The underlying cause for renal and uterine agenesis remains unknown in many cases, whereas recurrence in some families strongly suggests the involvement of genetic factors. Here, we identify 5 affected individuals from 3 families with phenotypes including bilateral or unilateral renal agenesis/hypoplasia, along with variable congenital uterine anomalies and costovertebral defects associated with heterozygous deleterious variants in NR6A1. The variant spectrum includes two inherited missense (c.1175T>G;p.(Met392Arg) and c.196C>T;p.(Arg66Cys)) as well as de novo loss of function, with the latter associated with a perinatal lethal phenotype characterized by bilateral renal agenesis. In vitro studies demonstrated partial loss-of-function for both missense variants. To investigate the role of NR6A1 in development, CRISPR-Cas9 zebrafish mutants for the orthologs nr6a1a and nr6a1b were generated. Mutants recapitulate the human phenotype, exhibiting impaired kidney development, including pronephros segmentation defects and adult kidney hypoplasia, along with axial skeletal abnormalities, cloacal anomalies, and disrupted anteroposterior expression of posterior hox genes. This study provides strong evidence linking NR6A1 heterozygous deleterious variants to renal, uterine and costovertebral defects in humans.
The PI3K/Akt pathway is thought to regulate key steps of mammalian oogenesis, such as dormant oocyte awakening during follicular activation, meiotic resumption and oocyte maturation. Supporting evidence is however indirect, as oocyte PI3K activation has never been formally demonstrated, and the PI3K isoforms involved have not been revealed. Here, we employed fluorescent PIP3 biosensors to characterize PI3K dynamics in mouse oocytes and we investigated the contribution of PI3K isoform p110α via conditional genetic ablation. Prophase oocytes showed baseline PI3K/Akt activation that could be further stimulated by adding Kit ligand (KitL). Contrary to previous reports, maternal PI3K proved dispensable for oocyte maturation in vitro, yet it was required for PIP3 synthesis in early embryos. We further show that oocyte p110α is not essential for oogenesis and female fertility. Accordingly, our data suggest that KitL activates isoform p110δ for PIP3 synthesis in oocytes. In contrast, constitutive PIP3 synthesis in early embryos is achieved by maternal p110α acting redundantly with p110δ. This study highlights the relevance of PIP3 biosensors in establishing the dynamics, mechanisms and roles of maternal PI3K signaling during mammalian oogenesis.
This study aims to explore the genetic anomalies (excluding aneuploidy) associated with Müllerian duct anomalies (MDA). This project is part of a large uterine transplantation (UTx) program, where women with MRKH (Mayer-Rokitansky-Küster-Hauser) syndrome are the primary candidates. The potential of the hereditary nature of MDA was evaluated to facilitate appropriate genetic counseling when applicable. We used chromosome microarray analysis (CMA) and exome sequencing (ES) to identify genetic variations that may contribute to the phenotype of MDA. A comprehensive description of the genital and extra-genital phenotype was established for each individual in whom a potentially relevant genetic variant has been identified. We analyzed data from 3 fetuses and 75 women with MDA. All individuals had CMA and 65 ES were analyzed. CMA identified 6 copy number variations (CNVs) of interest (diagnostic yield: 7.7
INTRODUCTION:Mayer-Rokitansky-Küster-Hauser (MRKH) syndrome with utero-vaginal aplasia is the most severe form of the Müllerian duct anomalies and can be associated with extra-genital abnormalities such as renal or skeletal anomalies, hearing loss, or cardiac defects. The past two decades have witnessed significant advances both in understanding the etiologies of MRKH and in the development of fertility treatments such as uterine transplantation. The present work aimed to determine the rate of women with MRKH syndrome who underwent optimal initial management (after comprehensive malformation assessment) and to establish the rate of patients eligible for uterine transplantation (i.e., those with a vaginal length ≥7 cm without reconstruction using a bowel segment, and an anti-Müllerian hormone level >1.5 ng/mL before 35 years). MATERIAL AND METHODS:Cohort study of 85 women with MRKH syndrome consulting in our tertiary center. RESULTS:62.4% of women with MRKH syndrome had an exhaustive malformative evaluation according to the French guidelines (Protocole National de Diagnostic et de Soin [PNDS]), of which 76.5% had associated malformations (MRKH type II). Pedigree, when available, showed a family history of infertility or a urogenital tract spectrum anomaly in 60% of cases. Concerning the uterine transplantation selection criteria, when evaluated, 22.6% of women had an anti-Müllerian hormone level <1.5 ng/mL and 36% a vaginal length <7 cm. On the 21 women with complete evaluation of both primary and secondary outcomes, 14 of them would be eligible for a uterine transplantation program at the time of consultation according to the main inclusion criteria of uterine transplantation program. CONCLUSIONS:Women with MRKH syndrome are often inadequately explored for associated malformations. Early assessment and monitoring of the ovarian reserve is key for fertility preservation, especially in the era of uterine transplantation.
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The Mayer-Rokitansky-Küster-Hauser (MRKH) syndrome is the most severe form of congenital malformation of the inner female reproductive tract. It is diagnosed as such when the uterus, the upper vagina and optionally the Fallopian tubes are absent. It accounts for approximately 1 in 5000 live-born females and has been classified in two subtypes: type 1 in the presence of isolated uterovaginal aplasia and type 2 when associated in various combinations with extragenital malformations of the kidneys, skeleton, heart and auditory system. Most cases of MRKH syndrome are sporadic, although a significant number of many familial cases have been reported to date. Despite numerous studies, the genetics of the syndrome remains largely unknown and appears to be heterogeneous: chromosomal abnormalities and some candidate gene variants appear to be associated with a few cases; others have been suggested but not yet confirmed. To date, mainly the GREB1L gene appears to be a serious candidate. Among the remaining hypotheses, the controversial contribution of partial duplications of the SHOX gene is still puzzling, as the deficiency of this gene is a major cause of skeletal adysplasia syndromes. We have attempted to resolve this controversy in a study of 60 MRKH cases. Our results tend to show that SHOX duplications can be the origin of a genetic mechanism responsible for MRKH syndrome.
Congenital uterine anomalies (CUA) may have major impacts on the health and social well-being of affected individuals. Their expressivity is variable, with the most severe end of the spectrum being the absence of any fully or unilaterally developed uterus (aplastic uterus), which is a major feature in Mayer-Rokitansky-Kuster-Hauser syndrome (MRKH). So far, etiologies of CUA remain largely unknown. As reports of familial occurrences argue for strong genetic contributors in some cases, we performed whole exome sequencing in nine multiplex families with recurrence of uterine and kidney malformations, a condition called hereditary urogenital adysplasia. Heterozygous likely causative variants in the gene GREB1L were identified in four of these families, confirming GREB1L as an important gene for proper uterine and kidney development. The apparent mode of inheritance was autosomal dominant with incomplete penetrance. The four families included fetuses with uterovaginal aplasia and bilateral renal agenesis, highlighting the importance to investigate GREB1L in such phenotypes. Subsequent sequencing of the gene in a cohort of 68 individuals with MRKH syndrome or uterine malformation (mostly sporadic cases) identified six additional variants of unknown significance. We therefore conclude that heterozygous GREB1L variants contribute to MRKH syndrome and this probably requires additional genetic or environmental factors for full penetrance.
Mutational Analysis of the LHX1 Gene in a French National Cohort of Patients with Mayer-Rokitansky-Küster-Hauser Syndrome Mayer-Rokitansky-Küster-Hauser syndrome (MRKH syndrome) is characterized by congenital aplasia of the uterus and the upper part of the vagina in women showing normal secondary sexual characteristics development and a normal 46, XX karyotype. MRKH syndrome is a cause of primary amenorrhea with an incidence of approximately 1 in 5,000 newborn girls. Most cases of MRKH syndrome are sporadic, but some familial cases have been reported, suggesting a genetic cause. The genetic basis of MRKH syndrome remains largely unknown and seems heterogeneous. The LHX1 gene has been suggested to be a strong candidate, because (i) inactivation of the ortholog gene (Lim1) in the mouse model causes a Müllerian aplasia, and (ii) it is located in the chromosomal region 17q12, where deletions including this gene have been identified in approximately 5% of MRKH patients. Recently, three relevant heterozygous mutations of the LHX1 gene have been reported in association with the syndrome.
The ITI (inter-trypsine inhibitor) gene family includes five genes (ITIH1 to ITIH5) that encode proteins involved in the dynamics of the extracellular matrix (ECM). ITIH5 was found inactivated by partial deletion in a case of congenital uterovaginal aplasia, a human rare disease also called Mayer-Rokitansky-Küster-Hauser (MRKH) syndrome. The aim of the present study was to analyze the expression of ITIH5 in the uterus in adult life and during embryogenesis in order to establish the involvement of this gene in both normal and pathological conditions of uterus development. This was achieved in mice by reverse transcription-quantitative PCR, whole-mount hybridization, and Western blot analysis. Itih5 expression was much stronger in female genital tract primordia (Müllerian ducts) and derivatives than elsewhere in the body. This gene was strongly expressed during pregnancy and development of the female genital tract, indicating that the encoded protein probably had an important function in the uterus during these periods. Two different specific isoforms of the protein were detected in Müllerian derivatives during embryogenesis and in adults. Although ITIH genes are expected to be predominantly expressed in the liver, ITIH5 is mainly expressed in the uterus during development and adult life. This tends to indicate an additional and specific role of this gene in the female reproductive tract, and furthermore reinforces ITIH5 as a putative candidate gene for MRKH syndrome.
Putative candidate locus: 274000 (TAR).3, 5 Maximal duplication in 1q21.1: 200 kb.3 Partial duplication of the Xpter pseudoautosomal region 1.6 Comment: WNT4 syndrome is close but different from MRKH. It differs from this latter by an hyperandrogenism and gonadal affection.12 It thus needs to be considered in regards to differential diagnosis.13 Nearly 100% using analytical methods described above. Nearly 100% using analytical methods described above. The clinical sensitivity can be dependent on variable factors such as age or family history. In such cases a general statement should be given, even if a quantification can only be made case by case. The synthesis of the literature2, 3, 4, 5, 9, 10 on the genome-wide analysis on MRKH patients was used to estimate that only ~1% show a 1q21.1 rearrangement, ~1% in 16p11.2, ~6% in 17q12 and ~4% in 22q11.21, from a total of 153 cases. The clinical specificity can be dependent on variable factors such as age or family history. In such cases, a general statement should be given, even if a quantification can only be made case by case. 100% of control subjects tested by MLPA (DiGeorge kit) showed negative results. Not applicable. Assume an increased risk based on family history for a non-affected person. Allelic and locus heterogeneity may need to be considered. Index case in that family had been tested: Not applicable. Index case in that family had not been tested: Not applicable. If the test result is negative (please describe): Please assume that the result of a genetic test has no immediate medical consequences. Is there any evidence that a genetic test is nevertheless useful for the patient or his/her relatives? (Please describe). The authors declare no conflict of interest. This work was supported by the EuroGentest, an EU-FP6 supported NoE, contract number 512148 (EuroGentest Unit 3: ‘Clinical genetics, community genetics and public health’, Workpackage 3.2).
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BACKGROUND:Mayer-Rokitansky-Küster-Hauser (MRKH) syndrome is characterized by congenital aplasia of the uterus and the upper part of the vagina in women showing normal development of secondary sexual characteristics and a normal 46, XX karyotype. The uterovaginal aplasia is either isolated (type I) or more frequently associated with other malformations (type II or Müllerian Renal Cervico-thoracic Somite (MURCS) association), some of which belong to the malformation spectrum of DiGeorge phenotype (DGS). Its etiology remains poorly understood. Thus the phenotypic manifestations of MRKH and DGS overlap suggesting a possible genetic link. This would potentially have clinical consequences.METHODS:We searched DiGeorge critical chromosomal regions for chromosomal anomalies in a cohort of 57 subjects with uterovaginal aplasia (55 women and 2 aborted fetuses). For this candidate locus approach, we used a multiplex ligation-dependent probe amplification (MLPA) assay based on a kit designed for investigation of the chromosomal regions known to be involved in DGS.The deletions detected were validated by Duplex PCR/liquid chromatography (DP/LC) and/or array-CGH analysis.RESULTS:We found deletions in four probands within the four chromosomal loci 4q34-qter, 8p23.1, 10p14 and 22q11.2 implicated in almost all cases of DGS syndrome.CONCLUSION:Uterovaginal aplasia appears to be an additional feature of the broad spectrum of the DGS phenotype. The DiGeorge critical chromosomal regions may be candidate loci for a subset of MRKH syndrome (MURCS association) individuals. However, the genes mapping at the sites of these deletions involved in uterovaginal anomalies remain to be determined. These findings have consequences for clinical investigations, the care of patients and their relatives, and genetic counseling.
The nuclear zinc finger protein ZFPIP/Zfp462 is an important factor involved in cell division during the early embryonic development of vertebrates. In pluripotent P19 cells, ZFPIP/Zfp462 takes part in cell proliferation, likely via its role in maintaining chromatin structure. To further define the function of ZFPIP/Zfp462 in the mechanisms of pluripotency and cell differentiation, we constructed a stable P19 cell line in which ZFPIP/Zfp462 knockdown is inducible. We report that ZFPIP/Zfp462 was vital for mitosis and self-renewal in pluripotent P19 cells. Its depletion induced substantial decreases in the expression of the pluripotency genes Nanog, Oct4 and Sox2 and was associated with the transient expression of specific neuronal differentiation markers. We also demonstrated that ZFPIP/Zfp462 expression appears to be unnecessary after neuronal differentiation is induced in P19 cells. Taken together, our results strongly suggest that ZFPIP/Zfp462 is a key chromatin factor involved in maintaining P19 pluripotency and in the early mechanisms of neural differentiation but that it is dispensable in differentiated P19 cells.
Role des cellules epitheliales dans la defense de l'hote. Modele d'epithelium respiratoire infecte par [i]Aspergillus Fumigatus[/i]. 8. Congres National de la Societe Francaise de Microbiologia : Carrefour des Microbiologies du Nord et du Sud
Toti- or pluripotent cells proliferation and/or differentiation have been shown to be strongly related to nuclear chromatin organization and structure over the last past years.We have recently identified ZFPIP/Zfp462 as a zinc finger nuclear factor necessary for correct cell division during early embryonic developmental steps of vertebrates. We thus questioned whether this factor was playing a general role during cell division or if it was somehow involved in embryonic cell fate or differentiation.To achieve this goal, we performed a knock-down experiment in the pluripotent P19 and differentiated 3T3 cell lines, both expressing endogenous ZFPIP/Zfp462. Using specific shRNA directed against ZFPIP/Zfp462 transcripts, we demonstrated that depletion of this protein induced cell death in P19 but had no effect in 3T3 cells. In addition, in the absence of the protein, the P19 cells exhibited a complete destructuration of pericentromeric domains associated with a redistribution of the HPlet proteins and an increase in DNA satellites transcribed RNAs level. These data suggested an instrumental role of ZFPIP/Zfp462 in maintaining the chromatin structure of pluripotent cells. (C) 2010 Elsevier Inc. All rights reserved.
Background: Aspergillus fumigatus, a saprophytic mould, is responsible for life-threatening, invasive pulmonary diseases in immunocompromised hosts. The role of the airway epithelium involves a complex interaction with the inhaled pathogen. Antimicrobial peptides with direct antifungal and chemotactic activities may boost antifungal immune response.Results: The inducible expression of defensins by human bronchial epithelial 16HBE cells and A549 pneumocyte cells exposed to A. fumigatus was investigated. Using RT-PCR and real time PCR, we showed an activation of hBD2 and hBD9 defensin genes: the expression was higher in cells exposed to swollen conidia (SC), compared to resting conidia (RC) or hyphal fragments (HF). The kinetics of defensin expression was different for each one, evoking a putative distinct function for each investigated defensin. The decrease of defensin expression in the presence of heat-inactivated serum indicated a possible link between defensins and the proteins of the host complement system. The presence of defensin peptide hBD2 was revealed using immunofluorescence that showed a punctual cytoplasmic and perinuclear staining. Quantification of the cells stained with anti hBD2 antibody demonstrated that SC induced a greater number of cells that synthesized hBD2, compared to RC or HF. Labelling of the cells with anti-hBD-2 antibody showed a positive immunofluorescence signal around RC or SC in contrast to HF. This suggests co-localisation of hBD2 and digested conidia. The HBD2 level was highest in the supernatants of cells exposed to SC, as was determined by sandwich ELISA. Experiments using neutralising anti-interleukine-1 beta antibody reflect the autocrine mechanism of defensin expression induced by SC. Investigation of defensin expression at transcriptional and post-transcriptional levels demonstrated the requirement of transcription as well as new protein synthesis during A. fumigatus defensin induction. Finally, induced defensin expression in primary culture of human respiratory cells exposed to A. fumigatus points to the biological significance of described phenomena.Conclusion: Our findings provide evidence that respiratory epithelium might play an important role in the immune response during Aspergillus infection. Understanding the mechanisms of regulation of defensin expression may thus lead to new approaches that could enhance expression of antimicrobial peptides for potential therapeutic use during aspergillosis treatment.