Impact of Obesity and Nitric oxide Synthase Gene Polymorphism on Essential Hypertension at Children

Background: Hypertension is a multifactorial disease caused by environmental, metabolic and genetic factors, but currently it is little known about the complex interplay between these factors and blood pressure.

The aim of the study was: estimation of the relations between carrying of gene polymorphism Glu298Asp of endothelial nitric oxide synthase gene and risk of arterial hypertension at children with obesity/overweight.

Methods: The investigation included 120 children with obesity/overweight at the age of 10-16 (n=62; 51,67% - hypertensives and n=58; 48,33% - normotensives). The control group included 50 children with normal tension and weight of the similar age - 26 boys and 24 girls, without family history including arterial hypertension and obesity. The protocol of the study was approved by the Medical Ethics Committee.

Polymorphism Asp298Glu of the gene NOS₃ (polymorphism Glu298Asp of endothelial nitric oxide synthase gene) was identified through the method of analyzing of the length of the fragments amplified and polymorph fragments of restriction.

Results: At children with overweight/obesity both hypertensives and normotensives was registered a greater frequency of the genotype AG of NOS₃, but the proportion of the homozygous children according to G allele was greater at hypertensives (25,81%), than at normotensives (10,34%) and minimal in control group (2,00%), where dominated carrying of the genotype AA (46,00%). Homo/heterozygous holders of G allele showed higher chances of realization of arterial hypertension (OR 9,71; 95% CI: 3,05-32,98; p<0,001), they had advanced degree of obesity, mainly abdominal, dyslipidemia and higher serum values of insulin than homozygous holders according to A allele.

Conclusion: Our results suggest that at children with overweight/obesity carrying homo/heterozygous of G allele of NOS₃ the risk of realization of arterial hypertension and metabolic disorders is higher. Appreciation of the polymorphism of this gene at children with overweight will initiate taking measures in the early stages.