title: The HR2 haplotype of factor V is not associated with the risk of myocardial infarction.
abstract: The HR2 haplotype of the factor V gene, which contains the histidine to arginine substitution at position 1299, has been reported to be associated with reduced factor V levels. Because high factor V levels have been found to be associated with an increased risk of myocardial infarction, we examined how the presence of the R2 allele affected the risk of myocardial infarction in the case-control "Study of Myocardial Infarctions Leiden". Among 560 men with a first myocardial infarction before the age of 70 years, 9.5% were heterozygous carriers of the R2 allele. The control group consisted of 646 men, in which 9.9% were heterozygous and 0.2% homozygous carriers of the R2 allele. The risk of myocardial infarction in the presence of the R2 allele was not increased (odds ratio, 0.9; 95% confidence interval 0.6 to 1.4). Exclusion of factor V Leiden carriers did not change this result. The risk was 4.4-fold increased for smokers who carried the R2 allele compared to non-smoking noncarriers. No synergy was found between metabolic risk factors and the presence of the R2 allele. We conclude that the risk of myocardial infarction for men in the presence of the R2 allele of the His1299Arg polymorphism is neither increased nor decreased.
authors: Department of Clinical Epidemiology, Leiden University Medical Center, The Netherlands.
authors: C J
authors: CJ
authors: Doggen
authors: M C
authors: MC
authors: de Visser
authors: H L
authors: HL
authors: Vos
authors: R M
authors: RM
authors: Bertina
authors: V M
authors: VM
authors: Cats
authors: F R
authors: FR
authors: Rosendaal
mesh_terms: D000328:Adult; D000368:Aged; D000483:Alleles; D005165:Factor V / Q000235:genetics*; D020022:Genetic Predisposition to Disease; D014644:Genetic Variation; D006239:Haplotypes; D006579:Heterozygote; D006801:Humans; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000209:etiology / Q000235:genetics*; D011110:Polymorphism, Genetic; D012306:Risk
chemical_list: D005165:Factor V