Blood pressure in relation to three candidate genes in a Chinese population.
OBJECTIVE
In a prospective analysis of a Caucasian population, we recently found that the genes encoding angiotensin-converting enzyme (ACE, I/D polymorphism), alpha-adducin (Gly460Trp) and aldosterone synthase (-344C/T) jointly influence the incidence of hypertension. We therefore investigated the association between blood pressure and these three genes in a Chinese population.


METHODS
We genotyped 479 Han Chinese from 125 nuclear families recruited in northern China via random sampling (approximately 75%) and at specialized hypertension clinics (approximately 25%). We performed population-based and family-based association analyses using generalized estimating equations (GEE) and the quantitative transmission disequilibrium test (QTDT), respectively, while controlling for covariables.


RESULTS
The participants included 239 (49.9%) women and 132 (27.6%) hypertensive patients, of whom 77 took antihypertensive drugs. The blood pressure, measured at the subjects' homes, averaged 126/80 mmHg. Mean values of urinary sodium, potassium and Na/K ratio were 226 mmol/day, 37 mmol/day and 6.31, respectively. In adjusted GEE analyses, systolic blood pressure was 9.3 mmHg (95% confidence interval 3.6-15.0 mmHg; P = 0.001) and 14.6 mmHg (95% confidence interval 3.4-25.8 mmHg; P = 0.01) higher in the ACE DD than II subjects among the alpha-adducin TrpTrp (n = 141) and aldosterone synthase CC (n = 33) homozygotes, respectively (P < or =0.05 for interactions of the ACE genotype with the alpha-adducin and aldosterone synthase polymorphisms). Among 40 informative offspring homozygous for the alpha-adducin Trp allele, systolic blood pressure was significantly associated with transmission of the ACE D allele (beta = 5.5 mmHg; P = 0.046).


CONCLUSIONS
The ACE I/D, alpha-adducin Gly460Trp and aldosterone synthase -344C/T polymorphisms interact to influence systolic blood pressure in Chinese, suggesting that these genes might indeed predispose to hypertension, especially in an ecogenetic context characterized by a high salt intake.
Wang
Ji-Guang
JG
Hypertension Division, Cardiovascular Institute and Fuwai Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China. jiguang.wang@med.kuleuven.ac.be
Liu
Lifang
L
Zagato
Laura
L
Xie
Jinxiang
J
Fagard
Robert
R
Jin
Kugen
K
Wang
Jinxiang
J
Li
Yan
Y
Bianchi
Giuseppe
G
Staessen
Jan A
JA
Liu
Lisheng
L
D000328:Adult; D044466:Asian People / Q000235:genetics*; D001794:Blood Pressure / Q000235:genetics; D002148:Calmodulin-Binding Proteins / Q000235:genetics*; D019405:Cytochrome P-450 CYP11B2 / Q000235:genetics*; D005192:Family Health; D005260:Female; D020022:Genetic Predisposition to Disease / Q000453:epidemiology; D005838:Genotype; D006801:Humans; D006973:Hypertension / Q000453:epidemiology / Q000235:genetics*; D008297:Male; D008875:Middle Aged; D007703:Peptidyl-Dipeptidase A / Q000235:genetics*; D011446:Prospective Studies; D012307:Risk Factors; D000099291:Adducins
D002148:Calmodulin-Binding Proteins; D019405:Cytochrome P-450 CYP11B2; D007703:Peptidyl-Dipeptidase A; D000099291:Adducins