Integrin, alpha 2 gene C807T polymorphism and risk of ischemic stroke: a meta-analysis

Platelet adhesion to fibrillar collagen via the membrane glycoprotein (GP) Ia/IIa (alpha2beta1), is a crucial event in the pathogenesis of arterial occlusive disorders. The C807T single nucleotide polymorphism of the integrin, alpha 2 (ITGA2) gene has been shown to correlate with the platelet GPIa/IIa density. Consequently, subjects with the 807T allele, who express the highest receptor density, might have an increased potential of platelet adhesion and, hence an increased risk of cerebrovascular disease. However, the research findings remain controversial.

A comprehensive electronic search was carried out up until November 2005 and 7 independent studies with a maximum of 774 cases and 1074 controls were analyzed using random effects models.

The pooled frequency of the T allele was 36.33% in cases and 37.01% in controls. The T versus the C allele contrast gave an OR of 1.11 (95% confidence interval=0.827-1.499). All the other comparisons failed to show any significant result. Age, sex, and cardiovascular risk factors were included as covariates into a meta-regression model without a significant finding.

This meta-analysis do not support an association between the C807T polymorphism of ITGA2 gene and stroke, but given the significant between study heterogeneity and the small number of studies, the summary effect should be interpreted carefully.