title: Polymorphisms of the matrix metalloproteinase 9 gene and abdominal aortic aneurysm.
abstract: BACKGROUND
  Increased matrix metalloproteinase (MMP) 9 activity has been implicated in the formation of abdominal aortic aneurysm (AAA). The aim was to explore the association between potentially functional variants of the MMP-9 gene and AAA.
  
  
  METHODS
  The -1562C > T and -1811A > T variants of the MMP-9 gene were genotyped in 678 men with an AAA (at least 30 mm in diameter) and 659 control subjects (aortic diameter 19-22 mm) recruited from a population-based trial of screening for AAA. Levels of MMP-9 were measured in a random subset of 300 cases and 84 controls. The association between genetic variants (including haplotypes) and AAA was assessed by multivariable logistic regression.
  
  
  RESULTS
  There was no association between the MMP-9-1562C > T (odds ratio (OR) 0.70 (95 per cent confidence interval (c.i.) 0.27 to 1.82)) or -1811A > T (OR 0.71 (95 per cent c.i. 0.28 to 1.85)) genotypes, or the most common haplotype (OR 0.81 (95 per cent c.i. 0.62 to 1.05)) and AAA. The serum MMP-9 concentration was higher in cases than controls, and in minor allele carriers in cases and controls, although the differences were not statistically significant.
  
  
  CONCLUSIONS
  In this study, the genetic tendency to higher levels of circulating MMP-9 was not associated with AAA.
authors.affiliation: Schools of Surgery, University of Western Australia, Fremantle, Western Australia.
authors.forename: L
authors.initials: L
authors.lastname: Smallwood
authors.forename: R
authors.initials: R
authors.lastname: Allcock
authors.forename: F
authors.initials: F
authors.lastname: van Bockxmeer
authors.forename: N
authors.initials: N
authors.lastname: Warrington
authors.forename: L J
authors.initials: LJ
authors.lastname: Palmer
authors.forename: B
authors.initials: B
authors.lastname: Iacopetta
authors.forename: J
authors.initials: J
authors.lastname: Golledge
authors.forename: P E
authors.initials: PE
authors.lastname: Norman