Angiotensin Converting Enzyme Gene Gene Research Articles

Angiotensin-converting enzyme gene (ACE) polymorphisms are associated with dysregulation of biochemical parameters in hypertensive patients.

The genetic component, including genes and their variants, plays a significant role in the pathophysiology of arterial hypertension (AH). Thus, clinical, epidemiological and genetic studies have been carried out to improve the understanding of disease mechanisms, improve diagnostic quality and contribute to prevention. To determine the association of risk factors, biochemical parameters and different ACE gene polymorphisms with AH. The case-control study was carried out in the population of Ouro Preto, Brazil. The subjects answered a questionnaire containing clinical and sociodemographic data. The ACE gene polymorphisms rs4291, rs4363 and rs4335 were evaluated by real time-polymerase chain reaction (real-time PCR) in 310 people (155 hypertensive and 155 normotensive patients), in addition to biochemical parameters. A multivariate logistic regression model was used to identify factors associated with AH. Analysis of continuous variables was performed using the Kruskal-Wallis test to assess significance between groups and Dunn's post-test for multiple comparisons. The results showed that AH was associated with age, education, smoking, obesity and high levels of triglycerides, sodium, glucose and uric acid. Regarding the biochemical parameters, in hypertensive patients, the rs4363 and rs4335 polymorphisms were associated with high levels of triglycerides, urea and glucose; the rs4291 polymorphism was associated with elevated urea and glucose levels. No association was detected between SNPs and HA. AH was associated with socioeconomic status, lifestyle habits and biochemical parameters. ACE polymorphisms may have influenced the levels of triglycerides, urea and glucose in hypertensive patients.

Association of Angiotensin-Converting Enzyme gene polymorphism in Pakistani women with the atypical steroidogenesis in Polycystic ovarian syndrome: A case-control study.

BackgroundPolymorphism in the angiotensin-converting enzyme gene (ACE) is responsible for elevated ACE concentrations in plasma. High ACE levels induce insulin resistance and hyperandrogenism, which are the main attributes of polycystic ovary syndrome (PCOS). Therefore, it was hypothesized that I/D polymorphism plays a role in the pathogenesis of PCOS.ObjectiveA case-control study was designed to investigate the association of I/D polymorphism of the ACE gene with PCOS in Pakistani women of reproductive age.MethodsACE I/D polymorphism was assessed in 252 women of age group 16–40 years. For genotypic analysis, PCR amplification of genomic DNA was carried out. Statistical analysis was performed to interpret the results using SPSS software.ResultsOur study showed that PCOS women were more likely to have a high body mass index and waist circumferences. Most PCOS patients had menstrual irregularities 99.3%, hirsutism 75.2% and cysts in ovaries 66.6%, along with other hyperandrogenic conditions (P-value = 0.001). The genotypic and allelic frequencies were significantly different between patients and controls. There was a significant association of three genotypes with the ratio of LH: FSH among PCOS patients (P = 0.05). Anthropometric characters, comorbidities, clinical symptoms, and PCOS conditions showed no statistical significance with ACE polymorphism.ConclusionsACE I/D polymorphism was not found associated with clinical conditions of PCOS in women of reproductive age. However, it was associated with atypical steroidogenesis. So, it indicates that ACE I/D polymorphism aggravates the pathogenesis of PCOS.

Association of ACE gene polymorphism with cardiovascular determinants of trained and untrained Iranian men

BackgroundThe insertion (I) rather than deletion (D) of human angiotensin converting enzyme gene (ACE) is associated with lower circulating ACE activity and with endurance performance among Caucasians. The frequency of the ACE gene I/D allele in Iranian sample seems to be more similar to the Caucasians. To assess the possible relationship between I/D polymorphism of ACE gene with athletic status and selected cardiovascular indices and VO2max in an Iranian population, DNA samples were obtained from 57 trained and untrained men, with soccer as their main training modality. Genotyping for ACE I/D polymorphism was performed using polymerase chain reaction. VO2max was determined by an incremental test to volitional exhaustion on a motorized treadmill.ResultsI/D genotype was neither associated with elite athlete status nor with VO2max, resting heart rate, systolic and diastolic blood pressure. There was no interaction effect of training statue x ACE genotype for each of the examined indices.ConclusionsACE gene variation was not a determinant of cardiovascular function and VO2max in either trained or untrained Iranian participating in soccer. The absence of an association between either I/D genotype and elite Iranian athlete status and better cardiovascular function also suggests that the ACE gene does not contribute significantly to the phenomenal success of Iranian soccer players.

Association of 1166A>C AT1R, -1562C>T MMP-9, ACE I/D, and CCR5Δ32 Polymorphisms with Abdominal Aortic Aneurysm in Croatian Patients

The purpose of this case-control study was to assess the association of abdominal aortic aneurysm (AAA) in Croatian patients with four genetic polymorphisms: SNP 1166A>C in the angiotensin II type 1 receptor gene (AT1R); SNP -1562C>T in the matrix metalloproteinase-9 gene (MMP-9); the deletion of 32 bp in the chemokine receptor 5 gene (CCR5); and the insertion/deletion (I/D) of 287 bp in the angiotensin-converting enzyme gene (ACE). Case-control study conducted with 117 patients with confirmed AAA (AAA+) and 117 control subjects (AAA-). Genotyping was performed using PCR or PCR-RFLP analysis. Statistical analyses were performed using MedCalc 12.1 software. The deletion of 287 bp in the ACE gene (allele D) was more frequently found among AAA+ patients than AAA- subjects (66.7% vs. 47.9%, p = 0.0001), due principally to a higher percentage of DD homozygotes (46.2% vs. 15.4%, p < 0.0001). The associated increased risk for AAA was detected in both the nonadjusted recessive model of inheritance (odds ratio [OR] = 3.00, 95% confidence interval [CI] = 1.88-4.79, p = < 0.0001) and when adjusted for age, sex, smoking, hypertension, and hyperlipidemia (OR = 4.96; 95% CI = 1.68-14.59, p = 0.004). The adjusted recessive models also showed increased risk for AAA for the carriers of MMP-9 T allele (OR = 15.69, 95% CI = 1.40-175.41, p = 0.025). Patients with small aneurysms compared with those with large ones were more frequent carriers of the AT1R allele C (37.8% vs. 23.2%, p = 0.029), and logistic regression analysis showed decreased risk for developing large aneurysms in both adjusted models, dominant and recessive (OR = 0.3929, 95% CI = 0.1554-0.9932, p = 0.0483 and OR = 0.1728, 95% CI = 0.0331-0.9023; p = 0.0374, respectively). No difference among any type of the studied groups or subgroups was observed regarding the CCR5Δ32 polymorphism. ACE I/D is associated with AAA, and 1166A>C AT1R with the size of the aneurysm, while -1562C>T MMP-9 and CCR5Δ32 polymorphisms are most probably not associated with AAA in Croatian patients.

Angiotensin-converting enzyme gene insertion-deletion polymorphism is a risk marker for Alzheimer's disease in a Chinese population: a meta-analysis of case-control studies.

It has long been known that the polymorphisms of angiotensin-converting enzyme gene (ACE) are associated to increase risk of Alzheimer's disease (AD) in Chinese population. However, consistent results were not obtained among studies. This study is aimed to clarify the association between ACE insertion (I)/deletion (D) polymorphism (rs1799752) and AD. Literatures were searched from PubMed, Embase, Cochrane Library, CNKI, Wanfang and VIP databases without language restrictions. Eleven separate studies were suitable for the inclusion criterion. The selected studies contained 2,763 Chinese participants, including 1,383 in AD group and 1,380 controls. Pooled odds ratios (ORs) were calculated to assess the association between ACE I/D polymorphism and AD. Our case-control data indicated that ACE insertion is a risk allele in all genetic models: additive model (I vs. D: OR = 1.32, 95 % CI 1.07-1.62, P = 0.008), dominant model (II + ID vs. DD: OR = 1.61, 95 % CI 1.08-2.41, P = 0.02) and recessive model (II vs. ID + DD: OR = 1.39, 95 % CI 1.07-1.81, P = 0.01). Heterogeneity between studies was significant (P < 0.10) but not in stratification defined by the selection of controls (P > 0.10). After stratification according to the selection of controls, the carrier of ACE I allele remained a high risk for AD in population-based samples subgroup (I vs. D: P = 0.008, OR = 1.32, 95 % CI 1.07-1.61, P(heterogeneity) = 0.47, I (2) = 0 %). Our study provided solid evidence suggesting that ACE gene I/D polymorphism is a genetic risk factor for AD in Chinese population.

Null genetic risk of ACE gene polymorphisms with nephropathy in type 1 diabetes among Egyptian population

Reported to date, strong evidence exists in multiple studies for genetic predisposing in the development of diabetic nephropathy, and no studies addressed this issue among Egyptian population. The results of angiotensin converting enzyme gene (ACE) in the susceptibility to nephropathy in type 1 diabetes with nephropathy are conflicting. We aim to identify the associations of two ACE gene polymorphisms ( PstI, A > G substitution and a 287-bp insertion/deletion) with nephropathy in type 1 diabetes in Egyptian children/adolescents. Our case-control study contained 140 diabetic individuals; 80 diabetic with nephropathy as cases, and 60 diabetic subjects without nephropathy as control group. Amplified DNA from peripheral leucocytes/buccal mucosa was genotyped for using polymerase chain reaction and enzymatic assay. We found no significant differences in the distribution of ACE insertion/deletion and PstI genotypes or allele frequencies were observed between the examined groups. Frequencies of PstI–indel haplotypes were similar in all of our study groups. In both cases and control subjects, ACE activity and microalbuminuria were highest among D/D homozygotes and lowest in I/I homozygotes, while a dissimilar result was seen in PstI polymorphism. Our findings in Egyptian population strongly conclude that there is no association between the ACE gene I/D and PstI polymorphisms with nephropathy in type 1 diabetes.

The Angiotensin Converting Enzyme Gene I/D Polymorphism in Polish Rowers

Angiotensin converting enzyme gene (ACE) is the most frequent investigated gene in the context of genetic conditioning of sports-predispositions. Product of this gene is a key-element in the renin-angiotensin system responsible for the regulation of blood pressure. In this study DNA polymorphism in the ACE gene was studied in Polish rowers in order to examine the hypothesis that ACE genotype is associated with athletes performance. Fifty-five male Polish rowers including Olympic and World champions were recruited for this study. Control samples were prepared from 115 unrelated volunteers. PCR amplification of the insertion (I) or deletion (D) fragment of ACE gene was performed. Genotype distribution and allele frequencies were determined by genotype and gene counting. Significance was assessed by chi2 analysis. ACE genotype distributions amongst subjects and controls were in Hardy-Weinberg equilibrium. Compared with controls, the frequency of I allele differ significantly from that found in rower's group: 56.3% vs. 44.3%, (P=0.038) and ACE genotype frequency amongst the whole athletes group (30.9% II, 50.9% ID, 18.2% DD) was also different from expected values (control group 19.1% II, 50.4% ID, 30.4% DD; P=0.039). This data confirm a positive association of the I allele of ACE gene with endurance performance.

Gene polymorphism of the renin-angiotensin system in six ethnogeographic regions of Belarus

The insertion/deletion polymorphism of the angiotensin-converting enzyme gene (ACE) and the T174M polymorphism of the angiotensinogen gene (AGT) have been studied in six ethnic/geographic regions of Belarus. Significant intrapopulation differences in ACE genotype frequencies have been found for the northern and eastern regions (the Dvina and Dnepr basins, respectively). Significant differences in the AGT genotype frequencies have been found between populations of the Dnepr basin and populations of all other Belarusian regions. The allele and genotype frequencies of the genes studied in the Belarusian population and populations of other regions of the world have been compared. The frequencies of the insertion (I) and deletion (D) alleles of the ACE gene in the Belarusian population are 50.7 and 49.3%, respectively, which is similar to these frequencies in European countries. The frequency of the M allele of the AGT gene in Belarus is 16.6%, which is higher than its frequency in populations of European, African, and Asian origins.

Angiotensin-converting enzyme insertion/deletion polymorphism is not associated with susceptibility and outcome in sepsis and acute respiratory distress syndrome

The insertion/deletion (I/D) of a 289 base pair Alu repeat sequence polymorphism in the angiotensin-converting enzyme gene (ACE) has been shown to predict susceptibility and outcome in the acute respiratory distress syndrome (ARDS). We hypothesized that the I/D polymorphism also confers susceptibility to sepsis and is a predisposing factor for morbidity and mortality of patients with severe sepsis. Case-control study including 212 consecutive patients fulfilling criteria for severe sepsis admitted to a Spanish network of postsurgical and critical care units, and 364 population-based controls. Susceptibility to severe sepsis was evaluated as primary outcome; mortality in severe sepsis, susceptibility to sepsis-induced ARDS, and mortality in sepsis-induced ARDS were examined as secondary outcomes. An additive model of inheritance in which patients were classified into three genotype groups (II, ID, and DD) was used for association testing. Genotype and allele frequencies of I/D were distributed similarly in all septic, ARDS, and non-ARDS patients and in population-based controls. ACE I/D polymorphism was not associated with severe sepsis susceptibility or mortality. The ACE I/D polymorphism was associated neither with sepsis-induced ARDS susceptibility (p=0.895) or mortality (p=0.950). These results remained nonsignificant when adjusted for other covariates using multiple logistic regression analysis or Kaplan-Meier estimates of 28-day survival. Our data do not support an association of the ACE gene I/D polymorphism with susceptibility or mortality in severe sepsis or with sepsis-induced ARDS in Spanish patients.

Angiotensin-Converting Enzyme Insertion/Deletion (ACE I/D) and Angiotensin II Type 1 Receptor (AT1R) Gene Polymorphism and Its Association with Preeclampsia in Chinese Women

Objective: To investigate whether polymorphisms of angiotensin converting enzyme gene (ACE) and angiotensin II receptor type 1 gene (AT1R) are associated with etiology of preeclampsia and renal impact in women with preeclampsia. Methods: DNA was extracted from peripheral blood of 133 patients with preeclampsia and 105 healthy pregnant women. The I/D polymorphism of the ACE gene was assessed by polymerase chain reaction, and the A1166C polymorphism of the AT1R gene was additionally assessed by DdeI digestion. The level of proteinuria, fasting serum urea, creatinine and uric acid were investigated according to different genotypes of ACE and AT1R genes. Results: The frequency of genotypes of the ACE gene and the AT1R gene was similar in preeclampsia and normal pregnancy. DD and ID genotype predominated in patients with severe proteinuria, as well as increased serum urea and uric acid. Serum creatinine was also increased, but no significant difference was found among three genotypes. The level of proteinuria, serum uric acid, urea, and creatinine did not vary between different AT1R genotypes. Compared with patients without renal dysfunction, the frequency of DD and ID genotypes of ACE gene was much higher in those with renal dysfunction, but AC and CC genotypes of AT1R gene were not. Conclusion: We found no association of the two gene polymorphisms with preeclampsia. However, ACE gene I/D polymorphisms were associated with the severe proteinuria and renal dysfunction seen in preeclampsia. Preeclampsia patients carrying the D allele may be susceptible to renal dysfunction.

Association of Angiotensin Converting Enzyme Gene Polymorphisms with Left Ventricular Hypertrophy

The angiotensin converting enzyme gene (ACE) is of much interest as a candidate gene conferring an individual's genetic susceptibility to left ventricular hypertrophy (LVH). LVH has long been thought to be an end point of essential hypertension (EH), rather than a separate entity, though it is influenced by a unique set of hormonal, vascular and genetic factors. In this study, we attempted to determine whether two representative polymorphisms of the ACE gene, ACE I/D and 2350 G>A, known to be associated with EH and to have a highly significant influence on plasma ACE levels, could implicate ACE as a quantitative trait locus (QTL) for LVH. We carried out a retrospective, case-control study of the two ACE polymorphisms amongst 180 nationals (50 LVH patients and 130 controls) from the United Arab Emirates (Emirati)--an ethnic group characterized by an absence of alcohol intake and cigarette smoking--for putative correlations with LVH. Clinical diagnoses of LVH were based on echocardiographic and ECG criteria. ACE I/D and 2350 G>A genotypes were determined by polymerase chain reaction (PCR) and restriction digestion. Univariate and multivariate logistic regression analyses revealed an association between ACE polymorphisms and LVH. Haplotype analysis further supported this finding. The ACE I/D and ACE 2350 G>A polymorphisms were in strong linkage disequilibrium and were independently associated with LVH, suggesting that ACE is likely to be a QTL for LVH. In conclusion, This is the first association study of the ACE 2350 G>A polymorphism with LVH; the results showed that this polymorphism, along with ACE I/D, is associated with LVH.

The Effects of the ACE Gene Insertion/Deletion Polymorphism on Glucose Tolerance and Insulin Secretion in Elderly People Are Modified by Birth Weight

The I allele of an insertion/deletion (I/D) polymorphism in the angiotensin-converting enzyme gene (ACE) appears to be protective against the complications of type 2 diabetes. Low birth weight, a marker of an adverse intrauterine environment, is associated with higher rates of type 2 diabetes. We examined whether the ACE I/D polymorphism could explain or modify the association between low birth weight and adulthood glucose tolerance. We measured plasma glucose and insulin concentrations after an oral glucose challenge in a group of 423 men and women, ages 65-75 yr, with measurements at birth recorded. The presence of the I allele was associated with shorter duration of gestation (P = 0.006) and, relative to gestational age, higher birth weight (P = 0.008) and length (P = 0.02). The I allele was associated with lower glucose at 120 min (P = 0.04) and a greater insulin response (P = 0.03 for insulin at 30 min and P = 0.06 for insulin area under the curve) to a standard oral glucose tolerance test. However, the associations between the ACE genotype and adulthood insulin secretion were only present in people with low birth weight (P for interaction birth weight * ACE genotype on insulin at 30 min = 0.003 and on insulin area under the curve = 0.05). The ACE I allele is associated with shorter duration of gestation and higher birth weight. The association between the presence of the ACE I allele and increased indices of adult insulin secretion is confined to subjects with low birth weight. We suggest that these findings reflect interactions between genotype and intrauterine environment with resulting changes in gene expression.

Genetic Predisposition to Neurological Symptoms in Lacunar Infarction

Objective: Lacunar infarction is a unique stroke entity with characteristic symptoms. However, it is often silent clinically. The possible genetic predisposition to symptoms of lacunar infarction was investigated. Methods: One-hundred and fifty-one patients with lacunar stroke were consecutively recruited. Lacunar stroke was diagnosed based on both neurological symptoms and lacunar lesion(s), demonstrated by MRI, that were responsible for the symptoms. One-hundred and fifty control subjects with MRI-proven lacunar lesions without neurological symptoms served as controls. There was no significant difference in age, sex and prevalence of known risk factors between cases and controls. Insertion and deletion polymorphisms of the angiotensin-converting enzyme gene (ACE), M235T substitution of the angiotensinogen gene (AGT), and A1133C substitution of type 1 receptor of the angiotensin II gene were determined. Results: The frequency of ACE D allele was significantly higher in symptomatic patients compared with asymptomatic subjects (0.44 vs. 0.36, p < 0.05). The genotype distribution of AGT was significantly different between symptomatic and asymptomatic patients (χ² = 6.6, p = 0.037). Multiple logistic regression analysis revealed that ACE gene and AGT genotypes were independently associated with the neurological manifestation of lacunar infarction. In subjects with 1 lacuna, the odds ratio of the ACE DD genotype for symptomatic manifestation was 4.98 (95% CI 1.25–19.9). In subjects with 4 or more lacunae, the odds ratio of the ACE II genotype for symptomatic manifestation was 0.24 (95% CI 0.10–0.56). Furthermore, the ACE gene polymorphism was significantly different between symptomatic patients with a single lacuna and asymptomatic subjects with 4 or more multiple lacunar infarctions (χ² = 10.6, p = 0.005). Conclusion: These findings suggest that 2 subtypes of lacunar infarction, single symptomatic lacuna and multiple asymptomatic lacunae, may possess different genetic backgrounds. Subjects with the ACE DD genotype could be more predisposed to be symptomatic in first-ever lacunar stroke, while the ACE II genotype may convey resistance to symptoms even after multiple lacunar strokes. Polymorphism of genes of the renin-angiotensin system could be involved in the manifestation of neurological symptoms of lacunar infarction.

Angiotensin-converting enzyme insertion/deletion polymorphism modulates coronary release of tissue plasminogen activator in response to bradykinin.

The aim of this study was to assess the relationship between the angiotensin converting enzyme gene (ACE) genotype and endothelium-dependent coronary vasomotor and fibrinolytic activity. The ACE DD genotype has been reported to be a risk factor for myocardial infarction. However, the mechanism is unknown. The fibrinolytic and renin-angiotensin systems are linked via ACE at the vascular beds. We studied 73 patients (II: n=24; ID: n=37; DD: n=12) who underwent diagnostic cardiac catheterization. Graded doses of bradykinin (BK) (0.2, 0.6, 2.0 microg/min) and acetylcholine (30,100 microg/min) were administered into the left coronary artery. Coronary blood flow (CBF) was evaluated by measuring Doppler flow velocity. Blood samples were taken from the aorta (Ao) and the coronary sinus (CS). Coronary release of tPA antigen was determined as a CS-Ao gradientXCBFX[(100-hematocrit) / 100]. ACE genotypes were determined using polymerase chain reaction. The ACE genotype did not appear to affect coronary macro- and microvascular responses induced by BK or acetylcholine. Coronary tissue plasminogen activator (tPA) release induced by BK was depressed in subjects with the ACE DD genotype. ACE levels in the DD genotype were significantly higher than those in the ID or II genotype. In all of the subjects, there was a significant negative correlation between the serum level of ACE activity and net coronary tPA release in response to BK at 0.6 microg/min. In conclusions, the DD genotype of the ACE gene impairs the coronary release of tPA induced by BK.

Genes and diabetic nephropathy: what have we learnt so far?

Genes and diabetic nephropathy: what have we learnt so far?

Angiotensin-converting enzyme gene insertion/deletion (I/D) polymorphism in hypertensive patients with different degrees of obstructive sleep apnea.

To investigate the role of the angiotensin-converting enzyme gene (ACE) insertion (I)/deletion (D) polymorphism in hypertensive patients with different degrees of obstructive sleep apnea (OSA). A case-control study was performed. One hundred seventy four Chinese subjects were divided into four groups depending on the severity of OSA as follows: 1) normal control group (NC, n=68), 2) isolated hypertension group (HT, n=45), 3) hypertensive patients with mild OSA group (MO, n=27), and 4) hypertensive patients with moderate to severe OSA group (MSO, n=34). The distribution of ACE gene I/D allele and genotypes were analyzed in the subject population, as was an OSA pedigree. The study showed that the frequency of ACE gene I/D polymorphism differed significantly among the four groups. The frequency of I allele and II genotype were significantly higher in the MSO group than in the other groups (p<0.05). The distribution of I allele and II genotype showed no significant difference between any of the other groups (p>0.05, respectively). Meanwhile the higher frequency of I allele and II genotype was observed in the OSA pedigree. The higher frequency of ACE gene I allele and II genotype were closely associated with the hypertensive patients with MSO. The inherited factors played an important role in the pathogenesis of hypertensive patients with MSO.