Genetic Polymorphisms and Genetic Risk Scores Contribute to the Risk of Coronary Artery Disease (CAD) in a North Indian Population.

Coronary artery disease (CAD) is the leading cause of death in India. Many genetic polymorphisms play a role in regulating oxidative stress, blood pressure and lipid metabolism, contributing to the pathophysiology of CAD. This study examined the association between ten polymorphisms and CAD in the Jat Sikh population from Northern India, also considering polygenic risk scores. This study included 177 CAD cases and 175 healthy controls. The genetic information of GSTM1 (rs366631), GSTT1 (rs17856199), ACE (rs4646994), AGT M235T (rs699), AGT T174M (rs4762), AGTR1 A1166C (rs5186), APOA5 (rs3135506), APOC3 (rs5128), APOE (rs7412) and APOE (rs429358) and clinical information was collated. Statistical analyses were performed using SPSS version 27.0 and SNPstats. Significant independent associations were found for GST*M1, GST*T1, ACE, AGT M235T, AGT T174M, AGTR1 A1166C and APOA5 polymorphisms and CAD risk (all p < 0.05). The AGT CT haplotype was significantly associated with a higher CAD risk, even after controlling for covariates (adjusted OR = 3.93, 95% CI [2.39-6.48], p < 0.0001). The APOA5/C3 CC haplotype was also significantly associated with CAD (adjusted OR = 1.86, 95% CI [1.14-3.03], p < 0.05). A higher polygenic risk score was associated with increased CAD risk (adjusted OR = 1.98, 95% CI [1.68-2.34], p < 0.001). Seven polymorphisms were independently associated with an increase in the risk of CAD in this North Indian population. A considerable risk association of AGT, APOA5/C3 haplotypes and higher genetic risk scores is documented, which may have implications for clinical and public health applications.

The Association of M235T Genetic Polymorphism in Angiotensinogen Gene and Other Non-Genetic Factors with Essential Hypertension among Jordanian Patients.

BACKGROUND: Hypertension, characterized by elevated pressure, poses a significant health risk. Recent studies in Jordan highlight high hypertension rates, emphasizing the need for genetic investigations to comprehend essential hypertension determinants. The AGT gene, part of the Renin Angiotensin System, is linked to blood pressure regulation. Limited information exists on the frequency of this polymorphism among Jordanian hypertensive patients. AIMS: This study explores the association between the AGT M235T polymorphism and essential hypertension in Jordan. METHODS: A cross-sectional study with 435 participants (199 hypertensive, 236 non-hypertensive) was conducted at the University of Jordan Hospital. Blood pressure was measured, and genetic analysis of the AGT M235T polymorphism was completed using the PCR-RFLP technique. Chi-square and t-tests were used for comparisons using SPSS software. RESULTS: Hypertensive patients exhibited significantly higher weight, BMI, and blood pressure. Genotyping results showed no significant difference (p > 0.05, Chi-square) in AGT M235T polymorphism distribution between control and patient groups. In addition, allele frequencies showed comparable patterns (p > 0.05, Chi-square). All genotype frequencies showed no deviation from the Hardy-Weinberg equation (p > 0.05, Chi-square). CONCLUSIONS: The AGT M235T genetic polymorphism is not more prevalent among hypertensive patients in Jordan, although the average weight and BMI among hypertensive patients is higher than the non-hypertensive participants. Obesity can be addressed as a potential risk factor for essential hypertension in Jordan. In addition, it is recommended to find out the influence of the AGT M235T genetic polymorphism on the response of antihypertensive drugs among hypertensive patients in Jordan.

Angiotensinogen, Angiotensin-Converting Enzyme, and Chymase Gene Polymorphisms as Biomarkers for Basal Cell Carcinoma Susceptibility.

INTRODUCTION: The intake of angiotensin-converting enzyme (ACE) inhibitors and specific antagonists of angiotensin II receptors, widely used as antihypertensive drugs, significantly reduces the risk of developing basal cell carcinoma (BCC), highlighting the possible tumorigenic role of angiotensin II (AngII). We present here the investigated genetic association between the development of BCC and functional DNA polymorphisms M235T, I/D, and A1903G in the genes of angiotensinogen (AGT), angiotensin-converting enzyme (ACE), and chymase (CMA1), which mediate AngII production levels. METHODS: DNA samples of 203 unrelated Greeks were studied, including 100 patients with BCC and 103 matched healthy controls. RESULTS: The MT genotype of the AGT-M235T polymorphism was significantly more prevalent in the patient group (78.0%) versus the healthy control group (28.3%; p < 0.001). The DD genotype of the ACE-I/D polymorphism was also increased in BCC patients (72.8%) compared to controls (46.2%; p = 0.001). The heterozygous AG genotype of CMA1-A1903G was significantly more frequent in the BCC group (86%) than in the healthy controls (50.5%; p < 0.001). CONCLUSIONS: The MT, DD, and AG genotypes of the AGT- M235T, ACE-I/D, and CMA1-A1903G polymorphisms, respectively, were significantly increased in frequency within the group of cancer patients compared to the healthy controls. All three genotypes correspond to increased enzyme levels or activity and result in increased levels of AngII; therefore, they may be potentially utilized as reliable biomarkers associated with an individual's increased risk for BCC development.

Pertinence between risk of preeclampsia and the renin-angiotensin-aldosterone system (RAAS) gene polymorphisms: an updated meta-analysis based on 73 studies.

The aetiological mechanism of preeclampsia (PE) is unclear exactly, so we attempted to investigate the association between susceptibility to preeclampsia and renin-angiotensin-aldosterone system (RAAS) gene polymorphisms to explore the aetiology in terms of genetics. A systematic search was performed in electronic databases to identify relevant studies. Eventually 73 studies were enrolled, odds ratios were generated by 5 genetic models. In overall analysis, significant associations were detected for AGT M235T, AT1R A1166C and CYP11B2 C344T whereas negative correlation was shown for AGT T174M. As stratified by race and geography, AGT 235T allele and AT1R 1166C allele increased preeclampsia risk and AGT T174M was justified uncorrelated with preeclampsia. Our meta-analysis illustrated that AGT 235T allele and AT1R 1166C allele increased and CYP11B2 344T allele decreased preeclampsia risk while AGT T174M polymorphism did not change preeclampsia risk. Hence, pregnant women carrying high-risk genotypes need strengthened management to prevent and early identification of preeclampsia.

Genetic Polymorphism in Angiotensinogen and Its Association with Cardiometabolic Diseases.

Angiotensinogen (AGT) is one of the most significant enzymes of the renin-angiotensin-aldosterone system (RAAS) which is involved in the regulation and maintenance of blood pressure. AGT is involved in the production of angiotensin I which is then converted into angiotensin II that leads to renal homeostasis. However, various genetic polymorphisms in AGT have been discovered in recent times which have shown an association with various diseases. Genetic polymorphism increases the level of circulating AGT in blood which exaggerates the effects produced by AGT. The associated diseases occur due to various effects produced by increased AGT levels. Several cardiovascular diseases including myocardial infarction, coronary heart disease, heart failure, hypertrophy, etc. are associated with AGT polymorphism. Other diseases such as depression, obesity, diabetic nephropathy, pre-eclampsia, and liver injury are also associated with some variants of AGT gene. The most common variants of AGT polymorphism are M235T and T174M. The two variants are associated with many diseases. Some other variants such as G-217A, A-6G, A-20C and G-152A, are also present but they are not as significant as that of M235T and T174M variants. These variants increase the level of circulating AGT and are associated with prevalence of different diseases. These diseases occur through various pathological pathways, but the initial reason remains the same, i.e., increased level of AGT in the blood. In this article, we have majorly focused on how genetic polymorphism of different variants of AGT gene is associated with the prevalence of different diseases.

Association Between AGT M235T and Left Ventricular Mass in Vietnamese Patients Diagnosed With Essential Hypertension.

Background: Increasing left ventricular mass in hypertensive patients is an independent prognostic marker for adverse cardiovascular outcomes. Genetic factors have been shown to critically affect left ventricular mass. AGT M235T is one of the genetic polymorphisms that may influence left ventricular mass due to its pivotal role in the regulation of plasma angiotensinogen level as well as hypertension pathophysiology in Asian populations. Currently, how M235T affects left ventricular mass is not well-described in Vietnamese hypertensive patients. This study aimed to investigate the association between M235T and left ventricular mass in Vietnamese patients diagnosed with essential hypertension. Materials and Methods: AGT M235T genotyping and 2D echocardiography were performed on 187 Vietnamese subjects with essential hypertension. All the ultrasound parameters were obtained to calculate the left ventricular mass index according to the American Society of Echocardiography and the European Association of Cardiovascular Imaging 2015 guidelines. Other clinical characteristics were also recorded, including age, gender, duration of hypertension, hypertensive treatment, lifestyle, renal function, fasting plasma glucose, and lipid profile. Results: MT and TT genotypes were determined in 30 and 157 subjects, respectively. AGT M235T genotype, duration of hypertension, body mass index, and ejection fraction statistically affected the left ventricular mass index, which was significantly greater in TT compared to MT carriers after adjusting for confounding factors. Conclusion: The TT genotype of AGT M23T was associated with greater left ventricular mass in Vietnamese patients diagnosed with essential hypertension.

A study of the association between angiotensinogen (AGT) gene polymorphism (M235T) and preeclampsia in Thai pregnant women.

AGT M235T gene polymorphism may cause increased blood pressure in preeclampsia in pregnancy; however, the evidence remains controversial. This study investigated the association between AGT M235T and preeclampsia in Thai pregnant women. A case-control study was conducted to compare the distributions of AGT M235T genotypes and alleles between 142 normotensive pregnancies as controls and 61 preeclampsia pregnancies as cases in a tertiary-care university hospital in Chiang Mai, Thailand. The results show that the distribution of AGT M235T genotypes (MM, MT and TT) of both groups were not significantly different (preeclampsia: 0.0, 16.4, 83.6%; control: 2.1, 22.5, 75.4%, respectively; p = .30). Additionally, there was no statistical difference in the distribution of AGT M235T alleles (M and T alleles) (preeclampsia: 8.2 and 91.8% versus control: 13.4 and 86.6%, respectively; p = .14). In this study, the distributions of AGT M235T were not different in both groups. Therefore, AGT M235T polymorphism may not play a significant role in preeclampsia pathophysiology in Thai population.Impact statementWhat is already known on this subject? Preeclampsia is one of the major complications during pregnancy; it significantly affects maternal and perinatal morbidity and mortality. Effort has been made to find markers and predictors that are associated with the pathophysiology of preeclampsia. AGT M235T gene polymorphism may cause increased blood pressure in preeclampsia pregnancy; however, evidences are still controversial.What do the results of this study add? We conducted a case-control study to compare the distributions of AGT M235T genotypes and alleles between 142 normotensive pregnancies as controls and 61 preeclampsia pregnancies as cases. The results show that preeclamptic women are more likely to deliver at an earlier gestational age and have a smaller baby in comparison with the normotensive group. In addition, women with preeclampsia had a higher chance of having an operative delivery and caesarean section. However, the distribution of AGT M235T polymorphism of preeclampsia women and the control group were not significantly different.What are the implications of these findings for clinical practice and/or further research? AGT M235T polymorphism may not play a significant role in preeclampsia pathophysiology in Thai population.

Relationship between M235T and T174M polymorphisms in angiotensin gene and atrial fibrillation in Uyghur and Han populations of Xinjiang, China.

OBJECTIVE: To elucidate the association between angiotensin gene (AGT) M235T and T174M genetic polymorphisms in Han and Uyghur patients with atrial fibrillation (AF) in Xinjiang, China. METHODS: 100 cases of patients with AF of Han and 100 cases of patients with AF of Uyghur were selected as the experimental group, and 100 cases of patients with non-AF of Uyghur and non-AF of Han were selected as the control group. We amplified the AGT M235T site and AGT T174M site by PCR in 4 groups of patients, verified the polymorphism of the sites by gene sequencing, and compared their differences in each group. RESULTS: The high risk factors for AF such as sex, left atrial diameter (LAD), right atrial diameter (RAD), and coronary heart disease were significantly different between the Han case group and the control group (P < 0.05). There were significant differences in age, LAD, RAD, coronary heart disease and smoking as contributors to AF between Uyghur case group and control group (P < 0.05). The genotype frequency distribution of AGT M235T and AGT T174M loci in the AF group and control group of Han and Uyghur was in accordance with Hardy-Weinberg equilibrium law test. There was a significant difference in genotype frequency and allele frequency of AGT M235T locus between Han group, Uyghur AF group and control group (P < 0.05). CONCLUSION: The AGT M235T and AGT T174M loci were associated with the occurrence of atrial fibrillation in the Han and Uyghur ethnic groups in Xinjiang.

Association Between M235T-AGT and I/D-ACE Polymorphisms and Carotid Atheromatosis in Hypertensive Patients: A Cross-Sectional Study.

BACKGROUND/AIM: The renin-angiotensin-aldosterone system (RAAS) may be implicated in carotid atheromatosis (CA) development. We aimed to assess the relationship of M235T-angiotensinogen (AGT) and insertion/deletion of angiotensin conversion enzyme (I/D-ACE) genotypes with CA in patients with essential hypertension (EHT). PATIENTS AND METHODS: We determined the M235T-AGT and I/D-ACE genotypes, using PCR-RFLP methods, in 162 hypertensive subjects from three tertiary regional medical centers. The relationship between the studied RAAS gene polymorphisms and CA was assessed by multiple logistic regressions. RESULTS: Hypertensive patients carrying the MT/TT235-AGT and MT235-AGT genotypes had a 2.17-fold (p=0.033) and 2.24-fold (p=0.036) increased risk to develop CA, respectively. These genotypes, MT/TT 235-AGT (OR=2.17, p=0.033) and MT235-AGT (OR=2.24, p=0.036), remain independent risk factors for CA in hypertensive patients according to the multivariate model. CONCLUSION: There is a statistically significant association between M235T-AGT and CA, when adjusting for several confounders and controlling for hypertension.

IgE-Mediated Systemic Anaphylaxis And Its Association With Gene Polymorphisms Of ACE, Angiotensinogen And Chymase.

BACKGROUND: The renin-angiotensin system (RAS) protects the circulation against sudden falls in systemic blood pressure via generation of angiotensin II (AII). Previously, we demonstrated that patients with anaphylaxis involving airway angioedema and cardiovascular collapse (AACVS) had significantly increased "I" gene polymorphisms of the angiotensin-converting-enzymes (ACE). This is associated with lower serum ACE and AII levels and was not seen in anaphylaxis without collapse nor atopics and healthy controls. OBJECTIVES: To examine the angiotensinogen (AGT-M235T) and chymase gene (CMA-1 A1903G) polymorphisms in these original subjects. METHOD: 122 patients with IgE-mediated anaphylaxis, 119 healthy controls and 52 atopics had polymorphisms of the AGT gene and chymase gene examined by polymerase chain reactions and gel electrophoresis. Their previous ACE genotypes were included for the analysis. RESULTS: AGT-MM genes (associated with low AGT levels) were significantly increased in anaphylaxis (Terr's classification). When combined with ACE, anaphylaxis showed increased MM/II gene pairing (p<0.0013) consistent with lower RAS activity. For chymase, there was increased pairing of MM/AG (p<0.005) and AG/II and AG/ID (p<0.0073) for anaphylaxis consistent with lower RAS activity. A tri-allelic ensemble of the 6 commonest gene combinations for the healthy controls and anaphylaxis confirmed this difference (p=0.0001); for anaphylaxis, genes were predominately MM/AG/II or ID, while healthy controls were DD/MT/AG or GG patterns. CONCLUSION: Our gene polymorphisms show lower RAS activity for anaphylaxis especially AACVS. Animal models of anaphylaxis are focused on endothelial nitric oxide (eNO) which is shown to be the mediator of fatal shock and prevented by eNO-blockade. The interaction of AII and eNO controls the microcirculation in man. High serum AII levels reduce eNO activity, so higher RAS-activity could protect against shock. Our data shows low RAS activity in anaphylaxis especially AACVS, suggesting the influence of these genes on shock are via AII levels and its effects on eNO.

Evaluation of Angiotensinogen M235T and T174M Polymorphisms, Demographic and Clinical Factors in New-Onset Diabetes after Liver Transplantation in Iranian Patients.

BACKGROUND: New-onset diabetes after transplantation (NODAT) is a serious complication which runs the risk of infections, morbidity and mortality. OBJECTIVE: To evaluate M235T and T174M polymorphisms of angiotensinogen gene along with some demographic and clinical factors including age; sex; body mass index (BMI); model for end-stage liver disease (MELD) score; prednisolone, mycophenolate mofetil and tacrolimus dose; and serum level in NODAT among liver recipients. METHODS: In this study 115 patients (53 with and 62 without NODAT) who had no history of diabetes before the transplantation were investigated. Furthermore, 80 randomly selected apparently healthy people (no transplantation) were used as the control group. Two angiotensinogen polymorphisms (M235T and T174M) were studied using polymerase chain reaction restriction fragment length polymorphism (PCR-RFLP). RESULTS: Patients included 68 (59.1%) females and 47 (40.9%) males; they had a mean±SD age of 37.4±16.9 years. The M allele frequency was 55.7% (n=128) in M235T and 20.0% (n=46) in T174M polymorphisms. Binary logistic regression analysis confirmed that age (p=0.005), prednisolone dose (p<0.001) and mutated M235T polymorphism (p=0.003) were independent risk factors. CONCLUSION: Presence of M235T T allele may significantly (p<0.001) increase the NODAT risk, and increase the likelihood of developing end-stage liver disease (p=0.003). T174M T allele had a significantly (p=0.007) higher frequency in NODAT group.

Gene polymorphisms of angiotensin-converting enzyme and angiotensinogen and risk of idiopathic ischemic stroke.

OBJECTIVE: The renin-angiotensin system (RAS) is a hormonal signaling mechanism implicated in the atherosclerosis and regulation of blood pressure. Angiotensin-converting enzyme (ACE) a key enzyme in the RAS, plays important roles in vascular remodeling atherosclerosis, and ischemic stroke. The aim of this study was to examine the possible contribution of the I/D in the ACE gene, M235T and T174M in the angiotensinogen (AGT) gene polymorphisms with ischemic stroke in young Mexican population. MATERIALS AND METHODS: A total of 224 patients with diagnosis of idiopathic ischemic stroke ≤45 years of age, and 224 controls matched by age and gender, were recruited from 2006 and 2016. The I/D, M235T and T174M polymorphisms were determined in all participants by PCR-RFLP. RESULTS: There was a significant difference in the M235T genotype distribution (p = 0.01) and allele frequency between two groups (p = 0.01). Also, we found a significant difference in the T174M genotype distribution (p = 0.01) and the allele frequency between groups; (p = 0.02). In contrast, in I/D polymorphism, there was a similar genotype distribution; (p = 0.20) and allele distribution (p = 0.20). There were independent factors for ischemic stroke: M235T and T174M polymorphisms, smoking, hypertension, and familial history of atherothrombotic disease. The AGT levels were increased in the group of patients with stroke compared with the control group, but the AGT levels were not influenced by the allele or genotype in each polymorphism. CONCLUSIONS: The M235T and T174M polymorphisms represented an increased risk for stroke in young Mexican individuals. In contrast, the I/D was not associated with in the same group of patients. The AGT levels were higher in the acute phase of stroke, but it was not determined by the polymorphisms.

Renin-Angiotensin-Aldosterone System Gene Polymorphisms and Type 2 Diabetic Nephropathy in Asian Populations: An Updated Meta-analysis.

BACKGROUND: The association of polymorphisms in the renin-angiotensin-aldosterone system candidate genes, namely Angiotensin-Converting Enzyme (ACE) Insertion/Deletion (I/D), Angiotensinogen (AGT) M235T and Angiotensin II Receptor Type 1 (AGTR1) A1166C with Diabetic Nephropathy (DN) has been studied for decades. OBJECTIVE: This meta-analysis aimed to assess the updated pooled effects of these polymorphisms with DN among Asian populations with type 2 diabetes mellitus. METHODS: The PubMed electronic database was searched without duration filter until August 2017 and the reference list of eligible studies was screened. The association of each polymorphism with DN was examined using odds ratio and its 95% confidence interval based on dominant, recessive and allele models. Subgroup analyses were conducted based on region, DN definition and DM duration. RESULTS: In the main analysis, the ACE I/D (all models) and AGTR1 A1166C (dominant model) showed a significant association with DN. The main analysis of the AGT M235T polymorphism did not yield significant findings. There were significant subgroup differences and indication of significantly higher odds for DN in terms of DM duration (≥10 years) for ACE I/D (all models), AGT M235T (recessive and allele models) and AGTR1 A1166C (recessive model). Significant subgroup differences were also observed for DN definition (advanced DN group) and region (South Asia) for AGTR1 A1166C (recessive model). CONCLUSION: In the Asian populations, ACE I/D and AGTR1 A1166C may contribute to DN susceptibility in patients with T2DM by different genetic models. However, the role of AGT M235T needs to be further evaluated.

Angiotensinogen M235T Gene Polymorphism is a Genetic Determinant of Cerebrovascular and Cardiopulmonary Morbidity in Adolescents with Sickle Cell Disease.

BACKGROUND: Cerebrovascular stroke is a common critical complication of sickle cell disease (SCD). Angiotensinogen (AGT) M235T gene polymorphism is associated with risk of ischemic stroke and cardiovascular disease. AIM: We investigated the potential association between angiotensinogen M235T gene polymorphism and susceptibility to cerebrovascular and cardiopulmonary complications in adolescents with SCD. METHODS: Forty-six patients with SCD in steady state were studied stressing on history of stroke, hydroxyurea/chelation therapy, hematological profile, and echocardiographic findings. Polymerase chain reaction-based restriction fragment length polymorphism analysis was used to detect AGT M235T gene polymorphism. Fifty sex- and age-matched healthy controls were enrolled for assessment of M235T gene polymorphism pattern. RESULTS: The distribution of AGT M235T gene polymorphism was similar between SCD patients and healthy controls. The frequency of T allele of AGT M235T gene polymorphism (TT and MT genotypes) was significantly higher among patients with history of manifest stroke (P < .001). Patients with TT and MT genotypes had higher incidence of cardiopulmonary complications (P = .041) as well as higher percentage of HbS (P < .001) and lower hemoglobin level (P = .008) compared with those with MM genotype. Serum ferritin, liver iron concentration, and cardiac T2* were not related to T alleles or genotypes. Logistic regression analysis revealed that M235T genotype was a significant independent factor related to the occurrence of stroke among patients with SCD (Odds Ratio 14.05, 95% confidence interval 3.82-28.91; P = .001). CONCLUSION: AGT M235T gene polymorphism may represent a genetic modifier to vascular morbidities in Egyptian patients with SCD.

Neuromarkers of the common angiotensinogen polymorphism in healthy older adults: A comprehensive assessment of white matter integrity and cognition.

The common angiotensinogen (AGT) M268T polymorphism (rs699; historically referred to as M235T) has been identified as a significant risk factor for cerebrovascular pathologies, yet it is unclear if healthy older adults carrying the threonine amino acid variant have a greater risk for white matter damage in specific fiber tracts. Further, the impact of the threonine variant on cognitive function remains unknown. The present study utilized multiple indices of diffusion tensor imaging (DTI) and neuropsychological assessment to examine the integrity of specific white matter tracts and cognition between individuals with homozygous genotypes of M268T (MetMet n=27, ThrThr n=27). Differences in subcortical hyperintensity (SH) volume were also examined between groups. Results indicated that the threonine variant was associated with significantly reduced integrity in the superior longitudinal fasciculus (SLF) and the cingulate gyrus segment of the cingulum bundle (cingulum CG) compared to those with the methionine variant, and poorer cognitive performance on tests of attention/processing speed and language. Despite these associations, integrity of these tracts did not significantly mediate relationships between cognition and genetic status, and SH did not differ significantly between groups. Collectively our results suggest that the threonine variant of M268T is a significant risk factor for abnormalities in specific white matter tracts and cognitive domains in healthy older adults, independent of SH burden.

AGT M235t polymorphism and heart failure in a cohort of Tunisian population: diagnostic and prognostic value.

Activity of the renin-angiotensin Aldosterone system is increased in patients with heart failure (HF). The Angiotensinogen gene and specifically M235T polymorphism has been linked to susceptibility to hypertension, coronary heart disease and atrial fibrillation. Its role in heart failure is not yet sufficiently demonstrated. The aim of the present study was to assess the association between rs699 (M235T) polymorphism and heart failure in terms of diagnosis and prognosis. We included all patients over 20 years old consulting in the Emergency Department for acute dyspnea. According to the results of the B-type natriuretic peptide (BNP level), patients were divided into two groups: HF and non-HF group. DNA study was performed for all subjects and their genotypes were identified as TT, CT or CC. Mortality was followed for one year. We included 234 patients. We found the diagnosis of HF in 73 patients out of 160 (45%). Our results showed that the frequency of the T allele was higher in HF group patients than in non-HF group (69% vs. 33%, P<0.01). Patients carrying the TT and CT genotypes had a higher proportion of HF than those carrying the CC genotype (respectively 53% and 31% vs. 15%, P<0.01). According to multivariate analysis, TT genotype presented the highest risk of HF (OR=4.9 95% CI: 2.12-9.1) and the highest risk of death (OR=6.45 95% CI: 3.6-16.4) compared to the other two genotypes. The current study suggests that M235T polymorphism might be associated with increased risk of both HF and death.

Association study between some renin-angiotensin system gene variants and essential hypertension in a sample of Algerian population: case control study.

Essential hypertension is an important risk factor for the development of cardiovascular disease. We aim in this study to analyse the relationship between AGT M235T gene variant and ACE I/D gene variant with essential hypertension in a sample of the Algerian population of the Oran city. A case-control study has been performed in 145 subjects including; 75 hypertensives and 70 controls from Algerian population of Oran city. Polymerase chain reaction (PCR) combined with restrictive fragment length polymorphism (RFLP) was used to detect the M235T variant of angiotensinogen (AGT) gene and a nested PCR to determine ACE I/D gene variant. The genotypic and allelic distribution of the M235Tvariant of the AGT gene did not differ in hypertensives and normotensives group (X(2) =7.81, P<0.05; X(2) =4.67, respectively) thus there was no association between the T allele and hypertension (OR=1.64; 95%CI [1.01-2.69]). The genotypic and allelic frequencies of the ACE I/D variant did differ significantly between hypertensives and controls (X(2)=13.98, P<0.05; X(2) =12.66, P<0.05, respectively) where a significant association between the D allele of the ACE I/D gene and essential hypertension has been observed (OR=0.46; 95%CI [0.27-0.75]). We reported a high prevalence of the D and T allele in hypertensives female. This study shows that the M235T variant of the AGT gene is not associated with essential hypertension while a significant association has been reported with the D allele in this sample of Algerian population of the Oran city.

Correlation between renin-angiotensin system gene polymorphisms and essential hypertension in the Chinese Yi ethnic group.

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.

Angiotensinogen gene M235T and angiotensin II-type 1 receptor gene A/C1166 polymorphisms in chronic obtructive pulmonary disease.

Chronic obstructive pulmonary disease (COPD) occurs irreversibly and is characterized by progressive airflow obstruction. Renin angiotensin system (RAS) has many different key enzymes and receptors that have a role for different systemic processes. We aimed to determine genotype and allele frequencies of angiotensinogen (AGT) M235T and angiotensin II-type 1 receptor (AT1-R) A/C1166 polymorphisms in patients with COPD. This study was performed on 56 unrelated COPD patients and 29 healthy subjects. DNA samples for each individual were isolated from peripheral blood by phenol/chloroform method, analyzed by polymerase chain reaction and enzymatic digestion methodologies. The distribution for each of AGT genotypes were 23.2% for MM (13), 75.0% for MT (42) and 1.8% for TT (1) in the COPD group; 37.9% for MM (11), 34.5% for MT (10) and 27.6% for TT (8) in the control group. The distribution of AGT genotypes was found significantly different between groups (X(2) = 18.604; df = 2; P = 0.000). The frequencies for each of the AT1-R genotypes were found as 53.6% for AA (30), 42.9% for AC (24), 3.6% for CC (2) in the COPD group; 55.2% for AA (16), 41.4% for AC (12) and 3.4% for CC (1) in the control group. The distribution of AT1-R genotypes did not change significantly between groups. Allele frequencies of interested genes were not significantly different between groups. We suggest that AGT polymorphism may play a role for the development of COPD. We believe these data can be served for large scale population genetics research, considering the frequency of AGT and AT1-R genes and alleles in COPD patients in the Turkish population.

The M235T polymorphism in the angiotensinogen gene and atrial fibrillation: A meta-analysis.

OBJECTIVE: The M235T polymorphism in the angiotensinogen gene has been reported to be associated with the development of atrial fibrillation (AF).However, results from observational studies are conflicting. METHODS: PubMed, google scholar and China National Knowledge Infrastructure database(2000.1-2013.4) were searched for eligible articles; four separate studies with 2580 subjects on the relationship between M235T polymorphism and AF were analyzed by meta-analysis. The associations between M235T polymorphism and AF risk were estimated by pooled odds ratio (OR) and 95% confidence interval (CI) using a fixed or random-effects model. RESULTS: There was a significant association between M235T polymorphism and AF. The pooled OR for the recessive model in the total population was 2.17 (95% CI: 1.39-3.38, I(2)=0%). In a subgroup analysis by nationality, the pooled OR for TT vs. MM genotype was 0.55 (95% CI: 0.32-0.95, I(2)=0%) and the pooled OR for the recessive model was 1.86 (95% CI: 1.08-3.20, I(2)=0%) in Asians. CONCLUSIONS: The current meta-analysis suggested that the M235T polymorphism in the angiotensinogen gene might be related to the increased risk of AF in Asians. Conclusive evidence on the effects of the variants in AF should be addressed in further studies.