Association of angiotensin II type-1 receptor A1166C gene polymorphism with the susceptibility of end-stage renal disease

Abstract

Association between angiotensin II type-1 receptor (AT1R) A1166C gene polymorphism and end-stage renal disease (ESRD) risk is still controversial. This meta-analysis was performed to evaluate the association of AT1R A1166C gene polymorphism with ESRD susceptibility. The search was performed in the databases of PubMed, Embase and Cochrane Library as of 1 May 2012, and the eligible investigations were recruited for this meta-analysis. Nineteen literatures were identified for the analysis of association between AT1R A1166C gene polymorphism and ESRD susceptibility. There was no association between AT1R A1166C gene polymorphism and ESRD susceptibility for overall populations, Caucasians, Asians and Turkish population. Interestingly, CC genotype was associated with a higher risk of ESRD in Africans (OR?=?3.36, 95% CI: 1.42–7.99, p?=?0.006). However, C allele and AA genotype were not associated with the ESRD risk in African population. In conclusion, CC genotype might be a risk factor for the ESRD susceptibility in African population. However, more case-control association investigations on larger, stratified populations are required in the future.     

Polymorphism of gene encoding vascular angiotensin II receptor and microangiopathies in patients with insulin-dependent diabetes mellitus

Polymorphism A1166C of the AT1R gene encoding angiotensin vascular receptor [replacement of C (cytosine) for A (adenine)) at position 1166] was compared in patients with insulin-dependent diabetes mellitus (IDDM) complicated by diabetic nephropathy (DN) and in noncomplicated patients (n = 27 and n = 41, respectively) and also in patients with IDDM complicated by diabetic retinopathy (DR) and in correspondent noncomplicated individuals (n = 30 and n = 44, respectively). The frequency of AT1R gene alleles and genotypes in patients with IDDM complicated by DN did not differ significantly from that observed in patients with noncomplicated IDDM. In contrast, in patients with IDDM complicated by retinopathy, a significant decrease in the content of A allele (68.3% against 82.6%) and a significant increase in the content of C allele (31.7% against 17.4%) was found as compared with the control group. Thus, in the Moscow population, A1166C polymorphism of the AT1R gene is not associated with diabetic renal complications but indeed associated with diabetic retinal complications. C allele is a risk factor of DR (the relative risk, RR, is equal to 2.17), and A allele is, in contrast, a protective factor against early retinopathy development (RR is equal to 0.49).     

Apolipoprotein A5 polymorphisms in Turkish population: association with serum lipid profile and risk of ischemic stroke

Atherosclerosis, a major cause of ischemic stroke, may be associated with variability of triglyceride (TG) levels. Apolipoprotein A5 (APOA5) genetic polymorphisms are associated with altered TG levels. The objective of this study was to investigate the coding region polymorphisms S19W (rs3135506) and G185C (rs2075291) and the promoter region polymorphism ?1131T>C (rs662799) of the APOA5 gene as risk factors for ischemic stroke in Turkish population. Study group consisted of 272 ischemic stroke patients and 123 controls. Genotypes were determined by real-time polymerase chain reaction (PCR) for S19W and PCR-restriction fragment length polymorphism analysis (PCR–RFLP) for ?1131T>C and G185C. 19W allele frequency was 0.090 in stroke patients and 0.062 in controls (P = 0.191). Minor allele frequencies of ?1131T>C and G185C in patients were 0.106 and 0.004, respectively, and were nearly the same in controls. Total cholesterol and LDL-cholesterol levels were significantly higher for stroke patients having at least one 19W allele compared to non-carriers. A significant difference was also found for LDL-cholesterol levels of stroke patients; higher in ?1131C allele carriers compared to wild type patients. There was a trend for higher frequency of ischemic stroke among ?1131C allele carrier hypertensive, diabetic or obese subjects compared to non-carriers. However, APOA5 genotypes were not associated with the risk of ischemic stroke by logistic regression analysis. The present study demonstrated that carrying rare alleles of APOA5 S19W, ?1131T>C and G185C alone do not constitute a risk for ischemic stroke in the studied Turkish subjects.     

Angiotensin-converting enzyme insertion/deletion (rs106180) and angiotensin type 1 receptor A1166C (rs106165) genotypes and psoriasis: Correlation with cellular immunity,lipid profile,and oxidative stress markers

Psoriasis is a chronic inflammatory skin condition and angiotensin-converting enzyme (ACE) is a key circulating enzyme converting angiotensin (Ang) I to the vasoactive peptide Ang II. The exact role of ACE insertion (I)/deletion (D) polymorphism (rs106180) in psoriasis is not clear. We aimed to examine whether the ACE I/D and Ang II type 1 receptor (AT1R) A₁₁₆₆C-polymorphisms (rs106165), lipid profile, and stress oxidative are associated with susceptibility to psoriasis. One hundred patients with psoriasis and 100 sex- and age-matched unrelated healthy controls were recruited for this case-control study. ACE I/D and AT1R A₁₁₆₆C polymorphisms were identified by the polymerase chain reaction (PCR) and PCR-restriction fragment length polymorphism, respectively, malondialdehyde (MDA) was detected by the high-performance liquid chromatography, serum arylesterase (ARE) activity of paraoxonase and catalase activities were detected by the spectrophotometry, superoxide dismutase (SOD) activity and vascular adhesion protein (VAP)-1 were measured by ELISA. The presence of C allele of AT1R A₁₁₆₆C and I allele of ACE considerably increased the risk of psoriasis by 6.42-fold (P < 0.001). The distribution of II-genotype of ACE was significantly higher in psoriasis patients than in control group and increased the risk of disease by 3.11-times (P = 0.023). The higher levels of MDA in patients and the higher activity of SOD, ARE, and CAT was observed in healthy controls with I/D+I/I-genotype of ACE I/D. This study for the first time demonstrated that the ACE I/D and AT1R A ₁₁₆₆C genes polymorphisms robustly increases the risk of developing psoriasis in population from west of Iran. In addition, these individuals had significantly higher VAP-1 and MDA concentration and lower enzymatic and nonenzymatic antioxidant-status, suggesting that psoriatic patients carrying C allele of AT1R₁₁₆₆ polymorphism may be more susceptible to cardiovascular disease and myocardial infarction compared with A allele.     

Interleukin-1B (-511) gene polymorphism is associated with acute coronary syndrome in the Turkish population

Objectives: acute coronary syndrome (ACS) is defined as an inflammatory disease associated with development of atherosclerosis and instability. IL-1 is a candidate inflammatory cytokine that is thought to trigger ACS. The purpose of this study was to determine the relationship between IL-1 gene family polymorphisms (IL-1RN, IL-1B in positions -511 and +3953) and ACS in the Turkish population. Methods: a total of 381 people participated in the study, with 117 control subjects and 264 ACS patients. Of the 264 ACS patients, 112 were diagnosed with stable angina pectoris (SAP) and 152 were diagnosed with unstable angina pectoris (USAP). The polymerase chain reaction (PCR) was used to determine the genotype of IL-1RN. The genotypes of IL-1B (-511 and +3953) were determined by PCR, followed by restriction enzyme digestion of the PCR products. Results: there were no significant differences in both IL-1RN, IL-1B (-511 and +3953) genotype distributions and IL-1RN allele frequencies between ACS patients and the control subjects. In addition, no association was observed in the allele frequency of IL-1B (-511 and +3953) between ACS patients and controls (p = 0.113 and p = 0.859, respectively), or between SAP patients and controls (p = 0.575 and p = 0.359, respectively). However, IL-1B allele 1 (C) (-511) polymorphism in USAP patients was found to be significantly different from that of control subjects (p = 0.041, OR: 2.01; 95% CI: 1.985-3.933). A significant difference was also observed between USAP and SAP patients for IL-1B (+3953) allele 1 (C) polymorphism; (p = 0.043, OR: 1.522; 95% CI: 1.012-2.88). Conclusion: these results show that IL-1RN gene polymorphism has no association with ACS. However, the allele 1 (C) of IL-1B (-511) may be a risk factor for susceptibility to USAP in the Turkish population.     

Angiotensin II type 1 receptor gene polymorphism and telomere shortening in essential hypertension

Several genetic studies were carried out among hypertensive patients to assess allelic association at the 1166 position of the 3' untranslated region of angiotensin II type 1 receptor gene. In addition, attempts have also been made to find out whether telomere length attrition is associated with hypertension. The main aim of this study was to examine the association of A1166C polymorphism of angiotensin II type 1 receptor and telomere length with essential hypertension in Egyptian people. Angiotensin II type 1 genotyping and relative telomere length were investigated by PCR in 40 patients of essential hypertension and 15 healthy controls. The homozygous AA1166 allele frequency was 92.8% among the studied subjects. There was no intergroup variation in A allele frequency in normotensive group. The frequency of homozygous A allele was significantly higher in hypertensive than normotensive subjects (97.5 and 80%, respectively) with higher frequencies in male patients. The average telomere length ratio was significantly shorter in hypertensive than in normal subjects (1.08?±?0.3 and 1.54?±?0.18, respectively). No correlation was observed between telomere length ratio and body mass index. This study suggests that the homozygous A1166 allele of angiotensin II type 1 and short telomeres may be predisposing factors for essential hypertension in Egyptians and may be involved in the pathogenesis of the disease. Further strategies for treating high-risk patients could result in prevention or delay of end organ damage.     

Angiotensin II type 1 receptor A1166C gene polymorphism and essential hypertension in Calabar and Uyo cities,Nigeria

OBJECTIVES:

The angiotensin II protein is a vasoconstrictor that exerts most of its influence through the angiotensin II type 1 receptor (AT₁R). Inconsistent association between the A1166C polymorphism of the AT₁R gene and hypertension has been reported among various populations but not among the peoples of Calabar and Uyo. This study was designed to determine the frequency of the A1166C polymorphism of the AT₁R gene and its association with hypertension in a sample population of Calabar and Uyo.

MATERIALS AND METHODS:

A population-based case control design consisting of total of 1224 participants, 612 each of patients and controls were randomly recruited from hypertension clinics and the general population. Genotyping of the A1166C allele of the AT₁R gene to identify variants was performed using polymerase chain reaction and restriction enzyme digestion. Multiple regressions were applied to test whether the A1166 genotypes were predictors of hypertension.

RESULTS:

99% of the study population had the wild type AA genotype, and 1% was AC heterozygous carriers of the A1166C polymorphism.

CONCLUSION:

The A1166C polymorphism was not a predictor of hypertension in the sample population of Calabar and Uyo.     

AT2R − 1332 G:A polymorphism and its interaction with AT1R 1166 A:C,ACE I/D and MMP-9 − 1562 C:T polymorphisms: Risk factors for susceptibility to preeclampsia

The possible association of angiotensin type 2 receptor (AT2R) − 1332 G:A polymorphism with susceptibility to preeclampsia was studied in 252 women consisted of 155 women with preeclampsia and 97 healthy pregnant women. Also, the interaction of this polymorphism with angiotensin type 1 receptor (AT1R) 1166 A:C, angiotensin converting enzyme insertion/deletion (ACE I/D) and also with matrix metalloproteinase-9 (MMP-9) − 1562 C:T polymorphism was investigated. The AT2R − 1332 G:A polymorphism was detected using PCR–RFLP method. Significantly higher frequencies of GG+GA genotype and G allele of AT2R were observed in mild (80.2%, p = 0.003 and 47.5%, p = 0.012, respectively) and severe (77.8%, p = 0.034 and 48.1%, p = 0.026, respectively) preeclampsia compared to controls (60.8% and 35.1%, respectively). The presence of G allele was associated with 1.69-fold increased risk of preeclampsia (p = 0.005). In severe preeclamptic women, systolic and diastolic blood pressures in the presence of GG+GA genotype were significantly higher compared to those in the presence of AA genotype. The concomitant presence of both alleles of AT2R G and AT1R C was associated with 1.3 times increased risk of mild preeclampsia (p = 0.03). There was an interaction between AT2R G and ACE D alleles that significantly increased the risk of mild and severe preeclampsia by 1.38- and 1.3-fold, respectively. Also, interaction between MMP-9 T and AT2R G alleles increased the risk of severe preeclampsia 1.39-fold (p = 0.028). Our study demonstrated that the G allele of AT2R − 1332 G:A polymorphism is associated with an increased risk of preeclampsia. Also, epistatic interaction of G allele and each allele of the AT1R C, ACE D and MMP-9 T was associated with the risk of preeclampsia. Our findings suggest that the renin–angiotensin system (RAS) variants and gene–gene interactions affect the risk of preeclampsia.     

ACE and AGTR1 genes polymorphisms in left ventricular hypertrophy pathogenesis in humans

The role of A2350G polymorphism in exon 17 of the ACE gene and A1166C - in 3'-UTR of the AGTR1 in the pathogenesis of left ventricular hypertrophy was studied in patients with essential hypertension (EH) and arterial hypertension combined with diabetes mellitus type 2 (AH + DM2). Patients with EH and AH + DM2 did not differ from the control sample of healthy individuals by allele or genotype frequencies. However, an association of both polymorphisms with LVH was detected in EH patients. The frequency of 1166C allele was higher in patients with LVH (33.6% vs 20.7% without LVH). A1166C polymorphism determined the magnitude of left ventricular mass index (LVMI) in EH patients as well (p = 0.007). 2350G allele frequency of the ACE gene was in 1.5, and GG genotype--in 3.5-fold higher in EH patients with LVH, as compared without LVH. LVMI was significantly higher in patients with GG genotype as compared with heterozygotes and AA homozygotes (p = 0.002). Thus the presence of 1166C allele of AGTR1 and 2350G allele of ACE can be considered as predisposing factors for LVH development in EH. In contrast, association of studied polymorphisms with presence or LVH degree was not detected in patients with arterial hypertension combined with DM2. This may indicate another structure of genetic component of predisposition to LVH in different causes.     

Polymorphic markers of endothelial NO-synthase and angiotensin II vascular receptor genes and predisposition to ischemic heart disease

Allele and genotype frequency distribution patterns of the polymorphic regions at the genes for human endothelial NO-synthase (NOS3) (the ecNOS4a/4b VNTR and the Glu298Asp substitution) and the angiotensin II type 1 receptor (AT1)(the A1166C substitution) were compared in 83 unrelated healthy individuals and 88 patients with ischemic heart disease (IHD). In the group of patients statistically significantly higher frequencies of the NOS3 allele 4a (45.5 versus 19.3%), as well as the 4a/4a (15.9 versus 2.4%) and 4a/4b (59.1 versus 33.7%) genotypes were observed. Frequencies of the allele 4b (54.5% versus 80.7%) and the 4b/4b homozygotes (25.0 versus 63.9%) were statistically significantly lower in the group of IHD patients than in healthy individuals. The IHD patients were statistically significantly different from the healthy subjects also in the distributions of the AT1 genotypes. In the former group, a significantly decreased frequency of the AA homozygotes (51.1 versus 65.1%) and an increased frequency of AC heterozygotes (40.9 versus 27.7%) were observed. Thus, in the Moscow population the ecNOS4a/4b VNTR of the NOS3 gene and the A1166C polymorphism of the AT1 gene are associated with the IHD development. Furthermore, the correlation with the IHD revealed was much stronger for the NOS3 VNTR locus.     

E-cadherin gene 3′-UTR C/T polymorphism in Turkish patients with nephrolithiasis

Nephrolithiasis is a complex disease and many gene polymorphisms have been associated with stone formation. In this study we aimed to investigate another possible relationship between E-cadherin gene (CHD1) 3′-UTR C/T polymorphism and calcium oxalate nephrolithiasis in the Turkish population. Study population was composed of 143 patients with nephrolithiasis and 158 control subjects. CHD1 3′-UTR C/T polymorphism was analysed using polymerase chain reaction (PCR)-restriction fragment length polymorphism (RFLP) technique. Genotype distribution of the investigated polymorphism was not deviated from Hardy–Weinberg equilibrium (HWE) in patients and control subjects (P > 0.05). C allele frequency was 85.7 and 85.1% in patients and controls, respectively (P = 0.836). Genotype distributions of the CHD1 3′-UTR C/T polymorphism among patients were also not significantly different from those among control subjects (P = 0.636). Our results showed that there is no association between the CHD1 gene 3′-UTR C/T polymorphism and nephrolithiasis in our population.     

Association of angiotensin converting enzyme (ACE) gene I/D polymorphism and polycystic ovary syndrome (PCOS)

This study was conducted in Turkish patients with polycystic ovary syndrome to determine the frequency of I/D polymorphism genotypes of angiotensin converting enzyme gene, and to examine the role of this polymorphism in polycystic ovary syndrome development. Genomic DNA obtained from 200 persons (100 patients with polycystic ovary syndrome and 100 healthy controls) was used in the study. DNA was multiplied by polymerase chain reaction using I and D allele-specific primers. Polymerase chain reaction products were assessed with a charge coupled device (CCD) camera by being exposed to 2% agarose gel electrophoresis. There was statistically significant difference between the groups with respect to genotype distribution (p < 0.001). The D allele frequency was indicated as 68% and I allele was as 32% in the patients, whereas it was 51.5-48.5% respectively in the control group. As a result of our study we may assert that angiotensin converting enzyme gene I/D polymorphism DD genotype should be considered as a genetic marker in polycystic ovary syndrome development in this Turkish study population.     

The Risk of Coronary Artery Disease Associated with Cigarette Smoking and Hypercholesterolemia Is Additionally Increased by the Presence of the AT 1 R Gene 1166C Allele

Cigarette smoking and hypercholesterolemia influence the renin-angiotensin system (RAS) functions, including increased RAS-mediated vasoconstriction, mitogenic signaling, and angiotensin II type 1 receptor (AT1R) expression. We have explored the interactions of the AT1R gene 1166 A>C polymorphism and traditional risk factors using an epidemiological approach. The study cohort included 341 subjects; 172 were patients with angiographically confirmed coronary artery disease (CAD) and 169 were blood donors. The 1166 A>C polymorphism was genotyped using the PCR-RFLP method. We found a synergy of the 1166C allele with cigarette smoking (synergy indices: SI = 1.41, SIM = 1.33), LDL cholesterol levels > or = 3 mmol/l (SI = 1.25, SIM = 1.19), and elevated total cholesterol (> or =5 mmol/l) levels (SI = 1.15, SIM = 1.13). In each case, the estimated CAD risk was greater than that predicted by assuming the additivity and multiplication of effects. We conclude that the 1166C allele increases the risk of CAD associated with the presence of cigarette smoking and hypercholesterolemia.     

No association of PTPN22 R620 W gene polymorphism with rheumatic heart disease and systemic lupus erythematosus

Rheumatic heart disease (RHD) or acute rheumatic fever (ARF) develops as a consequence of an exaggerated immune response to Group A beta haemolytic streptococci causing pharyngitis. The molecular mimicry appears between human cardiac myosin and M protein of group A streptococcal membranes. The polymorphism of the protein tyrosine phosphatase nonreceptor 22 (PTPN22) gene, which encodes an important negative regulator of T cell activation, has been reported to be associated with susceptibility to several autoimmune diseases such as SLE and RA. The objective of this study was to investigate whether PTPN22 R620W polymorphism confers susceptibility to RHD in Turkish population. PTPN 22 R620W (rs2476601, A/G) polymorphism was genotyped by PCR-RFLP in 121 patients with RHD who fulfilling the revised classification criteria of Jones, and 160 healthy control (HC), and also 137 SLE as a diseased–control. The frequency of GG and AG genotypes were found to be 94% (114), 6% (7) in RHD, respectively and 96% (153) and 4% (7) in HC, respectively. The homozygous AA genotype was not present in RHD and HC. There was no statistically significant difference between RHD and HC according to the frequency of AG heterozygote genotype (P = 0.831; OR = 1.13; 95% CI 0.37–3.46). The frequency of the rare allele A was also very similar in RHD patients and HC (3, 2% respectively). A similar result was also found between SLE and HC. Our results demonstrated that the PTPN22 R620W polymorphism is not associated with RHD nor with SLE in Turkish population.     

Investigation of C5a receptor gene 450 C/T polymorphism in Turkish patients with familial Mediterranean fever

Familial Mediterranean fever (FMF) is a genetic disorder with acute inflammatory serosal attacks due to MEFV gene mutations which resides in chromosome 16. Lack of a C5a inhibitor activity in the peritoneum has previously been proposed in part to contribute in propagation of the serosal inflammation in FMF attacks. The aim of this study is to investigate C5a receptor (C5aR) gene polymorphism in patients with FMF and its relation to the main features of the disease. A polymorphism in the coding region of C5aR gene leading to C to T transition at nucleotide position 450 has been investigated in 85 non-related Turkish FMF patients and 160 non-related healthy controls by using PCR-RFLP. The frequencies of C5aR gene 450 CT genotype and T allele were not significantly different between Turkish FMF patients and healthy subjects (14.12 and 8.24% for FMF vs. 10 and 5% for controls, respectively). C5aR gene 450 CT genotype tended to associate with the presence Henoch-Schonlein purpura (OR: 1.25, 95% CI: 0.917–1.704, P = 0.017) but with no other clinical findings of the disease. C5aR polymorphism might be searched in populations having high prevalence of FMF.     

DD genotype of ace gene I/D polymorphism is associated in a turkish study population with osteoarthritis

This study was conducted in Turkish osteoarthritis patients to determine the frequency of I/D polymorphism genotypes of angiotensin converting enzyme gene, and to examine the role of this polymorphism in osteoarthritis development. Genomic DNA obtained from 200 persons (135 patients with osteoarthritis and 65 healthy controls) was used in the study. DNA was multiplied by polymerase chain reaction using I and D allele-specific primers. Polymerase chain reaction products were assessed with CCD camera by being exposed to 2% agarose gel electrophoresis. There was statistically significant difference between the groups with respect to genotype distribution (P < 0.001). The D allele frequency was indicated as 69% and I allele was as 31% in the patients, whereas it was 55–45% in the control group. Consequently, in this study, we may assert that ACE gene I/D polymorphism DD genotype determination is significant criteria for identifying patients who are likely to develop osteoarthritis in east population of Turkey.     

Glu298Asp polymorphism of the endothelial nitric oxide synthase gene in Turkish patients with ischemic stroke

The low plasma nitric oxide concentrations and reduced vascular reactivity are considered major proatherogenic mechanisms in cardiovascular diseases. The present study aimed to assess the allelic frequency and the genotypic distribution of the Glu298Asp gene polymorphism at exon 7 of endothelial nitric oxide synthase (eNOS) gene in Turkish ischemic stroke patients compared to appropriate healthy controls, and to correlate the genetic findings with stroke subtypes. The study population included 146 (75 males, 71 females) patients with ischemic stroke which were categorized according to the Trial of ORG 10172 in Acute Stroke Treatment (TOAST) and 133 (34 males, 99 females) healthy subjects. The eNOS polymorphism was identified with a PCR followed by RFLP with the restriction enzyme BanII. Genotypes were defined as GG, GT, and TT according to the presence of the G and T alleles. In this case-control study, we did not find any significant difference in either the genotypic distribution or allelic frequency of Glu298Asp gene polymorphism between the patients and the controls. In addition, there was also no significant difference for the genotype distribution and the allelic frequency among the stroke subtypes. The results suggested the lack of the association between the Glu298Asp gene polymorphism and ischemic stroke or subtypes of ischemic stroke in the Turkish population.     

Association analysis of the E-selectin 98G > T polymorphism and the risk of childhood ischemic stroke

Genes related to platelet and arterial endothelial function have been recently considered as independent risk factors for stroke. We aimed to analyze a relationship between the E‐selectin 98G > T polymorphism and stroke in children and to observe the transmission of E‐selectin alleles from heterozygous parents to their affected children. We studied 59 children after stroke, 112 parents, and 87 healthy children. The E‐selectin 98G > T polymorphism was analyzed with the polymerase chain reaction‐restriction fragment length polymorphism (PCR‐RFLP) method. The frequency of the 98T allele in patients was almost twofold lower than in controls (5.1% vs. 9.8%, p = 0.145, odds ratios (OR) = 0.49) as well as carriers of the 98T allele (19.5% in controls vs. 8.5% in cases, p = 0.067, OR = 0.38). The G allele of the E‐selectin 98G > T polymorphism was more frequently transmitted to the children after stroke compared to the T allele (68% vs. 32%). In conclusion, we did not confirm the relationship between the 98G > T polymorphism of the E‐selectin gene and childhood ischemic stroke. There is still a need for further studies. Copyright © 2010 John Wiley & Sons, Ltd.     

Association of serotonin 2A receptor and lack of association of CYP1A2 gene polymorphism with tardive dyskinesia in a Turkish population

The aim of this study was to investigate the possible association of serotonin 2A receptor gene (HTR2A) -1438 G/A polymorphism and CYP1A2 gene 163C/A polymorphism with tardive dyskinesia (TD) in a Turkish population. A total of 47 patients with persistent TD, 80 patients who were consistently without TD, and 100 healthy controls were included in this study. The polymorphic regions of -1438 G/A polymorphism of HTR2A receptor gene (rs6311) and 163C/A of CYP1A2 (rs762551) gene were amplified using polymerase chain reaction (PCR), followed by digestion with restriction enzymes MspI and Bsp1201. Genotype and allele frequencies were calculated by the chi(2)-test. Crude and adjusted odds ratios (ORs) were estimated, and 95% confidence intervals (CIs) were computed by multivariate logistic regression analysis. The genotype and allele frequencies of HTR2A and CYP1A2 gene were similar in schizophrenia with TD, schizophrenia without TD, and healthy controls. The logistic regression analysis showed that cumulative exposure to antipsychotic drugs for every year (p = 0.003; OR = 1.15; CI = 1.07-1.23), and AA genotype of HTR2A gene (p = 0.0258; OR = 4.34; CI = 1.19-15.81) are risk factors for TD. The same logistic regression model showed no association between CYP1A2 polymorphism and TD. The results of the present study seem to indicate that HTR2A gene polymorphism influences the tendency to express TD following prolonged antipsychotic drug exposure in Turkish schizophrenia patients.     

Association of Angiotensin II Type 1 Receptor (A1166C) Gene Polymorphism and Its Increased Expression in Essential Hypertension: A Case-Control Study

Objectives

Hypertension is one of the major cardiovascular diseases. It affects nearly 1.56 billion people worldwide. The present study is about a particular genetic polymorphism (A1166C), gene expression and protein expression of the angiotensin II type I receptor (AT1R) (SNP ID: rs5186) and its association with essential hypertension in a Northern Indian population.

Methods

We analyzed the A1166C polymorphism and expression of AT1R gene in 250 patients with essential hypertension and 250 normal healthy controls.

Results

A significant association was found in the AT1R genotypes (AC+CC) with essential hypertension (χ² = 22.48, p = 0.0001). Individuals with CC genotypes were at 2.4 times higher odds (p = 0.0001) to develop essential hypertension than individuals with AC and AA genotypes. The statistically significant intergenotypic variation in the systolic blood pressure was found higher in the patients with CC (169.4±36.3 mmHg) as compared to that of AA (143.5±28.1 mmHg) and AC (153.9±30.5 mmHg) genotypes (p = 0.0001). We found a significant difference in the average delta-CT value (p = 0.0001) wherein an upregulated gene expression (approximately 16 fold) was observed in case of patients as compared to controls. Furthermore, higher expression of AT1R gene was observed in patients with CC genotype than with AC and AA genotypes. A significant difference (p = 0.0001) in the protein expression of angiotensin II Type 1 receptor was also observed in the plasma of patients (1.49±0.27) as compared to controls (0.80±0.24).

Conclusion

Our findings suggest that C allele of A1166C polymorphism in the angiotensin II type 1 receptor gene is associated with essential hypertension and its upregulation could play an important role in essential hypertension.