The GPIa/IIa complex mediates platelet adhesion to collagen. Although the GPIa C807T polymorphism does not change the amino acid sequence, it has been associated with the difference in the GPIa/IIa receptor levels on the platelet surface. Carriers of the 807T allele express higher levels of GPIa/IIa, while carriers of the 807C allele exhibit lower expression of the integrin. This polymorphism has been implicated to be associated with an increased risk of arterial thrombosis. Additional studies suggest this is a mild risk factor and is particularly important in synergism with known risk factors such as smoking, hypertension, diabetes or proteinuria, which may enhance its contribution to the overall cardiovascular risk.
PCR amplification followed by RFLP agarose gel electropheresis perfomed.
Platelets play an important part in arterial thrombosis; therefore, it is important to consider the role adhesion molecules of the platelet surface play in increasing arterial risk. Glycoprotein Ia/IIa is the major platelet collagen receptor and is responsible for platelet adherence to exposed vascular subendothelium. The single nucleotide polymorphism C807T allele is associated with increased collagen receptor levels and increased collagen induced platelet adhesion. Preliminary results suggest that the C807T variant of glycoprotein Ia may be a genetic risk factor for early-onset arterial thrombotic disease.
In general, screening for arterial thrombosis is best accomplished by evaluating for the traditional cardiovascular markers, such as diabetes mellitus, smoking, hypertension, and hypertriglyceridemia. The use of the glycoprotein Ia C807T assay may be of value in the following situations:
- Children, young individuals or pre-menopausal women with arterial thrombosis
- Any individual with arterial disease in the absence of atypical cardiovascular risk factors
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