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Powell NR, Shugg T, Leighty J, Martin M, Kreutz RP, Eadon MT, Lai D, Lu T, Skaar TC. Analysis of the combined effect of rs699 and rs5051 on angiotensinogen expression and hypertension. Chronic Dis Transl Med 2024; 10:102-117. [PMID: 38872760 PMCID: PMC11166681 DOI: 10.1002/cdt3.103] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2023] [Revised: 10/23/2023] [Accepted: 11/06/2023] [Indexed: 06/15/2024] Open
Abstract
Background Hypertension (HTN) involves genetic variability in the renin-angiotensin system and influences antihypertensive response. We previously reported that angiotensinogen (AGT) messenger RNA (mRNA) is endogenously bound by miR-122-5p and rs699 A > G decreases reporter mRNA in the microRNA functional-assay PASSPORT-seq. The AGT promoter variant rs5051 C > T is in linkage disequilibrium (LD) with rs699 A > G and increases AGT transcription. The independent effect of these variants is understudied due to their LD therefore we aimed to test the hypothesis that increased AGT by rs5051 C > T counterbalances AGT decreased by rs699 A > G, and when these variants occur independently, it translates to HTN-related phenotypes. Methods We used in silico, in vitro, in vivo, and retrospective models to test this hypothesis. Results In silico, rs699 A > G is predicted to increase miR-122-5p binding affinity by 3%. Mir-eCLIP results show rs699 is 40-45 nucleotides from the strongest microRNA-binding site in the AGT mRNA. Unexpectedly, rs699 A > G increases AGT mRNA in an AGT-plasmid-cDNA HepG2 expression model. Genotype-Tissue Expression (GTEx) and UK Biobank analyses demonstrate liver AGT expression and HTN phenotypes are not different when rs699 A > G occurs independently from rs5051 C > T. However, GTEx and the in vitro experiments suggest rs699 A > G confers cell-type-specific effects on AGT mRNA abundance, and suggest paracrine renal renin-angiotensin-system perturbations could mediate the rs699 A > G associations with HTN. Conclusions We found that rs5051 C > T and rs699 A > G significantly associate with systolic blood pressure in Black participants in the UK Biobank, demonstrating a fourfold larger effect than in White participants. Further studies are warranted to determine if altered antihypertensive response in Black individuals might be due to rs5051 C > T or rs699 A > G. Studies like this will help clinicians move beyond the use of race as a surrogate for genotype.
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Affiliation(s)
- Nicholas R. Powell
- Division of Clinical Pharmacology, Department of MedicineSchool of Medicine, Indiana UniversityIndianapolisIndianaUSA
| | - Tyler Shugg
- Division of Clinical Pharmacology, Department of MedicineSchool of Medicine, Indiana UniversityIndianapolisIndianaUSA
| | - Jacob Leighty
- Division of Clinical Pharmacology, Department of MedicineSchool of Medicine, Indiana UniversityIndianapolisIndianaUSA
| | - Matthew Martin
- Department of Pharmacology and ToxicologySchool of Medicine, Indiana UniversityIndianapolisIndianaUSA
| | - Rolf P. Kreutz
- Department of CardiologySchool of Medicine, Krannert Institute of Cardiology, Indiana UniversityIndianapolisIndianaUSA
| | - Michael T. Eadon
- Division of Nephrology, Department of MedicineSchool of Medicine, Indiana UniversityIndianapolisIndianaUSA
- Department of Medical and Molecular GeneticsSchool of Medicine, Indiana UniversityIndianapolisIndianaUSA
| | - Dongbing Lai
- Department of Medical and Molecular GeneticsSchool of Medicine, Indiana UniversityIndianapolisIndianaUSA
| | - Tao Lu
- Department of Pharmacology and ToxicologySchool of Medicine, Indiana UniversityIndianapolisIndianaUSA
| | - Todd C. Skaar
- Division of Clinical Pharmacology, Department of MedicineSchool of Medicine, Indiana UniversityIndianapolisIndianaUSA
- Department of Medical and Molecular GeneticsSchool of Medicine, Indiana UniversityIndianapolisIndianaUSA
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Powell NR, Shugg T, Leighty J, Martin M, Kreutz RP, Eadon MT, Lai D, Lu T, Skaar TC. Analysis of the Combined Effect of rs699 and rs5051 on Angiotensinogen Expression and Hypertension. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.04.07.536073. [PMID: 37066278 PMCID: PMC10104131 DOI: 10.1101/2023.04.07.536073] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/18/2023]
Abstract
Hypertension (HTN) involves genetic variability in the renin-angiotensin system and characterizing this variability will help advance precision antihypertensive treatments. We previously reported that angiotensinogen (AGT) mRNA is endogenously bound by mir-122-5p and that rs699 A>G significantly decreases reporter mRNA in the functional mirSNP assay PASSPORT-seq. The AGT promoter variant rs5051 C>T is in linkage disequilibrium (LD) with rs699 A>G and increases AGT transcription. We hypothesized that the increased AGT by rs5051 C>T counterbalances AGT decrease by rs699 A>G, and when these variants occur independently, would translate to HTN-related phenotypes. The independent effect of each of these variants is understudied due to their LD, therefore, we used in silico, in vitro, in vivo, and retrospective clinical and biobank analyses to assess HTN and AGT expression phenotypes where rs699 A>G occurs independently from rs5051 C>T. In silico, rs699 A>G is predicted to increase mir-122-5p binding strength by 3%. Mir-eCLIP assay results show that rs699 is 40-45 nucleotides from the strongest microRNA binding site in the AGT mRNA. Unexpectedly, rs699 A>G increases AGT mRNA in a plasmid cDNA HepG2 expression model. GTEx and UK Biobank analyses demonstrate that liver AGT expression and HTN phenotypes were not different when rs699 A>G occurs independently from rs5051 C>T, allowing us to reject the original hypothesis. However, both GTEx and our in vitro experiments suggest rs699 A>G confers cell-type specific effects on AGT mRNA abundance. We found that rs5051 C>T and rs699 A>G significantly associate with systolic blood pressure in Black participants in the UK Biobank, demonstrating a 4-fold larger effect than in White participants. Further studies are warranted to determine if the altered antihypertensive response in Black individuals might be due to rs5051 C>T or rs699 A>G. Studies like this will help clinicians move beyond the use of race as a surrogate for genotype.
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Affiliation(s)
- Nicholas R. Powell
- Indiana University School of Medicine, Department of Medicine, Division of Clinical Pharmacology, Indianapolis IN
| | - Tyler Shugg
- Indiana University School of Medicine, Department of Medicine, Division of Clinical Pharmacology, Indianapolis IN
| | - Jacob Leighty
- Indiana University School of Medicine, Department of Medicine, Division of Clinical Pharmacology, Indianapolis IN
| | - Matthew Martin
- Indiana University School of Medicine, Department of Pharmacology and Toxicology, Indianapolis IN
| | - Rolf P. Kreutz
- Indiana University School of Medicine, Department of Cardiology, Krannert Institute of Cardiology, Indianapolis IN
| | - Michael T. Eadon
- Indiana University School of Medicine, Department of Medicine, Division of Nephrology, Indianapolis IN
- Indiana University School of Medicine, Department of Medical and Molecular Genetics, Indianapolis IN
| | - Dongbing Lai
- Indiana University School of Medicine, Department of Medical and Molecular Genetics, Indianapolis IN
| | - Tao Lu
- Indiana University School of Medicine, Department of Pharmacology and Toxicology, Indianapolis IN
| | - Todd C. Skaar
- Indiana University School of Medicine, Department of Medicine, Division of Clinical Pharmacology, Indianapolis IN
- Indiana University School of Medicine, Department of Medical and Molecular Genetics, Indianapolis IN
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Umeukeje EM, Young BA. Genetics and ESKD Disparities in African Americans. Am J Kidney Dis 2019; 74:811-821. [PMID: 31606237 PMCID: PMC7373097 DOI: 10.1053/j.ajkd.2019.06.006] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2018] [Accepted: 06/09/2019] [Indexed: 12/22/2022]
Abstract
African Americans have a 2- to 4-fold greater incidence of end-stage kidney disease (ESKD) than whites, which has long raised the possibility of a genetic cause for this disparity. Recent advances in genetic studies have shown a causal association of polymorphisms at the apolipoprotein L1 gene (APOL1) with the markedly increased risk for the nondiabetic component of the overall disparity in ESKD in African Americans. Although APOL1-associated kidney disease is thought to account for a substantial proportion of ESKD in African Americans, not all the increased risk for ESKD is accounted for, and a complete cataloging of disparities in genetic causes of ESKD eludes our current understanding of genetic-associated kidney disease. Genetic testing aids the screening, diagnosis, prognosis, and treatment of diseases with a genetic basis. Widespread use of genetic testing in clinical practice is limited by the small number of actionable genetic variants, limited health literacy of providers and patients, and underlying complex ethical, legal, and social issues. This perspective reviews racial and ethnic differences associated with genetic diseases and the development of ESKD in African Americans and discusses potential uncertainties associated with our current understanding of penetrance of genetically linked kidney disease and population-attributable risk percent.
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Affiliation(s)
- Ebele M Umeukeje
- Division of Nephrology, Vanderbilt University Medical Center, Nashville, TN; Vanderbilt Center for Kidney Disease, Nashville, TN
| | - Bessie A Young
- Nephrology, Hospital and Specialty Medicine and Center for Innovation for Veteran-Centered and Value Driven Care, Veterans Affairs Puget Sound Health Care System, Seattle, WA; Kidney Research Institute and Division of Nephrology, University of Washington, Seattle, WA.
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Yang YL, Mo YP, He YS, Yang F, Xu Y, Li CC, Wang J, Reng HM, Long L. Correlation between renin-angiotensin system gene polymorphisms and essential hypertension in the Chinese Yi ethnic group. J Renin Angiotensin Aldosterone Syst 2015; 16:975-81. [PMID: 26283679 DOI: 10.1177/1470320315598697] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2015] [Accepted: 06/16/2015] [Indexed: 12/31/2022] Open
Abstract
INTRODUCTION The renin-angiotensin system (RAS) has been considered to play an important role in the regulation of blood pressure. This study aimed to investigate the correlation between RAS gene polymorphisms and essential hypertension (EH) in the Chinese Yi ethnic group. MATERIALS AND METHODS A total of 244 EH subjects and 185 normotensive individuals from the Chinese Yi ethnic group were genotyped for AGT M235T (rs699), AT1R A1166C (rs5186), ACE I/D (rs4340) and ACE G2350A (rs4343) polymorphisms by the polymerase chain reaction (PCR)-restriction fragment length polymorphism (RFLP) method. RESULTS Significant differences in the allele and genotype frequency of ACE G2350A were observed between the EH cases and controls (p=0.001, 0.002). After being grouped by gender, significant differences in the allele and genotype frequency of ACE G2350A and AT1R A1166C were observed between females of the EH cases and controls (ACE G2350A: p=0.000, 0.002; AT1R A1166C: p=0.008, 0.011). After excluding the influence of multifactorial interactions, the ACE G2350A polymorphism is significantly associated with the pathogenesis of EH in the Chinese Yi ethnic group (odds ratio (OR)=1.656, 95% confidence interval (CI) 1.807-2.524, p=0.019). CONCLUSIONS The RAS-related ACE G2350A polymorphism is associated with the pathogenesis of EH in the Chinese Yi ethnic group.
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Affiliation(s)
- Yu-Ling Yang
- Department of Cell Biology and Medical Genetics, Kunming Medical University, China
| | - Yan-Ping Mo
- Department of Geriatrics, The First Affiliated Hospital of Kunming Medical University, China
| | - Yong-Shu He
- Department of Cell Biology and Medical Genetics, Kunming Medical University, China
| | - Fang Yang
- Department of Cell Biology and Medical Genetics, Kunming Medical University, China
| | - Yan Xu
- Department of Pathogenic Biology and Immunology, Kunming Medical University, China
| | - Cheng-Cheng Li
- School of Basic Medical Science, Kunming Medical University, China
| | - Jiao Wang
- School of Basic Medical Science, Kunming Medical University, China
| | - Hao-Ming Reng
- School of Basic Medical Science, Kunming Medical University, China
| | - Li Long
- Department of Cell Biology and Medical Genetics, Kunming Medical University, China
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Nakamura A. Genotypes of the renin-angiotensin system and glucocorticoid complications. Pediatr Int 2015; 57:72-8. [PMID: 24980618 DOI: 10.1111/ped.12434] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/19/2014] [Revised: 05/21/2014] [Accepted: 05/26/2014] [Indexed: 01/14/2023]
Abstract
BACKGROUND Angiotensinogen (AGT) and angiotensin-converting enzyme (ACE) are recognized as important regulators of body mass index (BMI) and systemic blood pressure (BP). An association between these single nucleotide polymorphisms (SNP) of AGT and ACE genes and obesity or hypertension has been established. This study examined relationships between the molecular variants of the AGT and ACE genes and bodyweight or BP in children treated with glucocorticoids for nephrotic syndrome. METHODS Twenty Japanese children (male, n = 14; female, n = 6; age, 2-13 years) were genotyped for AGT polymorphisms (M235T and A-6G) and the ACE polymorphisms (insertion/deletion: I/D and rs4341). All of the children studied were treated with daily prednisolone 2 mg/kg for 4 weeks and thereafter alternate-day prednisolone for 8 weeks. BMI, BMI z-scores, blood lipids, renal function and BP in each group were evaluated during the study period. RESULTS BMI and BMI z-scores during the glucocorticoid therapy were significantly higher in the TT genotype of the AGT M235T polymorphisms and the AA genotype of the AGT A-6G polymorphisms compared to other genotypes (P < 0.05). In contrast, the molecular variant of ACE I/D and rs4341 genotypes did not change bodyweight during the glucocorticoid exposure. It was evident, however, that the BP and blood lipids and renal function were not significantly influenced by the AGT and ACE polymorphisms. CONCLUSIONS The TT genotype of the AGT M235T and the AA genotype of the A-6G polymorphisms may predispose children to bodyweight gain when initially treated with glucocorticoids for nephrotic syndrome.
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Affiliation(s)
- Akio Nakamura
- Department of Paediatrics, Teikyo University School of Medicine, Tokyo, Japan; Department of Paediatrics, Social Insurance Omiya General Hospital, Saitama, Japan
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Hara M, Sakata Y, Nakatani D, Suna S, Usami M, Matsumoto S, Sugitani T, Ozaki K, Nishino M, Sato H, Kitamura T, Nanto S, Hamasaki T, Tanaka T, Hori M, Komuro I. Renin-angiotensin-aldosterone system polymorphisms and 5-year mortality in survivors of acute myocardial infarction: a report from the Osaka Acute Coronary Insufficiency Study. Int Heart J 2014; 55:190-6. [PMID: 24806378 DOI: 10.1536/ihj.13-288] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
This study sought to evaluate whether genetic variants in the renin-angiotensin-aldosterone system (RAAS) have an impact on long-term mortality after acute myocardial infarction (AMI) in the percutaneous coronary intervention (PCI) era. We investigated the impacts of individual and combinations of 4 major RAAS genetic variants, angiotensinogen (AGT) T1311C, angiotensin-converting enzyme (ACE) insertion/deletion (I/D), angiotensin 2 type 1 receptor A1166C, and aldosterone synthase T4660C on 5-year mortality in 3149 post-AMI patients using multivariate Cox regression analysis. The predictive accuracy of all possible RAAS genetic combinations was evaluated using Cox regression analysis, and the best combination that affected prognosis was determined based on the minimal Akaike Information Criterion. There were 220 deaths during a median follow-up of 4.9 years. Independent analyses of any single RAAS variant did not show significant impacts on 5-year mortality. However, analyses in combination revealed that absence of both AGT CC genotype and ACE D allele was associated with lower 5-year mortality (log-rank P = 0.005). Patients with at least either of the AGT CC or ACE D allele had increased mortality with adjusted hazard ratios of 2.07 (95% confidence interval 1.18-3.65, P = 0.012), compared with those with neither the AGT CC nor ACE D allele. Among the 4 RAAS genetic variants examined, a combination of AGT and ACE polymorphisms was associated with 5-year mortality after AMI.
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Affiliation(s)
- Masahiko Hara
- Department of Cardiovascular Medicine, Osaka University Graduate School of Medicine
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Padma G, Swapna N, Mamata M, Charita B, Padma T. Risk conferred by tagged SNPs of AGT gene in causing susceptibility to essential hypertension. Clin Exp Hypertens 2014; 36:579-85. [PMID: 24490766 DOI: 10.3109/10641963.2014.881845] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
UNLABELLED Abstract Introduction: AGT gene harbors several variants of which 21 are found to be in high linkage disequilibrium as per Hapmap database. Studies delineating the importance of these tagged SNPs are very limited and lacking from Indian population. In the present study, we evaluated the contribution of four tagged SNPs namely, g.6635G > A, g.6506G > A, g.12840G > A, and g.13828T > C at AGT locus along with the analyses of haplotype and epistatic interactions in causing susceptibility to essential hypertension (EHT). METHODS About 215 hypertensives and 230 normotensives were genotyped for selected tagged SNPs using PCR-RFLP method. RESULTS Significant association was obtained for g.6635G > A and g.6506G > A polymorphisms wherein GG homozygotes for both the markers were at risk for developing the condition. g.13828T > C polymorphism specially, female heterozygotes (TC) were found to be at increased risk for EHT. Haplotype GGGC was found to have a significant protective effect (p = 0.0059). Markers g.6506G > A and g.12840G > A resulted in the creation of new enhancer sites thereby affecting splicing process. CONCLUSION The present report is the first one in the literature showing general- and gender-specific association of g.6506G > A and g.13828T > C polymorphisms, respectively, with EHT. However, further studies for replication of present observations are warranted from other populations and other parts of India.
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Affiliation(s)
- G Padma
- Department of Genetics, Osmania University , Tarnaka, Hyderabad, Andhra Pradesh , India and
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Padma G, Charita B, Swapna N, Mamata M, Padma T. Novel variants detected in AGT gene among patients with essential hypertension. J Renin Angiotensin Aldosterone Syst 2014; 16:642-6. [PMID: 24452034 DOI: 10.1177/1470320313513483] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2013] [Accepted: 10/09/2013] [Indexed: 11/17/2022] Open
Abstract
INTRODUCTION AGT is the first gene to be linked to essential hypertension (EHT). It harbors several variants of which only few polymorphisms are found to exhibit positive and negative associations with hypertension. In the present study, the AGT gene was screened to detect already reported and novel variations contributing to the development of hypertension. METHOD In total, 215 hypertensives and 230 normotensives were screened for variations in all the five exons and a part of promoter of AGT gene using single strand conformation polymorphism analysis followed by sequencing of samples showing mobility shifts on polyacrylamide gels. RESULTS Five novel variants, namely c.-61G>A in promoter, c.-4+17C>T in intron1, c.24T>C and c.28A>T in Exon2, and c.*90 T>C in 3' untranslated region were detected in the AGT gene. c.-61G>A lies in the promoter region that plays a critical role in its expression. Variation c.-4+17C>T created a new enhancer site. c.24T>C (TCT-TCC) is a silent mutation while c.28A>T (p. M10L) has a possible damaging effect on the AGT protein. c.*90T>C, detected in the 3' untranslated region is thought to play an important role in the translation and stability of the mRNA. CONCLUSION Studies on the functional role of these novel variants are warranted to understand the mechanism underlying the development of EHT.
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Affiliation(s)
- G Padma
- Department of Genetics, Osmania University, Tarnaka, Hyderabad, India
| | - Bh Charita
- Sandor Proteomics Pvt Ltd, Hyderabad, India
| | - N Swapna
- Department of Genetics, Osmania University, Tarnaka, Hyderabad, India
| | - M Mamata
- Department of Genetics, Osmania University, Tarnaka, Hyderabad, India
| | - T Padma
- Department of Genetics, Osmania University, Tarnaka, Hyderabad, India
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Meroufel DN, Médiène-Benchekor S, Dumont J, Benhamamouch S, Amouyel P, Brousseau T. A study on the polymorphisms of the renin-angiotensin system pathway genes for their effect on blood pressure levels in males from Algeria. J Renin Angiotensin Aldosterone Syst 2013; 15:1-6. [PMID: 23592589 DOI: 10.1177/1470320313485898] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
INTRODUCTION Several studies have assessed the relationship between blood pressure (BP) and polymorphisms within the genes encoding angiotensinogen (AGT), angiotensin II type 1 receptor (AT1R) and angiotensin-converting enzyme (ACE). However, considering the relatively large discrepancy in frequency and impact of these variants between ethnic groups and populations, still unavailable data from Algerian population are needed. OBJECTIVE Our purpose is to evaluate the association between the AGT M235T, AT1R +1166A/C and ACE I/D polymorphisms and variations in systolic (SBP), diastolic (DBP) and pulse pressure (PP) values. METHODS The associations with BP were assessed in a representative sample of 115 male subjects free of coronary heart disease (CHD). The AGT M235T, AT1R +1166A/C and ACE I/D polymorphisms were determined by PCR-ASO and PCR-RFLP analysis, respectively. RESULTS We showed no associations between the AGT M235T, AT1R +1166A/C nor the ACE I/D polymorphisms with variations in BP values. However, concerning the ACE I/D polymorphism, subjects carrying the ACE I allele tended to have higher SBP (+4.1 mmHg) and PP values (+3.2 mmHg) than DD subjects (adjusted p = 0.087 and p = 0.102, respectively). CONCLUSION The ACE I/D polymorphism needs further investigation in a larger Algerian study, especially concerning its putative impact on SBP and PP.
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Affiliation(s)
- Djabaria Naïma Meroufel
- 1Laboratoire de Génétique Moléculaire et Cellulaire, Université des Sciences et de la Technologie d'Oran Mohammed Boudiaf, Algeria
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Furusawa T, Naka I, Yamauchi T, Natsuhara K, Eddie R, Kimura R, Nakazawa M, Ishida T, Inaoka T, Matsumura Y, Ataka Y, Ohtsuka R, Ohashi J. Hypertension-susceptibility gene prevalence in the Pacific Islands and associations with hypertension in Melanesia. J Hum Genet 2013; 58:142-9. [PMID: 23324949 DOI: 10.1038/jhg.2012.147] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Human essential hypertension is partly caused by genetic factors. Angiotensinogen (AGT), G-protein β3-subunit (GNB3) and cytochrome P450 3A5 (CYP3A5) are candidate hypertension susceptibility genes and risk alleles at these loci have been thought to arise owing to human adaptation to climatic changes following the migration out-of-Africa. This study aimed to reveal the frequencies of hypertension-susceptibility genotypes in Pacific Island populations and associations of these single-nucleotide polymorphisms (SNPs) to hypertension. Genotyping was conducted for 804 individuals from Melanesian, Micronesian and Polynesian populations at SNPs in the genes encoding AGT (rs699, rs5049 and rs5051), GNB3 (rs5443) and CYP3A5*1/*3 (rs776746). Associations between these SNPs and hypertension were tested for 383 Melanesian Solomon Islanders. We found that the A/A genotype at rs5049 was a risk factor for hypertension (P=0.025) in the Melanesian Solomon Islanders; three SNPs for AGT were in linkage disequilibrium. The ancestral alleles of rs699, rs5051 and rs776746, and the derived allele of rs5443 were as frequent in the populations surveyed here as in other equatorial populations. Although other polymorphisms associated with hypertension and additional populations remain to be studied, these findings suggest that the Pacific Islanders' susceptibility to hypertension arose because of human migration and adaptation.
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Affiliation(s)
- Takuro Furusawa
- Graduate School of Asian and African Area Studies, Kyoto University, Kyoto, Japan.
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Charita B, Padma G, Sushma P, Deepak P, Padma T. Estimation of risk and interaction of single nucleotide polymorphisms at angiotensinogen locus causing susceptibility to essential hypertension: a case control study. J Renin Angiotensin Aldosterone Syst 2012; 13:461-71. [DOI: 10.1177/1470320312444650] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Affiliation(s)
- Bh Charita
- Department of Genetics, Osmania University, India
| | - G Padma
- Department of Genetics, Osmania University, India
| | - P Sushma
- Department of Genetics, Osmania University, India
| | - P Deepak
- Gandhi Medical College and Hospital, India
| | - T Padma
- Department of Genetics, Osmania University, India
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Balam-Ortiz E, Esquivel-Villarreal A, Huerta-Hernandez D, Fernandez-Lopez JC, Alfaro-Ruiz L, Muñoz-Monroy O, Gutierrez R, Figueroa-Genis E, Carrillo K, Elizalde A, Hidalgo A, Rodriguez M, Urushihara M, Kobori H, Jimenez-Sanchez G. Hypercontrols in genotype-phenotype analysis reveal ancestral haplotypes associated with essential hypertension. Hypertension 2012; 59:847-53. [PMID: 22371359 DOI: 10.1161/hypertensionaha.111.176453] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
The angiotensinogen gene locus has been associated with essential hypertension in most populations analyzed to date. Increased plasma angiotensinogen levels have been proposed as an underlying cause of essential hypertension in whites; however, differences in the genetic regulation of plasma angiotensinogen levels have also been reported for other populations. The aim of this study was to analyze the relationship between angiotensinogen gene polymorphisms and haplotypes with plasma angiotensinogen levels and the risk of essential hypertension in the Mexican population. We genotyped 9 angiotensinogen gene polymorphisms in 706 individuals. Four polymorphisms, A-6, C4072, C6309, and G12775, were associated with increased risk, and the strongest association was found for the C6309 allele (χ(2)=23.9; P=0.0000009), which resulted in an odds ratio of 3.0 (95% CI: 1.8-4.9; P=0.000006) in the recessive model. Two polymorphisms, A-20C (P=0.003) and C3389T (P=0.0001), were associated with increased plasma angiotensinogen levels but did not show association with essential hypertension. The haplotypes H1 (χ(2)=8.1; P=0.004) and H5 (χ(2)=5.1; P=0.02) were associated with essential hypertension. Using phylogenetic analysis, we found that haplotypes 1 and 5 are the human ancestral haplotypes. Our results suggest that the positive association between angiotensinogen gene polymorphisms and haplotypes with essential hypertension is not simply explained by an increase in plasma angiotensinogen concentration. Complex interactions between risk alleles suggest that these haplotypes act as "superalleles."
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Affiliation(s)
- Eros Balam-Ortiz
- National Institute of Genomic Medicine (INMEGEN), Mexico City, Mexico.
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Balam-Ortiz E, Esquivel-Villarreal A, Alfaro-Ruiz L, Carrillo K, Elizalde A, Gil T, Urushihara M, Kobori H, Jimenez-Sanchez G. Variants and haplotypes in angiotensinogen gene are associated with plasmatic angiotensinogen level in Mexican population. Am J Med Sci 2011; 342:205-11. [PMID: 21629041 DOI: 10.1097/maj.0b013e3182121020] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
INTRODUCTION The plasmatic angiotensinogen (AGT) level has been associated with essential hypertension. Linkage analysis has found a relationship between the AGT gene locus and hypertension in the Mexican-American population, but studies have failed to identify genetic variants associated with hypertension or plasma AGT levels. This study analyzes the relationship between polymorphisms in the AGT gene and plasmatic AGT levels in Mexican population. METHODS Nine polymorphisms in AGT gene were genotyped, and plasma AGT level was determined by enzyme-linked immunosorbent assay. RESULTS Differences in AGT plasma levels were associated with 2 polymorphisms: T-20G, TT = 25.3 ± 8.3 versus TG + GG = 21.6 ± 8.8 μg/mL; P = 0.008 and C3389T (T174M), CC = 25.8 ± 9.9 versus TC + TT = 20.5 ± 5.4 μg/mL; P = 0.0002. Haplotype 2 was associated with low plasma AGT (-5.1 μg/mL [95% confidence interval: -8.6 to -1.6], P = 0.004) and Haplotype 8 was associated with high plasma AGT (6.5 μg/mL [95% confidence interval: 2.5 to 10.6], P = 0.001). This association remained after adjustment for covariates. A Likelihood Ratio Test for haplotype-phenotype association adjusted for covariates resulted in χ = 38.9, P = 0.0005. The total effect of the haplotypes on plasma AGT level variance was 19.5%. No association was identified between haplotypes and quantitative traits of blood pressure. CONCLUSIONS Two polymorphisms (T-20G and C3389T) and 2 haplotypes (H2 and H8) showed an association with plasma AGT levels in Mexican population.
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Affiliation(s)
- Eros Balam-Ortiz
- Division of Cardiovascular Genomics, National Institute of Genomic Medicine (INMEGEN), Mexico City, Mexico.
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Association of angiotensinogen gene M235T and angiotensin-converting enzyme gene I/D polymorphisms with essential hypertension in Han Chinese population: a meta-analysis. J Hypertens 2010; 28:419-28. [PMID: 20087216 DOI: 10.1097/hjh.0b013e32833456b9] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
BACKGROUND The polymorphisms of angiotensinogen (AGT) and angiotensin-converting enzyme (ACE) genes have been linked to increased risk of essential hypertension in multiple populations, but the results were inconsistent. OBJECTIVES AND METHODS To evaluate the associations of these polymorphisms with essential hypertension, we carried out a meta-analysis of the association studies within Han Chinese population. In this study, we reviewed two most commonly investigated polymorphisms, AGT M235T and ACE I/D, and provided summary estimates regarding their associations with essential hypertension. PubMed and China Biological Medicine Database were searched, and a total of 71 studies (31 studies for AGT M235T and 40 studies for ACE I/D) comprising 10 547 essential hypertension patients and 9217 controls from 23 provinces and special districts in China were finally included in this study. RESULTS Statistically significant associations with essential hypertension were identified for TT genotype of AGT M235T polymorphism (odds ratio 1.54, 95% confidence interval 1.16-2.03, P = 0.002) and DD genotype of ACE I/D polymorphism (odds ratio 1.61, 95% confidence interval 1.32-1.98, P < 0.0001). Under dominant, recessive, and additive genetic models, positive associations were also found. The heterogeneity existed among the studies (P < 0.05), whereas the publication bias did not exist in both AGT analysis (P = 0.052) and ACE analysis (P = 0.103). CONCLUSION The present meta-analysis suggests that AGT M235T and ACE I/D modulate the risk of essential hypertension in Han Chinese population.
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Gene variants of the renin–angiotensin system and hypertension: from a trough of disillusionment to a welcome phase of enlightenment? Clin Sci (Lond) 2010; 118:487-506. [DOI: 10.1042/cs20090498] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
There is substantial evidence to suggest that BP (blood pressure) is an inherited trait. The introduction of gene technologies in the late 1980s generated a sharp phase of over-inflated prospects for polygenic traits such as hypertension. Not unexpectedly, the identification of the responsible loci in human populations has nevertheless proved to be a considerable challenge. Common variants of the RAS (renin–angiotensin system) genes, including of ACE (angiotensin-converting enzyme) and AGT (angiotensinogen) were some of the first shown to be associated with BP. Presently, ACE and AGT are the only gene variants with functional relevance, where linkage studies showing relationships with hypertension have been reproduced in some studies and where large population-based and prospective studies have demonstrated these genes to be predictors of hypertension or BP. Nevertheless, a lack of reproducibility in other linkage and association studies has generated scepticism that only a concerted effort to attempt to explain will rectify. Without these explanations, it is unlikely that this knowledge will translate into the clinical arena. In the present review, we show that many of the previous concerns in the field have been addressed, but we also argue that a considerable amount of careful thought is still required to achieve enlightenment with respect to the role of RAS genes in hypertension. We discuss whether the previously identified problems of poor study design have been completely addressed with regards to the impact of ACE and AGT genes on BP. In the context of RAS genes, we also question whether the significance of ‘incomplete penetrance’ through associated environmental, phenotypic or physiological effects has been duly accounted for; whether appropriate consideration has been given to epistatic interactions between genes; and whether future RAS gene studies should consider variation across the gene by evaluating ‘haplotypes’.
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Pereira TV, Nunes ACF, Rudnicki M, Yamada Y, Pereira AC, Krieger JE. Meta-analysis of the association of 4 angiotensinogen polymorphisms with essential hypertension: a role beyond M235T? Hypertension 2008; 51:778-83. [PMID: 18227406 DOI: 10.1161/hypertensionaha.107.100370] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
Angiotensinogen (AGT) gene polymorphisms have been linked to increased risk of hypertension, but the data remain controversial. In this study we review the most commonly investigated polymorphisms at the AGT locus (other than M235T) and provide summary estimates regarding their association with essential hypertension, while addressing heterogeneity, as well as publication biases. Data on 26 818 subjects from 46 studies for the 4 most-studied AGT variants (T174M in exon 2 and 3 promoter variants: A-6G, A-20C, and G-217A) were meta-analyzed. Statistically significant associations with hypertension were identified for the T174M (odds ratio [OR]: 1.19; 95% CI: 1.07 to 1.33; P=0.002) and G-217A (OR: 1.37; 95% CI: 1.17 to 1.59; P=0.00006) polymorphisms. A dual but consistent effect was observed for the -20C allele, which was associated with a decreased risk of hypertension in populations of mixed and European ancestries (OR: 0.64; 95% CI: 0.44 to 0.92; P=0.02 and OR: 0.77; 95% CI: 0.65 to 0.91; P=0.003, respectively), but with a 24% increase in the odds of hypertension in Asian subjects (OR: 1.24; 95% CI: 1.04 to 1.48; P=0.02). No association of the A-6G variant with hypertension was detected. Current studies support the notion that single variants at the AGT might modulate the risk of hypertension but indicate caution in interpreting these results because of the putative presence of publication bias and gene-environment interactions.
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Affiliation(s)
- Tiago Veiga Pereira
- Heart Institute (InCor), Faculty of Pharmaceutical Sciences, University of Sao Paulo Medical School, São Paulo, Brazil
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Carey RM. Pathophysiology of Primary Hypertension. Microcirculation 2008. [DOI: 10.1016/b978-0-12-374530-9.00020-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Baker M, Rahman T, Hall D, Avery PJ, Mayosi BM, Connell JMC, Farrall M, Watkins H, Keavney B. The C-532T polymorphism of the angiotensinogen gene is associated with pulse pressure: a possible explanation for heterogeneity in genetic association studies of AGT and hypertension. Int J Epidemiol 2007; 36:1356-62. [PMID: 17998241 DOI: 10.1093/ije/dym213] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
BACKGROUND Many previous studies have investigated whether there is an association between genotypes at the angiotensinogen (AGT) gene and hypertensive status, but few have incorporated quantitative data. Although meta-analyses support a possible effect of AGT variants on blood pressure (BP), substantial unexplained between-study heterogeneity has been observed. We hypothesized that a primary effect of AGT variants on arterial stiffness (and thus pulse pressure) might explain such heterogeneity, and tested for such an effect in a family study. METHODS We studied 1425 individuals from 248 families ascertained through a proband with essential hypertension. BP was measured using 24 h ambulatory monitoring, and polymorphisms of the AGT gene that had been previously associated with hypertension and/or plasma angiotensinogen levels were typed. Pulse pressure was used as a measurement of arterial stiffness. RESULTS We observed a highly significant association between genotypes at the AGT C-532T polymorphism and pulse pressure (p = 0.00006). Each T allele was associated with a 5% lower pulse pressure (that is, an additive effect). This resulted from opposing genotypic effects to (slightly) lower systolic BP and (slightly) elevate DBP. CONCLUSIONS These results suggest that genetic variation at the angiotensinogen locus may primarily affect arterial stiffness, and therefore pulse pressure. The heterogeneity between previous genetic studies of AGT and hypertension status could in part be explained by this finding, since case selection criteria based on systolic BP, diastolic BP, or both would result in different levels of selection for the -532T allele.
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Affiliation(s)
- Michelle Baker
- The Institute of Human Genetics, Newcastle University, UK
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Lao O, Dupanloup I, Barbujani G, Bertranpetit J, Calafell F. The Mediterranean paradox for susceptibility factors in coronary heart disease extends to genetics. Ann Hum Genet 2007; 72:48-56. [PMID: 17683517 DOI: 10.1111/j.1469-1809.2007.00387.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
The incidence of coronary heart disease (CHD) shows a North to South gradient in Europe. We tested whether that gradient could be accounted for by the distribution of putative susceptibility genotypes. We correlated the published frequencies of susceptibility genotypes for the genes most often associated with CHD (ACE, AGT, APOE, F2, F5, MTHFR, PON1, and SERPINE1) with the incidence of the disease, controlling for the effects of smoking, systolic pressure, total cholesterol, and body-mass index. In three polymorphisms a negative correlation between the incidence of CHD and the frequency of a suceptibility genotype was observed. For ACE this correlation was significantly negative even when discounting classical susceptibility factors. This suggests that some alleles described as susceptibility factors cannot account for disease incidence at the population level. A genetic component must be added to the "Mediterranean paradox": genetic variants deemed to be risk factors for CHD show a geographical pattern uncorrelated with the disease incidence. This pattern can be understood from the history of populations which has shaped the genetic diversity of the European populations in North-South clines, similar to what is observed for CHD incidence, which will tend to create spurious correlations with polymorphisms related, or not related, to the disease.
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Affiliation(s)
- Oscar Lao
- Unitat de Biologia Evolutiva, Departament de Ciències Experimentals i de la Salut, Universitat Pompeu Fabra, Barcelona, Catalonia, Spain
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Arnett DK, Baird AE, Barkley RA, Basson CT, Boerwinkle E, Ganesh SK, Herrington DM, Hong Y, Jaquish C, McDermott DA, O'Donnell CJ. Relevance of Genetics and Genomics for Prevention and Treatment of Cardiovascular Disease. Circulation 2007; 115:2878-901. [PMID: 17515457 DOI: 10.1161/circulationaha.107.183679] [Citation(s) in RCA: 156] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Atherosclerotic cardiovascular disease (CVD) is a major health problem in the United States and around the world. Evidence accumulated over decades convincingly demonstrates that family history in a parent or a sibling is associated with atherosclerotic CVD, manifested as coronary heart disease, stroke, and/or peripheral arterial disease. Although there are several mendelian disorders that contribute to CVD, most common forms of CVD are believed to be multifactorial and to result from many genes, each with a relatively small effect working alone or in combination with modifier genes and/or environmental factors. The identification and the characterization of these genes and their modifiers would enhance prediction of CVD risk and improve prevention, treatment, and quality of care. This scientific statement describes the approaches researchers are using to advance understanding of the genetic basis of CVD and details the current state of knowledge regarding the genetics of myocardial infarction, atherosclerotic CVD, hypercholesterolemia, and hypertension. Current areas of interest and investigation--including gene-environment interaction, pharmacogenetics, and genetic counseling--are also discussed. The statement concludes with a list of specific recommendations intended to help incorporate usable knowledge into current clinical and public health practice, foster and guide future research, and prepare both researchers and practitioners for the changes likely to occur as molecular genetics moves from the laboratory to clinic.
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Rosskopf D, Schürks M, Rimmbach C, Schäfers R. Genetics of arterial hypertension and hypotension. Naunyn Schmiedebergs Arch Pharmacol 2007; 374:429-69. [PMID: 17262198 DOI: 10.1007/s00210-007-0133-2] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2006] [Accepted: 12/22/2006] [Indexed: 01/13/2023]
Abstract
Human hypertension affects affects more than 20% of the adult population in industrialized countries, and it is implicated in millions of deaths worldwide each year from stroke, heart failure and ischemic heart disease. Available evidence suggests a major genetic impact on blood pressure regulation. Studies in monogenic hypertension revealed that renal salt and volume regulation systems are predominantly involved in the genesis of these disorders. Mutations here affect the synthesis of mineralocorticoids, the function of the mineralocorticoid receptor, epithelial sodium channels and their regulation by a new class of kinases, termed WNK kinases. It has been learned from monogenic hypotension that almost all ion transporters involved in the renal uptake of Na(+) have a major impact on blood pressure regulation. For essential hypertension as a complex disease, many candidate genes have been analysed. These include components of the renin-angiotensin-aldosterone system, adducin, beta-adrenoceptors, G protein subunits, regulators of G protein signalling (RGS) proteins, Rho kinases and G protein receptor kinases. At present, the individual impact of common polymorphisms in these genes on the observed blood pressure variation, on risk for stroke and as predictors of antihypertensive responses remains small and clinically irrelevant. Nevertheless, these studies have greatly augmented our knowledge on the regulation of renal functions, cellular signal transduction and the integration of both. Together, this provides the basis for the identification of novel drug targets and, hopefully, innovative antihypertensive drugs.
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Affiliation(s)
- Dieter Rosskopf
- Department Pharmacology, Research Center for Pharmacology and Experimental Therapeutics, Ernst-Moritz-Arndt-University Greifswald, Friedrich Loeffler Str. 23d, 17487 Greifswald, Germany.
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Nakamura Y, Tabara Y, Miki T, Tamaki S, Kita Y, Okamura T, Ueshima H. Both angiotensinogen M235T and alpha-adducin G460W polymorphisms are associated with hypertension in the Japanese population. J Hum Hypertens 2007; 21:253-5. [PMID: 17215849 DOI: 10.1038/sj.jhh.1002135] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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NIU W, QI Y, CEN W, CUI C, ZHUOMA C, CAI D, ZHOU W, QIU C. Genetic Polymorphisms of Angiotensinogen and Essential Hypertension in a Tibetan Population. Hypertens Res 2007; 30:1129-37. [DOI: 10.1291/hypres.30.1129] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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Wu X, Cooper RS. Genetics of Hypertension. Hypertension 2007. [DOI: 10.1016/b978-1-4160-3053-9.50008-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Takakura Y, Yoshida T, Yoshioka K, Umekawa T, Kogure A, Toda H, Kagawa K, Fukui S, Yoshikawa T. Angiotensinogen gene polymorphism (Met235Thr) influences visceral obesity and insulin resistance in obese Japanese women. Metabolism 2006; 55:819-24. [PMID: 16713443 DOI: 10.1016/j.metabol.2006.02.008] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/05/2004] [Accepted: 02/01/2006] [Indexed: 11/24/2022]
Abstract
To investigate the relationship between angiotensinogen (AGT) Met235Thr polymorphism (M235T) and human obesity, because AGT is regarded as one of the cytokines produced from adipocytes and serum AGT concentrations are reported to be positively correlated with body mass index. One hundred and twenty obese Japanese women (age, 58.8+/-9.4 years; body mass index, 32.2+/-4.9 kg/m(2)) were enrolled. Angiotensinogen genotypes were determined with a fluorescent allele-specific DNA primer assay system. Subjects were divided into M/M, M/T, and T/T groups. Control subjects comprised 146 healthy age-matched women. Clinical characteristics and the effects of diet and exercise therapy for 6 months were compared among the 3 genotypes. The genotype frequencies of AGT M235T polymorphism were in accordance with the Hardy-Weinberg equation (obese: M/M, 6.7%; M/T, 27.5%; T/T, 65.8%; control: M/M, 6.8%; M/T, 21.2%; T/T, 71.9%). The frequency of the T allele did not differ between obese and control subjects (0.80 vs 0.83). As the number of obese women with M/M genotype was only 8, comparisons of the characteristics and outcomes of weight reduction therapy were performed only between subjects with M/T genotype and T/T genotype. In the T/T group, % body fat and waist circumference at baseline were significantly greater than in the M/T group (36.3%+/-4.8% vs 33.8%+/-4.7%, P=.0105; 107.9+/-10.9 vs 102.6+/-7.9 cm, P=.0428, respectively). Before the weight reduction therapy, significantly higher insulin and higher homeostasis model assessment (HOMA-R) were demonstrated in the T/T group than in the M/T group (9.1+/-5.5 microU/mL vs 5.9+/-4.4 microU/mL, P=.0056; 2.3+/-1.4 vs 1.6+/-1.3, P=.0252, respectively). Both systolic and diastolic blood pressure at baseline in the T/T group tended to be higher than those in the M/T group, but the differences were not significant. No genotype-dependent difference in energy expenditure or outcome of weight reduction therapy was observed with respect to AGT M235T polymorphism. After the diet and exercise therapy, the blood pressure in the T/T group tended to be higher than that in the M/T group, but the difference was not significant. We demonstrated that the T/T genotype of the AGT M235T gene polymorphism was positively related to visceral obesity and hyperinsulinemia in obese Japanese women. Blood pressure did not show genotype-specific differences before or after the treatment. Further studies of the association between obesity and this gene polymorphism should contribute to understanding and treating obesity-related diseases.
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Affiliation(s)
- Yasuto Takakura
- Department of Internal Medicine, Fukuchiyama City Hospital, Fukuchiyama 620-8505, Japan.
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Minelli C, Thompson JR, Abrams KR, Lambert PC. Bayesian implementation of a genetic model-free approach to the meta-analysis of genetic association studies. Stat Med 2006; 24:3845-61. [PMID: 16320276 DOI: 10.1002/sim.2393] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
A genetic model-free method for the meta-analysis of genetic association studies is described that estimates the mode of inheritance from the data rather than assuming that it is known. For a bi-allelic polymorphism, with G as risk allele and g as wild-type, the genetic model depends on the ratio of the two log odds ratios, lambda = log OR(Gg)/log OR(GG), where OR(GG) compares GG with gg and OR(Gg) compares Gg with gg. Modelling log OR(GG) as a random effect creates a hierarchical model that can be implemented within a Bayesian framework. In Bayesian modelling, vague prior distributions have to be specified for all unknown parameters when no external information is available. When the data are sparse even supposedly vague prior distributions may have an influence on the posterior estimates. We investigate the impact of different vague prior distributions for the between-study standard deviation of log OR(GG) and for lambda, by considering three published meta-analyses and associated simulations. Our results show that depending on the characteristics of the meta-analysis the results may indeed be sensitive to the choice of vague prior distribution for either parameter. Genetic association studies usually use a case-control design that should be analysed by the corresponding retrospective likelihood. However, under some circumstances the prospective likelihood has been shown to produce identical results and it is usually preferred for its simplicity. In our meta-analyses the two likelihoods give very similar results.
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Affiliation(s)
- Cosetta Minelli
- Centre for Biostatistics and Genetic Epidemiology, Department of Health Sciences, University of Leicester, Leicester, UK.
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Abstract
Hypertension is a multifactorial disorder that probably results from the inheritance of a number of susceptibility genes and involves multiple environmental determinants. Existing evidence suggests that the genetic contribution to blood pressure variation is about 30-50%. Although a number of candidate genes have been studied in different ethnic populations, results from genetic analysis are still inconsistent and specific causes of hypertension remain unclear. Furthermore, the abundance of data in the literature makes it difficult to piece together the puzzle of hypertension and to define candidate genes involved in the dynamic of blood pressure regulation. In this review, we attempt to highlight the genetic basis of hypertension pathogenesis, focusing on the most important existing genetic variations of candidate genes and their potential role in the development of this disease. Our objective is to review current knowledge and discuss limitations to clinical applications of genotypic information in the diagnosis, evaluation and treatment of hypertension. Finally, some principles of pharmacogenomics are presented here along with future perspectives of hypertension.
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Affiliation(s)
- Jean-Brice Marteau
- INSERM U525, Equipe 4, Faculté de Pharmacie, Université Henri Poincare, Nancy, France
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Minelli C, Thompson JR, Abrams KR, Thakkinstian A, Attia J. The choice of a genetic model in the meta-analysis of molecular association studies. Int J Epidemiol 2005; 34:1319-28. [PMID: 16115824 DOI: 10.1093/ije/dyi169] [Citation(s) in RCA: 147] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
BACKGROUND To evaluate gene-disease associations, genetic epidemiologists collect information on the disease risk in subjects with different genotypes (for a bi-allelic polymorphism: gg, Gg, GG). Meta-analyses of such studies usually reduce the problem to a single comparison, either by performing two separate pairwise comparisons or by assuming a specific underlying genetic model (recessive, co-dominant, dominant). A biological justification for the choice of the genetic model is seldom available. METHODS We present a genetic model-free approach, which does not assume that the underlying genetic model is known in advance but still makes use of the information available on all genotypes. The approach uses OR(GG), the odds ratio between the homozygous genotypes, to capture the magnitude of the genetic effect, and lambda, the heterozygote log odds ratio as a proportion of the homozygote log odds ratio, to capture the genetic mode of inheritance. The analysis assumes that the same unknown genetic model, i.e. the same lambda, applies in all studies, and this is investigated graphically. The approach is illustrated using five examples of published meta-analyses. RESULTS Analyses based on specific genetic models can produce misleading estimates of the odds ratios when an inappropriate model is assumed. The genetic model-free approach gives appropriately wider confidence intervals than genetic model-based analyses because it allows for uncertainty about the genetic model. In terms of assessment of model fit, it performs at least as well as a bivariate pairwise analysis in our examples. CONCLUSIONS The genetic model-free approach offers a unified approach that efficiently estimates the genetic effect and the underlying genetic model. A bivariate pairwise analysis should be used if the assumption of a common genetic model across studies is in doubt.
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Affiliation(s)
- Cosetta Minelli
- Department of Health Sciences, Centre for Biostatistics and Genetic Epidemiology, University of Leicester, Leicester, UK.
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Wu SJ, Chiang FT, Chen WJ, Liu PH, Hsu KL, Hwang JJ, Lai LP, Lin JL, Tseng CD, Tseng YZ. Three single-nucleotide polymorphisms of the angiotensinogen gene and susceptibility to hypertension: single locus genotype vs. haplotype analysis. Physiol Genomics 2004; 17:79-86. [PMID: 14970360 DOI: 10.1152/physiolgenomics.00133.2003] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Although some single polymorphism analyses of the angiotensinogen (AGT) gene have been found to be associated with hypertension, the results are still inconsistent. The objectives of this study are to evaluate the association of the genotype and haplotype distributions of three single-nucleotide polymorphisms (SNPs) (G−217A, A−6G, and M235T) in the AGT gene with hypertension. In a sample of 461 hypertensive and 327 normotensive patients in Taiwan, we found that −217AA and −6GG homozygotes conferred independently an increased risk to hypertension ( P = 0.008 and P = 0.037, respectively), as illustrated by their significant associations with hypertension in both single SNP and pair-wise SNPs analyses. Meanwhile, a very weak linkage disequilibrium was found between the G−217A and the A−6G polymorphisms in terms of r2 (<0.05). On the basis of likelihood ratio test, only the set of haplotypes that constituted the A−6G and the M235T polymorphisms was associated with hypertension (χ2 = 20.91, P = 0.0008), which was mainly due to the increased frequency of the recombinant haplotypes (−6A ≡ 235M and −6G ≡ 235T), and a pathophysiological role in the predisposition to hypertension was hence indicated. In functional assays, the promoter activities of the haplotypes −217A ≡ −6A and −217G ≡ −6G were significantly higher than the most common haplotype −217G ≡ −6A. These results highlight the necessity of a thorough analysis of all reported variants of a candidate gene in the elucidation of genetic susceptibility to a complex disease like hypertension, even when the variants are in the same haplotype block.
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Affiliation(s)
- Shyh-Jong Wu
- Graduate Institute of Physiology, National Taiwan University College of Medicine, Taipei 100, Taiwan
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Williams SM, Haines JL, Moore JH. The use of animal models in the study of complex disease: all else is never equal or why do so many human studies fail to replicate animal findings? Bioessays 2004; 26:170-9. [PMID: 14745835 DOI: 10.1002/bies.10401] [Citation(s) in RCA: 58] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
The study of the genetics of complex human disease has met with limited success. Many findings with candidate genes fail to replicate despite seemingly overwhelming physiological data implicating the genes. In contrast, animal model studies of the same genes and disease models usually have more consistent results. We propose that one important reason for this is the ability to control genetic background in animal studies. The fact that controlling genetic background can produce more consistent results suggests that the failure to replicate human findings in the same diseases is due to variation in interacting genes. Hence, the contrasting nature of the findings from the different study designs indicates the importance of non-additive genetic effects on human disease. We discuss these issues and some methodological approaches that can detect multilocus effects, using hypertension as a model disease. This article contains supplementary material, which may be viewed at the BioEssays website at http://www.interscience.wiley.com/jpages/0265-9247/suppmat/index.html.
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Affiliation(s)
- Scott M Williams
- Division of Cardiovascular Medicine, Vanderbilt University Medical Center, Nashville, TN 37232, USA.
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Wu SJ, Chiang FT, Jiang JR, Hsu KL, Chern TH, Tseng YZ. The G???217A variant of the angiotensinogen gene affects basal transcription and is associated with hypertension in a Taiwanese population. J Hypertens 2003; 21:2061-7. [PMID: 14597849 DOI: 10.1097/00004872-200311000-00015] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
OBJECTIVE Polymorphisms of the angiotensinogen (AGT) gene, especially in the promoter region, are in linkage concordance and are associated with hypertension. In this study, we examined the role of AGT promoter polymorphisms, including G-217A, A-6G and M235T variants, and their promoter function in essential hypertension in Taiwanese populations. DESIGN An association study was conducted to assess the genotype distribution between hypertensive patients and normotensive subjects. We also used a transient transfection assay to examine basal transcriptional activity of G-217A and A-6G variants in a mammalian cell system. METHODS Hypertensive subjects (390) and normotensive controls (388) of Taiwanese ethnicity were genotyped for the AGT G-217A, A-6G and M235T variants. Promoter activity was studied by cloning the promoter region (-614 to +41 bp) of AGT into the pSEAP2-Basic reporter vector and performing a transient transfection assay in HuH7 and HepG2 cells. RESULTS The G-217A variant of the AGT gene was significantly associated with hypertension (P = 0.0047), but the A-6G and M235T polymorphisms were not (P = 0.17 and P = 0.33, respectively). Furthermore, the recessive model of homozygous genotype (-217AA) conferred a high risk for hypertension (odds ratio 3.64) in this population. The -217A variant expressed higher transcriptional activity than -217G in vitro. CONCLUSIONS Our study showed a significant association between the -217A variant of the AGT gene and hypertension. This variant plays a functional role in basal transcription of AGT, and may confer a risk for hypertension in Taiwanese populations.
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Affiliation(s)
- Shyh-Jong Wu
- Department of Physiology, National Taiwan University College of Medicine, National Taiwan University Hospital, Taipei, Taiwan, ROC
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Narita I, Goto S, Saito N, Song J, Omori K, Kondo D, Sakatsume M, Gejyo F. Angiotensinogen gene variation and renoprotective efficacy of renin-angiotensin system blockade in IgA nephropathy. Kidney Int 2003; 64:1050-8. [PMID: 12911556 DOI: 10.1046/j.1523-1755.2003.00187.x] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
BACKGROUND Blockade of the renin-angiotensin system (RAS) is well documented to be renoprotective; however, not all patients with glomerulonephritis respond well to this therapy. The interindividual variation in response to the RAS blockade may be in part genetically determined, whereas the results have been controversial. METHODS We investigated whether the therapeutic efficacy of angiotensin-converting enzyme (ACE) inhibitors and/or angiotensin receptor blocker on renal prognosis is modified by the angiotensinogen gene (AGT) polymorphism in immunoglobulin A nephropathy (IgAN). In total, 259 patients with histologically proven IgAN were analyzed for clinical manifestations, renal survival, and their associations with AGT A(-20)C and M235T. RESULTS The renal prognosis of 110 patients, who received ACE inhibitors/angiotensin receptor blocker during their clinical course, was significantly better than those without ACE inhibitors/angiotensin receptor blockers despite higher blood pressures and heavier proteinuria. The Cox proportional hazards regression model showed an increased hazard ratio (HR) for urinary protein (more than 1.0 g/day) of 3.346 (P = 0.0001), hypertension of 1.949 (P = 0.01), deteriorated renal function of 3.040 (P < 0.0001), no ACE inhibitor/angiotensin receptor blocker administration of 2.725 (P = 0.0004), and the T235 and C(-20) haplotype of 1.608 (P = 0.0322). Only in patients carrying at least one M235 and A(-20) haplotype did the administration of ACE inhibitors/angiotensin receptor blockers have no significant effect on the prognosis of renal function (Kaplan-Meier, log rank test, chi2 = 0.700; P = 0.4028), whereas it was significant in patients who had other haplotypes of AGT (chi2 = 11.805; P = 0.0006). CONCLUSION This study provides evidence that the M235T and A(-20)C genotype of AGT can influence the therapeutic efficacy of a RAS blockade on the renal survival in IgAN.
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Affiliation(s)
- Ichiei Narita
- Division of Clinical Nephrology and Rheumatology, Niigata University Graduate School of Medical and Dental Sciences, Niigata, Japan.
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Wu Z, Nakura J, Abe M, Jin JJ, Yamamoto M, Chen Y, Tabara Y, Yamamoto Y, Igase M, Bo X, Kohara K, Miki T. Genome-wide linkage disequilibrium mapping of hypertension in Japan. Hypertens Res 2003; 26:533-40. [PMID: 12924620 DOI: 10.1291/hypres.26.533] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Hypertension is a common, complex phenotype resulting from the interaction between genetic and environmental factors. To select candidate regions potentially responsible for hypertension, we are conducting a genome-wide linkage disequilibrium (LD) mapping of hypertension using dinucleotide repeat markers in 146 hypertensive and 136 normotensive subjects. Although the LD mapping is still underway, 19 alleles of 15 markers have already shown a nominally significant association (p<0.05), with odds ratios ranging from 0.08 to 5.12, suggesting the presence of many hypertension-related loci with weak effects in the human genome. These markers should be further assessed, adjusting for confounding factors and considering gene-gene and gene-environmental interactions in additional samples. In this report, we discuss our ongoing LD mapping project and describe the 15 markers thus far discovered. Among the 15 markers, D10S537 had a highly significant association with hypertension (p=5.3x10(-5); OR=3.80; 95% CI=1.98-7.27; where OR indicates the odds ratio and 95% CI indicates the 95% confidence interval). Further analysis in a large Japanese population showed that D10S537 was significantly associated with hypertension (p=0.044; OR=1.27; 95% CI=1.01-1.59). D10S537 was more significantly associated with hypertension in subjects with normotriglyceridemia in our population (p=0.007; OR=1.47; 95% CI=1.11-1.95).
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Affiliation(s)
- Zhihong Wu
- Department of Geriatric Medicine, School of Medicine, Ehime University, Onsen-gun, Ehime, Japan
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Sethi AA, Nordestgaard BG, Tybjaerg-Hansen A. Angiotensinogen gene polymorphism, plasma angiotensinogen, and risk of hypertension and ischemic heart disease: a meta-analysis. Arterioscler Thromb Vasc Biol 2003; 23:1269-75. [PMID: 12805070 DOI: 10.1161/01.atv.0000079007.40884.5c] [Citation(s) in RCA: 155] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
OBJECTIVE The aim of this study was to investigate whether the M235T polymorphism in the angiotensinogen gene was associated with angiotensinogen levels, systolic and diastolic blood pressure, hypertension, and risk of ischemic cardiovascular disease in different ethnic populations. METHODS AND RESULTS One hundred twenty-seven studies published between January 1992 and March 2002 examining the association of angiotensinogen gene polymorphisms with the above-mentioned end points were selected. Pooled effect sizes and Mantel-Haenszel odds ratios were calculated using Review Manager. In white subjects, genotype was associated with a stepwise increase in plasma angiotensinogen levels of 5% (95% CI, 2% to 8%; P=0.0004) in MT heterozygotes and 11% (7% to 15%; P<0.00001) in TT homozygotes compared with MM individuals. Correspondingly, genotype was associated with a stepwise increase in aggregated odds ratio for hypertension of 1.08 (95% CI, 1.01 to 1.15) in MT individuals and 1.19 (1.10 to 1.30) in TT individuals in white subjects and of 1.29 (95% CI, 0.96 to 1.74) and 1.60 (1.19 to 2.15) in Asian subjects. M235T genotype did not predict systolic or diastolic blood pressure or risk of ischemic heart disease or myocardial infarction in either ethnic group. CONCLUSIONS Angiotensinogen M235T genotype was associated with a stepwise increase in angiotensinogen levels in white subjects and a corresponding increase in risk of hypertension in both white and Asian subjects.
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Affiliation(s)
- Amar Akhtar Sethi
- Department of Clinical Biochemistry, Herlev University Hospital, Copenhagen, Denmark.
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Kohara K, Tabara Y, Yamamoto Y, Igase M, Nakura J, Miki T. Genotype-specific association between circulating soluble cellular adhesion molecules and carotid intima-media thickness in community residents: J-SHIPP study. Shimanami Health Promoting Program. Hypertens Res 2002; 25:31-9. [PMID: 11924723 DOI: 10.1291/hypres.25.31] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Plasma levels of soluble forms of cellular adhesion molecules (CAMs) and their relationships with carotid intima-media thickness (IMT) were investigated in community residents. Plasma levels of soluble intercellular adhesion molecule-1 (sICAM-1) and soluble vascular cell adhesion molecule-1 (sVCAM-1) were measured by ELISA in 200 community residents in Japan. Carotid IMT showed a weak but significant positive correlation with the plasma levels of both sICAM-1 (r=0.175, p=0.013) and sVCAM-1 (r=0.19, p=0.0075). Gene polymorphisms of angiotensin converting enzyme (ACE) insertion/deletion (I/D), angiotensinogen (AGT) M235T, angiotensin II type 1 receptor (AT1R) A1166C and apolipoprotein E (apoE) were determined for each subject. The plasma level of sVCAM-1 tended to be lower in subjects with the ACE DD genotype than in those with the ACE ID and II genotypes (373+/-94, 421+/-133, 443+/-135 ng/ml, respectively, p=0.056). However, there were no genotype-specific differences in the plasma levels of soluble forms of CAMs for the other genes examined. In a separate analysis, the plasma level of sICAM-1 was significantly associated with carotid IMT in ACE D carriers (ID + DD) (r=0.28, p=0.002), AGT M carriers (MT + MM) (r=0.32, p=0.0045), and subjects with apoE4 (r=0.35, p=0.036). In contrast, the plasma level of sVCAM-1 showed significant positive correlations with carotid IMT in subjects with the ACE II genotype (r=0.33, p=0.0027) or AGT TT genotype (r= 0.22, p=0.015), and subjects with apoE E2/E3 or E3/E3 (r=0.16, p=0.043). Stepwise regression analysis showed that plasma sVCAM-1 was independently associated with carotid IMT in subjects with the ACE II genotype or apoE4 genotype. Similarly, the plasma level of sICAM-1 was independently associated with carotid IMT in AGT M carriers. These findings suggest that genetic background could be involved in the association between plasma CAMs and atherosclerosis.
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Affiliation(s)
- Katsuhiko Kohara
- Department of Geriatric Medicine, Ehime University School of Medicine, Japan.
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Nakajima T, Jorde LB, Ishigami T, Umemura S, Emi M, Lalouel JM, Inoue I. Nucleotide diversity and haplotype structure of the human angiotensinogen gene in two populations. Am J Hum Genet 2002; 70:108-23. [PMID: 11731937 PMCID: PMC384882 DOI: 10.1086/338454] [Citation(s) in RCA: 99] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2001] [Accepted: 10/26/2001] [Indexed: 11/03/2022] Open
Abstract
Variation in the angiotensinogen gene, AGT, has been associated with variation in plasma angiotensinogen levels. In addition, the T235M polymorphism in the AGT product is associated with an increased risk of essential hypertension in multiple populations, making AGT a good example of a quantitative-trait locus underlying susceptibility to a common disease. To better understand genetic variation in AGT, we sequenced a 14.4-kb genomic region spanning the entire AGT and identified 44 single-nucleotide polymorphisms (SNPs). Forty-two SNPs were observed both in 88 white and in 77 Japanese unselected subjects. Six major haplotypes accounted for most of the variation in this region, indicating less allelic complexity than in many other genomic regions. Although the two populations were found to share all of the major AGT haplotypes, there were substantial differences in haplotype frequencies. Pairwise linkage disequilibrium (LD), measured by the D', r(2), and d(2) statistics, demonstrated a general pattern of decline with increasing distance, but, as expected in a small genomic region, individual LD values were highly variable. LD between T235M and each of the other 39 SNPs was assessed in order to model the usefulness of LD to detect a disease-associated mutation. Among the Japanese subjects, 13 (33%) of the SNPs had r(2) values >0.1, whereas this statistic was substantially higher for the white subjects (occurring in 35/39 [90%]). LD between a hypertension-associated promoter mutation, A-6G, and 39 SNPs was also measured. Similar results were obtained, with 33% of the SNPs showing r(2)>0.1 in the Japanese subjects and 92% of the SNPs showing r(2)>0.1 in the white subjects. This difference, which occurs despite an overall similarity in LD patterns in the two populations, reflects a much higher frequency of the M235-associated haplotype in the white sample. These results have important implications for the usefulness of LD approaches in the mapping of genes underlying susceptibility to complex diseases.
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Affiliation(s)
- Toshiaki Nakajima
- Division of Genetic Diagnosis, The Institute of Medical Science, The University of Tokyo, Tokyo; Department of Human Genetics, University of Utah Health Sciences Center, Salt Lake City; Internal Medicine, Yokohama City University, Yokohama; and Department of Molecular Biology, Institute of Gerontology, Nippon Medical School, Kawasaki, Japan
| | - Lynn B. Jorde
- Division of Genetic Diagnosis, The Institute of Medical Science, The University of Tokyo, Tokyo; Department of Human Genetics, University of Utah Health Sciences Center, Salt Lake City; Internal Medicine, Yokohama City University, Yokohama; and Department of Molecular Biology, Institute of Gerontology, Nippon Medical School, Kawasaki, Japan
| | - Tomoaki Ishigami
- Division of Genetic Diagnosis, The Institute of Medical Science, The University of Tokyo, Tokyo; Department of Human Genetics, University of Utah Health Sciences Center, Salt Lake City; Internal Medicine, Yokohama City University, Yokohama; and Department of Molecular Biology, Institute of Gerontology, Nippon Medical School, Kawasaki, Japan
| | - Satoshi Umemura
- Division of Genetic Diagnosis, The Institute of Medical Science, The University of Tokyo, Tokyo; Department of Human Genetics, University of Utah Health Sciences Center, Salt Lake City; Internal Medicine, Yokohama City University, Yokohama; and Department of Molecular Biology, Institute of Gerontology, Nippon Medical School, Kawasaki, Japan
| | - Mitsuru Emi
- Division of Genetic Diagnosis, The Institute of Medical Science, The University of Tokyo, Tokyo; Department of Human Genetics, University of Utah Health Sciences Center, Salt Lake City; Internal Medicine, Yokohama City University, Yokohama; and Department of Molecular Biology, Institute of Gerontology, Nippon Medical School, Kawasaki, Japan
| | - Jean-Marc Lalouel
- Division of Genetic Diagnosis, The Institute of Medical Science, The University of Tokyo, Tokyo; Department of Human Genetics, University of Utah Health Sciences Center, Salt Lake City; Internal Medicine, Yokohama City University, Yokohama; and Department of Molecular Biology, Institute of Gerontology, Nippon Medical School, Kawasaki, Japan
| | - Ituro Inoue
- Division of Genetic Diagnosis, The Institute of Medical Science, The University of Tokyo, Tokyo; Department of Human Genetics, University of Utah Health Sciences Center, Salt Lake City; Internal Medicine, Yokohama City University, Yokohama; and Department of Molecular Biology, Institute of Gerontology, Nippon Medical School, Kawasaki, Japan
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Affiliation(s)
- R S Danziger
- Division of Cardiology, University of Illinois School of Medicine, Chicago, IL60612-7323, USA.
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Lalouel JM, Rohrwasser A, Terreros D, Morgan T, Ward K. Angiotensinogen in essential hypertension: from genetics to nephrology. J Am Soc Nephrol 2001; 12:606-615. [PMID: 11181811 DOI: 10.1681/asn.v123606] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
Abstract
There is general consensus that genetic variation accounts in part for individual susceptibilities to essential hypertension. In marked contrast to classic mendelian disorders, in which genetic alterations produce a gain or loss of function, genetic determinants of essential hypertension, high blood pressure of unknown cause, are expected to be small, achieving significance through the cumulative effects of environmental exposure over the course of a lifetime. Whether and how genetic factors that contribute to common diseases can be identified remain unclear. Research on a link between angiotensinogen and essential hypertension illustrates a path that began in genetics and is now leading toward nephrology. Various challenges encountered along the way may prove to be characteristic features of genetic investigations of the pathogenesis of common diseases. The implication of a gene by statistical analysis is only the beginning of a protracted process of functional analysis at increasing levels of biologic integration. The ultimate goal is to develop an understanding of the manner in which genetic variation at a locus can affect a physiologic parameter and to extract from this inference new knowledge of significance for the prevention or treatment of disease.
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Affiliation(s)
- Jean-Marc Lalouel
- Department of Human Genetics, University of Utah School of Medicine, Salt Lake City, Utah
- Howard Hughes Medical Institute, University of Utah School of Medicine, Salt Lake City, Utah
| | - Andreas Rohrwasser
- Department of Human Genetics, University of Utah School of Medicine, Salt Lake City, Utah
| | - Daniel Terreros
- Department of Pathology, University of Utah School of Medicine, Salt Lake City, Utah
- Department of Veterans Affairs, Salt Lake City, Utah
| | - Terry Morgan
- Department of Human Genetics, University of Utah School of Medicine, Salt Lake City, Utah
- Department of Obstetrics and Gynecology, University of Utah School of Medicine, Salt Lake City, Utah
| | - Kenneth Ward
- Department of Obstetrics and Gynecology, University of Utah School of Medicine, Salt Lake City, Utah
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Timberlake DS, O'Connor DT, Parmer RJ. Molecular genetics of essential hypertension: recent results and emerging strategies. Curr Opin Nephrol Hypertens 2001; 10:71-9. [PMID: 11195056 DOI: 10.1097/00041552-200101000-00012] [Citation(s) in RCA: 63] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Efforts to identify hypertension-predisposition genetic loci have focused largely on candidate gene strategies, in which specific candidates have been tested for linkage and association with blood pressure or the diagnosis of hypertension. A variety of candidate genes have been investigated, including loci involving the renin-angiotensin-aldosterone system, sodium epithelial channel, catecholaminergic/adrenergic function, renal kallikrein system, alpha-adducin, and others involving lipoprotein metabolism, hormone receptors, and growth factors. These studies, and more recently, several genome-wide scans, have yielded highly promising results suggesting a number of potential candidate genes and genomic regions that may contribute to blood pressure variation. The results also point to the need for more robust phenotypes that are intermediate in the pathogenetic development of high blood pressure. Additional methods and strategies for improving genetic studies of human hypertension include comparative genomics, in which results from animal studies are used to target potential blood pressure loci, the use of newly developed quantitative tests of linkage and association, comprehensive single-nucleotide polymorphism discovery in candidate loci, and the use of single-nucleotide polymorphisms in cladistic/haplotype analyses and genome-wide searches.
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Affiliation(s)
- D S Timberlake
- Department of Medicine, University of California at San Diego, and Veterans Administration Medical Center, 92161, USA
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Wang JG, Staessen JA. Genetic polymorphisms in the renin-angiotensin system: relevance for susceptibility to cardiovascular disease. Eur J Pharmacol 2000; 410:289-302. [PMID: 11134677 DOI: 10.1016/s0014-2999(00)00822-0] [Citation(s) in RCA: 119] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
The renin-angiotensin system plays an important role in the pathogenesis of cardiovascular disease. Cloning of the human genes coding for the angiotensin-converting enzyme, angiotensinogen, and angiotensin II type 1 receptor has led to the discovery of several polymorphisms, which may be implicated in the pathogenesis of cardiovascular disease. The deletion/insertion (D/I) polymorphism of the angiotensin-converting enzyme gene is associated with hypertension in men, left ventricular hypertrophy in untreated hypertensive patients, various atherosclerotic cardiovascular complications, and microvascular disorders. The M235T polymorphism of the angiotensinogen gene may be associated with a higher risk of hypertension. The A1166C polymorphism of the angiotensin II type 1 receptor gene is probably correlated with hypertension and through an epistatic interaction with the D/I polymorphism of the angiotensin-converting enzyme gene possibly also with coronary heart disease. Several other gene polymorphisms, in particular those in the promoter area of the angiotensinogen gene, have been studied in relation to cardiovascular disease. Based on the insights gained from the reports summarized in this review article, population-based genetic studies of nuclear families are currently being conducted in Belgium and in the People's Republic of China with blood pressure and hypertension as the main outcome variables.
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Affiliation(s)
- J G Wang
- Study Coordinating Centre, Hypertension and Cardiovascular Rehabilitation Unit, Department of Molecular and Cardiovascular Research, University of Leuven, Leuven, Belgium
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Iso H, Harada S, Shimamoto T, Sato S, Kitamura A, Sankai T, Tanigawa T, Iida M, Komachi Y. Angiotensinogen T174M and M235T variants, sodium intake and hypertension among non-drinking, lean Japanese men and women. J Hypertens 2000; 18:1197-206. [PMID: 10994750 DOI: 10.1097/00004872-200018090-00005] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
OBJECTIVE To examine the interaction of sodium intake with genetic variations of the angiotensinogen gene and hypertension. DESIGN A community-based case-reference study. SETTING Two rural Japanese communities. PARTICIPANTS Non-overweight and non-drinking Japanese men and women: 229 hypertensives and 229 age-, sex- and community-matched normotensives aged 32 to 83 years. METHODS Polymorphisms of the angiotensinogen gene detected by an allele-specific polymerase chain reaction. A priori hypothesis is individuals with 174M (threonine-to-methionine substitution) or 235T (methionine-to-threonine substitution) allelic variations may have an elevated risk of hypertension when they have a high sodium intake, estimated by 24-h urine collection and a dietary questionnaire. RESULTS The genotypic frequency of the haplotype including both the 174M and 235T alleles was higher among hypertensives than among normotensives (23 versus 14%, P= 0.02). The frequency of the 174M allele was specifically higher among hypertensives than normotensives (12 versus 7%, P=0.01), and the odds ratio of hypertension associated with the 174M (versus 174T) allele was 1.8 [95% confidence interval (CI) 1.1-3.0, P=0.01]. The frequency of the 235T allele did not vary between the two groups (80 versus 82%, P= 0.40). The relationship between the 174M allele and hypertension was more evident among persons who had higher urinary sodium excretion (> = 166 mmol/day) than those with lower excretion (< 166 mmol/day): odds ratio 2.5 (95% CI, 1.2-5.2), P=0.01 versus 1.5 (95% CI, 0.7-3.1), P= 0.31; P for interaction = 0.04, and this trend was primarily observed for early-onset hypertension (< 55 years at onset). A similar but nonsignificant association was observed when stratified using present and past sodium intake scores derived from questionnaires. CONCLUSION Angiotensinogen genotype may affect the development of early-onset hypertension among Japanese, particularly in those who have a high sodium intake.
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Affiliation(s)
- H Iso
- Institute of Community Medicine, University of Tsukuba, Ibaraki-ken, Japan.
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Kato N, Sugiyama T, Morita H, Kurihara H, Furukawa T, Isshiki T, Sato T, Yamori Y, Yazaki Y. Comprehensive analysis of the renin-angiotensin gene polymorphisms with relation to hypertension in the Japanese. J Hypertens 2000; 18:1025-32. [PMID: 10953993 DOI: 10.1097/00004872-200018080-00006] [Citation(s) in RCA: 46] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
BACKGROUND Components of the renin-angiotensin (R-A) system have been repeatedly investigated as candidate genes for essential hypertension. In particular, suggestive or significant association has been detected in some studies for the angiotensinogen M235T, angiotensin I-converting enzyme I/D, angiotensin II type 1 receptor A1166C, and aldosterone synthase C-344T polymorphisms, although the results remain inconclusive. OBJECTIVE AND METHODS To evaluate the importance of these candidate genes for hypertension, we undertook an extensive association study in the Japanese. This case-control study was conducted in a total of 1476 individuals using the four R-A gene polymorphisms. In the assessment of genotyping data, 843 hypertensive subjects were divided into three case subgroups according to severity of hypertension, while 633 normotensive subjects divided into two control subgroups by the age of enrollment. Each subgroup was further divided by sex. Subsequently, the presence of synergy (or gene-gene interaction) was evaluated among four R-A gene polymorphisms. RESULTS No significant association was observed between the individual R-A gene polymorphisms and hypertension status in our case-control study. The results were almost unchanged when severity of hypertension, sex-specificity, and synergy were taken into account CONCLUSIONS Despite a relatively large number of subjects, we did not find significant evidence for disease association in the Japanese population. Given confounding factors in the case-control strategy, the lack of association does not exclude the relevance of the R-A genes to hypertension. Further investigation needs to be performed in large-scale populations, where the use of not only hypertension status, but also 'intermediate' phenotypes would be useful.
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Affiliation(s)
- N Kato
- Department of Internal Medicine, Teikyo University School of Medicine, Tokyo, Japan.
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Abstract
The year 1999 saw considerable activity in the area of hypertension-related molecular genetics. Several new monogenic hypertensive disorders, as well as a monogenic form of hypotension, were elucidated. Molecular genetics has made significant inroads in explaining basic mechanisms of magnesium homeostasis. Linkage strategies have been applied in family studies, sib-pair analyses, and twin studies. More stringent criteria for association studies have been formulated. The 11 beta-hydroxysteroid dehydrogenase gene, the prostacyclin synthase gene, genes coding for variants in G proteins, and adrenergic receptor genes have received particular attention. On the horizon are better phenotyped patient and subject collectives, expanded genotyping with the availability of a 300,000 genome-wide single-nucleotide polymorphism map, multigenic studies in the form of metabolic control analyses, and new bioinformatic strategies including neural networks.
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Affiliation(s)
- F C Luft
- Franz Volhard Clinic, Medical Faculty of the Charité, Humboldt University of Berlin, Germany.
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