Publications by authors named "Chloe Quelin"

38 Publications

Severe Phenotype in Patients with Large Deletions of .

Cancers (Basel) 2021 Jun 13;13(12). Epub 2021 Jun 13.

Lille University, Inserm, CHU Lille, U1172 - LilNCog - Lille Neuroscience & Cognition, F-59000 Lille, France.

Complete deletion of the gene is identified in 5-10% of patients with neurofibromatosis type 1 (NF1). Several studies have previously described particularly severe forms of the disease in NF1 patients with deletion of the locus, but comprehensive descriptions of large cohorts are still missing to fully characterize this contiguous gene syndrome. -deleted patients were enrolled and phenotypically characterized with a standardized questionnaire between 2005 and 2020 from a large French NF1 cohort. Statistical analyses for main NF1-associated symptoms were performed an NF1 reference population. A deletion of the gene was detected in 4% (139/3479) of molecularly confirmed NF1 index cases. The median age of the group at clinical investigations was 21 years old. A comprehensive clinical assessment showed that 93% (116/126) of -deleted patients fulfilled the NIH criteria for NF1. More than half had café-au-lait spots, skinfold freckling, Lisch nodules, neurofibromas, neurological abnormalities, and cognitive impairment or learning disabilities. Comparison with previously described "classic" NF1 cohorts showed a significantly higher proportion of symptomatic spinal neurofibromas, dysmorphism, learning disabilities, malignancies, and skeletal and cardiovascular abnormalities in the -deleted group. We described the largest -deleted cohort to date and clarified the more severe phenotype observed in these patients.
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http://dx.doi.org/10.3390/cancers13122963DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8231977PMC
June 2021

Clinical delineation of SETBP1 haploinsufficiency disorder.

Eur J Hum Genet 2021 Aug 19;29(8):1198-1205. Epub 2021 Apr 19.

Department of Human Genetics, Radboud University Medical Center, Nijmegen, The Netherlands.

SETBP1 haploinsufficiency disorder (MIM#616078) is caused by haploinsufficiency of SETBP1 on chromosome 18q12.3, but there has not yet been any systematic evaluation of the major features of this monogenic syndrome, assessing penetrance and expressivity. We describe the first comprehensive study to delineate the associated clinical phenotype, with findings from 34 individuals, including 24 novel cases, all of whom have a SETBP1 loss-of-function variant or single (coding) gene deletion, confirmed by molecular diagnostics. The most commonly reported clinical features included mild motor developmental delay, speech impairment, intellectual disability, hypotonia, vision impairment, attention/concentration deficits, and hyperactivity. Although there is a mild overlap in certain facial features, the disorder does not lead to a distinctive recognizable facial gestalt. As well as providing insight into the clinical spectrum of SETBP1 haploinsufficiency disorder, this reports puts forward care recommendations for patient management.
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http://dx.doi.org/10.1038/s41431-021-00888-9DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8385049PMC
August 2021

Clinical spectrum of MTOR-related hypomelanosis of Ito with neurodevelopmental abnormalities.

Genet Med 2021 08 8;23(8):1484-1491. Epub 2021 Apr 8.

Pediatric and Fetal Imaging Department, Hospices Civils de Lyon, Bron, France.

Purpose: Hypomelanosis of Ito (HI) is a skin marker of somatic mosaicism. Mosaic MTOR pathogenic variants have been reported in HI with brain overgrowth. We sought to delineate further the pigmentary skin phenotype and clinical spectrum of neurodevelopmental manifestations of MTOR-related HI.

Methods: From two cohorts totaling 71 patients with pigmentary mosaicism, we identified 14 patients with Blaschko-linear and one with flag-like pigmentation abnormalities, psychomotor impairment or seizures, and a postzygotic MTOR variant in skin. Patient records, including brain magnetic resonance image (MRI) were reviewed. Immunostaining (n = 3) for melanocyte markers and ultrastructural studies (n = 2) were performed on skin biopsies.

Results: MTOR variants were present in skin, but absent from blood in half of cases. In a patient (p.[Glu2419Lys] variant), phosphorylation of p70S6K was constitutively increased. In hypopigmented skin of two patients, we found a decrease in stage 4 melanosomes in melanocytes and keratinocytes. Most patients (80%) had macrocephaly or (hemi)megalencephaly on MRI.

Conclusion: MTOR-related HI is a recognizable neurocutaneous phenotype of patterned dyspigmentation, epilepsy, intellectual deficiency, and brain overgrowth, and a distinct subtype of hypomelanosis related to somatic mosaicism. Hypopigmentation may be due to a defect in melanogenesis, through mTORC1 activation, similar to hypochromic patches in tuberous sclerosis complex.
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http://dx.doi.org/10.1038/s41436-021-01161-6DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8354853PMC
August 2021

Phenotypic spectrum and genomics of undiagnosed arthrogryposis multiplex congenita.

J Med Genet 2021 Apr 5. Epub 2021 Apr 5.

Department of Pediatric Neurology, APHP-Bicêtre Hospital, Le Kremlin-Bicêtre, France.

Background: Arthrogryposis multiplex congenita (AMC) is characterised by congenital joint contractures in two or more body areas. AMC exhibits wide phenotypic and genetic heterogeneity. Our goals were to improve the genetic diagnosis rates of AMC, to evaluate the added value of whole exome sequencing (WES) compared with targeted exome sequencing (TES) and to identify new genes in 315 unrelated undiagnosed AMC families.

Methods: Several genomic approaches were used including genetic mapping of disease loci in multiplex or consanguineous families, TES then WES. Sanger sequencing was performed to identify or validate variants.

Results: We achieved disease gene identification in 52.7% of AMC index patients including nine recently identified genes (, , , , , , , and ). Moreover, we identified pathogenic variants in and expanding the phenotypes associated with these genes. The most frequent cause of AMC was a primary involvement of skeletal muscle (40%) followed by brain (22%). The most frequent mode of inheritance is autosomal recessive (66.3% of patients). In sporadic patients born to non-consanguineous parents (n=60), de novo dominant autosomal or X linked variants were observed in 30 of them (50%).

Conclusion: New genes recently identified in AMC represent 21% of causing genes in our cohort. A high proportion of de novo variants were observed indicating that this mechanism plays a prominent part in this developmental disease. Our data showed the added value of WES when compared with TES due to the larger clinical spectrum of some disease genes than initially described and the identification of novel genes.
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http://dx.doi.org/10.1136/jmedgenet-2020-107595DOI Listing
April 2021

Basal Ganglia Dysmorphism in Patients With Aicardi Syndrome.

Neurology 2021 03 4;96(9):e1319-e1333. Epub 2020 Dec 4.

From the Department of Brain and Behavioural Neurosciences (S.M., A.P., M. Formica, S.O.) and Department of Public Health Experimental and Forensic Medicine, Biostatistic and Clinical Epidemiology Unit (P. Borrelli), University of Pavia; Pediatric Neurology Unit (S.M., M. Mastrangelo, P.V.), V. Buzzi Children's Hospital, Milan; Department of Neuroradiology (A.P.), Child Neurology and Psychiatry Unit (R.B., V.D.G., S.O.), and Department of Internal Medicine and Therapeutics, Member of the ERN EpiCARE, University of Pavia and Clinical Trial Center (E.P.), IRCCS Mondino Foundation Pavia; Neuroimaging Lab (F.A.) and Neuropsychiatry and Neurorehabilitation Unit (R.R.), Scientific Institute, IRCCS Eugenio Medea, Bosisio Parini, Lecco; Child Neuropsychiatric Unit (P.A., L.G.), Civilian Hospital, Brescia; Scientific Institute (P. Bonanni, A.D., E.O.), IRCCS E. Medea, Epilepsy and Clinical Neurophysiology Unit, Conegliano, Treviso; UOC Child Neuropsychiatry (B.D.B., F.D.), Department of Surgical Sciences, Dentistry, Gynecology and Pediatrics, University of Verona, Italy; Département de Neurologie Pédiatrique (N.D.), Hôpital Universitaire des Enfants Reine Fabiola, Université Libre de Bruxelles, Belgium; AdPueriVitam (O.D.), Antony; Service d'Explorations Fonctionnelles (S.G.), Centre de Médecine du Sommeil, l'Hôpital Àntoine Béclère, AP-HP, Clamart; Pediatrics Departement (S.G.), André-Grégoire Hospital, Centre Hospitalier Inter Communal, Montreuil, France; Pediatric Neurology, Neurogenetics and Neurobiology Unit and Laboratories, Neuroscience Department (R.G., M. Montomoli, M.C.) and Radiology (M. Mortilla), A. Meyer Children's Hospital, Member of the ERN EpiCARE, University of Florence; IRCCS Stella Maris Foundation (R.G.), Pisa; Child Neuropsychiatry Unit, Epilepsy Center (F.L.B., A.V.), San Paolo Hospital, Department of Health Sciences, Università degli Studi di Milano, Milan; Child Neurology, NESMOS Department (P.P.), Faculty of Medicine & Psychology, Sant'Andrea Hospital, Sapienza University, Rome; Department of Neuroradiology (L.P.), Pediatric Neuroradiology Section, ASST Spedali Civili, Brescia; Pediatric Neuroradiology Unit (M.S.), IRCCS Istituto Giannina Gaslini, Genova; Neurology Unit, Department of Neuroscience, Member of the ERN EpiCARE (F.V.), Oncological Neuroradiology Unit, Department of Imaging, IRCCS (G.C.), and Department of Neuroscience and Neurorehabilitation (A.F.), Bambino Gesù Children's Hospital, Rome, Italy; Institut Imagine (N.B.-B.), Université Paris Descartes-Sorbonne Paris Cités; Pediatric Neurology (N.B.-B., I.D.), Necker Enfants Malades Hospital, Member of the ERN EpiCARE, Assistance Publique-Hôpitaux de Paris; INSERM UMR-1163 (N.B.-B., A. Arzimanoglou), Embryology and Genetics of Congenital Malformations, France; UOC Neurochirurgia (A. Accogli, V.C.), Pediatric Neurology and Muscular Diseases Unit, Department of Neurosciences, Rehabilitation, Ophthalmology, Genetics, Maternal and Child Health, University of Genoa (F.Z.), and Laboratory of Neurogenetics and Neuroscience, IRCCS (F.Z.), Istituto Giannina Gaslini, Genoa, Italy; Neurochirurgie Pédiatrique (M.B.), Hôpital NEM, Paris, France; Centre Médico-Chirurgical des Eaux-Vives (V.C.-V.), Swiss Medical Network, Genève, Switzerland; Neuroradiology Unit (L.C.) and Developmental Neurology Unit (S.D.), Foundation IRCCS C. Besta Neurological Institute, Milan; Service de Génétique (M.D.-F.), AMH2, CHU Reims, UFR de Médecine, Reims, France; Epilepsy Centre-Clinic of Nervous System Diseases (G.d.), Riuniti Hospital, Foggia, Italy; MediClubGeorgia Co Ltd (N.E.), Tbilisi, Georgia; Epilepsy Center (N.E.), Medical Center, Faculty of Medicine, University of Freiburg, Germany; Child and Adolescence Neurology and Psychiatry Unit (E. Fazzi), ASST Civil Hospital, Department of Clinical and Experimental Sciences, University of Brescia; Child Neurology Department (E. Fiorini), Verona, Italy; Service de Genetique Clinique (M. Fradin, P.L., C.Q.), CLAD-Ouest, Hospital Sud, Rennes, France; Child Neurology Unit, Pediatric Department (C.F., C.S.), Azienda USL-IRCCS di Reggio Emilia; Department of Pediatric Neuroscience (T.G., R.S.), Fondazione IRCCS Istituto Neurologico Carlo Besta, Member of the ERN EpiCARE, Milan, Italy; Department of Epilepsy Genetics and Personalized Treatment (K.M.J., R.S.M.), The Danish Epilepsy Centre, Dianalund; Institute for Regional Health Services (K.M.J., R.S.M.), University of Southern Denmark, Odense; Unit of Pediatric Neurology and Pediatric Neurorehabilitation (S.L.), Woman-Mother-Child Department, Lausanne University Hospital CHUV, Switzerland; Unit of Neuroradiology (D.M.), Fondazione CNR/Regione Toscana G. Monasterio, Pisa; Pediatric Neurology Unit and Epilepsy Center (E.R., A.R.), Fatebenefratelli Hospital, Milan, Italy; KJF Klinik Josefinum GmbH (C.U.), Klinik für Kinder und Jugendliche, Neuropädiatrie, Augsburg, Germany; Department of Paediatric Clinical Epileptology, Sleep Disorders and Functional Neurology (A. Arzimanoglou), University Hospitals of Lyon, Coordinator of the ERN EpiCARE, France; and Pediatric Epilepsy Unit, Child Neurology Department (P.V.), Hospital San Juan de Dios, Member of the ERN EpiCARE and Universitat de Barcelona, Spain.

Objective: Aiming to detect associations between neuroradiologic and EEG evaluations and long-term clinical outcome in order to detect possible prognostic factors, a detailed clinical and neuroimaging characterization of 67 cases of Aicardi syndrome (AIC), collected through a multicenter collaboration, was performed.

Methods: Only patients who satisfied Sutton diagnostic criteria were included. Clinical outcome was assessed using gross motor function, manual ability, and eating and drinking ability classification systems. Brain imaging studies and statistical analysis were reviewed.

Results: Patients presented early-onset epilepsy, which evolved into drug-resistant seizures. AIC has a variable clinical course, leading to permanent disability in most cases; nevertheless, some cases presented residual motor abilities. Chorioretinal lacunae were present in 86.56% of our patients. Statistical analysis revealed correlations between MRI, EEG at onset, and clinical outcome. On brain imaging, 100% of the patients displayed corpus callosum malformations, 98% cortical dysplasia and nodular heterotopias, and 96.36% intracranial cysts (with similar rates of 2b and 2d). As well as demonstrating that posterior fossa abnormalities (found in 63.63% of cases) should also be considered a common feature in AIC, our study highlighted the presence (in 76.36%) of basal ganglia dysmorphisms (never previously reported).

Conclusion: The AIC neuroradiologic phenotype consists of a complex brain malformation whose presence should be considered central to the diagnosis. Basal ganglia dysmorphisms are frequently associated. Our work underlines the importance of MRI and EEG, both for correct diagnosis and as a factor for predicting long-term outcome.

Classification Of Evidence: This study provides Class II evidence that for patients with AIC, specific MRI abnormalities and EEG at onset are associated with clinical outcomes.
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http://dx.doi.org/10.1212/WNL.0000000000011237DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8055324PMC
March 2021

ATP7A mutation with occipital horns and distal motor neuropathy: A continuum.

Eur J Med Genet 2020 Dec 31;63(12):104087. Epub 2020 Oct 31.

Service de génétique, CLAD Ouest, CHU Rennes, Rennes, France; Service de génétique, CRDI, CHU Rennes, Rennes, France.

ATP7A-related copper transport disorders are classically separated in three pathologies according to their severity, all inherited in an X-linked recessive manner: Menkes disease (MD, OMIM #309400) which represent more than 90% of cases; occipital Horn Syndrome (OHS, OMIM #304150) and ATP7A-related distal motor neuropathy also named X-linked distal spinal muscular atrophy-3 (SMAX3, OMIM #300489) (Kennerson et al., 2010). Although there is no clear cut correlation between Cu and ceruloplasmin levels in ATP7A related disorders, these three entities probably represent a continuum partly depending on residual functional ATP7A protein (Møller, 2015). Thus far OHS and SMAX3 only partially overlap. In fact patients with OHS usually have no distal motor neuropathy signs but, on the other hand, occipital horns, which are the main sign of OHS, have not been described in SMAX3 patient. We describe here a patient bearing a missense ATP7A mutation with associated signs of distal motor neuropathy as well as occipital horns, confirming that OHS and SMAX3 are a continuum.
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http://dx.doi.org/10.1016/j.ejmg.2020.104087DOI Listing
December 2020

Next-generation sequencing in a series of 80 fetuses with complex cardiac malformations and/or heterotaxy.

Hum Mutat 2020 12 10;41(12):2167-2178. Epub 2020 Nov 10.

Centre de Génétique Humaine, CHU Franche-Comté, Besançon, France.

Herein, we report the screening of a large panel of genes in a series of 80 fetuses with congenital heart defects (CHDs) and/or heterotaxy and no cytogenetic anomalies. There were 49 males (61%/39%), with a family history in 28 cases (35%) and no parental consanguinity in 77 cases (96%). All fetuses had complex CHD except one who had heterotaxy and midline anomalies while 52 cases (65%) had heterotaxy in addition to CHD. Altogether, 29 cases (36%) had extracardiac and extra-heterotaxy anomalies. A pathogenic variant was found in 10/80 (12.5%) cases with a higher percentage in the heterotaxy group (8/52 cases, 15%) compared with the non-heterotaxy group (2/28 cases, 7%), and in 3 cases with extracardiac and extra-heterotaxy anomalies (3/29, 10%). The inheritance was recessive in six genes (DNAI1, GDF1, MMP21, MYH6, NEK8, and ZIC3) and dominant in two genes (SHH and TAB2). A homozygous pathogenic variant was found in three cases including only one case with known consanguinity. In conclusion, after removing fetuses with cytogenetic anomalies, next-generation sequencing discovered a causal variant in 12.5% of fetal cases with CHD and/or heterotaxy. Genetic counseling for future pregnancies was greatly improved. Surprisingly, unexpected consanguinity accounts for 20% of cases with identified pathogenic variants.
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http://dx.doi.org/10.1002/humu.24132DOI Listing
December 2020

Genotype-first in a cohort of 95 fetuses with multiple congenital abnormalities: when exome sequencing reveals unexpected fetal phenotype-genotype correlations.

J Med Genet 2021 06 30;58(6):400-413. Epub 2020 Jul 30.

Service d'Imagerie médicale, CHU de Besançon, Besançon, France.

Purpose: Molecular diagnosis based on singleton exome sequencing (sES) is particularly challenging in fetuses with multiple congenital abnormalities (MCA). Indeed, some studies reveal a diagnostic yield of about 20%, far lower than in live birth individuals showing developmental abnormalities (30%), suggesting that standard analyses, based on the correlation between clinical hallmarks described in postnatal syndromic presentations and genotype, may underestimate the impact of the genetic variants identified in fetal analyses.

Methods: We performed sES in 95 fetuses with MCA. Blind to phenotype, we applied a genotype-first approach consisting of combined analyses based on variants annotation and bioinformatics predictions followed by reverse phenotyping. Initially applied to OMIM-morbid genes, analyses were then extended to all genes. We complemented our approach by using reverse phenotyping, variant segregation analysis, bibliographic search and data sharing in order to establish the clinical significance of the prioritised variants.

Results: sES rapidly identified causal variant in 24/95 fetuses (25%), variants of unknown significance in OMIM genes in 8/95 fetuses (8%) and six novel candidate genes in 6/95 fetuses (6%).

Conclusions: This method, based on a genotype-first approach followed by reverse phenotyping, shed light on unexpected fetal phenotype-genotype correlations, emphasising the relevance of prenatal studies to reveal extreme clinical presentations associated with well-known Mendelian disorders.
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http://dx.doi.org/10.1136/jmedgenet-2020-106867DOI Listing
June 2021

Pathogenic WDFY3 variants cause neurodevelopmental disorders and opposing effects on brain size.

Brain 2019 09;142(9):2617-2630

GeneDx, Clinical Genomics, 207 Perry Parkway Gaithersburg, MD, USA.

The underpinnings of mild to moderate neurodevelopmental delay remain elusive, often leading to late diagnosis and interventions. Here, we present data on exome and genome sequencing as well as array analysis of 13 individuals that point to pathogenic, heterozygous, mostly de novo variants in WDFY3 (significant de novo enrichment P = 0.003) as a monogenic cause of mild and non-specific neurodevelopmental delay. Nine variants were protein-truncating and four missense. Overlapping symptoms included neurodevelopmental delay, intellectual disability, macrocephaly, and psychiatric disorders (autism spectrum disorders/attention deficit hyperactivity disorder). One proband presented with an opposing phenotype of microcephaly and the only missense-variant located in the PH-domain of WDFY3. Findings of this case are supported by previously published data, demonstrating that pathogenic PH-domain variants can lead to microcephaly via canonical Wnt-pathway upregulation. In a separate study, we reported that the autophagy scaffolding protein WDFY3 is required for cerebral cortical size regulation in mice, by controlling proper division of neural progenitors. Here, we show that proliferating cortical neural progenitors of human embryonic brains highly express WDFY3, further supporting a role for this molecule in the regulation of prenatal neurogenesis. We present data on Wnt-pathway dysregulation in Wdfy3-haploinsufficient mice, which display macrocephaly and deficits in motor coordination and associative learning, recapitulating the human phenotype. Consequently, we propose that in humans WDFY3 loss-of-function variants lead to macrocephaly via downregulation of the Wnt pathway. In summary, we present WDFY3 as a novel gene linked to mild to moderate neurodevelopmental delay and intellectual disability and conclude that variants putatively causing haploinsufficiency lead to macrocephaly, while an opposing pathomechanism due to variants in the PH-domain of WDFY3 leads to microcephaly.
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http://dx.doi.org/10.1093/brain/awz198DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6736092PMC
September 2019

Targeted panel sequencing establishes the implication of planar cell polarity pathway and involves new candidate genes in neural tube defect disorders.

Hum Genet 2019 Apr 5;138(4):363-374. Epub 2019 Mar 5.

Service de Génétique Moléculaire et Génomique, CHU Pontchaillou, 2 rue Henri le Guilloux, 35033, Rennes, France.

Neural tube defect disorders are developmental diseases that originate from an incomplete closure of the neural tube during embryogenesis. Despite high prevalence-1 out of 3000 live births-their etiology is not yet established and both environmental and genetic factors have been proposed, with a heritability rate of about 60%. Studies in mouse models as well as in human have further suggested a multifactorial pattern of inheritance for neural tube defect disorders. Here, we report results obtained from clinical diagnosis and NGS analysis of a cohort composed of 52 patients. Using a candidate gene panel approach, we identified variants in known genes of planar cell polarity (PCP) pathway, although with higher prevalence than previously reported. Our study also reveals variants in novel genes such as FREM2 and DISP1. Altogether, these results confirm the implication of the PCP genes and involve the FRAS/FREM2 complex and Sonic Hedgehog signaling as novel components in the appearance of NTDs.
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http://dx.doi.org/10.1007/s00439-019-01993-yDOI Listing
April 2019

Correction: IQSEC2-related encephalopathy in males and females: a comparative study including 37 novel patients.

Genet Med 2019 Aug;21(8):1897-1898

APHP, Service de genetique medicale, Necker- Enfants Malades Hospital, Imagine Institute, Paris Descartes University, Paris, France.

This Article was originally published under Nature Research's License to Publish, but has now been made available under a CC BY 4.0 license. The PDF and HTML versions of the Article have been modified accordingly.
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http://dx.doi.org/10.1038/s41436-018-0327-7DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7608434PMC
August 2019

IQSEC2-related encephalopathy in males and females: a comparative study including 37 novel patients.

Genet Med 2019 04 12;21(4):837-849. Epub 2018 Sep 12.

APHP, Service de genetique medicale, Necker-Enfants Malades Hospital, Imagine Institute, Paris Descartes University, Paris, France.

Purpose: Variants in IQSEC2, escaping X inactivation, cause X-linked intellectual disability with frequent epilepsy in males and females. We aimed to investigate sex-specific differences.

Methods: We collected the data of 37 unpublished patients (18 males and 19 females) with IQSEC2 pathogenic variants and 5 individuals with variants of unknown significance and reviewed published variants. We compared variant types and phenotypes in males and females and performed an analysis of IQSEC2 isoforms.

Results: IQSEC2 pathogenic variants mainly led to premature truncation and were scattered throughout the longest brain-specific isoform, encoding the synaptic IQSEC2/BRAG1 protein. Variants occurred de novo in females but were either de novo (2/3) or inherited (1/3) in males, with missense variants being predominantly inherited. Developmental delay and intellectual disability were overall more severe in males than in females. Likewise, seizures were more frequently observed and intractable, and started earlier in males than in females. No correlation was observed between the age at seizure onset and severity of intellectual disability or resistance to antiepileptic treatments.

Conclusion: This study provides a comprehensive overview of IQSEC2-related encephalopathy in males and females, and suggests that an accurate dosage of IQSEC2 at the synapse is crucial during normal brain development.
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http://dx.doi.org/10.1038/s41436-018-0268-1DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6752297PMC
April 2019

Expanding the phenotypic spectrum of variants in PDE4D/PRKAR1A: from acrodysostosis to acroscyphodysplasia.

Eur J Hum Genet 2018 11 13;26(11):1611-1622. Epub 2018 Jul 13.

Department of Medical Genetics, INSERM UMR 1163, Paris Descartes-Sorbonne Paris Cité University, IMAGINE Institute, Necker Enfants Malades Hospital, Paris, France.

Acrodysostosis (MIM 101800) is a dominantly inherited condition associating (1) skeletal features (short stature, facial dysostosis, and brachydactyly with cone-shaped epiphyses), (2) resistance to hormones and (3) possible intellectual disability. Acroscyphodysplasia (MIM 250215) is characterized by growth retardation, brachydactyly, and knee epiphyses embedded in cup-shaped metaphyses. We and others have identified PDE4D or PRKAR1A variants in acrodysostosis; PDE4D variants have been reported in three cases of acroscyphodysplasia. Our study aimed at reviewing the clinical and molecular findings in a cohort of 27 acrodysostosis and 5 acroscyphodysplasia cases. Among the acrodysostosis cases, we identified 9 heterozygous de novo PRKAR1A variants and 11 heterozygous PDE4D variants. The 7 patients without variants presented with symptoms of acrodysostosis (brachydactyly and cone-shaped epiphyses), but none had the characteristic facial dysostosis. In the acroscyphodysplasia cases, we identified 2 PDE4D variants. For 2 of the 3 negative cases, medical records revealed early severe infection, which has been described in some reports of acroscyphodysplasia. Subdividing our series of acrodysostosis based on the disease-causing gene, we confirmed genotype-phenotype correlations. Hormone resistance was consistently observed in patients carrying PRKAR1A variants, whereas no hormone resistance was observed in 9 patients with PDE4D variants. All patients with PDE4D variants shared characteristic facial features (midface hypoplasia with nasal hypoplasia) and some degree of intellectual disability. Our findings of PDE4D variants in two cases of acroscyphodysplasia support that PDE4D may be responsible for this severe skeletal dysplasia. We eventually emphasize the importance of some specific assessments in the long-term follow up, including cardiovascular and thromboembolic risk factors.
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http://dx.doi.org/10.1038/s41431-018-0135-1DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6189044PMC
November 2018

Fetal cerebral hemorrhage due to X-linked GATA1 gene mutation.

Prenat Diagn 2018 09 24;38(10):772-778. Epub 2018 Jul 24.

Unit of Fetal Pathology, Antoine Béclère Hospital, Clamart, France.

We report a multiplex family with a GATA1 gene mutation responsible for a massive fetal cerebral hemorrhage occurring at 36 weeks. Two other stillbirth cousins presented with fetal hydrops and congenital hemochromatosis' phenotype at 37 and 12 weeks of gestation. Molecular screening revealed the presence of a c.613G>A pathogenic allelic variation in exon 4 of GATA1 gene in the 3 male siblings and their carrier mothers. The diagnosis of a GATA1 gene mutation may be suspected in cases of male fetuses with intracerebral bleeding, particularly if a history of prior fetal loss(es) and mild maternal thrombocytopenia are also present.
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http://dx.doi.org/10.1002/pd.5320DOI Listing
September 2018

Loss of function IFT27 variants associated with an unclassified lethal fetal ciliopathy with renal agenesis.

Am J Med Genet A 2018 07 27;176(7):1610-1613. Epub 2018 Apr 27.

Unité d'Embryofoetopathologie, Service d'Histologie-Embryologie-Cytogénétique, Hôpital Necker-Enfants Malades, Assistance Publique - Hôpitaux de Paris (AP-HP), Paris, France.

Ciliopathies comprise a group of clinically heterogeneous and overlapping disorders with a wide spectrum of phenotypes ranging from prenatal lethality to adult-onset disorders. Pathogenic variants in more than 100 ciliary protein-encoding genes have been described, most notably those involved in intraflagellar transport (IFT) which comprises two protein complexes, responsible for retrograde (IFT-A) and anterograde transport (IFT-B). Here we describe a fetus with an unclassified severe ciliopathy phenotype including short ribs, polydactyly, bilateral renal agenesis, and imperforate anus, with compound heterozygosity for c.118_125del, p.(Thr40Glyfs*11) and a c.352 +1G > T in IFT27, which encodes a small GTPase component of the IFT-B complex. We conclude that bilateral renal agenesis is a rare feature of this severe ciliopathy and this report highlights the phenotypic overlap of Pallister-Hall syndrome and ciliopathies. The phenotype in patients with IFT27 gene variants is wide ranging from Bardet-Biedl syndrome to a lethal phenotype.
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http://dx.doi.org/10.1002/ajmg.a.38685DOI Listing
July 2018

Diagnostic strategy in segmentation defect of the vertebrae: a retrospective study of 73 patients.

J Med Genet 2018 Jun 19;55(6):422-429. Epub 2018 Feb 19.

Service de Génétique, Hôpital de Mulhouse, Mulhouse, France.

Background: Segmentation defects of the vertebrae (SDV) are non-specific features found in various syndromes. The molecular bases of SDV are not fully elucidated due to the wide range of phenotypes and classification issues. The genes involved are in the Notch signalling pathway, which is a key system in somitogenesis. Here we report on mutations identified in a diagnosis cohort of SDV. We focused on spondylocostal dysostosis (SCD) and the phenotype of these patients in order to establish a diagnostic strategy when confronted with SDV.

Patients And Methods: We used DNA samples from a cohort of 73 patients and performed targeted sequencing of the five known SCD-causing genes (, , , and ) in the first 48 patients and whole-exome sequencing (WES) in 28 relevant patients.

Results: Ten diagnoses, including four biallelic variants in , two biallelic variants in and , and one in and , were made with the gene panel, and two diagnoses, including biallelic variants in and one variant in were made by WES. The diagnostic yield of the gene panel was 10/73 (13.7%) in the global cohort but 8/10 (80%) in the subgroup meeting the SCD criteria; the diagnostic yield of WES was 2/28 (8%).

Conclusion: After negative array CGH, targeted sequencing of the five known SCD genes should only be performed in patients who meet the diagnostic criteria of SCD. The low proportion of candidate genes identified by WES in our cohort suggests the need to consider more complex genetic architectures in cases of SDV.
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http://dx.doi.org/10.1136/jmedgenet-2017-104939DOI Listing
June 2018

A framework to identify contributing genes in patients with Phelan-McDermid syndrome.

NPJ Genom Med 2017 23;2:32. Epub 2017 Oct 23.

Genetics Unit, CHU Estaing, Clermont-Ferrand, France.

Phelan-McDermid syndrome (PMS) is characterized by a variety of clinical symptoms with heterogeneous degrees of severity, including intellectual disability (ID), absent or delayed speech, and autism spectrum disorders (ASD). It results from a deletion of the distal part of chromosome 22q13 that in most cases includes the gene. is considered a major gene for PMS, but the factors that modulate the severity of the syndrome remain largely unknown. In this study, we investigated 85 patients with different 22q13 rearrangements (78 deletions and 7 duplications). We first explored the clinical features associated with PMS, and provide evidence for frequent corpus callosum abnormalities in 28% of 35 patients with brain imaging data. We then mapped several candidate genomic regions at the 22q13 region associated with high risk of clinical features, and suggest a second locus at 22q13 associated with absence of speech. Finally, in some cases, we identified additional clinically relevant copy-number variants (CNVs) at loci associated with ASD, such as 16p11.2 and 15q11q13, which could modulate the severity of the syndrome. We also report an inherited deletion transmitted to five affected daughters by a mother without ID nor ASD, suggesting that some individuals could compensate for such mutations. In summary, we shed light on the genotype-phenotype relationship of patients with PMS, a step towards the identification of compensatory mechanisms for a better prognosis and possibly treatments of patients with neurodevelopmental disorders.
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http://dx.doi.org/10.1038/s41525-017-0035-2DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5677962PMC
October 2017

Phenotype and genotype analysis of a French cohort of 119 patients with CHARGE syndrome.

Am J Med Genet C Semin Med Genet 2017 12 27;175(4):417-430. Epub 2017 Nov 27.

Service de Génétique, CHU de Lyon, Bron, France.

CHARGE syndrome (CS) is a genetic disorder whose first description included Coloboma, Heart disease, Atresia of choanae, Retarded growth and development, Genital hypoplasia, and Ear anomalies and deafness, most often caused by a genetic mutation in the CHD7 gene. Two features were then added: semicircular canal anomalies and arhinencephaly/olfactory bulb agenesis, with classification of typical, partial, or atypical forms on the basis of major and minor clinical criteria. The detection rate of a pathogenic variant in the CHD7 gene varies from 67% to 90%. To try to have an overview of this heterogenous clinical condition and specify a genotype-phenotype relation, we conducted a national study of phenotype and genotype in 119 patients with CS. Selected clinical diagnostic criteria were from Verloes (2005), updated by Blake & Prasad (). Besides obtaining a detailed clinical description, when possible, patients underwent a full ophthalmologic examination, audiometry, temporal bone CT scan, gonadotropin analysis, and olfactory-bulb MRI. All patients underwent CHD7 sequencing and MLPA analysis. We found a pathogenic CHD7 variant in 83% of typical CS cases and 58% of atypical cases. Pathogenic variants in the CHD7 gene were classified by the expected impact on the protein. In all, 90% of patients had a typical form of CS and 10% an atypical form. The most frequent features were deafness/semicircular canal hypoplasia (94%), pituitary defect/hypogonadism (89%), external ear anomalies (87%), square-shaped face (81%), and arhinencephaly/anosmia (80%). Coloboma (73%), heart defects (65%), and choanal atresia (43%) were less frequent.
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http://dx.doi.org/10.1002/ajmg.c.31591DOI Listing
December 2017

Fetal costello syndrome with neuromuscular spindles excess and p.Gly12Val HRAS mutation.

Eur J Med Genet 2017 Jul 25;60(7):395-398. Epub 2017 Apr 25.

Service d'Anatomopathologie, CHU Hôpital Morvan, Brest, France, EA 4685 LNB UBO, Brest, France.

Costello syndrome (CS) is a rare multiple congenital disorder caused by activating germline mutations in HRAS gene and is characterized by coarse facial features, severe feeding difficulties, failure to thrive, mild to severe intellectual disability, severe postnatal growth retardation, cardiac abnormalities or cancer predisposition. Phenotypic spectrum associated with HRAS mutations is broad, ranging from attenuated CS phenotype to neonatal and lethal forms with limited genotype-phenotype correlations. Congenital myopathy with neuromuscular spindle excess has been rarely described in the literature. We report a new severe fetal case of CS with distal arthrogryposis due to neuromuscular spindle excess, confirmed by the detection of the p.Gly12Val mutation in HRAS gene. This case emphasizes the fact that HRAS is the only gene responsible for neuromuscular spindle excess, underlines a correlation between p.Gly12Val mutation and severe CS phenotype and points out the importance of a muscle biopsy performed according to the suitable procedure in neuromuscular disorders for any fetal arthrogryposis.
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http://dx.doi.org/10.1016/j.ejmg.2017.03.014DOI Listing
July 2017

De novo TUBB2B mutation causes fetal akinesia deformation sequence with microlissencephaly: An unusual presentation of tubulinopathy.

Eur J Med Genet 2016 Apr 28;59(4):249-56. Epub 2015 Dec 28.

Inserm, U1016, Institut Cochin, Paris, France; CNRS, UMR8104, Paris, France; Paris Descartes - Sorbonne Paris Cité University, Imagine Institute, Paris, France.

Tubulinopathies are increasingly emerging major causes underlying complex cerebral malformations, particularly in case of microlissencephaly often associated with hypoplastic or absent corticospinal tracts. Fetal akinesia deformation sequence (FADS) refers to a clinically and genetically heterogeneous group of disorders with congenital malformations related to impaired fetal movement. We report on an early foetal case with FADS and microlissencephaly due to TUBB2B mutation. Neuropathological examination disclosed virtually absent cortical lamination, foci of neuronal overmigration into the leptomeningeal spaces, corpus callosum agenesis, cerebellar and brainstem hypoplasia and extremely severe hypoplasia of the spinal cord with no anterior and posterior horns and almost no motoneurons. At the cellular level, the p.Cys239Phe TUBB2B mutant leads to tubulin heterodimerization impairment, decreased ability to incorporate into the cytoskeleton, microtubule dynamics alteration, with an accelerated rate of depolymerization. To our knowledge, this is the first case of microlissencephaly to be reported presenting with a so severe and early form of FADS, highlighting the importance of tubulin mutation screening in the context of FADS with microlissencephaly.
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http://dx.doi.org/10.1016/j.ejmg.2015.12.007DOI Listing
April 2016

Karyotype is not dead (yet)!

Eur J Med Genet 2016 Jan 10;59(1):11-5. Epub 2015 Dec 10.

Laboratoire de Cytogénétique et Biologie Cellulaire, CHU Pontchaillou, Rennes, France; CNRS UMR 6290 (IGDR), Université de Rennes 1, France. Electronic address:

Background: While array-comparative genomic hybridization (a-CGH) and next-generation sequencing (NGS or exome) technologies have swiftly spread throughout the medical field, karyotype has gradually lost its leading role among genetic tests. Several international guidelines recommend starting with a-CGH screening then going on with exome analysis when investigating a patient with intellectual disability (ID) and no precise clinical diagnosis. A-CGH and whole exome sequencing increase etiologic diagnoses rate up to 30% in case of ID. However, physicians have to deal with the lack of qualitative information of the genome. Especially, exome and a-CGH analysis fail to detect chromosomal rearrangements because breakpoints are either located in introns or not associated with a gain or loss of genetic material. If these technologies cannot easily identify chromosomal translocations or inversions which sometimes split a gene, karyotype can.

Discussion: For the 5 cases described, karyotype provided the right diagnosis for a Mendelian disease while molecular analysis remained unsuccessful. We conclude that when a Mendelian disease is strongly suggested clinically, if molecular analysis is normal, it could be very useful to carry out a karyotype in order to demonstrate a chromosomal rearrangement involving the targeted gene. If this gene is disrupted, the physician can confirm the suspected disease and give appropriate genetic counseling.

Summary: This article aims at keeping in mind that karyotype, this old-fashioned genetic tool, can still remain powerful and useful within some genetic issues. Even in this modern period of whole exome sequencing, young geneticists should know that karyotype remains a powerful and cheap technology, available throughout the world and can still do a lot for families.
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http://dx.doi.org/10.1016/j.ejmg.2015.11.016DOI Listing
January 2016

The expanding spectrum of COL2A1 gene variants IN 136 patients with a skeletal dysplasia phenotype.

Eur J Hum Genet 2016 07 2;24(7):992-1000. Epub 2015 Dec 2.

Département de Génétique et INSERM U781, Université Paris Descartes-Sorbonne Paris Cité, Fondation Imagine, Hôpital Necker-Enfants malades, AP-HP, Paris, France.

Heterozygous COL2A1 variants cause a wide spectrum of skeletal dysplasia termed type II collagenopathies. We assessed the impact of this gene in our French series. A decision tree was applied to select 136 probands (71 Stickler cases, 21 Spondyloepiphyseal dysplasia congenita cases, 11 Kniest dysplasia cases, and 34 other dysplasia cases) before molecular diagnosis by Sanger sequencing. We identified 66 different variants among the 71 positive patients. Among those patients, 18 belonged to multiplex families and 53 were sporadic. Most variants (38/44, 86%) were located in the triple helical domain of the collagen chain and glycine substitutions were mainly observed in severe phenotypes, whereas arginine to cysteine changes were more often encountered in moderate phenotypes. This series of skeletal dysplasia is one of the largest reported so far, adding 44 novel variants (15%) to published data. We have confirmed that about half of our Stickler patients (46%) carried a COL2A1 variant, and that the molecular spectrum was different across the phenotypes. To further address the question of genotype-phenotype correlation, we plan to screen our patients for other candidate genes using a targeted next-generation sequencing approach.
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http://dx.doi.org/10.1038/ejhg.2015.250DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5070901PMC
July 2016

Osteopathia striata with cranial sclerosis: when a fetal malformation syndrome reveals maternal pathology.

Prenat Diagn 2015 Feb 26;35(2):200-2. Epub 2014 Oct 26.

Service de Génétique Clinique, Centre de Référence Maladies Rares CLAD-Ouest, CHU Hôpital Sud, Rennes, France.

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http://dx.doi.org/10.1002/pd.4502DOI Listing
February 2015

Inversion duplication deletions involving the long arm of chromosome 13: phenotypic description of additional three fetuses and genotype-phenotype correlation.

Am J Med Genet A 2014 Oct 26;164A(10):2504-9. Epub 2014 Jun 26.

Department of Developmental Biology, AP-HP, Robert Debré University Hospital, Paris and Diderot University, Paris, France; Clinical Genetics Unit, Rennes Sud University Hospital, Rennes, France.

Inversion duplication and terminal deletion of the long arm of chromosome 13 (inv dup del 13q) is a rare chromosomal rearrangement: only five patients have been reported, mostly involving a ring chromosome 13. We report on additional three fetuses with pure inv dup del 13q: Patient 1 had macrosomia, enlarged kidneys, hypersegmented lungs, unilateral moderate ventriculomegaly, and a mild form of hand and feet preaxial polydactyly; Patient 2 had intrauterine growth retardation, widely spaced eyes, left microphthalmia, right anophthalmia, short nose, bilateral absent thumbs, cutaneous syndactyly of toes 4 and 5, bifid third metacarpal, a small left kidney, hyposegmented lungs, and partial agenesis of the corpus callosum; Patient 3 had widely spaced eyes, long and smooth philtrum, low-set ears, median notch in the upper alveolar ridge, bifid tongue, cutaneous syndactyly of toes 2 and 3, enlarged kidneys and pancreas, arhinencephaly, and partial agenesis of the corpus callosum. We compared the phenotypes of these patients to those previously reported for ring chromosome 13, pure 13q deletions and duplications. We narrowed some critical regions previously reported for lung, kidney and fetal growth, and for thumb, cerebral, and eye anomalies.
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http://dx.doi.org/10.1002/ajmg.a.36658DOI Listing
October 2014

Congenital mirror movements: mutational analysis of RAD51 and DCC in 26 cases.

Neurology 2014 Jun 7;82(22):1999-2002. Epub 2014 May 7.

From INSERM, U 975, and CNRS 7225-CRICM (A.M., C.D., O.T., D.B., I.L., M.V., A.B., E.R.), Département de Neurologie (A.M., M.V., E.R.), Fédération de Génétique, Département de Génétique et de Cytogénétique (C.D., A.B.), Banque d'ADN et de cellules (I.L.), Department of Biostatistics (J.-L.G.), and Centre d'Investigation Clinique Pitié Neurosciences 1422 (E.R.), Hôpital Pitié-Salpêtrière, AP-HP, Paris; Université Pierre et Marie Curie-Paris-6 (A.M., C.D., M.V., A.B., E.R.), UMR_S 975, Paris; Laboratoire de Génétique (F.R.), Groupe hospitalier Lariboisière-Fernand Widal, AP-HP, Paris; INSERM UMR_S740 (F.R.), Université Paris 7 Denis Diderot, Paris, France; Unit of Neurology (M.C., A.B.), Florence Health Authority, Italy; Génétique Médicale (P.B.), CHU Paris Nord, Hôpital Jean Verdier, Bondy, France; Department of Human Genetics (J.W.), University Medical Center Hamburg-Eppendorf, Hamburg, Germany; Institute of Neurogenetics (A.W.), University of Lübeck, Germany; Service de Neuropédiatrie (D.D.), Hôpital Trousseau, AP-HP, Paris, France; Unit of Neurology (M.R.), Villa Sofia-Cervello Hospital, Palermo; Department of Neuroscience (S.R.), Section of Neurology and Clinical Neurophysiology, Azienda Ospedaliera Universitaria of Siena, Italy; Neurologie et Pathologie du Mouvement (L.D.), Neurologie A, Hopital Salengro, Centre Hospitalier Universitaire, EA 1046, Lille, France; Pediatric Neurology and Metabolism (L.D.M.), Universitair Ziekenhuis Brussel, Belgium; James J. and Joan A. Gardner Family Center for Parkinson's disease and Movement Disorders (A.J.E.), University of Cincinnati Academic Health Center, Cincinnati, OH; IRCCS Fondazione Stella Maris (S.F.), Calambrone, Pisa, Italy; Department of Neurology (S.K.), University Hospital Würzburg, Germany; Service de Génétique Clinique (C.Q.), Hôpital Sud, Rennes, France; Institute for Human Genetics (S.R.-S.), Uniklinik RWTH Aachen, Germany; Service de Génétique (G.P.), CHU Clémenceau, Caen, F

Objective: We screened a large series of individuals with congenital mirror movements (CMM) for mutations in the 2 identified causative genes, DCC and RAD51.

Methods: We studied 6 familial and 20 simplex CMM cases. Each patient had a standardized neurologic assessment. Analysis of DCC and RAD51 coding regions included Sanger sequencing and a quantitative method allowing detection of micro rearrangements. We then compared the frequency of rare variants predicted to be pathogenic by either the PolyPhen-2 or the SIFT algorithm in our population and in the 4,300 controls of European origin on the Exome Variant Server.

Results: We found 3 novel truncating mutations of DCC that segregate with CMM in 4 of the 6 families. Among the 20 simplex cases, we found one exonic deletion of DCC, one DCC mutation leading to a frameshift, 5 missense variants in DCC, and 2 missense variants in RAD51. All 7 missense variants were predicted to be pathogenic by one or both algorithms. Statistical analysis showed that the frequency of variants predicted to be deleterious was significantly different between patients and controls (p < 0.001 for both RAD51 and DCC).

Conclusion: Mutations and variants in DCC and RAD51 are strongly associated with CMM, but additional genes causing CMM remain to be discovered.
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http://dx.doi.org/10.1212/WNL.0000000000000477DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4105259PMC
June 2014

New insights into genotype-phenotype correlation for GLI3 mutations.

Eur J Hum Genet 2015 Jan 16;23(1):92-102. Epub 2014 Apr 16.

Service de Génétique, Hospices Civils de Lyon, CHU de Lyon, France.

The phenotypic spectrum of GLI3 mutations includes autosomal dominant Greig cephalopolysyndactyly syndrome (GCPS) and Pallister-Hall syndrome (PHS). PHS was first described as a lethal condition associating hypothalamic hamartoma, postaxial or central polydactyly, anal atresia and bifid epiglottis. Typical GCPS combines polysyndactyly of hands and feet and craniofacial features. Genotype-phenotype correlations have been found both for the location and the nature of GLI3 mutations, highlighting the bifunctional nature of GLI3 during development. Here we report on the molecular and clinical study of 76 cases from 55 families with either a GLI3 mutation (49 GCPS and 21 PHS), or a large deletion encompassing the GLI3 gene (6 GCPS cases). Most of mutations are novel and consistent with the previously reported genotype-phenotype correlation. Our results also show a correlation between the location of the mutation and abnormal corpus callosum observed in some patients with GCPS. Fetal PHS observations emphasize on the possible lethality of GLI3 mutations and extend the phenotypic spectrum of malformations such as agnathia and reductional limbs defects. GLI3 expression studied by in situ hybridization during human development confirms its early expression in target tissues.
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http://dx.doi.org/10.1038/ejhg.2014.62DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4266745PMC
January 2015

Postnatal diagnosis of 9q interstitial imbalances involving PTCH1, resulting from a familial intrachromosomal insertion.

Eur J Med Genet 2014 Apr 31;57(5):195-9. Epub 2014 Jan 31.

Laboratoire de Cytogénétique et Biologie Cellulaire, CHU Pontchaillou, Rennes, France.

Insertions are rare chromosomal rearrangements resulting from a three breaks mechanism. The risk of chromosomal imbalance in the offspring is estimated to be 15-50%. We have identified a familial history of direct, paracentric intrachromosomal 9q insertion, balanced in healthy members. For intrachromosomal insertions, unbalanced products in the offspring are always recombinants and in our case, reciprocal deletion and duplication of the inserted segment (9q22.31-9q31.1) were observed. These imbalances involved several genes, including PTCH1. PTCH1 haploinsufficiency causes Gorlin syndrome, an autosomal dominant disorder usually linked to the gene mutation but sometimes due to a 9q deletion. Clinical findings are different in 9q deletions and duplications including PTCH1, notably concerning the predisposition to benign and malignant tumors reported in the Gorlin syndrome. Furthermore, some features may be reciprocal. This history of intrachromosomal insertion highlights the importance of morphological cytogenetic analyses to provide an accurate genetic counseling.
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http://dx.doi.org/10.1016/j.ejmg.2013.12.010DOI Listing
April 2014

Antenatal spectrum of CHARGE syndrome in 40 fetuses with CHD7 mutations.

J Med Genet 2012 Nov 28;49(11):698-707. Epub 2012 Sep 28.

INSERM U-781, Hôpital Necker-Enfants Malades, Paris, France.

Background: CHARGE syndrome is a rare, usually sporadic disorder of multiple congenital anomalies ascribed to a CHD7 gene mutation in 60% of cases. Although the syndrome is well characterised in children, only one series of 10 fetuses with CHARGE syndrome has been reported to date. Therefore, we performed a detailed clinicopathological survey in our series of fetuses with CHD7 mutations, now extended to 40 cases. CHARGE syndrome is increasingly diagnosed antenatally, but remains challenging in many instances.

Method: Here we report a retrospective study of 40 cases of CHARGE syndrome with a CHD7 mutation, including 10 previously reported fetuses, in which fetal or neonatal clinical, radiological and histopathological examinations were performed.

Results: Conversely to postnatal studies, the proportion of males is high in our series (male to female ratio 2.6:1) suggesting a greater severity in males. Features almost constant in fetuses were external ear anomalies, arhinencephaly and semicircular canal agenesis, while intrauterine growth retardation was never observed. Finally, except for one, all other mutations identified in our antenatal series were truncating, suggesting a possible phenotype-genotype correlation.

Conclusions: Clinical analysis allowed us to refine the clinical description of CHARGE syndrome in fetuses, describe some novel features and set up diagnostic criteria in order to help the diagnosis of CHARGE syndrome after termination of pregnancies following the detection of severe malformations.
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http://dx.doi.org/10.1136/jmedgenet-2012-100926DOI Listing
November 2012
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