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Renin-Angiotensin System Genes Polymorphisms and Essential Hypertension in Burkina Faso, West Africa. Int J Hypertens 2015; 2015:979631. [PMID: 26351579 PMCID: PMC4553326 DOI: 10.1155/2015/979631] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2015] [Accepted: 07/08/2015] [Indexed: 11/18/2022] Open
Abstract
Objective. This study aimed to investigate the association between three polymorphisms of renin-angiotensin system and the essential hypertension in the population of Burkina Faso. Methodology. This was a case-control study including 202 cases and 204 matched controls subjects. The polymorphisms were identified by a classical and a real-time PCR. Results. The AGT 235M/T and AT1R 1166A/C polymorphisms were not associated with the hypertension while the genotype frequencies of the ACE I/D polymorphism between patients and controls (DD: 66.83% and 35.78%, ID: 28.22% and 50.98%, II: 4.95% and 13.24%, resp.) were significantly different (p < 10−4). The genotype DD of ACE gene (OR = 3.40, p < 0.0001), the increasing age (OR = 3.83, p < 0.0001), obesity (OR = 4.84, p < 0.0001), dyslipidemia (OR = 3.43, p = 0.021), and alcohol intake (OR = 2.76, p < 0.0001) were identified as the independent risk factors for hypertension by multinomial logistic regression. Conclusion. The DD genotype of the ACE gene is involved in susceptibility to hypertension. Further investigations are needed to better monitor and provide individualized care for hypertensive patients.
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Renin-angiotensin system polymorphisms in relation to hypertension status and obesity in a Tunisian population. Mol Biol Rep 2011; 39:4059-65. [PMID: 21779803 DOI: 10.1007/s11033-011-1187-2] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2011] [Accepted: 07/11/2011] [Indexed: 10/18/2022]
Abstract
Essential hypertension (HTA) is the clinical expression of a disordered interaction between the genetic, physiological, and biochemical systems that under usual conditions maintain cardiovascular homeostasis. We studied the effects of the angiotensinogen M235T, angiotensin converting enzyme insertion/deletion (ACE I/D), and angiotensin II receptor 1 (AT1R) A1166C gene polymorphisms on the risk of HTA and to evaluate the relationship between these polymorphisms and obesity. We performed AGT, ACE and AGTR genotyping in 142 hypertensive patients and 191 control subjects using PCR-RFLP methods and PCR, respectively. The three polymorphisms were significantly associated with HTA. Individuals carrying the mutated TT of AGT, DD of ACE and CC of AT1R genotypes had an 1.67 (P = 0.032), 3.09 (P < 0.001) and 3.45 (P < 0.001)-fold increased risk of HTA. After adjustment for sex, smoking, diabetes, dyslipidemia, BMI, triglycerides and DD, TT and CC genotypes, BMI was independent risk factor of HTA (OR = 3.14; P < 0.001). An association of BMI with ACE gene polymorphism (P = 0.035), whereas no association with AGT and AT1R gene polymorphisms was obtained. The proportion of hypertensives is as high as 21.8 and 13.4% in the overweight and the obese DD group. The present study implies that the genotyping for the variants of RAS gene could in the future become an important part of the clinical process of risk identification for HTA.
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Zakrzewski-Jakubiak M, de Denus S, Dubé MP, Bélanger F, White M, Turgeon J. Ten renin-angiotensin system-related gene polymorphisms in maximally treated Canadian Caucasian patients with heart failure. Br J Clin Pharmacol 2008; 65:742-51. [PMID: 18279468 PMCID: PMC2432486 DOI: 10.1111/j.1365-2125.2007.03091.x] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2007] [Accepted: 10/10/2007] [Indexed: 02/03/2023] Open
Abstract
WHAT IS ALREADY KNOWN ABOUT THIS SUBJECT The progression and pharmacological response of heart failure-affected patients are subject to interindividual variability. It is also acknowledged that the genotype frequency of certain gene polymorphisms varies across different ethnic groups and that a difference in gene polymorphism frequencies between healthy and heart failure patients seems to exist. WHAT THIS STUDY ADDS This study investigated associations between 10 gene polymorphisms of RAAS-related genes with an individual's susceptibility to heart failure. Our data suggest that the angiotensinogen (AGT) 235 single nucleotide polymorphism (SNP) may be associated with heart failure in our population and that the AGT(M174)-AGT(T235) haplotype, as well as the AGT/angiotensin-converting enzyme (ACE) gene combination, may play an important role in disease predisposition. AIMS Racial differences in survival outcomes point towards a genetic role in the pathophysiology of heart failure. Furthermore, contemporary evidence links genetics to heart failure (HF) predisposition. We tested for a difference in prevalence of 10 renin-angiotensin-aldosterone system (RAAS)-related gene polymorphisms between a homogenous population of HF patients and healthy controls. METHODS One hundred and eleven healthy volunteers and 58 HF patients were included in this study. The healthy control group consisted of males aged between 18 and 35 years old. The HF group consisted of patients (89.7% male) who were 63.8 +/- 7.9 years old, were in New York Heart Association (NYHA) class II-III and had a documented left ventricular ejection fraction (LVEF) CONCLUSIONS This study demonstrates that the SNPs of AGT may be associated with HF in our population and that the AGT/ACE gene combination may play an important role in disease predisposition.
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Affiliation(s)
| | - Simon de Denus
- Université de MontréalMontréal, Canada
- Montreal Heart InstituteMontréal, Canada
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Abstract
This review explores the emergence of Comparative Medicine in the late 19th Century as 'the medicine of the future', its failure to realise these expectations during the 20th century as it became increasingly equated with laboratory animal models of human disease, and explains why there is now an unprecedented opportunity for this latent potential to be fully realised. Comparative medicine no longer rests on apparent similarities between disease mechanisms in different species but on the rapidly maturing ability to relate these similarities to a remarkably rich shared genetic heritage. In the United Kingdom, the creation of the new Medical Research Council Comparative Clinical Science Panel, once securely funded, will provide the infrastructure and strategic focus to foster comparative clinical research, encouraging collaboration between veterinary and human medicine and between investigators in institutes and in practice. This will generate the necessary evidence base for veterinary practice, raise the standard of veterinary research, broaden the horizons of human medicine and create real opportunities for veterinary surgeons to reconcile research with practice. The review explores the broad scope of the science which will flourish in this new environment and examines specific areas in greater depth as examples, notably multifactorial disease such as hypertension and diarrhoea, also aspects of comparative endocrinology and oncology, with emphasis on the growing power conferred by comparative molecular genetics.
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Affiliation(s)
- A R Michell
- Department of Biochemical Pharmacology, Harvey Research Institute, St. Bartholomew's Hospital, Charterhouse Square, London EC1M 6BQ, UK.
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Bleumink GS, Schut AFC, Sturkenboom MCJM, Deckers JW, van Duijn CM, Stricker BHC. Genetic polymorphisms and heart failure. Genet Med 2005; 6:465-74. [PMID: 15545741 DOI: 10.1097/01.gim.0000144061.70494.95] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
Heart failure is a complex clinical syndrome. There is evidence for a genetic contribution to the pathophysiology of heart failure. Considering the fundamental role of neurohormonal factors in the pathophysiology and progression of cardiac dysfunction and hypertrophy, variants of genes involved in this system are logical candidate genes in heart failure. In this report, genetic polymorphisms of the major neurohormonal systems in heart failure will be discussed. Studies on polymorphisms of the renin-angiotensin-aldosterone system (RAAS), adrenergic receptor polymorphisms, endothelin (receptor) polymorphisms, and a group of miscellaneous polymorphisms that may be involved in the development or phenotypic expression of heart failure will be reviewed. Research on left ventricular hypertrophy is also included. The majority of genetic association studies focused on the ACE I/D polymorphism. Initial genetic associations have often been difficult to replicate, mainly due to problems in study design and lack of power. Promising results have been obtained with genetic polymorphisms of the RAAS and sympathetic system. Considering the evidence so far, a modifying role for these polymorphisms seems more likely than a role of these variants as susceptibility genes. Besides the need for larger studies to examine the effects of single nucleotide polymorphisms and haplotypes, future studies also need to focus on the complexity of these systems and study gene-gene interactions and gene-environment interactions.
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Affiliation(s)
- Gysèle S Bleumink
- Department of Epidemiology and Biostatistics, Erasmus Medical Center, Rotterdam, The Netherlands
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Mondry A, Loh M, Liu P, Zhu AL, Nagel M. Polymorphisms of the insertion / deletion ACE and M235T AGT genes and hypertension: surprising new findings and meta-analysis of data. BMC Nephrol 2005; 6:1. [PMID: 15642127 PMCID: PMC546009 DOI: 10.1186/1471-2369-6-1] [Citation(s) in RCA: 95] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2004] [Accepted: 01/11/2005] [Indexed: 02/02/2023] Open
Abstract
Background Essential hypertension is a common, polygenic, complex disorder resulting from interaction of several genes with each other and with environmental factors such as obesity, dietary salt intake, and alcohol consumption. Since the underlying genetic pathways remain elusive, currently most studies focus on the genes coding for proteins that regulate blood pressure as their physiological role makes them prime suspects. The present study examines how polymorphisms of the insertion/deletion (I/D) ACE and M235T AGT genes account for presence and severity of hypertension, and embeds the data in a meta-analysis of relevant studies. Methods The I/D polymorphisms of the ACE and M235T polymorphisms of the AGT genes were determined by RFLP (restriction fragment length polymorphism) and restriction analysis in 638 hypertensive patients and 720 normotensive local blood donors in Weisswasser, Germany. Severity of hypertension was estimated by the number of antihypertensive drugs used. Results No difference was observed in the allele frequencies and genotype distributions of ACE gene polymorphisms between the two groups, whereas AGT TT homozygotes were more frequent in controls (4.6% vs. 2.7%, P = .08). This became significant (p = 0.035) in women only. AGT TT genotype was associated with a 48% decrease in the risk of having hypertension (odds ratio: 0.52; 95% CI, 0.28 to 0.96), and this risk decreased more significantly in women (odds ratio: 0.28; 95% CI, 0.1 to 0.78). The meta-analysis showed a pooled odds ratio for hypertension of 1.21 (TT vs. MM, 95% CI: 1.11 to 1.32) in Caucasians. No correlation was found between severity of hypertension and a specific genotype. Conclusion The ACE I/D polymorphism does not contribute to the presence and severity of essential hypertension, while the AGT M235T TT genotype confers a significantly decreased risk for the development of hypertension in the population studied here. This contrasts to the findings of meta-analyses, whereby the T allele is associated with increased risk for hypertension.
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Affiliation(s)
- Adrian Mondry
- Bioinformatics Institute, 30 Biopolis Street, #07-01 Matrix Building, 138671 Singapore
| | - Marie Loh
- Bioinformatics Institute, 30 Biopolis Street, #07-01 Matrix Building, 138671 Singapore
| | - Pengbo Liu
- Bioinformatics Institute, 30 Biopolis Street, #07-01 Matrix Building, 138671 Singapore
| | - Ai- Ling Zhu
- Bioinformatics Institute, 30 Biopolis Street, #07-01 Matrix Building, 138671 Singapore
| | - Mato Nagel
- MolDiag Ag, Albert- Schweitzer- Ring 32, 02943 Weisswasser, Germany
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Sunder-Plassmann G, Kittler H, Eberle C, Hirschl MM, Woisetschläger C, Derhaschnig U, Laggner AN, Hörl WH, Födinger M. Angiotensin converting enzyme DD genotype is associated with hypertensive crisis. Crit Care Med 2002; 30:2236-41. [PMID: 12394950 DOI: 10.1097/00003246-200210000-00010] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
OBJECTIVE The genetic background of hypertensive crisis is unknown. We examined the association of polymorphisms in genes involved in the renin-angiotensin-aldosterone-system with hypertensive crisis. DESIGN Population-based case-control study. SETTING Emergency department at a tertiary care university hospital. PATIENTS A total of 182 patients with essential hypertension who were admitted to an emergency department for treatment of hypertensive crisis and 182 age- and sex-matched healthy individuals. INTERVENTIONS None. MEASUREMENTS Analysis of polymorphisms in genes coding for angiotensinogen (AJT 704T-->C), angiotensin II receptor 1 (AGTR1 1166A-->C), renin (REN 2646G-->A), renin-binding protein (RENBP 61T-->C), alpha-adducin (ADD1 1378G-->T), beta-2-adrenergic receptor (ADRB2 46A-->G, 79C-->G), and angiotensin I converting enzyme (ACE I/D) was performed by polymerase chain reaction and restriction fragment length polymorphism analysis. MAIN RESULTS Among patients, the ACE I/D polymorphism showed a deviation from Hardy-Weinberg equilibrium (p =.01). In controls, all polymorphisms were in the Hardy-Weinberg equilibrium. The frequency of the DD genotype was increased in patients (n = 70, 38.5%) vs. controls (n = 51; 28.0%;p =.03; odds ratio, 1.61; 95% confidence interval, 1.03-2.50), which was due to the DD genotype in 40 male patients (44%) vs. 23 in male controls (25.3%;p =.004; odds ratio, 3.48; 95% confidence interval, 1.47-8.30). There were no differences in genotype distributions among other polymorphisms. CONCLUSION We demonstrate a possible association of the DD genotype with hypertensive crisis in men.
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Julve R, Chaves FJ, Rovira E, Pascual JM, Miralles A, Armengod ME, Redon J. Polymorphism insertion/deletion of the ACE gene and ambulatory blood pressure circadian variability in essential hypertension. Blood Press Monit 2001; 6:27-32. [PMID: 11248758 DOI: 10.1097/00126097-200102000-00005] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVE The objective of the present study was to analyze the influence of the insertion/deletion (I/D) polymorphism of the angiotensin-converting enzyme on ambulatory blood pressure values and circadian variability in untreated patients with hypertension. MATERIAL AND METHODS Ninety-nine essential hypertensive patients, less than 50 years old (mean age 39.5+/-7.0 years), previously untreated with antihypertensive drugs were included. Twenty-four hour ambulatory blood pressure monitoring (ABPM) was performed with a Spacelabs (90202 and 90207) monitor, during a regular working day in unrestricted ambulatory conditions. The I/D polymorphism of the ACE was determined by PCR. RESULTS The distributions of genotypes were in Hardy-Weinberg equilibrium: I=17 (17%), ID=41 (41.5%), DD=41 (41.5%). No significant differences were present among the groups in terms of age, sex, and biochemical and lipid profiles. The average of 24-h ambulatory blood pressure was slightly higher in patients with the DD genotype as compared with patients with the II and ID genotypes. This was the result of higher nighttime blood pressure values, because no differences in blood pressure were observed during daytime. The systolic blood pressure (SBP) day:night ratio, as an estimate of circadian variability, was significantly lower in subjects homozygous for the D allele than it was in patients carrying the I allele (1.13+/-0.09 vs. 1.17+/-0.08, P=0.014). The subjects in the lowest tertile of the SBP day:night ratio, exhibited a higher frequency of the D allele when compared with those in the middle tertile (0.74 vs. 0.59, P<0.05) or with those in the highest tertile (0.74 vs. 0.54, P<0.01). By using two-way ANOVA with repeated measures, significant differences in SBP variation over time were observed when comparing homozygous for the D allele with subjects carrying the I allele (F=2.11, P=0.002). CONCLUSIONS Among the genotypes of the I/D polymorphism, subjects carrying DD genotype showed a blunted decline of the physiological nocturnal fall of blood pressure that was significant for SBP.
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Affiliation(s)
- R Julve
- Internal Medicine, Hospital of Sagunto, University of Valencia, Spain
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Padmanabhan N, Padmanabhan S, Connell JM. Genetic basis of cardiovascular disease--the renin-angiotensin-aldosterone system as a paradigm. J Renin Angiotensin Aldosterone Syst 2000; 1:316-24. [PMID: 11967817 DOI: 10.3317/jraas.2000.060] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
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10
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Abstract
Essential hypertension is a complex disease influenced by different genetic and environmental factors. The renin-angiotensin system (RAS) is implicated in blood pressure regulation. Angiotensinogen (AGT) is the precursor of the biologically active angiotensin II (Ang II). Initial studies on hypertensive siblings and case-control studies indicated the important role of the angiotensinogen gene (AGT) for the predisposition to essential hypertension, preeclampsia and obesity-related hypertension. Recently, different AGT polymorphisms had been identified and analyzed in case-control studies. The aim of present studies is the analysis of potentially functional AGT variants (C-532T, G-6A), which might be responsible for the regulation of gene expression and therefore AGT generation. The A-6 allele is in complete linkage disequilibrium with the T235 allele and is associated with higher AGT expression in vitro. Segregation linkage analysis demonstrated that the C-532T polymorphism influences plasma AGT variability more significantly than the G-6A variant. Since the C-532T polymorphism is located within a AP-2 consensus element, functional promoter analyses are required. The understanding of the molecular basis of RAS in essential hypertension may provide us with new and more specific pharmacological agents and perhaps the ability to individualize antihypertensive treatment.
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Affiliation(s)
- E Brand
- Medizinische Klinik IV, Endokrinologie und Nephrologie, Universitätsklinikum Benjamin Franklin, Freien Universität Berlin
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11
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Wang WY, Glenn CL, Zhang W, Benjafield AV, Nyholt DR, Morris BJ. Exclusion of angiotensinogen gene in molecular basis of human hypertension: sibpair linkage and association analyses in Australian anglo-caucasians. AMERICAN JOURNAL OF MEDICAL GENETICS 1999; 87:53-60. [PMID: 10528248 DOI: 10.1002/(sici)1096-8628(19991105)87:1<53::aid-ajmg11>3.0.co;2-i] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
Linkage with essential hypertension has been claimed for a microsatellite marker near the angiotensinogen gene (AGT; chromosome 1q42), as has association for the AGT variants M235T, G(-6)A and A(-20)C. To more rigorously evaluate AGT as a candidate gene for hypertension we performed sibpair analysis with multiple microsatellite markers surrounding this locus and using more sophisticated analysis programs. We also performed an association study of the AGT variants in unrelated subjects with a strong family history (two affected parents). For the linkage study, single and multiplex polymerase chain reaction (PCRs) and automated genescan analysis were conducted on DNA from 175 Australian Anglo-Celtic Caucasian hypertensives for the following markers: D1S2880-(2.1 cM)-D1S213-(2.8 cM)-D1S251-(6.5 cM)-AGT-(2.0 cM) -D1S235. Statistical evaluation of genotype data by nonparametric methods resulted in the following scores: Single-point analysis - SPLINK, P > 0.18; APM method, P > 0.25; ASPEX, MLOD < 0.28; SIB-PAIR, P > 0. 24; Multipoint analysis - MAPMAKER/SIBS, MLOD < 0.24; GENEHUNTER, P > 0.35. Exclusion scores of Lod -4.1 to -5.1 were obtained for these markers using MAPMAKER/SIBS for a lambda(s) of 1.6. The association study of G(-6)A, A(-20)C and M235T variants in 111 hypertensives with strong family history and 190 normotensives with no family history showed significant linkage disequilibrium between particular haplotypes, but we could find no association with hypertension. The present study therefore excludes AGT in the etiology of hypertension, at least in the population of Australian Anglo-Celtic Caucasians studied.
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Affiliation(s)
- W Y Wang
- Hypertension Gene Laboratory, Department of Physiology and Institute for Biomedical Research, The University of Sydney, Sydney, New South Wales, Australia
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Winkelmann BR, Russ AP, Nauck M, Klein B, Böhm BO, Maier V, Zotz R, Matheis G, Wolf A, Wieland H, Gross W, Galton DJ, März W. Angiotensinogen M235T polymorphism is associated with plasma angiotensinogen and cardiovascular disease. Am Heart J 1999; 137:698-705. [PMID: 10097233 DOI: 10.1016/s0002-8703(99)70226-7] [Citation(s) in RCA: 87] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
BACKGROUND Genes encoding components of the renin-angiotensin system have been associated with elevated blood pressure (BP) and an increased risk of coronary artery disease. To explore the role of the angiotensinogen (AGT) gene in coronary atherosclerosis and thrombosis, we studied the effect of the AGT M235T gene variant on plasma AGT levels and BP in patients with coronary artery disease and in the subgroup of survivors of myocardial infarction as compared with angiographically defined control subjects. METHODS AND RESULTS This was a case-control study of 301 white male subjects examined at Frankfurt University medical center. Plasma AGT levels increased stepwise according to the number of T235 alleles present (no T235 allele, 14.8 +/- 3.9 nmol/L; 1 allele, 15.7 +/- 5.1 nmol/L; 2 alleles, 17.3 +/- 4.7 nmol/L; P =.006). In a multivariate model, circulating AGT emerged as the most important predictor of diastolic pressure (P =.001). In addition, AGT M235T gene polymorphism remained a significant predictor of diastolic BP in a multivariate model adjusted for age, body mass index, fasting glucose, apolipoprotein B, presence of coronary artery disease, and treatment with antihypertensive agents ( P <.05). Finally, homozygosity for T235 was associated with increased univariate risk of coronary artery disease and myocardial infarction (odds ratio estimates 1.5; 95% confidence intervals 1.1 to 2.1, P =.03, and 1.0 to 2.1, P =.05, respectively). CONCLUSIONS The significant relations observed between the AGT M235T variant, its protein product, and the cardiovascular disease phenotypes provide evidence for a possible role of elevated circulating AGT in the pathogenesis of coronary artery disease.
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Affiliation(s)
- B R Winkelmann
- Department of Cardiology, Ludwigshafen Heart Center, Frankfurt, Germany
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Schorr U, Blaschke K, Beige J, Distler A, Sharma AM. Angiotensinogen M235T variant and salt sensitivity in young normotensive Caucasians. J Hypertens 1999; 17:475-9. [PMID: 10404948 DOI: 10.1097/00004872-199917040-00004] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
BACKGROUND AND AIMS A single-nucleotide variant of the angiotensinogen gene (AGT 235T) has been associated with essential hypertension and increased plasma levels of angiotensinogen. This variant may also serve as a genetic marker for the increased blood pressure response to dietary salt intake, but the relationship between AGT genotype and salt sensitivity has not been studied until now. We therefore examined the relationship between the AGT 235T genotype and the blood pressure response to short-term dietary salt restriction in young normotensive men. SUBJECTS AND METHODS A total of 187 young normotensive men were characterized for family history of hypertension, salt sensitivity, plasma parameters of the renin-angiotensin system under high- and low-salt diets, and the AGT 235T genotype. RESULTS While the T allele was significantly associated with a positive family history of hypertension (chi2 = 7.0; P< 0.03) and higher plasma angiotensinogen levels (P< 0.015) and renin activity (P < 0.037), blood pressure under both diets was not significantly affected by the AGT genotype. When the subjects were classified into salt-resistant and salt-sensitive groups, genotypic distribution was nearly identical between both groups (frequency of T allele: 0.45 versus 0.46). CONCLUSION Our findings demonstrate that the AGT 235T allele is significantly associated with a positive family history of hypertension, but is not an important determinant of the blood pressure response to dietary salt intake in young normotensive subjects. It is therefore unlikely that the AGT 235T genotype can serve as an early genetic marker of salt sensitivity.
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Affiliation(s)
- U Schorr
- Department of Internal Medicine, Universitätsklinikum Benjamin Franklin, Free University of Berlin, Germany
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Staessen JA, Kuznetsova T, Wang JG, Emelianov D, Vlietinck R, Fagard R. M235T angiotensinogen gene polymorphism and cardiovascular renal risk. J Hypertens 1999; 17:9-17. [PMID: 10100088 DOI: 10.1097/00004872-199917010-00003] [Citation(s) in RCA: 143] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
OBJECTIVE In this meta-analysis, we attempted to derive pooled estimates for the putative associations between various cardiovascular-renal disorders and the M235T polymorphism of the angiotensinogen gene. METHODS Case-control studies were combined, using the Mantel and Haenszel approach. Joint P values for continuous variables were calculated by Stouffer's method. Continuous measurements reported in different units were expressed on a percentage scale using the intrastudy mean of the MM genotype as denominator. RESULTS The computerized database used for this analysis included 69 reports with an overall sample size of 27,906 subjects. Overall, possession of the T allele was associated with an increased risk of hypertension. In comparison with the MM reference group (number of studies, n = 32), the excess risk was 31% (P = 0.001) in TT homozygotes and 11% (P = 0.03) in TM heterozygotes. The sensitivity analysis showed that this association was present only in whites (T allelic frequency, f = 42.2%), but not in blacks (f = 77.0%) or Asians (f = 78.0%). Atherosclerotic complications (n = 12), renal microvascular disorders (n = 13), cardiomyopathy (n = 2) or diabetic retinopathy (n = 3) were not correlated with the M235T polymorphism. Publication bias was observed for hypertension, but not for coronary heart disease, including myocardial infarction, and for microvascular nephropathy. Furthermore, in comparison with the MM control group, the circulating angiotensinogen levels (n = 8) were raised by 11 and 7% (P = 0.01) in TT and TM subjects, respectively. In contrast, plasma levels of the angiotensin I converting enzyme (n = 4) and body mass index (n = 15) were not associated with the T allele. CONCLUSION The T allele encoding angiotensinogen is not associated with atherosclerotic or microvascular complications, but in Caucasians behaves as a marker for hypertension. This association, which may have been inflated by publication bias, does not necessarily imply causality.
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Affiliation(s)
- J A Staessen
- Hypertension and Cardiovascular Rehabilitation Unit, University of Leuven, Belgium
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15
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Celentano A, Mancini FP, Crivaro M, Palmieri V, De Stefano V, Ferrara LA, Di Minno G, de Simone G. Influence of cardiovascular risk factors on relation between angiotensin converting enzyme-gene polymorphism and blood pressure in arterial hypertension. J Hypertens 1998; 16:985-91. [PMID: 9794739 DOI: 10.1097/00004872-199816070-00012] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
BACKGROUND The angiotensin-converting enzyme gene insertion (I)/deletion (D) polymorphism might be involved in the development of several cardiovascular diseases, but its role in humans remains controversial. OBJECTIVE To investigate the relation between the angiotensin converting enzyme gene polymorphism and extent of blood pressure elevation in arterial hypertension, taking into account the influence of cardiovascular risk factors. METHODS We studied 171 patients (aged 49 +/- 9 years, 61 women) with abnormal clinic and 24 h ambulatory blood pressures, after a 3-week wash-out. RESULTS We found no significant difference in clinic and ambulatory blood pressures among homozygotic D (DD), heterozygotic D (ID) and homozygotic I (II) angiotensin converting enzyme genotypes and between homozygotic D (DD) and pooled heterozygotic D (ID) plus homozygotic I (II) (non-DD) angiotensin converting enzyme genotypes. At least one additional cardiovascular risk factor (smoking, hypercholesterolaemia or diabetes) was present for 103 patients (33 DD and 70 non-DD). Non-DD subjects (n = 43) without additional cardiovascular risk factors exhibited lower values of 24 h, daytime systolic and pulse blood pressures than did members of all other groups (all P < 0.04). In the presence of risk factors, DD and non-DD subjects exhibited similar systolic and pulse ambulatory blood pressures, in that we found higher values in non-DD genotype subjects with risk factors than we did for non-DD subjects without additional risk factors. In multivariate analysis, the combination of non-DD genotype and absence of cardiovascular risk factors was associated with the lowest values of systolic and pulse blood pressures. CONCLUSIONS Angiotensin converting enzyme insertion allele appears clustered with lower ambulatory systolic and pulse blood pressures in hypertensive patients when the potential interference of additional cardiovascular risk factors is eliminated. A high prevalence of cardiovascular risk factors in population studies might blunt a possible biological association of blood pressure with DD genotype by contributing to raising of blood pressures also in subjects with non-DD genotypes.
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Affiliation(s)
- A Celentano
- Department of Clinical and Experimental Medicine, Federico II University Hospital, School of Medicine, Naples, Italy.
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Vasků A, Soucek M, Znojil V, Rihácek I, Tschöplová S, Strelcová L, Cídl K, Blazková M, Hájek D, Hollá L, Vácha J. Angiotensin I-converting enzyme and angiotensinogen gene interaction and prediction of essential hypertension. Kidney Int 1998; 53:1479-82. [PMID: 9607178 DOI: 10.1046/j.1523-1755.1998.00924.x] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
To prove whether the interaction between insertion/deletion (I/D) angiotensin I converting enzyme (ACE) and M235T angiotensinogen (AGT) gene polymorphic alleles could contribute to causing essential hypertension, we examined subjects from the Czech Republic (365 Caucasians total; 202 normotensives and 163 hypertensives). Subjects were genotyped for insertion/deletion polymorphism of ACE (I/D ACE, intron 16) and for M235T polymorphism of angiotensinogen gene (AGT, exon 2) by means of the polymerase chain reaction (PCR) method. The case-control approach was used. Fisher's exact test followed by Holmes's test to overcome the problem of multiple comparisons were used for the statistical analysis of data. No association of single gene allelic variants with essential hypertension was found in our population. Having compared only double homozygote combinations, the association of the DDMM genotype with essential hypertension was proven (P = 0.0081). To the contrary, IITT (P = 0.0086) was found more frequently in normotensive subjects. We conclude that the interaction of the I/D ACE and M235T AGT polymorphic alleles can contribute to essential hypertension, despite the absence of single gene associations with the condition.
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Affiliation(s)
- A Vasků
- Institute of Pathological Physiology, Medical Faculty of Masaryk University, Brno, Czech Republic.
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