title: Novel mutations in leukotriene C4 synthase and risk of cardiovascular disease based on genotypes from 50,000 individuals.
abstract: BACKGROUND
  Atherosclerosis is an inflammatory condition where cysteinyl leukotrienes have been identified to play an important role. Furthermore, cysteinyl leukotrienes may also affect thrombus formation. Using prospective, cross-sectional and case-control designs, we tested the hypothesis that hitherto unknown genetic variation, likely to affect the function of leukotriene C(4) synthase, is associated with risk of venous thromboembolism, ischemic stroke and myocardial infarction.
  
  
  RESULTS
  Resequencing the gene coding for leukotriene C(4) synthase in an extreme risk population with more than 1500 individuals revealed 17 new mutations, of which four are likely to change protein function (211G>A (minor allele frequency, 0.0001), IVS3 + 1G>A (0.002), 374G>A (0.0006) and 451_453+10del (0.0007)). Based on genotyping 50,000 individuals, age and sex adjusted odds ratios for venous thromboembolism were 2.0 (95% CI, 1.3-3.5) for IVS3+1G>A heterozygotes vs. wild type, and 1.9 (1.5-2.7) for any mutation heterozygote vs. wild type. Corresponding values were 2.0 (1.3-3.2) and 1.5 (1.1-2.1) for ischemic stroke, and 1.0 (0.8-1.3) and 1.2 (1.0-1.4) for myocardial infarction.
  
  
  CONCLUSIONS
  Four novel mutations that are likely to change the function of leukotriene C(4) synthase were associated with increased risk of venous thromboembolism and ischemic stroke. These findings need confirmation in other independent studies. In addition, the mechanism behind these findings deserves further investigation.
authors.affiliation: Department of Clinical Biochemistry, Herlev Hospital, Copenhagen University Hospital, Copenhagen, Denmark.
authors.forename: J J
authors.initials: JJ
authors.lastname: Freiberg
authors.forename: A
authors.initials: A
authors.lastname: Tybjaerg-Hansen
authors.forename: B G
authors.initials: BG
authors.lastname: Nordestgaard
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002318:Cardiovascular Diseases / Q000235:genetics*; D016022:Case-Control Studies; D003430:Cross-Sectional Studies; D003718:Denmark; D005260:Female; D020022:Genetic Predisposition to Disease; D014644:Genetic Variation; D005838:Genotype; D005982:Glutathione Transferase / Q000235:genetics*; D006579:Heterozygote; D006801:Humans; D007511:Ischemia / Q000473:pathology; D008297:Male; D008875:Middle Aged; D009154:Mutation; D016017:Odds Ratio; D011446:Prospective Studies; D012307:Risk Factors; D012737:Sex Factors; D020521:Stroke / Q000473:pathology
chemical_list: D005982:Glutathione Transferase; C041116:leukotriene-C4 synthase