GLYCOPROTEIN III A (A1 VS.A2)
- GLYCOPROTEIN III A (A1 VS.A2)
- Start Date
- Expiration Date
- CPT Codes
- 83890; 83892; 83896; 83903; 83912
- Reference Test
Lavender, EDTA Whole Blood
Collect 2 tubes for leukopenic patients.
- Transport Info
Refrigerated until shipped
Ship sample at room temperature
- Fasting Required?
- Patient Instructions
- Reference Range
Glycoprotein IIIa is part of a receptor, the glycoprotein IIb/IIIa receptor, on the surface of platelets.
This complex binds fibrinogen and von Willibrand factor and it is essential for platelet aggregation and hemostasis. Two allelic polymorphisms, the P1A1 and the P1A2 polymorphisms (C to T substitution at base 196 of the mRNA in exon 2) have been described. The P1A2 is associated with premature (<55y of age) myocardial infarction, unstable angina and re-occlusion after PCTR. In addition, the P1A2 allele is associated with coronary stent thrombosis, adds ratio, 5.26.
The use of stents in occlusive coronary vascular disease has increased dramatically in the past 3 years. Anti platelet therapy with glycoprotein IIb/IIIa inhibitors may be useful in preventing stent re-stenosis and stent thrombosis. although care must be taken that bleeding complications are avoided. Currently, only intravenous inhibitors are available; oral inhibitors are in phase II-III trials in humans.
The genotype frequencies for this polymorphism are: P1A1/P1A1, 64%; P1A1/P1A2, 34%; and P1A2/P1A2, 2.4%.