Ovarian differentiation and gonadal failure

X chromosome rearrangement associated with premature ovarian insufficiency as diagnosed by molecular cytogenetic methods: a case report and review of the literature

BACKGROUND

Premature ovarian insufficiency (POI) is a clinical condition characterized by ovarian dysfunction in women under 40. The etiology of most POI cases remains unidentified and is believed to be multifactorial, including factors such as autoimmunity, metabolism, infection, and genetics. POI exhibits significant genetic heterogeneity, and it can result from chromosomal abnormalities and monogenic defects.

CASE PRESENTATION

The study participant, a 33-year-old woman, presented with a history of irregular menstruation that commenced two years ago, progressing to prolonged menstrual episodes and eventual cessation. The participant exhibits a rearrangement of the X chromosome, characterized by heterozygosity duplication on the long arm and heterozygosity deletion on the short arm by whole exome sequencing(WES) combined with cell chromosome detection.

CONCLUSIONS

This study expands the spectrum of mutations associated with POI resulting from X chromosomal abnormalities. WES-Copy number variation analysis, in conjunction with chromosome karyotype analysis and other detection techniques, can provide a more comprehensive understanding of the genetic landscape underlying complex single or multi-system diseases.

Ovarian Reserve Disorders, Can We Prevent Them? A Review

The ovarian reserve is finite and begins declining from its peak at mid-gestation until only residual follicles remain as women approach menopause. Reduced ovarian reserve, or its extreme form, premature ovarian insufficiency, stems from multiple factors, including developmental, genetic, environmental exposures, autoimmune disease, or medical/surgical treatment. In many cases, the cause remains unknown and resulting infertility is not ultimately addressed by assisted reproductive technologies. Deciphering the mechanisms that underlie disorders of ovarian reserve could improve the outcomes for patients struggling with infertility, but these disorders are diverse and can be categorized in multiple ways. In this review, we will explore the topic from a perspective that emphasizes the prevention or mitigation of ovarian damage. The most desirable mode of fertoprotection is primary prevention (intervening before ablative influence occurs), as identifying toxic influences and deciphering the mechanisms by which they exert their effect can reduce or eliminate exposure and damage. Secondary prevention in the form of screening is not recommended broadly. Nevertheless, in some instances where a known genetic background exists in discrete families, screening is advised. As part of prenatal care, screening panels include some genetic diseases that can lead to infertility or subfertility. In these patients, early diagnosis could enable fertility preservation or changes in family-building plans. Finally, Tertiary Prevention (managing disease post-diagnosis) is critical. Reduced ovarian reserve has a major influence on physiology beyond fertility, including delayed/absent puberty or premature menopause. In these instances, proper diagnosis and medical therapy can reduce adverse effects. Here, we elaborate on these modes of prevention as well as proposed mechanisms that underlie ovarian reserve disorders.

Turner syndrome with Xp deletions and rare endometrial abnormalities: A case report

RATIONALE

Turner syndrome (TS) is a genetic disorder associated with abnormalities of the X chromosome related to ovarian function, but whether it is associated with endometrial abnormalities is still not clear.

PATIENT CONCERNS

We report the case of a 26-year-old Han Chinese woman with TS and Xp11.2 deletion, presenting with short final stature, ovarian hypofunction, unexplained cystic dilatation of the entire endometrium, and endometrial thickening.

DIAGNOSES

The patient was diagnosed with chromosome Xp11.2 deletion through cytogenetic analysis and ultrasonic and endometrial pathology.

INTERVENTIONS

The patient was treated with conventional in vitro fertilization preimplantation genetic testing for 1 cycle.

OUTCOMES

Cytogenetic examination showed karyotype 45, X, del (X) del (p11, 2). Ultrasonic examination showed uneven endometrium thickness and a full-stage cystic dilation echo. After 1 cycle of in vitro fertilization treatment, 4 eggs were obtained without forming an available embryo.

LESSONS

To our knowledge, the present case is the first report of a patient with TS with Xp deletions and ultrasound imaging endometrial abnormalities. Our findings expand the phenotypic spectrum of TS and may provide a reference for other clinicians.

Effects of chromosomal abnormalities on pregnancy outcomes in female undergoing artificial insemination with donor's sperm

This study aimed to evaluate the clinical characteristics, pregnancy outcomes and prognostic factors for pregnancy of female with chromosomal abnormalities (CAs) after artificial insemination with donor's sperm (AID) treatment.A retrospective case-control study was analyzed by using the data of 29 female patients with CA and 116 controlled patients with normal karyotype (1:4 ratio) who underwent AID cycles at Guangdong Family Planning Special Hospital from January 2011 to December 2017. In all cases, reproductive histories were collected, and the cytogenetic analysis was performed by Trypsin-Giemsa banding and karyotyping. The embryos were fertilized via intracervical or intrauterine insemination. Clinical characteristic variables were compared.The prevalence of CA was found to be 0.29% in the whole AID population. The live birth rates of CA group and controlled group were 41.4% and 31.0% (P = .29) respectively. Compared to normal karyotype group, patients with CA showed higher rate of primary infertility (93.1% vs 75.9%, P = .049); Multivariate analysis demonstrated that ovarian stimulation (odds ratio, 3.055; 95% confidence interval, 1.421-6.568; P = .004) was associated with adverse pregnancy outcomes in female patients with AID treatment.For the infertility CA patients who were phenotypically normal, AID was a suitable choice, whereas ovarian stimulation results in an improvement in the pregnancy rate.

Chromosome Abnormalities Related to Reproductive and Sexual Development Disorders: A 5-Year Retrospective Study

Chromosomal abnormalities are the main genetic risk factor associated with reproductive and sexual development disorders (DSD). The goal of this study is to retrospectively evaluate the frequency of chromosomal aberrations in Moroccan subjects with problems of procreation or sexual ambiguity. A total of 1005 individuals, including 170 infertile couples, underwent cytogenetic analysis in the Cytogenetic Laboratory of the Pasteur Institute of Morocco. Heparinized blood samples were processed according to the standard karyotype method. A total (81.5%) of the patients studied had a normal karyotype, while the remaining (18.5%) patients had an abnormal karyotype. Female patients had more chromosomal abnormalities (52%) than male patients (48%). These chromosomal aberrations included 154 cases (83%) of sex chromosomal abnormalities, the most common being Turner's syndrome and Klinefelter's syndrome, and 31 cases (17%) had autosomal aberrations, especially chromosome 9 reversal (inv(9)(p12;q13)). The present data shows that among 170 couples, 10.6% had chromosomal abnormalities mainly involved in the occurrence of recurrent miscarriages. Genotype-phenotype correlations could not be made, and therefore, studies using more resolutive molecular biology techniques would be desirable.

FMR1 expression in human granulosa cells and variable ovarian response: control by epigenetic mechanisms

In humans, FMR1 (fragile X mental retardation 1) is strongly expressed in granulosa cells (GCs) of the female germline and apparently controls efficiency of folliculogenesis. Major control mechanism(s) of the gene transcription rate seem to be based on the rate of CpG-methylation along the CpG island promoter. Conducting CpG-methylation-specific bisulfite-treated PCR assays and subsequent sequence analyses of both gene alleles, revealed three variably methylated CpG domains (FMR1-VMR (variably methylated region) 1, -2, -3) and one completely unmethylated CpG-region (FMR1-UMR) in this extended FMR1-promoter-region. FMR1-UMR in the core promoter was exclusively present only in female GCs, suggesting expression from both gene alleles, i.e., escaping the female-specific X-inactivation mechanism for the second gene allele. Screening for putative target sites of transcription factors binding with CpG methylation dependence, we identified a target site for the transcriptional activator E2F1 in FMR1-VMR3. Using specific electrophoretic mobility shift assays, we found E2F1 binding efficiency to be dependent on CpG-site methylation in its target sequence. Comparative analysis of these CpGs revealed that CpG 94-methylation in primary GCs of women with normal and reduced efficiency of folliculogenesis statistically significant differences. We therefore conclude that E2F1 binding to FMR1-VMR3 in human GCs is part of an epigenetic mechanism regulating the efficiency of human folliculogenesis. Our data indicate that epigenetic mechanisms may control GC FMR1-expression rates.

Genetics of Primary Ovarian Insufficiency

The diagnosis of primary ovarian insufficiency (POI) has untold effects on women and a better understanding alongside potential treatments are paramount to improve quality of life of these women. Various causes have been linked to the development of POI with genetics playing a key role. A better understanding of the genetics of POI could lead to earlier diagnosis and broaden fertility options. This chapter discusses previously known and more recently discovered genes that have been implicated in the development of POI. It explores the varying phenotypic expressions of some genes in different populations and areas for further research in the genetics of POI.

Study of frequency and types of chromosomal abnormalities in phenotypically female patients with amenorrhea in Eastern Indian population

AIM

This comprehensive review article aims to comprehend the frequency and prevalence of chromosomal abnormalities in both primary amenorrhea (PA) and secondary amenorrhea (SA) cases and correlating it with their phenotypes, clinical features and hormonal profiles.

METHODS

Research publications on prevalence of chromosomal abnormalities in both PA and SA cases worldwide and its etiology, clinical features, hormonal profiles; their correlation with chromosomal profiles were searched for on the internet, including general search engines and respective scientific sites. Only published, relevant and authentic data conducted on phenotypically female patients were considered. Another aspect of amenorrhea occurs due to several clinical conditions apart from cytogenetic viewpoint were not considered or discussed in detail.

RESULTS

As literature study suggests; considering various etiology of amenorrhea counting anatomic defect of the hypothalamus or genetic defect, and various acquired causes of chromosomal anomalies contribute to be one of the major etiologies of both PA and SA; ranging from 15.9% to 63.3% in case of PA and from 3.9% to 44.4% in case of SA. In spite of the presence of any other factors responsible condition, the genetic factors need to be emphasized, which might include single gene disorders or chromosomal disorders. Individuals with chromosomal anomalies reported a wide range of abnormalities in phenotypes, as well as in other clinical features and hormonal profiles.

CONCLUSION

This comprehensive review is the first structured review article that encompasses the cytogenetic profile of the amenorrhea cases and correlating it with their phenotypes, clinical features and hormonal profiles from Eastern India.

Turner syndrome with rapidly progressive puberty: a case report and literature review

This report describes a clinically rare and atypical case of 46,X,idic(X)(q21.32)/45,X-type Turner syndrome with rapidly progressive puberty development. After 11 months of treatment with recombinant human growth hormone (rhGH), the child’s height increased. After 18 months of treatment with rhGH, the child showed secondary sex characteristics. The child was followed up for 1 year after the appearance of the secondary sex characteristics, and regular menses were still present. This case indicates that modern molecular biology techniques should be used rationally to further investigate the existence of X-chromosome translocations and occult chimeras to prevent misdiagnosis.

A high-resolution X chromosome copy-number variation map in fertile females and women with primary ovarian insufficiency

PURPOSE

Sex-biased expression of genes on the X chromosome is accomplished by a complex mechanism of dosage regulation that leads to anatomical and physiological differences between males and females. Copy-number variations (CNVs) may impact the human genome by either affecting gene dosage or disturbing a chromosome structural and/or functional integrity.

METHODS

We performed a high-resolution CNV profiling to investigate the X chromosome integrity in cohorts of 269 fertile females and 111 women affected with primary ovarian insufficiency (POI) and assessed CNVs impact into functional and nonfunctional genomic elements.

RESULTS

In POI patients, we observed a 2.5-fold enrichment for rare CNVs comprising ovary-expressed genes, and genes implicated in autoimmune response and apoptotic signaling. Moreover, there was a higher prevalence of deletions encompassing genes that escape X inactivation, noncoding RNAs, and intergenic DNA sequences among POI females, highlighting structural differences between X chromosomes of fertile and POI females. Furthermore, we discovered a ~4% carrier incidence for X-linked disorders among fertile women.

CONCLUSION

We constructed a high-resolution map of female-specific CNVs that provides critical insights into the spectrum of human genetic variation, sex-specific disease risk factors, and reproductive potential. We discovered novel CNVs associated with ovarian dysfunction and support polygenic models for POI.

A 47,XXY Pregnant Woman without the SRY Gene

Individuals with a 47,XXY karyotype usually present with a male phenotype due to the additional Y chromosome. In this paper, we describe a 47,XXY female who was pregnant with a fetus of the same karyotype based on chromosome analysis of amniotic fluid cells. Further analysis of her Y chromosome indicated that the additional Y chromosome contains no SRY gene on the short arm but carries the azoospermia factor region on the long arm, including azoospermia factor a, b and c (AZFa, AZFb, AZFc). This region may influence her female phenotype. Fertile females with a 47,XXY karyotype and loss of SRY are extremely rare. This paper is the first report of a 47,XXY pregnant woman with a normal phenotype and may enrich our knowledge on 47,XXY individuals.

Next Generation Sequencing (NGS) in chromosome translocation 46, XX, t (9; X) (q22; q28) - a case report

This paper reports the case of a patient who sought assisted reproductive technology (ART) treatment and was referred to pre-implantation genetic diagnosis (PGD) on account of a chromosomal translocation presented with secondary infertility. The patient underwent a highly complex ART treatment and had 14 metaphase II oocytes collected on the day of follicular aspiration. The embryos were taken to extended culture and five were biopsied and vitrified. The embryo genetic report showed aneuploidy in four of the blastocysts, while the other resulted in 46, XX. In conclusion, chromosome translocations involving the X chromosome might result in the deregulation of gene expression and defective ovarian formation. Therefore, the genes present in the X chromosome are believed to be essential in normal ovarian function.

Mild phenotypes associated with an unbalanced X-autosome translocation, 46,X,der(X)t(X;8)(q28;q13)

Unbalanced X-autosome translocation can result in various phenotypic manifestations. We present the first case of 46,X,der(X)t(X;8)(q28;q13) in a 34-year-old female with relatively mild manifestations, including congenital heart disease, epicanthal fold, mild intellectual disability, and menstrual irregularity. Our findings expand the known spectrum of unbalanced X-autosome translocations, for improved clinical management.

[Usefulness of CGH-array and SNP-array for the etiological diagnosis of premature ovarian insufficiency]

Premature ovarian insufficiency (POI) defined by the cessation of ovarian function before the age of 40 years and the increase of gonadotropins (> 25 UI/l) occurs in approximately 1-5% of women. Different mechanisms are responsible for POI: chemotherapy, radiotherapy, environmental factors or genetic causes but most frequently no cause is identified. In order to determine the etiology of POI, cytogenetic analyses such as karyotype are performed. The karyotype allows to identify abnormalities of the number of chromosomes as well as abnormalities of the structure such as translocations, deletions or insertions of a size greater than 5-10 Mb… Turner syndrome is the most frequent genetic cause of POI and deletions of the long arm of the X chromosome are other causes of POI identified by the karyotype. However, the resolution of the karyotype is low and other cytogenetic techniques were developed such as all genome microarray analysis. This technique includes CGH-array and SNP-array and allows to identify gain or loss of chromosomal material as small as 10 kb but not the balanced structural rearrangements. Different studies using microarray analysis in cohorts of patients presenting with POI identify candidate genes responsible for POI. Furthermore, they allowed to identify a recurrent microdeletion, which includes the CPEB1 gene, located in 15q25.2 in about 1.5% of patients with POI.

Emmenagogue properties of Milicia excelsa (Welw.) C.C. Berg (Moraceae) based, at least in part, on its ability to correlate the activity of the hypothalamic-pituitary axis to that of the ovaries

ETHNOPHARMACOLOGICAL RELEVANCE

Milicia excelsa (Welw.) C.C. Berg (Moraceae) is a medicinal plant recommended over tropical Africa as a cure for several ailments including amenorrhea. This is the hallmark of an ovarian lesion or a dysfunction of the hypothalamic-pituitary-ovarian axis which may lead to infertility, osteoporosis or endometrial cancer. However, regardless these traditional claims, no scientific report dealing with emmenagogue properties has been reported yet.

AIM OF THE STUDY

To bring scientific evidence to the curative action of the plant, we proposed evaluating the effects of a root aqueous extract of Milicia excelsa on female Wistar rat sexual maturation.

MATERIAL AND METHODS

The study was performed in immature (45 days old) female Wistar rats orally treated with the root aqueous extract of Milicia excelsa at doses of 14, 77 and 140mg/kg BW/day for 7 and 15 consecutive days. Genistein (10mg/kg BW) served as the reference substance. Negative control animals, treated with the vehicle, were followed up for 7, 15, 30 and 45 days and rats were aged 52, 60, 75 and 90 days at these respective days. This allowed setting the nubile age of experimental animals and to determine the impact of treatments with genistein or the aqueous extract of Milicia excelsa on the age of rat sexual maturation. Since female rats do not have menstruation and that the normal menstrual cycle occurs because of changing levels of hormones made and secreted by the ovaries in response to hormonal signals from the pituitary gland, the effects of treatments were evaluated on the pituitary production of gonadotropins, the ovarian production of estradiol and progesterone, and uterine and vaginal growths.

RESULTS

The sexual maturation of untreated rats was set at 90 days old. This sexual maturation was indicated by the simultaneous elevation of gonadotropins (FSH and LH (p<0.01)) and ovarian hormones (estradiol (p<0.001) and progesterone (p<0.05)) in animals aged 90 days. Uterine and vaginal growths (p < 0.001) observed in these animals appear as the result of elevated level of estradiol. The root aqueous extract of Milicia excelsa displayed genistein-like effects and increased FSH and estradiol serum levels following both treatment periods (7 and 15 days). Estradiol serum concentration significantly increased following a 7-day treatment at the dose of 14mg/kg BW (p<0.001). This resulted in an increase in the uterine wet weight, uterine and vaginal epithelial heights (p<0.05). These results suggest that the root aqueous extract of Milicia excelsa reduced rats' sexual maturation from 90 to 52 days. Moreover, animals' body weight was not affected following treatment with Milicia excelsa.

CONCLUSION

The root aqueous extract of Milicia excelsa may solve the problem of amenorrhea by synchronizing the activity of the hypothalamic-pituitary axis to the ovarian production of estradiol and progesterone. The unaltered body weight following treatments justifies at least in part, the traditional use of Milicia excelsa for primary and secondary amenorrhea.

Primary ovarian insufficiency with t(5;13): a case report and literature review on disrupted genes

OBJECTIVES

To report a woman with primary ovarian insufficiency (POI) with reciprocal translocation between chromosomes 5 and 13.

METHODS

Chromosomal analysis (G-banding) of a 39-year-old woman with elevated gonadotropin levels and secondary amenorrhea and review of the literature with a special focus on disrupted genes at the reported breakpoints.

RESULTS

A reciprocal translocation between the long arms of chromosomes 5 and 13 was identified in the patient (46,XX,t(5;13)(q13;q14)). Investigation of the breakpoints revealed that the 13q14.1 region encompasses FOXO1 (forkhead box 1) gene, which has an important role in granulosa cell function and follicle maturation.

CONCLUSIONS

Autosomal translocations are rare in women with POI. We have reported the first case of a de novo reciprocal translocation involving chromosomes 5 and 13 in a POI patient. As one of the breakpoints encompasses the FOXO1 gene, it seems that disruption of this gene can be the cause of POI in this patient. This provides further evidence on the role of autosomal translocations in disrupting POI-associated genes. Therefore, concentrating on the genes at the breakpoints will be helpful to delineate the new biological pathways or genes involved in POI pathogenesis.

A Rare Variant of Turner Syndrome in Four Sequential Generations: Effect of the Interplay of Growth Hormone Treatment and Estrogens on Body Proportion

BACKGROUND

Terminal Xp deletion leads to SHOX haploinsufficiency, and when it exceeds Xp22.33 it causes a variant of Turner syndrome (TS) in which gonadal function is preserved and short stature constitutes the major clinical feature.

CASE REPORT

We present a family with vertical transmission of TS that affected six women in four sequential generations. The karyotype was defined as a combination of terminal Xp deletion and terminal Xq duplication: 46,X,rec(X)inv(p21.1q27.3). All affected women had short stature, but had developed spontaneous puberty and normal fertility. Generation IV exclusively received recombinant human growth hormone (rhGH). We investigated the effect of rhGH treatment on skeletal growth and body proportion via the comparison of auxological data from an untreated 39.7-year-old mother to her 14.8-year-old rhGH-treated daughter. The adult height of the daughter was substantially better than that of the mother [160.3 cm (-0.8 SDS) and 150.0 cm (-2.7 SDS), respectively]; however, the disproportion progressed following rhGH treatment and ultimately led to a worse trunk-to-extremities ratio compared with the mother (4.8 and 3.7 SDS, respectively).

CONCLUSION

This rare family confirms the vertical transmission of TS spanning multiple generations. The combination of endogenous estrogen production and exogenous rhGH administration in women with SHOX haploinsufficiency may worsen their body disproportion.

Disorganization of the germ cell pool leads to primary ovarian insufficiency

The mammalian ovary is an organ that controls female germ cell development, storing them and releasing mature oocytes for transporting to the oviduct. During the fetal stage, female germ cells change from a proliferative state to meiosis before forming follicles with the potential for the growth of surrounding somatic cells. Understanding of molecular and physiological bases of germ cell development in the fetal ovary contributed not only to the elucidation of genetic disorders in primary ovarian insufficiency (POI), but also to the advancement of novel treatments for patients with POI. Accumulating evidence indicates that mutations in NOBOX, DAZL and FIGLAgenes are associated with POI. In addition, cell biology studies revealed the important roles of these genes as essential translational factors for germ cell development. Recent insights into the role of the PI3K (phosphatidylinositol 3-kinase)-Akt signaling pathway in primordial follicle activation allowed the development of a new infertility treatment, IVA (in vitro activation), leading to successful pregnancy/delivery in POI patients. Furthermore, elucidation of genetic dynamics underlying female germ cell development could allow regeneration of oocytes from ES (embryonic stem)/iPS (induced pluripotent stem) cells in mammals. The purpose of this review is to summarize basic findings related to female germ cell development and potential clinical implications, especially focusing on POI etiologies. We also summarize evolving new POI therapies based on IVA as well as oocyte regeneration.

Cognitive changes across the menopause transition: A longitudinal evaluation of the impact of age and ovarian status on spatial memory

Cognitive changes that occur during mid-life and beyond are linked to both aging and the menopause transition. Studies in women suggest that the age at menopause onset can impact cognitive status later in life; yet, little is known about memory changes that occur during the transitional period to the postmenopausal state. The 4-vinylcyclohexene diepoxide (VCD) model simulates transitional menopause in rodents by depleting the immature ovarian follicle reserve and allowing animals to retain their follicle-deplete ovarian tissue, resulting in a profile similar to the majority of perimenopausal women. Here, Vehicle or VCD treatment was administered to ovary-intact adult and middle-aged Fischer-344 rats to assess the trajectory of cognitive change across time with normal aging and aging with transitional menopause via VCD-induced follicular depletion, as well as to evaluate whether age at the onset of follicular depletion plays a role in cognitive outcomes. Animals experiencing the onset of menopause at a younger age exhibited impaired spatial memory early in the transition to a follicle-deplete state. Additionally, at the mid- and post- follicular depletion time points, VCD-induced follicular depletion amplified an age effect on memory. Overall, these findings suggest that age at the onset of menopause is a critical parameter to consider when evaluating learning and memory across the transition to reproductive senescence. From a translational perspective, this study illustrates how age at menopause onset might impact cognition in menopausal women, and provides insight into time points to explore for the window of opportunity for hormone therapy during the menopause transition period. Hormone therapy during this critical juncture might be especially efficacious at attenuating age- and menopause- related cognitive decline, producing healthy brain aging profiles in women who retain their ovaries throughout their lifespan.

Premature Ovarian Insufficiency: New Perspectives on Genetic Cause and Phenotypic Spectrum

Premature ovarian insufficiency (POI) is one form of female infertility, defined by loss of ovarian activity before the age of 40 and characterized by amenorrhea (primary or secondary) with raised gonadotropins and low estradiol. POI affects up to one in 100 females, including one in 1000 before the age of 30. Substantial evidence suggests a genetic basis for POI; however, the majority of cases remain unexplained, indicating that genes likely to be associated with this condition are yet to be discovered. This review discusses the current knowledge of the genetic basis of POI. We highlight genes typically known to cause syndromic POI that can be responsible for isolated POI. The role of mouse models in understanding POI pathogenesis is discussed, and a thorough list of candidate POI genes is provided. Identifying a genetic basis for POI has multiple advantages, such as enabling the identification of presymptomatic family members who can be offered counseling and cryopreservation of eggs before depletion, enabling personalized treatment based on the cause of an individual's condition, and providing better understanding of disease mechanisms that ultimately aid the development of improved treatments.

Intrauterine death in singleton pregnancies with trisomy 21, 18, 13 and monosomy X

Summary A retrospective study from November 2004 to May 2012, conducted at the Obstetric Clinic of Hospital das Clínicas, Faculdade de Medicina, Universidade de São Paulo (HC-FMUSP), which included 92 singleton pregnancies with prenatal diagnosis of trisomy of chromosome 21 (T21), 18, 13 (T13/18) and monosomy X (45X), with diagnosis performed until the 26th week of pregnancy. The aim of the study was to describe the frequency and to investigate predictors of spontaneous fetal death (FD). Diagnosis (T21, n=36; T13/18, n=25; 45X, n=31) was made at a mean gestational age of 18.3±3.7 weeks, through chorionic villus biopsy (n=22,24%), amniocentesis (n=66, 72%) and cordocentesis (n=4, 4%). Major malformations were present in 45 (49%); with hydrops in 32 (35%) fetuses, more frequently in 45X [n=24/31, 77% vs. T21 (n=6/36, 17%) and T13/18 (n=2/25, 8%), p<0.001]. Specialized fetal echocardiography was performed in 60% (55/92). Of these, 60% (33/55) showed changes in heart morphology and/or function. Fetuses with T13/18 had a higher incidence of cardiac anomalies [60 vs. 25% (T21) and 29% (45X), p= 0.01]. FD occurred in 55 (60%) gestations, being more frequent in 45X [n=26/31, 84% vs. T21 (n=13/36, 36%) and T13/18 (n=16/25, 64%), p<0.01]. Stepwise analysis showed a correlation between hydrops and death in fetuses with T21 (LR= 4.29; 95CI=1.9-8.0, p<0.0001). In fetuses with 45X, the presence of echocardiographic abnormalities was associated with lower risk of FD (LR= 0.56; 95CI=0.27- 0.85, p=0.005). No predictive factors were identified in the T13/18 group. Intra- uterine lethality of aneuploid fetuses is high. Occurrence of hydrops increases risk of FD in pregnancies with T21. In pregnancies with 45X, the occurrence of echocardiographic changes reduces this risk.

Human Umbilical Cord Mesenchymal Stem Cells Therapy in Cyclophosphamide-Induced Premature Ovarian Failure Rat Model

Premature ovarian failure (POF) is one of the most common causes of infertility in women. In our present study, we established cyclophosphamide- (CTX-) induced POF rat model and elucidated its effect on ovarian function. We detected the serum estrogen, follicle stimulating hormone, and anti-Müllerian hormone of mice models by ELISA and evaluated their folliculogenesis by histopathology examination. Our study revealed that CTX administration could severely disturb hormone secretion and influence folliculogenesis in rat. This study also detected ovarian cells apoptosis by deoxy-UTP-digoxigenin nick end labeling (TUNEL) and demonstrated marked ovarian cells apoptosis in rat models following CTX administration. In order to explore the potential of human umbilical cord mesenchymal stem cells (UCMSCs) in POF treatment, the above indexes were used to evaluate ovarian function. We found that human UCMSCs transplantation recovered disturbed hormone secretion and folliculogenesis in POF rat, in addition to reduced ovarian cell apoptosis. We also tracked transplanted UCMSCs in ovaries by fluorescence in situ hybridization (FISH). The results manifested that the transplanted human UCMSCs could reside in ovarian tissues and could survive for a comparatively long time without obvious proliferation. Our present study provides new insights into the great clinical potential of human UCMSCs in POF treatment.

A unique mosaic Turner syndrome patient with androgen receptor gene derived marker chromosome

Patients with Turner syndrome are generally characterized by having short stature with no secondary sexual characteristics. Some abnormalities, such as webbed neck, renal malformations (>50%) and cardiac defects (10%) are less common. The intelligence of these patients is considered normal. Non-mosaic monosomy X is observed in approximately 45% of postnatal patients with Turner syndrome and the rest of the patients have structural abnormalities or mosaicism involving 46,X,i(Xq), 45,X/46,XX, 45,X and other variants. The phenotype of 45,X/46,X,+mar individuals varies by the genetic continent and degree of the mosaicism. The gene content of the marker chromosome is the most important when correlating the phenotype with the genotype. Here we present an 11-year-old female who was referred for evaluation of her short stature and learning disabilities. Conventional cytogenetic investigation showed a mosaic 45,X/46,X,+mar karyotype. Fluorescence in situ hybridization showed that the marker chromosome originated from the X chromosome within the androgen receptor (AR) and X-inactive specific transcript (XIST) genes. Therefore, it is possible that aberrant activation of the marker chromosome, compromising the AR and XIST genes, may modify the Turner syndrome phenotype.

Structural Variant Detection by Large-scale Sequencing Reveals New Evolutionary Evidence on Breed Divergence between Chinese and European Pigs

In this study, we performed a genome-wide SV detection among the genomes of thirteen pigs from diverse Chinese and European originated breeds by next genetation sequencing, and constrcuted a single-nucleotide resolution map involving 56,930 putative SVs. We firstly identified a SV hotspot spanning 35 Mb region on the X chromosome specifically in the genomes of Chinese originated individuals. Further scrutinizing this region by large-scale sequencing data of extra 111 individuals, we obtained the confirmatory evidence on our initial finding. Moreover, thirty five SV-related genes within the hotspot region, being of importance for reproduction ability, rendered significant different evolution rates between Chinese and European originated breeds. The SV hotspot identified herein offers a novel evidence for assessing phylogenetic relationships, as well as likely explains the genetic difference of corresponding phenotypes and features, among Chinese and European pig breeds. Furthermore, we employed various SVs to infer genetic structure of individuls surveyed. We found SVs can clearly detect the difference of genetic background among individuals. This clues us that genome-wide SVs can capture majority of geneic variation and be applied into cladistic analyses. Characterizing whole genome SVs demonstrated that SVs are significantly enriched/depleted with various genomic features.

Premature ovarian failure: clinical presentation and treatment

Premature ovarian failure is a devastating diagnosis for reproductive-aged women. The diagnosis is relatively easy. However, it has serious health consequences, including psychological distress, infertility, osteoporosis, autoimmune disorders, ischemic heart disease, and increased risk for mortality. Management should be initiated immediately to prevent long-term consequences. Estrogen therapy is the mainstay of management. Postmenopausal estrogen therapy studies should not be used to determine the risks of treatment in these young women.

Analysis of FMR1 gene premutation and X chromosome cytogenetic abnormalities in 100 Tunisian patients presenting premature ovarian failure

OBJECTIVE

To evaluate the prevalence of FMR1 premutations and X chromosome cytogenetic abnormalities in a large cohort of Tunisian women with premature ovarian failure (POF).

PATIENTS AND METHODS

The cohort consisted of 127 Tunisian women with POF referred by endocrinologists and gynecologists for genetic investigation in the context of idiopathic POF and altered hormonal profiles. Clinical information concerning the reproductive function in the family, previous hormonal measurements and/or possible fertility treatment were collected. Karyotype, FISH analyses, FMR1 and FMR2 testing were performed for all patients.

RESULTS

Fifteen patients (11.81%) presented structural or numerical X chromosomal abnormalities. Moreover, we detected in 12 patients (10.71%) a high level of X mosaicism. Analysis of FMR1 gene in the 100 patients without X chromosomal abnormalities showed that five percent of the patients carried a FMR1 premutation allele. On the other hand, the FMR2 screening did not reveal any deletion.

CONCLUSION

Our study confirms the major role of X chromosome abnormalities in POF and highlights the importance of karyotype analyses and FMR1 screening. These investigations provide valuable information for diagnosis and genetic counseling for these women who still have a 5% chance of spontaneous conception.

Genetics of primary ovarian insufficiency: new developments and opportunities

BACKGROUND

Primary ovarian insufficiency (POI) is characterized by marked heterogeneity, but with a significant genetic contribution. Identifying exact causative genes has been challenging, with many discoveries not replicated. It is timely to take stock of the field, outlining the progress made, framing the controversies and anticipating future directions in elucidating the genetics of POI.

METHODS

A search for original articles published up to May 2015 was performed using PubMed and Google Scholar, identifying studies on the genetic etiology of POI. Studies were included if chromosomal analysis, candidate gene screening and a genome-wide study were conducted. Articles identified were restricted to English language full-text papers.

RESULTS

Chromosomal abnormalities have long been recognized as a frequent cause of POI, with a currently estimated prevalence of 10-13%. Using the traditional karyotype methodology, monosomy X, mosaicism, X chromosome deletions and rearrangements, X-autosome translocations, and isochromosomes have been detected. Based on candidate gene studies, single gene perturbations unequivocally having a deleterious effect in at least one population include Bone morphogenetic protein 15 (BMP15), Progesterone receptor membrane component 1 (PGRMC1), and Fragile X mental retardation 1 (FMR1) premutation on the X chromosome; Growth differentiation factor 9 (GDF9), Folliculogenesis specific bHLH transcription factor (FIGLA), Newborn ovary homeobox gene (NOBOX), Nuclear receptor subfamily 5, group A, member 1 (NR5A1) and Nanos homolog 3 (NANOS3) seem likely as well, but mostly being found in no more than 1-2% of a single population studied. Whole genome approaches have utilized genome-wide association studies (GWAS) to reveal loci not predicted on the basis of a candidate gene, but it remains difficult to locate causative genes and susceptible loci were not always replicated. Cytogenomic methods (array CGH) have identified other regions of interest but studies have not shown consistent results, the resolution of arrays has varied and replication is uncommon. Whole-exome sequencing in non-syndromic POI kindreds has only recently begun, revealing mutations in the Stromal antigen 3 (STAG3), Synaptonemal complex central element 1 (SYCE1), minichromosome maintenance complex component 8 and 9 (MCM8, MCM9) and ATP-dependent DNA helicase homolog (HFM1) genes. Given the slow progress in candidate-gene analysis and relatively small sample sizes available for GWAS, family-based whole exome and whole genome sequencing appear to be the most promising approaches for detecting potential genes responsible for POI.

CONCLUSION

Taken together, the cytogenetic, cytogenomic (array CGH) and exome sequencing approaches have revealed a genetic causation in ∼20-25% of POI cases. Uncovering the remainder of the causative genes will be facilitated not only by whole genome approaches involving larger cohorts in multiple populations but also incorporating environmental exposures and exploring signaling pathways in intragenic and intergenic regions that point to perturbations in regulatory genes and networks.

Perspectives in Pediatric Pathology, Chapter 5. Gonadal Dysgenesis

One of the most challenging areas in pediatric testicular pathology is the appropriate understanding and pathological diagnosis of disorders of sexual development (DSD), and in particular, the issue of gonadal dysgenesis. Here we present the main concepts necessary for their understanding and appropriate classification, with extensive genetic correlations.

A lentiviral vector visualizing the germ cell specification in vitro under the control of Figla promoter

Premature ovarian failure (POF) is affecting more and more women, which is the loss of function of the ovaries before age 40. To elucidate the underlying mechanisms of the oogenesis is of importance to understand the causes of impaired fertility and POF. However, mammalian oogenesis in vivo is a complex process. Thus, building an oogenesis visualizing system is beneficial for the study of oogenesis. In this study, we found that Figla is specifically expressed in female mice oocyte. Then, we constructed a lentiviral vector (pTRIP-Figla-EGFP-puro) under the control of Figla promoter, which drived enhanced green fluorescent protein (EGFP) as an indicator and used the lentiviral vector transduction the ovarian cells and induced germ cells derived from human umbilical cord mesenchymal stem cells (hUC-MSCs), and the results showed that the lentiviral vector we constructed was able to specifically express green fluorescent protein (GFP) in the ovarian oocyte and induced oocyte-like cells derived from hUC-MSCs, which was Figla-positive cells. These results suggest that pTRIP-Figla-EGFP vector provides a new system to study the role of Figla in oogenesis, and an approach to study the development and the differentiation of germ cells derived from stem cells.

Risks associated with premature ovarian failure in Han Chinese women

In this retrospective study, the relationship between demographic characteristics, past medical history, general lifestyle habits and susceptibility of premature ovarian failure (POF) in Han Chinese population was investigated. Five hundred and fifty-three patients with POF and 400 women with normal ovarian function were recruited. A questionnaire was designed to gather information from responders. Logistic regression was carried out to calculate odds ratios (OR), 95% confidence intervals (95% CI) and P-values. History of pelvic surgery, mumps, having relatives with menstrual abnormalities and exposure to chemical agents were significantly associated with increased risk of POF (OR 5.53 [2.15 to 14.23]; 3.26 [2.38 to 4.47]; 28.12 [8.84 to 89.46]; 4.47 [2.09 to 9.58]). Vegetarian diet, tea and mineral water consumption reduced the risk of POF (OR 0.27 [0.19 to 0.37]; 0.04 [0.03 to 0.07]; 0.63 [0.47 to 0.85], respectively). Heredity, pelvic surgery, mumps and exposure to chemical agents were identified as risk factors for POF, whereas vegetarian diet, tea consumption and mineral water drinking were protective. Therefore, genetic consultation could help those women whose relatives manifested an early or premature menopause to avoid the consequences of possible premature ovarian function cessation. Avoidance of exposure to endocrine disrupters and flavonoids intake should be considered.

Are FSHR polymorphisms risk factors to premature ovarian insufficiency?

Premature ovarian insufficiency (POI) is an ovarian dysfunction characterized by increased FSH levels and amenorrhea before 40 years old. In recent years, the search for genetic causes of POI intensified and studies have been published relating the presence of mutations and polymorphisms in genes associated with development, recruitment and oocyte atresia. The aim of this study was to evaluate the presence of FSHR polymorphisms in our population and contribute with the elucidation of POI etiology. To achieve it, we have studied 100 patients with POI (G1), 60 patients with border line levels of FSH (G2) and 123 controls with regular menopause onset. Cytogenetic analysis of patients' samples and genotyping of Asn680Ser and Ala307Thr polymorphisms were performed in cases and controls. Cytogenetic analysis showed that 92% of G1 patients had normal karyotype, 4% presented polymorphic variants, 3% presented mosaic karyotype involving X chromosome. In G2, 91.6% had normal karyotype results, 3.2% displayed polymorphic variants, and 3.3% presented a mosaic karyotype involving X chromosome. Statistical comparison showed that the polymorphic allele of Ala307Thr polymorphism is more frequent in patients than in controls (G1: p < 0.001 and G2: p = 0.0259). This association has not been previously reported. We concluded that Ala307Thr polymorphism in FSHR can be potentially associated to POI development and can be considered as a screening marker in patients with ovarian failure signals.

Genetics of female infertility due to anomalies of the ovary and mullerian ducts

Genetic factors are pivotal in reproductive development and subsequent reproductive processes. If disturbed, infertility can occur. In the female, genetic factors affecting the ovary and the uterus are not uncommon causes of infertility. Terminal deletions on the X long arm and X short arm and X chromosomal mosaicism have long been accepted as causes of premature ovarian failure (POF). Responsible genes on the X have not yet elucidated. Attractive candidate genes for POF also exist on autosomes, and in over a dozen genes molecular perturbations are documented in non-syndromic POF. The most common single-gene cause of POF is premutation carriers for FMR1 (fragile X syndrome). As other candidate genes and additional ethnic groups are interrogated, the proportion of POF cases due to single-gene mutation will increase. Among uterine anomalies, incomplete mullerian fusion is most common. Increased recurrence risks for first-degree relatives confirm a role for genetic factors; interrogation of candidate genes is under way.

Turner syndrome masquerading as normal early puberty

Approximately 50% of patients with Turner syndrome (TS) have complete loss of one X chromosome, whereas the rest of the patients with TS display mosaicism or structural abnormalities of the X chromosome. Most well-known common features are short stature and gonadal failure. Approximately one third of girls with TS may enter spontaneous puberty, but only half those completed with menarche. However, some atypical features of TS have been described. Many studies have been conducted to verify and delineate proposed loci for genes pertaining to the TS phenotype, and correlations between karyotype and phenotype. A few rare cases of precocious puberty with TS have been described. Here we describe a case of TS with the Xp22.1 deletion presenting with short final stature, early normal onset of spontaneous puberty, and Graves' disease, without short stature during puberty.

Bilateral total ovarian hypoplasia in a Holstein Friesian heifer

A report of a female Holstein Friesian heifer with ovarian hypoplasia is presented. The heifer had normal female external genitalia, but showed neither estrus nor became pregnant after siring with a fertile bull. At necropsy the vagina, uterine body and uterine horns appeared normal. Bilateral streak structures surrounded by mesovarium were observed and dissected for further investigation. Histological investigation revealed that a case of bilateral total ovarian hypoplasia was the cause of infertility. This is the first published report of ovarian hypoplasia from Antalya province in Turkey.

Analysis of progesterone receptor membrane component 1 mutation in Han Chinese women with premature ovarian failure

The gene PGRMC1 is highly expressed in the granulose and luteal cells of rodent and primate ovaries. Its role in anti-apoptosis and regulating cell-cycle progression suggests a role in regulating follicle growth. The hypothesis is supported by the study in mice and studies in Sweden. In this study, the coding exons of PGRMC1 were sequenced among 196 Chinese women with premature ovarian failure (POF) and 200 controls, and one novel missense mutation was identified (C.556C>T, p. Pro186Ser) in the POF group and one novel SNP (C.533C>T, p. Trh177Ile) was identified in both groups. The mutation is not considered causative because protein prediction did not indicate a deleterious effect. It is concluded that coding mutations of PGRMC1 do not seem to be a common cause of the disease in Han Chinese women. Future studies in larger cohorts from other ethnic groups are necessary to establish the role of PGRMC1 in POF.

Identification of a duplication within the GDF9 gene and novel candidate genes for primary ovarian insufficiency (POI) by a customized high-resolution array comparative genomic hybridization platform

STUDY QUESTION

Can high-resolution array comparative genomic hybridization (CGH) analysis of DNA samples from women with primary ovarian insufficiency (POI) improve the diagnosis of the condition and identify novel candidate genes for POI?

SUMMARY ANSWER

A mutation affecting the regulatory region of growth differentiation factor 9 (GDF9) was identified for the first time together with several novel candidate genes for POI.

WHAT IS KNOWN ALREADY

Most patients with POI do not receive a molecular diagnosis despite a significant genetic component in the pathogenesis.

STUDY DESIGN, SIZE, DURATION

We performed a case–control study. Twenty-six patients were analyzed by array CGH for identification of copy number variants. Novel changes were investigated in 95 controls and in a separate population of 28 additional patients with POI. The experimental procedures were performed during a 1-year period.

PARTICIPANTS/MATERIALS, SETTING, METHODS

DNA samples from 26 patients with POI were analyzed by a customized 1M array-CGH platform with whole genome coverage and probe enrichment targeting 78 genes in sex development. By PCR amplification and sequencing, the breakpoint of an identified partial GDF9 gene duplication was characterized. A multiplex ligation-dependent probe amplification (MLPA) probe set for specific identification of deletions/duplications affecting GDF9 was developed. An MLPA probe set for the identification of additional cases or controls carrying novel candidate regions identified by array-CGH was developed. Sequencing of three candidate genes was performed.

MAIN RESULTS AND THE ROLE OF CHANCE

Eleven unique copy number changes were identified in a total of 11 patients, including a tandem duplication of 475 bp, containing part of the GDF9 gene promoter region. The duplicated region contains three NOBOX-binding elements and an E-box, important for GDF9 gene regulation. This aberration is likely causative of POI. Fifty-four patients were investigated for copy number changes within GDF9, but no additional cases were found. Ten aberrations constituting novel candidate regions were detected, including a second DNAH6 deletion in a patient with POI. Other identified candidate genes were TSPYL6, SMARCC1, CSPG5 and ZFR2.

LIMITATIONS, REASONS FOR CAUTION

This is a descriptive study and no functional experiments were performed.

WIDER IMPLICATIONS OF THE FINDINGS

The study illustrates the importance of analyzing small copy number changes in addition to sequence alterations in the genetic investigation of patients with POI. Also, promoter regions should be included in the investigation.

STUDY FUNDING/COMPETING INTEREST(S)

The study was supported by grants from the Swedish Research council (project no 12198 to A.W. and project no 20324 to A.L.H.), Stockholm County Council (E.I., A.W. and K.R.W.), Foundation Frimurare Barnhuset (A.N., A.W. and M.B.), Karolinska Institutet (A.N., A.L.H., E.I., A.W. and M.B.), Novo Nordic Foundation (A.W.) and Svenska Läkaresällskapet (M.B.). The funding sources had no involvement in the design or analysis of the study. The authors have no competing interests to declare.

TRIAL REGISTRATION NUMBER

Not applicable.

Causes of amenorrhea in Korea: Experience of a single large center

Objective

To investigate the causes of amenorrhea in Korean women.

Methods

Medical records from 1,212 women with amenorrhea who visited the Department of Obstetrics and Gynecology, Asan Medical Center, between January 1989 and December 2011 were retrospectively reviewed. Amenorrhea was categorized as either primary or secondary.

Results

Primary amenorrhea was identified in 132 of the patients (10.9%) and secondary amenorrhea in 1,080 (89.1%). The most frequent causes of primary amenorrhea were gonadal dysgenesis (28.0%, 37/132); Mayer-Rokitansky-Küster-Hauser syndrome (20.0%, 27/132); and constitutional delay and androgen insensitivity syndrome (8.3%, 11/132; 8.3%, 11/132, respectively). Secondary amenorrhea was due to polycystic ovary syndrome (48.4%, 523/1,080); premature ovarian insufficiency (14.0%, 151/1,080); and nutrition-related hypogonadotropic hypogonadism (8.3%, 90/1,080).

Conclusion

In this retrospective study, gonadal dysgenesis was the most common cause of primary amenorrhea and polycystic ovary syndrome was the most common cause of secondary amenorrhea in Korean women.

Primary ovarian insufficiency: an update

Primary ovarian insufficiency is a condition that represents impaired ovarian function on a continuum with intermittent ovulation. This condition commonly leads to premature menopause, defined as cessation of ovulation prior to the age of 40 years. Because there are potential immediate and long-term consequences of hypoestrogenism, a timely diagnosis is invaluable. This comprehensive review will discuss identifiable causes for primary ovarian insufficiency, including genetic disorders and metabolic abnormalities, as well as review current strategies for diagnosis, evaluation, and management of women with this condition.

No mutations in the PSMC3IP gene identified in a Swedish cohort of women with primary ovarian insufficiency

Ovarian dysfunction before the age of 40 years, characterized by hypergonadotropic hypogonadism and presenting with either primary or secondary amenorrhea, is called primary ovarian insufficiency (POI). POI has a significant genetic component, but the specific genetic cause is often unknown. A novel candidate gene for POI, PSMC3IP, has recently been identified. The aim of this study was to investigate a group of patients with POI for possible PSMC3IP mutations. Therefore, DNA samples from 50 patients with POI of primarily Swedish origin were used in the study, 27 with secondary amenorrhea (median age of diagnosis 23 years) and 23 with primary amenorrhea. Control material consisting of DNA samples from 95 women without POI was used for investigation of novel sequence variants. All exons and intron/exon boundaries of the PSMC3IP gene were analyzed by PCR and sequencing. As a result, no pathogenic mutation in the PSMC3IP gene was detected in the cohort. A previously unreported variant, NM_016556.3:c.337+33A>G, was detected in heterozygous form in 1 patient with secondary amenorrhea, likely constituting a normal variant. Two reported single nucleotide polymorphisms were detected in the cohort at the expected frequency. In conclusion, PSMC3IP gene mutations are not common causes of POI in this Swedish cohort.

The Genetics of Infertility: Current Status of the Field

Infertility is a relatively common health condition, affecting nearly 7% of all couples. Clinically, it is a highly heterogeneous pathology with a complex etiology that includes environmental and genetic factors. It has been estimated that nearly 50% of infertility cases are due to genetic defects. Hundreds of studies with animal knockout models convincingly showed infertility to be caused by gene defects, single or multiple. However, despite enormous efforts, progress in translating basic research findings into clinical studies has been challenging. The genetic causes remain unexplained for the vast majority of male or female infertility patients. A particular difficulty is the huge number of candidate genes to be studied; there are more than 2,300 genes expressed in the testis alone, and hundreds of those genes influence reproductive function in humans and could contribute to male infertility. At present, there are only a handful of genes or genetic defects that have been shown to cause, or to be strongly associated with, primary infertility. Yet, with completion of the human genome and progress in personalized medicine, the situation is rapidly changing. Indeed, there are 10-15 new gene tests, on average, being added to the clinical genetic testing list annually.

Genomic markers of ovarian reserve

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

Mutational analysis of SKP2 and P27 in Chinese Han women with premature ovarian failure

P27 and SKP2, a major regulator of P27, play a crucial role in ovarian function in mice. Both P27-deficient and SKP2-deficient female mice develop premature ovarian failure (POF). The coding regions of SKP2 and P27 were examined in 200 Chinese women with POF and 200 control volunteers. This study is the first to investigate SKP2 in POF. No plausible pathogenic mutations were detected. The results suggest that mutations in SKP2 and P27 are not common in Chinese Han women with POF.

The androgen receptor in health and disease

Androgens play pivotal roles in the regulation of male development and physiological processes, particularly in the male reproductive system. Most biological effects of androgens are mediated by the action of nuclear androgen receptor (AR). AR acts as a master regulator of downstream androgen-dependent signaling pathway networks. This ligand-dependent transcriptional factor modulates gene expression through the recruitment of various coregulator complexes, the induction of chromatin reorganization, and epigenetic histone modifications at target genomic loci. Dysregulation of androgen/AR signaling perturbs normal reproductive development and accounts for a wide range of pathological conditions such as androgen-insensitive syndrome, prostate cancer, and spinal bulbar muscular atrophy. In this review we summarize recent advances in understanding of the epigenetic mechanisms of AR action as well as newly recognized aspects of AR-mediated androgen signaling in both men and women. In addition, we offer a perspective on the use of animal genetic model systems aimed at eventually developing novel therapeutic AR ligands.

Mutations in DMC1 are not responsible for premature ovarian failure in Chinese women

The coding region of the disrupted meiotic cDNA gene (DMC1) was examined in 192 Chinese women with premature ovarian failure. Two known single-nucleotide polymorphisms, c.8632C>T in intron 4 and c.32377G>C in intron 10, were identified. The results suggest that mutations in the coding sequence of DMC1 are not associated with premature ovarian failure in Chinese women. The coding region of the disrupted meiotic cDNA gene (DMC1) was examined in 192 Chinese women with premature ovarian failure. Premature ovarian failure is defined as secondary amenorrhoea, infertility, oestrogen deficiency, and elevated gonadotrophin concentration in women younger than 40 years. DMC1 is a meiosis-specific gene, encoding a protein essential for meiotic homologous recombination. It participates in the formation of synaptonemal complexes and repair of double-strand breaks at recombination hotspots. Two known single-nucleotide polymorphisms, c.8632C>T in intron 4 and c.32377G>C in intron 10, were identified. No additional single-nucleotide polymorphisms or mutations were found. The results suggested mutations in the coding sequence of DMC1 are not associated with premature ovarian failure in Chinese women.

Patterns of molecular evolution of an avian neo-sex chromosome

Newer parts of sex chromosomes, neo-sex chromosomes, offer unique possibilities for studying gene degeneration and sequence evolution in response to loss of recombination and population size decrease. We have recently described a neo-sex chromosome system in Sylvioidea passerines that has resulted from a fusion between the first half (10 Mb) of chromosome 4a and the ancestral sex chromosomes. In this study, we report the results of molecular analyses of neo-Z and neo-W gametologs and intronic parts of neo-Z and autosomal genes on the second half of chromosome 4a in three species within different Sylvioidea lineages (Acrocephalidea, Timaliidae, and Alaudidae). In line with hypotheses of neo-sex chromosome evolution, we observe 1) lower genetic diversity of neo-Z genes compared with autosomal genes, 2) moderate synonymous and weak nonsynonymous sequence divergence between neo-Z and neo-W gametologs, and 3) lower GC content on neo-W than neo-Z gametologs. Phylogenetic reconstruction of eight neo-Z and neo-W gametologs suggests that recombination continued after the split of Alaudidae from the rest of the Sylvioidea lineages (i.e., after ~42.2 Ma) and with some exceptions also after the split of Acrocephalidea and Timaliidae (i.e., after ~39.4 Ma). The Sylvioidea neo-sex chromosome shares classical evolutionary features with the ancestral sex chromosomes but, as expected from its more recent origin, shows weaker divergence between gametologs.

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.

Detection of chromosome x;18 breakpoints and translocation of the xq22.3;18q23 regions resulting in variable fertility phenotypes

We describe a familial pattern of gonosomal-autosomal translocation between the X and 18 chromosomes, balanced and unbalanced forms, in male and female siblings. The proposita was consulted for hypergonadotropic hypogonadism. Karyotype analysis revealed a balanced 46, X, t(X;18)(q22.3;q23) genotype. The sister of the proband presented with oligomenorrhea with irregular menses and possesses an unbalanced form of the translocation 46, X, der(X), t(X;18)(q22.3;q23). The brother of the proband was investigated and was found to possess the balanced form of the same translocation, resulting in disrupted spermatogenesis. Maternal investigation revealed the progenitor karyotype 46, X, t(X;18)(q22.3;q23). Maternal inheritance and various genomic events contributed to the resultant genotypes. Primary infertility was initially diagnosed in all progeny; however, the male individual recently fathered twins. We briefly review the mechanisms associated with X;18 translocations and describe a pattern of inheritance, where breakpoints and translocation of the Xq22.3;18q23 regions have resulted in variable fertility.