Genetic complexity of FSH receptor function

Follicle-Stimulating Hormone Receptor (FSHR) Ser680Asn Genotype Does Not Affect the Follicular Fluid Hormonal Profile in Stimulated Cycles Using Different Gonadotropin Preparations for Ovulation Induction: A Pilot Study

BACKGROUND

The existing literature lacks consensus on the effectiveness of utilizing polymorphisms to enhance outcomes in in vitro fertilization (IVF), particularly regarding ovulation induction protocols, oocyte and embryo quality, and pregnancy rates. Therefore, the present pilot study aims to assess whether the composition of different gonadotropin preparations affects the ovarian stimulation protocol concerning follicle-stimulating hormone receptor (FSHR) Ser680Asn genotypes (Ser/Ser, Ser/Asn, and Asn/Asn), in terms of ovulation induction parameters, including oocyte maturation rate, embryo quality, and pregnancy rate.

METHODOLOGY

A total of 94 IVF patients underwent treatment using a GnRH antagonist protocol with four distinct gonadotropin preparations: HMG, HMG/hCG, rFSH, and rFSH/hCG. Follicular fluid (FF) samples were pooled for each patient for analysis.

RESULTS

No statistical differences in the FF hormonal profile (progesterone, testosterone, androstenedione, estradiol, FSH, hCG) among the FSHR genotypes were reported either separately for each protocol or in combination for the four different preparations of gonadotropins. The maturation rate of MII oocytes and embryo quality did not differ among women carrying either Ser/Ser, Ser/Asn, or Asn/Asn genotype (p-value=0.475, and p-value=1.000, respectively). Moreover, no statistically significant correlation was revealed among Ser/Ser, Ser/Asn, and Asn/Asn carriers and pregnancy rate (p = 0.588).

CONCLUSIONS

FF hormonal analysis of women undergoing IVF using different ovulation induction protocols and carrying either Ser/Ser, Ser/Asn, or Asn/Asn genotype revealed no significant correlations, in terms of maturation rate of MII oocytes, embryo quality, and pregnancy rate, indicating that the FSHR Ser680Asn genotype does not constitute a biomarker for a positive pregnancy outcome. Therefore, the existence of a different mechanism for the expression of FSHR Ser680Asn genotypes in the FF hormonal profile related to stimulated cycles is implied.

EGF-driven EGFR/miR-27b-3p/FOXO1 promotes rat FSH synthesis and secretion

The adenopituitary secretes follicle-stimulating hormone (FSH), which plays a crucial role in regulating the growth, development, and reproductive functions of organisms. Investigating the process of FSH synthesis and secretion can offer valuable insights into potential areas of focus for reproductive research. Epidermal growth factor (EGF) is a significant paracrine/autocrine factor within the body, and studies have demonstrated its ability to stimulate FSH secretion in animals. However, the precise mechanisms that regulate this action are still poorly understood. In this research, in vivo and in vitro experiments showed that the activation of epidermal growth factor receptor (EGFR) by EGF induces the upregulation of miR-27b-3p and that miR-27b-3p targets and inhibits Foxo1 mRNA expression, resulting in increased FSH synthesis and secretion. In summary, this study elucidates the precise molecular mechanism through which EGF governs the synthesis and secretion of FSH via the EGFR/miR-27b-3p/FOXO1 pathway.

Analyzing the Impact of FSHR Variants on Polycystic Ovary Syndrome-a Case-Control Study in Punjab

Polycystic ovary syndrome (PCOS) is an endocrine-metabolic syndrome that involves hyperandrogenism, menstrual irregularities, and/or small cysts in one or both ovaries which might lead to infertility in women. The genetics of PCOS is heterogenous with the involvement of several genes reported in the hypothalamic-pituitary-gonadal axis. Follicular growth and steroidogenesis regulation are both critically dependent on follicle-stimulating hormone (FSH). The variants of FSHR cause abnormal folliculogenesis, steroidogenesis, and oocyte maturation at various stages of growth and may render women more susceptible to PCOS development. The present case-control study evaluated the association of FSHR rs6165 and rs6166 variants with PCOS. A total of 743 females were recruited. PCR-RFLP method was used for the genotypic analysis of FSHR polymorphisms. Obesity was examined according to the categorization of body mass index (BMI) and waist-hip ratio (WHR). Biochemical analysis, including a lipid profile, LH, FSH, and testosterone levels, was done in both PCOS women and controls. BMI and WHR revealed a statistically significant difference between PCOS cases and controls. Overall, levels of HDL were significantly lower, whereas cholesterol, triglycerides, LDL, and VLDL levels were higher in PCOS women (p < 0.05). The genotypic and allelic frequencies of rs6165 and rs6166 did not demonstrate significant differences when PCOS women were compared with the control group. However, clinical features of PCOS including gonadotropic hormone (FSH), hyperandrogenism, and dyslipidemia were significantly correlated with variants of FSHR. The present study concludes that rs6165 and rs6166 were significantly related to clinical features of PCOS, regardless of providing direct disease risk.

The Polymorphism Asn680Ser on the FSH Receptor and Abnormal Ovarian Response in Patients with Normal Values of AMH and AFC

After the controlled ovarian stimulation (COS), the number of cumulus oocyte complexes collected is lower than predicted. The aim of this study is to understand if there is a possible reason for that deficient ovarian response. It was hypothesized that this is associated with the SNP (single-nucleotide polymorphism) of the FSH receptor (FSHr), specifically c.2039A > G, resulting in Asn680Ser. Two groups of patients were enrolled for this purpose: the normal (n = 36) and abnormal responses (n = 31). To predict the number of retrievable oocytes, according to the anti-Mũllerian hormone (AMH) and the antral follicle count (AFC), the following formula was applied in a log scale: the number of oocytes retrieved = 2.584 − 0.015 × (age) − 0.035 × (FSH) + 0.038 × (AMH) + 0.026 × (AFC). Then, when the number of oocytes collected was less than 50% of the calculated value, it was proposed that the patients result in an abnormal response. DNA sample blood was collected from the women, and then the genetic assessment for the Asn680Ser of the FSHr was evaluated in both groups. The differences between the two categories were statistically analyzed with an independent samples t test, a Mann−Whitney U test and a Chi-squared test. In a patient with an abnormal response, a significant prevalence of the amino acid serine at position 680 of the FSHr compared to the counterpart group (p < 0.05) was detected. In conclusion, according to the results, the genetic evaluation of the FSHr could represent an accurate and predictive feature for patients undergoing assisted reproductive technology treatment.

A GWAS in Idiopathic/Unexplained Infertile Men Detects a Genomic Region Determining Follicle-Stimulating Hormone Levels

CONTEXT

Approximately 70% of infertile men are diagnosed with idiopathic (abnormal semen parameters) or unexplained (normozoospermia) infertility, with the common feature of lacking etiologic factors. Follicle-stimulating hormone (FSH) is essential for initiation and maintenance of spermatogenesis. Certain single-nucleotide variations (SNVs; formerly single-nucleotide polymorphisms [SNPs]) (ie, FSHB c.-211G > T, FSHR c.2039A > G) are associated with FSH, testicular volume, and spermatogenesis. It is unknown to what extent other variants are associated with FSH levels and therewith resemble causative factors for infertility.

OBJECTIVE

We aimed to identify further genetic determinants modulating FSH levels in a cohort of men presenting with idiopathic or unexplained infertility.

METHODS

We retrospectively (2010-2018) selected 1900 men with idiopathic/unexplained infertility. In the discovery study (n = 760), a genome-wide association study (GWAS) was performed (Infinium PsychArrays) in association with FSH values (Illumina GenomeStudio, v2.0). Minor allele frequencies (MAFs) were analyzed for the discovery and an independent normozoospermic cohort. In the validation study (n = 1140), TaqMan SNV polymerase chain reaction was conducted for rs11031005 and rs10835638 in association with andrological parameters.

RESULTS

Imputation revealed 9 SNVs in high linkage disequilibrium, with genome-wide significance (P < 4.28e-07) at the FSHB locus 11p.14.1 being associated with FSH. The 9 SNVs accounted for up to a 4.65% variance in FSH level. In the oligozoospermic subgroup, this was increased up to 6.95% and the MAF was enhanced compared to an independent cohort of normozoospermic men. By validation, a significant association for rs11031005/rs10835638 with FSH (P = 4.71e-06/5.55e-07) and FSH/luteinizing hormone ratio (P = 2.08e-12/6.4e-12) was evident.

CONCLUSIONS

This GWAS delineates the polymorphic FSHB genomic region as the main determinant of FSH levels in men with unexplained or idiopathic infertility. Given the essential role of FSH, molecular detection of one of the identified SNVs that causes lowered FSH and therewith decreases spermatogenesis could resolve the idiopathic/unexplained origin by this etiologic factor.

Polycystic Ovarian Syndrome: A Complex Disease with a Genetics Approach

Polycystic ovarian syndrome (PCOS) is a complex endocrine disorder affecting females in their reproductive age. The early diagnosis of PCOS is complicated and complex due to overlapping symptoms of this disease. The most accepted diagnostic approach today is the Rotterdam Consensus (2003), which supports the positive diagnosis of PCOS when patients present two out of the following three symptoms: biochemical and clinical signs of hyperandrogenism, oligo, and anovulation, also polycystic ovarian morphology on sonography. Genetic variance, epigenetic changes, and disturbed lifestyle lead to the development of pathophysiological disturbances, which include hyperandrogenism, insulin resistance, and chronic inflammation in PCOS females. At the molecular level, different proteins and molecular and signaling pathways are involved in disease progression, which leads to the failure of a single genetic diagnostic approach. The genetic approach to elucidate the mechanism of pathogenesis of PCOS was recently developed, whereby four phenotypic variances of PCOS categorize PCOS patients into classic, ovulatory, and non-hyperandrogenic types. Genetic studies help to identify the root cause for the development of this PCOS. PCOS genetic inheritance is autosomal dominant but the latest investigations revealed it as a multigene origin disease. Different genetic loci and specific genes have been identified so far as being associated with this disease. Genome-wide association studies (GWAS) and related genetic studies have changed the scenario for the diagnosis and treatment of this reproductive and metabolic condition known as PCOS. This review article briefly discusses different genes associated directly or indirectly with disease development and progression.

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.

The FSHR G-29A variant is not associated with the ovarian response to exogenous FSH stimulation

A common genetic variant in the follicle stimulating hormone receptor gene (FSHR) 5'-untranslated region has been previously reported to influence FSHR gene expression. However, studies on the ovarian response to exogenous gonadotropin stimulation are limited. The aim of this study was to evaluate the association of variants at positions -29 of the FSHR gene with the ovarian response to exogenous FSH stimulation in Chinese women. The genotypes of the FSHR gene were assayed using the Sequenom MassARRAY system. Total RNA and protein was extracted from granulosa cells, and FSHR expression at the mRNA and protein levels was assessed using quantitative PCR and western blotting. Our data revealed that there was no association between the FSHR genotype at the -29 position and the outcome of controlled ovarian stimulation. The expression of FSHR, at both the mRNA and protein levels, was similar amongst the different FSHR genotypes assessed, but was significantly reduced in the low responders. These results indicate that the variants caused by mutations at position -29 are not associated with ovarian response, and the low ovarian response to gonadotropin stimulation may be caused by decreased FSHR expression.

The Role of the Guanosine Nucleotide-Binding Protein in the Corpus Luteum

The corpus luteum is a temporary endocrine gland in the ovary. In the ovarian cycle, repeated patterns of specific cellular proliferation, differentiation, and transformation occur that accompany the formation and regression of the corpus luteum. Molecular mechanism events in the ovarian microenvironment, such as angiogenesis and apoptosis, are complex. Recently, we focused on the role of RAS protein in the ovarian corpus luteum. RAS protein plays a vital role in the modulation of cell survival, proliferation, and differentiation by molecular pathway signaling. Additionally, reproductive hormones regulate RAS activity in the cellular physiological function of ovarian follicles during pre-ovulatory maturation and ovulation. Thus, we have reviewed the role of RAS protein related to the biological events of the corpus luteum in the ovary.

Unraveling the Balance between Genes, Microbes, Lifestyle and the Environment to Improve Healthy Reproduction

Humans’ health is the result of a complex and balanced interplay between genetic factors, environmental stimuli, lifestyle habits, and the microbiota composition. The knowledge about their single contributions, as well as the complex network linking each to the others, is pivotal to understand the mechanisms underlying the onset of many diseases and can provide key information for their prevention, diagnosis and therapy. This applies also to reproduction. Reproduction, involving almost 10% of our genetic code, is one of the most critical human’s functions and is a key element to assess the well-being of a population. The last decades revealed a progressive decline of reproductive outcomes worldwide. As a consequence, there is a growing interest in unveiling the role of the different factors involved in human reproduction and great efforts have been carried out to improve its outcomes. As for many other diseases, it is now clear that the interplay between the underlying genetics, our commensal microbiome, the lifestyle habits and the environment we live in can either exacerbate the outcome or mitigate the adverse effects. Here, we aim to analyze how each of these factors contribute to reproduction highlighting their individual contribution and providing supporting evidence of how to modify their impact and overall contribution to a healthy reproductive status.

The Role of FSHR SNPs and AMH in Follicular Fluid and Serum in Ovarian Response during COS: A Pilot Study

Background

Several studies have investigated on the polymorphism Ser680Asn of FSHR and its use as a predictive indicator of response to an IVF/ICSI protocol. Furthermore, measurement of AMH in serum and follicular fluid is a useful prognostic indicator for the outcome of an assisted reproduction attempt. The purpose of this study is to examine the FSH receptor Ser680Asn polymorphism in combination with AMH levels in both serum and follicular fluid, on the day of oocyte collection.

Materials and Methods

A total of 32 women who underwent IVF/ICSI were included. Women were grouped into 2 groups: those who received rFSH (n = 11) and those who received hMG (n = 21). Serum AMH was measured on day 3 of the cycle, and AMH in the follicular fluid on the day of oocyte retrieval; the same day peripheral blood was collected for the genotyping of Ser680Asn.

Results

No statistical significant difference was found between serum AMH and follicular fluid AMH regarding the FSH receptor genotype for the Ser680Asn polymorphism. Regarding the sAMH/ffAMH ratio in the 3 genotypes, the value was lower in Asn/Asn women than Ser/Ser and Ser/Asn, but no statistical difference was obtained. Women who carry the Ser allele have a higher number of follicles, retrieved oocytes, and mature oocytes than women who do not contain the Ser allele. Women with AMH < 2.22 ng/ml presented lower AMH follicular fluid levels and lower serum AMH/follicular fluid AMH ratio in a statistically significant manner. Concerning the genotype for the polymorphism Ser680Asn of FSHR in relation to AMH levels, no statistically significant differences were found.

Conclusions

The identification of polymorphisms, such as Ser680Asn of FSHR, along with the determination of endocrine markers in the follicular fluid, such as AMH, could lead at some point, to the personalized therapy setting per woman.

The 2039 A/G FSH receptor gene polymorphism influences glucose metabolism in healthy men

OBJECTIVE

To assess the role of c. 2039 A/G (p. Asp680Ser) (rs6166) and c. -29 G/A (rs1394205) follicle-stimulating hormone receptor (FSHR) gene single nucleotide polymorphisms (SNPs) in a cohort of healthy men.

METHODS

One-hundred twenty-seven healthy men underwent evaluation of the anthropometric parameters, assessment of metabolic and lipid profile, measurement FSH serum levels, and genotyping of both the aforementioned FSHR SNPs. Data grouped according to the FSHR rs6166 or rs1394205 genotypes underwent to statistical analysis.

MAIN RESULTS

The three groups of men for each FSHR SNP did not differ statistically significantly for body mass index and serum FSH levels. As for FSHR rs6166 SNP, glucose levels were significantly lower in men with the GG genotype compared with those with the AA genotype. Men with AG had lower insulin levels and HOMA index values compared with those carrying the genotype AA (p < 0.05). The GG group showed a negative correlation between serum FSH levels and insulin and between serum FSH levels and HOMA index (p < 0.05). In contrast, men grouped according to the FSHR rs1394205 genotype showed no significant difference in blood glucose, serum insulin levels, and HOMA index. The AG group showed a negative correlation between FSH insulin and between serum FSH levels and HOMA index (p < 0.05).

CONCLUSIONS

Men with the genotype GG of the FSHR rs6166 SNP have lower blood glucose levels than those with the AA genotype. Their FSH levels inversely correlated with insulin and HOMA index. In contrast, the genotype FSHR rs6166 A/G did not reveal any role of FSH on glucose metabolism in healthy men. The inverse relationship between FSH and insulin or HOMA index in the group with the genotype GG of the FSHR rs6166 SNP suggests a possible cross-talk between FSH and insulin.

Pregravid contraceptive use and fecundability: prospective cohort study

OBJECTIVE

To evaluate the association between pregravid use of a variety of contraceptive methods and subsequent fecundability.

DESIGN

Prospective cohort study.

SETTING

Denmark and North America, 2007-19.

PARTICIPANTS

17 954 women who had tried to conceive for up to six menstrual cycles at study entry. At baseline, participants reported their contraceptive histories, and personal, medical, and lifestyle characteristics.

MAIN OUTCOME MEASURES

Pregnancy, determined by bimonthly follow-up questionnaires for up to 12 months.

RESULTS

Approximately 38% (n=6735) of participants had recently used oral contraceptives, 13% (n=2398) had used long acting reversible contraceptive methods, and 31% (n=5497) had used barrier methods. Women who had recently stopped using oral contraceptives, the contraceptive ring, and some long acting reversible contraceptive methods experienced short term delays in return of fertility compared with users of barrier methods. Use of injectable contraceptives was associated with decreased fecundability compared with use of barrier methods (fecundability ratio 0.65; 95% confidence interval 0.47 to 0.89). Users of injectable contraceptives had the longest delay in return of normal fertility (five to eight menstrual cycles), followed by users of patch contraceptives (four cycles), users of oral and ring contraceptives (three cycles), and users of hormonal and copper intrauterine devices and implant contraceptives (two cycles). Lifetime length of use of hormonal contraceptive methods was not associated with fecundability.

CONCLUSIONS

Use of some hormonal contraceptive methods was associated with delays in return of fertility, with injectable contraceptives showing the longest delay. The findings indicated little or no lasting effect of long term use of these methods on fecundability.

Combined Effects of the FSHR 2039 A/G and FSHR -29 G/A Polymorphisms on Male Reproductive Parameters

PURPOSE

The aim of this study was to evaluate the combined effect of FSHR 2039 A/G and FSHR -29 G/A single nucleotide polymorphisms (SNPs) on the male reproductive function in a cohort of Sicilian men.

MATERIALS AND METHODS

One-hundred thirty Sicilian men were enrolled and underwent blood withdrawal for hormone measurement and FSHR 2039 A/G and FSHR -29 G/A SNP genotyping, testicular volume evaluation by ultrasound scan, and semen analysis. A meta-analysis of the FSHR -29 G/A SNP, evaluated in a previous study of the Sicilian population was done.

RESULTS

No genotype of the FSHR 2039 A/G SNP correlated with serum follicle-stimulating hormone (FSH) levels, testicular volume, sperm concentration, and total sperm count. In contrast, normozoospermic men with FSHR -29 GG and FSHR -29 GA genotypes had significantly lower sperm concentrations compared to men with the FSHR -29 AA genotype. The other sperm parameters did not show any significant difference. The meta-analysis showed no significant difference in serum FSH levels, testicular volume, sperm concentration, and total sperm count between FSHR -29 GG and FSHR -29 AA in Sicilian men. No difference was found even when the two SNPs were evaluated in combination. However, this combination was present, as expected, only in a low proportion (3.8%) of the men studied.

CONCLUSIONS

The SNPs FSHR 2039 A/G and FSHR -29 G/A in combination did not seem to have any effect on male reproductive function in a cohort of Sicilian men. The effect of these SNPs has only been studied in granulosa cells so far. Further studies on their role in Sertoli cells are needed.

Does the FSHB c.-211G>T polymorphism impact Sertoli cell number and the spermatogenic potential in infertile patients?

BACKGROUND

A genetic variant within the FSHB gene can deviate FSH action on spermatogenesis. The c.-211G>T FSHB single nucleotide polymorphism impacts FSHB transcription and biosynthesis due to interference with the LHX3 transcription factor binding. This SNP was previously shown to be strongly associated with lowered testicular volume, reduced sperm counts, and decreased FSH levels in patients carrying one or two T-alleles.

OBJECTIVE

To determine the impact of the SNP FSHB c.-211G>T on Sertoli cell (SC) number, Sertoli cell workload (SCWL) and thereby spermatogenic potential.

MATERIAL AND METHODS

Testicular biopsies of 31 azoospermic, homozygous T patients (26 non-obstructive azoospermia (NOA), and five obstructive azoospermia (OA)) were matched to patients with GG genotype. Marker proteins for SC (SOX9), spermatogonia (MAGE A4), and round spermatids (CREM) were used for semi-automatical quantification by immunofluorescence. SCWL (number of germ cells served by one SC) was determined and an unbiased clustering on the patient groups performed.

RESULTS

Quantification of SC number in NOA patients did not yield significant differences when stratified by FSHB genotype. SC numbers are also not significantly different between FSHB genotypes for the OA patient group and between NOA and OA groups. SCWL in the NOA patient cohort is significantly reduced when compared to the OA control patients; however, in neither group an effect of the genotype could be observed. The cluster analysis of the whole study cohort yielded two groups only, namely NOA and OA, and no clustering according to the FSHB genotype.

DISCUSSION AND CONCLUSION

The FSHB c.-211G>T polymorphism does not affect SC numbers or SCWL, thereby in principle maintaining the spermatogenic potential. The previously observed clinical phenotype for the FSHB genotype might therefore be caused by a hypo-stimulated spermatogenesis and not due to a decreased SC number.

The effects of follicle-stimulating hormone receptor (FSHR) -29 and Ser680Asn polymorphisms in IVF/ICSI

Background The aim of this study was to analyze two different polymorphisms, Ser680Asn and -29 (G>A) promoter polymorphism, of the follicle-stimulating hormone receptor (FSHR) gene, individually but also in combination, in a sample of Greek women undergoing in vitro fertilization (IVF) or intracytoplasmic sperm injection (ICSI). Materials and methods One hundred and forty-one women undergoing IVF or ICSI and 94 controls were genotyped by real-time polymerase chain reaction (RT-PCR) for the two FSHR polymorphisms. The association of the alleles with the clinical, biochemical and other parameters concerning the controlled ovarian stimulation (COS) protocol and outcome was investigated, as well as the pregnancy rate. Results The study of each polymorphism individually revealed a positive correlation of the SerSer genotype (Ser680Asn polymorphism) with higher luteinizing hormone (LH) levels on the third day of the menstrual cycle. On the other hand, the A allele for the -29 (G>A) promoter polymorphism correlated with the increased number and quality of cumulus-oocyte complexes (COCs). No differences were detected when the different genotypes of the two polymorphisms were combined - the population study was grouped according to the number of polymorphic alleles they carried (0-4 alleles). Women who presented all polymorphic alleles, AsnAsn/AA, exhibited the lowest LH levels (2.62 ± 0.68 mIU/L), but were rarely detected (n = 2, 1.4% of the studied population). Conclusions The data from this study reflect that the investigation of the combination of polymorphisms, such as FSHR -29 and Ser680Asn, could offer a valuable tool in order to evaluate and anticipate the outcome of the ovulation induction protocols, especially in the group of patients with failed attempts.

THE FREQUENCY OF FOLLICLE-STIMULATING HORMONE RECEPTOR 2039A>G GENE POLYMORPHISM AND THE RISK OF MALE INFERTILITY IN ALBANIAN POPULATION

The purpose of this study was to determine the prevalence of allele and genotype variants of the follicle-stimulating hormone receptor (FSHR) gene polymorphic region at position Asn680Ser in the Albanian male population and associate them with the clinical parameters of infertility. The study included 114 infertile men (mean age 35.04±5.85 years) stratified according to the level of spermatogenetic impairment (oligoasthenozoospermia, asthenozoospermia and normospermia) and 112 fertile men (mean age 36.44±7.05 years) with normal semen parameters. Genotyping of the FSHR gene at position 680 was performed by TaqMan genotyping assay. All the participants underwent semen analysis, and serum reproductive hormones (FSH, luteinizing hormone, prolactin and testosterone) were also measured. The FSHR Asn680Ser genotype frequencies were as follows: Asn/Ser 42%, Ser/Ser 33.9% and Asn/Asn 24.1% in the control group, and Asn/Ser 56.1%, Ser/Ser 22.8% and Asn/Asn 21.1% in the whole group of infertile men (χ2-test: P=0.08). There was no statistically significant correlation between serum hormone levels and semen characteristics or between fertility status and FSHR Asn680Ser gene variants in the control group and the group of infertile men. However, adjusted logistic regression analysis (age, body mass index, smoking and alcohol as covariates) revealed increased odds ratio for male infertility among heterozygous Asn/Ser genotype carriers associated with lower values of semen parameters (normal morphology, concentration, total sperm count and motility). In conclusion, our case-control study further confirmed previous reports on no significant association between the FSHR Asn680Ser polymorphisms and male infertility. Nevertheless, the data presented herein indicate that the Asn/Ser genotype may increase the risk of male infertility in Albanian population.

Genetic Basis of Polycystic Ovary Syndrome (PCOS): Current Perspectives

Polycystic ovary syndrome (PCOS) is a common infertility disorder affecting a significant proportion of the global population. It is the main cause of anovulatory infertility in women and is the most common endocrinopathy affecting reproductive-aged women, with a prevalence of 8-13% depending on the criteria used and population studied. The disease is multifactorial and complex and, therefore, often difficult to diagnose due to overlapping symptoms. Multiple etiological factors have been implicated in PCOS. Due to the complex pathophysiology involving multiple pathways and proteins, single genetic diagnostic tests cannot be determined. Progress has been achieved in the management and diagnosis of PCOS; however, not much is known about the molecular players and signaling pathways underlying it. Conclusively PCOS is a polygenic and multifactorial syndromic disorder. Many genes have been associated with PCOS, which affect fertility either directly or indirectly. However, studies conducted on PCOS patients from multiple families failed to find a fully penetrant variant(s). The present study was designed to review the current genetic understanding of the disease. In the present review, we have discussed the clinical spectrum, the genetics, and the variants identified as being associated with PCOS. The mechanisms by which variants in the genes confer risk to PCOS and the nature of the physical and genetic interaction between the genetic elements underlying PCOS remain to be determined. Elucidation of genetic players and cellular pathways underlying PCOS will certainly increase our understanding of the pathophysiology of this syndrome. The study also discusses the current status of the treatment modalities for PCOS, which is important to find new ways of treatment.

Integrated structural modeling and super-resolution imaging resolve GPCR oligomers

Formation of G protein-coupled receptors (GPCRs) dimers and higher order oligomers represents a key mechanism in pleiotropic signaling, yet how individual protomers function within oligomers remains poorly understood. For the Class A/rhodopsin subfamily of glycoprotein hormone receptors (GpHRs), di/oligomerization has been demonstrated to play a significant role in regulating its signaling activity at a cellular and physiological level and even pathophysiologically. Here we will describe and discuss the developments in our understanding of GPCR oligomerization, in both health and disease, from the study of this unique and complex subfamily of GPCRs with light on the luteinizing hormone receptor (LHR). Focus will be put on the results of an approach relying on the combination of atomistic modeling by protein-protein docking with super-resolution imaging. The latter could resolve single LHR molecules to ~8nm resolution in functional asymmetric dimers and oligomers, using dual-color photoactivatable dyes and localization microscopy (PD-PALM). Structural modeling of functionally asymmetric LHR trimers and tetramers strongly aligned with PD-PALM-imaged spatial arrangements, identifying multiple possible helix interfaces mediating inter-protomer associations. Diverse spatial and structural assemblies mediating GPCR oligomerization may acutely fine-tune the cellular signaling profile.

Genetics of human female infertility†

About 10% of women of reproductive age are unable to conceive or carry a pregnancy to term. Female factors alone account for at least 35% of all infertility cases and comprise a wide range of causes affecting ovarian development, maturation of oocytes, and fertilization competence, as well as the potential of a fertilized egg for preimplantation development, implantation, and fetal growth. Genetic abnormalities leading to infertility in females comprise large chromosome abnormalities, submicroscopic chromosome deletion and duplications, and DNA sequence variations in the genes that control numerous biological processes implicated in oogenesis, maintenance of ovarian reserve, hormonal signaling, and anatomical and functional development of female reproductive organs. Despite the great number of genes implicated in reproductive physiology by the study of animal models, only a subset of these genes is associated with human infertility. In this review, we mainly focus on genetic alterations identified in humans and summarize recent knowledge on the molecular pathways of oocyte development and maturation, the crucial role of maternal-effect factors during embryogenesis, and genetic conditions associated with ovarian dysgenesis, primary ovarian insufficiency, early embryonic lethality, and infertility.

Sequence variants in FSHR and CYP19A1 genes and the ovarian response to controlled ovarian stimulation

OBJECTIVE

To examine whether sequence variants within the FSHR and CYP19A1 genes are related to the ovarian response to controlled ovarian stimulation (COS).

DESIGN

Genetic association study using both single-gene and combined analyses of women with sequence variants undergoing in vitro fertilization treatment.

SETTING

Academic research institute hospital.

PATIENT(S)

Seven hundred and five women undergoing ovarian stimulation with recombinant follicle-stimulating hormone (FSH).

INTERVENTION(S)

Peripheral blood extraction, DNA purification, and FSHR c.919G>A (rs6165, p.Thr307Ala) and CYP19A1 c.*19C>T (rs10046) sequence variants analyses.

MAIN OUTCOME MEASURE(S)

Single-gene statistical analysis and combined statistical analysis with the SPSS17.0 software; FSHR c.919G>A and CYP19A1 c.*19C>T sequence variant genotypes and clinical parameters related to the COS response as oocyte retrieval and hormone levels, doses of exogenous FSH.

RESULT(S)

Women with genotype Ala/Ala at FSHR position 307 had higher basal levels of FSH and were more likely to have a low ovarian response compared with other genotypes. Women with genotype TT at CYP19A1 yielded fewer oocytes after ovarian stimulation. The combined analysis of these two sequence variants revealed that these two single-nucleotide variants have a synergistic effect in conferring the risk of a low ovarian response.

CONCLUSION(S)

Our results support an association of sequence variants in the genes that participate in estrogen synthesis, notably the FSHR and CYP19A1 genes, with the outcome of COS.

FSHB -211 G>T Polymorphism as Predictor for TESE Success in Patients With Unexplained Azoospermia

CONTEXT

Testicular sperm extraction (TESE) followed by assisted reproductive techniques often remains the only therapeutic option for men with azoospermia due to spermatogenic failure. Reproductive parameters, such as gonadotropin levels and testicular volume or histopathology, contribute to the prediction of sperm retrieval rate (SRR) in TESE. However, there is an eminent lack of noninvasive predictive factors for TESE outcome.

OBJECTIVE

To clarify the impact of three common genetic variants affecting FSH and its cognate receptor on testicular histopathology patterns and SRR in TESE.

DESIGN

We evaluated the association of the single-nucleotide polymorphisms (SNP) FSHB -211G>T (rs10835638), FSHR -29G>A (rs1394205), and FSHR c.2039A>G (rs6166) with testicular histopathology and SRR in patients with azoospermia.

SETTING

Tertiary referral center for andrology.

PATIENTS OR OTHER PARTICIPANTS

Men (n = 1075) with azoospermia who underwent TESE (grouped by clinical pathologies).

INTERVENTION(S)

All participants underwent TESE.

MAIN OUTCOME MEASURE(S)

Testicular histopathology, SRR, and reproductive hormone levels.

RESULTS

FSHB -211G>T was significantly associated with reduced chances of sperm retrieval in patients with unexplained azoospermia. Indicating an additional mechanism, the association of the SNP with SSR could not be solely attributed to decreased FSH levels.

CONCLUSION

A common genetic factor was significantly associated with SRR in TESE. In perspective, a calculator or score including the noninvasive parameters FSH level, testicular volume, and FSHB haplotype should be considered to estimate the chances for sperm retrieval in men with azoospermia.

The relationship between FSH receptor polymorphism status and IVF cycle outcome: a retrospective observational study

RESEARCH QUESTION

What is the association between FSH receptor (FSHR) gene polymorphism at position 680 and live birth in women undergoing IVF and intracytoplasmic sperm injection (ICSI).

DESIGN

In this retrospective cohort study, data were collected from the Electronic Patient Database of the VU University Medical Centre, Amsterdam, The Netherlands. Women undergoing their first IVF/ICSI cycle between January 2008 and March 2012, of whom the FSHR genotype was determined, were included. The main outcome was live birth rate. Secondary outcomes were ongoing pregnancy, total number of follicles, oocytes and embryos.

RESULTS

The FSHR genotype distribution was as follows: 334 women in the Asn/Asn group (28.2%), 617 in the Asn/Ser group (52.1%) and 234 in the Ser/Ser group (19.7%). Basal FSH concentration was highest in the Ser/Ser group (P = 0.006). The number of oocytes (P = 0.01) and number of embryos (P = 0.02) were lowest in the Ser/Ser group. The Asn/Asn group showed a significantly lower live birth rate. Live birth rates were 21.9% versus 31.1% and 27.6% (P = 0.009), for Asn/Asn, Asn/Ser and Ser/Ser, respectively. Logistic regression analysis, however, showed no significant difference on cumulative live birth rate between the three genotypes either unadjusted or when adjusted for age.

CONCLUSION

The homozygous Ser/Ser genotype of FSHR polymorphism at position 680 is associated with a reduced ovarian response to ovarian stimulation in IVF/ICSI. No difference in cumulative live birth rate was found.

Pharmacogenetics of FSH Action in the Male

Male infertility is a major contributor to couple infertility, however in most cases it remains "idiopathic" and putative treatment regimens are lacking. This leads to a scenario in which intra-cytoplasmic spermatozoa injection (ICSI) is widely used in idiopathic male infertility, though the treatment burden is high for the couple and it entails considerable costs and risks. Given the crucial role of the Follicle-stimulating hormone (FSH) for spermatogenesis, FSH has been used empirically to improve semen parameters, but the response to FSH varied strongly among treated infertile men. Single nucleotide polymorphisms (SNPs) within FSH ligand/receptor genes (FSHB/FSHR), significantly influencing reproductive parameters in men, represent promising candidates to serve as pharmacogenetic markers to improve prediction of response to FSH. Consequently, several FSH-based pharmacogenetic studies have been conducted within the last years with unfortunately wide divergence concerning selection criteria, treatment and primary endpoints. In this review we therefore outline the current knowledge on single nucleotide polymorphisms (SNPs) in the FSH and FSH receptor genes and their putative functional effects. We compile and critically assess the previously performed pharmacogenetic studies in the male and propose a putative strategy that might allow identifying patients who could benefit from FSH treatment.

Effects of a Polymorphism in the Promoter Region of the Follicle-Stimulating Hormone Subunit Beta (FSHB) Gene on Female Reproductive Outcomes

BACKGROUND

Follicle-stimulating hormone (FSH) is essential to the hypothalamic-pituitary-gonadal axis, playing a key role in human reproduction. It is a heterodimer comprised of a hormone-specific β-chain (FSH-β) that is associated with an α-chain. It exerts its biological activities by binding to the FSH receptor (FSHR). The β-subunit, which is encoded by the FSHB gene, is responsible for ensuring binding specificity to the FSHR. There is a promoter polymorphism in this gene, c.-211G>T (rs10835638), upstream of the transcription start site; and in vitro studies have reported that the T allele decreases FSHB transcription in gonadotrophic cells.

AIMS

Investigate the possible effects of the FSHB c.-211G/T polymorphism on hormonal profile and in in vitro fertilization (IVF)/intracytoplasmic sperm injection outcomes in normoovulatory Brazilian women.

METHODS

A cross-sectional study of 140 women (median age = 33 years [CI: 32-34]) with infertility mainly caused by male (n = 85) or tuboperitoneal (n = 55) factors. In this study we evaluated FSH, estradiol, luteinizing hormone (LH), progesterone, prolactin and anti-Mullerian hormone levels, and antral follicle counting (AFC). Genotyping was performed using the TaqMan real-time polymerase chain reaction methodology.

RESULTS

The wild-type allele G was found in 86.4% and the polymorphic allele T in 13.6% of the women respectively. The TT genotype was not found in any women. Women carrying the GT genotype had a poorer response more frequently to controlled ovarian hyperstimulation when compared to individuals with the GG genotype (47.4% vs. 26.5%, p = 0.010), higher LH levels (3.1 IU/mL vs. 2.4 IU/mL, p = <0.001), lower AFC (8.0 vs. 10.0, p = 0.03), oocytes retrieved (3.0 vs. 5.0, p = 0.03), MII (3.0 vs. 4.0, p = 0.02), and embryos (2.0 vs. 3.0, p = 0.02). Despite these findings, no difference was observed in pregnancy rate.

CONCLUSION

Our findings suggest that the FSHB c.-211G/T polymorphism may modestly alter some aspects of the female reproductive system, but they are not associated with significantly different IVF outcomes.

Frequency of the T307A, N680S, and -29G>A single-nucleotide polymorphisms in the follicle-stimulating hormone receptor in Mexican subjects of Hispanic ancestry

BACKGROUND

FSHR SNPs may influence the ovarian sensitivity to endogenous and exogenous FSH stimulation. Given the paucity of data on the FSHR c.919A > G, c.2039A > G and - 29G > A SNPs in Hispanic population, we here analyzed their frequency distribution in Mexican mestizo women.

METHODS

Samples from 224 Mexican mestizo women enrolled in an IVF program as well as a genotype database from 8182 Mexican mestizo subjects, were analyzed for FSHR SNPs at positions c.919, c.2039 and - 29G > A. Association between the genetic variants and reproductive outcomes was assessed.

RESULTS

The c.919 and c.2039 SNPs were in strong linkage disequilibrium and their corresponding genotype frequencies in the IVF group were: AA 46.8%, AG 44.2%, and GG 8.9%, and AA 41.9%, AG 48.2% and GG 9.8%, respectively. For the -29G > A SNP, genotype frequencies were 27% (GG), 50% (GA) and 23% (AA). In normal oocyte donors with the c.2039 GG genotype, the number of oocytes recovered after ovarian stimulation (COS) were significantly (p < 0.01) lower than in those bearing other genotypes in this or the -29G > A SNP. Analysis of the large scale database revealed that both allelic and genotype frequencies for the three SNPs were very similar to those detected in the IVF cohort (p ≥ 0.38) and that female carriers of the c.2039 G allele tended to present lower number of pregnancies than women bearing the AA genotype; this trend was stronger when women with more Native American ancestry was separately analyzed (OR = 2.0, C.I. 95% 1.03-3.90, p = 0.04). There were no differences or trends in the number of pregnancies among the different genotypes of the -29G > A SNP.

CONCLUSIONS

The frequency of the GG/GG combination genotype for the c.919 and c.2039 SNPs in Mexican hispanics is among the lowest reported. The GG genotype is associated with decreased number of oocytes recovered in response to COS as well as to lower pregnancy rates in Hispanic women from the general population. The absence of any effect of the -29AA genotype on the response to COS, indicates that there is no need to perform this particular genotype testing in Hispanic women with the purpose of providing an individually-tailored COS protocol.

Pituitary Diseases and Bone

Neuroendocrinology of bone is a new area of research based on the evidence that pituitary hormones may directly modulate bone remodeling and metabolism. Skeletal fragility associated with high risk of fractures is a common complication of several pituitary diseases such as hypopituitarism, Cushing disease, acromegaly, and hyperprolactinemia. As in other forms of secondary osteoporosis, pituitary diseases generally affect bone quality more than bone quantity, and fractures may occur even in the presence of normal or low-normal bone mineral density as measured by dual-energy X-ray absorptiometry, making difficult the prediction of fractures in these clinical settings. Treatment of pituitary hormone excess and deficiency generally improves skeletal health, although some patients remain at high risk of fractures, and treatment with bone-active drugs may become mandatory. The aim of this review is to discuss the physiological, pathophysiological, and clinical insights of bone involvement in pituitary diseases.

Pharmacogenetic algorithm for individualized controlled ovarian stimulation in assisted reproductive technology cycles

Controlled ovarian stimulation (COS) is crucial for optimizing in-vitro fertilization (IVF)/intracytoplasmic sperm injection (ICSI) success. Multiple factors influence the ovarian response to COS, making predictions about oocyte yields not so straightforward. As a result, the ovarian response may be poor or suboptimal, or even excessive, all of which have negative consequences for the affected patient. There is a group of patients that present with a suboptimal response to COS despite normal biomarkers of ovarian reserve, such as AFC and AMH. These patients have a lower number of retrieved oocytes than what was expected based on their ovarian reserve, thus showing the inadequacy of using only the traditional ovarian reserve biomarkers to predict the ovarian response. Suboptimal response to COS might be related to ovarian sensitivity to exogenous gonadotropins modulated by genetic factors. The understanding of the gene polymorphisms related to reproductive function can help to improve the clinical management of this patient population and to explain some of the individual patient variability in response to COS. The development of a pharmacogenetic approach concerning COS in the context of assisted reproduction seems attractive as it might help to understand the relationship between genetic variants and ovarian response to exogenous gonadotropins. The patient's genetic profile could be used to select the most appropriate gonadotropin type, predict the optimal dosage for each drug, develop a cost-effective treatment plan, maximize the success rates, and lastly, decrease the time-to-pregnancy.

The Impact of FSHR Gene Polymorphisms Ala307Thr and Asn680Ser in the Endometriosis Development

Endometriosis is an estrogen-dependent inflammatory disease that affects a large number of women in reproductive age. Follicle-stimulating hormone (FSH) plays a role in steroidogenesis and acts through a transmembrane glycoprotein, FSH receptor (FSHR). Polymorphisms in FSHR gene were previously associated with variability in FSH serum level and reproductive outcomes, but its relation with endometriosis has not been clarified and demonstrated conflicting results, ranging from strong links to no association to endometriosis. Inspired by these findings, we aimed to investigate the influence of FSHR Ala307Thr and Asn680Ser polymorphisms in the risk of endometriosis development and/or progression and the status of fertility in 352 women with endometriosis and 510 fertile controls. Single-marker analysis revealed no significant difference for both Ala307Thr and Asn680Ser polymorphisms between overall endometriosis and control group. However, when the endometriosis group was subdivided according to fertility status and disease stage, a positive association was found between 680Ser/Ser or GG genotype of the Asn680Ser polymorphism and fertile women with endometriosis (p = 0.004). Combined alleles of FSHR polymorphisms revealed that "GG/307Ala680Ser" was more frequently found in fertile women with endometriosis (haplotype frequency of 45.4% in fertile women with endometriosis and 38.3% in controls, p = 0.041). The combined alleles of FSHR polymorphisms disclosed that "GG/307Ala680Ser" was more frequently found in fertile women with endometriosis (haplotype frequency of 45.4% in fertile women with endometriosis and 38.3% in controls, p = 0.049), while "GA/307Ala680Asn" haplotype was less frequently found in endometriosis group (haplotype frequency of 6.5% in cases and 11.9% in controls, p = < 0.001), regardless of fertility status and stage of the disease. The findings suggest that 680Ser-Ser/GG genotype and "GG/307Ala680Ser" haplotype increase the risk of endometriosis in fertile women, while "GA/307Ala680Asn" haplotype decreases the risk of endometriosis development and progression.

Understanding Ovarian Hypo-Response to Exogenous Gonadotropin in Ovarian Stimulation and Its New Proposed Marker-The Follicle-To-Oocyte (FOI) Index

Hypo-responsiveness to controlled ovarian stimulation is an undervalued topic in reproductive medicine. This phenomenon manifests as a low follicles output rate (FORT) with a discrepancy between the relatively low number of pre-ovulatory follicles which develop following ovarian stimulation as compared to the number of antral follicles available at the start of stimulation. The pathophysiology mechanisms explaining the ovarian resistance to gonadotropin stimulation are not fully understood, but the fact that both hypo-responders and normal responders share similar phenotypic characteristics suggests a genotype-based mechanism. Indeed, existing evidence supports the association between specific gonadotropin and their receptor polymorphisms and ovarian hypo-response. Apart from genotypic trait, environmental contaminants and oxidative stress might also be involved in the hypo-response pathogenesis. The ratio between the number of oocytes collected at the ovum pick up and the number of antral follicles at the beginning of OS [Follicle to oocyte index (FOI)] is proposed as a novel parameter to assess the hypo-response. Compared with traditional ovarian reserve markers, FOI might reflect most optimally the dynamic nature of follicular growth in response to exogenous gonadotropin. In this review, we contextualize the role of FOI as a parameter to identify this condition, discuss the underlying mechanisms potentially implicated in the pathogenesis of hypo-response, and appraise possible the treatment strategies to overcome hyper-responsiveness to gonadotropin stimulation.

Association of follicle-stimulating hormone receptor single nucleotide polymorphisms with fertility in Greek men

BACKGROUND AND OBJECTIVE

Although several epidemiological studies have been conducted, the impact of follicle-stimulating hormone receptor (FSHR) polymorphisms on male infertility remains unclear. The aim of this study was to investigate the prevalence of specific FSHR single nucleotide polymorphisms (SNPs) in the Greek population and associate the latter with the clinical phenotype.

PATIENTS AND METHODS

We enrolled 96 subjects: men with idiopathic non-obstructive azoospermia (n = 78) were compared with a control group of fertile men (n = 18) for SNPs in FSHR positions c.-29, c.566, c.919, and c.2039. The SNP in position 566 (c.566C > T) was assessed by polymerase chain reaction restriction fragment length polymorphism (PCR-RFLP) and the other three SNPs (c.-29G > A, c.919A > G, c.2039A > G) with single-strand conformation polymorphism (SSCP); all of them were validated with DNA sequence.

RESULTS

No polymorphisms were detected in positions c.-29 and c.919 (c.-29G > A, c.919A > G). The heterozygous SNP (AG) at position 2039 was associated with different size of the right testis (p = 0.008). There was no association between the c.566C > T SNPs polymorphism and hormonal or semen parameters. The combination SNP 2039 AA with 566 CT revealed significant association with FSH and LH concentrations.

CONCLUSIONS

FSHR SNPs at positions c.-29, c.566, c.919, and c.2039 (c.-29G > A, c.566C > T, c.919A > G, c.2039A > G) do not appear to play specific roles in male infertility. Larger studies are needed to confirm these results.

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.

Altered micro-ribonucleic acid expression profiles of extracellular microvesicles in the seminal plasma of patients with oligoasthenozoospermia

OBJECTIVE

To determine whether microRNA (miRNA) expression profile is different in extracellular microvesicles collected from seminal plasma of men with oligoasthenozoospermia, to gain further insight into molecular mechanisms underlying male infertility.

DESIGN

Microarray with quantitative real-time polymerase chain reaction validation and Western blot analysis confirmation.

SETTING

University research and clinical institutes.

PATIENT(S)

A total of 24 men, including 12 oligoasthenozoospermic subfertile men and 12 normozoospermic men.

INTERVENTION(S)

None.

MAIN OUTCOME MEASURE(S)

Statistically significant altered miRNA expression profiles in oligoasthenozoospermic subfertile men compared with normozoospermic fertile men.

RESULT(S)

Extracellular microvesicles including exosomes were isolated from seminal plasma by ultracentrifugation. Presence of exosome-specific proteins was confirmed by Western blotting. In the extracellular microvesicles, we analyzed 1,205 miRNAs by microarray and identified 36 miRNAs with altered expression levels in oligoasthenozoospermic compared with normozoospermic fertile men. Seven miRNAs were overexpressed and 29 miRNAs were underexpressed in oligoasthenozoospermic men. Using quantitative real-time polymerase chain reaction as an independent method, we confirmed the significantly higher expression levels of miR-765 and miR-1275 and the significantly lower expression level of miR-15a in oligoasthenozoospermic subfertile men as compared with the normozoospermic men.

CONCLUSION(S)

We identified altered expression levels of miRNAs in extracellular microvesicles from seminal plasma as part of the molecular events in the male genital tract. These miRNAs may help to understand the molecular mechanisms underlying male infertility.

Genetic variations altering FSH action affect circulating hormone levels as well as follicle growth in healthy peripubertal girls

STUDY QUESTION

Do variants of the genes encoding follicle stimulating hormone (FSH) beta subunit (B) and FSH receptor (R) impact circulating reproductive hormone levels and ovarian follicle maturation in healthy peripubertal girls?

SUMMARY ANSWER

FSHB and FSHR genetic variants exert, alone or their combination, distinct effects on reproductive hormone levels as well as ovarian follicle maturation in healthy peripubertal girls.

WHAT IS KNOWN ALREADY

FSHB and FSHR genetic variants impact reproductive hormone levels as well as associated pathologies in women. While FSHR c. 2039A>G is known to alter gonadotrophin levels in women, FSHR c.-29G>A has not yet been shown to exert effect and there are conflicting results concerning FSHB c.-211G>T.

STUDY DESIGN, SIZE, DURATION

This population-based study included 633 girls recruited as part of two cohorts, the COPENHAGEN Puberty Study (2006-2014, a cross-sectional and ongoing longitudinal study) and the Copenhagen Mother-Child Cohort (1997-2002, including transabdominal ultrasound (TAUS) of the ovaries in a subset of 91 peripubertal girls).

PARTICIPANTS/MATERIALS, SETTING, METHODS

Clinical examinations, including pubertal breast stage (Tanner's classification B1-B5) were performed. Circulating levels of FSH, luteinizing hormone (LH), estradiol, anti-Mullerian hormone (AMH) and inhibin-B were assessed by immunoassays. In a subset of the girls (n = 91), ovarian volume and the number/size of antral follicles were assessed by TAUS. Genotypes were determined by competitive PCR.

MAIN RESULTS AND THE ROLE OF CHANCE

FSHR c.2039A>G minor alleles were positively associated with serum FSH (β = 0.08, P = 0.004), LH (β = 0.06, P = 0.012) and estradiol (β = 0.06, P = 0.017) (adjusted for Tanner stages). In a combined model, FSHR c.-29G>A and FSHR c.2039A>G alleles were positively associated with FSH levels in early-pubertal girls (B2 + B3, n = 327, r = 0.1, P = 0.02) and in young adolescents (B4 + B5, n = 149, r = 0.2, P = 0.01). Serum AMH and inhibin B levels were not significantly influenced by the single nucleotide polymorphisms (SNPs). Single SNPs were not associated with follicles counts, however, a cumulative minor allele count (FSHB c.-211 G>T and FSHR c.-29G>A) was negatively associated with the number of large follicles (≥5 mm) (n = 91, P = 0.04) (adjusted for Tanner stages).

LIMITATIONS, REASONS FOR CAUTION

Since we studied girls and young adolescents during pubertal transition, our study may not be fully comparable with previous studies on FSHB and FSHR variants in adult women. The group of young adolescents (Tanner B4 + B5) reflects the endocrine situation in adult women best, however, the group is not large enough to contribute substantially to the conflicting results concerning the influence of FSHB c.-211G>T in adult women. Furthermore, we have no information about the exact day of the menstrual cycle in the subgroup of girls with menarche.

WIDER IMPLICATIONS OF THE FINDINGS

The sex-specific interaction of FSHB and FSHR genetic variants and physiological as well as pathological conditions is being increasingly elucidated. The variant triplet set might serve as diagnostic and pharmacogenetic marker. For the first time, we show an additional effect of FSHR c.-29G>A on serum FSH levels in healthy girls. Moreover, morphological data suggest impaired FSH-induced maturation of ovarian follicles in minor allele carriers of FSHB c.-211G>T and FSHR c.-29G>A. This may explain previous findings of delayed pubertal onset in these girls.

STUDY FUNDING/COMPETING INTERESTS

Funding was provided by the Danish Agency for Science, Technology and Innovation (09-067180), Danish Ministry of the Environment, CeHoS (MST-621-00065), Capital Region of Denmark (December 2011), Ministry of Higher Education and Science (DFF-1331-00113) and EDMaRC (Danish Ministry of Health). A.S.B. was funded from December 2015 by ReproUnion (EU Interreg Öresund-Kattegat-Skagerrak). The authors declare no conflict of interest.

Combined assessment of polymorphisms in the LHCGR and FSHR genes predict chance of pregnancy after in vitro fertilization

STUDY QUESTION

Can gonadotrophin receptor variants separately or in combination, be used for the prediction of pregnancy chances in in vitro fertilization (IVF) trials?

SUMMARY ANSWER

The luteinizing hormone/human chorionic gonadotrophin receptor (LHCGR) variant N312S and the follicle-stimulating hormone receptor (FSHR) variant N680S can be utilized for the prediction of pregnancy chances in women undergoing IVF.

WHAT IS KNOWN ALREADY

The FSHR N680S polymorphism has been shown to affect the ovarian response in response to gonadotrophin treatment, while no information is currently available regarding variants of the LHCGR in this context.

STUDY DESIGN, SIZE, DURATION

Cross-sectional study, duration from September 2010 to February 2015. Women undergoing IVF were consecutively enrolled and genetic variants compared between those who became pregnant and those who did not. The study was subsequently replicated in an independent sample. Granulosa cells from a subset of women were investigated regarding functionality of the genetic variants.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Women undergoing IVF (n = 384) were enrolled in the study and genotyped. Clinical variables were retrieved from medical records. For replication, an additional group of n = 233 women was utilized. Granulosa cells from n = 135 women were isolated by flow cytometry, stimulated with Follitropin alpha or Menotropin, and the downstream targets 3',5'-cyclic adenosine monophosphate (cAMP) and inositol 1,4,5-trisphosphate (IP3) measured with enzyme-linked immunosorbent assay.

MAIN RESULTS AND THE ROLE OF CHANCE

Women homozygous for serine (S) in both polymorphisms displayed higher pregnancy rates than women homozygous asparagine (N) (OR = 14.4, 95% CI: [1.65, 126], P = 0.016). Higher pregnancy rates were also evident for women carrying LHCGR S312, regardless of FSHR variant (OR = 1.61, 95% CI: [1.13, 2.29], P = 0.008). These women required higher doses of FSH for follicle recruitment than women homozygous N (161 versus 148 IU, P = 0.030). When combining the study cohort with the replication cohort (n = 606), even stronger associations with pregnancy rates were noted for the combined genotypes (OR = 11.5, 95% CI: [1.86, 71.0], P = 0.009) and for women carrying LHCGR S312 (OR = 1.49, 95% CI: [1.14, 1.96], P = 0.004). A linear significant trend with pregnancy rate and increasing number of G alleles was also evident in the merged study population (OR = 1.34, 95% CI: [1.10, 1.64], P = 0.004). A lower cAMP response in granulosa cells was noted following Follitropin alpha stimulation for women homozygous N in both polymorphisms, compared with women with other genotypes (0.901 pmol cAMP/mg total protein versus 2.19 pmol cAMP/mg total protein, P = 0.035).

LIMITATIONS, REASONS FOR CAUTION

Due to racial differences in LHCGR genotype distribution, these results may not be applicable for all populations.

WIDER IMPLICATIONS OF THE FINDINGS

Despite that >250 000 cycles of gonadotrophin stimulations are performed annually worldwide prior to IVF, it has not been possible to predict neither the pregnancy outcome, nor the response to the hormone with accuracy. If LHCGR and FSHR variants are recognized as biomarkers for chance of pregnancy, more individualized and thereby more efficient treatment modalities can be developed.

STUDY FUNDING, COMPETING INTERESTS

This work was supported by Interreg IV A, EU (grant 167158) and ALF governments grant (F2014/354). Merck-Serono (Darmstadt, Germany) supported the enrollment of the subjects. The authors declare no conflict of interest.

The role of reproductive hormones in epithelial ovarian carcinogenesis

Epithelial ovarian cancer comprises ∼85% of all ovarian cancer cases. Despite acceptance regarding the influence of reproductive hormones on ovarian cancer risk and considerable advances in the understanding of epithelial ovarian carcinogenesis on a molecular level, complete understanding of the biologic processes underlying malignant transformation of ovarian surface epithelium is lacking. Various hypotheses have been proposed over the past several decades to explain the etiology of the disease. The role of reproductive hormones in epithelial ovarian carcinogenesis remains a key topic of research. Primary questions in the field of ovarian cancer biology center on its developmental cell of origin, the positive and negative effects of each class of hormones on ovarian cancer initiation and progression, and the role of the immune system in the ovarian cancer microenvironment. The development of the female reproductive tract is dictated by the hormonal milieu during embryogenesis. Intensive research efforts have revealed that ovarian cancer is a heterogenous disease that may develop from multiple extra-ovarian tissues, including both Müllerian (fallopian tubes, endometrium) and non-Müllerian structures (gastrointestinal tissue), contributing to its heterogeneity and distinct histologic subtypes. The mechanism underlying ovarian localization, however, remains unclear. Here, we discuss the role of reproductive hormones in influencing the immune system and tipping the balance against or in favor of developing ovarian cancer. We comment on animal models that are critical for experimentally validating existing hypotheses in key areas of endocrine research and useful for preclinical drug development. Finally, we address emerging therapeutic trends directed against ovarian cancer.

LH (Trp8Arg/Ile15Thr), LHR (insLQ) and FSHR (Asn680Ser) polymorphisms genotypic prevalence in women with endometriosis and infertility

PURPOSE

To verify if polymorphisms of LH (Trp8Arg/Ile15Thr), LH receptor (insLQ), and FSH receptor (Asn680Ser) are associated with endometriosis and infertility.

METHODS

This is a prospective case-control study. Sixty-seven patients with endometriosis and infertility (study group) and 65 healthy fertile patients (control group) were enrolled in the study between July 2010 and July 2013. All patients had their endometriosis diagnosis made or excluded by laparoscopic surgery; study group was submitted to the surgery for infertility investigation and control group for tubal ligation. Day-3 serum hormones were collected from all patients. Analysis of nucleotide mutations for LH polymorphisms (Trp8Arg and Ile15Thr), LHR polymorphism (insLQ), and FSHR polymorphism (Asn680Ser) were performed by PCR.

RESULTS

Day-3 FSH, estradiol and LH serum levels were not different between the groups, while CA-125 was higher in patients with endometriosis and infertility. All polymorphisms studied were in Hardy-Weinberg equilibrium. The prevalence of insLQ was significantly higher in patients with endometriosis and infertility (P = 0.005). Allele occurrence in control group was 0.10 versus 0.25 in infertile endometriosis group (P = 0.001). There was no difference regarding Trp8Arg/Ile15Thr (P > 0.05) and Asn680Ser (P > 0.05) prevalence between groups.

CONCLUSION

This is the first time that prevalence of insLQ was shown to be higher in patients with endometriosis and infertility than in healthy fertile patients. There was no difference in LH and FSHR polymorphisms' prevalence between groups.

Genotyping common FSHR polymorphisms based on competitive amplification of differentially melting amplicons (CADMA)

PURPOSE

To provide an improved platform for simple, reliable, and cost-effective genotyping.

BACKGROUND

Modern fertility treatments are becoming increasingly individualized in an attempt to optimise the follicular response and reproductive outcome, following controlled ovarian stimulation. As the field of pharmacogenetics evolve, genetic biomarkers such as polymorphisms of the follicle stimulating hormone receptor (FSHR) may be included as a predictive tool for individualized fertility treatment. However, the currently available genotyping methods are expensive, time-consuming or have a limited analytical sensitivity. Here, we present a novel version of "competitive amplification of differentially melting amplicons" (CADMA), providing an improved platform for simple, reliable, and cost-effective genotyping.

METHODS

Two CADMA based assays were designed for the two common polymorphisms of the FSHR gene: rs6165 (c.919A > G, p. Thr307Ala, FSHR 307) and rs6166 (c.2039A > G, p. Asn680Ser, FSHR 680). To evaluate the reliability of the new CADMA-based assays, the genotyping results were compared with two conventional PCR based genotyping methods; allele-specific PCR (AS-PCR) and Sanger sequencing.

RESULTS

The genotype frequencies for both polymorphisms were 35 % (TT), 42 % (CT), and 23 % (CC), respectively. A 100 % accordance was observed between the CADMA-based genotyping results and sequencing results, whereas 5 discrepancies were observed between the AS-PCR results and the CADMA-based genotyping results. Comparing the CADMA-based assays to (AS-PCR) and Sanger sequencing, the CADMA based assays showed an improved analytical sensitivity and a wider applicability.

CONCLUSIONS

The new assays provide a reliable, fast and user-friendly genotyping method facilitating a wider implication in clinical practise.

Follicle-stimulating hormone receptor gene polymorphism in chronic anovulatory women, with or without polycystic ovary syndrome: a cross-sectional study

BACKGROUND

Polymorphisms at codons 307 and 680 are the most commonly encountered allelic variants of the follicle-stimulating hormone receptor (FSHR) gene. Studies in Caucasians suggest that certain FSHR variants are more common in women with polycystic ovary syndrome (PCOS) than normal women. The objective of this study was to determine the distribution of FSHR gene polymorphisms at codons 307 and 680 in Thai women with chronic anovulation, without (121 women) and with PCOS (133 women), using 132 known fertile women as controls.

METHODS

DNA samples from peripheral blood lymphocytes were extracted and analyzed by polymerase chain reaction-restriction fragment length polymorphism.

RESULTS

The prevalence of Threonine307Threonine (TT), Threonine307Alanine (TA), and Alanine307Alanine (AA) genotypes at codon 307 was 53.0% (95% CI = 44.2-61.7%), 42.4% (95% CI = 34-51.3%), and 4.5% (95% CI = 1.9-10.1%) in controls; 52.6% (95% CI = 43.8-61.3%), 39.8% (95% CI = 31.6-48.7%), and 7.5% (95% CI = 3.9-13.7%) in PCOS women; and 50.4% (95% CI = 42.8-61.2%), 45.4% (95% CI = 34.9-53.1%), and 4.5% (95% CI = 1.5-9.6%) in anovulatory women without PCOS, respectively. The prevalence of Asparagine680Asparagine (NN), Asparagine680Serine (NS), and Serine680Serine (SS) genotypes at codon 680 was 54.5% (95% CI = 45.7-63.2%), 40.9% (95% CI = 32.5-49.8%), and 4.5% (95% CI = 1.9-10.1%) in controls; 51.9% (95% CI = 43.1-60.6%), 44.4% (95% CI = 35.8-53.2%), and 3.8% (95% CI = 1.4-9.0%) in PCOS women; and 47.9% (95% CI = 40.4-58.8%), 47.1% (95% CI = 36.5-54.7%), and 5.0% (95% CI = 2-10.9%) in anovulatory women without PCOS, respectively. The prevalence of FSHR gene polymorphisms at both codons were not statistically different among the three groups.

CONCLUSIONS

In Thai women, there was no association between the FSHR gene polymorphism at codons 307 and 680 and chronic anovulation.

Mechanisms in endocrinology: Genetics of FSH action: a 2014-and-beyond view

OBJECTIVE

To assess the pharmacogenetic potential of FSH for infertility treatment.

DESIGN

Review of the literature and genomic databases.

METHODS

Single-nucleotide polymorphism (SNP) assessed: rs6166 (c.2039A>G, p.N680S), rs6165 (c.919A>G, p.T307A), rs1394205 (c.-29G>A) in FSHR, and rs10835638 (c.-211G>T) in FSHB. Literature search via PubMed. Blast analysis of genomic information available in the NCBI nucleotide database. Comparison of allele frequency and haplotype distribution using the http://spsmart.cesga.estool.

RESULTS

All these SNPs appear first in Homo, result in reduced FSH action, and are present with variable frequencies and combinations worldwide. Stringent clinical studies demonstrate that the FSHR genotype influences serum FSH levels and gonadal response in both sexes. Serum FSH levels depend on the -211G>T SNP, influencing transcriptional activity of the FSHB promoter. Genotypes reducing FSH action are overrepresented in infertile subjects.

CONCLUSIONS

Although the clinical relevance of the FSHR polymorphisms alone is limited, the combination of FSHR and FSHB genotypes has a much stronger impact than either one alone in both sexes. About 20% of people are carriers of the alleles associated with lower serum FSH levels/reduced FSHR expression or activity, possibly less favorable for reproduction. Prospective studies need to investigate whether stratification of infertile patients according to their FSHR-FSHB genotypes improves clinical efficacy of FSH treatment compared with the current, naïve approach. A relative enrichment of less favorable FSHR-FSHB genotypes may be related to changes in human reproductive strategies and be a marker of some health-related advantage at the cost of reduced fertility.

Gene polymorphisms in female reproduction

This chapter presents an overview of the gene polymorphisms underlying the functions of ovarian receptors and their clinical implications in the female fecundity. A selection of genetic studies revealing significant associations between receptor polymorphisms, gene mutations, and some pathological conditions (i.e., female infertility, premature ovarian failure, polycystic ovary syndrome, endometriosis) are reviewed.

Fine-mapping an association of FSHR with preterm birth in a Finnish population

Preterm birth is a complex disorder defined by gestations of less than 37 weeks. While preterm birth is estimated to have a significant genetic component, relative few genes have been associated with preterm birth. Polymorphism in one such gene, follicle-stimulating hormone receptor (FSHR), has been associated with preterm birth in Finnish and African American mothers but not other populations. To refine the genetic association of FSHR with preterm birth we conducted a fine-mapping study at the FSHR locus in a Finnish cohort. We sequenced a total of 44 kb, including protein-coding and conserved non-coding regions, in 127 preterm and 135 term mothers. Overall, we identified 288 single nucleotide variants and 65 insertion/deletions of 1-2 bp across all subjects. While no common SNPs in protein-coding regions were associated with preterm birth, including one previously associated with timing of fertilization, multiple SNPs spanning the first and second intron showed the strongest associations. Analysis of the associated SNPs revealed that they form both a protective (OR = 0.50, 95% CI = 0.25-0.93) as well as a risk (OR = 1.89, 95% CI = 1.08-3.39) haplotype with independent effects. In these haplotypes, two SNPs, rs12052281 and rs72822025, were predicted to disrupt ZEB1 and ELF3 transcription factor binding sites, respectively. Our results show that multiple haplotypes at FSHR are associated with preterm birth and we discuss the frequency and structure of these haplotypes outside of the Finnish population as a potential explanation for the absence of FSHR associations in some populations.

Expression and purification of the extracellular domain of the human follicle-stimulating hormone receptor using Escherichia coli

AIM

Although much is known about the structure and biological functions of follicle-stimulating hormone (FSH) receptor (FSHR), the interaction of FSHR and FSH has been challenging to characterize due to the limited quantity of active FSHR protein produced by simple methods. The goal of this study was to express and purify the extracellular domain (ECD) of human FSHR (hFSHR).

METHODS

Total RNA was isolated from normal human ovary tissue. cDNA for hFSHR ECD were amplified and subsequently ligated into the pET32a(+) vector. The plasmid vector construct was confirmed by polymerase chain reaction and sequencing. Expression in Escherichia coli Rosetta (DE3) pLysS strain was induced by isopropyl-thio-β-D-thiogalactoside, and the recombinant products were purified by immuno-affinity chromatography using an Ni-NTA and High-Q column. The recombinant protein was confirmed by western blotting.

RESULTS

Following induction, E. coli expressed a recombinant protein of approximately 65 kDa in size, whereas the non-induced E. coli did not express the recombinant protein. The recombinant fragments purified using a High-Q column demonstrated a single band and an abundant yield. The recombinant protein was soluble and specifically recognized by an antibody for hFSHR. Additionally, four mutation sites were detected that resulted in amino acid shifts at position 112 Asn/Thr, 197 Glu/Ala, 198 Leu/Val and 307 Ala/Thr.

CONCLUSION

The recombinant hFSHR ECD protein was expressed and purified. This method could be easily scaled for increased production and may facilitate additional applications utilizing FSHR in assisted reproductive technology, a contraceptive FSH vaccine and FSHR-targeted therapeutic agents used to treat ovarian cancer.

FSH receptor gene variants are rarely associated with premature ovarian failure

FSH receptor (FSHR) gene variants have been associated with premature ovarian failure (POF). Genomic DNA from New Zealand women with POF (n=80) and control women (n=80) was screened for variants in FSHR exons 7 and 10. FSHR exon 7 variants, including the c.566C>T Finnish founder mutation (p.Ala189Val), were not detected. Previously reported FSHR exon 10 polymorphisms were identified in both groups with similar allelic distributions. A novel heterozygous FSHR exon 10 variant c.1411A>T, p.Ile471Phe was observed in one woman with a family history of POF, but not her affected siblings. It is concluded that variants in exons 7 and 10 of FSHR are not frequently associated with the development of POF in the New Zealand population.

Follicle-stimulating hormone treatment in normogonadotropic infertile men

Several empirical treatments have been proposed to treat idiopathic infertility in men, including follicle-stimulating hormone (FSH). FSH administration is effective in patients with hypogonadotropic hypogonadism, which suggests it might be useful in patients with oligozoospermia who have normal FSH levels. Indeed, many studies have evaluated the efficacy of FSH administration in these patients, several of which have shown improvements in sperm parameters. By contrast, other studies have not reported any significant effect of FSH administration on conventional sperm parameters, although some of have reported the normalization of spermatozoon ultrastructural morphology, as well as reductions in DNA fragmentation, production of reactive oxygen species and aneuploidy. Contemporary studies suggest that the response to FSH treatment in oligozoospermic patients might, at least partially, reflect polymorphisms of the FSH receptor gene. Thus, FSH administration in oligozoospermic men with normal serum FSH levels might be efficacious only in selected patients. For this reason, additional studies are needed to determine the predictive factors and clinical conditions that can be used to identify patients who could benefit from FSH treatment.