The NOS 3 gene polymorphism –786T>S (rs2070744) as the risk factor of hemodynamic disorders in Northerners

Abstract

Objective . This research assessed the influence of polymorphism –786T>C (rs2070744) of the NOS3 gene on the hemodynamic impairments in the Northern residents. Design and methods . One hundred and one volunteers of Magadan region, mainly Caucasians by ethnicity, underwent molecular genetic examination, and a continuous method was used to form the study sample. DNA was isolated by phenol-chloroform extraction followed by polymorphism genotyping by the polymerase chain reaction. Results . In male Northerners, the following percentage variation in the genotype frequencies by the eNOS locus (rs2070744) was found: –786ТТ — 42,57 %, –786ТС — 43,56 %, –786СС — 13,87 %. The concentration of the eNOS *C allele was 35,64 %, the ancestral eNOS *T allele occurred with the frequency of 64,36 %. The observed distribution of frequencies of alleles and genotypes corresponded to the Hardy-Weinberg equilibrium (χ 2 (HWE) = 0.26, p > 0.05). The presence of even one eNOS *C allele in the genotype causes a significant increase in diastolic blood pressure level. The lowest blood pressure (80,3 ± 5,9 mmHg) was found in male homozygotes by the ancestral eNOS *T allele, while the T/C heterozygotes and the C/C homozygotes showed significantly higher blood pressure (83,2 ± 7,3 and 82,9 ± 3,7 mmHg, respectively). The individuals with the C/C genotype showed lower cardiovascular adaptabilities, in particular lower indicators of stroke volume (SV, 43,6 ± 3,7 mL) and cardiac output (CO, 2836,3 ± 182,4 mL/min) with a significant increase in total peripheral vascular resistance (TPVR, 3028,3 ± 252,7 dyn 2 s cm -5 ) compared to the T/T homozygotes (SV, 49,6 ± 7,9 mL; CO, 3393,1 ± 546,8 mL/min; TPVR, 2572,8 ± 559,4 dyn 2 s cm -5 ). Conclusions . This study showed that the eNOS *C allele is associated with the hemodynamic disorders. These results can be used to calculate the risk of cardiovascular pathologies at younger ages, which can develop under the North extremes.