title: IL1RN VNTR polymorphism in ischemic stroke: analysis in 3 populations.
abstract: OBJECTIVE
  Genetic factors influence risk for ischemic stroke and likely do so at multiple steps in the pathogenic process. Variants in genes related to inflammation contribute to risk of stroke. The purpose of this study was to confirm our earlier finding of an association between allele 2 of a variable number tandem repeat of the IL-1 receptor antagonist gene (IL1RN) and cerebrovascular disease.
  
  
  METHODS
  An association study of the variable number tandem repeat genotype with ischemic stroke and stroke subtypes was performed on samples from a North American study of affected sibling pairs concordant for ischemic stroke and 2 North American cohorts of prospectively ascertained ischemic stroke cases and unrelated controls. DNA analysis was performed on cases and controls, stratified by race.
  
  
  RESULTS
  After adjustment for age, sex, and stroke risk factors, the odds ratio for association of allele 2 and ischemic stroke was 2.80 (95% confidence interval, 1.29 to 6.11; P=0.03) for the white participants. The effect of allele 2 of IL1RN on stroke risk most closely fits a recessive genetic model (P=0.009). For the smaller sample of nonwhite participants, the results were not significant.
  
  
  CONCLUSIONS
  Allele 2 of IL1RN, present in nearly one-quarter of stroke patients, may contribute to genetic risk for ischemic stroke and confirm the previously identified association with cerebrovascular disease. These results are driven by the association in the white participants. Further exploration in a larger nonwhite sample is warranted.
authors.affiliation: Department of Neurology, University of Virginia Health System, Charlottesville, VA, USA.
authors.forename: Bradford B
authors.initials: BB
authors.lastname: Worrall
authors.forename: Thomas G
authors.initials: TG
authors.lastname: Brott
authors.forename: Robert D
authors.initials: RD
authors.lastname: Brown
authors.forename: W Mark
authors.initials: WM
authors.lastname: Brown
authors.forename: Stephen S
authors.initials: SS
authors.lastname: Rich
authors.forename: Sampath
authors.initials: S
authors.lastname: Arepalli
authors.forename: Fabienne
authors.initials: F
authors.lastname: Wavrant-De Vrièze
authors.forename: Jaime
authors.initials: J
authors.lastname: Duckworth
authors.forename: Andrew B
authors.initials: AB
authors.lastname: Singleton
authors.forename: John
authors.initials: J
authors.lastname: Hardy
authors.forename: James F
authors.initials: JF
authors.lastname: Meschia
mesh_terms: D000368:Aged; D002545:Brain Ischemia / Q000235:genetics* / Q000276:immunology / Q000503:physiopathology; D015331:Cohort Studies; D004252:DNA Mutational Analysis; D005260:Female; D005787:Gene Frequency / Q000235:genetics; D020022:Genetic Predisposition to Disease / Q000235:genetics*; D005820:Genetic Testing; D006801:Humans; D007249:Inflammation / Q000235:genetics / Q000378:metabolism / Q000503:physiopathology; D053590:Interleukin 1 Receptor Antagonist Protein / Q000235:genetics*; D008297:Male; D008875:Middle Aged; D018598:Minisatellite Repeats / Q000235:genetics*; D009656:North America; D011110:Polymorphism, Genetic / Q000235:genetics*; D035781:Siblings; D020521:Stroke / Q000235:genetics* / Q000276:immunology / Q000503:physiopathology; D044465:White People
chemical_list: C507763:IL1RN protein, human; D053590:Interleukin 1 Receptor Antagonist Protein