Insertion/deletion (I/D) polymorphism at the locus for angiotensin I-converting enzyme and myocardial infarction

Male (n = 185) and female (n = 49) survivors of myocardial infarction (MI) below 56 and 61 years of age, respectively, were compared to 366 controls with respect to distribution of genotypes in an insertion/deletion (ID) polymorphism at the angiotensin I-converting enzyme (ACE) locus. The frequency of the DD genotype (homozygosity for the deletion allele) was significantly lower among male patients than controls (22.7% versus 34.9%, p = 0.011). In a "low-risk" group, defined as having less than the sex-specific, age-adjusted median values of body mass index (BMI) and apolipoprotein B (apoB), respectively, and absence of treatment with lipid-lowering drugs, the prevalence of the DD genotype was not statistically different between male patients and controls. In a male "high-risk" group (those individuals who had not been defined as "low-risk" subjects), the prevalence of the DD genotype was 20.9% in patients and 38.3% in controls (p = 0.002). In women, no significant differences in genotype frequencies between patients and controls were found in the whole sample or in any subgroup. These results appear to be at variance with data reported recently by Cambien et al. (1992). The difference may be due to chance, undetected selection biases, different gene-environment interactions between Norway and France or Ireland, or to preferential loss of DD individuals in our male "high-risk" group.