Rima Slim
email: rima.slim@muhc.mcgill.ca

Rosemary Fisher
email: r.fisher@imperial.ac.uk

Florian Milhavet

Reda Hemida

Samantha Rojas

Cécile Rittore

| Rashmi Bagga

Monica Aguinaga

Isabelle Touitou
email: isabelle.touitou@inserm.fr

Biallelic NLRP7 variants in patients with recurrent hydatidiform mole: A review and expert consensus

Keywords: biparental moles, expert consensus, Infevers, NLRP7, recurrent hydatidiform mole, subcortical maternal complex

Hydatidiform mole (HM) is an abnormal human pregnancy characterized by excessive growth of placental trophoblasts and abnormal early embryonic development. Following a first such abnormal pregnancy, the risk for women of successive molar pregnancies significantly increases. To date variants in seven maternal-effect genes have been shown to cause recurrent HMs (RHM). NLRP7 is the major causative gene for RHM and codes for NOD-like receptor (NLR) family pyrin domain containing 7, which belongs to a family of proteins involved in inflammatory disorders. Since its identification, all NLRP7 variants have been recorded in Infevers, an online registry dedicated to autoinflammatory diseases (https://infevers.umaimontpellier.fr/web/). Here, we reviewed published and unpublished recessive NLRP7 variants associated with RHM, scored their pathogenicity according to the American College of Medical Genetics classification, and recapitulated all functional studies at the level of both the patients and the conceptions. We also provided data on further variant analyses of 32 patients and genotypes of 36 additional molar pregnancies. This comprehensive review integrates published and unpublished data on NLRP7 and aims at guiding geneticists and clinicians in variant interpretation, genetic counseling, and management of patients with this rare condition.

| BACKGROUND

Hydatidiform mole (HM), or molar pregnancy, is an abnormal human pregnancy characterized by trophoblastic proliferation and limited fetal development. HMs usually result from chromosome abnormalities that lead to an excessive contribution of the paternally derived genome.

Complete HMs (CHMs) are diploid and androgenetic [START_REF] Kajii | Androgenetic origin of hydatidiform mole[END_REF][START_REF] Wake | Androgenesis as a cause of hydatidiform mole[END_REF]. The majority develop following loss of the maternal genome from the ovum and doubling of the paternal genome [START_REF] Jacobs | Complete and partial hydatidiform mole in Hawaii: Cytogenetics, morphology and epidemiology[END_REF][START_REF] Lawler | Genetic studies on hydatidiform moles. I. The origin of partial moles[END_REF], with approximately 15% developing following fertilization of an ovum by two sperms and loss of the maternal chromosomes [START_REF] Xing | Refined diagnosis of hydatidiform moles with p57 immunohistochemistry and molecular genotyping: Updated analysis of a prospective series of 2217 cases[END_REF]. Partial HMs (PHMs) almost always arise following fertilization of an ovum by two sperms, with retention of the maternal chromosomes, and are consequently triploid.

These unusual conceptions are clinically important because of the significant risk, 13.6% after a CHM and 1.1% after a PHM, of the molar tissue progressing to a malignant gestational trophoblastic neoplasia (GTN) which would require chemotherapy [START_REF] Savage | The relationship of maternal age to molar pregnancy incidence, risks for chemotherapy and subsequent pregnancy outcome[END_REF].

Following a pregnancy with an HM, women experience an increased risk of another molar pregnancy, a risk which increases with successive molar pregnancies [START_REF] Eagles | Risk of recurrent molar pregnancies following complete and partial hydatidiform moles[END_REF][START_REF] Savage | The relationship of maternal age to molar pregnancy incidence, risks for chemotherapy and subsequent pregnancy outcome[END_REF]. RHM are estimated to affect 1%-4% of women with a prior HM, most of whom have no family history of HMs while the remaining are familial [START_REF] Berkowitz | Gestational trophoblastic disease. Subsequent pregnancy outcome, including repeat molar pregnancy The[END_REF][START_REF] Horn | Prognostic value of trophoblastic proliferation in complete hydatidiform moles in predicting persistent disease[END_REF][START_REF] Kim | Subsequent reproductive experience after treatment for gestational trophoblastic disease[END_REF][START_REF] Lurain | Pregnancy outcome subsequent to consecutive hydatidiform moles[END_REF][START_REF] Sand | Repeat gestational trophoblastic disease[END_REF][START_REF] Sebire | Risk of recurrent hydatidiform mole and subsequent pregnancy outcome following complete or partial hydatidiform molar pregnancy[END_REF][START_REF] Yapar | Pregnancy outcome after hydatidiform mole, initial and recurrent[END_REF]. Studies of the latter cases led to the mapping of a locus in 19q13.4, in which biallelic variants in the mother are responsible for familial RHM [START_REF] Moglabey | Genetic mapping of a maternal locus responsible for familial hydatidiform moles[END_REF]. While successive molar pregnancies may be triploid dispermic or diploid androgenetic, most molar pregnancies from familial cases have a diploid, biparental genome [START_REF] Helwani | A familial case of recurrent hydatidiform molar pregnancies with biparental genomic contribution[END_REF].

To date, variants in seven maternal-effect genes, NLRP7 [START_REF] Murdoch | Mutations in NALP7 cause recurrent hydatidiform moles and reproductive wastage in humans[END_REF], KHDC3L [START_REF] Parry | Mutations causing familial biparental hydatidiform mole implicate C6orf221 as a possible regulator of genomic imprinting in the human oocyte[END_REF], PADI6 [START_REF] Qian | Biallelic PADI6 variants linking infertility, miscarriages, and hydatidiform moles[END_REF], NLRP5 [START_REF] Rezaei | Novel pathogenic variants in NLRP7, NLRP5, and PADI6 in patients with recurrent hydatidiform moles and reproductive failure[END_REF], MEI1 [START_REF] Dong | Novel biallelic mutations in MEI1: Expanding the phenotypic spectrum to human embryonic arrest and recurrent implantation failure[END_REF], TOP6BL, and REC114 (Nguyen et al., 2018;[START_REF] Wang | Homozygous mutations in REC114 cause female infertility characterised by multiple pronuclei formation and early embryonic arrest[END_REF] have been shown to underlie the genetic etiology of RHM. Of these genes, NLRP7 (previously named NALP7) is the major gene, in which variants explain the etiology of 55% of patients with at least two HMs (Nguyen et al., 2018). NLRP7 is a member of the NOD-like receptor (NLR) protein family that consists of 14 members in humans (NLRP1, NLRP2, NLRP3, NLRP5, etc.) [START_REF] Zambetti | The rhapsody of NLRPs: Master players of inflammation…and a lot more[END_REF]. Loss of one of these proteins, NLRP5, had been shown to be responsible for female infertility in mice due to early embryonic arrest at the two-cell stage [START_REF] Tong | Mater, a maternal effect gene required for early embryonic development in mice[END_REF]. NLRP3, had been shown to play a causal role in cryopyrin-associated autoinflammatory diseases [START_REF] Hoffman | Mutation of a new gene encoding a putative pyrin-like protein causes familial cold autoinflammatory syndrome and Muckle-Wells syndrome[END_REF]. The second gene in which variants are responsible for familial RHM is KHDC3L [START_REF] Parry | Mutations causing familial biparental hydatidiform mole implicate C6orf221 as a possible regulator of genomic imprinting in the human oocyte[END_REF], but explains only 5% of RHM cases. Since the identification of NLRP7, all variants reported in this gene in patients with RHM and other rare or common nucleotide substitutions in the general population, have been recorded in Infevers, an online registry of autoinflammatory variants (https://infevers.umai-montpellier. fr/web/) [START_REF] Milhavet | The infevers autoinflammatory mutation online registry: Update with new genes and functions[END_REF].

The current study was undertaken to review the spectrum of NLRP7 variants associated with RHM, classify them according to the American College of Medical Genetics recommendations (den Dunnen et al., 2016), recapitulate all functional studies at the level of both the patients and their conceptions, and examine the correlation between the nature of the variants in the patients and the phenotype of their conceptions. Our objective is to integrate published and unpublished data on NLRP7 in a comprehensive review to better guide variant interpretation, genetic counseling, and management of patients with this rare condition.

| MATERIALS AND METHODS

| Variant collection and classification

The different steps of data collection used in this review are summarized in Figure 1. A systematic review of NLRP7 variants (NM_001127255.1) recorded in Infevers was undertaken and completed (1) through a PubMed search with the term "NLRP7" to identify missing or recently reported variants, and (2) inclusion of genetic data from 32 additional patients analyzed in the authors' (R. S., I.

T., R. F.) laboratories, but not yet published. All NLRP7 variants located in exons or intronic boundaries, and regulatory regions, were then downloaded from Infevers, inserted in a sheet specifically created for variant classification, and the data were analyzed using an original workflow as previously described [START_REF] Van Gijn | New workflow for classification of genetic variants' pathogenicity applied to hereditary recurrent fevers by the International Study Group for Systemic Autoinflammatory Diseases (INSAID)[END_REF]. In brief, five possible pathogenicity scores, namely benign, likely benign, variant of uncertain significance, likely pathogenic and pathogenic, were blindly and independently assigned to NLRP7 variants by R. S., R. F., S. R., and I.

T. through sequential rounds of voting and/or discussions. The classification was established according to the American College of Medical Genetics and Genomics recommendations and integrated data from both reports and the authors' own unpublished studies using Varsome and the Genetic Variant Interpretation Tool of the University of Maryland School of Medicine. A classification was considered validated if at least 75% of the votes were consistent, provisional if between >50% and 75% of the votes were consistent, and unsolved otherwise. Pathogenicity scores with their respective status were then uploaded to Infevers and made publicly available.

| Patient data collection

The study protocols were approved by the Institutional Review Board

| Genotyping of molar tissues

A total of 36 additional archived formalin-fixed paraffin-embedded (FFPE) molar tissues from patients with biallelic variants in NLRP7 were genotyped. The tissues were sectioned, and the sections were stained with hematoxylin and eosin, and examined using a stereomicroscope. Chorionic villi were separated and their DNA was extracted using QIAamp DNA FFPE Tissue Kit (Qiagen). Maternal DNA was extracted similarly from endometrial tissues present on archived FFPE products of conception or from fresh blood.

Genotyping was performed using of the following multiplex short tandem repeat (STR) markers, the PowerPlex 16 HS System (Promega, Corporation) or the AmpFlSTR Identifiler Plus kit (Applied Biosystems) as previously described [START_REF] Fisher | Clinical utility of selective molecular genotyping for diagnosis of partial hydatidiform mole; a retrospective study from a regional trophoblastic disease unit[END_REF][START_REF] Khawajkie | Microsatellite DNA genotyping and flow cytometry ploidy analyses of formalinfixed paraffin-embedded hydatidiform molar tissues[END_REF].

| RESULTS

| Scoring the pathogenicity of NLRP7 variants

As of 18/06/2021, 275 NLRP7 variants were included in the Infevers database. Where necessary, we have curated the names of the variants at the protein and/or cDNA level to comply with recent F I G U R E 1 Workflow used to collect NLRP7 and patient data for this review. Left panel: classification of NLRP7 variants according to their pathogenicity score. After completing the list of variants included in the Infevers registry (275 different variants at the end of the process) (https://infevers.umaimontpellier.fr/web/search.php?n=8), 155 relevant variants were extracted and a workflow, previously established for autoinflammatory diseases, was used to assign them a score ranging from benign to pathogenic. Right panel: collection of patient data. In parallel, we reviewed the literature and our own records to extract clinical and genetic information from patients meeting the criteria defined in patients and methods. The information collected was included anonymously and homogeneously in a specific database to facilitate statistics and graph generation. The 255 patients thus identified had at least one of the 86 different NLRP7 class 4 or 5 variants identified in this review.

recommendations of the Human Genome Variant Society (HGVS) (den Dunnen et al., 2016;[START_REF] Richards | Standards and guidelines for the interpretation of sequence variants: A joint consensus recommendation of the American College of Medical Genetics and Genomics and the Association for Molecular Pathology[END_REF]. A total of 151 variants, located in exons or intronic boundaries and expected to affect the gene function, were blindly evaluated (Figure 1). After two rounds of voting and a consensus meeting, all but four variants achieved a validated score (https://infevers.umai-montpellier.fr/ web/search.php?n=8).

| Patient and variant characteristics

A total of 255 patients (200 probands) corresponding to our inclusion criteria were identified (Supporting Information: Table S1), of which 32 (13%) have not been previously published. The largest series came from a recent publication describing a cohort of patients of Mexican origin [START_REF] Aguinaga | The genetics of recurrent hydatidiform moles in Mexico: Further evidence of a strong founder effect for one mutation in NLRP7 and its widespread[END_REF]. One hundred and eighty-four of the 246 patients tested (75%) were homozygous for the identified variant (s), although consanguinity was reported or known for only 30% of the cases. The 200 probands (400 alleles) exhibited 86 different variants, with p.Leu750Val being by far the most represented (96/ 400, 24%), followed by p.Arg693Pro (35/400, 8.8%) and p.Leu825* (19/400, 5%) (Figure 2 and Supporting Information: Table S2). Sixtyone of the 86 different variants found in these patients were classified as pathogenic (71%), 14 (16%) as likely pathogenic, and the others (13%) as variants of unknown significance.

NLRP7 variants that are pathogenic or likely pathogenic have been described in all its coding exons with the exception of exon 11 (Figure 2). Of the 86 variants observed, 63 (73.2%) are proteintruncating and 23 (26.7%) are missense (Figure 2). This distribution is significantly different from the frequencies of protein-truncating and missense variants in all other human genes, 43.4% and 44.3%, respectively (p= 0.000011) [START_REF] Stenson | The human gene mutation database: Towards a comprehensive repository of inherited mutation data for medical research, genetic diagnosis and nextgeneration sequencing studies[END_REF]. In addition, while F I G U R E 2 NLRP7 genomic and protein structures with variants observed in biallelic state and data used to score the pathogenicity of the variants. From bottom to top, (a) NLRP7 genomic structure according to RefSeq NC_000019.9 and protein structure according to Q8WX94; (b) number of alleles for each variant; (c) number of genotyped HMs or miscarriages and number of other reproductive outcomes (miscarriages with well-formed fetuses, stillbirths or early neonatal deaths, and live births); and (d) number of alleles for each variant for which there are functional data (ex-vivo cytokine secretion by patient cells, in vitro cytokine data on various cell lines and methylation data on the molar conceptions for each variant. Note that in all histograms, the number of alleles for homozygous variants was counted twice and for heterozygous variants once. comp, compound; END, neonatal death; het, heterozygous; HM, hydatidiform mole; hom, homozygous; LB, live birth; MC, miscarriage; SB, stillbirth.

protein-truncating variants are distributed throughout the protein, missense variants that are pathogenic or likely pathogenic are clustered in the leucine-rich repeat (LRR). To date, only one such missense, p.Leu398Arg, found in a homozygous state in four families of Asian origin, has been reported outside the LRR domain (Figure 2 and Supporting Information: Table S2).

| Ethnic distribution of NLRP7 pathogenic variants associated with RHM

A consistent and intriguing observation since the identification of NLRP7 is that the gene displays several founder variants in various populations [START_REF] Aguinaga | The genetics of recurrent hydatidiform moles in Mexico: Further evidence of a strong founder effect for one mutation in NLRP7 and its widespread[END_REF][START_REF] Slim | A strong founder effect for two NLRP7 mutations in the Indian population: An intriguing observation[END_REF]. The distribution of the variants according to the ethnic origin of the patients is shown in Figure 3. Among the founder variants, p.Leu750Val is the most frequent and accounts for 79% of the alleles found in Mexican cases, while the patients in this population reported less than 10% consanguinity, arguing for an ancient founder effect [START_REF] Aguinaga | The genetics of recurrent hydatidiform moles in Mexico: Further evidence of a strong founder effect for one mutation in NLRP7 and its widespread[END_REF]. Another founder variant in the Mexicans is p.Arg937_Leu938ins54, which has been reported in 10 unrelated patients, and this variant along with p.Leu750Val, appears to be restricted to Mexicans and have not been seen yet in other populations [START_REF] Aguinaga | The genetics of recurrent hydatidiform moles in Mexico: Further evidence of a strong founder effect for one mutation in NLRP7 and its widespread[END_REF].

A mutational hotspot affecting two adjacent nucleotides and changing codon 693 to four different amino acids was observed in several populations, that is, p.Arg693Trp in Turks and other Caucasians from various countries; p.Arg693Gly in one Caucasian family; p.Arg693-Pro, which is the main pathogenic variant in Indo-Pakistanis (39%); and p.Arg693Gln reported so far only in Chinese (11%) (Supporting Information: Table S1). Another variant, p.Asn913Ser, was first observed in the Indo-Pakistani patients [START_REF] Akoury | Live births in women with recurrent hydatidiform mole and two NLRP7 mutations[END_REF][START_REF] Murdoch | Mutations in NALP7 cause recurrent hydatidiform moles and reproductive wastage in humans[END_REF][START_REF] Slim | A strong founder effect for two NLRP7 mutations in the Indian population: An intriguing observation[END_REF], mostly in a compound heterozygous state with p.Arg693Pro, and later in two patients of African descent who carried this variant in a homozygous state despite the absence of consanguinity between their parents [START_REF] Akoury | Live births in women with recurrent hydatidiform mole and two NLRP7 mutations[END_REF][START_REF] Brown | Recurrent pregnancy loss in a woman with NLRP7 mutation: Not all molar pregnancies can be easily classified as either "partial" or "complete" hydatidiform moles[END_REF]. However, among the general healthy population, the frequency of this variant is highest in Africans (minor allele frequency of 0.0015). This suggests its African ancestral origin and later introduction to the Indo-Pakistani population via migration. The p.Arg721Trp and p.Leu825* variants were present mainly in Indo-Pakistani [START_REF] Kou | A recurrent intragenic genomic duplication, other novel mutations in NLRP7 and imprinting defects in recurrent biparental hydatidiform moles[END_REF][START_REF] Murdoch | Mutations in NALP7 cause recurrent hydatidiform moles and reproductive wastage in humans[END_REF][START_REF] Sanchez-Delgado | Absence of maternal methylation in biparental hydatidiform moles from women with NLRP7 maternal-effect mutations reveals widespread placentaspecific imprinting[END_REF]; C. M. [START_REF] Wang | Identification of 13 novel NLRP7 mutations in 20 families with recurrent hydatidiform mole; missense mutations cluster in the leucine-rich region[END_REF] and Chinese [START_REF] Qian | The genetics of recurrent hydatidiform moles in China: Correlations between NLRP7 mutations, molar genotypes and reproductive outcomes[END_REF][START_REF] Zhang | Abnormal processing of IL-1β in NLRP7-mutated monocytes in hydatidiform mole patients[END_REF] patients and to a lesser extent in other populations. In Egyptians, variant p.Glu710Aspfs slightly dominated the others (32% of the alleles) and again this variant has not been reported in other populations [START_REF] Kou | A recurrent intragenic genomic duplication, other novel mutations in NLRP7 and imprinting defects in recurrent biparental hydatidiform moles[END_REF][START_REF] Mahadevan | No evidence for mutations in NLRP7 and KHDC3L in women with androgenetic hydatidiform moles[END_REF][START_REF] Panichkul | Recurrent biparental hydatidiform mole: Additional evidence for a 1.1-Mb locus in 19q13.4 and candidate gene analysis[END_REF]. A large panel of different private variants were present in Chinese, Middle-Easterners, and Caucasians. p57, the protein coded by the cyclin-dependent kinase inhibitor gene, CDKN1C [START_REF] Castrillon | Discrimination of complete hydatidiform mole from its mimics by immunohistochemistry of the paternally imprinted gene product p57KIP2[END_REF]. This gene is paternally imprinted, maternally expressed, in the nuclei of the villous cytotrophoblast and stromal cells of first-trimester placenta. Since the discovery of the association of its differential expression with CHMs and PHMs [START_REF] Chilosi | Differential expression of p57kip2, a maternally imprinted cdk inhibitor, in normal human placenta and gestational trophoblastic disease[END_REF], p57 IHC has been widely used to classify HMs into CHMs and PHMs and sometime to distinguish early CHMs from nonmolar miscarriages. Since androgenetic CHMs lack a copy of the maternal genome, they lack p57 expression while triploid dispermic PHMs, which have one copy of the maternal genome, express p57. At the genotype level, various methods have been introduced, with multiplex STR markers being the most accurate, to determine the parental contribution to the conceptions mainly because it uses several markers from different chromosomes and is suitable for use with degraded DNA extracted from FFPE tissues that are systematically prepared for histopathological diagnosis of all molar conceptions. To date, STR markers and, in most cases, p57 IHC have been used to examine a total of 150 products of conception from patients with recessive NLRP7 variants (Figure 2).

| HMs from patients with biallelic NLRP7 pathogenic or likely pathogenic variants are mostly diploid biparental

By morphology, conceptions from patients with biallelic pathogenic or likely pathogenic NLRP7 variants have been diagnosed as either a CHM, PHM, atypical HM, or miscarriage. A total of 150 products of conception have been genotyped from 75 different patients. Of these products of conception, the genotypes of 114 tissues have been reported and those of 36 additional ones were added to this study. These 150 products of conception have all been found to be diploid biparental with the exception of three HMs that were found to be triploid. In one of these three cases, the HM tissue was found triploid by karyotype and diandric by STR. However, this tissue was genotyped at only two loci, and consequently, its genotype is not convincing [START_REF] Ulker | Novel NLRP7 mutations in familial recurrent hydatidiform mole: Are NLRP7 mutations a risk for recurrent reproductive wastage?[END_REF]. The remaining two HM tissues were analyzed at several STR, were welldocumented to be triploid digynic [START_REF] Allias | A novel NLRP7 protein-truncating mutation associated with discordant and divergent p57 immunostaining in diploid biparental and triploid digynic moles[END_REF][START_REF] Fallahian | Mutations in NLRP7 and KHDC3L confer a complete hydatidiform mole phenotype on digynic triploid conceptions[END_REF], and are indicated by asterisks above their associated variants in Figure 2.

In one of these two HM tissues, the triploid digynic genotype was found to have resulted from the failure of the extrusion of the second polar body during meiosis II [START_REF] Allias | A novel NLRP7 protein-truncating mutation associated with discordant and divergent p57 immunostaining in diploid biparental and triploid digynic moles[END_REF]. Data on these two triploid digynic HMs demonstrated, therefore, another meiotic abnormality, that can occur, although rarely, in the oocytes of patients with biallelic NLRP7 variants. These abnormalities also demonstrate that NLRP7 defects in the oocytes are the main contributor to the molar phenotype, independent of the zygotic genome [START_REF] Allias | A novel NLRP7 protein-truncating mutation associated with discordant and divergent p57 immunostaining in diploid biparental and triploid digynic moles[END_REF].

| Diploid biparental CHMs have milder morphological features than androgenetic CHMs

To better understand the morphological variability of HMs from patients with biallelic NLRP7 variants, two comprehensive studies have examined this question using different approaches.

One study compared 51 diploid biparental CHMs from patients with NLRP7 variants to 27 CHMs from patients with androgenetic RHM, by assessing 11 morphological features [START_REF] Sebire | Histopathological features of biparental complete hydatidiform moles in women with NLRP7 mutations[END_REF]. Of these 11 features, 6 were significantly different between the 2 groups and all the 6 were milder in diploid biparental RHM from patients with recessive NLRP7 variants. Of these features, the most significant were budding villous architecture and the extent of trophoblastic proliferation, with the latter being a feature used by most pathologists to identify HMs and categorize them into CHMs or PHMs. The conclusion of this study was that diploid biparental molar tissues caused by NLRP7 variants have the same, but milder, morphological features than androgenetic CHMs.

| Correlation between the variants in the patients and the phenotypes of the conceptions

The second study investigated genotype phenotype correlation between the nature of the variants, protein truncating versus missense, in patients with biallelic NLRP7 variants and the morphological features of 32 of their conceptions that are diploid biparental [START_REF] Nguyen | Comprehensive genotypephenotype correlations between NLRP7 mutations and the balance between embryonic tissue differentiation and trophoblastic proliferation[END_REF]. Because RHM is a loss-of-function disease, protein-truncating variants, in general, are expected to have a more severe impact on the protein's function than missense variants. This study showed that protein-truncating variants are associated with features of a CHM, namely excessive trophoblastic proliferation, lack of embryonic tissues of inner cell mass origin (fetal nucleated red blood cells, well-formed vessels, fetal membranes, or others), and negative p57 expression in the cytotrophoblast. However, missense variants were associated with some features of a PHM, specifically, mild trophoblastic proliferation, presence of embryonic tissues derived from the inner cell mass (such as fetal nucleated red blood cells within the chorionic villi, well-formed vessels, fetal membranes, and other tissues), and positive p57 expression in the cytotrophoblast, albeit to variable extent.

Applying the same reasoning to the reproductive outcomes of the patients revealed that variants with milder functional consequences, such as missense variants (p.Arg693Pro, p.Pro716Ala, p.Arg721Trp, and p.Asn913Ser), and some hypomorphic splice variants (p.Gly118Aspfs) or protein-truncating variants located toward the C-terminal end of the protein (p.Ile858Hisfs and p.Tyr872*), are permissive for some embryonic tissue differentiation and fetal development to, or beyond, the second trimester, and are associated with late miscarriage with a well-formed fetus, stillbirth, early neonatal death, and live birth [START_REF] Akoury | Live births in women with recurrent hydatidiform mole and two NLRP7 mutations[END_REF][START_REF] Nguyen | Comprehensive genotypephenotype correlations between NLRP7 mutations and the balance between embryonic tissue differentiation and trophoblastic proliferation[END_REF]. A recapitulation of the reproductive outcomes of all published or unpublished (from our groups) cases is provided in

| Impaired de novo DNA methylation during oogenesis

Because diploid biparental RHM from familial cases are similar in morphology to androgenetic CHMs, an important hypothesis to explain their etiology emerged even before the identification of NLRP7 or KHDC3L. This hypothesis suggested that causative genes of diploid biparental HMs must play a role in establishing maternal imprinting marks during oogenesis [START_REF] Sunde | Genetic analysis of repeated, biparental, diploid, hydatidiform moles[END_REF] and has led to several studies to evaluate DNA methylation at differentially methylated regions (DMR) of imprinted genes and at CpG-rich regions of various nonimprinted loci in a total of 10 diploid biparental HMs from patients with the following NLRP7 variants, c.-39-1769_2129+228del [START_REF] Sanchez-Delgado | Absence of maternal methylation in biparental hydatidiform moles from women with NLRP7 maternal-effect mutations reveals widespread placentaspecific imprinting[END_REF], p.Gly118 Aspfs [START_REF] El-Maarri | Maternal alleles acquiring paternal methylation patterns in biparental complete hydatidiform moles[END_REF], p.Trp195* [START_REF] Ito | Novel nonsense mutation in the NLRP7 gene associated with recurrent hydatidiform mole[END_REF], p.Leu 398Arg [START_REF] Hayward | Genetic and epigenetic analysis of recurrent hydatidiform mole[END_REF]), p.Arg693Pro (Sanchez-Delgado et al., 2015), and p.Leu750Val [START_REF] Kou | A recurrent intragenic genomic duplication, other novel mutations in NLRP7 and imprinting defects in recurrent biparental hydatidiform moles[END_REF], all in homozygous state; p.Ser673* with p.Arg721Trp [START_REF] Sanchez-Delgado | Absence of maternal methylation in biparental hydatidiform moles from women with NLRP7 maternal-effect mutations reveals widespread placentaspecific imprinting[END_REF]; and p.Leu750Val with p.Arg937_Leu938ins54 [START_REF] Kou | A recurrent intragenic genomic duplication, other novel mutations in NLRP7 and imprinting defects in recurrent biparental hydatidiform moles[END_REF]. The results of these analyses were consistent between different studies and approaches with the most comprehensive being that of [START_REF] Sanchez-Delgado | Absence of maternal methylation in biparental hydatidiform moles from women with NLRP7 maternal-effect mutations reveals widespread placentaspecific imprinting[END_REF]. This study confirmed previous data on a smaller number of loci and showed a lack or diminished maternal methylation at most imprinted, maternally methylated DMR that was associated with the biallelic transcription of all analyzed imprinted genes. Diploid biparental molar tissues had higher levels of methylation than androgenetic CHM, which completely lacked methylation marks at all maternally methylated DMR, and these data are, therefore, in agreement with the histopathological evaluation of biparental and androgenetic CHMs [START_REF] Sebire | Histopathological features of biparental complete hydatidiform moles in women with NLRP7 mutations[END_REF]. In addition, there was some variability between diploid biparental HMs from sisters with the same variant, or even from the same patient, which is in agreement with the variability of p57 nuclear staining in different HMs from the same patients [START_REF] Nguyen | Comprehensive genotypephenotype correlations between NLRP7 mutations and the balance between embryonic tissue differentiation and trophoblastic proliferation[END_REF].

| Mononuclear cells from patients with biallelic NLRP7 variants have defective cytokine production

The identity of NLRP7 as a member of the NLRP family of proteins with roles in inflammation came as a surprise for scientists working on RHM and those in the imprinting field. The most studied member of this family was NLRP3 which had been shown to cause dominantly inherited auto-inflammatory conditions by upregulating interleukin (IL)-1B and tumor necrosis factor (TNF) secretion without and after ex-vivo stimulation [START_REF] Aksentijevich | De novo CIAS1 mutations, cytokine activation, and evidence for genetic heterogeneity in patients with neonatal-onset multisystem inflammatory disease (NOMID): A new member of the expanding family of pyrin-associated autoinflammatory diseases[END_REF]. Investigating the inflammatory response of ex-vivo stimulated peripheral blood mononuclear cells from two patients with biallelic NLRP7 variants (p.Gly118Aspfs and p.Arg693Trp, both in a homozygous state) demonstrated that these cells, as opposed to those of patients with NLRP3 variants, have decreased IL-1B and TNF secretion in the extracellular milieu. Another recent study by [START_REF] Zhang | Abnormal processing of IL-1β in NLRP7-mutated monocytes in hydatidiform mole patients[END_REF], reproduced these results using the same assay on cells from six other patients with biallelic NLRP7 variants (p.Arg432*, p.Arg693Gln, and p.Arg721Trp in homozygous state and the following in compound heterozygous state, p.Asp722Gly with p.Trp920*, p.Asp722Gly with p.Leu825*, and p.Arg432* with p.Ala719Val). This study confirmed the requirement of normal NLRP7 for normal IL-1B and TNF production. Based on the cellular localization of NLRP7 protein in peripheral blood mononuclear cells to the Golgi apparatus and the microtubule-organizing center, defective IL-1B secretion was attributed to the impaired formation of the cellular cytoskeleton. Beside the role of NLRP7 variants in decreasing cytokine secretion, two other studies have documented functional consequences of five of its variants (p.Glu99*, p.Gly118Aspfs, p.Arg693Trp, p.Arg693Pro, and p.Asp657Val) on inflammasome activation in vitro [START_REF] Khare | An NLRP7containing inflammasome mediates recognition of microbial lipopeptides in human macrophages[END_REF][START_REF] Messaed | NLRP7, a nucleotide oligomerization domain-like receptor protein, is required for normal cytokine secretion and co-localizes with Golgi and the microtubuleorganizing center[END_REF], supporting the pathogenicity of these variants.

| DISCUSSION

RHM resulting from variants in NLRP7 is a rare condition but important for women who are affected and wish to achieve a normal pregnancy. Analysis of variants in NLRP7 has identified a number of protein-truncating variants distributed throughout the gene with a much smaller proportion of missense variants. While most variants are private and have been reported in a small number of patients, founder variants have been described in several populations.

Regardless of morphology, none of the 150 products of conception that were genotyped had the typical androgenetic or triploid diandric genotype normally associated with a CHM or a PHM, respectively, almost all HMs (98.6%) that were genotyped were found diploid biparental. Approximately 20% of the conceptions were described as miscarriages. Most of these may not have been examined by morphology, p57 IHC, or genotype analysis and could potentially represent additional molar pregnancies. Despite the poor reproductive outcomes for women with biallelic NLRP7 variants, 12 patients achieved a term pregnancy with their own oocytes, while three further patients had two term pregnancies, one of which resulted in dizygotic twins. Of the 16 offspring, 2 experienced early neonatal death, and 1 exhibited intrauterine growth restriction.

Where assisted reproductive technology was attempted, this was unsuccessful or resulted in a further HM until the introduction of ovum donation, which has enabled at least 11 successful live births [START_REF] Aguinaga | The genetics of recurrent hydatidiform moles in Mexico: Further evidence of a strong founder effect for one mutation in NLRP7 and its widespread[END_REF][START_REF] Akoury | Live births in women with recurrent hydatidiform mole and two NLRP7 mutations[END_REF][START_REF] Cozette | Pregnancy after oocyte donation in a patient with NLRP7 gene mutations and recurrent molar hydatidiform pregnancies[END_REF][START_REF] Fisher | What a difference an egg makes[END_REF][START_REF] Rezaei | Novel pathogenic variants in NLRP7, NLRP5, and PADI6 in patients with recurrent hydatidiform moles and reproductive failure[END_REF]This study). Pathogenic recessive variants in NLRP7 are the major cause of RHM. The primary role of NLRP7 is in the oocyte where it localizes to the subcortical region [START_REF] Akoury | Live births in women with recurrent hydatidiform mole and two NLRP7 mutations[END_REF] and forms the subcortical maternal complex (SCMC), a multimeric protein that is unique to mammalian oocytes (Figure 4). The SCMC consists of oocyte-specific cytoskeletal structures and is the site of ribosomes and mRNA storage [START_REF] Li | A subcortical maternal complex essential for preimplantation mouse embryogenesis[END_REF]. In mice, variants in seven SCMC proteins, of which NLRP2 (the paralog of NLRP7) [START_REF] Meyer | Germline mutation in NLRP2 (NALP2) in a familial imprinting disorder (Beckwith-Wiedemann syndrome[END_REF], NLRP5 [START_REF] Tong | Mater, a maternal effect gene required for early embryonic development in mice[END_REF], PADI6 [START_REF] Xu | Molecular characteristics, clinical implication, and cancer immunity interactions of pyroptosis-related genes in breast cancer[END_REF], TLE6 [START_REF] Alazami | TLE6 mutation causes the earliest known human embryonic lethality[END_REF], and KHDC3 (the ortholog of KHDC3L) [START_REF] Ohsugi | Maternally derived FILIA-MATER complex localizes asymmetrically in cleavagestage mouse embryos[END_REF] lead to several abnormalities in the oocytes that culminate in an impaired embryonic genome activation (EGA) at the two-to four-cell stage and consequently embryonic arrest by the blastocyst stage [START_REF] Li | A subcortical maternal complex essential for preimplantation mouse embryogenesis[END_REF].

NLRP7 is the major gene for RHM but other members of the SCMC have also been shown to be responsible for RHM [START_REF] Qian | Biallelic PADI6 variants linking infertility, miscarriages, and hydatidiform moles[END_REF][START_REF] Rezaei | Novel pathogenic variants in NLRP7, NLRP5, and PADI6 in patients with recurrent hydatidiform moles and reproductive failure[END_REF]. Of these, KHDC3L, is the second most important gene for RHM [START_REF] Parry | Mutations causing familial biparental hydatidiform mole implicate C6orf221 as a possible regulator of genomic imprinting in the human oocyte[END_REF]. Two other genes, PADI6 and NLRP5, explain extremely rare cases [START_REF] Qian | Biallelic PADI6 variants linking infertility, miscarriages, and hydatidiform moles[END_REF][START_REF] Rezaei | Novel pathogenic variants in NLRP7, NLRP5, and PADI6 in patients with recurrent hydatidiform moles and reproductive failure[END_REF] (Figure 5). Patients with recessive NLRP7 or KHDC3L variants produce normal numbers of oocytes, both spontaneously and after ovulation induction. However, their conceptions display variable degrees of hypomethylation at the DMR of several imprinted, maternally methylated genes that acquire their methylation marks during oogenesis [START_REF] El-Maarri | Maternal alleles acquiring paternal methylation patterns in biparental complete hydatidiform moles[END_REF][START_REF] Hayward | Genetic and epigenetic analysis of recurrent hydatidiform mole[END_REF][START_REF] Ito | Novel nonsense mutation in the NLRP7 gene associated with recurrent hydatidiform mole[END_REF][START_REF] Kou | A recurrent intragenic genomic duplication, other novel mutations in NLRP7 and imprinting defects in recurrent biparental hydatidiform moles[END_REF][START_REF] Sanchez-Delgado | Absence of maternal methylation in biparental hydatidiform moles from women with NLRP7 maternal-effect mutations reveals widespread placentaspecific imprinting[END_REF]. This hypomethylation was originally believed to be restricted to imprinted genes, but a recent elegant study on single oocytes from a patient with biallelic variants in KHDC3L demonstrated that this hypomethylation affects de novo DNA methylation of the entire oocyte genome [START_REF] Demond | A KHDC3L mutation resulting in recurrent hydatidiform mole causes genome-wide DNA methylation loss in oocytes and persistent imprinting defects post-fertilisation[END_REF]. Despite the hypomethylation defect, oocytes from patients with biallelic NLRP7 or KHDC3L variants are capable of normal fertilization since almost all their products of conception are diploid biparental. However, the abnormalities appear to start during preimplantation development, some of which may manifest at the morphological or genetic level.

Despite the ancient recognition of HMs and the increasing use of assisted reproductive technologies in the past 40 years, until 2017, no one has ever reported how a HM develops during the preimplantation F I G U R E 4 Mechanism of RHM associated with biallelic NLRP7 variants. A suggested model that recapitulates the various roles of NLRP7 deficiency in the pathology of RHM. The primary defect is in the oocyte that fails to acquire normal methylation marks all over the maternal genome. This defect does not affect fertilization, which appears normal. However, early preimplantation development is impaired and the molar tissues display a shift from tissue differentiation toward proliferation. Because blood mononuclear cells from the patients fail to secrete normal amounts of IL-1B, the patients fail to mount an appropriate inflammatory response to reject their arrested pregnancies and the delayed rejection of these pregnancies contributes to the molar phenotype. IL1B, interleukin 1 beta; RHM, recurrent hydatidiform mole.

period. The only account of such an event was published recently by Sills on a patient with RHM caused by a homozygous variant in NLRP7 (p.Arg937_Leu938ins54) [START_REF] Sills | Pathogenic variant in NLRP7 (19q13.42) associated with recurrent gestational trophoblastic disease: Data from early embryo development observed during in vitro fertilization[END_REF]. Despite appropriate counseling, the patient insisted on undergoing assisted reproductive technology with her own oocytes. Ovulation was then induced, and the patient produced a normal number of oocytes that were morphologically normal and were subject to intra-cytoplasmic sperm injection. Most injected oocytes progressed to two pronuclei but all the embryos manifested morphological abnormalities and arrested by the blastocyst stage and none of the blastocysts was judged by the embryologist to be suitable for transfer (Figure 4). Most likely, this is what happens in the natural conceptions of such patients, but nature appears to be more tolerant and less stringent than embryologists; such blastocysts reach the uterus, implant, and lead to HMs that are diploid biparental. In these HMs, there is an inverse correlation between the differentiation of embryonic tissues of inner cell mass and the proliferation of the trophoblast that seems to depend on the severity of the variants in the patients and consequently the severity of the oocyte defects. Intriguingly, this inverse correlation between the degree of embryonic tissue differentiation and trophoblastic proliferation applies to all types of moles (and products of conception), regardless of their genotype and is by itself fascinating and remains to be elucidated at the molecular level.

Finally, NLRP7 variants decrease cytokine production [START_REF] Messaed | NLRP7, a nucleotide oligomerization domain-like receptor protein, is required for normal cytokine secretion and co-localizes with Golgi and the microtubuleorganizing center[END_REF], which reduces maternal reaction to abnormal pregnancies and makes the patients more tolerant to keep abnormal pregnancies for a longer time. The delayed rejection of these abnormal pregnancies, in which embryonic development had arrested much earlier, contributes to the molar phenotype (Figure 4). This review recapitulates the different genetic defects that may occur in the NLRP7 gene and provides a comprehensive and updated classification of its variants according to their pathogenicity, associated phenotypes, and available functional data. Definitive confirmation of the diagnosis at the genetic level requires the identification of two pathogenic or likely pathogenic biallelic variants. Also, private variants that are extremely rare in the general population can be considered causative if their biallelic status is demonstrated. Analysis of NLRP7-associated RHM variants primarily relies on bidirectional Sanger sequencing of all coding exons and flanking intronic sequences, which allows the identification of point variants, or small genetic rearrangements (that are less than 20 bp) such as duplications, deletions, and insertions. However, larger rearrangements and complex variants have also been found [START_REF] Kou | A recurrent intragenic genomic duplication, other novel mutations in NLRP7 and imprinting defects in recurrent biparental hydatidiform moles[END_REF][START_REF] Reddy | The genomic architecture of NLRP7 is Alu rich and predisposes to disease-associated large deletions[END_REF], and have been explained by the particular genomic architecture of NLRP7 and the richness of its introns in Alu repetitive elements (accounting for 48% of its intronic sequences) [START_REF] Reddy | The genomic architecture of NLRP7 is Alu rich and predisposes to disease-associated large deletions[END_REF]. Therefore, a complementary approach should be performed in order not to erroneously rule out the diagnosis of NLRP7-associated RHM, especially in patients in whom only one pathogenic allele has been detected using routine variant analysis. Multiplex ligation-dependent Probe Amplification for the study of gene copy number variations, long-range polymerase chain reaction (PCR), or analysis of genomic DNA dosage by quantitative real-time PCR (RT-PCR) (Nguyen et al., 2018;[START_REF] Reddy | The genomic architecture of NLRP7 is Alu rich and predisposes to disease-associated large deletions[END_REF] have proven successful for the detection of large deletion and complex variants. In addition, the functional impact of newly detected variants with a putative impact on gene transcription, for example, located at noncanonical splice sites, can be characterized using RT-PCR on RNA from patient cells to demonstrate the presence of abnormal transcripts or the loss of NLRP7 transcripts.

RHM are genetically heterogeneous, implying that other known causative genes must be evaluated before excluding an inherited genetic etiology. NLRP7 is the major gene for this condition and is the first to be analyzed for variants. When its involvement is not detected, the following genes need to be analyzed, KHDC3L, which explains about 5% of RHM cases (Nguyen et al., 2018), and PADI6 and NLRP5, which explain approximately 1% and 0.5% of RHM cases, respectively (Figure 5). It is important to note that the main manifestations of biallelic variants in the latter two genes are female infertility, early embryonic arrest during the preimplantation period, and children with multilocus imprinting disorders particularly Beckwith-Wiedemann and Silver Russell Syndromes. Three other genes, MEI1, TOP6BL, and REC114, are responsible for androgenetic RHM and were identified in 2018; each explaining approximately 0.5% of patients with RHM who are negative for NLRP7-and KHDC3L-variants (Figure 5). Biallelic variants in these genes also appear to be responsible mainly for infertility and early embryonic arrest during the preimplantation period [START_REF] Dong | Novel biallelic mutations in MEI1: Expanding the phenotypic spectrum to human embryonic arrest and recurrent implantation failure[END_REF][START_REF] Jiao | A TOP6BL mutation abolishes meiotic DNA double-strand break formation and causes human infertility[END_REF][START_REF] Wang | Homozygous mutations in REC114 cause female infertility characterised by multiple pronuclei formation and early embryonic arrest[END_REF], but it is too early to have a clear picture of their involvement in the various forms of reproductive failure. It is expected that such information will be soon available since most genetic laboratories now offer high-throughput F I G U R E 5 Genetic etiologies of RHM. Percentages of patients with RHM and pathogenic/likely pathogenic variants in the known genes. The violet shades are used for genes associated with diploid biparental RHM, red and orange/yellow colors for genes associated with unknown genotypic types of HM; and blue shades for genes associated with androgenetic RHM.

sequencing allowing simultaneous screening of a panel of some genes or all genes using whole exome/genome sequencing. Accurate genetic counseling of patients with RHM will, therefore, depend on the mutated gene and type of variants presented by the patients.

When the molecular defect is located in the NLRP7 gene, Figure 2 shows that, as expected, protein-truncating variants generally have a more severe impact on protein function than missense variants. The direct consequence of these observations is that patients with the latter type of variants are more likely to have a normal pregnancy.

Despite this, attempting a natural pregnancy is not recommended as normal pregnancies in such patients are rare and there is a high risk of another molar pregnancy with the risk of persistent disease which may require chemotherapy. This review will help guide clinicians in managing and counseling patients and their relatives, particularly female siblings contemplating pregnancy, based on phenotypegenotype correlations now known from case accumulation.

of

  McGill University (A01_M07_03A) and the Joint Research Compliance Office of Imperial College London and Imperial College Healthcare NHS Trust (reference number 15HH2513). Patients with RHM were identified from publications accumulated over the years and unpublished work performed in our three laboratories (Figure 1, right panel). Inclusion criteria were patients with two or more HMs in whom sequencing of NLRP7 showed homozygosity or compound heterozygosity for variants in NLRP7, of which at least one is pathogenic or likely pathogenic. While biallelic variants could not always be phased by sequencing samples from other family members, they were assumed to be in trans based on their scarcity in the general population (https://gnomad.broadinstitute.org). A specific anonymized database in Microsoft Access was built to collect the distribution of NLRP7 variants in the patients, the reproductive outcomes of the patients, the number of conceptions genotyped or analyzed for DNA methylation, ex-vivo cytokine secretion by patient's cells, and other in vitro assays in cell lines that support the pathogenicity of the variants. Where available, details of pathology, including p57 immunostaining of products of conception were recorded. Nine sisters of patients, who also experienced RHM, but from whom blood samples were not available for DNA sequencing were assumed to have the same variants as the probands and included to provide further data in relation to reproductive outcomes in women with RHM.

  3.4 | Roles and functions of NLRP73.4.1 | Diagnosis of HMsThe diagnosis of HMs was originally based on microscopic morphological evaluation[START_REF] Szulman | The syndromes of hydatidiform mole. II. Morphologic evolution of the complete and partial mole[END_REF]. Another important technique for molar diagnosis is immunohistochemistry (IHC) for the expression of F I G U R E 3 Ethnic distribution of NLRP7 pathogenic variants. Using data on the probands, the frequency of each variant was calculated in different populations. Only variants with a frequency greater than 5% in a given population are represented in the pie charts. Caucasians: England: N = 10; France: N = 8; Not defined: N = 6; New Zealand: N = 4; United States: N = 4; Armenia, Canada, Estonia, Greece, Ireland, Italy, Germany, Spain, and Sweden: N = 2, each. Middle Easterners: Iran: N = 6; Saudi Arabia, N = 4; Algeria, Cyprus, Lebanon, Qatar, Syria, Tunisia: N = 2, each.

Figure 2

 2 Figure 2 and shows the association of fetal development (HM and fetus) and live birth with missense variants, one hypomorphic splice variant, or protein-truncating variants located in the C-terminal part of the protein.

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ACKNOWLEDGMENTS

The authors wish to thank the patients and their relatives who participated in the various studies recapitulated in this review, the clinicians who referred the cases, P. K. Sekharan for referring a patient whose data are reported only in this study, and Maryam Rezaei for her help in the preparation of the raw data of Supporting Information: Table S1. We also wish to thank all trainees who contributed over the years to the generation of the data reviewed in this manuscript, the Canadian Institutes of Health Research grant number PJT-180509, PJT-155998, and MOP-130364; French ministry of health; the Imperial College Experimental Cancer Medicine Centre, and the National Institute for Health Research Biomedical Research Centre.

Funding information Canadian Institutes of Health Research under the following grants PJT-180509, PJT-155998, and MOP-130364 to RS; The French ministry of health to IT; and the Imperial College Experimental Cancer Medicine Centre and the National Institute for Health Research Biomedical Research Centre to RF

DATA AVAILABILITY STATEMENT

The data that supports the findings of this study are available in the supplementary material of this article. Variant data are available in the Infevers online autoinflammatory diseases registry (https://

CONFLICT OF INTEREST

The authors declare no conflict of interest.

SUPPORTING INFORMATION

Additional supporting information can be found online in the Supporting Information section at the end of this article.

How to cite this article: Slim, R., Fisher, R., Milhavet, F., Hemida, R., Rojas, S., Rittore, C., Bagga, R., Aguinaga, M., & Touitou, I. (2022). Biallelic NLRP7 variants in patients with recurrent hydatidiform mole: A review and expert consensus. Human Mutation, 43, 1732-1744. https://doi.org/10.1002/humu.24439


est destinée au dépôt

The conventional methods, usually performed in vivo, provide limited information regarding sensory and neuromuscular excitability properties. In the present work, we review the new minimally invasive methods that have been improved to supplement the conventional electrophysiological methods. In particular, the automated sequence of multiple excitability tests developed by Professor Bostock (Qtrac©, Institute of Neurology, London, UK) to assess sensory and neuromuscular excitability in clinical neurophysiology, has been adapted to animal models in vivo, initially in rats and, more recently, in mice. This method is particularly appropriate for venom toxin injections and repeated recordings from the same animal cohort, making it a promising tool to appraise the progression of toxin effects, and that of an eventual given treatment, on the sensory and neuromuscular excitability of animal models in vivo. The in vivo efficiency in mice and longterm follow-up of the effects of sub-lethal doses of spider and conus venom toxins will be emphasised. It is indubitable that this method brings specific information regarding changes in ion transfer and membrane properties induced by a given venom toxin which, thereby, will help to a better characterization of toxin action on the sensory and neuromuscular excitability properties, in vivo.

Mots clés

Toxins, in vivo electrophysiology, sensory and neuromuscular excitability

AJOURNEES

  non-invasive method to appraise time-dependent effects of venom toxins on the mouse neuromuscular excitability in vivo Tânia C. Gonçalves, Michel Partiseti, Denis Servent, Evelyne Benoit To cite this version: Tânia C. Gonçalves, Michel Partiseti, Denis Servent, Evelyne Benoit. A non-invasive method to appraise time-dependent effects of venom toxins on the mouse neuromuscular excitability in vivo. Journées scientifiques du programme national de la lutte contre le terrorisme (projet NRBC-E), Jan 2018, Gif-sur-Yvette, France. hal-04465262

invasive method to appraise time-dependent effects of venom toxins on the mouse neuromuscular excitability in vivo

	Titre du Poster A non-Auteurs Tânia C. Gonçalves, Michel Partiseti, Denis Servent et
		Evelyne Benoit
	Coordonnées du laboratoire	CEA, Institut des Sciences du Vivant Frédéric Joliot,
	principal	SIMOPRO, Université Paris-Saclay, 91191 Gif-sur-Yvette,
		France
	Adresse de messagerie de l'auteur	evelyne.benoit@cea.fr
	principal
	Résumé de 200 à 300 mots