Mutation in the follicle-stimulating hormone receptor gene causes hereditary hypergonadotropic ovarian failure

Novel NR5A1 missense mutation in premature ovarian failure: detection in han chinese indicates causation in different ethnic groups

Background

The etiology of most premature ovarian failure (POF) cases is usually elusive. Although genetic causes clearly exist and a likely susceptible region of 8q22.3 has been discovered, no predominant explanation exists for POF. More recently, evidences have indicated that mutations in NR5A1 gene could be causative for POF. We therefore screened for mutations in the NR5A1 gene in a large cohort of Chinese women with non-syndromic POF.

Methods

Mutation screening of NR5A1 gene was performed in 400 Han Chinese women with well-defined 46,XX idiopathic non-syndromic POF and 400 controls. Subsequently, functional characterization of the novel mutation identified was evaluated in vitro.

Results

A novel heterozygous missense mutation [c.13T>G (p.Tyr5Asp)] in NR5A1 was identified in 1 of 384 patients (0.26%). This mutation impaired transcriptional activation on Amh, Inhibin-a, Cyp11a1 and Cyp19a1 gene, as shown by transactivation assays. However, no dominant negative effect was observed, nor was there impact on protein expression and nuclear localization.

Conclusions

This novel mutation p.Tyr5Asp, in a novel non-domain region, is presumed to result in haploinsufficiency. Irrespectively, perturbation in NR5A1 is not a common explanation for POF in Chinese.

Epistasis between IGF2R and ADAMTS19 polymorphisms associates with premature ovarian failure

STUDY QUESTION

Do single nucleotide polymorphisms (SNPs) or synergistic interactions between SNPs and diplotypes within the insulin-like growth factor 2 receptor (IGF2R) and ADAM metallopeptidase with thrombospondin type 1 motif, 19 (ADAMTS19), contribute to premature ovarian failure (POF)?

SUMMARY ANSWER

Synergistic interactions were detected between SNPs, including a non-synonymous SNP, and diplotypes within IGF2R and ADAMTS19 which may contribute to POF; however, there was no correlation with POF in a single SNP model after Bonferroni correction.

WHAT IS KNOWN ALREADY

IGF2R regulates free IGF2 level, which is involved in steroidogenesis in bovine granulosa cells. ADAMTS19 expression is higher in the murine embryonic ovary than in the embryonic testis during sexual differentiation, and an ADAMTS19 SNP (rs246246) showed a possible association with POF in a genome-wide association study in Caucasian women.

STUDY DESIGN, SIZE, DURATION

This study analyzed interactions between SNPs and diplotypes within IGF2R and ADAMTS19 as well as SNPs within the two genes. In Stage I, a total of 120 patients with POF and 152 female controls were recruited. All patients were diagnosed with POF at the CHA hospital in Seoul, Korea, and were recruited between 1994 and 2004. The 152 controls were recruited from Chungju, Korea, as part of another study that was conducted from April 2002 to March 2004. For Stage II, we obtained genotype data for an additional 1641 female controls, recruited in Ansung and Ansan from 2001 to 2008, from the Korean Genome Epidemiology Study (KoGES).

PARTICIPANTS/MATERIALS, SETTING, METHODS

In Stage I, the GoldenGate assay with VeraCode technology was used to genotype SNPs in IGF2R and ADAMTS19. In Stage II, we obtained genotype data for IGF2R and ADAMTS19 using Affymetrix Genome-Wide Human SNP array 5.0 and imputed data by the IMPUTE program from the KoGES. To identify POF-associated SNPs, logistic regression analysis in an additive model was performed using the PLINK tool. Synergistic interactions between SNPs and diplotypes within IGF2R and ADAMTS19 were analyzed by logistic regression analysis in three alternative models.

MAIN RESULTS AND THE ROLE OF CHANCE

In Stage I, 13 combinations of SNPs showed significant synergistic interactions after Bonferroni correction [the strongest association had odds ratio (OR) = 5.77, 95% confidence interval (CI): 2.26-14.75, P = 0.00025]. In Stage II and combined analyses, two and four combinations, respectively, of the significant results in Stage I showed significant synergistic interactions after Bonferroni correction. For interactions between diplotypes in block 2 of IGF2R and block 3 of ADAMTS19 in Stage I, we found 17 synergistic interactions with P < 0.0001, but there was no significant interaction after Bonferroni correction. In Stage II and combined analyses, we found that three and seven combinations in the same blocks, respectively, showed significant synergistic interactions after Bonferroni correction (strongest association: OR = 4.12, 95% CI: 2.22-7.62, P = 6.74E-06).

LIMITATIONS, REASONS FOR CAUTION

The sample size for patients with POF in this study was small but, compared with recent reports describing associations between SNPs and POF and considering the low prevalence of POF (1%), the sample size is considered to be reasonable. These results should be confirmed in large-scale studies involving different ethnic groups.

WIDER IMPLICATIONS OF THE FINDINGS

Our results may ultimately provide predictive markers for women at a high risk of POF.

STUDY FUNDING/COMPETING INTERESTS

This study was supported by grants from Basic Science Research Program through the National Research Foundation of Korea (NRF), which is funded by the Ministry of Education (2009-0093821, 2011-0010637). There are no competing interests.

Follicle stimulating hormone modulates ovarian stem cells through alternately spliced receptor variant FSH-R3

BACKGROUND

We have earlier reported that follicle stimulating hormone (FSH) modulates ovarian stem cells which include pluripotent, very small embryonic-like stem cells (VSELs) and their immediate descendants 'progenitors' termed ovarian germ stem cells (OGSCs), lodged in adult mammalian ovarian surface epithelium (OSE). FSH may exert pleiotropic actions through its alternatively spliced receptor isoforms. Four isoforms of FSH receptors (FSHR) are reported in literature of which FSH-R1 and FSH-R3 have biological activity. Present study was undertaken to identify FSHR isoforms mediating FSH action on ovarian stem cells, using sheep OSE cells culture as the study model.

METHODS

Cultures of sheep OSE cells (a mix of epithelial cells, VSELs, OGSCs and few contaminating red blood cells) were established with and without FSH 5IU/ml treatment. Effect of FSH treatment on self-renewal of VSELs and their differentiation into OGSCs was studied after 15 hrs by qRT-PCR using markers specific for VSELs (Oct-4A, Sox-2) and OGSCs (Oct-4). FSH receptors and its specific transcripts (R1 and R3) were studied after 3 and 15 hrs of FSH treatment by immunolocalization, in situ hybridization and qRT-PCR. FSHR and OCT-4 were also immuno-localized on sheep ovarian sections, in vitro matured follicles and early embryos.

RESULTS

FSH treatment resulted in increased stem cells self-renewal and clonal expansion evident by the appearance of stem cell clusters. FSH receptors were expressed on ovarian stem cells whereas the epithelial cells were distinctly negative. An increase in R3 mRNA transcripts was noted after 3 hrs of FSH treatment and was reduced to basal levels by 15 hrs, whereas R1 transcript expression remained unaffected. Both FSHR and OCT-4 were immuno-localized in nuclei of stem cells, showed nuclear or ooplasmic localization in oocytes of primordial follicles and in cytoplasm of granulosa cells in growing follicles.

CONCLUSIONS

FSH modulates ovarian stem cells via FSH-R3 to undergo potential self-renewal, clonal expansion as 'cysts' and differentiation into oocytes. OCT-4 and FSHR proteins (required initially to maintain pluripotent state of VSELs and for FSH action respectively) gradually shift from nuclei to cytoplasm of developing oocytes and are later possibly removed by surrounding granulosa cells as the oocyte prepares itself for fertilization.

Computational modelling of bovine ovarian follicle development

Background

The development of ovarian follicles hinges on the timely exposure to the appropriate combination of hormones. Follicle stimulating hormone (FSH) and luteinizing hormone (LH) are both produced in the pituitary gland and are transported via the blood circulation to the thecal layer surrounding the follicle. From there both hormones are transported into the follicle by diffusion. FSH-receptors are expressed mainly in the granulosa while LH-receptors are expressed in a gradient with highest expression in the theca. How this spatial organization is achieved is not known. Equally it is not understood whether LH and FSH trigger distinct signalling programs or whether the distinct spatial localization of their G-protein coupled receptors is sufficient to convey their distinct biological function.

Results

We have developed a data-based computational model of the spatio-temporal signalling processes within the follicle and (i) predict that FSH and LH form a gradient inside the follicle, (ii) show that the spatial distribution of FSH- and LH-receptors can arise from the well known regulatory interactions, and (iii) find that the differential activity of FSH and LH may well result from the distinct spatial localisation of their receptors, even when both receptors respond with the same intracellular signalling cascade to their ligand.

Conclusion

The model integrates the large amount of published data into a consistent framework that can now be used to better understand how observed defects translate into failed follicle maturation.

A new approach to primary ovarian insufficiency

There is a need for a new approach to managing women with primary ovarian insufficiency. This condition is a serious chronic disease that may have far reaching effects on physical and emotional health. An integrative and collaborative approach to management works best. To maintain wellness, most women with primary ovarian insufficiency need to reassess their primary source of meaning and purpose in life and how this diagnosis may have threatened that part of who they are. They also need assessment with regard to bone health, thyroid and adrenal function, determination of FMR1 premutation and karyotype status, and ongoing estradiol-progestin hormone replacement.

The genetic basis of female reproductive disorders: etiology and clinical testing

With the advent of improved molecular biology techniques, the genetic basis of an increasing number of reproductive disorders has been elucidated. Mutations in at least 20 genes cause hypogonadotropic hypogonadism including Kallmann syndrome in about 35-40% of patients. The two most commonly involved genes are FGFR1 and CHD7. When combined pituitary hormone deficiency includes hypogonadotropic hypogonadism as a feature, PROP1 mutations are the most common of the six genes involved. For hypergonadotropic hypogonadism, mutations in 14 genes cause gonadal failure in 15% of affected females, most commonly in FMR1. In eugonadal disorders, activating FSHR mutations have been identified for spontaneous ovarian hyperstimulation syndrome; and WNT4 mutations have been described in mullerian aplasia. For other eugonadal disorders, such as endometriosis, polycystic ovary syndrome, and leiomyomata, specific germline gene mutations have not been identified, but some chromosomal regions are associated with the corresponding phenotype. Practical genetic testing is possible to perform in both hypogonadotropic and hypergonadotropic hypogonadism and spontaneous ovarian hyperstimulation syndrome. However, clinical testing for endometriosis, polycystic ovary syndrome, and leiomyomata is not currently practical for the clinician.

Gonadal dysgenesis and the Mayer-Rokitansky-Kuster-Hauser Syndrome in a girl with a 46, XX karyotype: A case report and review of literature

Mayer-Rokitansky-Kuster-Hauser (MRKH) is a characteristic syndrome in which the Mullerian structures are absent or rudimentary. It is also associated with anomalies of the genitourinary and skeletal systems. Its association with gonadal dysgenesis is extremely rare and appears to be fortuitous, independent of chromosomal anomalies. We report such a case in a 21-year-old girl who presented primary amenorrhea and impuberism. The endocrine study revealed hypergonadotrophic hypogonadism. The karyotype was normal, 46, XX. No chromosome Y was detected at the fluorescence in situ hybridization (FISH) analysis. Internal genitalia could not be identified on the pelvic ultrasound and pelvic magnetic resonance imaging. Laparoscopy disclosed concomitant ovarian dysgenesis and MRKH syndrome. There were no other associated malformations. Hormonal substitution therapy with oral conjugated estrogens was begun. The patient has been under regular follow-up for the last two years and is doing well.

Mutations in LARS2, encoding mitochondrial leucyl-tRNA synthetase, lead to premature ovarian failure and hearing loss in Perrault syndrome

The genetic causes of premature ovarian failure (POF) are highly heterogeneous, and causative mutations have been identified in more than ten genes so far. In two families affected by POF accompanied by hearing loss (together, these symptoms compose Perrault syndrome), exome sequencing revealed mutations in LARS2, encoding mitochondrial leucyl-tRNA synthetase: homozygous c.1565C>A (p.Thr522Asn) in a consanguineous Palestinian family and compound heterozygous c.1077delT and c.1886C>T (p.Thr629Met) in a nonconsanguineous Slovenian family. LARS2 c.1077delT leads to a frameshift at codon 360 of the 901 residue protein. LARS2 p.Thr522Asn occurs in the LARS2 catalytic domain at a site conserved from bacteria through mammals. LARS2 p.Thr629Met occurs in the LARS2 leucine-specific domain, which is adjacent to a catalytic loop critical in all species but for which primary sequence is not well conserved. A recently developed method of detecting remote homologies revealed threonine at this site in consensus sequences derived from multiple-species alignments seeded by human and E. coli residues at this region. Yeast complementation indicated that LARS2 c.1077delT is nonfunctional and that LARS2 p.Thr522Asn is partially functional. LARS2 p.Thr629Met was functional in this assay but might be insufficient as a heterozygote with the fully nonfunctional LARS2 c.1077delT allele. A known C. elegans strain with the protein-truncating alteration LARS-2 p.Trp247Ter was confirmed to be sterile. After HARS2, LARS2 is the second gene encoding mitochondrial tRNA synthetase to be found to harbor mutations leading to Perrault syndrome, further supporting a critical role for mitochondria in the maintenance of ovarian function and hearing.

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.

Signaling of an allosteric, nanomolar potent, low molecular weight agonist for the follicle-stimulating hormone receptor

Follicle-stimulating hormone (FSH) activates FSH receptors (FSHR) in granulosa cells to induce follicle differentiation, growth and estradiol production. FSH is used clinically to treat female infertility and is administered by injection. To increase patient convenience and compliance, compound homogeneity and composition, low molecular weight (LMW), orally bioavailable, FSHR agonists are now being developed to replace FSH. In this study, we present the signaling mechanisms of a newly developed LMW dihydropyridine agonist of the FSHR, Org 214444-0. Org 214444-0 is shown to be a stereoselective, nanomolar potent FSHR agonist and selective over the structurally related LHR and TSHR. Org 214444-0 is an allosteric agonist interacting with the transmembrane region of the FSHR. When co-incubated with FSH, Org 214444-0 augments FSH's potency in binding (6.5-fold) and adenylyl cyclase/cAMP activation (3.5-fold) in a concentration-dependent manner. Like FSH, Org 214444-0 induces FSHR internalization and is only marginally effective in stimulating phospholipase C. Moreover, Org 214444-0 stimulates cAMP and estradiol production in human granulosa cells in culture and supports the follicular phase in mature female rats. We conclude that Org 214444-0 is a bonafide FSHR agonist.

Polymorphisms in gonadotropin and gonadotropin receptor genes as markers of ovarian reserve and response in in vitro fertilization

Since gonadotropins are the fundamental hormones that control ovarian activity, genetic polymorphisms may alter gonadal responsiveness to glycoproteins; hence they are important regulators of hormone activity at the target level. The establishment of the pool of primordial follicles takes place during fetal life and is mainly under genetic control. Consequently, single nucleotide polymorphisms (SNPs) in gonadotropins and their receptors do not seem to be associated with any significant modification in the endowment of nongrowing follicles in the ovary. Indeed, the age at menopause, a biological characteristic strongly related to ovarian reserve, as well as markers of functional ovarian reserve such as anti-Müllerian hormone and antral follicle count, are not different in women with different genetic variants. Conversely, some polymorphisms in FSH receptor (FSHR) seem to be associated with modifications in ovarian activity. In particular, studies suggest that the Ser680 genotype for FSHR is a factor of relative resistance to FSH stimulation resulting in slightly higher FSH serum levels, thus leading to a prolonged duration of the menstrual cycle. Moreover, some FSHR gene polymorphisms show a positive association with ovarian response to exogenous gonadotropin administration, hence exhibiting some potential for a pharmacogenetic estimation of the FSH dosage in controlled ovarian stimulation. The study of SNPs of the FSHR gene is an interesting field of research that could provide us with new information about the way each woman responds to exogenous gonadotropin administration during ovulation induction.

Impaired fertility and FSH synthesis in gonadotrope-specific Foxl2 knockout mice

Impairments in pituitary FSH synthesis or action cause infertility. However, causes of FSH dysregulation are poorly described, in part because of our incomplete understanding of mechanisms controlling FSH synthesis. Previously, we discovered a critical role for forkhead protein L2 (FOXL2) in activin-stimulated FSH β-subunit (Fshb) transcription in immortalized cells in vitro. Here, we tested the hypothesis that FOXL2 is required for FSH synthesis in vivo. Using a Cre/lox approach, we selectively ablated Foxl2 in murine anterior pituitary gonadotrope cells. Conditional knockout (cKO) mice developed overtly normally but were subfertile in adulthood. Testis size and spermatogenesis were significantly impaired in cKO males. cKO females exhibited reduced ovarian weight and ovulated fewer oocytes in natural estrous cycles compared with controls. In contrast, ovaries of juvenile cKO females showed normal responses to exogenous gonadotropin stimulation. Both male and female cKO mice were FSH deficient, secondary to diminished pituitary Fshb mRNA production. Basal and activin-stimulated Fshb expression was similarly impaired in Foxl2 depleted primary pituitary cultures. Collectively, these data definitively establish FOXL2 as the first identified gonadotrope-restricted transcription factor required for selective FSH synthesis in vivo.

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.

The consequences of mutations in the reproductive endocrine system

The reproductive activity in male mammals is well known to be regulated by the hypothalamus-pituitary- gonad axis. The hypothalamic neurons secreting gonadotropin releasing hormone (GnRH) govern the reproductive neuroendocrine system by integrating all the exogenous information impinging on themselves. The GnRH synthesized and released from the hypothalamus arrives at the anterior pituitary through the portal vessels, provoking the production of the gonadotropins(follicle-stimulating hormone (FSH) and luteinizing hormone (LH)) at the same time. The gonadotropins affect the gonads to promote spermatogenesis and to secret testosterone. Testosterone acts on the GnRH neurons by a feedback loop through the circulatory system, resulting in the balance of all the hormones by regulating reproductive activities. These hormones exert their effects by acting on their own receptors, which are included in the signal transduction pathways as well. Unexpected aberrants are arised during this course of action of each hormone. This review summarizes these abnormal phenomena, including various mutations of molecules and their actions related to the reproductive function.

The molecular basis of impaired follicle-stimulating hormone action: evidence from human mutations and mouse models

The pituitary gonadotropin follicle-stimulating hormone (FSH) interacts with its membrane-bound receptor to produce biologic effects. Traditional functions of FSH include follicular development and estradiol production in females, and the regulation of Sertoli cell action and spermatogenesis in males. Knockout mice for both the ligand (Fshb) and the receptor (Fshr) serve as models for FSH deficiency, while Fshb and Fshr transgenic mice manifest FSH excess. In addition, inactivating mutations of both human orthologs (FSHB and FSHR) have been characterized in a small number of patients, with phenotypic effects of the ligand disruption being more profound than those of its receptor. Activating human FSHR mutants have also been described in both sexes, leading to a phenotype of normal testis function (male) or spontaneous ovarian hyperstimulation syndrome (females). As determined from human and mouse models, FSH is essential for normal puberty and fertility in females, particularly for ovarian follicular development beyond the antral stage. In males, FSH is necessary for normal spermatogenesis, but there are differences in human and mouse models. The FSHB mutations in humans result in azoospermia; while FSHR mutations in humans and knockouts of both the ligand and the receptor in mice affect testicular function but do not result in absolute infertility. Available evidence also indicates that FSH may also be necessary for normal androgen synthesis in males and females.

NR5A1 (SF-1) gene variants in a group of 26 young women with XX primary ovarian insufficiency

OBJECTIVE

To determine whether NR5A1 (SF-1) variants are a cause of primary ovarian insufficiency (POI) in 26 young women with similar genetic background.

DESIGN

Genetic and functional mutation study.

SETTING

University hospitals.

PATIENT(S)

Genetic analysis of the NR5A1 gene in 26 XX girls with POI.

INTERVENTION(S)

None.

MAIN OUTCOME MEASURE(S)

NR5A1 molecular and functional analysis.

RESULT(S)

Genetic analysis revealed a new c.763C>T (p.Arg255Cys) mutation and a recurrent c.437G>C (p.Gly146Ala) variant. Functional analysis of the p.Arg255Cys mutant showed a marked decrease in transactivation on the Cyp11a1 and Amh promoters. The p.Gly146Ala variant was identified significantly more often in the patients (46.1%) than in ancestry-matched control subjects (10%).

CONCLUSION(S)

We identified one new NR5A1 mutation in a patient of our POI cohort (prevalence 3.8%). Moreover, although our study is limited in the number of cases, we report the high frequency of the p.Gly146Ala variant in this cohort compared with the ancestry-matched control subjects. This work highlights the important role of SF-1 in ovarian function.

Clinical correlation between premature ovarian failure and a chromosomal anomaly in a 22-year-old Caucasian woman: a case report

Introduction

Premature ovarian failure is defined as the cessation of ovarian activity before the age of 40 years. It is biochemically characterized by low levels of gonadal hormones (estrogens and inhibins) and high levels of gonadotropins (luteinizing hormone and follicle-stimulating hormone).

Case presentation

Our patient, a 22-year-old Caucasian woman under evaluation for infertility, had experienced secondary amenorrhea from the age of 18. No positive family history was noted regarding premature menopause. An examination of our patient’s karyotype showed the presence of a reciprocal translocation, apparently balanced, which had the X chromosome long arm (q13) and the 14 chromosome short arm (p12) with consequent karyotype: 46, X, t(X; 14)(q13;p12).

Conclusions

Our study has underlined that karyotyping is one of the fundamental investigations in the evaluation of amenorrhea. It highlighted a genetic etiology, in the form of a chromosomal abnormality, as the causal factor in amenorrhea.

Clinical characteristics and genetic analysis in women with premature ovarian insufficiency

OBJECTIVE

Premature ovarian insufficiency (POI) is defined as a primary ovarian defect characterized by absent menarche (primary amenorrhea) or premature depletion of ovarian follicles before the age of 40 (secondary amenorrhea) with hypergonadotropism and hypoestrogenism.

METHODS

We studied the clinical, biological, and genetic data related to 50 POI patients with a mean age of menopause of 29 years (94% with secondary amenorrhea, 6% with primary amenorrhea and 15% with a family history of POI). Seventeen patients were affected by endocrine autoimmune diseases, antral follicles were observed in 31 patients by ultrasonography.

RESULTS

Karyotype analysis did not show any abnormality of the X chromosome. No mutation in FSH receptor and GDF-9 genes was reported, while in one patient a variant of BMP-15 gene (A180T) was found. Four patients had fragile X mental retardation 1 gene (FMR1) premutation and one an intermediate sized CGG repeats of the same gene. Two patients with FMR1 premutation were sister and developed secondary amenorrhea at the age of 34 and 37 years. The other two patients presented with oligoamenorrhea at the age of 39 and 34 years. The patient harboured the intermediate sized CGG repeats developed secondary amenorrhea at the age of 33 years.

CONCLUSIONS

The genetic analysis performed on a cohort of patients with POI revealed that 8% had FMR1 premutation and only one patient a previously known variant of BMP-15 gene. No alteration of the karyotype and FSH receptor and GDF-9 genes was evidenced.

[Present and future strategies for women at risk, or suffering from premature ovarian failure (POF)]

The purpose of this review is to present the strategies for fertility preservation that are currently proposed to patients at risk from premature ovarian failure (POF) due to chemotherapy as well as some future solutions that could allow patients already affected by an IOP to recover their fertility. Today, cryo-preservation of pieces of ovarian cortex followed by orthotopic transplantation as well as in vitro maturation of oocytes (IVM) allow preservation of fertility in patients being to undergo an antitumor treatment. However, although promising results have been obtained, the pregnancy rate remains very low. Improvement of these techniques, but also stimulation of resting follicle activation, in vitro folliculogenesis, and culture of putative oogonia that may be present in the adult ovary, are all future opportunities for patients suffering from an IOP, and are currently the subject of intensive researches.

A common Asn680Ser polymorphism in the follicle-stimulating hormone receptor gene is not associated with ovarian response to gonadotropin stimulation in patients undergoing in vitro fertilization

OBJECTIVE

To assess the role of the variant p.Asn680Ser in the follicle-stimulating hormone receptor (FSHR) gene in determining ovarian response in patients undergoing in vitro fertilization (IVF) treatment.

DESIGN

Prospective observational study.

SETTING

Tertiary referral center for reproductive medicine.

PATIENT(S)

Women (n = 421) undergoing their first cycle of controlled ovarian stimulation for IVF and 83 healthy, ethnically matched controls.

INTERVENTION(S)

Baseline pelvic ultrasound and blood tests taken on days 2 to 3 of the cycle for assessment of baseline hormones and for DNA extraction.

MAIN OUTCOME MEASURE(S)

Genotypes for FSHR p.Asn680Ser determined using TaqMan allelic discrimination assay, and ovarian response to gonadotropin treatment classified as normal, poor, or overresponse based on the number of oocytes retrieved.

RESULT(S)

The FSHR p.Asn680Ser genotype frequencies were similar in IVF patients and controls. The number of oocytes retrieved was comparable between patients with different FSHR receptor genotypes. The total amount of gonadotropin used was also similar in all the genotype groups. A logistic regression analysis showed nonstatistically significant twofold difference in the distribution of genotypes between the groups with poor and normal ovarian response.

CONCLUSION(S)

The variant FSHR p.Asn680Ser was not shown to be predictive of ovarian response, but clinically relevant differences cannot be ruled out.

An update on primary ovarian insufficiency

Primary ovarian insufficiency (POI) occurs in about 1% of female population under the age of 40, leading to reproductive problems, an earlier encounter with menopausal symptoms, and complicated diseases. There are three presumable mechanisms involved in the development of POI, namely apoptosis acceleration, follicular maturation blocking and premature follicle activation, through the following studied causes: (i) chromosomal abnormalities or gene mutations: mostly involve X chromosome, such as FMR1 premutation; more and more potentially causal genes have been screened recently; (ii) metabolic disorders such as classic galactosaemia and 17-OH deficiency; (iii) autoimmune mediated ovarian damage: observed alone or with some certain autoimmune disorders and syndromes; but the specificity and sensitivity of antibodies towards ovary are still questionable; (iv) iatrogenic: radiotherapy or chemotherapy used in cancer treatment, as well as pelvic surgery with potential threat to ovaries' blood supply can directly damage ovarian function; (v) virus infection such as HIV and mumps; (vi) toxins and other environmental/lifestyle factors: cigarette smoking, toxins (e.g., 4-vinylcyclohexene diepoxide), and other environmental factors are associated with the development of POI. The etiology of a majority of POI cases is not identified, and is believed to be multifactorial. Strategies to POI include hormone replacement and infertility treatment. Assisted conception with donated oocytes has been proven to achieve pregnancy in POI women. Embryo cryopreservation, ovarian tissue cryopreservation and oocyte cryopreservation have been used to preserve ovarian reserve in women undergoing cancer treatments.

Investigating the role of X chromosome breakpoints in premature ovarian failure

The importance of the genetic factor in the aetiology of premature ovarian failure (POF) is emphasized by the high percentage of familial cases and X chromosome abnormalities account for 10% of chromosomal aberrations. In this study, we report the detailed analysis of 4 chromosomal abnormalities involving the X chromosome and associated with POF that were detected during a screening of 269 affected women. Conventional and molecular cytogenetics were valuable tools for locating the breakpoint regions and thus the following karyotypes were defined: 46,X,der(X)t(X;19)(p21.1;q13.42)mat, 46,X,t(X;2)(q21.33;q14.3)dn, 46,X,der(X)t(X;Y)(q26.2;q11.223)mat and 46,X,t(X;13)(q13.3;q31)dn. A bioinformatic analysis of the breakpoint regions identified putative candidate genes for ovarian failure near the breakpoint regions on the X chromosome or on autosomes that were involved in the translocation event. HS6ST1, HS6ST2 and MATER genes were identified and their functions and a literature review revealed an interesting connection to the POF phenotype. Moreover, the 19q13.32 locus is associated with the age of onset of the natural menopause. These results support the position effect of the breakpoint on flanking genes, and cytogenetic techniques, in combination with bioinformatic analysis, may help to improve what is known about this puzzling disorder and its diagnostic potential.

Frequent polymorphisms of FSH receptor do not influence antral follicle responsiveness to follicle-stimulating hormone administration as assessed by the Follicular Output RaTe (FORT)

PURPOSE

To verify whether carriers of common single-nucleotide polymorphisms (SNPs) of the FSH receptor (FSHR) show reduced responsiveness of antral follicles to FSH administration as assessed by the FORT.

METHODS

We performed a prospective study in a university hospital. Study population consisted of 124 Caucasian IVF-ET candidates. FSHR 307Ala and 680Ser variants were analyzed in haplotypes and as separated genes. Serum FSH, estradiol (E(2)), and anti-Müllerian hormone (AMH) were measured on cycle-day 3. Antral follicle (3-8 mm) count (AFC) and preovulatory follicle (16-22 mm) count (PFC) were performed, respectively, at the achievement of pituitary suppression (before FSH administration) and on the day of hCG administration. Antral follicle responsiveness to FSH administration assessed by the FORT (PFCx100/AFC).

RESULTS

Data concerning baseline and IVF-ET parameters were similar between SNPs carriers and controls. Moreover, FORT was similar for different haplotypes Thr307-Asn680 (45.9%) and Ala307-Ser680 (39.4%) and 307Thr/Ala-Ala/Ala (41.1%; 5.0-91.6%) versus 307Thr/Thr (44.4%; 17.3-83.3%) and in 680Asn/Ser-Ser/Ser (40.0%; 5.0-91.6%) versus 680Asn/Asn (42.2%; 8.3-90.0%) carriers.

CONCLUSIONS

Antral follicle responsiveness to FSH, as far as measured by the FORT, is not influenced by the presence of SNPs of FSHR 307Ala and 680Ser.

Pharmacoperones: a new therapeutic approach for diseases caused by misfolded G protein-coupled receptors

G Protein-coupled receptors (GPCRs) are cell membrane proteins that recognize specific chemical signals such as drugs and hormones and transduce these signals into cellular responses by activating G-proteins. As is the case for all newly synthesized proteins, GPCRs are subjected to conformational scrutiny at the endoplasmic reticulum prior to processing and trafficking to the cell surface membrane. Because of this stringent quality control screening mechanism, mutations that result in protein misfolding frequently lead to retention in the endoplasmic reticulum, aggregation or other misrouting and, eventually, to disease. This article reviews some patents and new therapeutic opportunities based on the misfolding and retention of otherwise functional GPCRs that represent promising approaches to correct conformational abnormalities leading to distinct disease states.

Replication of loci influencing ages at menarche and menopause in Hispanic women: the Women's Health Initiative SHARe Study

Several genome-wide studies have identified loci associated with reproductive traits, such as ages of menarche and menopause, in women of European ancestry. In this study, we investigated the relevance of these loci in minority US Hispanic women. We utilized data from 3468 women who were genotyped as a part of the Women's Health Initiative SNP Health Association Resource. We replicated associations of eight loci (LRP18, LIN28B, CENPW, INHBA, TMEM38B, ZNF483, NFAT5 and OLFM2) with age at menarche, and of two loci (MCM8 and BRSK1/TMEM150B) with age at menopause. The MCM8 locus was also associated with early menopause risk. Three loci (CENPW, MCM8 and BRSK1/TMEM150B) were associated with the length of reproductive lifespan. We provide evidence that genetic variants influencing reproductive traits identified in European populations are also important in minority US Hispanic women.

Sex differences in primary hypertension

Men have higher blood pressure than women through much of life regardless of race and ethnicity. This is a robust and highly conserved sex difference that it is also observed across species including dogs, rats, mice and chickens and it is found in induced, genetic and transgenic animal models of hypertension. Not only do the differences between the ovarian and testicular hormonal milieu contribute to this sexual dimorphism in blood pressure, the sex chromosomes also play a role in and of themselves. This review primarily focuses on epidemiological studies of blood pressure in men and women and experimental models of hypertension in both sexes. Gaps in current knowledge regarding what underlie male-female differences in blood pressure control are discussed. Elucidating the mechanisms underlying sex differences in hypertension may lead to the development of anti-hypertensives tailored to one's sex and ultimately to improved therapeutic strategies for treating this disease and preventing its devastating consequences.

Genome-wide linkage in a highly consanguineous pedigree reveals two novel loci on chromosome 7 for non-syndromic familial Premature Ovarian Failure

Background

The human condition known as Premature Ovarian Failure (POF) is characterized by loss of ovarian function before the age of 40. A majority of POF cases are sporadic, but 10–15% are familial, suggesting a genetic origin of the disease. Although several causal mutations have been identified, the etiology of POF is still unknown for about 90% of the patients.

Methodology/Principal Findings

We report a genome-wide linkage and homozygosity analysis in one large consanguineous Middle-Eastern POF-affected family presenting an autosomal recessive pattern of inheritance. We identified two regions with a LOD_max of 3.26 on chromosome 7p21.1-15.3 and 7q21.3-22.2, which are supported as candidate regions by homozygosity mapping. Sequencing of the coding exons and known regulatory sequences of three candidate genes (DLX5, DLX6 and DSS1) included within the largest region did not reveal any causal mutations.

Conclusions/Significance

We detect two novel POF-associated loci on human chromosome 7, opening the way to the identification of new genes involved in the control of ovarian development and function.

Physiological sex steroid replacement in premature ovarian failure: randomized crossover trial of effect on uterine volume, endometrial thickness and blood flow, compared with a standard regimen

BACKGROUND

Premature ovarian failure (POF) is currently managed by non-physiological sex steroid regimens which are inadequate at optimizing uterine characteristics. Previous short-term studies have demonstrated some benefits of a sex steroid replacement (SSR) regimen devised to replicate the physiological cycle. This study aimed to directly compare the effects of longer-term administration of physiological SSR (pSSR) and standard SSR (sSSR) regimens on the uterine volume, blood flow and endometrial thickness (ET) in women with POF.

METHODS

In a controlled crossover trial, 34 women with POF were randomized to receive 12 months of 4-week cycles of transdermal estradiol and vaginal progesterone (pSSR) followed by 12 months of 4-week cycles of oral ethinylestradiol and norethisterone (sSSR), or vice versa. Each treatment period was preceded by a 2-month washout period. At 0, 3, 6 and 12 months of each treatment period, transvaginal ultrasound examined the uterine volume and ET, as primary end-points, and uterine artery resistance (UARI) and pulsatility indices (UAPI), as secondary end-points. Serum estradiol, progesterone and gonadotrophins were also measured.

RESULTS

Of the 29 women eligible for the uterine analysis, 17 completed the entire study protocol, but 25 women contributed data to statistical analysis of treatment effect. There was a greater estimated mean ET with the use of pSSR (4.8 mm) compared to that with standard therapy (3.0 mm), with an estimated difference of 1.8 mm [95% confidence interval (CI), 0.7 to 2.8, P=0.002]. The estimated mean uterine volume was also greater during physiological treatment (24.8 cm(3)) than during standard treatment (20.6 cm(3)), but the estimated difference of 4.2 cm(3) (95% CI -0.4 to 8.7) was not statitsically significant, P=0.070. The small differences between the two treatments in the mean UARI and mean UAPI were not statistically significant. The estimated treatment differences were fairly constant across the treatment periods, suggesting that prolonged treatment does not increase response.

CONCLUSIONS

pSSR has a greater beneficial effect upon ET in women with POF in comparison with standard therapy. A similar trend was seen for uterine volume. Further studies are required to optimize treatment and to assess pregnancy rate and outcome. Trial Registration www.ClinicalTrials.gov, NCR00732693.

LAMC1 gene is associated with premature ovarian failure

OBJECTIVES

Common variations with modest effect in complex and polygenic disease such as premature ovarian failure (POF) can be detected by a genome wide association study. We performed a genome wide association study to identify predisposing genes associated with an increased risk of POF.

STUDY DESIGN

In stage I, genome wide association study was performed using 24 POF patients and 24 matched controls. A strongly associated region was re-tested to confirm the association with POF in stage II using 98 patients and 218 matched controls.

RESULTS

In the stage I, we found a strongly associated region that was located on chromosome 1q31 and encoded the laminin gamma 1 (LAMC1) gene. All 22 single nucleotide polymorphisms (SNPs) in the LAMC1 formed a linkage disequilibrium block and two haplotypes were significantly associated with POF. In the stage II, 14 SNPs, the majority of which were SNPs located in coding region and tagging SNPs, were genotyped. Distributions of 9 SNPs of them including one nonsynonymous SNP (rs20558) and one haplotype (HT1, C-C-T-G-C-C-A-T-T-C) were significantly higher in POF patients than in control group (86.6% and 74.5%, respectively, OR=2.209, CI: 1.139-4.284, P=0.017).

CONCLUSIONS

We showed for the first time that LAMC1 is significantly associated with POF, and specifically, possession of at least one HT1 was associated with susceptibility to POF. This result means that HT1 may co-exist with causative variant for susceptibility to POF in linkage disequilibrium and that the LAMC1 may be involved in POF pathogenesis.

Epistasis between the HSD17B4 and TG polymorphisms is associated with premature ovarian failure

OBJECTIVE

To identify whether epistasis between TG and HSD17B4 and whether polymorphisms in HSD17B4 are associated with premature ovarian failure (POF).

DESIGN

Case-control genetic association study.

SETTING

Research laboratory of a university.

PATIENT(S)

Female patients with POF (98) and controls (218) of Korean ethnicity participated in this study.

INTERVENTION(S)

None.

MAIN OUTCOME MEASURE(S)

Genotype distribution, haplotype (HT) inference, and gene-gene interaction.

RESULT(S)

Distribution of one haplotype (A-G-A-A-G-G) on the HSD17B4 gene was significantly different between the POF group and the control group in a dominant model. In addition, the combined effect of the single nucleotide polymorphisms (SNPs) HSD17B4 rs28943592 and TG rs2076740 was significantly associated with POF (odds ratio = 7.74, 95% confidence interval = 1.67-35.94), although a significant association was not observed in the single SNP model.

CONCLUSION(S)

A haplotype in the HSD17B4 gene was identified that was significantly associated with resistance to POF. In addition, epistasis between two missense SNPs (rs28943592, rs2076740) located in HSD17B4 and TG was significantly associated with susceptibility to POF.

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

Background

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

Methods

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

Results

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

Conclusions

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

Anti-Mullerian hormone as a predictor of follicular reserve in ovarian insufficiency: special emphasis on FSH-resistant ovaries

BACKGROUND

Anti-Müllerian hormone (AMH) is secreted by ovarian granulosa cells and its serum levels reflect ovarian follicle reserve. The main objective of this study was to test the use of AMH assay in identifying women with primary amenorrhea (PA) and existing follicles and to study follicle phase dependent AMH secretion.

METHODS

Serum levels of AMH were measured in subjects with FSH-resistant ovaries (FSHRO, n= 12), primary ovarian insufficiency (POI) with PA (n= 11) or secondary amenorrhea (SA n= 20) of unknown etiology, and controls (n= 23), and in Turner syndrome (TS) [45,X (n= 18), mosaicism (n= 7), structural X chromosome abnormalities (SCA, n= 10)], and healthy controls (n= 34).

RESULTS

Serum levels of AMH in women with FSHRO were comparable with those in control women (2.76 ± 2.37 versus 3.77 ± 2.36 ng/ml) and significantly higher than in women with PA (0.05 ± 0.04 ng/ml; P < 0.001) or SA of unknown origin (0.12 ± 0.20 ng/ml; P < 0.001). TS girls/women with 45,X or SCA had low serum AMH levels (0.13 ± 0.09 and 0.27 ± 0.19 ng/ml) compared with their controls (3.34 ± 2.23 ng/ml) or subjects with mosaicism (2.33 ± 2.81 ng/ml). AMH expression was detected in granulosa cells of women with FSHRO but not in any of the 45,X fetal ovarian specimens.

CONCLUSIONS

A serum AMH assay could be used to identify patients with decreasing ovarian reserves and POI. Moreover, our results support the notion that AMH is secreted mainly by small non-selected follicles, since follicular granulosa cells were AMH-positive and serum AMH levels were normal/low normal in women with FSHRO, who lack follicle development beyond the small antral stage.

Anti-Müllerian hormone: an ovarian reserve marker in primary ovarian insufficiency

Primary ovarian insufficiency (POI), also known as premature ovarian failure, is a disorder of infertility characterized by amenorrhoea, low estrogen levels and increased gonadotropin levels in women aged <40 years. POI is the result of premature exhaustion of the follicle pool or can be attributed to follicular dysfunction, for example, owing to mutations in the follicle-stimulating hormone receptor or steroidogenic cell autoimmunity. Moreover, advances in cancer therapeutics over the past decades have led to increasing survival rates for both paediatric and adult malignancies. Given the gonadotoxic effect of many cancer treatments, more women develop POI. A marker that predicts whether women are at risk of POI would, therefore, aid in early diagnosis and fertility counselling. Anti-Müllerian hormone (AMH), a growth factor produced solely by small, growing follicles in the ovary, might constitute such a marker, as serum levels of this hormone correlate strongly with the number of growing follicles. In addition, AMH could potentially help assess the progression of ovarian senescence, as serum AMH levels are independent of hypothalamic-pituitary-gonadal axis function and decrease to undetectable levels at menopause. In cancer survivors, serum AMH levels correlate with the extent of gonadal damage. In this Review, we provide an overview of the current studies that have measured AMH in women with POI of various aetiologies and discuss its possible application as a marker to determine ovarian reserve.

Pharmacological chaperones correct misfolded GPCRs and rescue function: protein trafficking as a therapeutic target

G-protein-coupled receptors (GPCRs) are a large superfamily of plasma membrane proteins that play central roles in transducing endocrine, neural and -sensory signals. In humans, more than 30 disorders are associated with mutations in GPCRs and these proteins are common drug development targets, with 30-50% of drugs targeting them. GPCR mutants are frequently misfolded, recognized as defective by the cellular quality control system, retained in the endoplasmic reticulum and do not traffic to the plasma membrane. The use of small molecules chaperones (pharmacological chaperones or "pharmacoperones") to rescue misfolded GPCRs has provided a new approach for treatment of human diseases caused by misfolding and misrouting. This chapter provides an overview of the molecular basis of this approach using the human gonadotropin-releasing hormone receptor (hGnRHR) as model for treatment of conformational diseases provoked by -misfolded GPCRs.

Novel pathways in gonadotropin receptor signaling and biased agonism

Gonadotropins play a central role in the control of male and female reproduction. Selective agonists and antagonists of gonadotropin receptors would be of great interest for the treatment of infertility or as non steroidal contraceptive. However, to date, only native hormones are being used in assisted reproduction technologies as there is no pharmacological agent available to manipulate gonadotropin receptors. Over the last decade, there has been a growing perception of the complexity associated with gonadotropin receptors' cellular signaling. It is now clear that the Gs/cAMP/PKA pathway is not the sole mechanism that must be taken into account in order to understand these hormones' biological actions. In parallel, consistent with the emerging paradigm of biased agonism, several examples of ligand-mediated selective signaling pathway activation by gonadotropin receptors have been reported. Small molecule ligands, modulating antibodies interacting with the hormones and glycosylation variants of the native glycoproteins have all demonstrated their potential to trigger such selective signaling. Altogether, the available data and emerging concepts give rise to intriguing opportunities towards a more efficient control of reproductive function and associated disorders.

Effects of polymorphisms in gonadotropin and gonadotropin receptor genes on reproductive function

Gonadotropins, the action of which is mediated at the level of their gonadal receptors, play a key role in sexual development, reproductive functions and in metabolism. The involvement of the gonadotropins and their receptor genotypes on reproductive function are widely studied. A large number of gonadotropins and their receptors gene polymorphisms are known, but the only one considerable as a clear, absolute genetic marker of reproductive features or disfunctions is the FSHR Asn680Ser polymorphism, since it modulates ovarian response to FSH. The aim of these studies would to be the prediction of the genetic causes of sex-related diseases to enable a customized clinical setting based on individual response of patients undergoing gonadotropin stimulation. In this review we discuss the latest information about the effects of polymorphisms of the gonadotropins and their receptor genes on reproductive functions of both male and female, and discuss their patho-physiological implications.

Does ovarian autoimmunity play a role in the pathophysiology of premature ovarian insufficiency?

Premature Ovarian Failure (POF) is an important cause of amenorrhoea and infertility. However some women may spontaneously ovulate and conceive. Primary ovarian insufficiency (POI) is thus the preferred term. POF / POI is multifactorial in etiology. Autoimmunity is an important mechanism for accelerated destruction of ovarian follicles. The present review focuses on the role of autoimmunity in the pathophysiology of POI. Antibodies to multiple ovarian antigens have been proposed as markers of ovarian autoimmunity. However, there has been lack of clinically proven sensitive and specific serum tests to confirm autoimmune involvement in POI. The review details recently developed specific test for antiovarian antibodies (AOA) that has enabeled identification of different molecular antigenic targets in the ovary. The application of this specific test for AOA has brought to light the need for screening for autoimmunity prior to patients undergoing IVF technique.

XX ovarian dysgenesis is caused by a PSMC3IP/HOP2 mutation that abolishes coactivation of estrogen-driven transcription

XX female gonadal dysgenesis (XX-GD) is a rare, genetically heterogeneous disorder characterized by lack of spontaneous pubertal development, primary amenorrhea, uterine hypoplasia, and hypergonadotropic hypogonadism as a result of streak gonads. Most cases are unexplained but thought to be autosomal recessive. We elucidated the genetic basis of XX-GD in a highly consanguineous Palestinian family by using homozygosity mapping and candidate-gene and whole-exome sequencing. Affected females were homozygous for a 3 bp deletion (NM_016556.2, c.600_602del) in the PSMC3IP gene, leading to deletion of a glutamic acid residue (p.Glu201del) in the highly conserved C-terminal acidic domain. Proteasome 26S subunit, ATPase, 3-Interacting Protein (PSMC3IP)/Tat Binding Protein Interacting Protein (TBPIP) is a nuclear, tissue-specific protein with multiple functions. It is critical for meiotic recombination as indicated by the known role of its yeast ortholog, Hop2. Through the C terminus (not present in yeast), PSMC3IP also coactivates ligand-driven transcription mediated by estrogen, androgen, glucocorticoid, progesterone, and thyroid nuclear receptors. In cell lines, the p.Glu201del mutation abolished PSMC3IP activation of estrogen-driven transcription. Impaired estrogenic signaling can lead to ovarian dysgenesis both by affecting the size of the follicular pool created during fetal development and by failing to counteract follicular atresia during puberty. PSMC3IP joins previous genes known to be mutated in XX-GD, the FSH receptor, and BMP15, highlighting the importance of hormonal signaling in ovarian development and maintenance and suggesting a common pathway perturbed in isolated XX-GD. By analogy to other XX-GD genes, PSMC3IP is also a candidate gene for premature ovarian failure, and its role in folliculogenesis should be further investigated.

Novel NOBOX loss-of-function mutations account for 6.2% of cases in a large primary ovarian insufficiency cohort

Primary ovarian insufficiency (POI) is a disorder associated with female infertility, which affects approximately 1% of women under 40 years of age. A genetic component has been suggested as one possible cause of the majority of cases of nonsyndromic forms. Newborn Ovary Homeobox (NOBOX) is an ovary-specific gene, playing a critical role in ovary in mice, as its absence leads to sterility mimicking a POI. In this study, we sequenced NOBOX in a cohort of 178 women with idiopathic POI. Among 19 identified variations, we described one nonsense (c.907C>T/p.R303X) and four missense (c.271G>T/p.G91W, c.349C>T/p.R117W, c.1025G>C/p.S342T, and c.1048G>T/p.V350L) NOBOX heterozygous mutations in 12 patients. We reproduced each of the five mutations and tested their effects on the signaling activity in transfected cells. We demonstrated that these mutations compromised the ability of the proteins to bind to and transactivate the well-known growth differentiation factor 9 (GDF9) promoter. The pattern of our findings suggests that the genetic mechanism in humans responsible for POI in women involves haploinsufficiency rather than dominant negative gene action. The identification, characterization, and the very high 6.2% prevalence of these new mutations in POI patients suggest considering NOBOX as the first autosomal candidate gene involved in this syndrome.

Contemporary genetic technologies and female reproduction

BACKGROUND

The Fifth Evian Annual Reproduction (EVAR) Workshop Meeting discussed knowledge regarding contemporary genetics in female reproduction.

METHODS

Specialist reproductive medicine clinicians and geneticists delivered presentations based on published literature and current research. The content of this report is based on the expert presentations and subsequent group discussions that took place during this Workshop.

RESULTS

Numerous ovarian genes with a role in infertility have been identified. Future challenges for genetic screening of patients, such as those with polycystic ovary syndrome, primary ovarian insufficiency or endometriosis, include the identification of high-throughput strategies and how to apply these findings to infertile patients. The identification of high-quality embryos in IVF using objective technologies remains a high priority in order to facilitate single-embryo transfer. Gene expression profiling of cumulus cells surrounding the oocyte, and proteomic and metabolomic approaches in embryo culture media may significantly improve non-invasive embryo quality assessment.

CONCLUSIONS

The way forward in advancing the knowledge of genes involved in reproduction was considered to be through genome-wide association studies involving large numbers of patients. Establishing international collaboration is required to enable the application of such technologies in sufficient numbers of patients.