In a European study an insertion (I)/deletion (D) polymorphism in the angiotensin converting enzyme (ACE) gene has been shown to be associated with the risk of myocardial infarction (MI). In the same study, we investigated the association of the polymorphism with a parental history of fatal MI. There was an excess of both DD (odds ratio 2.6, p = 0.02) and ID (odds ratio = 1.9, p = 0.08) genotypes among those having a parental history of MI, confirming that genetic variation in the ACE locus could be involved in the risk of MI.