In the subsets of MI cases and those with younger CAD onset (<50 years) the associations with C5 (A2416G) remained (MI only P = 0.006; <50 years P = 0.04) and additional significant associations were observed with interleukin 1 alpha (IL1α) C549T (MI only P = 0.02; <50 years P = 0.02). This evidence concerns the gene IL1A and myocardial infarction.