Platelet Surface Collagen Receptor Polymorphisms: Variable Receptor Expression and Thrombotic/Hemorrhagic Risk

Glycoprotein Ia gene C807T polymorphism and risk for major adverse cardiac events within the first 30 days after coronary artery stenting

The glycoprotein complex Ia/IIa (GP Ia/IIa) is a major collagen receptor on platelets and other cell types. Recently, linked polymorphisms within the coding region of the GP Ia gene (C807T and G873A) were identified that are related to GP Ia/IIa surface expression. The T807/A873 allele is associated with high expression, whereas the C807/G873 allele is associated with low surface expression of GP Ia/IIa. Subsequently, the T807 allele was found to be associated with coronary and cerebral infarction in younger patients. Platelet adhesion to the vessel wall plays a pivotal role in thrombosis after coronary artery stent placement. The goal of this study was to test whether C807T polymorphism is associated with a higher incidence of thrombotic events following coronary stenting. Consecutive patients treated with coronary stent placement (n = 1797) were genotyped for C807T polymorphism with polymerase chain reaction and allele-specific fluorogenic probes. The composite end point was defined as death, myocardial infarction, or urgent target vessel revascularization within 30 days of stent implantation. The genotype distribution of the study population was CC in 36.5%, CT in 46.7%, and TT in 16.8% of the patients. The incidence of the composite end point was 6.5% in T allele carriers and 5.3% in noncarriers (odds ratio for T allele carriage 1.23 [95% confidence interval, 0.81-1.86],P = .33). After adjusting for other baseline characteristics, the odds ratio for the composite end point was 1.15 (0.76-1.75). Therefore, C807T genotype has no significant influence on the major adverse events occurring after coronary artery stenting.