Estrogen receptor-1 genetic polymorphisms for the risk of premature ovarian failure and early menopause

Association of Polymorphisms in FSHR, ESR1, and BMP15 with Primary Ovarian Insufficiency and Meta-Analysis

Primary ovarian insufficiency (POI) can lead to menstrual disturbance, resulting in ovarian dysfunction before age 40. Prevalence of POI is usually less than 1%; however, ethnicity or population characteristics may affect prevalence. POI is a heterogeneous disease that results from abnormalities in immunological and hormonal factors. Genetic factors can also contribute to POI. Here, we examine FSHR, ESR1, and BMP15 polymorphisms in patients with POI, and controls. We examined a hormonal gene that is important for pregnancy, follicle-stimulating hormone receptor (FSHR), as well as estrogen receptor 1 (ESR1), and associated it with FSHR expression, ovulation rate, and bone morphogenetic protein 15 (BMP15). We examined 139 Korean patients under age 40 with POI, and 350 Korean control participants without POI. Genotyping was performed by a polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and TaqMan assays. Each identified genotype was subjected to statistical analysis to determine the odds ratios (ORs) and 95% confidence intervals (CIs). In combination genotype analyses, FSHR rs6165 A > G combined with ESR1 rs9340799 A > G, AG/GG (OR: 5.693; 95% CI: 1.088-29.792), as well as FSHR rs6166 A > G combined with ESR1 rs9340799 C > T, AG/GG (OR: 5.940; 95% CI: 1.134-31.131), were significantly associated with POI prevalence. Furthermore, an FSHR rs6165 A > G and BMP rs17003221 C > T, AG/CC combination was associated with POI prevalence (OR: 1.874; 95% CI: (1.059-3.316; p-value: 0.031)). In meta-analysis, FSHR rs6165 AA vs. AG + GG is associated with POI (p = 0.0013), and ESR1 rs2234693 AA vs. AG + GG is also associated with POI (p = 0.0101). Here, we compared the genotypes of FSHR, ESR1, and BMP15 in patients with POI, and controls. We found significant differences in genotype combinations between polymorphisms in FSHR and other genes. Through meta-analysis, we found that ESR1 rs9340799 and rs2234693 are associated with POI prevalence, and that BMP15 rs17003221 increases POI risk. These findings help to improve POI diagnosis in Korean women.

Genes linked with early menopause and the pathogenesis of its associated diseases: a systematic review

Background

Menopause is a biological process when a woman’s reproductive capability is no longer functional. A naturally or artificially caused premenopausal is known as early menopause occurs between the ages 40–45, which substantially impacts fertility and disease influenced by genetic plus environmental factors and their interactions. Women in early menopause are at greater risk of cardiovascular disease, general mortality, neurological disorders, osteoporosis, mental illness, and other problems.

Main body

A PubMed search of the electronic literature database yielded articles on early menopause and disease etiology. Several unique genes were identified, such as ESR1, ESR2, CYP1B1, BRSK1, HK3, andTMEM150B are associated with early menopause, and research focused on case-control, cohort, and cross-sectional studies are finding novel predisposition loci for early menopause.

Conclusion

The current study’s focus is to understand better the genetic aspects of early menopause. This knowledge will help researchers enhance EM etiology and identify biomarkers that may detect early development of the disease, allowing women at risk to begin family planning earlier.

Estrogen Biosynthesis and Signal Transduction in Ovarian Disease

Estrogen mainly binds to estrogen receptors (ERs) to regulate menstrual cycles and reproduction. The expression of ERalpha (ERα), ERbeta (ERβ), and G-protein-coupled estrogen receptor (GPER) mRNA could be detected in ovary, suggesting that they play an important role in estrogen signal transduction in ovary. And many studies have revealed that abnormal expression of estrogen and its receptors is closely related to ovarian disease or malignant tumors. With the continuous development and research of animal models, tissue-specific roles of both ERα and ERβ have been demonstrated in animals, which enable people to have a deeper understanding of the potential role of ER in regulating female reproductive diseases. Nevertheless, our current understanding of ERs expression and function in ovarian disease is, however, incomplete. To elucidate the biological mechanism behind ERs in the ovary, this review will focus on the role of ERα and ERβ in polycystic ovary syndrome (PCOS), ovarian cancer and premature ovarian failure (POF) and discuss the major challenges of existing therapies to provide a reference for the treatment of estrogen target tissue ovarian diseases.

Sex-dependent effect of APOE on Alzheimer's disease and other age-related neurodegenerative disorders

The importance of apolipoprotein E (APOE) in late-onset Alzheimer's disease (LOAD) has been firmly established, but the mechanisms through which it exerts its pathogenic effects remain elusive. In addition, the sex-dependent effects of APOE on LOAD risk and endophenotypes have yet to be explained. In this Review, we revisit the different aspects of APOE involvement in neurodegeneration and neurological diseases, with particular attention to sex differences in the contribution of APOE to LOAD susceptibility. We discuss the role of APOE in a broader range of age-related neurodegenerative diseases, and summarize the biological factors linking APOE to sex hormones, drawing on supportive findings from rodent models to identify major mechanistic themes underlying the exacerbation of LOAD-associated neurodegeneration and pathology in the female brain. Additionally, we list sex-by-genotype interactions identified across neurodegenerative diseases, proposing APOE variants as a shared etiology for sex differences in the manifestation of these diseases. Finally, we present recent advancements in 'omics' technologies, which provide a new platform for more in-depth investigations of how dysregulation of this gene affects the development and progression of neurodegenerative diseases. Collectively, the evidence summarized in this Review highlights the interplay between APOE and sex as a key factor in the etiology of LOAD and other age-related neurodegenerative diseases. We emphasize the importance of careful examination of sex as a contributing factor in studying the underpinning genetics of neurodegenerative diseases in general, but particularly for LOAD.

Zebrafish as a model for studying ovarian development: Recent advances from targeted gene knockout studies

Ovarian development is a complex process controlled by precise coordination of multiple factors. The targeted gene knockout technique is a powerful tool to study the functions of these factors. The successful application of this technique in mice in the past three decades has significantly enhanced our understanding on the molecular mechanism of ovarian development. Recently, with the advent of genome editing techniques, targeted gene knockout research can be carried out in many species. Zebrafish has emerged as an excellent model system to study the control of ovarian development. Dozens of genes related to ovarian development have been knocked out in zebrafish in recent years. Much new information and perspectives on the molecular mechanism of ovarian development have been obtained from these mutant zebrafish. Some findings have challenged conventional views. Several genes have been identified for the first time in vertebrates to control ovarian development. Focusing on ovarian development, the purpose of this review is to briefly summarize recent findings using these gene knockout zebrafish models, and compare these findings with mammalian models. These established mutants and rapid development of gene knockout techniques have prompted zebrafish as an ideal animal model for studying ovarian development.

The genetics of premature ovarian failure: current perspectives

Premature ovarian failure (POF) is a common cause of infertility in women, characterized by amenorrhea, hypoestrogenism, and elevated gonadotropin levels in women under the age of 40. Many genes have been identified over the past few years that contribute to the development of POF. However, few genes have been identified that can explain a substantial proportion of cases of POF. The unbiased approaches of genome-wide association studies and next-generation sequencing technologies have identified several novel genes implicated in POF. As only a small proportion of genes influencing idiopathic POF have been identified thus far, it remains to be determined how many genes and molecular pathways may influence idiopathic POF development. However, owing to POF’s diverse etiology and genetic heterogeneity, we expect to see the contribution of several new and novel molecular pathways that will greatly enhance our understanding of the regulation of ovarian function. Future genetic studies in large cohorts of well-defined, unrelated, idiopathic POF patients will provide a great opportunity to identify the missing heritability of idiopathic POF. The identification of several causative genes may allow for early detection and would provide better opportunity for early intervention, and furthermore, the identification of specific gene defects will help direct potential targets for future treatment.

Association study of TGFBR2 and miR-518 gene polymorphisms with age at natural menopause, premature ovarian failure, and early menopause among Chinese Han women

Age at natural menopause (ANM), a highly heritable phenotype, has been identified to be closely associated with major hormone-related diseases, including breast cancer and gynecological cancers. We previously identified an important role for the transforming growth factor, β receptor II (TGFBR2) gene polymorphisms in breast cancer susceptibility among Asian women. Considering the important role of ANM in breast carcinogenesis, we hypothesized that TGFBR2 signals were involved in the formation of natural menopause.In a population-based study of 1844 Chinese women, we evaluated the effect of the genetic polymorphisms of TGFBR2 and miR-518 to determine if they are associated with ANM, premature ovarian failure (POF), and early menopause (EM) risk.No significant differences in the distribution of body mass index, education levels, smoking, drinking, and hypertension were detected between POF and EM cases and controls except for POF cases that were older (P = 0.015) than controls and more likely to have dyslipidemia (P = 0.002). The results showed that miR-518 rs7256241 was significantly associated with ANM. The carriers of minor allele G of rs7256241 have significantly higher ANM than those of the major allele homozygotes TT (β = 0.385, P = 0.035). TGFBR2 rs3773661 was significantly associated with POF, with odds ratio (OR) (95% confidence intervals [CIs]) of 0.66 (0.47-0.94) associated with per minor allele C (P = 0.023). The quartiles of genetic risk score were significantly associated with POF (OR, 1.27; 95% CI, 1.02-1.58; Ptrend = 0.034). Sensitivity analyses confirmed the robustness of these findings and no significant interactions were detected.This study provides evidence to implicate TGFBR2 and miR-518 gene polymorphisms as novel susceptibility factors for ANM, POF, and EM in Asians. Further research on these genetic regions will enhance our understanding of the genetic basis of natural menopause.

Genomic markers of ovarian reserve

Ovarian reserve and its utilization, over a reproductive life span, are determined by genetic, epigenetic, and environmental factors. The establishment of the primordial follicle pool and the rate of primordial follicle activation have been under intense study to determine genetic factors that affect reproductive lifespan. Much has been learned from transgenic animal models about the developmental origins of the primordial follicle pool and mechanisms that lead to primordial follicle activation, folliculogenesis, and the maturation of a single oocyte with each menstrual cycle. Recent genome-wide association studies on the age of human menopause have identified approximately 20 loci, and shown the importance of factors involved in double-strand break repair and immunology. Studies to date from animal models and humans show that many genes determine ovarian aging, and that there is no single dominant allele yet responsible for depletion of the ovarian reserve. Personalized genomic approaches will need to take into account the high degree of genetic heterogeneity, family pedigree, and functional data of the genes critical at various stages of ovarian development to predict women's reproductive life span.

Lack of association between ESR1 gene polymorphisms and premature ovarian failure in Serbian women

OBJECTIVE

It has previously been reported that estrogen receptor-alpha (ERα) gene (ESR1: estrogen receptor 1) polymorphisms are associated with premature ovarian failure (POF). The aim of this study was to investigate whether these genetic polymorphisms of ESR1 are associated with POF in Serbian women.

METHODS

A series of 197 POF cases matched with 547 fertile controls was recruited by the Institute for Endocrinology, Diabetes and Metabolic Disorders of Serbia between 2007 and 2010. Genomic DNA was extracted from saliva using Oragene® DNA sample collection kits. Two single-nucleotide polymorphisms (SNPs), PvuII and XbaI, in ESR1 were genotyped by dynamic allele-specific hybridization. Haplotype analyses were performed with the restriction fragment length polymorphism method. SNP and haplotype effects were analyzed by logistic regression models.

RESULTS

No significant difference was found in the distribution of ESR1 PvuII and XbaI polymorphisms or haplotypes between the POF and control groups.

CONCLUSION

The two ESR1 SNPs, PvuII and XbaI, are not commonly associated with POF in Serbian women and may not contribute to the genetic basis of the condition.

Estrogen receptor α gene (ESR1) polymorphisms associated with idiopathic premature ovarian failure in Chinese women

OBJECTIVE

To evaluate the relationship between Estrogen receptor α gene (ESR1) polymorphisms and idiopathic premature ovarian failure (POF) in Chinese women.

METHODS

155 idiopathic POF and 150 healthy controls were recruited in this study. All subjects were analyzed at the PvuII and XbaI loci of the ESR1 gene using polymerase chain reaction (PCR)-restriction fragment length polymorphism (RFLP).

RESULTS

The frequency of the P allele of the PvuII polymorphisms was 38.1% in POF women, which was significantly higher than controls (28.0%) (p = 0.008). And for the XbaI polymorphisms, the X allele was 21.0% in POF patients, compared to 13.3% in control women (p = 0.013). Carriers of the PP genotype had higher increased risk of POF than those of the pp genotypes (p = 0.011), whereas in three genotypes of the XbaI polymorphisms, no difference was found in the prediction value of POF. In addiction, the P-X haplotype was associated with a significantly increased risk for idiopathic POF.

CONCLUSION

These data suggest that the PvuII and XbaI polymorphisms of ESR1 gene are associated with POF, which may be a potential genetic risk factor of idiopathic POF. More researches are needed to determine whether the findings are generalizable to other populations.

Risk of premature ovarian failure is associated to the PvuII polymorphism at estrogen receptor gene ESR1

PURPOSE

Estrogen plays an important role in the human reproductive system and it action is mediated mainly by two specific receptors: α (ERα) and β (ERβ). There were described polymorphic variants in ESR1 and ESR2 genes and studies showed controversial results regarding their association with premature ovarian failure. We aimed to determine the prevalence of ESR1 and ESR2 polymorphisms in Brazilian patients and controls. After associate the polymorphisms with premature ovarian failure (POF).

METHODS

Genetic association study was performed with 70 women with POF and 73 normally menopaused controls. Detection of ESR1 (PvuII/and XbaI) and ESR2 (AluI and RsaI) gene polymorphisms were performed using TaqMan PCR. The single-nucleotide polymorphism (SNPs) and haplotype effects were analyzed by multivariate logistic regression and haplotype analysis and a p-value < 0.05 was considered significant.

RESULTS

Individual SNP analysis revealed that PvuII polymorphism was statistically associated with POF (p = 0.034) under a recessive model. Regarding XbaI, AluI and RsaI SNPs, no statistical difference was observed between POF group and controls (p = 0.575, p = 0.258 and p = 0.483, respectively). Combined genotypes of ESR1 and ESR2 polymorphisms did not identify a risk haplotype associated with POF.

CONCLUSION

In Brazilian population evaluated results have demonstrated that the genetic variation in ESR1 gene (PvuII polymorphism) is associated to POF risk.

A chromosome 19 locus positively influences the number of retrieved oocytes during stimulated cycles in Brazilian women

PURPOSE

To evaluate if several genetic loci that are associated with variation in normal menopause age and early menopause can account for a poor response to controlled ovarian stimulation.

METHODS

A total of 71 patients age ≤35 years old who were undergoing intracytoplasmic sperm injection were genotyped for four genetic variants that are associated with normal variation in menopausal age and early menopause. The patients were divided into two groups based upon treatment response: a poor responder group (PR group, n = 21) and a normal responder group (NR group, n = 50). The genetic variants rs244715, rs9379896, rs4806660 and rs16991615 were analyzed.

RESULTS

There was no significant difference in the incidence of the genetic variants between the NR and PR group. The risk allele for the chromosome 19 variant (rs4806660) demonstrated a protective effect for a poor ovarian response. The presence of a risk allele was associated with an increased response to COS, which resulted in an elevated number of follicles (Coef: 2.54, P = 0.041) and retrieved oocytes (Coef: 1.41, P = 0.041).

CONCLUSIONS

The genetic variants rs244715, rs9379896, rs4806660 and rs16991615 are not risk factors for poor ovarian response in Brazilian women. In contrast, rs4806660 is associated with higher number of follicles and retrieved oocytes. rs4806660 may be associated with an increased response to gonadotrophin stimulation in this population.

ESR1, HK3 and BRSK1 gene variants are associated with both age at natural menopause and premature ovarian failure

Background

Premature ovarian failure (POF) is a complex and heterogeneous disorder that is influenced by multiple genetic components. Numerous candidate gene studies designed to identify POF susceptibility loci have been published, but most positive findings have not been confirmed in follow up studies. We sought to determine if sequence variants previously associated with age at natural menopause (AANM) or early menopause (EM) contribute as well to genetic susceptibility to POF.

Methods

Our study was performed on 371 unrelated idiopathic women with POF and 800 women controls, all Chinese Han. Thirty six SNPs from previous genome-wide association studies (GWAS) responsible for AANM or EM and 3 additional SNPs in ESR1, and 2 additional SNPs in PTHB1 were tested using the Sequenom MassARRAY iPLEX platform for genotyping.

Results

Three SNPs - rs2278493 in HK3, rs2234693 in ESR1 and rs12611091 in BRSK1 - showed nominally significant association with POF. Thus, a plausible relationship could exist between ESR1, BRSK1, HK3 and POF.

Conclusions

This largest association study undertaken to determine correlation between POF and AANM/EM revealed three significant SNPs (rs2278493, rs2234693, and rs12611091). All are associated with not only AAWM and EM but also POF. Insights into shared genetic susceptibility between POF and AANM/EM will provide novel entry points for unraveling genetic mechanism involved in ovarian reserve and oocyte aging processes.

Chromosomal abnormalities in women with premature ovarian failure

Premature ovarian failure is a complex disorder that results in the early loss of ovarian function; however this disease must be separated from early menopause because these patients can sporadically ovulate and in literature are described pregnancies. The aetiology and the patho-physiology of premature ovarian failure are still matter of debate, but is commonly accepted that genetic factors play an important role. This review is aimed to present an overview of known inherited factor implied in the pathogenesis of this disorder to help physician in the counselling of affected pregnant women.

Epistasis between CYP19A1 and ESR1 polymorphisms is associated with premature ovarian failure

Because an interaction between CYP19A1 and ESR1 may play a key role in determining the level of circulating E2 by way of the hypothalamus-hypophysis-ovarian axis, the effect of single nucleotide polymorphism (SNP)-SNP interactions between CYP19A1 and ESR1 on the development of premature ovarian failure (POF) was investigated by comparing the polymorphisms of 98 patients with POF and 218 matched controls of Korean ethnicity. A significant association with POF risk was found for the combined genetic effect between the CYP19A1 3'untranslated region (UTR) SNP rs10046 (CT+TT) and the intronic ESR1 SNP rs1569788 (CC) genotype (odds ratio=12.67, 95% confidence interval: 1.61-99.71), and a statistically significant association was also observed between POF and the CYP19A1 3'UTR SNP rs10046 under a dominant model (odds ratio=2.51, 95% confidence interval: 1.33-4.76), suggesting that epistasis between ESR1 and CYP19A1 may be involved in the regulation of folliculogenesis.