Background and objective: To study the prevalence of variable number of tandem repeats (VNTR) polymorphism in platelet membrane glycoprotein (GP) Ib alpha in a Chinese Han population and to determine the relationship between VNTR polymorphisms and aspirin resistance.
Methods: Three hundred healthy individuals and 110 patients with cerebral infarction volunteered to participate in this study. The genotype status of all participants was determined by polymerase chain reaction-restriction fragment length polymorphism analysis. Platelet aggregation in patients with cerebral infarction receiving aspirin (100 mg/day) for at least 7 days, was measured by optical transmission aggregometry.
Results and discussion: Only three alleles of GP Ib alpha, namely, B, C and D, were found. Type A was not found in the Chinese Han participants. Aspirin-sensitive patients were significantly more often of CC genotype than aspirin-semi-responders.
Conclusions: Only three types of alleles B, C and D were detected in the north-eastern region of China. The CC genotype of the VTNR polymorphism in GPIb appears to be more sensitive to the inhibitory action of low-dose aspirin.