In 19 Japanese patients with myocardial infarction whose first attack occurred before the age of 50 years, significant differences were observed in the –1965 delG of PAI-1 with respect to allelic frequency, the G>A in the promoter region SNP in SM22 (TAGLN) for dominant genotype, and in two other SNPs (C>T in intron 1 of HGF, and –1965 delG of PAI-1) for recessive genotype. Here, SERPINE1 is linked to myocardial infarction.