Interaction Between G894T Mutation In ENOS Gene And Abnormality Of Waist-to-Hip Ratio Or Overweight In Essential Hypertension

Objective To analyze the effects of G894T(Glu298Asp) mutation in eNOS gene, M235T mutation in AGT gene and abnormality of waist-to-hip ratio(WHR),overweight and the interactions between the four factors on essential hypertension(EH).Methods The study population came from a screening survey carried out in four communities in Qingdao.A total of 235 patients diagnosed as essential hypertension, without anti-hypertensive medication,and 240 healthy subjects were enrolled in the current study.Polymerase chain reaction(PCR) and restriction fragment length polymorphism(RFLP) were performed to detect the polymorphism of G894T in the endothelial nitric oxide synthase(eNOS ) gene and M235T in the angiotensinogen(AGT) gene.Additive model was used to analyze the interactions between these genes and overweight or abnormal Waist-to-Hip Ratio(WHR).Results eNOS gene T allele frequency(18.94%) and AGT gene T allele frequency (46.81%) in patients were significantly higher than those in controls(12.71%, 37.71%),(χ~2=6.927,8.677,P＜0.01 );The frequency of overweight(86.81%) and frequency of abnormality of WHR(69.79%) in patients were significantly higher than those in controls(70.83%,47.92%),(χ~2=18.100,23.433,P＜0.001).After adjusting age,gender,drinking,smoking,body mass index and blood fats by logistic regression,G894T mutation of eNOS gene and abnormality of WHR showed a positive interaction.Synergy index between the G894T mutation in eNOS gene and Abnormality of WHR was 1.542,attributable interaction was 0.909,attributable interaction percentage was 25.34%,pure attributable interaction percentage was 35.14 %.M235T mutation of AGT gene and abnormality of WHR also showed a positive interaction.After adjusting the confounding factors mentioned above by logistic regression,the indexes mentioned above were 1.930,1.560,36.82%and 48.19% respectively.There was also a positive interaction between M235T mutation in AGT gene and overweight,the indexes were 2.241,0.598,28.75%and 55.37%respectively after adjustment of confounding factors by logistic regression.In addition,there was also a positive interaction between polymorphisms of T allele of eNOS and T allele of AGT,the indexes were 1.600,1.520,30.07%and 37.48%respectivelyafter adjustment of confounding factors by logistic regression. Conclusions T allele of eNOS,T allele of AGT,overweight and abnormality of WHR were the risk factors of essential hypertension.The interactions among T allele of eNOS,T allele of AGT and abnormality of WHR had positive effects on essential hypertension in this studied population.To control abnormality of WHR in the population who had T allele of eNOS or T allele of AGT and abnormality of WHR simultaneously could produce marked decrease of getting essential hypertension in general population.