Association Of ENOS A/b And ACE I/D Polymorphisms With Essential Hypertension In Han Chinese In Hubei

Objective:Hypertension is characterized by an increased systemic arterial pressure. It affects nearly 120 million people with an incidence rate of 8%-12%in China.More than 95%hypertension is essential hypertension(EH).Hypertension is a major risk factor of cardio-cerebro-vascular diseases.It is estimated that 30%-60%blood pressure varability in human is determined by genetic factors.The objective of this study is to test the association between eNOS a/b and ACE I/D polymorphism with EH in Hubei Han Chinese.Methods:Both sib-pairs(within-family control) and random case-control designs were used.Polymerase chain reaction(PCR) and gel electrophoresis is used to genotype for eNOS a/b and ACE I/D polymorphism in 434 EH patients and 411 subjects with normal blood pressure.Association test is conducted using SPSS 11.5 statistical software.Results:(1) There were significant differences in the genotypic and allelic frequencies of the eNOS a/b polymorphism between cases and controls in all subjects (genotype:χ~2=4.923,P=0.027;allele:χ~2=5.413,P=0.02).In sib-pairs design,no differences were observed between sibpair cases and controls(genotype:χ~2=1.516, P=0.218;allele:χ~2=1.771,P =0.183).In random case-control design,the genotypic frequencies of the eNOS a/b polymorphism showed weak association trend with EH,and the allelic frequencies were significantly different between cases and controls(genotype:χ~2=3.52,P= 0.061;allele:χ~2=5.052,P=0.025).Logistic regression analysis indicated that aa+ab genotype was significantly associated with EH in all subjects(OR= 1.451, 95%CI:1.043-2.017).Multivariate logistic regression analysis suggested that age,FPG, eNOS a/b were independent risk factors of EH.Meta analysis reveals that eNOS a/b polymorphism is associated with EH in Han Chinese,aa+ab genotype increasing risk of EH(OR=1.87,P≤0.001).(2) There were significant differences in the genotypic and allelic frequencies of the ACE a/b polymorphism between EH cases and controls in all subjects(genotype:χ~2=8.434,P=0.015;allele:χ~2=9.445,P=0.002).Significant differences were also obversed in sibpair cases and controls(genotype:χ~2=1.125,P=0.021;allele:χ~2=7.867, P=0.005).In random case-control subjects,there were no significant differences in the genotypic frequencies of the ACE I/D polymorphism,but allelic frequencies are significantly differet between cases and controls(genotype:χ~2=4.68,P=0.096;allele:χ~2=4.395,P=0.036).Logistic regression analysis indicated that DD genotype was significantly associated with EH in all subjects(OR=1.723,95%CI:1.191-2.492).Meta analysis reveals that ACE I/D polymorphism is association with EH in Han Chinese, subjects with DD genotype having an increated risk of EH(OR=1.72,P≤0.001).Conclution:eNOS a/b and ACE I/D polymorphisms are associated with EH in Hubei Han Chinese.