4G allele of one base pair insertion/deletion polymorphism (4G/5G) at plasminogen activator inhibitor-1 (PAI-1) was associated with increased plasma activity of PAI-1. Increased plasma PAI-1 activity was associated with increase risk of coronary artery disease (CAD). However, there was a controversy whether 4G allele increases the risk of CAD. We investigated relationship between 4G/5G genetic polymorphism and CAD in Korean population.

We studied 453 patients-145 patients with normal coronary angiogram (NL), 106 with stable angina (SA), 104 with unstable angina (UA) and 98 with myocardial infarction (MI)-characterized by coronary angiography.

1) Korean had higher 4G allele frequency than Caucasian (4G:5G=0.60:0.40 in Korean). 2) There were no allele or gene frequency difference of 4G/5G polymorphism between CAD group and NL group (4G:5G=0.61:0.39 in CAD, 0.59:0.41 in NL, p=0.58). 3) 4G allele was not associated with increased risk of acute coronary syndrome (4G:5G=0.60:0.40 in SA, 0.59:0.41 in UA, and 0.57:0.43 in MI, p=0.84). 4) 4G allele had no influence on progression of coronary artherosclerosis (4G:5G=0.58:0.42 in single vessel disease, 0.58:0.42 in two vessel disease, and 0.56:0.44 in three vessel disease, p=0.82). 5) 4G was not an independent risk factor of CAD even after adjusted with other risk factors.

In Korean, 4G/5G polymorphism of PAI-1 gene has no relationship with development, progression of coronary artery disease.