AbstractWe investigated a possible association between the C373G (Leu125Val) polymorphism in the platelet endothelial cell adhesion molecule-1 (PECAM-1) and myocardial infarction (MI) among patients with type 2 diabetes (T2DM) in the Slovene population (Caucasians). The study population of this cross-sectional analysis consisted of 452 subjects with T2DM lasting more than 10 years: 142 patients with MI (MI group) and 310 patients (control group) with no history of coronary diseases. There were significant differences of PECAM-1 genotype distribution in patients with MI (CC=28.2%, CG=47.2% and GG=24.6%) compared with subjects in the control group (CC=17.1%, CG=53.5% and GG=29.4%). The multivariate model showed that the CC genotype of the PECAM-1 gene polymorphism (C373G) (OR=1.9, 95% CI 1.2–3.0, P=0.007) was an independent risk factor for MI. The C allele frequency was also significantly higher (P=0.005) in MI (51.8%) than in control subjects (41%). In addition, our study revealed the connection between smoking habits, the duration of diabetes and the total and LDL cholesterol serum levels and MI in Slovene T2DM patients. We suggest that the tested polymorphism of PECAM-1 (C373G) is associated with MI. Therefore, it might be used as genetic marker of MI in T2DM.