Project description:Primary ovarian insufficiency (POI) is defined by the loss or dysfunction of ovarian follicles associated with amenorrhea before the age of 40. Symptoms include hot flashes, sleep disturbances, and depression, as well as reduced fertility and increased long-term risk of cardiovascular disease. POI occurs in ∼1% to 2% of women, although the etiology of most cases remains unexplained. Approximately 10% to 20% of POI cases are due to mutations in a single gene or a chromosomal abnormality, which has provided considerable molecular insight into the biological underpinnings of POI. Many of the genes for which mutations have been associated with POI, either isolated or syndromic cases, function within mitochondria, including MRPS22, POLG, TWNK, LARS2, HARS2, AARS2, CLPP, and LRPPRC. Collectively, these genes play roles in mitochondrial DNA replication, gene expression, and protein synthesis and degradation. Although mutations in these genes clearly implicate mitochondrial dysfunction in rare cases of POI, data are scant as to whether these genes in particular, and mitochondrial dysfunction in general, contribute to most POI cases that lack a known etiology. Further studies are needed to better elucidate the contribution of mitochondria to POI and determine whether there is a common molecular defect in mitochondrial function that distinguishes mitochondria-related genes that when mutated cause POI vs those that do not. Nonetheless, the clear implication of mitochondrial dysfunction in POI suggests that manipulation of mitochondrial function represents an important therapeutic target for the treatment or prevention of POI.
Project description:Primary ovarian insufficiency (POI) is an uncommon yet devastating occurrence that results from a premature depletion of the ovarian pool of primordial follicles. Our understanding of both putative and plausible mechanisms underlying POI, previously considered to be largely "idiopathic", has been furthered over the past several years, largely due to advances in the field of genetics and through expansion of translational models for experimental research. In this review, our goal is to familiarize the multidisciplinary readers of the F1000 platform with the strides made in the field of reproductive medicine that hold both preventative and therapeutic implications for those women who are at risk for or who have POI.
Project description:Primary ovarian insufficiency is one of the main causes of female infertility owing to an abnormal ovarian reserve. Its relevance has increased in more recent years due to the fact that age of motherhood is being delayed in developed countries, with the risk of having either primary ovarian insufficiency or less chances of pregnancy when women consider the option of having their first baby. Several exogenous factors can lead to this event, such us viral infections, metabolomic dysfunction, autoimmune diseases, and environmental or iatrogenic factors, although in most cases the mechanism that leads to the disorder is unknown. Genetic factors represent the most commonly identified cause and the impact of sex chromosome abnormalities (e.g., Turner syndrome or X structural abnormalities), autosomal and X-linked mutations on the genesis of primary ovarian insufficiency has also been well described. Yet in most cases, the genetic origin remains unknown and there are multiple candidate genes. This review aims to collect all the genetic abnormalities and genes associated with syndromic and non syndromic primary ovarian insufficiency that have been published in the literature to date using the candidate-gene approach and a genome-wide analysis.
Project description:Primary ovarian insufficiency (POI) is a genetically heterogeneous disorder that occurs in familial or sporadic fashion. Through whole exome sequencing in a Chinese pedigree with POI, we identified a novel homozygous missense mutation (ENST00000375755: c.1459G > T, p.D487Y) in the MSH5 gene in two sisters with POI. The homologous mutation in mice resulted in atrophic ovaries without oocytes, and in vitro functional study revealed that mutant MSH5 impaired DNA homologous recombination repair. From sanger sequencing of MSH5 in 200 sporadic POI patients, we identified three heterozygous mutations (ENST00000375755: c.1057C > A, p.L353M; c.1459G > T, p.D487Y and c.2107 A > G, p.I703V). Considering the heterozygous p.D487Y carrier in the POI pedigree was fertile, the causality of the three heterozygous mutations in POI need more evidence. Our studies confirmed that perturbation of genes involved in DNA damage repair could lead to non-syndromic POI. The underlying mechanism-inability to repair DNA damage-will receive increasing attention with respect to POI.
Project description:ContextPrimary ovarian insufficiency (POI) is a genetically heterogeneous condition associated with infertility and an increased risk of comorbidities. An increased number of genes implicated in DNA damage response pathways has been associated with POI as well as predisposition to cancers.ObjectiveWe sought to identify and characterize patients affected by POI caused by pathogenic variants in genes involved in DNA damage response during meiosis.SettingStudy subjects were recruited at academic centers.Patients or other participantsIndividuals with a diagnosis of POI and their family members were enrolled for genetic analysis. Clinical findings, family history, and peripheral blood samples were collected.Research designExome sequencing was performed on the study participants and their family members (when available). Protein conservation analysis and in silico modeling were used to obtain the structural model of the detected variants in the ZSWIM7 gene.Main outcome measure(s)Rare deleterious variants in known and candidate genes associated with POI.ResultsHomozygous deleterious variants in the ZSWIM7 gene were identified in 2 unrelated patients with amenorrhea, an absence of puberty, and prepubertal ovaries and uterus. Observed variants were shown to alter the ZSWIM7 DNA-binding region, possibly affecting its function.ConclusionsOur study highlights the pivotal role of the ZSWIM7 gene involved in DNA damage response during meiosis on ovarian development and function. Characterization of patients with defects in DNA repair genes has important diagnostic and prognostic consequences for clinical management and reproductive decisions.
Project description:ContextPrimary ovarian insufficiency (POI) is defined by menopause before 40 years of age. POI prevalence is higher among women with autoimmune Addison's disease (AAD) than in the general population, but their clinical characteristics are insufficiently studied.ObjectiveTo assess the prevalence of POI in a large cohort of women with AAD and describe clinical, immunological, and genetic characteristics.MethodsAn observational population-based cohort study of the Norwegian National Addison Registry. The Norwegian Prescription Database was used to assess prescription of menopausal hormone replacement therapy (HRT). A total of 461 women with AAD were studied. The primary outcome measure was prevalence of POI. Secondary outcomes were clinical characteristics, autoantibodies, and genome-wide single nucleotide polymorphism variation.ResultsThe prevalence of POI was 10.2% (47/461) and one-third developed POI before 30 years of age. POI preceded or coincided with AAD diagnosis in more than half of the women. The prevalence of concomitant autoimmune diseases was 72%, and AAD women with POI had more autoantibodies than AAD women without (≥2 autoantibodies in 78% vs 25%). Autoantibodies against side-chain cleavage enzyme (SCC) had the highest accuracy with a negative predictive value for POI of 96%. HRT use was high compared to the age adjusted normal population (11.3 % vs 0.7%).ConclusionOne in 10 women with AAD have POI. Autoantibodies against SCC are the most specific marker for autoimmune POI. We recommend testing women with AAD <40 years with menstrual disturbances or fertility concerns for autoantibodies against SCC.
Project description:Study questionWhat is the prevalence of somatic chromosomal instability among women with idiopathic primary ovarian insufficiency (POI)?Summary answerA subset of women with idiopathic POI may have functional impairment in DNA repair leading to chromosomal instability in their soma.What is known alreadyThe formation and repair of DNA double-strand breaks during meiotic recombination are fundamental processes of gametogenesis. Oocytes with compromised DNA integrity are susceptible to apoptosis which could trigger premature ovarian aging and accelerated wastage of the human follicle reserve. Genomewide association studies, as well as whole exome sequencing, have implicated multiple genes involved in DNA damage repair. However, the prevalence of defective DNA damage repair in the soma of women with POI is unknown.Study design, size, durationIn total, 46 women with POI and 15 family members were evaluated for excessive mitomycin-C (MMC)-induced chromosome breakage. Healthy fertile females (n = 20) and two lymphoblastoid cell lines served as negative and as positive controls, respectively.Participants/materials, setting, methodsWe performed a pilot functional study utilizing MMC to assess chromosomal instability in the peripheral blood of participants. A high-resolution array comparative genomic hybridization (aCGH) was performed on 16 POI patients to identify copy number variations (CNVs) for a set of 341 targeted genes implicated in DNA repair.Main results and the role of chanceArray CGH revealed three POI patients (3/16, 18.8%) with pathogenic CNVs. Excessive chromosomal breakage suggestive of a constitutional deficiency in DNA repair was detected in one POI patient with the 16p12.3 duplication. In two patients with negative chromosome breakage analysis, aCGH detected a Xq28 deletion comprising the Centrin EF-hand Protein 2 (CETN2) and HAUS Augmin Like Complex Subunit 7 (HAUS7) genes essential for meiotic DNA repair, and a duplication in the 3p22.2 region comprising a part of the ATPase domain of the MutL Homolog 1 (MLH1) gene.Limitations reasons for cautionPeripheral lymphocytes, used as a surrogate tissue to quantify induced chromosome damage, may not be representative of all the affected tissues. Another limitation pertains to the MMC assay which detects homologous repair pathway defects and does not test deficiencies in other DNA repair pathways.Wider implications of the findingsOur results provide evidence for functional impairment of DNA repair in idiopathic POI, which may predispose the patients to other DNA repair-related conditions such as accelerated aging and/or cancer susceptibility.Study funding/competing interest(s)Funding was provided by the National Institute of Child Health and Human Development. There were no competing interests to declare.
Project description:Primary ovarian insufficiency (POI), or premature ovarian failure, results from ovarian follicle depletion with a consequent elevation of FSH levels before age 40 years. We identified a family in which 9 women in 3 consecutive generations developed menopause at approximately age 30 years. We hypothesized a genetic cause with a dominant mode of inheritance.This was a family-based genetic study and a replicate group of women with POI.The study was conducted at an academic medical center.Seven affected women and an obligate carrier and 7 unaffected family members were genotyped. The genes of interest were also sequenced in 38 unrelated women with POI.The DNA from 7 family members was subjected to whole-exome sequencing. The genotypes of interest were confirmed and genotypes of additional family members and unrelated women with POI were determined using Sanger sequencing.A high-impact, deleterious variant that segregated appropriately with POI in the family was required.A heterozygous stop codon (Ser429X) was identified in the eukaryotic translation initiation factor 4E nuclear import factor 1 (eIF4ENIF1) in the proband and all affected women but not in the unaffected family members. The chance that such a high-impact, deleterious variant would segregate appropriately among the affected and unaffected relatives by chance is very low (P < .05). There were no additional mutations identified in eIF4ENIF1 or eIF4E in 38 unrelated women with POI.Data demonstrate a new gene associated with dominantly inherited POI. These results highlight the importance of translation initiation factors and their regulators in ovarian function.
Project description:BACKGROUND: Primary ovarian insufficiency (POI) is heterogeneous disease defined by amenorrhea or premature depletion of ovarian follicles before the age of 40 years. The etiology of POI is still unclear. The purpose of this study is to evaluate whether women with POI have an elevated serum levels of autoimmunologic parameters. METHODS: The serum from peripheral blood samples which come from 96 POI patients and 100 age-matched health women were analyzed for a series of autoimmune antibodies using protein microarray. The antibodies to double-stranded DNA (ds-DNA), histone (HIS), nuclear ribonucleoprotein (RNP), Sjogren's syndrome A (SSA/Ro), Sjogren's syndrome B (SSB/La) and Smith antigen, Jo-1, scleroderma-associated antigen (Scl-70) and centromere (CEN), zona pellucid (ZP), adrenocortical antibodies (ACA),Rheumatoid factor (RF), glomerular basement membrane (GBM), proliferating cell nuclear antigen (PCNA), myeloperoxidase (MPO), proteinase 3 (PR3), thyroid microsomal antibody and antinuclear antibody (ANA)were analyzed. RESULTS: Among the 96 women with POI and 100 age-matched health controls, women with POI had significantly elevated circulation levels of Jo-1 and PR3 (p = 0.010 and p = 0.001) whereas circulation levels of ANAs, dsDNA, histone, RNP, Sm, Scl-70, SSA, SSB, CEN, ZP, ACA, RF, GBM, PCNA, MPO and TM antibodies were similar between the two groups. CONCLUSIONS: This study shows that the autoimmune antibodies JO-1 and PR3 were significantly higher in POI women group which suggested that these antibodies may have played special role in POI, but the evaluation of the exact pathways of them remains to be determined.