Negative association of endothelial nitric oxide gene polymorphism with hypertension in Turkish patients: effect of ecNOS polymorphism on left ventricular hypertrophy.
BACKGROUND
Endothelial nitric oxide synthase produces nitric oxide which is involved in many physiologic regulatory functions. Variable number of tandem repeats in intron 4 of endothelial nitric oxide synthase gene are reported to be associated with blood pressure regulation. Nitric oxide is involved in regulation of cardiomyocyte genes but it is not known If endothelial nitric oxide synthase 4 gene polymorphisms are related with left ventricular hypertrophy. We studied endothelial nitric oxide synthase 4a/b allele status in hypertensive and normotensive patients and echocardiographic parameters in a subgroup of hypertensive group.


METHODS
We performed a case-control study involving 110 Turkish hypertensive patients and 87 controls. All subjects were genotyped for endothelial nitric oxide synthase 4a/b polymorphism. Echocardiographic measurements were obtained in 94 of the hypertensive patients.


RESULTS
Endothelial nitric oxide synthase 4a/b genotype frequencies were 6.4%, 23.6%, 70% in hypertensives and 1.1%, 18.4%, 80.5% in controls for a/a, a/b, b/b, respectively. Left ventricular dimensions, mass and diastolic indices were not different across endothelial nitric oxide synthase 4 genotypes. Patients with 4a/a genotype had higher interventricular septal thickness than the other group; 14.83(1.6), 11.91(1.51), 12.21(1.56) for a/a, a/b, b/b, respectively and p = 0.0001.


CONCLUSIONS
Endothelial nitric oxide synthase 4a/b gene polymorphism is not associated with hypertension in Turkish patients. 4a/a genotype was associated with higher interventricular septal thickness in hypertensive patients.
Olcay
Ayhan
A
Department of Cardiology, Istanbul School of Medicine, Istanbul, Turkey. aolcay@excite.com
Ekmekci
C Gokhan
CG
Ozbek
Ugur
U
Sezer
Murat
M
Barcin
Cem
C
Arslan
Erol
E
Boztosun
Bilal
B
Nisanci
Yilmaz
Y
D016022:Case-Control Studies; D004252:DNA Mutational Analysis; D005260:Female; D020022:Genetic Predisposition to Disease / Q000453:epidemiology / Q000235:genetics; D006801:Humans; D006973:Hypertension / Q000000981:diagnostic imaging / Q000201:enzymology* / Q000453:epidemiology* / Q000235:genetics; D017379:Hypertrophy, Left Ventricular / Q000000981:diagnostic imaging / Q000201:enzymology* / Q000453:epidemiology* / Q000235:genetics; D015994:Incidence; D008297:Male; D008875:Middle Aged; D052250:Nitric Oxide Synthase Type III / Q000235:genetics*; D020641:Polymorphism, Single Nucleotide / Q000235:genetics; D018570:Risk Assessment / Q000379:methods*; D012307:Risk Factors; D013223:Statistics as Topic; D014421:Turkey / Q000453:epidemiology; D014463:Ultrasonography
C496314:NOS3 protein, human; D052250:Nitric Oxide Synthase Type III