotyped in 588 ovarian cancer cases and 614 controls from a population-based case-control study in North Carolina.
  
  
  RESULTS
  Significant racial differences in the frequency of the 6A allele were observed between Caucasian (10.7%) and African-American (2.4%) controls (P < 0.001). One or two copies of the 6A allele of the TGFbetaR1 polyalanine polymorphism was carried by 18% of all controls and 19% of cases, and there was no association with ovarian cancer risk (OR = 1.07, 95% CI 0.80-1.44). The odds ratio for 6A homozygotes was 1.81 (95% CI 0.655.06), but these comprised only 0.98% of controls and 1.70% of cases.
  
  
  CONCLUSIONS
  The 6A allele of the TGFbetaR1 polyalanine polymorphism does not appear to increase ovarian cancer risk. Larger studies would be needed to exclude the possibility that the small fraction of individuals who are 6A homozygotes have an increased risk of ovarian or other cancers.
authors.affiliation: Department of Obstetrics and Gynecology, Division of Gynecologic Oncology, Duke University, DUMC Box 3079, Durham, NC 27710, USA.
authors.forename: Monique A
authors.initials: MA
authors.lastname: Spillman
authors.forename: Joellen M
authors.initials: JM
authors.lastname: Schildkraut
authors.forename: Susan
authors.initials: S
authors.lastname: Halabi
authors.forename: Patricia
authors.initials: P
authors.lastname: Moorman
authors.forename: Brian
authors.initials: B
authors.lastname: Calingaert
authors.forename: Rex C
authors.initials: RC
authors.lastname: Bentley
authors.forename: Jeffrey R
authors.initials: JR
authors.lastname: Marks
authors.forename: Susan
authors.initials: S
authors.lastname: Murphy
authors.forename: Andrew
authors.initials: A
authors.lastname: Berchuck
mesh_terms: D000328:Adult; D000368:Aged; D000483:Alleles; D016022:Case-Control Studies; D005260:Female; D020022:Genetic Predisposition to Disease; D006801:Humans; D008875:Middle Aged; D009657:North Carolina / Q000453:epidemiology; D010051:Ovarian Neoplasms / Q000453:epidemiology / Q000235:genetics*; D010455:Peptides / Q000235:genetics; D011110:Polymorphism, Genetic; D018125:Receptors, Transforming Growth Factor beta / Q000235:genetics*; D020449:Repetitive Sequences, Amino Acid
chemical_list: D010455:Peptides; D018125:Receptors, Transforming Growth Factor beta; C019529:polyalanine