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Mabhida SE, Mashatola L, Kaur M, Sharma JR, Apalata T, Muhamed B, Benjeddou M, Johnson R. Hypertension in African Populations: Review and Computational Insights. Genes (Basel) 2021; 12:genes12040532. [PMID: 33917487 PMCID: PMC8067483 DOI: 10.3390/genes12040532] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2021] [Revised: 03/17/2021] [Accepted: 03/18/2021] [Indexed: 01/11/2023] Open
Abstract
Hypertension (HTN) is a persistent public health problem affecting approximately 1.3 billion individuals globally. Treatment-resistant hypertension (TRH) is defined as high blood pressure (BP) in a hypertensive patient that remains above goal despite use of ≥3 antihypertensive agents of different classes including a diuretic. Despite a plethora of treatment options available, only 31.0% of individuals have their HTN controlled. Interindividual genetic variability to drug response might explain this disappointing outcome because of genetic polymorphisms. Additionally, the poor knowledge of pathophysiological mechanisms underlying hypertensive disease and the long-term interaction of antihypertensive drugs with blood pressure control mechanisms further aggravates the problem. Furthermore, in Africa, there is a paucity of pharmacogenomic data on the treatment of resistant hypertension. Therefore, identification of genetic signals having the potential to predict the response of a drug for a given individual in an African population has been the subject of intensive investigation. In this review, we aim to systematically extract and discuss African evidence on the genetic variation, and pharmacogenomics towards the treatment of HTN. Furthermore, in silico methods are utilized to elucidate biological processes that will aid in identifying novel drug targets for the treatment of resistant hypertension in an African population. To provide an expanded view of genetic variants associated with the development of HTN, this study was performed using publicly available databases such as PubMed, Scopus, Web of Science, African Journal Online, PharmGKB searching for relevant papers between 1984 and 2020. A total of 2784 articles were reviewed, and only 42 studies were included following the inclusion criteria. Twenty studies reported associations with HTN and genes such as AGT (rs699), ACE (rs1799752), NOS3 (rs1799983), MTHFR (rs1801133), AGTR1 (rs5186), while twenty-two studies did not show any association within the African population. Thereafter, an in silico predictive approach was utilized to identify several genes including CLCNKB, CYPB11B2, SH2B2, STK9, and TBX5 which may act as potential drug targets because they are involved in pathways known to influence blood pressure. Next, co-expressed genes were identified as they are controlled by the same transcriptional regulatory program and may potentially be more effective as multiple drug targets in the treatment regimens for HTN. Genes belonging to the co-expressed gene cluster, ACE, AGT, AGTR1, AGTR2, and NOS3 as well as CSK and ADRG1 showed enrichment of G-protein-coupled receptor activity, the classical targets of drug discovery, which mediate cellular signaling processes. The latter is of importance, as the targeting of co-regulatory gene clusters will allow for the development of more effective HTN drug targets that could decrease the prevalence of both controlled and TRH.
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Affiliation(s)
- Sihle E. Mabhida
- Biomedical Research and Innovation Platform, South African Medical Research Council, Tygerberg 7505, South Africa; (S.E.M.); (J.R.S.)
- Department of Biotechnology, Faculty of Natural Science, University of the Western Cape, Private Bag X17, Bellville, Cape Town 7535, South Africa;
| | - Lebohang Mashatola
- School of Molecular and Cell Biology, University of the Witwatersrand, Private Bag 3, Johannesburg 2050, South Africa; (L.M.); (M.K.)
| | - Mandeep Kaur
- School of Molecular and Cell Biology, University of the Witwatersrand, Private Bag 3, Johannesburg 2050, South Africa; (L.M.); (M.K.)
| | - Jyoti R. Sharma
- Biomedical Research and Innovation Platform, South African Medical Research Council, Tygerberg 7505, South Africa; (S.E.M.); (J.R.S.)
| | - Teke Apalata
- Division of Medical Microbiology, Department of Laboratory-Medicine and Pathology, Faculty of Health Sciences, Walter Sisulu University and National Health Laboratory Services, Mthatha 5100, South Africa;
| | - Babu Muhamed
- Hatter Institute for Cardiovascular Diseases Research in Africa, Department of Medicine, University of Cape Town, Cape Town 7535, South Africa;
- Children’s National Health System, Division of Cardiology, Washington, DC 20010, USA
| | - Mongi Benjeddou
- Department of Biotechnology, Faculty of Natural Science, University of the Western Cape, Private Bag X17, Bellville, Cape Town 7535, South Africa;
| | - Rabia Johnson
- Biomedical Research and Innovation Platform, South African Medical Research Council, Tygerberg 7505, South Africa; (S.E.M.); (J.R.S.)
- Division of Medical Physiology, Faculty of Medicine and Health Sciences, Stellenbosch University, Tygerberg 7505, South Africa
- Correspondence: ; Tel.: +27-21-938-0866
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Farbood Z, Sabeti Aghabozorgi A, Nejatizadeh A, Farshidi H, Shams L, Bahreyni A, Mansouri Babamansouri E, Shekari M. Endothelial Nitric Oxide Synthase Gene Polymorphisms (- 922A > G, - 786 T > C, Intron 4 b/a VNTR and 894 G > T) and Essential Hypertension: An Association Study with Haplotypes Analysis. Biochem Genet 2020; 58:518-532. [PMID: 32519277 DOI: 10.1007/s10528-020-09953-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2019] [Accepted: 02/12/2020] [Indexed: 11/26/2022]
Abstract
Endothelial Nitric Oxide Synthase (eNOS) is an indispensable regulator of blood pressure through producing Nitric Oxide (NO). There is some evidence to suggest that eNOS gene polymorphisms are associated with Essential Hypertension (EHT). In this study, the potential association between eNOS 4a/4b, A922G, G894T, T786C gene polymorphisms and EHT as individual risk factors and as haplotypes are examined in the southern population of Iran (Bandar-Abbas). In this study, 200 EHT patients and 200 normotensive subjects which were matched for age and sex were included. Genotyping was performed by either utilizing Polymerase Chain Reaction (PCR) or PCR followed by Restriction Fragment length Polymorphism (RFLP) method. Our results demonstrated statistically significant associations between T786C, G894T, and 4a/4a and EHT (p < 0.05); however, A922G had no significant association with EHT (p > 0.05). Haplotype analysis also suggested that - 786C/- 922A/4a, - 786C/- 922A/4b and - 786C/- 922G/4a haplotypes were more frequent in EHT group than control group, hypothesizing a positive association with EHT. The present study has identified that the eNOS genetic variations are associated with EHT in southern population of Iran (Bandar-Abbas). These findings also suggested that a number of haplotypes of eNOS gene may be a driving factor for EHT susceptibility in respected population.
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Affiliation(s)
- Zahra Farbood
- Molecular Medicine Research Center, Hormozgan University of Medical Sciences, Bandar Abbas, Iran
| | | | - Azim Nejatizadeh
- Molecular Medicine Research Center, Hormozgan University of Medical Sciences, Bandar Abbas, Iran
| | - Hossein Farshidi
- Hormozgan Cardiovascular Research Center, Hormozgan University of Medical Sciences, Bandar Abbas, Iran
| | - Leila Shams
- Molecular Medicine Research Center, Hormozgan University of Medical Sciences, Bandar Abbas, Iran
| | - Amirhossein Bahreyni
- Centre for Heart Lung Innovation, St. Paul's Hospital, Vancouver, BC, Canada
- Department of Pathology and Laboratory Medicine, University of British Columbia, Vancouver, BC, Canada
| | | | - Mohammad Shekari
- Molecular Medicine Research Center, Hormozgan University of Medical Sciences, Bandar Abbas, Iran.
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Ben Nasr H, Bchir S, Ben Anes A, Amri A, Sakhana Y, Benzarti M, Garrouch A, Tabka Z, Chahed K. The -786 T/C polymorphism of NOS3 gene is a susceptibility marker of COPD among Tunisians that correlates with nitric oxide levels and airflow obstruction. Cytokine 2017; 93:66-73. [PMID: 28526204 DOI: 10.1016/j.cyto.2017.05.010] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2016] [Revised: 05/02/2017] [Accepted: 05/10/2017] [Indexed: 11/25/2022]
Abstract
OBJECTIVE The goal of this study was to examine the role of G894T (rs1799983), -786T/C (rs3918161) and a 27 bp variable number of tandem repeats (VNTR) 4B/4A of NOS3 gene on the risk and severity of COPD. METHODS The study included 194 controls and 138 COPD patients. NOS3 G894T, -786T/C and 4B/4A variants were determined by PCR analysis based on the banding pattern on gel electrophoresis. Pulmonary function was evaluated using body plethysmography. The levels of nitric oxide, peroxynitrite and lipid peroxides (T-BARS) were determined using spectrophotometric methods. Levels of serum IL-6, TNF-α and TGFβ were determined by ELISA. RESULTS In case-control studies, both G894T and -786T/C variants were associated with COPD risk. A significantly increased risk of COPD was found with the NOS3894T and -786C alleles (OR:1.93, P=0.001; OR:2.05, P=0.001, respectively). No significant impact of the G894T and 4B/4A SNPs was found on COPD severity, while a significant correlation was retrieved between the NOS3 -786T/C variation and advanced stages (OR: 1.89, P=0.009). In addition, COPD patients with the -786CC genotype exhibited lower FEV1% values in comparison to -786TT carriers (48±3.28 vs. 58.06±2.3, P=0.01, respectively). Patients having the -786CC genotype presented lower plasma levels of nitric oxide and higher T-BARS in comparison to -786TT individuals (173.22±13.4 vs. 228.93±16.8, P=0.01; 1.8±0.15 vs. 1.22±0.15, P=0.01, respectively). CONCLUSION This study provides the first evidence for the association of G894T, -786T/C variants with COPD risk among Tunisians. The -786T/C variation correlates with enhanced airflow limitation. This finding could be related to altered levels of nitric oxide and enhanced lipid peroxides among patients carrying the -786CC genotype.
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Affiliation(s)
- Hela Ben Nasr
- Unité de Recherche UR12ES06, Physiologie de l'Exercice et Physiopathologie: de l'Intégré au Moléculaire "Biologie, Medecine et Santé, Faculté de Medecine Ibn el Jazzar, Sousse, Tunisia; Institut des Sciences Infirmières de Sousse, Tunisia
| | - Sarra Bchir
- Unité de Recherche UR12ES06, Physiologie de l'Exercice et Physiopathologie: de l'Intégré au Moléculaire "Biologie, Medecine et Santé, Faculté de Medecine Ibn el Jazzar, Sousse, Tunisia
| | - Amel Ben Anes
- Unité de Recherche UR12ES06, Physiologie de l'Exercice et Physiopathologie: de l'Intégré au Moléculaire "Biologie, Medecine et Santé, Faculté de Medecine Ibn el Jazzar, Sousse, Tunisia
| | - Asma Amri
- Unité de Recherche UR12ES06, Physiologie de l'Exercice et Physiopathologie: de l'Intégré au Moléculaire "Biologie, Medecine et Santé, Faculté de Medecine Ibn el Jazzar, Sousse, Tunisia
| | - Yosra Sakhana
- Unité de Recherche UR12ES06, Physiologie de l'Exercice et Physiopathologie: de l'Intégré au Moléculaire "Biologie, Medecine et Santé, Faculté de Medecine Ibn el Jazzar, Sousse, Tunisia
| | - Mohamed Benzarti
- Service de Pneumo-Allergologie, CHU Farhat Hached, Sousse, Tunisia
| | | | - Zouhair Tabka
- Unité de Recherche UR12ES06, Physiologie de l'Exercice et Physiopathologie: de l'Intégré au Moléculaire "Biologie, Medecine et Santé, Faculté de Medecine Ibn el Jazzar, Sousse, Tunisia
| | - Karim Chahed
- Unité de Recherche UR12ES06, Physiologie de l'Exercice et Physiopathologie: de l'Intégré au Moléculaire "Biologie, Medecine et Santé, Faculté de Medecine Ibn el Jazzar, Sousse, Tunisia; Département de Biologie, Faculté des Sciences de Sfax, Tunisia.
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Endothelial nitric oxide gene polymorphisms and their association with coronary artery disease in Tunisian population. Anatol J Cardiol 2016; 17:31-36. [PMID: 27443477 PMCID: PMC5324859 DOI: 10.14744/anatoljcardiol.2016.6946] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
OBJECTIVE By releasing mediators, like nitric oxide (NO), vascular endothelium is considered so significant in the process of atherosclerotic . In fact, the major functions of NO consist in inhibiting the activation of platelet, relaxing the muscles (vascular and smooth ones), and modulating the growth and the migration of cells (vascular and smooth ones). Therefore, this process makes the endothelial nitric oxide synthase (NOS3) considerably important because it possesses atheroprotective activity. Polymophisms, rs1808593 (10G/T) as well as rs891512 (G24943A) within NOS3 gene, play major role in the coronary artery disease (CAD) development. The aim of the study is to evaluate the relationship between the 10G/T and G24943A polymorphisms and the CAD among Tunisian individuals. METHODS We included, in this survey, a set of 274 patients suffering from CAD together with 162 normotensive subjects. The PCR-RFLP was applied to analyze the polymorphism of intron 23 (10G/T) gene, while the ASA-PCR was used to analyze the intronic G24943A gene polymorphism. Overall and subgroup analyses were performed. Odds ratio (OR) and 95% confidence interval (CI) were used to evaluate the association between NOS3 10G/T and G24943A polymorphisms as well as CAD risk. Statistical analysis was performed with SPSS V.10. RESULTS The genotype frequencies for G24943A polymorphism differed significantly between the CAD patients and the controls. The former had a frequency of 11.4% for the AA genotype, 34.7% for the GA genotype and 53.9% for the GG genotype. The latter had a frequency of only 2.5% for the AA genotype, 29.7% for the GA genotype and 67.7% for the GG genotype (χ2=7.62; OR=1.79; p=0.006). The CAD patient group showed a significantly-higher frequency of the A allele compared to the controls (0.28 vs. 0.16; χ2=15.20; p<0.001). The odds ratio of CAD for A vs. G allele frequency was statistically significant 1.99 (1.4-2.82) at 95% CI. The genotype distribution for the 3 investigated variants of 10G/T were not significantly different between CAD and control subjects (χ2=1.46; OR=1.72; p=0.22). Whereas, 10G/T has revealed barely allelic (χ2=4.45; OR=2.3; p=0.034) correlation with coronary artery disease Conclusion: The present study was designed so that there would be an association between the CAD and NOS3 polymorphism (G24943A). However, these results have proven that the polymorphism of 10G/T is not associated with CAD in the Tunisian population.
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Wang L, Shen C, Yang S, Chen Y, Guo D, Jin Y, He L, Chen J, Zhao X, Zhao H, Yao Y. Association study of NOS3 gene polymorphisms and hypertension in the Han Chinese population. Nitric Oxide 2015; 51:1-6. [PMID: 26391643 DOI: 10.1016/j.niox.2015.09.004] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2015] [Revised: 09/08/2015] [Accepted: 09/15/2015] [Indexed: 10/23/2022]
Abstract
BACKGROUND Recent studies have reported that NOS3 plays an important role in cardiovascular pathology, whereas the association of NOS3 and hypertension (HT) has been controversial between African Americans and European whites. Here, we aimed to further investigate the genetic effect of unexplored loci at NOS3 on the susceptibility of HT in the Han Chinese population. METHODS AND RESULTS The association of three polymorphisms; rs4496877, rs1808593 and rs3918186 to HT was tested in a case control study that included 2012 HT cases and 2210 controls. Association analysis showed that there was no significant association between rs4496877, rs1808593 and rs3918186 of NOS3 and HT in the whole study population. Stratification analysis indicated that rs3918186 was significantly associated with HT in the ≥55-year-old population (OR = 1.245, 95% CI = 1.010-1.534, P = 0.04). The rs4496877 and rs1808593 were significantly associated with HT in the male population (P = 0.015) and <55-year-old population (P = 0.025), respectively (OR = 3.254, 95% CI = 1.257-8.425 and OR = 1.683, 95% CI = 1.066-2.657, respectively). Quantitative trait analysis showed that there were significant differences in systolic blood pressure (SBP) among the genotypes (AA, AT and TT) of rs3918186 in the non-intervention populations (P = 0.016). GMDR analysis showed that drinking and rs3918186 had significant interaction effects for risk of HT. CONCLUSIONS The findings of this study indicated that the rs4496877, rs1808593 and rs3918186 polymorphisms of NOS3 contribute to the genetic susceptibility of HT and that rs3918186 was associated with SBP in the Chinese population. Age and gender might modify the genetic effect of NOS3 on HT, and drinking significantly interacts with rs3918186.
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Affiliation(s)
- Linhong Wang
- Department of Epidemiology and Biostatistics, School of Public Health, Wannan Medical College, Wuhu 241001, China
| | - Chong Shen
- Department of Epidemiology and Biostatistics, School of Public Health, Nanjing Medical University, Nanjing 210029, China
| | - Song Yang
- Department of Cardiology, Affiliated Yixing People's Hospital of Jiangsu University, People's Hospital of Yixing City, Yixing 214200, China
| | - Yanchun Chen
- Department of Cardiology, Affiliated Yixing People's Hospital of Jiangsu University, People's Hospital of Yixing City, Yixing 214200, China
| | - Daoxia Guo
- Department of Epidemiology and Biostatistics, School of Public Health, Wannan Medical College, Wuhu 241001, China
| | - Yuelong Jin
- Department of Epidemiology and Biostatistics, School of Public Health, Wannan Medical College, Wuhu 241001, China
| | - Lianping He
- Department of Epidemiology and Biostatistics, School of Public Health, Wannan Medical College, Wuhu 241001, China
| | - Jinfeng Chen
- Department of Epidemiology and Biostatistics, School of Public Health, Nanjing Medical University, Nanjing 210029, China
| | - Xianghai Zhao
- Department of Cardiology, Affiliated Yixing People's Hospital of Jiangsu University, People's Hospital of Yixing City, Yixing 214200, China
| | - Hailong Zhao
- Department of Epidemiology and Biostatistics, School of Public Health, Nanjing Medical University, Nanjing 210029, China
| | - Yingshui Yao
- Department of Epidemiology and Biostatistics, School of Public Health, Wannan Medical College, Wuhu 241001, China.
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Kallel A, Sbaï MH, Houman MH, Sediri Y, Ouertani D, Smiti Khanfir M, Ben Ghorbel I, Jemaa R, Kaabachi N. Polymorphisms of the NOS3 gene in Tunisian patients with Behçet's disease. Int J Immunogenet 2015; 42:87-92. [DOI: 10.1111/iji.12176] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2014] [Revised: 11/26/2014] [Accepted: 12/18/2014] [Indexed: 11/29/2022]
Affiliation(s)
- A. Kallel
- Université de Tunis El Manar; Research Laboratory LR99ES11; Department of Biochemistry; Rabta University Hospital; Tunis Tunisia
| | - M. H. Sbaï
- Université de Tunis El Manar; Research Laboratory LR99ES11; Department of Biochemistry; Rabta University Hospital; Tunis Tunisia
| | - M. H. Houman
- Behçet's Disease Research Unit 02/UR/08-15; Department of Internal Medicine; Rabta University Hospital; Tunis Tunisia
| | - Y. Sediri
- Université de Tunis El Manar; Research Laboratory LR99ES11; Department of Biochemistry; Rabta University Hospital; Tunis Tunisia
| | - D. Ouertani
- Behçet's Disease Research Unit 02/UR/08-15; Department of Internal Medicine; Rabta University Hospital; Tunis Tunisia
| | - M. Smiti Khanfir
- Behçet's Disease Research Unit 02/UR/08-15; Department of Internal Medicine; Rabta University Hospital; Tunis Tunisia
| | - I. Ben Ghorbel
- Behçet's Disease Research Unit 02/UR/08-15; Department of Internal Medicine; Rabta University Hospital; Tunis Tunisia
| | - R. Jemaa
- Université de Tunis El Manar; Research Laboratory LR99ES11; Department of Biochemistry; Rabta University Hospital; Tunis Tunisia
| | - N. Kaabachi
- Université de Tunis El Manar; Research Laboratory LR99ES11; Department of Biochemistry; Rabta University Hospital; Tunis Tunisia
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Kallel A, Sbaï MH, Sediri Y, Abdessalem S, Mourali MS, Feki M, Mechmeche R, Jemaa R, Kaabachi N. Polymorphisms of the NOS3 gene and risk of myocardial infarction in the Tunisian population. Cytokine 2013; 64:646-51. [PMID: 24095258 DOI: 10.1016/j.cyto.2013.09.005] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2013] [Revised: 07/29/2013] [Accepted: 09/04/2013] [Indexed: 11/27/2022]
Abstract
Controversial results regarding the association of eNOS gene (NOS3) polymorphisms with myocardial infarction (MI) have been reported. This study investigated the relationship of the -786T>C (rs2070744), 894G>T (rs1799983) and 4a4b polymorphisms of the NOS3 gene with the presence of MI in the Tunisian population. In addition, we also examined the association of NOS3 gene haplotypes with MI in Tunisian subjects. A total of 303 patients with MI and 225 controls were included in the study. The 894G>T and -786T>C single nucleotide polymorphisms were analyzed by PCR-RFLP, and 4a4b polymorphism just for PCR. There was significant linkage disequilibrium between the three NOS3 polymorphisms (p<0.0001). The genotype distribution and allele frequency of NOS3 4a4b, but not -786T>C and 894G>T, polymorphism was significantly different between MI patients and controls. The univariate logistic regression analysis showed a significant association of the 4a4b polymorphism and MI according to co-dominant, dominant and recessive models (co-dominant model OR: 4.38, 95%CI: 1.24-15.41; p=0.021, dominant model OR: 1.66, 95%CI: 1.14-2.42); p=0.007, and recessive model OR: 3.85, 95%CI: 1.10-13.47; p=0.035). The multivariate analysis, adjusted for traditional cardiovascular risk factors, revealed that the NOS3 4a4a genotype was an independent predisposing factor to MI, according to the models considered. In addition, a haplotype 7 (C-T-4a), (OR=12.05, p=0.010) was a risk factor of MI after controlling for classical risk factors. These finding suggest that the 4a4b polymorphism of the NOS3 gene was associated with MI in Tunisian patients.
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Affiliation(s)
- Amani Kallel
- Université de Tunis El Manar, Hôpital la Rabta, Service de Biochimie, LR99ES11, 1007 Tunis, Tunisie
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Between candidate genes and whole genomes: time for alternative approaches in blood pressure genetics. Curr Hypertens Rep 2012; 14:46-61. [PMID: 22161147 DOI: 10.1007/s11906-011-0241-8] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Blood pressure has a significant genetic component, but less than 3% of the observed variance has been attributed to genetic variants identified to date. Candidate gene studies of rare, monogenic hypertensive syndromes have conclusively implicated several genes altering renal sodium balance, and studies of essential hypertension have inconsistently implicated over 50 genes in pathways affecting renal sodium balance and other functions. Genome-wide linkage scans have replicated numerous quantitative trait loci throughout the genome, and over 50 single nucleotide polymorphisms (SNPs) have been replicated in multiple genome-wide association studies. These studies provide considerable evidence that epistasis and other interactions play a role in the genetic architecture of blood pressure regulation, but candidate gene studies have limited scope to test for epistasis, and genome-wide studies have low power for both main effects and interactions. This review summarizes the genetic findings to date for blood pressure, and it proposes focused, pathway-based approaches involving epistasis, gene-environment interactions, and next-generation sequencing to further the genetic dissection of blood pressure and hypertension.
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