Increased frequency of the DI genotype of the angiotensin-I converting enzyme and association of the II genotype with insulin resistance in polycystic ovary syndrome

ACE I/D gene polymorphisms and polycystic ovary syndrome manifestations

Objective

Polycystic ovary syndrome (PCOS) is a common multifactorial endocrine disorder affecting women of reproductive age. ACE enzyme is involved in the physiopathology of the ovarian system, and there are inconsistencies between studies regarding the association between ACE gene variants and PCOS. The objective of this study is to evaluate the association between ACE I/D gene polymorphisms and PCOS, as well as its clinical manifestations, in Iranian women with PCOS.

Design

This study included 140 patients with PCOS and 153 controls without the disease. Samples were collected from Yas Hospital Complex in Tehran-Iran during 2018 to 2022. Genomic DNA was obtained from whole blood samples using salt extraction, and genotyping was carried out using polymerase chain reaction (PCR).

Results

Variants of DD, ID, and II were observed in 31.4, 44.3, and 24.3% of PCOS, and 38.6, 44.1, and 17.2% of control group, respectively. The frequency of ACE gene variants did not differ between PCOS patients and control group. A significant difference was observed between the frequency of elevated LH to FSH ratio > 2 and ACE gene polymorphisms in patients with PCOS (OR: 0.32 (0.12-0.88), P value 0.024) with lower frequency observed in D allele carriers.

Conclusion

This study indicate that although ACE I/D variants frequency in PCOS women is similar to non-PCOS women, it may be involved in the pathogenesis of the disease through mechanisms regulating steroidogenesis in the ovary and suggests that ACE might be related to exacerbated clinical manifestations of PCOS which requires further investigations.

Angiotensin-Converting Enzyme (ACE) Insertion/Deletion (I/D) Polymorphism as a Conjoint Regulator of Coagulation, Fibrinolytic, and RAAS Pathway in Infertility and Associated Pregnancy Complications

Despite the increase in assisted reproductive technologies, the high rates of infertility and pregnancy complications are a major concern to infertility specialists worldwide. Infertility may be attributed to pregnancy complications like thrombophilia, preeclampsia and fibrin-induced recurrent pregnancy loss (RPL). Renin-angiotensin-aldosterone system (RAAS) directly or indirectly causes preeclampsia and thrombophilia through the fibrinolytic pathway that ultimately leads to RPL or infertility. The underlying mechanisms of this interaction are still unclear. The present comprehensive review is intended to demonstrate the role and interaction of RAAS and fibrinolytic pathways in pregnancy complications. How this interaction can induce pregnancy complications, and ultimately infertility, is also discussed in the light of current evidence. This study also presents common markers that link RAAS and fibrinolytic processes in developing thrombophilia, preeclampsia and RPL. The common link in these pathways is ACE gene I/D polymorphism. Apart from ACE, PAI-1, VIIa, XIIa, AT1R, AT1AA, and TF are common molecules that can delineate the underlying causes of pregnancy complications and infertility.

Association Between Angiotensin-Converting Enzyme Gene I/D Polymorphism and Polycystic Ovary Syndrome Susceptibility: a Meta-analysis

Rec ent studies have suggested a closer association between angiotensin-converting enzyme (ACE) gene polymorphisms and polycystic ovary syndrome (PCOS) risk, but the results were inconsistent. We conducted this meta-analysis to explore the precise associations between ACE gene I/D polymorphism and PCOS risk. Online electronic databases (PubMed, Embase, SCI index, CNKI, and Wanfang) were searched. Odds ratios (ORs) with 95% confidence interval (CIs) were calculated to assess the association between ACE gene I/D polymorphism and PCOS risk. In addition, heterogeneity, accumulative/sensitivity analysis, and publication bias were conducted to check the statistical power. Overall, 12 published case-control studies with 2248 patients and 1759 controls were included according to the criteria. Significant increased risk was found for PCOS susceptibility with I/D mutation (D vs. I: OR = 1.62, 95%CI = 1.24-2.11, P < 0.01, I² = 86.1%; DD vs. II: OR = 2.10, 95%CI = 1.35-3.27, P < 0.01, I² = 79.8%; ID + DD vs. II: OR = 1.57, 95%CI = 1.06-2.32, P = 0.02, I² = 79.3%; DD vs. II + ID: OR = 1.91, 95%CI = 1.39-2.65, P < 0.01, I² = 79.1%). Furthermore, some similar associations were also observed in subgroups. In summary, the current evidences indicated that ACE gene I/D polymorphism plays an important role in PCOS development, both in Asian and Caucasian descendants.

The role of polymorphism in various potential genes on polycystic ovary syndrome susceptibility and pathogenesis

Polycystic ovary syndrome (PCOS) is the most common endocrinopathies affecting the early reproductive age in women, whose pathophysiology perplexes many researchers till today. This syndrome is classically categorized by hyperandrogenism and/or hyperandrogenemia, menstrual and ovulatory dysfunction, bulky multi follicular ovaries on Ultrasonography (USG), and metabolic abnormalities such as hyperinsulinemia, dyslipidemia, obesity. The etiopathogenesis of PCOS is not fully elucidated, but it seems that the hypothalamus-pituitary-ovarian axis, ovarian, and/or adrenal androgen secretion may contribute to developing the syndrome. Infertility and poor reproductive health in women's lives are highly associated with elevated levels of androgens. Studies with ovarian theca cells taken from PCOS women have demonstrated increased androgen production due to augmented ovarian steroidogenesis attributed to mainly altered expression of critical enzymes (Cytochrome P450 enzymes: CYP17, CYP21, CYP19, CYP11A) in the steroid hormone biosynthesis pathway. Despite the heterogeneity of PCOS, candidate gene studies are the widely used technique to delineate the genetic variants and analyze for the correlation of androgen biosynthesis pathway and those affecting the secretion or action of insulin with PCOS etiology. Linkage and association studies have predicted the relationship between genetic variants and PCOS risk among families or populations. Several genes have been proposed as playing a role in the etiopathogenesis of PCOS, and the presence of mutations and/or polymorphisms has been discovered, which suggests that PCOS has a vital heritable component. The following review summarizes the influence of polymorphisms in crucial genes of the steroidogenesis pathway leading to intraovarian hyperandrogenism which can result in PCOS.

Relationship between adipocytokines and angiotensin converting enzyme gene insertion/deletion polymorphism in lean women with and without polycystic ovary syndrome

This study was designed to investigate the relationship between the levels of select adipocytokines (adiponectin, visfatin and apelin) and angiotensin in converting enzyme (ACE) gene insertion/deletion (ID) polymorphism in lean women with and without polycystic ovary syndrome (PCOS). The PCOS group (N = 94) was identified according to the Rotterdam criteria. The Control group (N = 68) included age- and body mass index (BMI)-matched healthy volunteers. Serum levels of adipocytokines were measured using enzyme immunoassays (EIA) and ACE genes were evaluated by polymerase chain reaction (PCR). The PCOS group, when compared to the Control group had lower adiponectin (p < .001) but higher visfatin (p < .001) and apelin (p = .003). There was no significant correlation of the levels of these adipocytokines with BMI, fasting glucose, fasting insulin or Homeostasis Model Assessment-Insulin Resistance (HOMA-IR). The PCOS and the Control groups also differed with regard to the ACE ID genotype distribution (p < .001). The ID, DD, and II genotype frequencies were, respectively, 34, 57 and 9% in the PCOS group and 49, 22 and 29% in the Control group. When stratified according to individual ID genotypes, the levels of adipocytokines in the PCOS and the Control groups remained significantly different. There was no statistically significant relationship between the levels of adipocytokines and ACE ID genotypes.

Polycystic ovarian syndrome: rs1799752 polymorphism of ACE gene

PURPOSE

To investigate the contribution of the deletion polymorphism and insertion (rs1799752) of the angiotensin converting enzyme (ACE) gene in the aetiology of Polycystic Ovarian Syndrome (PCOS).

METHODOLOGY

97 women diagnosed with PCOS who received care at the Gynaecology and Obstetrics clinic of the Hospital das Clínicas of UFTM, participated in this study. The control group consisted of 94 women. All participants were submitted to the collection of 10 mL of whole blood and the genomic DNA was obtained by the saline extraction method. The genotyping of the samples was performed by means of the Polymerase Chain Reaction (PCR). The statistics analyses were performed by descriptive analysis, univariate analysis and logistic regression model. The results were presented in odds ratio (OR) and confidence interval of 95% (CI-95%), with a significance level of 5% (p≤0.05).

RESULTS

There were no statistical differences between patients and controls for the genotypic (χ2 = 1.52, p = 0.47) and allelic frequencies (χ2 = 0.21, p = 0.76). The distribution of the genotypic frequency is not in HWE for patients (χ2 = 18.80, p <0.05) and for controls (χ2 = 6.85, p <0.05). In relation to the risk factors for the syndrome, the history of familial PCOS is more frequent between women with the syndrome.

CONCLUSION

In the study population, there was no association between I/D polymorphism of the ACE gene and PCOS.

Glioma Association and Balancing Selection of ZFPM2

ZFPM2, encoding a zinc finger protein and abundantly expressed in the brain, uterus and smooth muscles, plays important roles in cardiac and gonadal development. Abnormal expression of ZFPM2 in ovarian tumors and neuroblastoma has been reported but hitherto its genetic association with cancer and effects on gliomas have not been studied. In the present study, the hexamer insertion-deletion polymorphism rs71305152, located within a large haplotype block spanning intron 1 to intron 3 of ZFPM2, was genotyped in Chinese cohorts of glioma (n = 350), non-glioma cancer (n = 354) and healthy control (n = 463) by direct sequencing and length polymorphism in gel electrophoresis, and ZFPM2 expression in glioma tissues (n = 69) of different grades was quantified by real-time RT-PCR. Moreover, potential natural selection pressure acting on the gene was investigated. Disease-association analysis showed that the overall genotype of rs71305152 was significantly associated with gliomas (P = 0.016), and the heterozygous genotype compared to the combined homozygous genotypes was less frequent in gliomas than in controls (P = 0.005) or non-glioma cancers (P = 0.020). ZFPM2 mRNA expression was negatively correlated with the grades of gliomas (P = 0.002), with higher expression levels in the low-grade gliomas. In the astrocytoma subtype, higher ZFPM2 expression was also correlated with the rs71305152 heterozygous genotype (P = 0.028). In addition, summary statistics tests gave highly positive values, demonstrating that the gene is under the influence of balancing selection. These findings suggest that ZFPM2 is a glioma susceptibility gene, its genotype and expression showing associations with incidence and severity, respectively. Moreover, the balancing selection acting on ZFPM2 may be related to the important roles it has to play in multiple organ development or associated disease etiology.

Current issues in medically assisted reproduction and genetics in Europe: research, clinical practice, ethics, legal issues and policy. European Society of Human Genetics and European Society of Human Reproduction and Embryology

In March 2005, a group of experts from the European Society of Human Genetics and European Society of Human Reproduction and Embryology met to discuss the interface between genetics and assisted reproductive technology (ART), and published an extended background paper, recommendations and two Editorials. Seven years later, in March 2012, a follow-up interdisciplinary workshop was held, involving representatives of both professional societies, including experts from the European Union Eurogentest2 Coordination Action Project. The main goal of this meeting was to discuss developments at the interface between clinical genetics and ARTs. As more genetic causes of reproductive failure are now recognised and an increasing number of patients undergo testing of their genome before conception, either in regular health care or in the context of direct-to-consumer testing, the need for genetic counselling and preimplantation genetic diagnosis (PGD) may increase. Preimplantation genetic screening (PGS) thus far does not have evidence from randomised clinical trials to substantiate that the technique is both effective and efficient. Whole-genome sequencing may create greater challenges both in the technological and interpretational domains, and requires further reflection about the ethics of genetic testing in ART and PGD/PGS. Diagnostic laboratories should be reporting their results according to internationally accepted accreditation standards (International Standards Organisation - ISO 15189). Further studies are needed in order to address issues related to the impact of ART on epigenetic reprogramming of the early embryo. The legal landscape regarding assisted reproduction is evolving but still remains very heterogeneous and often contradictory. The lack of legal harmonisation and uneven access to infertility treatment and PGD/PGS fosters considerable cross-border reproductive care in Europe and beyond. The aim of this paper is to complement previous publications and provide an update of selected topics that have evolved since 2005.

Do ACE I/D gene polymorphism serve as a predictive marker for age at onset in PCOS?

BACKGROUND

Polycystic ovary syndrome (PCOS) is an endocrine disorder exhibiting variable age at onset of clinical features allied with complex diseases in the later life. ACE is a pleiotropic molecule associated with various pathophysiological functions. The present study was aimed to establish the frequency of ACE I/D gene polymorphism in patients and controls and to assess the influence of this polymorphism on anthropometric and various clinical features of the condition.

METHODS

ACE I/D genotyping was carried out in 259 PCOS patients and 315 healthy ultrasound scanned women of South Indian origin.

RESULTS

The distribution of DD, ID and II genotypes in patients was 39, 37 and 24 %, whereas in the controls it was 31, 51 and 18 % respectively. Significant difference was observed in the genotypic frequency distributions between the patients and controls, however the allelic frequencies did not vary between the groups (p>0.05). Quartile analysis revealed preponderance of DD genotype in the first two quartiles and a linear increase of II genotype from first to the last quartiles. Further, Multiple Logistic regression analysis revealed significant association of ACE I/D gene polymorphism with acanthosis and age at onset (AAO) of the syndrome (p<0.05).

CONCLUSION

The present study is the first report to highlight the predisposing role of DD and protective role of ID genotype towards PCOS. Patients with single or double dose of D allele may develop PCOS symptoms at an early age and also significantly associated with acanthosis, a marker of insulin resistance.