G894T Polymorphism Research Articles

Association of endothelial nitric oxide synthase gene G894T polymorphism with essential hypertension in an adult Pakistani Pathan population

This retrospective, case–control study was carried out to find putative correlations of eNOS G894T polymorphism with essential hypertension (EHT) amongst adult Pakistani Pathans. We investigated a sample population of 332 (154 men, 178 women) comprising groups of 146 hypertensives (HTs) and 186 normotensives (NTs) by assays based on polymerase chain reaction followed by restriction endonuclease analysis. The distribution of the genotypes or alleles was not statistically different in hypertensive and normotensive groups. In conclusion, the present study in a population of Pakistani adult Pathans does not support the association of the eNOS gene G894T polymorphism to essential hypertension.

NOS3 Gene Polymorphisms and Exercise Hemodynamics in Postmenopausal Women

We tested whether the G894T and T-786C NOS3 polymorphisms were associated with exercise cardiovascular (CV) hemodynamics in sedentary, physically active, and endurance-trained postmenopausal women. CV hemodynamic parameters including heart rate (HR), systolic (SBP) and diastolic (DBP) blood pressures and cardiac output (Q), as determined by acetylene rebreathing, stroke volume (SV), arteriovenous oxygen difference (a-vO2 diff), and total peripheral resistance (TPR) were measured during submaximal (40, 60, 80 %) and maximal (approximately 100 % VO2max) exercise. NOS3 G894T genotype was not significantly associated, either independently or interactively with habitual physical activity (PA) level, with SBP, Q, TPR, or a-vO2 diff during submaximal or maximal exercise. However, NOS3 894T non-carriers had a higher submaximal exercise HR than NOS3 894T allele carriers (120 +/- 2 vs. 112 +/- 2 beats/min, p = 0.007). NOS3 894T allele carriers had a higher SV than 894T non-carriers (78 +/- 2 vs. 72 +/- 2 ml/beat, p = 0.03) during submaximal exercise. NOS3 894T non-carriers also had a higher maximal exercise HR averaged across habitual PA groups than T allele carrier women (165 +/- 2 vs. 158 +/- 2 beats/min, p = 0.04). NOS3 894T allele carriers also tended to have a higher SV during maximal exercise than 894T non-carriers (70 +/- 2 vs. 64 +/- 2 ml/beat, p = 0.08). NOS3 T-786C genotype was not significantly associated, either independently or interactively, with any of the CV hemodynamic measures during submaximal or maximal exercise. These results suggest an association of NOS3 G894T genotype with submaximal and maximal exercise CV hemodynamic responses, especially HR, in postmenopausal women.

Endothelial nitric oxide synthase G894T gene polymorphism in Chilean subjects with coronary artery disease and controls

Background Nitric oxide (NO) from the endothelium, produced by oxidation of l-arginine to l-citruline for the action at the endothelial nitric oxide synthase (eNOS), is considered an important atheroprotective factor. The Glu298Asp (G894T) polymorphic variant of the eNOS gene has been implicated in the development of coronary artery disease (CAD). We investigated the association between occurrence of CAD documented by angiography and the G894T polymorphism of the NOS3 gene in Chilean individuals. Methods A total of 112 unrelated patients with diagnosis of CAD and 72 controls were included in this study. G894T gene polymorphism was analyzed by polymerase chain reaction (PCR) and restriction fragment length polymorphism (RFLP). Results The frequency of TT homozygous genotype for G894T polymorphism was 7% in CAD patients and 1% in the control group. However, the genotype distribution and allele frequencies were not significantly different between CAD and control subjects ( P > 0.05). Moreover, the odds ratio for CAD associated with the T variant failed to reach statistical significance (OR = 1.5; 95% CI: 0.87–2.59, P > 0.05). Conclusion These findings suggest that the G894T polymorphism of the eNOS gene was not associated with CAD in Chilean individuals.

Hyperhomocysteinemia, Endothelial Nitric Oxide Synthase Polymorphism, and Risk of Coronary Artery Disease

Hyperhomocysteinemia is an independent, graded risk factor for coronary artery disease (CAD). The G894T variant of endothelial nitric oxide synthase (eNOS) was postulated to be associated with hyperhomocysteinemia and could influence individual susceptibility to CAD. The aims of this study were to investigate (a) the relationship of the eNOS G894T polymorphism with the presence and the severity of CAD and (b) the possible relationship between hyperhomocysteinemia and the eNOS G894T variant for the risk of CAD severity in a Tunisian population. We used PCR with restriction fragment length polymorphism analysis to detect the G894T variant of the eNOS gene in 100 patients with CAD and 120 healthy controls. The severity of CAD was expressed by the number of affected vessels. Total plasma homocysteine concentrations were determined by direct chemiluminescence assay. The frequencies of the eNOS GG, GT, and TT genotypes in the CAD group were significantly different from those in the control group (45%, 44%, and 11% vs 60%, 35.8% and 4.2%, respectively; P = 0.035). There was no association between the eNOS G894T genotype frequencies and the number of stenosed vessels (P = 0.149). In the CAD group, the coexistence of the 894 GT or TT genotypes and hyperhomocysteinemia led to an increased risk of CAD severity. The G894T polymorphism of the eNOS gene is associated with the presence of CAD, and in conjunction with hyperhomocysteinemia, increased the risk of CAD severity in a Tunisian population.

A polymorphism in the adiponectin gene influences adiponectin expression levels in visceral fat in obese subjects

Reduced serum adiponectin levels have been found in obesity and type 2 diabetes and variations in the adiponectin gene (APM1) have been associated with type 2 diabetes and features of the metabolic syndrome in different populations. Here, we investigated the expression of APM1 in adipose tissue and studied the relationship between variation in APM1 expression, the APM1 G276T polymorphism, the common PPARG Pro12Ala polymorphism and clinical features of 36 morbidly obese (body mass index (BMI) 41.5 +/- 4.9 kg/m2) nondiabetic subjects. APM1 mRNA expression in visceral fat was correlated with serum adiponectin levels (r = 0.54, P = 0.012). In visceral, but not in subcutaneous, adipose tissue APM1 mRNA level was 38% higher among carriers of the APM1 G276T T allele (G/T and T/T) than among carriers of the G/G genotype (0.91 +/- 0.06 for G/T and T/T carriers vs 0.66 +/- 0.09 for G/G carriers, P = 0.013). Carriers of the T allele also had significantly higher body fat percent compared to G/G carriers (65 +/- 6 vs 56 +/- 10%, P = 0.011). Our results indicate that genetic variation in APM1 influences the expression of the gene in visceral adipose tissue and suggest a potential role for such variation in regulation of body fat accumulation in obese subjects.

ENOS Gene Affects Red Cell Deformability: Role of T-786C, G894T, and 4a/4b Polymorphisms

Plasma viscosity and erythrocyte deformability play a key role in maintaining and regulating microcirculation. In vitro and in vivo studies suggested a role for nitric oxide (NO) in modulating flow-mediated vasodilatation and red blood cell deformability. Impaired NO availability due to mutations in eNOS gene might contribute to the altered haemorheologic state. The aim of this study was to investigate the role of eNOS T-786C, G894T, and 4a/4b polymorphisms in modulating the haemorheologic state in a clinical condition characterized by a microcirculatory disorder. Eighty patients with idiopathic sudden sensorineural hearing loss (ISSHL) and 80 healthy subjects were studied. By using a dominant model of inheritance, we found a significant association between eNOS 894T rare variant and ISSHL (odds ratio [OR] 894TT+GT = 2.08, p = 0.03) after adjustment with traditional vascular risk factors. A higher percentage of altered red cell deformability both in patients and in controls carrying the eNOS rare variants was found in comparison to subjects carrying the wild type. Apart from the disease, eNOS T-786C and G894T polymorphisms independently affected the deformability index (OR, -786CC+TC = 2.81, p = 0.01 and OR, 894TT+GT = 2.5, p = 0.02, respectively), in particular in subjects in whom the contemporary presence of the two rare alleles was observed (OR, -786CC+TC and 894TT+GT combined genotype = 6.9, p<0.0001). Our study documented that eNOS gene affects the red blood cell deformability, so possibly contributing to ISSHL, which may represent a suitable model of microcirculatory disorder.

ENOS G894T polymorphism as a mild predisposing factor for abdominal aortic aneurysm

Abdominal aortic aneurysm (AAA) represents a chronic degenerative condition associated with atherosclerosis. Actually, data from experimental and clinical studies suggest that nitric oxide (NO) is a modulator in maintaining endothelial function and antithrombotic intravascular environment. Reduced vascular NO generation in subjects carrying the rare variants of the eNOS gene might predispose to AAA. No information is available about the influence of the eNOS gene T-786C, G894T, and 4a/4b polymorphisms in the susceptibility to the disease. In this study, we evaluated the role of these polymorphisms in the predisposition to AAA and their influence in hypertensive and normotensive patients. We studied 250 consecutive patients with AAA referred to the Unit of Vascular Surgery of the University of Florence compared with 250 truly healthy subjects with a negative history of vascular diseases. All subjects, patients, and controls, underwent duplex scanning examination, and to assess the presence of other atherosclerotic localizations, all patients underwent clinical and instrumental examinations. A significant difference in genotype distribution and allele frequency was observed for eNOS G894T but not for T-786C and 4a/4b polymorphisms. At the multivariate analysis after adjustment for traditional vascular risk factors and other atherosclerotic localizations, the eNOS 894T variant was significantly associated with AAA, according to dominant and recessive models (dominant model odds ratio [OR]: 2.2, 95% confidence interval [CI]: 1.21-3.93, P = .007; recessive model OR: 2.7, 95% CI: 1.42-5.20, P = .002). When patients with other atherosclerotic localizations were excluded from the analysis, the 894T variant still remained associated with the predisposition to AAA, according to the models considered (dominant model OR: 2.1, 95%CI: 1.23-3.92, P = .007; recessive model OR: 2.8, 95%CI: 1.45-5.24, P = .002). The present study showed that the eNOS G894T polymorphism is a mild modulator of the predisposition to AAA apart from traditional risk factors, suggesting a genetic influence on the molecular mechanisms responsible for this complex disease.

Genetic Polymorphism on Endothelial Nitric Oxide Synthase Affects Endothelial Activation and Inflammatory Response During the Acute Phase of Myocardial Infarction

This study sought to evaluate the effect of genetic polymorphism G894T on endothelial nitric oxide synthase (eNOS); on the risk for myocardial infarction (MI); and on the release of von Willebrand factor (vWF), interleukin (IL)-6, IL-1b, and oxidized low-density lipoprotein (ox-LDL) levels during the acute phase of MI and one year after the event. Genetic polymorphism G894T on eNOS has been associated with increased cardiovascular risk. However, its role during the acute phase of MI is unknown. The study population consisted of 228 patients with a first event of premature MI and 519 matched control patients. One year after the event, 61 patients and 205 control patients were recalled for the follow-up study. Blood sampling was performed during the acute phase and after one year. The risk for MI in 894TT was 1.992 (95% confidence interval [CI], 1.131 to 3.485), p < 0.05 versus GG+GT; 2.038 (95% CI, 1.125 to 3.695), p < 0.05 versus GG; and 2.009 (95% CI, 1.106 to 3.651), p < 0.05 versus GT. During the acute phase, vWF was higher in GT+TT (121.02 +/- 5.47%) versus GG (84.6 +/- 7.1%, p < 0.01), an effect persisting after one year (90.4 +/- 3.8 vs. 73.1 +/- 4.6%, p < 0.01). During the acute phase, GT+TT had higher ox-LDL and IL-6 (131.2 +/- 6.4 IU/l and 8.5 +/- 0.7 pg/ml) compared with GG (101.7 +/- 9.64 IU/l and 6.2 +/- 0.8 pg/ml, p < 0.05 for both), but no difference was found at one year. G894T polymorphism on the eNOS gene increases the risk for premature MI and modifies the response of vascular endothelium during the acute phase of MI by affecting the release of vWF, IL-6, and oxidative stress status, an effect diminished one year after the event.

Associations of the Angiotensin II Type 1 Receptor A 1166 C and the Endothelial NO Synthase G 894 T Gene Polymorphisms With Silent Subcortical White Matter Lesions in Essential Hypertension

Silent white matter lesions (WMLs) may represent early target organ damage of the brain in patients with hypertension. Because these lesions may have a genetic background, we assessed the associations between polymorphisms of the renin-angiotensin system and the endothelial NO synthase (NOS3) genes and silent WMLs. Ninety-three hypertensive individuals were studied. MRI of the brain was performed to obtain estimates of the total volume of subcortical and the extent of periventricular WMLs. Patients were genotyped for the angiotensinogen (M235T), the angiotensin-converting enzyme (insertion/deletion [I/D]), the angiotensin II type 1 receptor (AGTR1 A1166C), and the NOS3 (G894T) genes. A linear regression model was used to assess the relationship of these gene polymorphisms with both subtypes of WMLs. When adjusted for age, diabetes mellitus, and blood pressure, subcortical WML volume was lowest in the presence of 1 or 2 AGTR1 C alleles (unstandardized beta, -38.8 [95% CI, -66.1 to -11.4] and -112.6 [CI, -188.9 to -36.4], respectively), whereas it was highest in the presence of an NOS3 T allele (31.1[corrected] [CI, 3.6 to 58.4]). No interaction between these polymorphisms on WMLs could be demonstrated. No associations were present with the other polymorphisms, either with subcortical or periventricular lesions. We found the AGTR1 A1166C as well as the NOS3 G894T polymorphisms to be associated with silent WMLs in the subcortical area.

Relevance of the NOS3 T–786C and G894T variants for cholinergic and adrenergic coronary vasomotor responses in man

We investigated the impact of the -786C allele at the promoter and the 894T allele in exon 7 of the gene encoding the endothelial nitric oxide synthase (NOS3) on coronary vasomotor responses to exogenous and endogenous stimuli. In 47 individuals undergoing coronary angiography for chest pain, but without significant stenosis in the left anterior descending artery (LAD), nitroglycerine and acetylcholine were infused intracoronarily, and a cold pressor test (CPT) was performed. Coronary blood flow (CBF) in the LAD was calculated from quantitative coronary angiography and intracoronary Doppler measurements. Aortic and coronary sinus lactate levels were determined in 18 individuals. To analyze the impact of NOS3 genotypes, a logistic regression model was used. In response to acetylcholine (p = 0.002) and CPT (p = 0.015) CBF reduction was associated with homocygosity for the -786C allele. Myocardial lactate uptake was reversed into net lactate production in CC homocygotes. No independent effects of the G894T polymorphism were observed in the present study. Haplotype analysis revealed a significant linkage disequilibrium between both polymorphisms (p < 0.001). Our findings suggest a pathophysiologically relevant role for the T-786C polymorphism in human coronary vasomotion. The observed linkage disequilibrium between both NOS3 genotypes deserves further research in future studies.

Effects of genetic polymorphism G894T on endothelial nitric oxide synthase, on endothelial function, thrombosis/fibrinolysis system and inflammatory process, in young myocardial infarction survivors

Genetic polymorphism G894T on endothelial nitric oxide synthase (eNOS), has been associated with increased risk of myocardial infarction (MI). However, its effects on endothelial function, thrombosis/fibrinolysis system and inflammatory process remain unknown. We investigated the effect of G894T polymorphism on endothelial function, thrombosis/fibrinolysis and inflammatory markers in young MI survivors. This study enrolled 60 young patients with a history of premature MI (mean age 45.2±4.2 years). All patients were in stable clinical condition for at least one year before recruitment. Endothelial function was evaluated in the forearm using venous occlusion strain-gauge plethysmography. Endothelium dependent dilation (EDD) and endothelium independent dilation (EID) were expressed as the %change of forearm blood flow from rest to the maximum flow during reactive hyperemia or after sublingual nitroglycerin administration respectively. The G894T polymorphism on eNOS gene was determined by polymerase chain reaction (PCR), while plasma levels of plasminogen activator inhibitor (PAI-1), vonWillebrand factor (vWF) and interleukin 1b (IL-1b) were measured with ELISA. Patients were divided into groups according to genotype. Twenty patients were G homozygotes, 31 were heterozygotes and 9 were T homozygotes. EDD was significantly higher in GG (113.1±14.5) compared GT (39.8±5.2%) or TT(41.1±3.3%). VWF was significantly higher in GT (65.5±2.5%) or TT(57.7±3.2) compared to GG (50.4±3.5%,p<0.05 for both). Carriers of the T allele had significantly lower EDD (p<0.01) and higher levels of vWF (p<0.05) compared to GG. Plasma PAI-1 and IL-1b were not significantly different between TT+GT (35.4±4.9ng/ml and 0.86±0.12 pg/ml) and GG (37.2±6.6 mg/dl and 0.84±0.13pg/ml respectively, p=NS for both). Carriers of the T allele have blunted endothelial function, and higher levels of von Willebrand factor one year after an incident of premature myocardial infarction. Therefore, G894T polymorphism on eNOS gene may affect endothelial function and thrombosis, in patients with premature myocardial infarction.

Synergistic effect between eNOS gene G894T and GNB3 gene C825T polymorphisms in patients with essential hypertension

Synergistic effect between eNOS gene G894T and GNB3 gene C825T polymorphisms in patients with essential hypertension

Genetic polymorphisms G894T on the eNOS gene is associated with endothelial function and vWF levels in premature myocardial infarction survivors

Background Genetic polymorphism G894T on endothelial nitric oxide synthase (eNOS) gene has been associated with endothelial dysfunction in young smokers, but its role in the pathogenesis of MI is obscure. We examined the effect of G894T polymorphism on endothelial function, on markers of endothelial cells injury and activation such as von Willebrand factor (vWF) and on serum levels of proinflammatory cytokines such as interleukins 6 (IL-6) and 1b (IL-1b), in young myocardial infarction (MI) survivors. Methods The study population consisted of 56 patients with a history of premature MI. The forearm blood flow (FBF) was measured by using strain-gauge plethysmography during reactive hyperemia and after sublingual administration of nitroglycerin. G894T polymorphism was determined by polymerase chain reaction (PCR), while plasma vWF and serum IL1b and IL-6 levels were determined with ELISA. Results There was no significant difference in resting FBF and in the responses to nitroglycerin between the genotypes. However, the presence of T allele (GT + TT, n = 35) was associated with decreased FBF during reactive hyperemia (10.23 ± 0.70 ml/100ml tissue/min) and decreased forearm vasodilatory response to reactive hyperemia (54.28 ± 4.81%) compared to GG (13.82 ± 0.92 ml/100 ml tissue/min and 83.92 ± 9.89% respectively, p < 0.01 for both). Carriers of the T allele had also higher levels of vWF (79.66 ± 5.56%) compared to GG (60.94 ± 5.27% p < 0.05). However, no significant difference was observed in IL-1b and IL-6 serum levels between the genotypes ( p = ns for both). Conclusions The presence of 894T allele on eNOS gene is associated with impaired endothelial function and higher levels of von Willebrand factor in relatively young patients with myocardial infarction. This finding implies that genetic polymorphism G894T on eNOS may affect endothelial function in patients with a history of premature myocardial infarction.

W02-P-014 G894T polymorphism on endothelial nitric oxide synthase gene as a risk factor for premature myocardial infarction in young smokers

W02-P-014 G894T polymorphism on endothelial nitric oxide synthase gene as a risk factor for premature myocardial infarction in young smokers

Genotype-Dependent Expression of Endothelial Nitric Oxide Synthase (eNOS) and Its Regulatory Proteins in Cultured Endothelial Cells

DNA polymorphisms in endothelial nitric oxide synthase (eNOS) gene have been shown to be associated with constitutive eNOS expression and coronary artery disease (CAD). In the present study we explored the hypothesis whether genotype-dependent effects can be maintained in vitro during replication, or the effect is conditional on in vivo biological environments. Human umbilical vein endothelial cells (HUVEC) were collected and cultured from 89 normal deliveries of Mexican Americans. The cells were treated with or without cigarette smoking extracts (CSE) and genotypes of eNOS polymorphisms were determined by PCR. We measured the levels of eNOS by ELISA and its binding proteins including heat-shock protein 90 (Hsp-90) and caveolin-1 by Western blotting. The rare C allele for the promoter T786C polymorphism (0.2), and the rare 4 x 27-bp repeat allele in the intron 4 (0.30) were different from those reported in other populations. Yet, the rare T allele in the exon 7 (G894T polymorphism) was similar as others. After four passages in vitro, both the intron 4 and promoter polymorphisms maintained significant effects on eNOS mRNA levels in HUVECs (P < 0.05). However, the effects on eNOS protein and enzyme activity were less consistent. Although primary smokers had significantly lower eNOS protein levels (P < 0.05), the in vitro CSE treatment on cultured HUVECs only resulted in a significant reduction in NO levels as measured by the stable metabolites of nitrite/nitrate (P < 0.001). Neither Hsp-90 nor caveolin-1--important eNOS regulators--appears to mediate the genotypesmoking effects on eNOS expression although HUVECs did produce more Hsp-90 when exposed to CSE. Our study demonstrates that endothelial cells maintain genotype-dependent expression even after the deprivation of in vivo environment. However, the cigarette smoking-genotype interaction may require such in vivo conditions to be manifested.

Influence of G894T eNOS gene polymorphism on postoperative hemodynamics after cardiac surgery with cardiopulmonary bypass

Objectives: Differences in vascular reactivity have been associated to variable NO release due to the G894T polymorphism of the eNOS gene. Carriers of the 894T allele are known to have enhanced vascular responsivness to α-adrenergic stimulation which may have an effect on postoperative hemodynamics after cardiac surgery. Thus we hypothesized that the G894T gene polymorphism should influence perioperative hemodynamics and vascular resistance in patients undergoing cardiac surgery.

The G894T polymorphism on endothelial nitric oxide synthase gene is associated with premature coronary artery disease in a Turkish population

Introduction The aim of the present study was to investigate the association between premature coronary artery disease and Glu298Asp polymorphism of the endothelial nitric oxide synthase gene. Materials and methods The eNOS gene polymorphism was analysed in 115 (mean age, 48.1±7.9 years) Turkish patients with a diagnosis of premature coronary artery disease and 83 (mean age, 44.6±1.4 years) control subjects. The Glu298Asp polymorphism of the endothelial nitric oxide synthase gene was determined by polymerase chain reaction and restriction fragment length polymorphism. Results The patients group showed an increase in the frequency of the T allele compared to controls (0.456 versus 0.169, p=0.0001). There was a significant association between the TT genotype and premature coronary artery disease [eNOS TT vs. TG and GG; OR=17.000 (CI 95% 3.952–73.125, p=0.0001)]. The eNOS T/G genotypes were not associated with the number of affected vessels ( p>0.05). In addition, the family history of premature coronary artery disease, smoking, diabetes, obesity, dyslipidemia and eNOS TT genotype were independent risk factors of coronary artery disease. The patients with eNOS TT genotype had 15 fold risk of coronary artery disease compared with the control group [OR=15.356(CI 95% 3.262–77.289, p=0.001)]. Conclusions These results suggest that premature coronary artery disease is associated with the Glu298Asp polymorphism of the endothelial nitric oxide synthase gene in our population.

Endothelial nitric oxide synthase gene polymorphism and ischemic heart disease

Background Ischemic heart disease (IHD), the leading cause of death worldwide, is a multifactorial disease arising from the complex interplay of genetic and environmental factors. There is considerable evidence that nitric oxide (NO) plays an important role in protecting against atherosclerosis, the process underlying IHD. Endothelial NO is synthesized from the amino acid l-arginine by the endothelial isoform of NO synthase (eNOS). Thus, polymorphisms of the eNOS gene, by altering production of NO within the vascular endothelium, are potential risk factors for IHD. Several groups have investigated the role of the G894T polymorphism of the eNOS gene in IHD by using case-control association studies; however, its role is unclear because of contradictory results from these studies. We applied family-based association tests to investigate the role of this polymorphism in IHD in a well-defined Irish population. Methods A total of 1023 individuals from 388 families (discordant sibships and parent-offspring trios) were recruited. Linkage disequilibrium between the polymorphism and IHD was tested for by using the combined transmission disequilibrium test/sib–transmission disequilibrium test and pedigree disequilibrium test. Results Both the combined transmission disequilibrium test/sib–transmission disequilibrium test and pedigree disequilibrium test analyses found no statistically significant excess transmission of either allele to affected individuals ( P = .57 and P = .38, respectively). Conclusions Using robust family-based association tests specifically designed for the study of complex diseases, we found no evidence that the G894T polymorphism of the eNOS gene has a significant role in the development of IHD in our population.

Risk of coronary artery disease associated with polymorphism of the cytochrome P450 epoxygenase CYP2J2.

Cytochrome P450 (CYP) 2J2 is expressed in the vascular endothelium and metabolizes arachidonic acid to biologically active epoxyeicosatrienoic acids (EETs). The EETs are potent endogenous vasodilators and inhibitors of vascular inflammation. However, it is not known whether genetic polymorphisms of CYP2J2 are associated with increased cardiovascular risks. All 9 exons of the CYP2J2 gene and its proximal promoter were sequenced in 132 patients to identify potential variants. Functional consequence of a single nucleotide polymorphism (SNP) in the promoter of CYP2J2 was further evaluated by use of transcription factor-binding and reporter assays. A total of 17 polymorphisms were identified. One of the most relevant polymorphisms in terms of frequency and functional importance is located at -50 (G-50T) in the proximal promoter of CYP2J2. Screening of 289 patients with coronary artery disease and 255 control subjects revealed 77 individuals with the G-50T SNP (17.3% of coronary artery disease patients, 10.6% of control subjects; P=0.026). The association of the G-50T polymorphism remained significant after adjustment for age, gender, and conventional cardiovascular risk factors (OR, 2.23; 95% CI, 1.04 to 4.79). The G-50T mutation resulted in the loss of binding of the Sp1 transcription factor to the CYP2J2 promoter and resulted in a 48.1+/-2.4% decrease in CYP2J2 promoter activity (P<0.01). Plasma concentrations of stable EET metabolites were significantly lower in individuals with the G-50T SNP. A functionally relevant polymorphism of the CYP2J2 gene is independently associated with an increased risk of coronary artery disease.

Evidence for association between endothelial nitric oxide synthase gene polymorphism (G894T) and inflammatory markers: The ATTICA study

Background We evaluated the effect of the point mutation of guanine to thymine at nucleotide position 894 (G894T) of the endothelial nitric oxide synthase (eNOS) gene on inflammatory and oxidative stress markers. Methods We studied genetic information from 270 men (18–87 years old) and 325 women (18–89 years old). Participants without any clinical evidence of cardiovascular or other atherosclerotic disease were randomly selected from the general population according to the age–sex distribution of Athens greater area. Genomic DNA was extracted from 2 to 5 mL of fresh or frozen whole blood using standard methods. Results The DNA analysis showed that 10.6% of the participants were Asp-homozygotes (Asp/Asp), 40% heterozygotes (Asp/Glu) and 49.4% Glu-homozygotes (Glu/Glu). Compared to Asp/Glu and Glu/Glu, Asp/Asp had higher levels of fibrinogen (332 ± 46 or 329 ± 33 vs 319 ± 29 mg/dL, P = .029), white blood cells (6.9 ± 0.6 or 6.5 ± 0.3 vs 6.1 ± 0.9 × 10 3 counts, P = .044), and oxidized low-density lipoprotein cholesterol (68 ± 21 or 61 ± 22 vs 59 ± 20 mg/dL, P = .039), after controlling for several potential confounders. An insignificant association was found between homocysteine ( P = .08), C-reactive protein ( P = .096), and the distribution of G894T polymorphism ( P < .1). No association between the distribution of the polymorphism and hypertension status of the participants was observed. Conclusions Our results imply that G894T polymorphism of the endothelial nitric oxide synthase gene is associated with elevated levels of inflammatory and oxidative stress markers, which may partially explain the increased prevalence of G894T polymorphism among patients with cardiovascular disease.