PCOS and peripheral AMH levels in relation to FSH receptor gene single nucleotide polymorphisms

Genetic Variants of Steroidogenesis and Gonadotropin Pathways and Polycystic Ovary Syndrome Susceptibility: A Systematic Review and Meta-analysis

Genetic variants are predisposing factors to polycystic ovary syndrome (PCOS), a multifactorial condition that often gets triggered due to various environmental factors. The study investigates the association of the variants of genes that are involved in the steroidogenesis pathway or gonadotropin pathway with the risk of PCOS. Appropriate keywords for predetermined genes were used to search in PubMed, Google Scholar, Science Direct, and Central Cochrane Library up to January 11, 2023. PROSPERO (CRD42022275425). Inclusion criteria: (a) case-control study; (b) genotype or allelic data. Exclusion criteria were: (a) duplicate studies; (b) clinical trials, systematic reviews, meta-analysis or conference abstract, case reports; (c) other than the English language; (d) having insufficient data; e) genetic variants for which meta-analysis has been reported recently and does not have a scope of the update. Various genetic models were applied as per data availability. Overall 12 variants of 7 genes were selected for the analysis. Relevant data were extracted from 47 studies which include 10,584 PCOS subjects and 16,150 healthy controls. Meta-analysis indicates a significant association between TOX3 rs4784165 [ORs = 1.08, 95% CI (1.00-1.16)], HMGA2 rs2272046 [ORs = 2.73, 95% CI (1.97-3.78)], YAP1 rs1894116 [OR = 1.22, 95% CI (1.13-1.33)] and increased risk of PCOS. Whereas FSHR rs2268361 [ORs = 0.84, 95% CI (0.78-0.89)] is associated with decreased PCOS risk. When sensitivity analysis was carried out, the association became significant for CYP19 rs700519 and FSHR rs6165 under an additive model. In addition, C9Orf3 rs3802457 became significantly associated with decreased PCOS risk with the removal of one study. Insignificant association was observed for CYP19A (rs2470152), FSHR (rs2349415, rs6166), C9Orf3 (rs4385527), GnRH1 (rs6185) and risk of PCOS. Our findings suggest association of CYP19A (rs700519), TOX3 (rs4784165), HMGA2 (rs2272046), FSHR (rs6165, rs2268361), C9orf3 (rs3802457), and YAP1 (rs1894116) with risk for PCOS.

Association Between Follicle-Stimulating Hormone Receptor (FSHR) rs6166 and Estrogen Receptor 1 (ESR1) rs2234693 Polymorphisms and Polycystic Ovary Syndrome Risk, Phenotype, and Reproductive Outcomes in an Infertile Portuguese Population

INTRODUCTION

Polycystic ovary syndrome (PCOS) is a common endocrine disorder often leading to anovulatory infertility. PCOS pathophysiology is still unclear and several potential genetic susceptibility factors have been proposed. The effect of polymorphisms in two genesrelated to follicular recruitment and development, the follicle-stimulating hormone receptor (FSHR) and the estrogen receptor 1 (ESR1), have been studied in different populations with contradictory results.

AIMS

To evaluate the influence of FSHR rs6166 (c.2039A>G) and of ESR1 rs2234693 (Pvull c.453-397 T > C) polymorphisms on PCOS risk, phenotype, and response to controlled ovarian stimulation (COS).

MATERIALS AND METHODS

Genotyping of the FSHR rs6166 and the ESR1 rs2234693 polymorphisms was performed in PCOS women and a control group undergoing in vitro fertilization (IVF). Demographic, clinical, and biochemical data, genotype frequency, and IVF outcomes were compared between groups.

RESULTS

We evaluated 88 PCOS women and 80 controls. There was no significant difference in the genotype distribution of FSHR rs6166 polymorphism between PCOS women and controls (AA 31.8%/AS 48.9%/SS 19.3% in PCOS women vs AA 37.5%/AS 40.0%/SS 22.5% in controls; p = 0.522). The same was true for the ESR1 rs2234693 (CC 24.1%/CT 46.0%/TT 29.9% in PCOS women vs CC 18.8%/CT 48.8%/TT 32.5% in controls; p = 0.697). In PCOS women, we found higher follicle-stimulating hormone (FSH) levels on the third day of the menstrual cycle associated with the SS variant of the FSHR polymorphism (9.2 vs 6.2 ± 1.6 and 5.6 ± 1.6 mUI/mL; p = 0.011). We did not find other associations between the baseline hormonal parameters, antral follicle count, and response measures to COS with FSHR or ESR1 genotypes. We found, however, a need for higher cumulative doses of FSH for COS in patients with the SS variant of the FSHR rs6166 polymorphism (1860.5 ± 627.8 IU for SSvs 1498.1 ± 359.3 for AA and 1425.4 ± 474.8 for SA; p = 0.046 and p = 0.046).

CONCLUSION

Our data suggest that in the population, FSHR rs6166and ESR1 rs2234693 polymorphisms do not influence the risk of developing PCOS nor do they influence the patient's phenotype and IVF success. However, the SS variant of the FSHR rs6166 polymorphism may be associated with FSH resistance requiring higher FSH doses for COS.

Role of Single Nucleotide Variants in FSHR, GNRHR, ESR2 and LHCGR Genes in Adolescents with Polycystic Ovary Syndrome

Background: Polycystic ovary syndrome (PCOS) is the most common endocrinopathy in women, affecting up to 16.6% of reproductive-age women. PCOS symptoms in adolescents comprise oligomenorrhoea/amenorrhoea and biochemical and/or clinical hyperandrogenism. Long-term health risks of PCOS patients include infertility, metabolic syndrome, type 2 diabetes and cardiovascular disease. Genetic factors have been proven to play a role in development of the syndrome and its symptoms. Objective: To investigate single nucleotide variants (SNVs) in the GNRHR, ESR2, LHCGR and FSHR genes in adolescent patients with PCOS and their association with PCOS symptoms. Methods: We conducted a cross-sectional study comprising of 152 adolescents: 63 patients with PCOS, 22 patients at risk of developing PCOS and 67 healthy controls. Participants were recruited from out-patients attending a gynaecologist at the Children’s Clinical University Hospital, Riga, Latvia, between January 2017 and December 2020. Genomic DNA was extracted from whole blood, and SNVs in the GNRHR, ESR2, LHCGR and FSHR genes were genotyped. The distributions of SNV genotypes were compared among the three groups and genotype-phenotype associations within the PCOS group were evaluated. Results: No statistically significant differences were found in the distributions of genotypes for GNRHR (rs104893837), ESR2 (rs4986938), LHCGR (rs2293275) and FSHR (rs6166, rs6165, rs2349415) among PCOS patients, risk patients and healthy controls. Within the PCOS group, ESR2 rs4986938 minor allele homozygous patients had a significantly higher level of total testosterone than major allele homozygous patients and heterozygous patients. A significantly higher total testosterone level was also observed in PCOS patients carrying the LHCGR rs2293275 minor allele compared with major allele homozygous patients. Conclusions: The SNVs ESR2 rs4986938 and LHCGR rs2293275 play a role in the phenotypic characteristics of PCOS. To fully uncover their influence on the development of PCOS and its symptoms, further studies of larger cohorts and a follow up of this study sample through to adulthood are required. Furthermore, studies of adolescent PCOS patients conducted prior to the latest European Society of Human Reproduction and Embryology (ESHRE) criteria (2018) should be re-evaluated as the study groups might include risk patients according to these updated criteria, thereby potentially significantly impacting the published results.

Follicle Stimulating Hormone Receptor (FSHR) Polymorphisms and Polycystic Ovary Syndrome (PCOS)

Polycystic ovary syndrome (PCOS) is the commonest endocrine abnormality in women of reproductive age typically presenting with chronic oligo- or anovulation, clinical, or biochemical hyperandrogenism and polycystic ovarian morphology (PCOM). Restoring mono-ovulation is the ultimate goal of ovulation induction and most women do respond to ovulation inducing agents causing their Follicle-stimulating hormone (FSH) levels to rise. Familial clustering and the results from twin studies strongly support an underlying genetic basis for PCOS. Recent Genome wide association studies (GWAS) have identified several genetic variants being genome wide significantly associated with PCOS. Amongst those are variants in or near the Luteinizing hormone (LH) and FSH receptor genes as well as a variant in the FSH-β gene. The aim of this review is to summarize the available evidence as to whether single nucleotide polymorphisms are able to modify the PCOS phenotype or whether they constitute a risk factor for the syndrome. Data on the role of FSHR polymorphisms in PCOS are conflicting. It seems that in large Chinese studies FSHR polymorphisms are not associated with either PCOS risk or with PCOS treatment outcome. However, in large scale studies in Caucasians these polymorphisms seem to influence the risk of having PCOS. Moreover, these studies also showed that some polymorphisms might affect some clinical features of PCOS as well as treatment outcome. Although most research has focussed on the role of FSHR polymorphisms there seems to be also some evidence showing that single nucleotide polymorphisms (SNPs) in the LHCG-Receptor as well as those in FSH-β gene might also alter the phenotype of PCOS. In conclusion most studies confirm that FSHR polymorphisms do alter the phenotype of PCOS in that they either alter the response to exogenous FSH or hat they increase the risk of having PCOS.

Identification of selected genetic polymorphisms in polycystic ovary syndrome in Sri Lankan women using low cost genotyping techniques

Background

Polycystic ovary syndrome (PCOS), the commonest endocrine disorder affecting young women, appears to be a multigenic trait with contributing genes being unclear. Hence, analysis of polymorphisms in multiple candidate genes is required. Currently available genotyping methods are expensive, time-consuming with limited analytical sensitivity.

Aim

(i) Develop and validate high resolution melting (HRM) assay and allele-specific real-time quantitative PCR (AS-qPCR) for genotyping selected SNPs associated with PCOS.

(ii) Identify selected SNPs and their association with a Sri Lankan cohort of well-characterized PCOS.

Methods

DNA was extracted from women with well-characterized PCOS from adolescence (n = 55) and ethnically matched controls (n = 110). FTO (Fat mass and obesity associated gene; rs9939609), FSHB (Follicle stimulating hormone beta subunit; rs6169), FSHR (Follicle stimulating hormone receptor; rs6165/rs6166), and INSR (Insulin receptor; rs1799817) genes were genotyped using HRM assay. GnRH1 (Gonadotropin releasing hormone; rs6185), LHB (Luteinizing hormone beta subunit; rs1800447/rs34349826) and LHCGR (Luteinizing hormone/choriogonadotropin receptor; rs2293275) genes were genotyped using AS-qPCR method. Genotyping results were validated using Sanger sequencing.

Results

A significant association was observed within FTO gene polymorphism (rs9939609) and PCOS. Genotype frequency of FTO gene (rs9939609)—cases versus controls were TT-36.4% vs.65.4% (p<0.05), AT-23.6% vs.20.9%, AA-40% vs.13.6% (p<0.05). Genotype frequencies of the SNPs GnRH1 (rs6185), FSHB (rs6169), FSHR (rs6165 & rs6166), LHB (rs1800447 & rs34349826), LHCGR (rs2293275) and INSR (rs1799817) were not significantly different between cases and controls (p>0.05). Only the mutant alleles were observed for LHB rs1800447 and rs34349826 SNPs in both groups. The HRM and AS-qPCR assay results had 100% concordance with sequencing results.

Conclusions

FTO gene rs9939609 polymorphism is significantly more prevalent among Sri Lankan PCOS subjects while the other selected SNPs of HPG axis genes and INSR gene showed no association. HRM and AS-qPCR assays provide a reliable, fast and user-friendly genotyping method facilitating wider implication in clinical practice.

FSH receptor gene p. Thr307Ala and p. Asn680Ser polymorphisms are associated with the risk of polycystic ovary syndrome

PURPOSE

The purpose of this study was to investigate whether the follicle-stimulating hormone receptor (FSHR) gene p. Thr307Ala (c.919A>G, rs6165) and p. Asn680Ser (c.2039A>G, rs6166) polymorphisms are associated with susceptibility to polycystic ovary syndrome (PCOS).

METHODS

Genotyping was performed in 377 women with PCOS and 388 age-matched controls. Difference in the genotype distribution was assessed using a Fisher's exact or chi-square test, and continuous variables were compared using a Student's t test. To evaluate the association between the presence of PCOS status and SNP, logistic regression analyses were performed.

RESULTS

Linkage disequilibrium between the two polymorphisms was approximately complete (r ² = 99%). The genotype distributions of the PCOS group significantly differed from those of the control group (Thr/Thr, Thr/Ala, and Ala/Ala frequencies were 38.5, 46.7, and 14.9% for the PCOS group and 46.6, 45.4, and 8.0% for the controls, respectively, P = .005; Asn/Asn, Asn/Ser, and Ser/Ser frequencies were 39.5, 47.2, and 13.3% for the PCOS group and 46.4, 45.4, and 8.2% for the controls, respectively, P = .035). Using the wild-type genotypes as the references, the odds ratios that a woman has PCOS were 2.23 (95% confidence intervals 1.38-3.68) for the Ala/Ala genotype, 1.87 (95% confidence intervals 1.14-3.06) for the Ser/Ser genotype, and 1.96 (95% confidence intervals 1.19-3.24) for the homozygous variant combination (Ser/Ser-Ala/Ala). However, there were no significant differences in serum hormonal, ovarian, and metabolic markers according to each genotype.

CONCLUSIONS

Findings of this study suggest a significant association between FSHR gene p. Thr307Ala or p. Asn680Ser coding sequence change and PCOS. The variant homozygote genotype results in a higher risk of PCOS.

Family-based analysis of eight susceptibility loci in polycystic ovary syndrome

Polycystic ovary syndrome (PCOS) is a complex endocrine disorder that is proposed to have a genetic basis. A recent genome-wide association study (GWAS) identified eight new risk loci that are independently associated with PCOS. To further validate the findings, a total of 321 case-parent trios (963 participants) who had a proband affected with PCOS were recruited for the family-based study. The transmission disequilibrium test (TDT) was used to analyze associations between PCOS and ten single nucleotide polymorphisms (SNPs) mapped to eight new susceptibility loci. Significant differences in transmission were observed for the SNPs rs2349415 (located in the FSHR gene, P = 0.0001) and rs3802457 (located in the C9orf3 gene, P = 0.0001), even after correction for multiple testing bias. The present data provides further evidence for an association between two susceptibility loci, 2p16.3 and 9q22.32, and PCOS. Follow-up functional studies on the FSHR and C9orf3 genes are required to understand their roles in PCOS development.

Association between two polymorphisms of follicle stimulating hormone receptor gene and susceptibility to polycystic ovary syndrome: a meta-analysis

OBJECTIVE

To investigate the association between two polymorphisms of follicle stimulating hormone receptor (FSHR) gene and polycystic ovary syndrome (PCOS) susceptibility.

METHODS

Case-control studies on relationship of Thr307Ala and Asn680Ser polymorphisms in FSHR gene and PCOS susceptibility were searched from PubMed, ISI web of knowledge, EBSCO, and China National Knowledge Infrastructure (CNKI) databases up to March 21, 2013. The pooled odds ratio (OR) and 95% confidence interval (CI) were calculated using fixed- or random-effect model based on heterogeneity test in 5 genotype models analyses.

RESULTS

A total of 11 studies were included in the Meta-analysis. The random-effect analysis showed Asn680Ser was significantly associated with the reduced susceptibility to PCOS with dominant model (Asn/Asn+Asn/Ser vs. Ser/Ser, OR=0.83, 95% CI: 0.69-1.00), recessive model (Asn/Asn vs. Asn/Ser+ Ser/Ser, OR=0.84, 95% CI: 0.72-0.98), homozygote comparison (Asn/Asn vs. Ser/Ser, OR=0.79, 95% CI: 0.63-0.98), and the allele contrast (Asn vs. Ser, OR=0.87, 95% CI: 0.79-0.97) respectively(P=0.02, I(2)=56.0%), being protective factors for PCOS. However, no significant associations were found between Thr307Ala and PCOS.

CONCLUSION

There might be a significant association between Asn680Ser polymorphism and PCOS.

Leutinizing hormone/choriogonadotropin receptor and follicle stimulating hormone receptor gene variants in polycystic ovary syndrome

PURPOSE

Previous studies identified follicle-stimulating hormone receptor (FSHR) and luteinizing hormone/choriogonadotropin receptor (LHCGR) genes as polycystic ovary syndrome (PCOS) susceptibility loci, which was dependent on the racial/ethnic background of studied population. We investigated the association of genetic variants in FSHR and LHCGR with PCOS in Bahraini Arab women.

METHODS

A retrospective case-control study, involving 203 women with PCOS, and 211 age- and ethnically-matched control women. FSHR and LHCGR genotyping was done by allelic exclusion method (real-time PCR).

RESULTS

Significantly lower frequencies of heterozygous LHCGR rs7371084 and FSHR rs11692782 genotype carriers were seen between women with PCOS vs. controls, and increased frequency of heterozygous homozygous LHCGR rs4953616 genotype carriers were detected between women with PCOS compared to control women. Limited linkage disequilibrium was noted among LHCGR and FSHR SNPs, and 2 blocks were constructed: the first (Block 1) spanning 61 kb contained the six tested LHCGR SNPs, and the second (Block 2) spanning 298 kb contained four of the five tested FSHR SNPs. Higher frequency of LHCGR GTCAAG haplotype was seen in women with PCOS compared to controls; the frequencies of the remaining LHCGR haplotypes, and all FSHR haplotypes were similar between cases and controls.

CONCLUSION

This is the first study to confirm the association of novel LHCGR (rs7371084, rs4953616) and FSHR (rs11692782) SNPs with PCOS. The differential association of LHCGR and FSHR variants with PCOS confirms the racial/ethnic contribution to their association with PCOS.

Two follicle-stimulating hormone receptor polymorphisms and polycystic ovary syndrome risk: a meta-analysis

The aim of this study was to explore the association between follicle stimulating hormone receptor (FSHR) Thr307Ala and Asn680Ser polymorphisms and susceptibility to polycystic ovary syndrome (PCOS). A comprehensive literature search for relevant studies was conducted on Google Scholar, PubMed, the Chinese National Knowledge Infrastructure (CNKI) and the Chinese Biomedical Literature Database (CBM). This meta-analysis was performed using the STATA 11.0 software and the pooled odds ratio (OR) with 95% confidence interval (CI) was calculated. Ten case-control studies were included in this meta-analysis. However, meta-analysis results showed no association between both FSHR Thr307Ala polymorphism and Asn680Ser polymorphism and susceptibility to PCOS. Stratified analysis of ethnicities also showed no association. In conclusion, the present study suggested that the FSHR polymorphisms were not associated with an increased risk of PCOS and larger-scale studies of populations are needed to explore the roles played by FSHR polymorphisms during the pathogenesis of PCOS.

Anti-Müllerian hormone (AMH) downregulation in late antral stages is impaired in PCOS patients. A study in normo-ovulatory and PCOS patients undergoing in vitro maturation (IVM) treatments

PURPOSE

To prospectively study the AMH expression and secretion pattern in mural granulosa cells (GCs) and follicular fluid (FF) from small follicles and medium follicles that were collected from normo-ovulatory (NO) and polycystic ovary syndrome (PCOS) patients undergoing in vitro maturation (IVM) treatments.

METHODS

FF AMH levels and mRNA expression of mural GCs were measured in small (≤ 10 mm) and medium size follicles (11-15 mm) obtained from IVM treatments and large size follicles (≥ 16 mm) obtained from in vitro fertilization treatments.

RESULTS

First, we show that AMH expression and protein level in the FF of NO patients were significantly higher in the small size follicles than in the medium and large size follicles (p < 0.003). We could not demonstrate these differences in PCOS patients. Second, we found significantly higher levels of AMH protein and mRNA in the large and medium (but not small) size follicles of PCOS patients compared to follicles from NO patients (p < 0.02). Finally, we observed a positive correlation between FF AMH of small and medium size follicles from NO patients and serum AMH (p < 0.03 and p < 0.0002, respectively).

CONCLUSIONS

Our data demonstrate a pathological dysregulation of AMH expression and secretion in follicles from PCOS patients and emphasize the association between the physiological downregulation of AMH and follicular antral health.

Association study between FSHR Ala307Thr and Ser680Asn variants and polycystic ovary syndrome (PCOS) in Northern Chinese Han women

BACKGROUND

Polycystic ovary syndrome (PCOS) is a common complex genetic endocrinopathy. It has high heritability, and twin studies indicate that it is a complex polygenic disorder. Searching for major genes of PCOS is crucial to clarify its molecular pathogenesis. A previous genome-wide association study in Chinese women with PCOS identified a region on chromosome 2p16.3 that encodes the follicle-stimulating hormone receptor (FSHR) genes as a reproducible PCOS susceptibility locus. In the present study, we performed a replication analysis of the association between two common variants of the FSHR gene and PCOS in Northern Chinese Han women.

RESULTS

We recruited 384 unrelated PCOS patients and 768 healthy individuals from the Shaanxi province in the northern part of China. Two polymorphisms (Ala307Thr and Ser680Asn) of the FSHR gene and the clinical characteristics of the study subjects were analyzed in the case-control sample. The frequency of FSHR Ala307Thr and Ser680Asn variants along with the haplotype was not significantly different between the PCOS patients and the controls; however, the Ser680 variants may be associated with high levels of FSH and low E2 levels.

CONCLUSION

The variant of Ser680 was not associated with PCOS but it may be related to high FSH levels. The present study suggests that the two variants of the FSHR gene are not a causative factor of PCOS in Northern Chinese Han women.