Human Angiotensin-converting Enzyme Gene Research Articles

Polymorphisms in the human angiotensin converting enzyme gene (ACE) linked to susceptibility of COVID-19 and malaria infections in the Ghanaian population

Genetic variations in the human angiotensin converting enzyme gene (ACE) influence ACE enzyme expression levels in humans and subsequently influence both communicable and non-communicable disease outcomes. More recently, polymorphisms in this gene have been linked to susceptibility and outcomes of infectious diseases such as the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and malaria infections. This study is the first to investigate the genetic diversity of ACE and ACE2 polymorphisms in the Ghanaian population. Archived filter blood blot samples from malaria patients aged ≤9 years were used. Molecular analysis for the detection of ACE rs4646994 (I/D), ACE2 rs2106809 (C/T) and rs2285666 (G/A) alleles as well as ACE2 exons 1–4 polymorphisms was conducted on 300 samples. The D allele (54%,162/300) was the most dominant polymorphism observed in the ACE rs4646994 gene whilst the G (68%, 204/300) and T alleles (59.3%,178/300) were the most frequent ACE2 rs2285666 and rs2106809 polymorphisms observed. For the 300 samples sequenced for ACE2 exons 1–4, analyses were done on 268, 282 and 137 quality sequences for exons 1, 2 and 3–4 respectively. For exon 1, the mutation D38N (2.2%; 6/268) was the most prevalent. The S19P and E37K mutations previously reported to influence COVID-19 infections were observed at low frequencies (0.4%, 1/268 each). No mutations were observed in exon 2. The N121K/T variants were the most seen in exons 3–4 at frequencies of 5.1% (K121, 7/137) and 2.9% (T121, 4/137) respectively. Most of the variants observed in the exons were novel compared to those reported in other populations in the world. This is the first study to investigate the genetic diversity of ACE and ACE2 genes in Ghanaians. The observation of novel mutations in the ACE2 gene is suggesting selection pressure. The importance of the mutations for communicable and non-communicable diseases (malaria and COVID-19) are further discussed.

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.

Functional regulation of Alu element of human angiotensin-converting enzyme gene in neuron cells

The angiotensin-converting enzyme (ACE) insertion/deletion (I/D) genotype and its protein activity have been widely implicated to be associated with Alzheimer's disease (AD). However, whether the insertion sequence, Alu element, in intron 16 of the human ACE gene plays a functional role remains uncertain. To investigate the influence of the I/D polymorphism on ACE promoter, we recombined the I and D form fragments with the human ACE promoter sequence before the reporter gene in pSEAP-Basic2 vector. The effect of the Alu element on regulating the transcriptional activity of ACE promoter was examined using transient transfection in SH-SY5Y cells. We found that the I form fragment upregulated the transcriptional activity of ACE promoter by approximately 70% but that the D form fragment did not. Our study first reveals that Alu sequence in human ACE gene possesses a regulatory function on the ACE promoter activity in neuron. This novel finding bridges the gap between the association of ACE I/D genotype with AD, and suggests that Alu sequence is not merely a “junk” DNA in human ACE gene.

Functional Evaluation Of Angiotensin‐Converting Enzyme (ACE) Amino Acid Residues important for the interaction with its inhibitors

Hypertension is a worldwide health problem considered to be one of the greatest public health challenges. Since hypertension is a major risk factor for cardiovascular and renal disease, many studies have focused on the Renin‐Angiotensin System (RAS), an endocrine system where renin cleaves angiotensinogen and releases Angiotensin I (AI) which is converted into Angiotensin II (AII) by the action of Angiotensin Converting Enzyme I (ACE). The ACE has a large physiological importance being a target of several therapeutic studies. This work aims to investigate the role of amino acids residues Asp140, Gln259, Ala332, Ser 333, Gln 355, Thr 358, Phe435 and Arg 500, in the interaction with the ACE inhibitor lisinopril as well as other ones.. An analysis of sequence homology to the ACEs of Xenopus laevis, mouse, rat and human, human isoform N‐domain (ND) and isoforms of 65 and 90 kDa of rat showed a high conservation of amino acid residues proposed to be mutated. Primers containing the mutation were synthesized. Following, we used a vector containing the cDNA with the human ACE gene (pACE) to perform PCR reactions; then the products obtained from PCR reactions were digested with the enzyme DpnI and transformed in E. coli DH5α. Positive colonies had the plasmid extracted, sequenced and analyzed concerning the desired mutation. The ACE mutants will be analyzed related to enzyme‐substrate interaction as well as enzyme activity.

Gender Specific Association of Insertion/Deletion Polymorphism of the Human Angiotensin Converting Enzyme Gene with Essential Hypertension

The pattern of angiotensin-converting enzyme (ACE) gene insertion/deletion (I/D) polymorphism in the Indian population is poorly known. The population has cultural and linguistic differences and lived in an environment that varied significantly from one region to another. There is controversy regarding the association of the Angiotensin-converting enzyme insertion/deletion polymorphism with essential hypertension and variation in blood pressure. In the present study we examined the importance of ACE (I/D) polymorphism as a determinant of hypertension and to assess the potential modifying effect of gender on ACE gene in Indian population. The ACE I/ D polymorphism was assayed by PCR amplification of ACE gene in 200 hypertension patients and 200 controls. The genotypic and allelic frequencies were observed to be deviated significantly from Hardey-Weinberg equilibrium (p<0.05). The DD and ID genotypes were found to be strongly associated with hypertension in men with an odds ratio 2.25 (95% confidence level (CI), 1.14 to 4.42) and 2.20 (95% CI, 1.27 to 3.80) respectively, (p<0.01). Further, a linear relationship was observed between diastolic pressure and allele D in men but not in women. The data thus provide evidence in favor of an association of I/D polymorphism at the ACE locus (17q23) with essential hypertension. Moreover, these results highlight the potential importance of gender-dependent interactions between genetic background and expression of hypertensive phenotype. It further prompts the need for the confirmatory studies in large population-based samples.

Gender Specific Association of Insertion/Deletion Polymorphism of the Human Angiotensin Converting Enzyme Gene with Essential Hypertension

Gender Specific Association of Insertion/Deletion Polymorphism of the Human Angiotensin Converting Enzyme Gene with Essential Hypertension

Linkage of angiotensin I‐converting enzyme gene insertion/deletion polymorphism to the progression of human prostate cancer

Angiotensin-converting enzyme (ACE) degrades vasodilator kinins and generates angiotensin II (Ang II). It has been reported that ACE is synthesized by the prostate and that the AT-1 receptor subtype is the predominant prostatic Ang II receptor. A polymorphism in the human ACE gene has been described and the highest levels of circulating and tissue ACE activity are found in carriers of the DD genotype. In the present study, ACE genotypes were determined in 170 patients with prostate cancer and their association with disease progression was analysed. It was found that the DD genotype was present in 31 of 78 (39.8%) patients with advanced disease and in 19 of 82 (23.2%) with localized disease: this difference was statistically significant (OR = 2.18, 95% CI = 1.11-4.03; p = 0.024). Step-wise logistic regression analysis was used to identify predictive parameters of advanced disease and it was observed that the DD genotype (p = 0.002, OR = 5.4, 95% CI = 1.84-16.06), high-grade tumour (p < 0.001, OR = 8.04, 95% CI = 3.03-21.33), and high serum PSA (p < 0.001, OR = 10.87, 95% CI = 4.06-29.13) were significantly associated with advanced disease. The results of this study support the hypothesis that genetic factors related to ACE may influence the behaviour of human prostate cancer.

Angiotensin-converting enzyme and genetics at high altitude.

As part of the renin-angiotensin system (RAS), angiotensin-converting enzyme (ACE) plays a key role in circulatory homeostasis. ACE degrades vasodilator kinins and generates angiotensin II. A polymorphism in intron 16 of the human ACE gene has been identified in which the presence (insertion, I allele) rather than the absence (deletion, D allele) of a 287 bp fragment is associated with lower serum and tissue ACE activity. The I allele has been associated with some aspects of endurance performance, being found with excess frequency in elite distance runners, rowers, and other elite athletes. Mountaineers also demonstrate an allele skew with a significant excess of the I allele and II genotype in elite, male, British mountaineers who have ascended beyond 7000 m without the use of supplemental oxygen. This review evaluates the evidence for and against an association of the I allele with human endurance, and performance at high altitude. We conclude that the I allele does confer an advantage, most likely mediated via improved muscle efficiency with secondary benefits in terms of conservation of non-fat mass.

ACE gene polymorphism and cardiovascular diseases

The angiotensin converting enzyme (ACE) is an integral part of enzymatic cascades leading to generation of angiotensin II as well as degradation of bradykinin. For this reason, it represents an important part for the metabolism of 2 vasoactive peptides. Early in this decade, convincing experimental evidence demonstrated the induction of this enzyme in several pathophysiological conditions including myocardial infarction and left ventricular hypertrophy. In parallel, a deletion/insertion (D/I) polymorphism of the human ACE gene was discovered that was related to 14 to 50% of the interindividual variance of serum ACE activity. More recently, this polymorphism was implicated in the pathogenesis of a variety of cardiovascular disorders including myocardial infarction, left ventricular hypertrophy, hypertension as well as nephropathy.

The unknown alternative splicing generates a novel isoform of human angiotensin-converting enzyme as a soluble form

Human angiotensin-converting enzyme (ACE) gene exists in the chromosome 17, and two kinds of molecules are produced from the same gene locus according to the alternative splicing as the somatic and testis form. It is said theACE activity in serum derives from proteolytic release of the somatic ACE located in endothelial cell surface. V~ report here, in human somaticACE mRNA, the unrecognized alternative splicing occurs in common, and as a result, a new isoform of ACE is generated. The samples were Jurkat cell (humanT cell leukemia line) and peripheral blood leukocytes obtained healthy subjects.The mRNA was extracted from these cells, and RT-PCR was executed with the primer set in the 15th exon and the 18th exon.The electroophoresis of the PCR product visualized two bands of DNA fragment; one was the expected band derived from somaticACE mRNA, and the other was the unexpected, 150bp-longer one. This longer DNA fragment was subcloned and sequenced. As a result, the structure of this fragment was revealed to be exon15-exon16-exon17-intronf7-exon18 of human ACE gene, and a novel alternative splicing was confirmed.This alternative splicing arose a new stop codon immediately after the 17th exon, and it was surmised that a novel isoform of ACE was £1enerated as a soluble form which deleted the transmembrane portion and C domain of two active centers of somaticACE. This isoform mRNAwas also detected in lung, kidney, aorta and pancreas, and not detected in brain, heart, liver, skeletal muscle, testis and placenta by screening the human cDNA library of each organ. In leukocytes and pancreas, the expression level was about 20 percent of somaticACE, and much lower in lung, kidney and aorta. The other research group have reported that the transgenic mouse of the equivalent artificial molecule had shown a similar phenotype of theACE-knockout mouse, therefore this spontaneously expressed molecule in human is also expected to have similar functions in vivo. Further, we have investigated the relationship between this alternative splicing and theACE Insertion/Deletion poiymorphism in the 16th intron. At this moment, any correlation have been found within both phenomena. The 2nd Annual Scientific Meeting • JHFS 67

The Angiotensin-Converting Enzyme (ACE) Gene Insertion/Deletion Dimorphism Tracks with Higher Serum ACE Activities in Both Younger and Older Subjects

The absence of a 287 base pair alu sequence in the ACE gene (D allele) is associated with higher ACE levels than its presence (I allele) in adults. We carried out a case-control study of the ACE*I/D dimorphism in relation to circulating ACE activities to evaluate associations between the two variables in adults, compared to younger (18 years or less) individuals. Genotypes of the ACE*I/D dimorphism were determined on DNA samples from a population of 164 random (unrelated) Emirate nationals, composed of two groups: 112 subjects above 18 years of age (range=20-77 years), and 52 subjects of 18 years or less (range=1-18), and analyzed for putative associations with serum ACE activities. ACE*I/D genotypes of the 164 individuals were determined by assays based on polymerase chain reaction. ACE activities were determined on serum samples of these subjects by colorimetric assays. The D allele was associated with increased ACE values in both adult and younger individuals. Mean ACE activity levels associated with II, ID and DD genotypes, however, were 42%-61% higher in the 18 years and under group of subjects. The ACE*I/D marker accounted for 28% of the variance of the phenomenon determining ACE levels in adults, and for 30% among youngsters. The ACE*I/D dimorphism correlated strongly with circulating ACE activities in both adult and young Emirati subjects, and the corresponding mean ACE activities were significantly higher among the youngsters.

Angiotensin converting enzyme gene polymorphism in coronary artery disease: the Indian scenario.

Angiotensin converting enzyme is a key component of the renin angiotensin system that plays an important role in cardiovascular regulation. It seems to modulate cardiovascular growth by virtue of its role in the conversion of angiotensin I to angiotensin II and degradation of kinins. A deletion polymorphism localized in intron 16 of the human angiotensin converting enzyme gene, corresponding to a 287 bp long Alu repetitive sequence, was found to be associated with increased risk of myocardial infarction in various subgroups, including European, French and Japanese coronary patients. This angiotensin converting enzyme gene I/D polymorphism was examined by the polymerase chain reaction in a cross-sectional study of 201 healthy Indian subjects and 150 patients (angiographically proven cases of coronary artery disease) whose serum angiotensin converting enzyme levels were concomitantly measured. The D/D, I/D and I/I genotypes were found in 20.66%, 46.66% and 32.66% of the Indian coronary heart disease patients and in 23.38%, 49.75% and 26.86% of controls respectively. One of the reasons for not finding an association between the D allele and coronary artery disease in this study could be the ethnic heterogeneity and disease status heterogeneity among the patients and controls. However the phenotypic variance of serum angiotensin converting enzyme levels is strongly influenced by this polymorphism. In the Indian population, the angiotensin converting enzyme gene I/D polymorphism is not associated with risk for coronary artery disease although it is associated with plasma angiotensin converting enzyme activity. Hence the angiotensin converting enzyme gene I/D polymorphism does not seem to be a useful marker for coronary artery disease in the Indian population.

Characterization of polymorphisms IVS25AS-6A to G, C1237T and T3409C in the human angiotensin converting enzyme gene.

Characterization of polymorphisms IVS25AS-6A to G, C1237T and T3409C in the human angiotensin converting enzyme gene.

Angiotensin-Converting Enzyme Genotypes and Risk for Myocardial Infarction in Women

Objectives. We tested for an association between the angiotensin-converting enzyme (ACE) DD polymorphic genotype and myocardial infarction (MI) in a sample group composed exclusively of women.Background. The human ACE gene occurs with either an insertion (I allele) or a deletion (D allele) of a 287-base pair (bp) Aluelement. Part of the variance in serum ACE levels may be accounted for by this polymorphism. Also, the DD genotype has been associated with an increased risk of MI in predominantly male populations. However, the risk in women is poorly defined.Methods. Genomic DNA was extracted from buffy coat blood using a phenol/chloroform method. Angiotensin-converting enzyme alleles were identified using primers to bracket the insertion region in intron 16. Amplification using polymerase chain reaction allowed identification of a 490-bp (I allele) or a 190-bp (D allele) product, or both.Results. Allelic and genotypic frequencies in control subjects were similar to those reported in mostly male populations, and frequencies of genotypes were in the Hardy-Weinberg equilibrium. In contrast, the distribution of genotypes in patients with MI diverged from the equilibrium. Specifically, DD genotypic frequency was increased in women with (n = 141) versus without (n = 338) a previous MI (39% vs. 29%, odds ratio [OR] 1.54, 95% confidence interval 1.02 to 2.32, p < 0.04). Risk was particularly increased in women <60 years old (OR 2.04, p < 0.05). In contrast, the DD genotype did not predict angiographic coronary artery disease.Conclusions. Consistent with findings in male-dominated populations, a modest association of the ACE DD genotype with MI was found in women. The basis for this association requires further study.

Polymorphism of the angiotensin-converting enzyme gene and cardiovascular disease

The angiotensin-converting enzyme (ACE) is an integral part of two enzymatic cascades, one leading to the generation of angiotensin II and the other to the degradation of bradykinin. The great variety of cardiovascular effects mediated by these vasoactive peptides and the efficacy of ACE inhibitors in the treatment of hypertension and heart failure emphasize the prominent role of ACE in the cardiovascular system. Early in this decade convincing experimental evidence demonstrated the induction of this enzyme in several pathophysiological conditions, including myocardial infarction and left ventricular hypertrophy. In parallel, a deletion/insertion (D/I) polymorphism of the human ACE gene was characterized that is related to 14-50% of the interindividual variance in serum ACE activity. More recently this polymorphism has been implicated in the pathogenesis of a variety of cardiovascular disorders, including myocardial infarction, left ventricular hypertrophy, hypertension, diabetic and IgA nephropathy, carotid artery thickening, and lacunar cerebral stroke. However, the associations between the ACE D/I polymorphism and most of these conditions were found to be inconsistent when additional populations were investigated. This contribution reviews the current evidence on the relationship between the ACE D/I polymorphism and cardiovascular disease.

Deletion polymorphism in the angiotensin-converting enzyme gene is not associated with hypertension in a Gulf Arab population.

We have studied an insertion/deletion dimorphism in the human angiotensin-converting enzyme gene amongst UAE nationals from the Abu Dhabi Emirate. Our findings show lack of association between the I/D allele marker system and clinical diagnosis of essential hypertension, suggesting that variations of the angiotensin-converting enzyme gene do not play a major role in the determination of elevated blood pressure in this Arab population. This agrees with results reported on other ethnic groups.

Human ACE gene polymorphism and distilled water induced cough.

BACKGROUND: Inhibitors of angiotensin converting enzyme (ACE) cause a non-productive cough. The insertion/deletion polymorphism of ACE was used as a genetic marker to investigate the relationship between ACE genotype and...

Mistyping of the human angiotensin-converting enzyme gene polymorphism: frequency, causes and possible methods to avoid errors in typing

A polymorphism of the gene encoding the human angiotensin I-converting enzyme (ACE), which is defined by an insertion/deletion polymorphism in intron 16, has been identified as a candidate genetic locus in the development of cardiovascular and renal disease. We have demonstrated that the accuracy of ACE genotyping is critically dependent on the strategy of the PCR used in typing. Of 1238 individuals genotyped by a standard method, 335 were typed as DD, 645 as DI and 258 as II. However, when DD individuals were retyped using modified methods (including either 5% dimethyl sulphoxide, or a 'hot start') 35 of the original 335 samples (10.5%) were retyped as DI. In approximately half of these mistyped samples, PCR amplification was assessed as inefficient by the absence of a third faint heteroduplex band in a control ID sample: when the assay was repeated without any modifications, the mistyped samples were correctly genotyped. In the remainder, mistyping persisted. In these cases, the use of a third 'nested' PCR primer specific for the I allele was required for successful genotyping, providing a more reliable strategy without the need for further modification to the PCR technique. Our results suggest that the triple primer approach is the method of choice for accurate ACE genotyping.

Enhanced pressor response to angiotensin I in normotensive men with the deletion genotype (DD) for angiotensin-converting enzyme.

The insertion (I)/deletion (D) polymorphism of the human angiotensin-converting enzyme gene has emerged as a genetic risk factor for ischemic heart disease. However, the functional consequences of this polymorphism in humans are not known. Ten normotensive men with the DD genotype and 10 with the II genotype participated in a study in which pressor responses to stepwise infusions of incremental doses of angiotensin I (Ang I) and Ang II and Ang II production during Ang I infusion were measured. Pressor responses were expressed as PD20, which reflects the angiotensin dose required to raise mean blood pressure by 20 mm Hg. The PD20 for Ang I in subjects with the DD genotype was significantly lower than that in II genotype subjects (8.8 versus 14.8 ng/kg per minute, P = .0091), whereas the PD20 for Ang II between the two groups did not differ significantly. The ratio of PD20 for Ang I and Ang II in DD subjects was significantly lower than that in II subjects (0.85 versus 0.96, P = .0452), and the venous levels of Ang II during Ang I infusion in DD subjects were significantly higher than those in II subjects (P < .01). Our study has shown increased pressor responsiveness to Ang I, probably as a consequence of the generation of increased Ang II levels, in subjects homozygous for the DD allele of the angiotensin-converting enzyme gene. This result may be relevant to the reported adverse cardiovascular risk conferred by the D allele, as it provides a mechanistic rationale for the association between this polymorphism and cardiovascular disease.

PCR detection of the insertion/deletion polymorphism of the human angiotensin converting enzyme gene (DCP1) (dipeptidyl carboxypeptidase 1)

PCR detection of the insertion/deletion polymorphism of the human angiotensin converting enzyme gene (DCP1) (dipeptidyl carboxypeptidase 1)