Polymorphisms of genes affecting thrombosis and risk of myocardial infarction

Background As thrombosis is an essential factor in the pathogenesis of acute myocardial infarction (AMI), the genes of proteins affecting haemostasis are good candidate genes for AMI. Design Associations of the known polymorphisms of the coagulation factor VII (FVII) gene (R353Q), the coagulation factor XIII (FXIII) gene (V34L) and the glycoprotein Ia (Gp1a) gene (C807T) with the occurrence of AMI were studied in 142 AMI survivors and 142 age- and sex-matched control subjects. Results Among those who smoked, the L34 allele of the amino acid FXIII polymorphism was less common in the AMI patients (16%) than in the controls (27%) (P = 0.06), suggesting a possible interaction of AMI risk between the FXIII genotype and smoking status. No differences in the allele or genotype frequencies of the studied polymorphisms were seen between the whole study groups. Logistic regression analysis showed the carriers of the L34 allele of the FXIII amino acid polymorphism to have a significantly (P = 0.03) lower AMI risk compared with those homozygous for the V34 allele (odds ratio = 0.54, 95% confidence interval 0.31-0-93). Conclusion The L34 allele of the amino acid polymorphism of the FXIII gene is associated with a decreased risk of AMI, and this protecting association seems to be more pronounced in smokers.