Fibrinogen polymorphisms are not associated with the risk of myocardial infarction

In the Study of Myocardial Infarctions Leiden , we investigated the prevalence of three polymorphisms in the α‐ and β‐fibrinogen genes among 560 patients with a myocardial infarction and 646 control subjects. Secondly, we studied the relationships between these polymorphisms and fibrinogen activity and antigen levels. The Taq I, Hae III and Bcl I polymorphisms in the fibrinogen gene were not associated with myocardial infarction. As we found an association of the rare B2 allele with fibrinogen levels and a similar, but weak, effect for the rare H2 allele, we conclude that a genetic propensity to high fibrinogen levels does not affect the risk of myocardial infarction. This is evidence against a causal role for fibrinogen levels in the aetiology of myocardial infarction.