Role of C807T polymorphism of ITGA2 gene of collagen receptor and platelet aggregation activity in patients with arterial hypertension
Aim. To study the prevalence of various C807T polymorphism variants of the ITGA2 gene and to analyze the association of this polymorphism with platelet aggregation activity in hypertensive patients. Methods. 47 patients with arterial hypertension treated at the Clinical Cardiology Dispensary (Perm) were included in the study. Genotyping of C807T polymorphism (rs 1126643) was carried out by the method of polymerase chain reaction with the subsequent identification of the single nucleotide polymorphic variant of ITGA2 gene by the method of allele-specific polymerase chain reaction. Platelet aggregation activity was investigated by the impedance method using TRAP-6 reagent as an inducer of aggregation. Results. The prevalence of C/C, C/T, T/T genotypes of ITGA2 gene among hypertensive patients was 18 (38.3%), 23 (48.9%) and 6 (12.8%), respectively. A comparative analysis of platelet aggregation activity with TRAP-6 reagent revealed statistically significant differences between the groups of patients carrying different genotypes [103.5 (67.0; 121.0) AU in homozygotes -807CC versus 52.5 (48; 83) AU in homozygotes -807TT, p=0.045]. In the group of patients with reduced platelet aggregation activity (TRAP-test less than 94 AU), the carriage of the unfavorable T allele prevailed in comparison with the group of patients with its normal level (OR=3.81, 95% CI 1.38-10.54; p=0.008). In patients of this group, there was a significant increase in the frequency of occurrence of heterozygotes -807CT (OR=4.75, 95% CI 1.24-18.19; p=0.009), as well as an increase in the frequency of occurrence of homozygotes for the variant allele -807TT (OR=2.88, 95% CI 0.31-27.07; p=0.009) compared with the group of patients with a normal level of aggregation. Conclusion. The prevalence of C/C, C/T, T/T genotypes of ITGA2 gene among patients with arterial hypertension is comparable to the data of European researchers: carriers of T allele of ITGA2 gene may have a higher risk of developing cardiovascular events; the molecular mechanism of the relationship of reduced platelet aggregation activity and carriage of the unfavorable T allele of ITGA2 gene requires further studies.