1
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Abedini SS, Akhavantabasi S, Liang Y, Heng JIT, Alizadehsani R, Dehzangi I, Bauer DC, Alinejad-Rokny H. A critical review of the impact of candidate copy number variants on autism spectrum disorder. MUTATION RESEARCH. REVIEWS IN MUTATION RESEARCH 2024; 794:108509. [PMID: 38977176 DOI: 10.1016/j.mrrev.2024.108509] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/04/2023] [Revised: 04/14/2024] [Accepted: 07/02/2024] [Indexed: 07/10/2024]
Abstract
Autism spectrum disorder (ASD) is a complex neurodevelopmental disorder (NDD) influenced by genetic, epigenetic, and environmental factors. Recent advancements in genomic analysis have shed light on numerous genes associated with ASD, highlighting the significant role of both common and rare genetic mutations, as well as copy number variations (CNVs), single nucleotide polymorphisms (SNPs) and unique de novo variants. These genetic variations disrupt neurodevelopmental pathways, contributing to the disorder's complexity. Notably, CNVs are present in 10 %-20 % of individuals with autism, with 3 %-7 % detectable through cytogenetic methods. While the role of submicroscopic CNVs in ASD has been recently studied, their association with genomic loci and genes has not been thoroughly explored. In this review, we focus on 47 CNV regions linked to ASD, encompassing 1632 genes, including protein-coding genes and long non-coding RNAs (lncRNAs), of which 659 show significant brain expression. Using a list of ASD-associated genes from SFARI, we detect 17 regions harboring at least one known ASD-related protein-coding gene. Of the remaining 30 regions, we identify 24 regions containing at least one protein-coding gene with brain-enriched expression and a nervous system phenotype in mouse mutants, and one lncRNA with both brain-enriched expression and upregulation in iPSC to neuron differentiation. This review not only expands our understanding of the genetic diversity associated with ASD but also underscores the potential of lncRNAs in contributing to its etiology. Additionally, the discovered CNVs will be a valuable resource for future diagnostic, therapeutic, and research endeavors aimed at prioritizing genetic variations in ASD.
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Affiliation(s)
- Seyedeh Sedigheh Abedini
- UNSW BioMedical Machine Learning Lab (BML), The Graduate School of Biomedical Engineering, UNSW Sydney, Sydney, NSW 2052, Australia; School of Biotechnology & Biomolecular Sciences, UNSW Sydney, Sydney, NSW 2052, Australia
| | - Shiva Akhavantabasi
- Department of Molecular Biology and Genetics, Yeni Yuzyil University, Istanbul, Turkey; Ghiaseddin Jamshid Kashani University, Andisheh University Town, Danesh Blvd, 3441356611, Abyek, Qazvin, Iran
| | - Yuheng Liang
- UNSW BioMedical Machine Learning Lab (BML), The Graduate School of Biomedical Engineering, UNSW Sydney, Sydney, NSW 2052, Australia
| | - Julian Ik-Tsen Heng
- Curtin Health Innovation Research Institute, Curtin University, Bentley 6845, Australia
| | - Roohallah Alizadehsani
- Institute for Intelligent Systems Research and Innovation (IISRI), Deakin University, Victoria, Australia
| | - Iman Dehzangi
- Center for Computational and Integrative Biology, Rutgers University, Camden, NJ 08102, USA; Department of Computer Science, Rutgers University, Camden, NJ 08102, USA
| | - Denis C Bauer
- Transformational Bioinformatics, Commonwealth Scientific and Industrial Research Organisation (CSIRO), Sydney, Australia; Applied BioSciences, Faculty of Science and Engineering, Macquarie University, Macquarie Park, Australia
| | - Hamid Alinejad-Rokny
- UNSW BioMedical Machine Learning Lab (BML), The Graduate School of Biomedical Engineering, UNSW Sydney, Sydney, NSW 2052, Australia; Tyree Institute of Health Engineering (IHealthE), UNSW Sydney, Sydney, NSW 2052, Australia.
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2
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Alsehli H, Alshahrani SM, Alzahrani S, Ababneh F, Alharbi NM, Alarfaj N, Baarmah D. Fetal and neonatal outcomes of posterior fossa anomalies: a retrospective cohort study. Sci Rep 2024; 14:8411. [PMID: 38600369 PMCID: PMC11006671 DOI: 10.1038/s41598-024-59163-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2023] [Accepted: 04/08/2024] [Indexed: 04/12/2024] Open
Abstract
The primary aim of this study was to estimate the incidence of posterior fossa anomalies (PFA) and assess the associated outcomes in King Abdulaziz Medical City (KAMC), Riyadh. All fetuses diagnosed by prenatal ultrasound with PFA from 2017 to 2021 in KAMC were analyzed retrospectively. PFA included Dandy-Walker malformation (DWM), mega cisterna magna (MCM), Blake's pouch cyst (BPC), and isolated vermian hypoplasia (VH). The 65 cases of PFA were 41.5% DWM, 46.2% MCM, 10.8% VH, and 1.5% BPC. The annual incidence rates were 2.48, 2.64, 4.41, 8.75, and 1.71 per 1000 anatomy scans for 2017, 2018, 2019, 2020, and 2021, respectively. Infants with DWM appeared to have a higher proportion of associated central nervous system (CNS) abnormalities (70.4% vs. 39.5%; p-value = 0.014) and seizures than others (45% vs. 17.9%; p-value = 0.041). Ten patients with abnormal genetic testing showed a single gene mutation causing CNS abnormalities, including a pathogenic variant in MPL, C5orf42, ISPD, PDHA1, PNPLA8, JAM3, COL18A1, and a variant of uncertain significance in the PNPLA8 gene. Our result showed that the most common PFA is DWM and MCM. The autosomal recessive pathogenic mutation is the major cause of genetic disease in Saudi patients diagnosed with PFA.
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Affiliation(s)
- Hanan Alsehli
- King Saud Bin Abdulaziz University for Health Sciences, Riyadh, Saudi Arabia.
- Department of Obstetrics and Gynecology, King Abdulaziz Medical City, Ministry of the National Guard-Health Affairs, Riyadh, Saudi Arabia.
- King Abdullah International Medical Research Center, Riyadh, Saudi Arabia.
| | - Saeed Mastour Alshahrani
- Department of Public Health, College of Applied Medical Sciences, King Khalid University, Abha, Saudi Arabia
| | - Shatha Alzahrani
- Department of Pediatric Neurology, King Abdullah Specialist Children Hospital, Ministry of the National Guard-Health Affairs, Riyadh, Saudi Arabia
| | - Farouq Ababneh
- Department of Genetics and Precision Medicine, King Abdullah Specialist Children Hospital, Ministry of the National Guard-Health Affairs, Riyadh, Saudi Arabia
- King Abdulaziz Medical City, Ministry of the National Guard-Health Affairs, Riyadh, Saudi Arabia
| | - Nawal Mashni Alharbi
- Department of Obstetrics and Gynecology, King Abdulaziz Medical City, Ministry of the National Guard-Health Affairs, Riyadh, Saudi Arabia
| | - Nassebah Alarfaj
- Department of Obstetrics and Gynecology, King Abdulaziz Medical City, Ministry of the National Guard-Health Affairs, Riyadh, Saudi Arabia
| | - Duaa Baarmah
- Department of Pediatrics, King Abdullah Bin Abdulaziz University Hospital, Princess Nourah Bint Abdulrahman University, Riyadh, Saudi Arabia
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3
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Lomeli C. S, Kristin B. A. Epigenetic regulation of craniofacial development and disease. Birth Defects Res 2024; 116:e2271. [PMID: 37964651 PMCID: PMC10872612 DOI: 10.1002/bdr2.2271] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2023] [Revised: 10/13/2023] [Accepted: 10/24/2023] [Indexed: 11/16/2023]
Abstract
BACKGROUND The formation of the craniofacial complex relies on proper neural crest development. The gene regulatory networks (GRNs) and signaling pathways orchestrating this process have been extensively studied. These GRNs and signaling cascades are tightly regulated as alterations to any stage of neural crest development can lead to common congenital birth defects, including multiple syndromes affecting facial morphology as well as nonsyndromic facial defects, such as cleft lip with or without cleft palate. Epigenetic factors add a hierarchy to the regulation of transcriptional networks and influence the spatiotemporal activation or repression of specific gene regulatory cascades; however less is known about their exact mechanisms in controlling precise gene regulation. AIMS In this review, we discuss the role of epigenetic factors during neural crest development, specifically during craniofacial development and how compromised activities of these regulators contribute to congenital defects that affect the craniofacial complex.
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Affiliation(s)
- Shull Lomeli C.
- Department of Craniofacial Biology, University of Colorado Anschutz Medical Campus, Aurora, CO, USA
| | - Artinger Kristin B.
- Department of Diagnostic and Biological Sciences, University of Minnesota School of Dentistry, Minneapolis, MN, USA
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4
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Martins M, Oliveira AR, Martins S, Vieira JP, Perdigão P, Fernandes AR, de Almeida LP, Palma PJ, Sequeira DB, Santos JMM, Duque F, Oliveira G, Cardoso AL, Peça J, Seabra CM. A Novel Genetic Variant in MBD5 Associated with Severe Epilepsy and Intellectual Disability: Potential Implications on Neural Primary Cilia. Int J Mol Sci 2023; 24:12603. [PMID: 37628781 PMCID: PMC10454663 DOI: 10.3390/ijms241612603] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2023] [Revised: 08/04/2023] [Accepted: 08/05/2023] [Indexed: 08/27/2023] Open
Abstract
Disruptions in the MBD5 gene have been linked with an array of clinical features such as global developmental delay, intellectual disability, autistic-like symptoms, and seizures, through unclear mechanisms. MBD5 haploinsufficiency has been associated with the disruption of primary cilium-related processes during early cortical development, and this has been reported in many neurodevelopmental disorders. In this study, we describe the clinical history of a 12-year-old child harboring a novel MBD5 rare variant and presenting psychomotor delay and seizures. To investigate the impact of MBD5 haploinsufficiency on neural primary cilia, we established a novel patient-derived cell line and used CRISPR-Cas9 technology to create an isogenic control. The patient-derived neural progenitor cells revealed a decrease in the length of primary cilia and in the total number of ciliated cells. This study paves the way to understanding the impact of MBD5 haploinsufficiency in brain development through its potential impact on neural primary cilia.
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Affiliation(s)
- Mariana Martins
- Center for Neuroscience and Cell Biology (CNC), University of Coimbra, 3004-504 Coimbra, Portugal
- Faculty of Pharmacy, University of Coimbra, 3000-548 Coimbra, Portugal
| | - Ana Rafaela Oliveira
- Center for Neuroscience and Cell Biology (CNC), University of Coimbra, 3004-504 Coimbra, Portugal
| | - Solange Martins
- Center for Neuroscience and Cell Biology (CNC), University of Coimbra, 3004-504 Coimbra, Portugal
- Institute for Interdisciplinary Research, University of Coimbra, 3030-789 Coimbra, Portugal
| | - José Pedro Vieira
- Neuropediatrics Unit, Central Lisbon Hospital Center, 1169-045 Lisbon, Portugal
| | - Pedro Perdigão
- Center for Neuroscience and Cell Biology (CNC), University of Coimbra, 3004-504 Coimbra, Portugal
- Institute for Interdisciplinary Research, University of Coimbra, 3030-789 Coimbra, Portugal
| | - Ana Rita Fernandes
- Center for Neuroscience and Cell Biology (CNC), University of Coimbra, 3004-504 Coimbra, Portugal
- Institute for Interdisciplinary Research, University of Coimbra, 3030-789 Coimbra, Portugal
| | - Luís Pereira de Almeida
- Center for Neuroscience and Cell Biology (CNC), University of Coimbra, 3004-504 Coimbra, Portugal
- Faculty of Pharmacy, University of Coimbra, 3000-548 Coimbra, Portugal
| | - Paulo Jorge Palma
- Institute of Endodontics, Faculty of Medicine, University of Coimbra, 3000-075 Coimbra, Portugal
- Center for Innovation and Research in Oral Sciences (CIROS), Faculty of Medicine, University of Coimbra, 3000-075 Coimbra, Portugal
| | - Diana Bela Sequeira
- Institute of Endodontics, Faculty of Medicine, University of Coimbra, 3000-075 Coimbra, Portugal
- Center for Innovation and Research in Oral Sciences (CIROS), Faculty of Medicine, University of Coimbra, 3000-075 Coimbra, Portugal
| | - João Miguel Marques Santos
- Institute of Endodontics, Faculty of Medicine, University of Coimbra, 3000-075 Coimbra, Portugal
- Center for Innovation and Research in Oral Sciences (CIROS), Faculty of Medicine, University of Coimbra, 3000-075 Coimbra, Portugal
| | - Frederico Duque
- University Clinic of Pediatrics, Faculty of Medicine, University of Coimbra, 3000-602 Coimbra, Portugal
- Child Developmental Center and Research and Clinical Training Center, Pediatric Hospital, Centro Hospitalar e Universitário de Coimbra (CHUC), 3000-602 Coimbra, Portugal
| | - Guiomar Oliveira
- University Clinic of Pediatrics, Faculty of Medicine, University of Coimbra, 3000-602 Coimbra, Portugal
- Child Developmental Center and Research and Clinical Training Center, Pediatric Hospital, Centro Hospitalar e Universitário de Coimbra (CHUC), 3000-602 Coimbra, Portugal
| | - Ana Luísa Cardoso
- Center for Neuroscience and Cell Biology (CNC), University of Coimbra, 3004-504 Coimbra, Portugal
- Institute for Interdisciplinary Research, University of Coimbra, 3030-789 Coimbra, Portugal
| | - João Peça
- Center for Neuroscience and Cell Biology (CNC), University of Coimbra, 3004-504 Coimbra, Portugal
- Department of Life Sciences, University of Coimbra, 3000-456 Coimbra, Portugal
| | - Catarina Morais Seabra
- Center for Neuroscience and Cell Biology (CNC), University of Coimbra, 3004-504 Coimbra, Portugal
- Institute for Interdisciplinary Research, University of Coimbra, 3030-789 Coimbra, Portugal
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5
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Guo M, Xie P, Liu S, Luan G, Li T. Epilepsy and Autism Spectrum Disorder (ASD): The Underlying Mechanisms and Therapy Targets Related to Adenosine. Curr Neuropharmacol 2023; 21:54-66. [PMID: 35794774 PMCID: PMC10193761 DOI: 10.2174/1570159x20666220706100136] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2021] [Revised: 03/23/2022] [Accepted: 04/26/2022] [Indexed: 02/04/2023] Open
Abstract
Epilepsy and autism spectrum disorder (ASD) are highly mutually comorbid, suggesting potential overlaps in genetic etiology, pathophysiology, and neurodevelopmental abnormalities. Adenosine, an endogenous anticonvulsant and neuroprotective neuromodulator of the brain, has been proved to affect the process of epilepsy and ASD. On the one hand, adenosine plays a crucial role in preventing the progression and development of epilepsy through adenosine receptordependent and -independent ways. On the other hand, adenosine signaling can not only regulate core symptoms but also improve comorbid disorders in ASD. Given the important role of adenosine in epilepsy and ASD, therapeutic strategies related to adenosine, including the ketogenic diet, neuromodulation therapy, and adenosine augmentation therapy, have been suggested for the arrangement of epilepsy and ASD. There are several proposals in this review. Firstly, it is necessary to further discuss the relationship between both diseases based on the comorbid symptoms and mechanisms of epilepsy and ASD. Secondly, it is important to explore the role of adenosine involved in epilepsy and ASD. Lastly, potential therapeutic value and clinical approaches of adenosine-related therapies in treating epilepsy and ASD need to be emphasized.
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Affiliation(s)
- Mengyi Guo
- Department of Brain Institute, Center of Epilepsy, Beijing Institute for Brain Disorders, Beijing Key Laboratory of Epilepsy Research, Sanbo Brain Hospital, Capital Medical University, Beijing 100093, China
- Department of Neurology, Center of Epilepsy, Beijing Institute for Brain Disorders, Sanbo Brain Hospital, Capital Medical University, Beijing 100093, China
| | - Pandeng Xie
- Department of Brain Institute, Center of Epilepsy, Beijing Institute for Brain Disorders, Beijing Key Laboratory of Epilepsy Research, Sanbo Brain Hospital, Capital Medical University, Beijing 100093, China
- Department of Neurology, Center of Epilepsy, Beijing Institute for Brain Disorders, Sanbo Brain Hospital, Capital Medical University, Beijing 100093, China
| | - Siqi Liu
- Department of Brain Institute, Center of Epilepsy, Beijing Institute for Brain Disorders, Beijing Key Laboratory of Epilepsy Research, Sanbo Brain Hospital, Capital Medical University, Beijing 100093, China
- Department of Neurology, Center of Epilepsy, Beijing Institute for Brain Disorders, Sanbo Brain Hospital, Capital Medical University, Beijing 100093, China
| | - Guoming Luan
- Department of Brain Institute, Center of Epilepsy, Beijing Institute for Brain Disorders, Beijing Key Laboratory of Epilepsy Research, Sanbo Brain Hospital, Capital Medical University, Beijing 100093, China
- Department of Neurology, Center of Epilepsy, Beijing Institute for Brain Disorders, Sanbo Brain Hospital, Capital Medical University, Beijing 100093, China
| | - Tianfu Li
- Department of Brain Institute, Center of Epilepsy, Beijing Institute for Brain Disorders, Beijing Key Laboratory of Epilepsy Research, Sanbo Brain Hospital, Capital Medical University, Beijing 100093, China
- Department of Neurology, Center of Epilepsy, Beijing Institute for Brain Disorders, Sanbo Brain Hospital, Capital Medical University, Beijing 100093, China
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6
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RINGs, DUBs and Abnormal Brain Growth-Histone H2A Ubiquitination in Brain Development and Disease. EPIGENOMES 2022; 6:epigenomes6040042. [PMID: 36547251 PMCID: PMC9778336 DOI: 10.3390/epigenomes6040042] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2022] [Revised: 11/29/2022] [Accepted: 11/30/2022] [Indexed: 12/03/2022] Open
Abstract
During mammalian neurodevelopment, signaling pathways converge upon transcription factors (TFs) to establish appropriate gene expression programmes leading to the production of distinct neural and glial cell types. This process is partially regulated by the dynamic modulation of chromatin states by epigenetic systems, including the polycomb group (PcG) family of co-repressors. PcG proteins form multi-subunit assemblies that sub-divide into distinct, yet functionally related families. Polycomb repressive complexes 1 and 2 (PRC1 and 2) modify the chemical properties of chromatin by covalently modifying histone tails via H2A ubiquitination (H2AK119ub1) and H3 methylation, respectively. In contrast to the PRCs, the Polycomb repressive deubiquitinase (PR-DUB) complex removes H2AK119ub1 from chromatin through the action of the C-terminal hydrolase BAP1. Genetic screening has identified several PcG mutations that are causally associated with a range of congenital neuropathologies associated with both localised and/or systemic growth abnormalities. As PRC1 and PR-DUB hold opposing functions to control H2AK119ub1 levels across the genome, it is plausible that such neurodevelopmental disorders arise through a common mechanism. In this review, we will focus on advancements regarding the composition and opposing molecular functions of mammalian PRC1 and PR-DUB, and explore how their dysfunction contributes to the emergence of neurodevelopmental disorders.
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7
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González-Ortega G, Llamas-Velasco S, Arteche-López A, Quesada-Espinosa JF, Puertas-Martín V, Gómez-Grande A, López-Álvarez J, Saiz Díaz RA, Lezana-Rosales JM, Villarejo-Galende A, González de la Aleja J. Early-Onset Dementia Associated with a Heterozygous, Nonsense, and de novo Variant in the MBD5 Gene. J Alzheimers Dis 2021; 84:73-78. [PMID: 34459404 DOI: 10.3233/jad-210648] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
The haploinsufficiency of the methyl-binding domain protein 5 (MBD5) gene has been identified as the determinant cause of the neuropsychiatric disorders grouped under the name MBD5-neurodevelopment disorders (MAND). MAND includes patients with intellectual disability, behavioral problems, and seizures with a static clinical course. However, a few reports have suggested regression. We describe a non-intellectually disabled female, with previous epilepsy and personality disorder, who developed early-onset dementia. The extensive etiologic study revealed a heterozygous nonsense de novo pathogenic variant in the MBD5 gene. This finding could support including the MBD5 gene in the study of patients with atypical early-onset dementia.
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Affiliation(s)
| | - Sara Llamas-Velasco
- Department of Neurology, Hospital Universitario 12 de Octubre, Madrid, Spain.,Group of Neurodegenerative Diseases, Instituto de Investigación Hospital 12 de Octubre (I+12), Madrid, Spain.,Biomedical Research Networking Center in Neurodegenerative diseases CIBERNED, Madrid, Spain
| | - Ana Arteche-López
- Department of Genetics, Hospital Universitario 12 de Octubre, Madrid, Spain
| | | | - Verónica Puertas-Martín
- Department of Neurology, Hospital Universitario 12 de Octubre, Madrid, Spain.,Universidad Internacional de La Rioja (UNIR), Logroño, Spain
| | - Adolfo Gómez-Grande
- Department of Nuclear Medicine, Hospital Universitario 12 de Octubre, Madrid, Spain
| | - Jorge López-Álvarez
- Department of Psychiatry, Hospital Universitario 12 de Octubre, Madrid, Spain
| | - Rosa Ana Saiz Díaz
- Department of Neurology, Hospital Universitario 12 de Octubre, Madrid, Spain.,Department of Medicine, School of Medicine, Complutense University, Madrid, Spain.,Epilepsy-EEG Unit, Hospital Universitario 12 de Octubre, Madrid, Spain
| | | | - Alberto Villarejo-Galende
- Department of Neurology, Hospital Universitario 12 de Octubre, Madrid, Spain.,Group of Neurodegenerative Diseases, Instituto de Investigación Hospital 12 de Octubre (I+12), Madrid, Spain.,Biomedical Research Networking Center in Neurodegenerative diseases CIBERNED, Madrid, Spain.,Department of Medicine, School of Medicine, Complutense University, Madrid, Spain
| | - Jesús González de la Aleja
- Department of Neurology, Hospital Universitario 12 de Octubre, Madrid, Spain.,Epilepsy-EEG Unit, Hospital Universitario 12 de Octubre, Madrid, Spain
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8
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Parodi C, Di Fede E, Peron A, Viganò I, Grazioli P, Castiglioni S, Finnell RH, Gervasini C, Vignoli A, Massa V. Chromatin Imbalance as the Vertex Between Fetal Valproate Syndrome and Chromatinopathies. Front Cell Dev Biol 2021; 9:654467. [PMID: 33959609 PMCID: PMC8093873 DOI: 10.3389/fcell.2021.654467] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2021] [Accepted: 04/01/2021] [Indexed: 12/12/2022] Open
Abstract
Prenatal exposure to valproate (VPA), an antiepileptic drug, has been associated with fetal valproate spectrum disorders (FVSD), a clinical condition including congenital malformations, developmental delay, intellectual disability as well as autism spectrum disorder, together with a distinctive facial appearance. VPA is a known inhibitor of histone deacetylase which regulates the chromatin state. Interestingly, perturbations of this epigenetic balance are associated with chromatinopathies, a heterogeneous group of Mendelian disorders arising from mutations in components of the epigenetic machinery. Patients affected from these disorders display a plethora of clinical signs, mainly neurological deficits and intellectual disability, together with distinctive craniofacial dysmorphisms. Remarkably, critically examining the phenotype of FVSD and chromatinopathies, they shared several overlapping features that can be observed despite the different etiologies of these disorders, suggesting the possible existence of a common perturbed mechanism(s) during embryonic development.
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Affiliation(s)
- Chiara Parodi
- Department of Health Sciences, Università degli Studi di Milano, Milan, Italy
| | - Elisabetta Di Fede
- Department of Health Sciences, Università degli Studi di Milano, Milan, Italy
| | - Angela Peron
- Human Pathology and Medical Genetics, ASST Santi Paolo e Carlo, San Paolo Hospital, Milan, Italy.,Child Neuropsychiatry Unit-Epilepsy Center, Department of Health Sciences, San Paolo Hospital, ASST Santi Paolo e Carlo, Università degli Studi di Milano, Milan, Italy.,Division of Medical Genetics, Department of Pediatrics, University of Utah School of Medicine, Salt Lake City, UT, United States
| | - Ilaria Viganò
- Department of Health Sciences, Università degli Studi di Milano, Milan, Italy
| | - Paolo Grazioli
- Department of Health Sciences, Università degli Studi di Milano, Milan, Italy
| | - Silvia Castiglioni
- Department of Health Sciences, Università degli Studi di Milano, Milan, Italy
| | - Richard H Finnell
- Departments of Molecular and Cellular Biology, Molecular and Human Genetics and Medicine, Center for Precision Environmental Health, Baylor College of Medicine, Houston, TX, United States
| | - Cristina Gervasini
- Department of Health Sciences, Università degli Studi di Milano, Milan, Italy.,"Aldo Ravelli" Center for Neurotechnology and Experimental Brain Therapeutics, Università degli Studi di Milano, Milan, Italy
| | - Aglaia Vignoli
- Department of Health Sciences, Università degli Studi di Milano, Milan, Italy
| | - Valentina Massa
- Department of Health Sciences, Università degli Studi di Milano, Milan, Italy.,"Aldo Ravelli" Center for Neurotechnology and Experimental Brain Therapeutics, Università degli Studi di Milano, Milan, Italy
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9
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Orrico A, Galli L, Rossi M, Cortesi A, Mazzi M, Caterino E. The Variable Expression of a Novel MBD5 Gene Frameshift Mutation in an Italian Family. Neuropediatrics 2021; 52:138-141. [PMID: 33374027 DOI: 10.1055/s-0040-1715633] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
Haploinsufficiency of the methyl-CpG-binding domain protein 5 (MBD5) gene is reported as a cause of an autosomal dominant type of cognitive disability (MRD1) and autism spectrum disorder through large deletions involving multiple genes or point mutations, ultimately leading to haploinsufficiency in both cases. However, relatively few reports have been published on the phenotypical spectrum resulting from point mutations.We report here on a novel heterozygous frameshift variant in the MBD5 gene [c.2579del; p.(Lys860Argfs*11)] in a family in which the typical signs associated with pathogenic variants were expressed with different degrees of severity in the clinical presentation of the carrier individuals.Our findings, adding a novel mutation to the mutational spectrum, further support the relevance of the MBD5 gene as one of the main molecular mechanisms involved in the pathogenesis of intellectual disability and contribute to the characterization of the genotype-phenotype correlations.
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Affiliation(s)
- Alfredo Orrico
- Inter-departmental Program for Molecular Diagnosis and Characterization of Pathogenic Mechanisms of Rare Genetic Diseases, Azienda Ospedaliero Universitaria Senese, Siena, Italy
- Clinical Genetics, ASL Toscana Sudest, Ospedale della Misericordia, Grosseto, Italy
| | - Lucia Galli
- Clinical Genetics, ASL Toscana Sudest, Ospedale della Misericordia, Grosseto, Italy
- Inter-departmental Program for Molecular Diagnosis and Characterization of Pathogenic Mechanisms of Rare Genetic Diseases, Azienda Ospedaliero Universitaria Senese, Siena, Italy
| | - Maja Rossi
- Molecular Diagnostic Laboratory, ASL Toscana Sudest, Ospedale della Misericordia, Grosseto, Italy
| | - Ambra Cortesi
- Molecular Diagnostic Laboratory, ASL Toscana Sudest, Ospedale della Misericordia, Grosseto, Italy
| | - Marta Mazzi
- Pathophysiology of Human Reproduction, ASL Toscana Sudest, Ospedale della Misericordia, Grosseto, Italy
| | - Ettore Caterino
- Neuropsychiatry Unit, ASL Toscana Sudest, UFSMIA Zona Amiata Grossetana, Grosseto, Italy
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10
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Myers KA, Marini C, Carvill GL, McTague A, Panetta J, Stutterd C, Stanley T, Marin S, Nguyen J, Barba C, Rosati A, Scott RH, Mefford HC, Guerrini R, Scheffer IE. Phenotypic Spectrum of Seizure Disorders in MBD5-Associated Neurodevelopmental Disorder. NEUROLOGY-GENETICS 2021; 7:e579. [PMID: 33912662 PMCID: PMC8075573 DOI: 10.1212/nxg.0000000000000579] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/22/2020] [Accepted: 02/11/2021] [Indexed: 11/25/2022]
Abstract
Objective To describe the phenotypic spectrum in patients with MBD5-associated neurodevelopmental disorder (MAND) and seizures; features of MAND include intellectual disability, epilepsy, psychiatric features of aggression and hyperactivity, and dysmorphic features including short stature and microcephaly, sleep disturbance, and ataxia. Methods We performed phenotyping on patients with MBD5 deletions, duplications, or point mutations and a history of seizures. Results Twenty-three patients with MAND and seizures were included. Median seizure onset age was 2.9 years (range 3 days–13 years). The most common seizure type was generalized tonic-clonic; focal, atypical absence, tonic, drop attacks, and myoclonic seizures occurred frequently. Seven children had convulsive status epilepticus and 3 nonconvulsive status epilepticus. Fever, viral illnesses, and hot weather provoked seizures. EEG studies in 17/21 patients were abnormal, typically showing slow generalized spike-wave and background slowing. Nine had drug-resistant epilepsy, although 3 eventually became seizure-free. All but one had moderate-to-severe developmental impairment. Epilepsy syndromes included Lennox-Gastaut syndrome, myoclonic-atonic epilepsy, and infantile spasms syndrome. Behavioral problems in 20/23 included aggression, self-injurious behavior, and sleep disturbance. Conclusions MBD5 disruption may be associated with severe early childhood-onset developmental and epileptic encephalopathy. Because neuropsychiatric dysfunction is common and severe, it should be an important focus of clinical management.
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Affiliation(s)
- Kenneth A Myers
- Research Institute of the McGill University Health Centre (K.M.), Montreal, PQ; Division of Child Neurology (K.M.), Department of Pediatrics, Montreal Children's Hospital, McGill University, Montreal, PQ; Department of Neurology & Neurosurgery (K.M.), Montreal Children's Hospital, McGill University, Montreal, PQ; Child Neurology and Psychiatry (C.M.), Salesi Pediatric Hospital, United Hospitals of Ancona, Ancona, Italy; Division of Genetic Medicine (G.L.C., J.N., H.C.M.), Department of Pediatrics, University of Washington, Seattle, WA; Department of Neurology (A.M.), Great Ormond Street Hospital for Children, London, UK; Developmental Neurosciences Programme (A.M.), UCL Great Ormond Street Institute of Child Health, London, UK; Neurology Network Melbourne (J.P.), Melbourne, Victoria, Australia; Murdoch Children's Research Institute (C.S., I.E.S.), Parkville, Victoria, Australia; Department of Paediatrics and Child Health (T.S.), School of Medicine and Health Sciences, University of Otago, Wellington, New Zealand; Division of Neurology (S.M.), Department of Pediatrics, Rady Faculty of Health Sciences, University of Manitoba, Winnipeg, Manitoba, Canada; Neurology Unit and Neurogenetic Laboratories (C.B., A.R., R.G.), Meyer Children's Hospital, Florence, Italy; Department of Clinical Genetics (R.H.S.), Great Ormond Street Hospital, London, UK; Epilepsy Research Centre (I.E.S.), Department of Medicine, The University of Melbourne, Austin Health, Heidelberg, Victoria, Australia; Department of Paediatrics (I.E.S.), Royal Children's Hospital, The University of Melbourne, Parkville, Victoria, Australia; and The Florey Institute of Neuroscience and Mental Health (I.E.S.), Heidelberg, Victoria, Australia
| | - Carla Marini
- Research Institute of the McGill University Health Centre (K.M.), Montreal, PQ; Division of Child Neurology (K.M.), Department of Pediatrics, Montreal Children's Hospital, McGill University, Montreal, PQ; Department of Neurology & Neurosurgery (K.M.), Montreal Children's Hospital, McGill University, Montreal, PQ; Child Neurology and Psychiatry (C.M.), Salesi Pediatric Hospital, United Hospitals of Ancona, Ancona, Italy; Division of Genetic Medicine (G.L.C., J.N., H.C.M.), Department of Pediatrics, University of Washington, Seattle, WA; Department of Neurology (A.M.), Great Ormond Street Hospital for Children, London, UK; Developmental Neurosciences Programme (A.M.), UCL Great Ormond Street Institute of Child Health, London, UK; Neurology Network Melbourne (J.P.), Melbourne, Victoria, Australia; Murdoch Children's Research Institute (C.S., I.E.S.), Parkville, Victoria, Australia; Department of Paediatrics and Child Health (T.S.), School of Medicine and Health Sciences, University of Otago, Wellington, New Zealand; Division of Neurology (S.M.), Department of Pediatrics, Rady Faculty of Health Sciences, University of Manitoba, Winnipeg, Manitoba, Canada; Neurology Unit and Neurogenetic Laboratories (C.B., A.R., R.G.), Meyer Children's Hospital, Florence, Italy; Department of Clinical Genetics (R.H.S.), Great Ormond Street Hospital, London, UK; Epilepsy Research Centre (I.E.S.), Department of Medicine, The University of Melbourne, Austin Health, Heidelberg, Victoria, Australia; Department of Paediatrics (I.E.S.), Royal Children's Hospital, The University of Melbourne, Parkville, Victoria, Australia; and The Florey Institute of Neuroscience and Mental Health (I.E.S.), Heidelberg, Victoria, Australia
| | - Gemma L Carvill
- Research Institute of the McGill University Health Centre (K.M.), Montreal, PQ; Division of Child Neurology (K.M.), Department of Pediatrics, Montreal Children's Hospital, McGill University, Montreal, PQ; Department of Neurology & Neurosurgery (K.M.), Montreal Children's Hospital, McGill University, Montreal, PQ; Child Neurology and Psychiatry (C.M.), Salesi Pediatric Hospital, United Hospitals of Ancona, Ancona, Italy; Division of Genetic Medicine (G.L.C., J.N., H.C.M.), Department of Pediatrics, University of Washington, Seattle, WA; Department of Neurology (A.M.), Great Ormond Street Hospital for Children, London, UK; Developmental Neurosciences Programme (A.M.), UCL Great Ormond Street Institute of Child Health, London, UK; Neurology Network Melbourne (J.P.), Melbourne, Victoria, Australia; Murdoch Children's Research Institute (C.S., I.E.S.), Parkville, Victoria, Australia; Department of Paediatrics and Child Health (T.S.), School of Medicine and Health Sciences, University of Otago, Wellington, New Zealand; Division of Neurology (S.M.), Department of Pediatrics, Rady Faculty of Health Sciences, University of Manitoba, Winnipeg, Manitoba, Canada; Neurology Unit and Neurogenetic Laboratories (C.B., A.R., R.G.), Meyer Children's Hospital, Florence, Italy; Department of Clinical Genetics (R.H.S.), Great Ormond Street Hospital, London, UK; Epilepsy Research Centre (I.E.S.), Department of Medicine, The University of Melbourne, Austin Health, Heidelberg, Victoria, Australia; Department of Paediatrics (I.E.S.), Royal Children's Hospital, The University of Melbourne, Parkville, Victoria, Australia; and The Florey Institute of Neuroscience and Mental Health (I.E.S.), Heidelberg, Victoria, Australia
| | - Amy McTague
- Research Institute of the McGill University Health Centre (K.M.), Montreal, PQ; Division of Child Neurology (K.M.), Department of Pediatrics, Montreal Children's Hospital, McGill University, Montreal, PQ; Department of Neurology & Neurosurgery (K.M.), Montreal Children's Hospital, McGill University, Montreal, PQ; Child Neurology and Psychiatry (C.M.), Salesi Pediatric Hospital, United Hospitals of Ancona, Ancona, Italy; Division of Genetic Medicine (G.L.C., J.N., H.C.M.), Department of Pediatrics, University of Washington, Seattle, WA; Department of Neurology (A.M.), Great Ormond Street Hospital for Children, London, UK; Developmental Neurosciences Programme (A.M.), UCL Great Ormond Street Institute of Child Health, London, UK; Neurology Network Melbourne (J.P.), Melbourne, Victoria, Australia; Murdoch Children's Research Institute (C.S., I.E.S.), Parkville, Victoria, Australia; Department of Paediatrics and Child Health (T.S.), School of Medicine and Health Sciences, University of Otago, Wellington, New Zealand; Division of Neurology (S.M.), Department of Pediatrics, Rady Faculty of Health Sciences, University of Manitoba, Winnipeg, Manitoba, Canada; Neurology Unit and Neurogenetic Laboratories (C.B., A.R., R.G.), Meyer Children's Hospital, Florence, Italy; Department of Clinical Genetics (R.H.S.), Great Ormond Street Hospital, London, UK; Epilepsy Research Centre (I.E.S.), Department of Medicine, The University of Melbourne, Austin Health, Heidelberg, Victoria, Australia; Department of Paediatrics (I.E.S.), Royal Children's Hospital, The University of Melbourne, Parkville, Victoria, Australia; and The Florey Institute of Neuroscience and Mental Health (I.E.S.), Heidelberg, Victoria, Australia
| | - Julie Panetta
- Research Institute of the McGill University Health Centre (K.M.), Montreal, PQ; Division of Child Neurology (K.M.), Department of Pediatrics, Montreal Children's Hospital, McGill University, Montreal, PQ; Department of Neurology & Neurosurgery (K.M.), Montreal Children's Hospital, McGill University, Montreal, PQ; Child Neurology and Psychiatry (C.M.), Salesi Pediatric Hospital, United Hospitals of Ancona, Ancona, Italy; Division of Genetic Medicine (G.L.C., J.N., H.C.M.), Department of Pediatrics, University of Washington, Seattle, WA; Department of Neurology (A.M.), Great Ormond Street Hospital for Children, London, UK; Developmental Neurosciences Programme (A.M.), UCL Great Ormond Street Institute of Child Health, London, UK; Neurology Network Melbourne (J.P.), Melbourne, Victoria, Australia; Murdoch Children's Research Institute (C.S., I.E.S.), Parkville, Victoria, Australia; Department of Paediatrics and Child Health (T.S.), School of Medicine and Health Sciences, University of Otago, Wellington, New Zealand; Division of Neurology (S.M.), Department of Pediatrics, Rady Faculty of Health Sciences, University of Manitoba, Winnipeg, Manitoba, Canada; Neurology Unit and Neurogenetic Laboratories (C.B., A.R., R.G.), Meyer Children's Hospital, Florence, Italy; Department of Clinical Genetics (R.H.S.), Great Ormond Street Hospital, London, UK; Epilepsy Research Centre (I.E.S.), Department of Medicine, The University of Melbourne, Austin Health, Heidelberg, Victoria, Australia; Department of Paediatrics (I.E.S.), Royal Children's Hospital, The University of Melbourne, Parkville, Victoria, Australia; and The Florey Institute of Neuroscience and Mental Health (I.E.S.), Heidelberg, Victoria, Australia
| | - Chloe Stutterd
- Research Institute of the McGill University Health Centre (K.M.), Montreal, PQ; Division of Child Neurology (K.M.), Department of Pediatrics, Montreal Children's Hospital, McGill University, Montreal, PQ; Department of Neurology & Neurosurgery (K.M.), Montreal Children's Hospital, McGill University, Montreal, PQ; Child Neurology and Psychiatry (C.M.), Salesi Pediatric Hospital, United Hospitals of Ancona, Ancona, Italy; Division of Genetic Medicine (G.L.C., J.N., H.C.M.), Department of Pediatrics, University of Washington, Seattle, WA; Department of Neurology (A.M.), Great Ormond Street Hospital for Children, London, UK; Developmental Neurosciences Programme (A.M.), UCL Great Ormond Street Institute of Child Health, London, UK; Neurology Network Melbourne (J.P.), Melbourne, Victoria, Australia; Murdoch Children's Research Institute (C.S., I.E.S.), Parkville, Victoria, Australia; Department of Paediatrics and Child Health (T.S.), School of Medicine and Health Sciences, University of Otago, Wellington, New Zealand; Division of Neurology (S.M.), Department of Pediatrics, Rady Faculty of Health Sciences, University of Manitoba, Winnipeg, Manitoba, Canada; Neurology Unit and Neurogenetic Laboratories (C.B., A.R., R.G.), Meyer Children's Hospital, Florence, Italy; Department of Clinical Genetics (R.H.S.), Great Ormond Street Hospital, London, UK; Epilepsy Research Centre (I.E.S.), Department of Medicine, The University of Melbourne, Austin Health, Heidelberg, Victoria, Australia; Department of Paediatrics (I.E.S.), Royal Children's Hospital, The University of Melbourne, Parkville, Victoria, Australia; and The Florey Institute of Neuroscience and Mental Health (I.E.S.), Heidelberg, Victoria, Australia
| | - Thorsten Stanley
- Research Institute of the McGill University Health Centre (K.M.), Montreal, PQ; Division of Child Neurology (K.M.), Department of Pediatrics, Montreal Children's Hospital, McGill University, Montreal, PQ; Department of Neurology & Neurosurgery (K.M.), Montreal Children's Hospital, McGill University, Montreal, PQ; Child Neurology and Psychiatry (C.M.), Salesi Pediatric Hospital, United Hospitals of Ancona, Ancona, Italy; Division of Genetic Medicine (G.L.C., J.N., H.C.M.), Department of Pediatrics, University of Washington, Seattle, WA; Department of Neurology (A.M.), Great Ormond Street Hospital for Children, London, UK; Developmental Neurosciences Programme (A.M.), UCL Great Ormond Street Institute of Child Health, London, UK; Neurology Network Melbourne (J.P.), Melbourne, Victoria, Australia; Murdoch Children's Research Institute (C.S., I.E.S.), Parkville, Victoria, Australia; Department of Paediatrics and Child Health (T.S.), School of Medicine and Health Sciences, University of Otago, Wellington, New Zealand; Division of Neurology (S.M.), Department of Pediatrics, Rady Faculty of Health Sciences, University of Manitoba, Winnipeg, Manitoba, Canada; Neurology Unit and Neurogenetic Laboratories (C.B., A.R., R.G.), Meyer Children's Hospital, Florence, Italy; Department of Clinical Genetics (R.H.S.), Great Ormond Street Hospital, London, UK; Epilepsy Research Centre (I.E.S.), Department of Medicine, The University of Melbourne, Austin Health, Heidelberg, Victoria, Australia; Department of Paediatrics (I.E.S.), Royal Children's Hospital, The University of Melbourne, Parkville, Victoria, Australia; and The Florey Institute of Neuroscience and Mental Health (I.E.S.), Heidelberg, Victoria, Australia
| | - Samantha Marin
- Research Institute of the McGill University Health Centre (K.M.), Montreal, PQ; Division of Child Neurology (K.M.), Department of Pediatrics, Montreal Children's Hospital, McGill University, Montreal, PQ; Department of Neurology & Neurosurgery (K.M.), Montreal Children's Hospital, McGill University, Montreal, PQ; Child Neurology and Psychiatry (C.M.), Salesi Pediatric Hospital, United Hospitals of Ancona, Ancona, Italy; Division of Genetic Medicine (G.L.C., J.N., H.C.M.), Department of Pediatrics, University of Washington, Seattle, WA; Department of Neurology (A.M.), Great Ormond Street Hospital for Children, London, UK; Developmental Neurosciences Programme (A.M.), UCL Great Ormond Street Institute of Child Health, London, UK; Neurology Network Melbourne (J.P.), Melbourne, Victoria, Australia; Murdoch Children's Research Institute (C.S., I.E.S.), Parkville, Victoria, Australia; Department of Paediatrics and Child Health (T.S.), School of Medicine and Health Sciences, University of Otago, Wellington, New Zealand; Division of Neurology (S.M.), Department of Pediatrics, Rady Faculty of Health Sciences, University of Manitoba, Winnipeg, Manitoba, Canada; Neurology Unit and Neurogenetic Laboratories (C.B., A.R., R.G.), Meyer Children's Hospital, Florence, Italy; Department of Clinical Genetics (R.H.S.), Great Ormond Street Hospital, London, UK; Epilepsy Research Centre (I.E.S.), Department of Medicine, The University of Melbourne, Austin Health, Heidelberg, Victoria, Australia; Department of Paediatrics (I.E.S.), Royal Children's Hospital, The University of Melbourne, Parkville, Victoria, Australia; and The Florey Institute of Neuroscience and Mental Health (I.E.S.), Heidelberg, Victoria, Australia
| | - John Nguyen
- Research Institute of the McGill University Health Centre (K.M.), Montreal, PQ; Division of Child Neurology (K.M.), Department of Pediatrics, Montreal Children's Hospital, McGill University, Montreal, PQ; Department of Neurology & Neurosurgery (K.M.), Montreal Children's Hospital, McGill University, Montreal, PQ; Child Neurology and Psychiatry (C.M.), Salesi Pediatric Hospital, United Hospitals of Ancona, Ancona, Italy; Division of Genetic Medicine (G.L.C., J.N., H.C.M.), Department of Pediatrics, University of Washington, Seattle, WA; Department of Neurology (A.M.), Great Ormond Street Hospital for Children, London, UK; Developmental Neurosciences Programme (A.M.), UCL Great Ormond Street Institute of Child Health, London, UK; Neurology Network Melbourne (J.P.), Melbourne, Victoria, Australia; Murdoch Children's Research Institute (C.S., I.E.S.), Parkville, Victoria, Australia; Department of Paediatrics and Child Health (T.S.), School of Medicine and Health Sciences, University of Otago, Wellington, New Zealand; Division of Neurology (S.M.), Department of Pediatrics, Rady Faculty of Health Sciences, University of Manitoba, Winnipeg, Manitoba, Canada; Neurology Unit and Neurogenetic Laboratories (C.B., A.R., R.G.), Meyer Children's Hospital, Florence, Italy; Department of Clinical Genetics (R.H.S.), Great Ormond Street Hospital, London, UK; Epilepsy Research Centre (I.E.S.), Department of Medicine, The University of Melbourne, Austin Health, Heidelberg, Victoria, Australia; Department of Paediatrics (I.E.S.), Royal Children's Hospital, The University of Melbourne, Parkville, Victoria, Australia; and The Florey Institute of Neuroscience and Mental Health (I.E.S.), Heidelberg, Victoria, Australia
| | - Carmen Barba
- Research Institute of the McGill University Health Centre (K.M.), Montreal, PQ; Division of Child Neurology (K.M.), Department of Pediatrics, Montreal Children's Hospital, McGill University, Montreal, PQ; Department of Neurology & Neurosurgery (K.M.), Montreal Children's Hospital, McGill University, Montreal, PQ; Child Neurology and Psychiatry (C.M.), Salesi Pediatric Hospital, United Hospitals of Ancona, Ancona, Italy; Division of Genetic Medicine (G.L.C., J.N., H.C.M.), Department of Pediatrics, University of Washington, Seattle, WA; Department of Neurology (A.M.), Great Ormond Street Hospital for Children, London, UK; Developmental Neurosciences Programme (A.M.), UCL Great Ormond Street Institute of Child Health, London, UK; Neurology Network Melbourne (J.P.), Melbourne, Victoria, Australia; Murdoch Children's Research Institute (C.S., I.E.S.), Parkville, Victoria, Australia; Department of Paediatrics and Child Health (T.S.), School of Medicine and Health Sciences, University of Otago, Wellington, New Zealand; Division of Neurology (S.M.), Department of Pediatrics, Rady Faculty of Health Sciences, University of Manitoba, Winnipeg, Manitoba, Canada; Neurology Unit and Neurogenetic Laboratories (C.B., A.R., R.G.), Meyer Children's Hospital, Florence, Italy; Department of Clinical Genetics (R.H.S.), Great Ormond Street Hospital, London, UK; Epilepsy Research Centre (I.E.S.), Department of Medicine, The University of Melbourne, Austin Health, Heidelberg, Victoria, Australia; Department of Paediatrics (I.E.S.), Royal Children's Hospital, The University of Melbourne, Parkville, Victoria, Australia; and The Florey Institute of Neuroscience and Mental Health (I.E.S.), Heidelberg, Victoria, Australia
| | - Anna Rosati
- Research Institute of the McGill University Health Centre (K.M.), Montreal, PQ; Division of Child Neurology (K.M.), Department of Pediatrics, Montreal Children's Hospital, McGill University, Montreal, PQ; Department of Neurology & Neurosurgery (K.M.), Montreal Children's Hospital, McGill University, Montreal, PQ; Child Neurology and Psychiatry (C.M.), Salesi Pediatric Hospital, United Hospitals of Ancona, Ancona, Italy; Division of Genetic Medicine (G.L.C., J.N., H.C.M.), Department of Pediatrics, University of Washington, Seattle, WA; Department of Neurology (A.M.), Great Ormond Street Hospital for Children, London, UK; Developmental Neurosciences Programme (A.M.), UCL Great Ormond Street Institute of Child Health, London, UK; Neurology Network Melbourne (J.P.), Melbourne, Victoria, Australia; Murdoch Children's Research Institute (C.S., I.E.S.), Parkville, Victoria, Australia; Department of Paediatrics and Child Health (T.S.), School of Medicine and Health Sciences, University of Otago, Wellington, New Zealand; Division of Neurology (S.M.), Department of Pediatrics, Rady Faculty of Health Sciences, University of Manitoba, Winnipeg, Manitoba, Canada; Neurology Unit and Neurogenetic Laboratories (C.B., A.R., R.G.), Meyer Children's Hospital, Florence, Italy; Department of Clinical Genetics (R.H.S.), Great Ormond Street Hospital, London, UK; Epilepsy Research Centre (I.E.S.), Department of Medicine, The University of Melbourne, Austin Health, Heidelberg, Victoria, Australia; Department of Paediatrics (I.E.S.), Royal Children's Hospital, The University of Melbourne, Parkville, Victoria, Australia; and The Florey Institute of Neuroscience and Mental Health (I.E.S.), Heidelberg, Victoria, Australia
| | - Richard H Scott
- Research Institute of the McGill University Health Centre (K.M.), Montreal, PQ; Division of Child Neurology (K.M.), Department of Pediatrics, Montreal Children's Hospital, McGill University, Montreal, PQ; Department of Neurology & Neurosurgery (K.M.), Montreal Children's Hospital, McGill University, Montreal, PQ; Child Neurology and Psychiatry (C.M.), Salesi Pediatric Hospital, United Hospitals of Ancona, Ancona, Italy; Division of Genetic Medicine (G.L.C., J.N., H.C.M.), Department of Pediatrics, University of Washington, Seattle, WA; Department of Neurology (A.M.), Great Ormond Street Hospital for Children, London, UK; Developmental Neurosciences Programme (A.M.), UCL Great Ormond Street Institute of Child Health, London, UK; Neurology Network Melbourne (J.P.), Melbourne, Victoria, Australia; Murdoch Children's Research Institute (C.S., I.E.S.), Parkville, Victoria, Australia; Department of Paediatrics and Child Health (T.S.), School of Medicine and Health Sciences, University of Otago, Wellington, New Zealand; Division of Neurology (S.M.), Department of Pediatrics, Rady Faculty of Health Sciences, University of Manitoba, Winnipeg, Manitoba, Canada; Neurology Unit and Neurogenetic Laboratories (C.B., A.R., R.G.), Meyer Children's Hospital, Florence, Italy; Department of Clinical Genetics (R.H.S.), Great Ormond Street Hospital, London, UK; Epilepsy Research Centre (I.E.S.), Department of Medicine, The University of Melbourne, Austin Health, Heidelberg, Victoria, Australia; Department of Paediatrics (I.E.S.), Royal Children's Hospital, The University of Melbourne, Parkville, Victoria, Australia; and The Florey Institute of Neuroscience and Mental Health (I.E.S.), Heidelberg, Victoria, Australia
| | - Heather C Mefford
- Research Institute of the McGill University Health Centre (K.M.), Montreal, PQ; Division of Child Neurology (K.M.), Department of Pediatrics, Montreal Children's Hospital, McGill University, Montreal, PQ; Department of Neurology & Neurosurgery (K.M.), Montreal Children's Hospital, McGill University, Montreal, PQ; Child Neurology and Psychiatry (C.M.), Salesi Pediatric Hospital, United Hospitals of Ancona, Ancona, Italy; Division of Genetic Medicine (G.L.C., J.N., H.C.M.), Department of Pediatrics, University of Washington, Seattle, WA; Department of Neurology (A.M.), Great Ormond Street Hospital for Children, London, UK; Developmental Neurosciences Programme (A.M.), UCL Great Ormond Street Institute of Child Health, London, UK; Neurology Network Melbourne (J.P.), Melbourne, Victoria, Australia; Murdoch Children's Research Institute (C.S., I.E.S.), Parkville, Victoria, Australia; Department of Paediatrics and Child Health (T.S.), School of Medicine and Health Sciences, University of Otago, Wellington, New Zealand; Division of Neurology (S.M.), Department of Pediatrics, Rady Faculty of Health Sciences, University of Manitoba, Winnipeg, Manitoba, Canada; Neurology Unit and Neurogenetic Laboratories (C.B., A.R., R.G.), Meyer Children's Hospital, Florence, Italy; Department of Clinical Genetics (R.H.S.), Great Ormond Street Hospital, London, UK; Epilepsy Research Centre (I.E.S.), Department of Medicine, The University of Melbourne, Austin Health, Heidelberg, Victoria, Australia; Department of Paediatrics (I.E.S.), Royal Children's Hospital, The University of Melbourne, Parkville, Victoria, Australia; and The Florey Institute of Neuroscience and Mental Health (I.E.S.), Heidelberg, Victoria, Australia
| | - Renzo Guerrini
- Research Institute of the McGill University Health Centre (K.M.), Montreal, PQ; Division of Child Neurology (K.M.), Department of Pediatrics, Montreal Children's Hospital, McGill University, Montreal, PQ; Department of Neurology & Neurosurgery (K.M.), Montreal Children's Hospital, McGill University, Montreal, PQ; Child Neurology and Psychiatry (C.M.), Salesi Pediatric Hospital, United Hospitals of Ancona, Ancona, Italy; Division of Genetic Medicine (G.L.C., J.N., H.C.M.), Department of Pediatrics, University of Washington, Seattle, WA; Department of Neurology (A.M.), Great Ormond Street Hospital for Children, London, UK; Developmental Neurosciences Programme (A.M.), UCL Great Ormond Street Institute of Child Health, London, UK; Neurology Network Melbourne (J.P.), Melbourne, Victoria, Australia; Murdoch Children's Research Institute (C.S., I.E.S.), Parkville, Victoria, Australia; Department of Paediatrics and Child Health (T.S.), School of Medicine and Health Sciences, University of Otago, Wellington, New Zealand; Division of Neurology (S.M.), Department of Pediatrics, Rady Faculty of Health Sciences, University of Manitoba, Winnipeg, Manitoba, Canada; Neurology Unit and Neurogenetic Laboratories (C.B., A.R., R.G.), Meyer Children's Hospital, Florence, Italy; Department of Clinical Genetics (R.H.S.), Great Ormond Street Hospital, London, UK; Epilepsy Research Centre (I.E.S.), Department of Medicine, The University of Melbourne, Austin Health, Heidelberg, Victoria, Australia; Department of Paediatrics (I.E.S.), Royal Children's Hospital, The University of Melbourne, Parkville, Victoria, Australia; and The Florey Institute of Neuroscience and Mental Health (I.E.S.), Heidelberg, Victoria, Australia
| | - Ingrid E Scheffer
- Research Institute of the McGill University Health Centre (K.M.), Montreal, PQ; Division of Child Neurology (K.M.), Department of Pediatrics, Montreal Children's Hospital, McGill University, Montreal, PQ; Department of Neurology & Neurosurgery (K.M.), Montreal Children's Hospital, McGill University, Montreal, PQ; Child Neurology and Psychiatry (C.M.), Salesi Pediatric Hospital, United Hospitals of Ancona, Ancona, Italy; Division of Genetic Medicine (G.L.C., J.N., H.C.M.), Department of Pediatrics, University of Washington, Seattle, WA; Department of Neurology (A.M.), Great Ormond Street Hospital for Children, London, UK; Developmental Neurosciences Programme (A.M.), UCL Great Ormond Street Institute of Child Health, London, UK; Neurology Network Melbourne (J.P.), Melbourne, Victoria, Australia; Murdoch Children's Research Institute (C.S., I.E.S.), Parkville, Victoria, Australia; Department of Paediatrics and Child Health (T.S.), School of Medicine and Health Sciences, University of Otago, Wellington, New Zealand; Division of Neurology (S.M.), Department of Pediatrics, Rady Faculty of Health Sciences, University of Manitoba, Winnipeg, Manitoba, Canada; Neurology Unit and Neurogenetic Laboratories (C.B., A.R., R.G.), Meyer Children's Hospital, Florence, Italy; Department of Clinical Genetics (R.H.S.), Great Ormond Street Hospital, London, UK; Epilepsy Research Centre (I.E.S.), Department of Medicine, The University of Melbourne, Austin Health, Heidelberg, Victoria, Australia; Department of Paediatrics (I.E.S.), Royal Children's Hospital, The University of Melbourne, Parkville, Victoria, Australia; and The Florey Institute of Neuroscience and Mental Health (I.E.S.), Heidelberg, Victoria, Australia
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Seabra CM, Aneichyk T, Erdin S, Tai DJC, De Esch CEF, Razaz P, An Y, Manavalan P, Ragavendran A, Stortchevoi A, Abad C, Young JI, Maciel P, Talkowski ME, Gusella JF. Transcriptional consequences of MBD5 disruption in mouse brain and CRISPR-derived neurons. Mol Autism 2020; 11:45. [PMID: 32503625 PMCID: PMC7275313 DOI: 10.1186/s13229-020-00354-1] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2019] [Accepted: 05/25/2020] [Indexed: 01/02/2023] Open
Abstract
BACKGROUND MBD5, encoding the methyl-CpG-binding domain 5 protein, has been proposed as a necessary and sufficient driver of the 2q23.1 microdeletion syndrome. De novo missense and protein-truncating variants from exome sequencing studies have directly implicated MBD5 in the etiology of autism spectrum disorder (ASD) and related neurodevelopmental disorders (NDDs). However, little is known concerning the specific function(s) of MBD5. METHODS To gain insight into the complex interactions associated with alteration of MBD5 in individuals with ASD and related NDDs, we explored the transcriptional landscape of MBD5 haploinsufficiency across multiple mouse brain regions of a heterozygous hypomorphic Mbd5+/GT mouse model, and compared these results to CRISPR-mediated mutations of MBD5 in human iPSC-derived neuronal models. RESULTS Gene expression analyses across three brain regions from Mbd5+/GT mice showed subtle transcriptional changes, with cortex displaying the most widespread changes following Mbd5 reduction, indicating context-dependent effects. Comparison with MBD5 reduction in human neuronal cells reinforced the context-dependence of gene expression changes due to MBD5 deficiency. Gene co-expression network analyses revealed gene clusters that were associated with reduced MBD5 expression and enriched for terms related to ciliary function. LIMITATIONS These analyses included a limited number of mouse brain regions and neuronal models, and the effects of the gene knockdown are subtle. As such, these results will not reflect the full extent of MBD5 disruption across human brain regions during early neurodevelopment in ASD, or capture the diverse spectrum of cell-type-specific changes associated with MBD5 alterations. CONCLUSIONS Our study points to modest and context-dependent transcriptional consequences of Mbd5 disruption in the brain. It also suggests a possible link between MBD5 and perturbations in ciliary function, which is an established pathogenic mechanism in developmental disorders and syndromes.
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Affiliation(s)
- Catarina M Seabra
- Molecular Neurogenetics Unit, Center for Genomic Medicine, Massachusetts General Hospital, Boston, MA, USA.,Program in Medical and Population Genetics, Broad Institute of MIT and Harvard Medical School, Boston, MA, USA.,GABBA Program - Institute of Biomedical Sciences Abel Salazar of the University of Porto, Porto, Portugal
| | - Tatsiana Aneichyk
- Molecular Neurogenetics Unit, Center for Genomic Medicine, Massachusetts General Hospital, Boston, MA, USA.,Program in Medical and Population Genetics, Broad Institute of MIT and Harvard Medical School, Boston, MA, USA.,Independent Data Lab UG, Munich, Germany
| | - Serkan Erdin
- Molecular Neurogenetics Unit, Center for Genomic Medicine, Massachusetts General Hospital, Boston, MA, USA.,Program in Medical and Population Genetics, Broad Institute of MIT and Harvard Medical School, Boston, MA, USA
| | - Derek J C Tai
- Molecular Neurogenetics Unit, Center for Genomic Medicine, Massachusetts General Hospital, Boston, MA, USA.,Program in Medical and Population Genetics, Broad Institute of MIT and Harvard Medical School, Boston, MA, USA.,Department of Neurology, Harvard Medical School, Boston, MA, USA
| | - Celine E F De Esch
- Molecular Neurogenetics Unit, Center for Genomic Medicine, Massachusetts General Hospital, Boston, MA, USA.,Program in Medical and Population Genetics, Broad Institute of MIT and Harvard Medical School, Boston, MA, USA.,Department of Neurology, Harvard Medical School, Boston, MA, USA
| | - Parisa Razaz
- Molecular Neurogenetics Unit, Center for Genomic Medicine, Massachusetts General Hospital, Boston, MA, USA.,Program in Medical and Population Genetics, Broad Institute of MIT and Harvard Medical School, Boston, MA, USA.,Department of Neurology, Harvard Medical School, Boston, MA, USA
| | - Yu An
- Molecular Neurogenetics Unit, Center for Genomic Medicine, Massachusetts General Hospital, Boston, MA, USA.,Human Phenome Institute, Fudan University, Shanghai, China
| | - Poornima Manavalan
- Molecular Neurogenetics Unit, Center for Genomic Medicine, Massachusetts General Hospital, Boston, MA, USA
| | - Ashok Ragavendran
- Molecular Neurogenetics Unit, Center for Genomic Medicine, Massachusetts General Hospital, Boston, MA, USA.,Program in Medical and Population Genetics, Broad Institute of MIT and Harvard Medical School, Boston, MA, USA.,Center for Computational Biology of Human Disease & Center for Computation and Visualization, Brown University, Providence, Rhode Island, USA
| | - Alexei Stortchevoi
- Molecular Neurogenetics Unit, Center for Genomic Medicine, Massachusetts General Hospital, Boston, MA, USA
| | - Clemer Abad
- Dr. John T. Macdonald Foundation Department of Human Genetics, University of Miami, Miami, FL, USA
| | - Juan I Young
- Dr. John T. Macdonald Foundation Department of Human Genetics, University of Miami, Miami, FL, USA
| | - Patricia Maciel
- Life and Health Sciences Research Institute (ICVS), School of Medicine, University of Minho, Braga, Portugal.,ICVS/3B's - PT Government Associate Laboratory, Braga, Guimarães, Portugal
| | - Michael E Talkowski
- Molecular Neurogenetics Unit, Center for Genomic Medicine, Massachusetts General Hospital, Boston, MA, USA.,Program in Medical and Population Genetics, Broad Institute of MIT and Harvard Medical School, Boston, MA, USA.,Department of Neurology, Harvard Medical School, Boston, MA, USA
| | - James F Gusella
- Molecular Neurogenetics Unit, Center for Genomic Medicine, Massachusetts General Hospital, Boston, MA, USA. .,Program in Medical and Population Genetics, Broad Institute of MIT and Harvard Medical School, Boston, MA, USA. .,Department of Genetics, Blavatnik Institute, Harvard Medical School, Boston, MA, USA. .,Harvard Stem Cell Institute, Harvard University, Cambridge, MA, USA.
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12
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Almuzzaini B, Alatwi NS, Alsaif S, Al Balwi MA. A novel interstitial deletion of chromosome 2q21.1-q23.3: Case report and literature review. Mol Genet Genomic Med 2020; 8:e1135. [PMID: 31989799 PMCID: PMC7196451 DOI: 10.1002/mgg3.1135] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2019] [Revised: 12/24/2019] [Accepted: 01/06/2020] [Indexed: 12/16/2022] Open
Abstract
Background Interstitial deletions of 2q are rare. Those that have been reported show varying clinical manifestations according to the size of the deletion and the genomic region involved. Method and Results We describe a preterm male harboring a novel interstitial deletion encompassing the 2q21.2‐q23.3 region of 2q, a deletion that has not been described previously. The patient had multiple congenital anomalies including agenesis of the corpus callosum, congenital cardiac defects, bilateral hydronephrosis, spontaneous intestinal perforation, hypospadias and cryptorchidism, sacral dimple and rocker‐bottom feet. Array comparative genomic hybridization (aCGH) analysis revealed a de novo >18 Mb deletion at 2q21.1–q23.3, a region that included (605802, 611472 and 604593) OMIM genes. Conclusion To the best of our knowledge this is the first report of a de novo interstitial deletion at 2q21.1–q23.3 in which haploinsufficiency of dose‐sensitive genes is shown to contribute to the patient's phenotype.
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Affiliation(s)
- Bader Almuzzaini
- Department of Medical Genomics Research, King Abdullah International Medical Research Center, Ministry of National Guard Health Affairs, Riyadh, Saudi Arabia.,Department of Pathology and Laboratory Medicine, King Abdulaziz Medical City, Ministry of National Guard Health Affairs, Riyadh, Saudi Arabia
| | - Nasser S Alatwi
- Department of Pathology and Laboratory Medicine, King Abdulaziz Medical City, Ministry of National Guard Health Affairs, Riyadh, Saudi Arabia.,College of Medicine, King Saud bin Abdulaziz University for Health Sciences, Riyadh, Saudi Arabia
| | - Saif Alsaif
- College of Medicine, King Saud bin Abdulaziz University for Health Sciences, Riyadh, Saudi Arabia.,Department of Neonatal Intensive Care Unit, King Abdulaziz Medical City, Ministry of National Guard Health Affairs, Riyadh, Saudi Arabia
| | - Mohammed A Al Balwi
- Department of Medical Genomics Research, King Abdullah International Medical Research Center, Ministry of National Guard Health Affairs, Riyadh, Saudi Arabia.,Department of Pathology and Laboratory Medicine, King Abdulaziz Medical City, Ministry of National Guard Health Affairs, Riyadh, Saudi Arabia.,College of Medicine, King Saud bin Abdulaziz University for Health Sciences, Riyadh, Saudi Arabia
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13
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Beygo J, Buiting K, Ramsden SC, Ellis R, Clayton-Smith J, Kanber D. Update of the EMQN/ACGS best practice guidelines for molecular analysis of Prader-Willi and Angelman syndromes. Eur J Hum Genet 2019; 27:1326-1340. [PMID: 31235867 PMCID: PMC6777528 DOI: 10.1038/s41431-019-0435-0] [Citation(s) in RCA: 37] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2018] [Revised: 03/20/2019] [Accepted: 05/07/2019] [Indexed: 11/23/2022] Open
Abstract
This article is an update of the best practice guidelines for the molecular analysis of Prader-Willi and Angelman syndromes published in 2010 in BMC Medical Genetics [1]. The update takes into account developments in terms of techniques, differential diagnoses and (especially) reporting standards. It highlights the advantages and disadvantages of each method and moreover, is meant to facilitate the interpretation of the obtained results - leading to improved standardised reports.
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Affiliation(s)
- Jasmin Beygo
- Institut für Humangenetik, Universitätsklinikum Essen, Universität Duisburg-Essen, Essen, Germany.
| | - Karin Buiting
- Institut für Humangenetik, Universitätsklinikum Essen, Universität Duisburg-Essen, Essen, Germany
| | - Simon C Ramsden
- Manchester Centre for Genomic Medicine, Manchester University Hospitals NHS Foundation Trust, Manchester Academic Health Sciences Centre, Manchester, UK
| | - Rachael Ellis
- Department of Medical Genetics, Yorkhill NHS Trust, Yorkhill Hospital, Glasgow, G3 8SJ, UK
| | - Jill Clayton-Smith
- Manchester Centre for Genomic Medicine, Manchester University Hospitals NHS Foundation Trust, Manchester Academic Health Sciences Centre, Manchester, UK
- Division of Evolution and Genomic Sciences School of Biological Sciences University of Manchester, Manchester, UK
| | - Deniz Kanber
- Institut für Humangenetik, Universitätsklinikum Essen, Universität Duisburg-Essen, Essen, Germany.
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14
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Verhoeven W, Egger J, Kipp J, Verheul‐ aan de Wiel J, Ockeloen C, Kleefstra T, Pfundt R. A novel MBD5 mutation in an intellectually disabled adult female patient with epilepsy: Suggestive of early onset dementia? Mol Genet Genomic Med 2019; 7:e849. [PMID: 31290275 PMCID: PMC6687664 DOI: 10.1002/mgg3.849] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2019] [Revised: 05/27/2019] [Accepted: 06/05/2019] [Indexed: 11/12/2022] Open
Abstract
BACKGROUND The minimal critical region in 2q23.1 deletion syndrome comprises one gene only, that is, the methyl-CpG-binding domain protein 5 (MBD5) gene. Since the phenotypes of patients with deletions, duplications or pathogenic variants of MBD5 show considerable overlap, the term MBD5-associated neurodevelopmental disorder (MAND) was proposed. These syndromes are characterized by intellectual disability, seizures of any kind and symptoms from the autism spectrum. In a very limited number of patients, MAND may be associated with regression starting either at early infancy or at midlife. METHODS The present paper describes a severely intellectually disabled autistic female with therapy resistant complex partial epilepsy starting at her 16the with gradual cognitive and behavioral regression towards her sixth decade. RESULTS Cognitive and behavioral regression occurred towards the patient's sixth decade. Exome sequencing disclosed a novel heterozygous pathogenic frameshift mutation of MBD5 that was considered to be causative for the combination of intellectual disability, treatment-resistant epilepsy and autism. CONCLUSION The presented patient is the second with a pathogenic MBD5 mutation in whom the course of disease is suggestive of early onset dementia starting in her fifth decade. These findings stress the importance of exome sequencing, also in elderly intellectually disabled patients, particularly in those with autism.
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Affiliation(s)
- Willem Verhoeven
- Centre of Excellence for NeuropsychiatryVincent van Gogh Institute for PsychiatryVenraythe Netherlands
- Department of PsychiatryErasmus University Medical CentreRotterdamthe Netherlands
| | - Jos Egger
- Centre of Excellence for NeuropsychiatryVincent van Gogh Institute for PsychiatryVenraythe Netherlands
- Donders Institute for Brain, Cognition and BehaviourRadboud UniversityNijmegenthe Netherlands
- Stevig Specialized and Forensic Care for People with Intellectual Disabilities, DichterbijOostrumthe Netherlands
| | - Janneke Kipp
- ASVZ Institutes for Intellectual DisabilitiesLeerdamthe Netherlands
| | | | - Charlotte Ockeloen
- Department of Human GeneticsRadboud University Medical CenterNijmegenthe Netherlands
| | - Tjitske Kleefstra
- Department of Human GeneticsRadboud University Medical CenterNijmegenthe Netherlands
| | - Rolph Pfundt
- Department of Human GeneticsRadboud University Medical CenterNijmegenthe Netherlands
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15
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Tadros S, Wang R, Waters JJ, Waterman C, Collins AL, Collinson MN, Ahn JW, Josifova D, Chetan R, Kumar A. Inherited 2q23.1 microdeletions involving the MBD5 locus. Mol Genet Genomic Med 2017; 5:608-613. [PMID: 28944244 PMCID: PMC5606852 DOI: 10.1002/mgg3.316] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2017] [Revised: 05/31/2017] [Accepted: 06/02/2017] [Indexed: 02/06/2023] Open
Abstract
Background Microdeletions of 2q23.1 disrupting MBD5 and loss of function mutations of MBD5 cause MBD5‐Associated Neurodevelopmental disorders (MAND). Nearly all reported patients have been isolated cases of de novo origin. Methods This study investigates three families with inherited MBD5 mutations from three different Regional Genetics Centres in the UK. Results Two of the parents in the study had MBD5 deletions in a mosaic form. The parent with an MBD5 deletion in an apparently nonmosaic form has a psychiatric disorder in the absence of developmental delay or dysmorphism. Conclusions Inherited forms of MBD5 deletions are rare, but do occur, especially in a mosaic form. The phenotypic spectrum of MAND may be wider than previously thought.
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Affiliation(s)
- Shereen Tadros
- North East Thames Regional Genetics ServiceGreat Ormond Street HospitalLondonWC1N 3JHUK
| | - Rubin Wang
- North East Thames Regional Genetics ServiceGreat Ormond Street HospitalLondonWC1N 3JHUK
| | - Jonathan J Waters
- North East Thames Regional Genetics ServiceGreat Ormond Street HospitalLondonWC1N 3JHUK
| | - Christine Waterman
- Wessex Regional Genetics LaboratorySalisbury NHS Foundation TrustOdstock RoadSalisburySP2 8BJUK
| | - Amanda L Collins
- Wessex Clinical Genetics ServicePrincess Anne HospitalMailpoint 627SouthamptonSO16 5YAUK
| | - Morag N Collinson
- Wessex Regional Genetics LaboratorySalisbury NHS Foundation TrustOdstock RoadSalisburySP2 8BJUK
| | - Joo W Ahn
- South East Thames Regional Genetics ServiceGuy's HospitalGreat Maze PondLondonSE1 9RTUK
| | - Dragana Josifova
- South East Thames Regional Genetics ServiceGuy's HospitalGreat Maze PondLondonSE1 9RTUK
| | - Ravi Chetan
- Department of PaediatricsSouthend University HospitalWestcliff on SeaSS0 0RYUK
| | - Ajith Kumar
- North East Thames Regional Genetics ServiceGreat Ormond Street HospitalLondonWC1N 3JHUK
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16
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Naj AC, Schellenberg GD. Genomic variants, genes, and pathways of Alzheimer's disease: An overview. Am J Med Genet B Neuropsychiatr Genet 2017; 174:5-26. [PMID: 27943641 PMCID: PMC6179157 DOI: 10.1002/ajmg.b.32499] [Citation(s) in RCA: 125] [Impact Index Per Article: 17.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/04/2016] [Accepted: 09/19/2016] [Indexed: 12/19/2022]
Abstract
Alzheimer's disease (AD) (MIM: 104300) is a highly heritable disease with great complexity in its genetic contributors, and represents the most common form of dementia. With the gradual aging of the world's population, leading to increased prevalence of AD, and the substantial cost of care for those afflicted, identifying the genetic causes of disease represents a critical effort in identifying therapeutic targets. Here we provide a comprehensive review of genomic studies of AD, from the earliest linkage studies identifying monogenic contributors to early-onset forms of AD to the genome-wide and rare variant association studies of recent years that are being used to characterize the mosaic of genetic contributors to late-onset AD (LOAD), and which have identified approximately ∼20 genes with common variants contributing to LOAD risk. In addition, we explore studies employing alternative approaches to identify genetic contributors to AD, including studies of AD-related phenotypes and multi-variant association studies such as pathway analyses. Finally, we introduce studies of next-generation sequencing, which have recently helped identify multiple low-frequency and rare variant contributors to AD, and discuss on-going efforts with next-generation sequencing studies to develop statistically well- powered and comprehensive genomic studies of AD. Through this review, we help uncover the many insights the genetics of AD have provided into the pathways and pathophysiology of AD. © 2016 Wiley Periodicals, Inc.
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Affiliation(s)
- Adam C Naj
- Department of Biostatistics and Epidemiology/Center for Clinical Epidemiology and Biostatistics, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania
| | - Gerard D Schellenberg
- Department of Pathology and Laboratory Medicine, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania
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17
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Whitton L, Cosgrove D, Clarkson C, Harold D, Kendall K, Richards A, Mantripragada K, Owen MJ, O'Donovan MC, Walters J, Hartmann A, Konte B, Rujescu D, Gill M, Corvin A, Rea S, Donohoe G, Morris DW. Cognitive analysis of schizophrenia risk genes that function as epigenetic regulators of gene expression. Am J Med Genet B Neuropsychiatr Genet 2016; 171:1170-1179. [PMID: 27762073 DOI: 10.1002/ajmg.b.32503] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/07/2016] [Accepted: 09/27/2016] [Indexed: 12/13/2022]
Abstract
Epigenetic mechanisms are an important heritable and dynamic means of regulating various genomic functions, including gene expression, to orchestrate brain development, adult neurogenesis, and synaptic plasticity. These processes when perturbed are thought to contribute to schizophrenia pathophysiology. A core feature of schizophrenia is cognitive dysfunction. For genetic disorders where cognitive impairment is more severe such as intellectual disability, there are a disproportionally high number of genes involved in the epigenetic regulation of gene transcription. Evidence now supports some shared genetic aetiology between schizophrenia and intellectual disability. GWAS have identified 108 chromosomal regions associated with schizophrenia risk that span 350 genes. This study identified genes mapping to those loci that have epigenetic functions, and tested the risk alleles defining those loci for association with cognitive deficits. We developed a list of 350 genes with epigenetic functions and cross-referenced this with the GWAS loci. This identified eight candidate genes: BCL11B, CHD7, EP300, EPC2, GATAD2A, KDM3B, RERE, SATB2. Using a dataset of Irish psychosis cases and controls (n = 1235), the schizophrenia risk SNPs at these loci were tested for effects on IQ, working memory, episodic memory, and attention. Strongest associations were for rs6984242 with both measures of IQ (P = 0.001) and episodic memory (P = 0.007). We link rs6984242 to CHD7 via a long range eQTL. These associations were not replicated in independent samples. Our study highlights that a number of genes mapping to risk loci for schizophrenia may function as epigenetic regulators of gene expression but further studies are required to establish a role for these genes in cognition. © 2016 Wiley Periodicals, Inc.
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Affiliation(s)
- Laura Whitton
- Cognitive Genetics and Cognitive Therapy Group, Neuroimaging, Cognition and Genomics (NICOG) Centre and NCBES Galway Neuroscience Centre, School of Psychology and Discipline of Biochemistry, National University of Ireland Galway, Galway, Ireland
| | - Donna Cosgrove
- Cognitive Genetics and Cognitive Therapy Group, Neuroimaging, Cognition and Genomics (NICOG) Centre and NCBES Galway Neuroscience Centre, School of Psychology and Discipline of Biochemistry, National University of Ireland Galway, Galway, Ireland
| | - Christopher Clarkson
- Centre for Chromosome Biology, Discipline of Biochemistry, National University of Ireland Galway, Galway, Ireland
| | - Denise Harold
- Neuropsychiatric Genetics Research Group, Institute of Molecular Medicine and Discipline of Psychiatry, Trinity College Dublin, Dublin, Ireland.,School of Biotechnology, Dublin City University, Dublin, Ireland
| | - Kimberley Kendall
- MRC Centre for Neuropsychiatric Genetics and Genomics, Cardiff University School of Medicine, Cardiff, United Kingdom
| | - Alex Richards
- MRC Centre for Neuropsychiatric Genetics and Genomics, Cardiff University School of Medicine, Cardiff, United Kingdom
| | - Kiran Mantripragada
- MRC Centre for Neuropsychiatric Genetics and Genomics, Cardiff University School of Medicine, Cardiff, United Kingdom
| | - Michael J Owen
- MRC Centre for Neuropsychiatric Genetics and Genomics, Cardiff University School of Medicine, Cardiff, United Kingdom
| | - Michael C O'Donovan
- MRC Centre for Neuropsychiatric Genetics and Genomics, Cardiff University School of Medicine, Cardiff, United Kingdom
| | - James Walters
- MRC Centre for Neuropsychiatric Genetics and Genomics, Cardiff University School of Medicine, Cardiff, United Kingdom
| | | | - Betina Konte
- Department of Psychiatry, University of Halle, Halle, Germany
| | - Dan Rujescu
- Department of Psychiatry, University of Halle, Halle, Germany
| | | | - Michael Gill
- Neuropsychiatric Genetics Research Group, Institute of Molecular Medicine and Discipline of Psychiatry, Trinity College Dublin, Dublin, Ireland
| | - Aiden Corvin
- Neuropsychiatric Genetics Research Group, Institute of Molecular Medicine and Discipline of Psychiatry, Trinity College Dublin, Dublin, Ireland
| | - Stephen Rea
- Centre for Chromosome Biology, Discipline of Biochemistry, National University of Ireland Galway, Galway, Ireland
| | - Gary Donohoe
- Cognitive Genetics and Cognitive Therapy Group, Neuroimaging, Cognition and Genomics (NICOG) Centre and NCBES Galway Neuroscience Centre, School of Psychology and Discipline of Biochemistry, National University of Ireland Galway, Galway, Ireland
| | - Derek W Morris
- Cognitive Genetics and Cognitive Therapy Group, Neuroimaging, Cognition and Genomics (NICOG) Centre and NCBES Galway Neuroscience Centre, School of Psychology and Discipline of Biochemistry, National University of Ireland Galway, Galway, Ireland
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18
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Clinical and Molecular Aspects of MBD5-Associated Neurodevelopmental Disorder (MAND). Eur J Hum Genet 2016; 24:1235-43. [PMID: 27222293 DOI: 10.1038/ejhg.2016.35] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2015] [Revised: 03/03/2016] [Accepted: 03/08/2016] [Indexed: 11/08/2022] Open
Abstract
MBD5-associated neurodevelopmental disorder (MAND) is an umbrella term that describes a group of disorders, 2q23.1 deletion syndrome, 2q23.1 duplication syndrome, and MBD5 variants, that affect the function of methyl-binding domain 5 (MBD5) and share a common set of neurodevelopmental, cognitive, and behavioral impairments. This review provides a comprehensive clinical and molecular synopsis of 2q23.1 deletion syndrome. Approaches to diagnosis, genetic counseling, and up-to-date management are summarized, followed by a discussion of the molecular and functional role of MBD5. Finally, we also include a brief summary of MBD5 variants that affect function of MBD5 and 2q23.1 duplication syndrome.
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19
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Bravo-Oro A, Lurie IW, Elizondo-Cárdenas G, Peña-Zepeda C, Salazar-Martínez A, Correa-González C, Castrillo JL, Avila S, Esmer C. A novel interstitial deletion of 2q22.3 q23.3 in a patient with dysmorphic features, epilepsy, aganglionosis, pure red cell aplasia, and skeletal malformations. Am J Med Genet A 2015; 167A:1865-71. [PMID: 25988649 DOI: 10.1002/ajmg.a.36806] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2013] [Accepted: 09/08/2014] [Indexed: 12/24/2022]
Abstract
Many chromosomal deletions encompassing the 2q23.1 region have been described ranging from small deletions of 38 kb up to >19 Mb. Most phenotypic features of the 2q23.1 deletion syndrome are due to a MBD5 gene loss independent of the size of the deletion. Here, we describe a male patient harboring a novel interstitial deletion encompassing the 2q22.3 q23.3 chromosomal region. Array-CGH revealed a 7.1 Mb deletion causing haploinsufficiency of several genes including MBD5, ACVR2, KIF5C, and EPC2. This patient presents with additional findings to those already described in individuals who have deletions of MBD5 including toes absence of halluces, pure red cell aplasia, and intestinal aganglionosis. Interestingly, in the deleted region there are previously identified regulatory sequences which are located upstream to ZEB2, which is associated with Hirschsprung disease (HSCR). Several genes have been associated with pure red cell aplasia, but to our knowledge, this is the first time that 2q deletion is associated with this phenotype. These additional findings should be added to the list of manifestations associated with 2q deletion, and provide support for the hypothesis that this individual has a true contiguous gene deletion syndrome.
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Affiliation(s)
- Antonio Bravo-Oro
- Hospital Central "Dr. Ignacio Morones Prieto", San Luis Potosí, Mexico
| | - Iosif W Lurie
- Chromosome Disorder Outreach, Boca Raton, Florida, USA
| | | | | | | | | | | | | | - Carmen Esmer
- Hospital Central "Dr. Ignacio Morones Prieto", San Luis Potosí, Mexico
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20
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Gigek CO, Chen ES, Ota VK, Maussion G, Peng H, Vaillancourt K, Diallo AB, Lopez JP, Crapper L, Vasuta C, Chen GG, Ernst C. A molecular model for neurodevelopmental disorders. Transl Psychiatry 2015; 5:e565. [PMID: 25966365 PMCID: PMC4471287 DOI: 10.1038/tp.2015.56] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/11/2015] [Accepted: 03/24/2015] [Indexed: 01/24/2023] Open
Abstract
Genes implicated in neurodevelopmental disorders (NDDs) important in cognition and behavior may have convergent function and several cellular pathways have been implicated, including protein translational control, chromatin modification, and synapse assembly and maintenance. Here, we test the convergent effects of methyl-CpG binding domain 5 (MBD5) and special AT-rich binding protein 2 (SATB2) reduced dosage in human neural stem cells (NSCs), two genes implicated in 2q23.1 and 2q33.1 deletion syndromes, respectively, to develop a generalized model for NDDs. We used short hairpin RNA stably incorporated into healthy neural stem cells to supress MBD5 and SATB2 expression, and massively parallel RNA sequencing, DNA methylation sequencing and microRNA arrays to test the hypothesis that a primary etiology of NDDs is the disruption of the balance of NSC proliferation and differentiation. We show that reduced dosage of either gene leads to significant overlap of gene-expression patterns, microRNA patterns and DNA methylation states with control NSCs in a differentiating state, suggesting that a unifying feature of 2q23.1 and 2q33.1 deletion syndrome may be a lack of regulation between proliferation and differentiation in NSCs, as we observed previously for TCF4 and EHMT1 suppression following a similar experimental paradigm. We propose a model of NDDs whereby the balance of NSC proliferation and differentiation is affected, but where the molecules that drive this effect are largely specific to disease-causing genetic variation. NDDs are diverse, complex and unique, but the optimal balance of factors that determine when and where neural stem cells differentiate may be a major feature underlying the diverse phenotypic spectrum of NDDs.
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Affiliation(s)
- C O Gigek
- Department of Psychiatry, McGill Group for Suicide Studies, McGill University, Montreal, QC, Canada
| | - E S Chen
- Department of Psychiatry, McGill Group for Suicide Studies, McGill University, Montreal, QC, Canada
| | - V K Ota
- Department of Psychiatry, McGill Group for Suicide Studies, McGill University, Montreal, QC, Canada
| | - G Maussion
- Department of Psychiatry, McGill Group for Suicide Studies, McGill University, Montreal, QC, Canada
| | - H Peng
- Department of Psychiatry, McGill Group for Suicide Studies, McGill University, Montreal, QC, Canada
| | - K Vaillancourt
- Department of Psychiatry, McGill Group for Suicide Studies, McGill University, Montreal, QC, Canada
| | - A B Diallo
- Department of Psychiatry, McGill Group for Suicide Studies, McGill University, Montreal, QC, Canada
| | - J P Lopez
- Department of Psychiatry, McGill Group for Suicide Studies, McGill University, Montreal, QC, Canada
| | - L Crapper
- Department of Psychiatry, McGill Group for Suicide Studies, McGill University, Montreal, QC, Canada
| | - C Vasuta
- Department of Psychiatry, McGill Group for Suicide Studies, McGill University, Montreal, QC, Canada
| | - G G Chen
- Department of Psychiatry, McGill Group for Suicide Studies, McGill University, Montreal, QC, Canada
| | - C Ernst
- Department of Psychiatry, McGill Group for Suicide Studies, McGill University, Montreal, QC, Canada,Douglas Hospital Research Institute, 6875 LaSalle Boulevard, Frank Common Building Room 2101.2 Verdun, QC, Canada H4H 1R3. E-mail:
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21
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Phenotypic and molecular convergence of 2q23.1 deletion syndrome with other neurodevelopmental syndromes associated with autism spectrum disorder. Int J Mol Sci 2015; 16:7627-43. [PMID: 25853262 PMCID: PMC4425039 DOI: 10.3390/ijms16047627] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2015] [Revised: 03/19/2015] [Accepted: 03/19/2015] [Indexed: 12/21/2022] Open
Abstract
Roughly 20% of autism spectrum disorders (ASD) are syndromic with a well-established genetic cause. Studying the genes involved can provide insight into the molecular and cellular mechanisms of ASD. 2q23.1 deletion syndrome (causative gene, MBD5) is a recently identified genetic neurodevelopmental disorder associated with ASD. Mutations in MBD5 have been found in ASD cohorts. In this study, we provide a phenotypic update on the prevalent features of 2q23.1 deletion syndrome, which include severe intellectual disability, seizures, significant speech impairment, sleep disturbance, and autistic-like behavioral problems. Next, we examined the phenotypic, molecular, and network/pathway relationships between nine neurodevelopmental disorders associated with ASD: 2q23.1 deletion Rett, Angelman, Pitt-Hopkins, 2q23.1 duplication, 5q14.3 deletion, Kleefstra, Kabuki make-up, and Smith-Magenis syndromes. We show phenotypic overlaps consisting of intellectual disability, speech delay, seizures, sleep disturbance, hypotonia, and autistic-like behaviors. Molecularly, MBD5 possibly regulates the expression of UBE3A, TCF4, MEF2C, EHMT1 and RAI1. Network analysis reveals that there could be indirect protein interactions, further implicating function for these genes in common pathways. Further, we show that when MBD5 and RAI1 are haploinsufficient, they perturb several common pathways that are linked to neuronal and behavioral development. These findings support further investigations into the molecular and pathway relationships among genes linked to neurodevelopmental disorders and ASD, which will hopefully lead to common points of regulation that may be targeted toward therapeutic intervention.
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22
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Camarena V, Cao L, Abad C, Abrams A, Toledo Y, Araki K, Araki M, Walz K, Young JI. Disruption of Mbd5 in mice causes neuronal functional deficits and neurobehavioral abnormalities consistent with 2q23.1 microdeletion syndrome. EMBO Mol Med 2015; 6:1003-15. [PMID: 25001218 PMCID: PMC4154129 DOI: 10.15252/emmm.201404044] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
2q23.1 microdeletion syndrome is characterized by intellectual disability, motor delay, autistic-like behaviors, and a distinctive craniofacial phenotype. All patients carry a partial or total deletion of methyl-CpG-binding domain protein 5 (MBD5), suggesting that haploinsufficiency of this gene is responsible for the phenotype. To confirm this hypothesis and to examine the role of MBD5 in vivo, we have generated and characterized an Mbd5 gene-trap mouse model. Our study indicates that the Mbd5+/GT mouse model recapitulates most of the hallmark phenotypes observed in 2q23.1 deletion carriers including abnormal social behavior, cognitive impairment, and motor and craniofacial abnormalities. In addition, neuronal cultures uncovered a deficiency in neurite outgrowth. These findings support a causal role of MBD5 in 2q23.1 microdeletion syndrome and suggest a role for MBD5 in neuronal processes. The Mbd5+/GT mouse model will advance our understanding of the abnormal brain development underlying the emergence of 2q23.1 deletion-associated behavioral and cognitive symptoms. Subject Categories Genetics, Gene Therapy & Genetic Disease; Neuroscience
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Affiliation(s)
- Vladimir Camarena
- Dr. John T. Macdonald Foundation Department of Human Genetics, University of Miami, Miami, FL, USA
| | - Lei Cao
- Dr. John T. Macdonald Foundation Department of Human Genetics, University of Miami, Miami, FL, USA
| | - Clemer Abad
- John P. Hussman Institute for Human Genomics, Miller School of Medicine University of Miami, Miami, FL, USA
| | - Alexander Abrams
- Dr. John T. Macdonald Foundation Department of Human Genetics, University of Miami, Miami, FL, USA
| | - Yaima Toledo
- Dr. John T. Macdonald Foundation Department of Human Genetics, University of Miami, Miami, FL, USA
| | - Kimi Araki
- Institute of Resource Development and Analysis, Kumamoto University, Kumamoto, Japan
| | - Masatake Araki
- Institute of Resource Development and Analysis, Kumamoto University, Kumamoto, Japan
| | - Katherina Walz
- Dr. John T. Macdonald Foundation Department of Human Genetics, University of Miami, Miami, FL, USA John P. Hussman Institute for Human Genomics, Miller School of Medicine University of Miami, Miami, FL, USA
| | - Juan I Young
- Dr. John T. Macdonald Foundation Department of Human Genetics, University of Miami, Miami, FL, USA John P. Hussman Institute for Human Genomics, Miller School of Medicine University of Miami, Miami, FL, USA
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Tan WH, Bird LM, Thibert RL, Williams CA. If not Angelman, what is it? A review of Angelman-like syndromes. Am J Med Genet A 2014; 164A:975-92. [PMID: 24779060 DOI: 10.1002/ajmg.a.36416] [Citation(s) in RCA: 67] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Angelman syndrome (AS) is caused by a lack of expression of the maternally inherited UBE3A gene in the brain. However, about 10% of individuals with a clinical diagnosis of AS do not have an identifiable molecular defect. It is likely that most of those individuals have an AS-like syndrome that is clinically and molecularly distinct from AS. These AS-like syndromes can be broadly classified into chromosomal microdeletion and microduplication syndromes, and single-gene disorders. The microdeletion/microduplication syndromes are now easily identified by chromosomal microarray analysis and include Phelan–McDermid syndrome (chromosome 22q13.3 deletion), MBD5 haploinsufficiency syndrome (chromosome 2q23.1 deletion), and KANSL1 haploinsufficiency syndrome (chromosome 17q21.31 deletion). The single-gene disorders include Pitt–Hopkins syndrome (TCF4), Christianson syndrome (SLC9A6), Mowat–Wilson syndrome (ZEB2), Kleefstra syndrome (EHMT1), and Rett (MECP2) syndrome. They also include disorders due to mutations in HERC2, adenylosuccinase lyase (ADSL), CDKL5, FOXG1, MECP2 (duplications), MEF2C, and ATRX. Although many of these single-gene disorders can be caused by chromosomal microdeletions resulting in haploinsufficiency of the critical gene, the individual disorders are often caused by intragenic mutations that cannot be detected by chromosomal microarray analysis. We provide an overview of the clinical features of these syndromes, comparing and contrasting them with AS, in the hope that it will help guide clinicians in the diagnostic work-up of individuals with AS-like syndromes.
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Mullegama SV, Pugliesi L, Burns B, Shah Z, Tahir R, Gu Y, Nelson DL, Elsea SH. MBD5 haploinsufficiency is associated with sleep disturbance and disrupts circadian pathways common to Smith-Magenis and fragile X syndromes. Eur J Hum Genet 2014; 23:781-9. [PMID: 25271084 DOI: 10.1038/ejhg.2014.200] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2014] [Revised: 07/23/2014] [Accepted: 08/26/2014] [Indexed: 11/09/2022] Open
Abstract
Individuals with autism spectrum disorders (ASD) who have an identifiable single-gene neurodevelopmental disorder (NDD), such as fragile X syndrome (FXS, FMR1), Smith-Magenis syndrome (SMS, RAI1), or 2q23.1 deletion syndrome (del 2q23.1, MBD5) share phenotypic features, including a high prevalence of sleep disturbance. We describe the circadian deficits in del 2q23.1 through caregiver surveys in which we identify several frequent sleep anomalies, including night/early awakenings, coughing/snoring loudly, and difficulty falling asleep. We couple these findings with studies on the molecular analysis of the circadian deficits associated with haploinsufficiency of MBD5 in which circadian gene mRNA levels of NR1D2, PER1, PER2, and PER3 were altered in del 2q23.1 lymphoblastoid cell lines (LCLs), signifying that haploinsufficiency of MBD5 can result in dysregulation of circadian rhythm gene expression. These findings were further supported by expression microarrays of MBD5 siRNA knockdown cells that showed significantly altered expression of additional circadian rhythm signaling pathway genes. Based on the common sleep phenotypes observed in del 2q23.1, SMS, and FXS patients, we explored the possibility that MBD5, RAI1, and FMR1 function in overlapping circadian rhythm pathways. Bioinformatic analysis identified conserved putative E boxes in MBD5 and RAI1, and expression levels of NR1D2 and CRY2 were significantly reduced in patient LCLs. Circadian and mTOR signaling pathways, both associated with sleep disturbance, were altered in both MBD5 and RAI1 knockdown microarray data, overlapping with findings associated with FMR1. These data support phenotypic and molecular overlaps across these syndromes that may be exploited to provide therapeutic intervention for multiple disorders.
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Affiliation(s)
- Sureni V Mullegama
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, USA
| | - Loren Pugliesi
- Department of Human and Molecular Genetics, Virginia Commonwealth University School of Medicine, Richmond, VA, USA
| | - Brooke Burns
- Department of Human and Molecular Genetics, Virginia Commonwealth University School of Medicine, Richmond, VA, USA
| | - Zalak Shah
- Department of Human and Molecular Genetics, Virginia Commonwealth University School of Medicine, Richmond, VA, USA
| | - Raiha Tahir
- Department of Human and Molecular Genetics, Virginia Commonwealth University School of Medicine, Richmond, VA, USA
| | - Yanghong Gu
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, USA
| | - David L Nelson
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, USA
| | - Sarah H Elsea
- 1] Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, USA [2] Department of Human and Molecular Genetics, Virginia Commonwealth University School of Medicine, Richmond, VA, USA
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25
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Greally MT, Robinson E, Allen NM, O'Donovan D, Crolla JA. De novo interstitial deletion 2q14.1q22.1: is there a recognizable phenotype? Am J Med Genet A 2014; 164A:3194-202. [PMID: 25263257 DOI: 10.1002/ajmg.a.36786] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2013] [Accepted: 08/21/2014] [Indexed: 12/29/2022]
Abstract
In this report we describe a male patient with a rare de novo interstitial deletion of chromosome 2q14.1-q22.1. His karyotype was reported as 46,XY,del(2)(q13q21) but subsequent array comparative genomic hybridization (array CGH) analysis redefined the deletion breakpoints as 2q14.1 and 2q22.1. Eight patients have been reported with deletions either within or spanning the region 2q13 or 2q14 to 2q22.1. In five patients the diagnosis was made by karyotype analysis alone and in three reported patients and the proband array CGH analysis was also performed. When the proband was compared with the eight previously reported patients it was apparent that they shared many clinical findings suggesting that patients with a de novo interstitial deletion involving 2q13 or 2q14 to 2q21 or 2q22 may have a recognizable phenotype. There are 14 known disease-associated genes in the deleted region of 2q14.1-q22.1 and their possible phenotypic effects on the proband and the eight previously reported patients are discussed.
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Affiliation(s)
- Marie T Greally
- National Centre for Medical Genetics, Our Lady's Children's Hospital, Crumlin, Dublin, Ireland
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26
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Abstract
Despite genetic evidence implicating MBD5 as the only overlapping gene between various 2q23.1 microdeletions, the function of MBD5 and its causality to 2q23.1 microdeletion syndrome, a disorder characterized by developmental delay and autistic features, has yet to be determined. In this issue of EMBO Molecular Medicine, Camarena et al generate an Mbd5 gene-trap mouse model and show for the first time that mice with reduced MBD5 expression develop behavioral abnormalities with neuronal function deficits, mimicking symptoms in 2q23.1 microdeletion syndrome, thus supporting a causal role for MBD5 haploinsufficiency in the disorder.
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Affiliation(s)
- Deborah Y Kwon
- Department of Genetics, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, USA
| | - Zhaolan Zhou
- Department of Genetics, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, USA
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Du X, An Y, Yu L, Liu R, Qin Y, Guo X, Sun D, Zhou S, Wu B, Jiang YH, Wang Y. A genomic copy number variant analysis implicates the MBD5 and HNRNPU genes in Chinese children with infantile spasms and expands the clinical spectrum of 2q23.1 deletion. BMC MEDICAL GENETICS 2014; 15:62. [PMID: 24885232 PMCID: PMC4061518 DOI: 10.1186/1471-2350-15-62] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/10/2014] [Accepted: 05/13/2014] [Indexed: 02/06/2023]
Abstract
Background Infantile spasms (IS) is a specific type of epileptic encephalopathy associated with severe developmental disabilities. Genetic factors are strongly implicated in IS, however, the exact genetic defects remain unknown in the majority of cases. Rare mutations in a single gene or in copy number variants (CNVs) have been implicated in IS of children in Western countries. The objective of this study was to dissect the role of copy number variations in Chinese children with infantile spasms. Methods We used the Agilent Human Genome CGH microarray 180 K for genome-wide detection of CNVs. Real-time qPCR was used to validate the CNVs. We performed genomic and medical annotations for individual CNVs to determine the pathogenicity of CNVs related to IS. Results We report herein the first genome-wide CNV analysis in children with IS, detecting a total of 14 CNVs in a cohort of 47 Chinese children with IS. Four CNVs (4/47 = 8.5%) (1q21.1 gain; 1q44, 2q31.1, and 17p13 loss) are considered to be pathogenic. The CNV loss at 17p13.3 contains PAFAH1B1 (LIS1), a causative gene for lissencephaly. Although the CNVs at 1q21.1, 1q44, and 2q23.1 have been previously implicated in a wide spectrum of clinical features including autism spectrum disorders (ASD) and generalized seizure, our study is the first report identifying them in individuals with a primary diagnosis of IS. The CNV loss in the 1q44 region contains HNRNPU, a strong candidate gene recently suggested in IS by the whole exome sequencing of children with IS. The CNV loss at 2q23.1 includes MBD5, a methyl-DNA binding protein that is a causative gene of ASD and a candidate gene for epileptic encephalopathy. We also report a distinct clinical presentation of IS, microcephaly, intellectual disability, and absent hallux in a case with the 2q23.1 deletion. Conclusion Our findings strongly support the role of CNVs in infantile spasms and expand the clinical spectrum associate with 2q23.1 deletion. In particular, our study implicates the HNRNPU and MBD5 genes in Chinese children with IS. Our study also supports that the molecular mechanisms of infantile spasms appear conserved among different ethnic backgrounds.
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Affiliation(s)
| | | | | | | | | | | | | | | | | | - Yong-Hui Jiang
- Division of Neurology, Children's Hospital of Fudan University, 399 Wan Yuan Road, Shanghai 201102, China.
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28
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Prioritization of neurodevelopmental disease genes by discovery of new mutations. Nat Neurosci 2014; 17:764-72. [PMID: 24866042 DOI: 10.1038/nn.3703] [Citation(s) in RCA: 119] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2014] [Accepted: 03/26/2014] [Indexed: 12/14/2022]
Abstract
Advances in genome sequencing technologies have begun to revolutionize neurogenetics, allowing the full spectrum of genetic variation to be better understood in relation to disease. Exome sequencing of hundreds to thousands of samples from patients with autism spectrum disorder, intellectual disability, epilepsy and schizophrenia provides strong evidence of the importance of de novo and gene-disruptive events. There are now several hundred new candidate genes and targeted resequencing technologies that allow screening of dozens of genes in tens of thousands of individuals with high specificity and sensitivity. The decision of which genes to pursue depends on many factors, including recurrence, previous evidence of overlap with pathogenic copy number variants, the position of the mutation in the protein, the mutational burden among healthy individuals and membership of the candidate gene in disease-implicated protein networks. We discuss these emerging criteria for gene prioritization and the potential impact on the field of neuroscience.
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29
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Willemsen MH, Ba W, Wissink-Lindhout WM, de Brouwer APM, Haas SA, Bienek M, Hu H, Vissers LELM, van Bokhoven H, Kalscheuer V, Nadif Kasri N, Kleefstra T. Involvement of the kinesin family members KIF4A and KIF5C in intellectual disability and synaptic function. J Med Genet 2014; 51:487-94. [PMID: 24812067 DOI: 10.1136/jmedgenet-2013-102182] [Citation(s) in RCA: 68] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
INTRODUCTION Kinesin superfamily (KIF) genes encode motor proteins that have fundamental roles in brain functioning, development, survival and plasticity by regulating the transport of cargo along microtubules within axons, dendrites and synapses. Mouse knockout studies support these important functions in the nervous system. The role of KIF genes in intellectual disability (ID) has so far received limited attention, although previous studies have suggested that many ID genes impinge on synaptic function. METHODS By applying next-generation sequencing (NGS) in ID patients, we identified likely pathogenic mutations in KIF4A and KIF5C. To further confirm the pathogenicity of these mutations, we performed functional studies at the level of synaptic function in primary rat hippocampal neurons. RESULTS AND CONCLUSIONS Four males from a single family with a disruptive mutation in the X-linked KIF4A (c.1489-8_1490delins10; p.?- exon skipping) showed mild to moderate ID and epilepsy. A female patient with a de novo missense mutation in KIF5C (c.11465A>C; p.(Glu237Lys)) presented with severe ID, epilepsy, microcephaly and cortical malformation. Knock-down of Kif4a in rat primary hippocampal neurons altered the balance between excitatory and inhibitory synaptic transmission, whereas the mutation in Kif5c affected its protein function at excitatory synapses. Our results suggest that mutations in KIF4A and KIF5C cause ID by tipping the balance between excitatory and inhibitory synaptic excitability.
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Affiliation(s)
- Marjolein H Willemsen
- Department of Human Genetics, Radboud university medical center, Nijmegen, The Netherlands Nijmegen Centre for Molecular Life Sciences, Institute for Genetic and Metabolic Diseases, Radboud university medical center, Nijmegen, The Netherlands
| | - Wei Ba
- Department of Human Genetics, Radboud university medical center, Nijmegen, The Netherlands Department of Cognitive Neuroscience, Radboud university medical center, Nijmegen, The Netherlands Donders Institute for Brain, Cognition and Behaviour, Radboud university medical center, Nijmegen, The Netherlands
| | | | - Arjan P M de Brouwer
- Department of Human Genetics, Radboud university medical center, Nijmegen, The Netherlands Nijmegen Centre for Molecular Life Sciences, Institute for Genetic and Metabolic Diseases, Radboud university medical center, Nijmegen, The Netherlands
| | - Stefan A Haas
- Department of Computational Molecular Biology, Max Planck Institute for Molecular Genetics, Berlin, Germany
| | - Melanie Bienek
- Department of Human Molecular Genetics, Max Planck Institute for Molecular Genetics, Berlin, Germany
| | - Hao Hu
- Department of Human Molecular Genetics, Max Planck Institute for Molecular Genetics, Berlin, Germany
| | - Lisenka E L M Vissers
- Department of Human Genetics, Radboud university medical center, Nijmegen, The Netherlands Nijmegen Centre for Molecular Life Sciences, Institute for Genetic and Metabolic Diseases, Radboud university medical center, Nijmegen, The Netherlands
| | - Hans van Bokhoven
- Department of Human Genetics, Radboud university medical center, Nijmegen, The Netherlands Nijmegen Centre for Molecular Life Sciences, Institute for Genetic and Metabolic Diseases, Radboud university medical center, Nijmegen, The Netherlands Department of Cognitive Neuroscience, Radboud university medical center, Nijmegen, The Netherlands Donders Institute for Brain, Cognition and Behaviour, Radboud university medical center, Nijmegen, The Netherlands
| | - Vera Kalscheuer
- Department of Human Molecular Genetics, Max Planck Institute for Molecular Genetics, Berlin, Germany
| | - Nael Nadif Kasri
- Department of Human Genetics, Radboud university medical center, Nijmegen, The Netherlands Nijmegen Centre for Molecular Life Sciences, Institute for Genetic and Metabolic Diseases, Radboud university medical center, Nijmegen, The Netherlands Department of Cognitive Neuroscience, Radboud university medical center, Nijmegen, The Netherlands Donders Institute for Brain, Cognition and Behaviour, Radboud university medical center, Nijmegen, The Netherlands
| | - Tjitske Kleefstra
- Department of Human Genetics, Radboud university medical center, Nijmegen, The Netherlands Nijmegen Centre for Molecular Life Sciences, Institute for Genetic and Metabolic Diseases, Radboud university medical center, Nijmegen, The Netherlands
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Suliman R, Ben-David E, Shifman S. Chromatin regulators, phenotypic robustness, and autism risk. Front Genet 2014; 5:81. [PMID: 24782891 PMCID: PMC3989700 DOI: 10.3389/fgene.2014.00081] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2013] [Accepted: 03/25/2014] [Indexed: 12/14/2022] Open
Abstract
Though extensively characterized clinically, the causes of autism spectrum disorder (ASD) remain a mystery. ASD is known to have a strong genetic basis, but it is genetically very heterogeneous. Recent studies have estimated that de novo disruptive mutations in hundreds of genes may contribute to ASD. However, it is unclear how it is possible for mutations in so many different genes to contribute to ASD. Recent findings suggest that many of the mutations disrupt genes involved in transcription regulation that are expressed prenatally in the developing brain. De novo disruptive mutations are also more frequent in girls with ASD, despite the fact that ASD is more prevalent in boys. In this paper, we hypothesize that loss of robustness may contribute to ASD. Loss of phenotypic robustness may be caused by mutations that disrupt capacitors that operate in the developing brain. This may lead to the release of cryptic genetic variation that contributes to ASD. Reduced robustness is consistent with the observed variability in expressivity and incomplete penetrance. It is also consistent with the hypothesis that the development of the female brain is more robust, and it may explain the higher rate and severity of disruptive de novo mutations in girls with ASD.
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Affiliation(s)
- Reut Suliman
- Department of Genetics, The Institute of Life Sciences, The Hebrew University of Jerusalem Jerusalem, Israel
| | - Eyal Ben-David
- Department of Genetics, The Institute of Life Sciences, The Hebrew University of Jerusalem Jerusalem, Israel
| | - Sagiv Shifman
- Department of Genetics, The Institute of Life Sciences, The Hebrew University of Jerusalem Jerusalem, Israel
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31
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Lo-Castro A, Curatolo P. Epilepsy associated with autism and attention deficit hyperactivity disorder: is there a genetic link? Brain Dev 2014; 36:185-93. [PMID: 23726375 DOI: 10.1016/j.braindev.2013.04.013] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/13/2013] [Revised: 04/28/2013] [Accepted: 04/30/2013] [Indexed: 12/26/2022]
Abstract
Autism Spectrum Disorders (ASDs) and Attention Deficit and Hyperactivity Disorder (ADHD) are the most common comorbid conditions associated with childhood epilepsy. The co-occurrence of an epilepsy/autism phenotype or an epilepsy/ADHD phenotype has a complex and heterogeneous pathogenesis, resulting from several altered neurobiological mechanisms involved in early brain development, and influencing synaptic plasticity, neurotransmission and functional connectivity. Rare clinically relevant chromosomal aberrations, in addition to environmental factors, may confer an increased risk for ASDs/ADHD comorbid with epilepsy. The majority of the candidate genes are involved in synaptic formation/remodeling/maintenance (NRX1, CNTN4, DCLK2, CNTNAP2, TRIM32, ASTN2, CTNTN5, SYN1), neurotransmission (SYNGAP1, GABRG1, CHRNA7), or DNA methylation/chromatin remodeling (MBD5). Two genetic disorders, such as Tuberous sclerosis and Fragile X syndrome may serve as models for understanding the common pathogenic pathways leading to ASDs and ADHD comorbidities in children with epilepsy, offering the potential for new biologically focused treatment options.
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Affiliation(s)
- Adriana Lo-Castro
- Neuroscience Department, Pediatric Neurology and Psychiatry Unit, Tor Vergata University of Rome, Italy.
| | - Paolo Curatolo
- Neuroscience Department, Pediatric Neurology and Psychiatry Unit, Tor Vergata University of Rome, Italy
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32
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Hodge JC, Mitchell E, Pillalamarri V, Toler TL, Bartel F, Kearney HM, Zou YS, Tan WH, Hanscom C, Kirmani S, Hanson RR, Skinner SA, Rogers C, Everman DB, Boyd E, Mullegama SV, Keelean-Fuller D, Powell CM, Elsea SH, Morton CC, Gusella JF, DuPont B, Chaubey A, Lin AE, Talkowski ME, Talkowski ME. Disruption of MBD5 contributes to a spectrum of psychopathology and neurodevelopmental abnormalities. Mol Psychiatry 2014; 19:368-79. [PMID: 23587880 PMCID: PMC4756476 DOI: 10.1038/mp.2013.42] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/22/2012] [Revised: 02/11/2013] [Accepted: 03/06/2013] [Indexed: 01/11/2023]
Abstract
Microdeletions of chromosomal region 2q23.1 that disrupt MBD5 (methyl-CpG-binding domain protein 5) contribute to a spectrum of neurodevelopmental phenotypes; however, the impact of this locus on human psychopathology has not been fully explored. To characterize the structural variation landscape of MBD5 disruptions and the associated human psychopathology, 22 individuals with genomic disruption of MBD5 (translocation, point mutation and deletion) were identified through whole-genome sequencing or cytogenomic microarray at 11 molecular diagnostic centers. The genomic impact ranged from a single base pair to 5.4 Mb. Parents were available for 11 cases, all of which confirmed that the rearrangement arose de novo. Phenotypes were largely indistinguishable between patients with full-segment 2q23.1 deletions and those with intragenic MBD5 rearrangements, including alterations confined entirely to the 5'-untranslated region, confirming the critical impact of non-coding sequence at this locus. We identified heterogeneous, multisystem pathogenic effects of MBD5 disruption and characterized the associated spectrum of psychopathology, including the novel finding of anxiety and bipolar disorder in multiple patients. Importantly, one of the unique features of the oldest known patient was behavioral regression. Analyses also revealed phenotypes that distinguish MBD5 disruptions from seven well-established syndromes with significant diagnostic overlap. This study demonstrates that haploinsufficiency of MBD5 causes diverse phenotypes, yields insight into the spectrum of resulting neurodevelopmental and behavioral psychopathology and provides clinical context for interpretation of MBD5 structural variations. Empirical evidence also indicates that disruption of non-coding MBD5 regulatory regions is sufficient for clinical manifestation, highlighting the limitations of exon-focused assessments. These results suggest an ongoing perturbation of neurological function throughout the lifespan, including risks for neurobehavioral regression.
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Affiliation(s)
- Jennelle C. Hodge
- Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, MN, USA,Department of Medical Genetics, Mayo Clinic, Rochester, 55905, USA
| | - Elyse Mitchell
- Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, MN, USA
| | - Vamsee Pillalamarri
- Center for Human Genetic Research, Massachusetts General Hospital, Boston, MA, USA
| | - Tomi L. Toler
- Medical Genetics, MassGeneral Hospital for Children, Boston, MA, USA
| | | | | | - Ying S. Zou
- Clinical Cytogenetics Laboratory, Pathology Associates Medical Laboratories, Spokane, WA, USA
| | - Wen-Hann Tan
- Division of Genetics, Boston Children’s Hospital, Boston, MA, USA,Harvard Medical School, Boston, MA, USA
| | - Carrie Hanscom
- Center for Human Genetic Research, Massachusetts General Hospital, Boston, MA, USA
| | - Salman Kirmani
- Department of Medical Genetics, Mayo Clinic, Rochester, 55905, USA
| | - Rae R. Hanson
- Child Neurology, Department of Neurosciences, Mayo Clinic Health System, Eau Claire, WI, USA
| | | | | | | | - Ellen Boyd
- Fullerton Genetic Center, Mission Health, Asheville, NC, USA
| | - Sureni V. Mullegama
- Department of Human and Molecular Genetics, Virginia Commonwealth University School of Medicine, Richmond, VA, USA
| | - Debra Keelean-Fuller
- Department of Pediatrics and Genetics, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Cynthia M. Powell
- Department of Pediatrics and Genetics, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Sarah H. Elsea
- Department of Human and Molecular Genetics, Virginia Commonwealth University School of Medicine, Richmond, VA, USA,Department of Pediatrics, Virginia Commonwealth University School of Medicine, Richmond, VA, USA
| | - Cynthia C. Morton
- Harvard Medical School, Boston, MA, USA,Departments of Obstetrics, Gynecology and Reproductive Biology and of Pathology, Brigham and Women’s Hospital, Boston, MA, USA,Program in Medical and Population Genetics, Broad Institute of Harvard and M.I.T., Cambridge, MA, USA
| | - James F. Gusella
- Center for Human Genetic Research, Massachusetts General Hospital, Boston, MA, USA,Program in Medical and Population Genetics, Broad Institute of Harvard and M.I.T., Cambridge, MA, USA,Departments of Genetics and Neurology, Harvard Medical School, Cambridge, MA, USA
| | | | | | - Angela E. Lin
- Center for Human Genetic Research, Massachusetts General Hospital, Boston, MA, USA,Medical Genetics, MassGeneral Hospital for Children, Boston, MA, USA
| | - Michael E. Talkowski
- Center for Human Genetic Research, Massachusetts General Hospital, Boston, MA, USA,Program in Medical and Population Genetics, Broad Institute of Harvard and M.I.T., Cambridge, MA, USA,Departments of Genetics and Neurology, Harvard Medical School, Cambridge, MA, USA
| | - M E Talkowski
- 1] Center for Human Genetic Research, Massachusetts General Hospital, Boston, MA, USA [2] Program in Medical and Population Genetics, Broad Institute of Harvard and MIT, Cambridge, MA, USA [3] Departments of Genetics and Neurology, Harvard Medical School, Cambridge, MA, USA
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Walz K, Young JI. The methyl binding domain containing protein MBD5 is a transcriptional regulator responsible for 2q23.1 deletion syndrome. Rare Dis 2014; 2:e967151. [PMID: 26942102 PMCID: PMC4755234 DOI: 10.4161/2167549x.2014.967151] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2014] [Revised: 09/03/2014] [Accepted: 09/11/2014] [Indexed: 01/03/2023] Open
Abstract
2Iq23.1 microdeletion syndrome is a recently described rare disease that includes intellectual disability, motor delay, autistic-like behaviors, and craniofacial abnormalities. Dosage insufficiency of the methyl-CpG-binding domain protein 5 (MBD5) gene was suggested as the genetic cause, since all the described patients carry a partial or total heterozygous deletion of MBD5. We reported the generation and characterization of a mouse model with haploinsufficiency for Mbd5 that confirmed this hypothesis. As in human 2q23.1 microdeletion syndrome, the MBD5 (+/GT) mouse model exhibited abnormal social behavior, cognitive impairment, and motor and craniofacial abnormalities, supporting a causal role for MBD5 in 2q23.1 microdeletion syndrome. The use of mouse neuronal cultures uncovered a deficiency in neurite outgrowth, suggesting the participation of MBD5 in neuronal processes. The study of the MBD5 (+/GT) mouse advanced our understanding of the abnormal brain development associated with behavioral and cognitive symptoms.
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Affiliation(s)
- Katherina Walz
- Dr. John T Macdonald Foundation; Department of Human Genetics; University of Miami; FL, USA; John P. Hussman Institute for Human Genomics; University of Miami; FL, USA; Department of Medicine; Miller School of Medicine; University of Miami; FL, USA
| | - Juan I Young
- Dr. John T Macdonald Foundation; Department of Human Genetics; University of Miami; FL, USA; John P. Hussman Institute for Human Genomics; University of Miami; FL, USA
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Diagnosis of copy number variation by Illumina next generation sequencing is comparable in performance to oligonucleotide array comparative genomic hybridisation. Genomics 2013; 102:174-81. [DOI: 10.1016/j.ygeno.2013.04.006] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2012] [Revised: 04/04/2013] [Accepted: 04/09/2013] [Indexed: 11/20/2022]
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Genetic insights into the functional elements of language. Hum Genet 2013; 132:959-86. [PMID: 23749164 DOI: 10.1007/s00439-013-1317-0] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2012] [Accepted: 05/22/2013] [Indexed: 12/11/2022]
Abstract
Language disorders cover a wide range of conditions with heterologous and overlapping phenotypes and complex etiologies harboring both genetic and environmental influences. Genetic approaches including the identification of genes linked to speech and language phenotypes and the characterization of normal and aberrant functions of these genes have, in recent years, unraveled complex details of molecular and cognitive mechanisms and provided valuable insight into the biological foundations of language. Consistent with this approach, we have reviewed the functional aspects of allelic variants of genes which are currently known to be either causally associated with disorders of speech and language or impact upon the spectrum of normal language ability. We have also reviewed candidate genes associated with heritable speech and language disorders. In addition, we have evaluated language phenotypes and associated genetic components in developmental syndromes that, together with a spectrum of altered language abilities, manifest various phenotypes and offer details of multifactorial determinants of language function. Data from this review have revealed a predominance of regulatory networks involved in the control of differentiation and functioning of neurons, neuronal tracks and connections among brain structures associated with both cognitive and language faculties. Our findings, furthermore, have highlighted several multifactorial determinants in overlapping speech and language phenotypes. Collectively this analysis has revealed an interconnected developmental network and a close association of the language faculty with cognitive functions, a finding that has the potential to provide insight into linguistic hypotheses defining in particular, the contribution of genetic elements to and the modular nature of the language faculty.
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Shichiji M, Ito Y, Shimojima K, Nakamu H, Oguni H, Osawa M, Yamamoto T. A cryptic microdeletion including MBD5 occurring within the breakpoint of a reciprocal translocation between chromosomes 2 and 5 in a patient with developmental delay and obesity. Am J Med Genet A 2013; 161A:850-5. [PMID: 23494922 DOI: 10.1002/ajmg.a.35768] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2011] [Accepted: 10/13/2012] [Indexed: 12/17/2022]
Abstract
The 2q23.1 deletion syndrome has been recently recognized as a neurodevelopmental disorder associated with intellectual disability, epilepsy, and autism spectrum disorder. Recently, methyl-CpG-binding domain 5 gene (MBD5), located in the 2q23.1 region, has been considered as a single causative gene of this syndrome. We report on a female patient with a de novo reciprocal translocation between chromosomes 2 and 5. Chromosomal microarray testing revealed a cryptic 896 kb deletion that included MBD5. Although clinical manifestations of this patient are compatible with those of patients with 2q23.1 deletion syndrome, a focal pachygyria revealed by brain magnetic resonance imaging has never been observed in the previously reported cases. Obesity caused by hyperphagia was observed in our patient and 28% of the previously reported patients with the 2q23.1 deletion syndrome. For better medical management, appropriate dietary guidance against hyperphagia should be given to the patients' family.
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Affiliation(s)
- Minobu Shichiji
- Department of Pediatrics, Tokyo Women's Medical University, Tokyo, Japan
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Williams HJ, Monks S, Murphy KC, Kirov G, O'Donovan MC, Owen MJ. Schizophrenia two-hit hypothesis in velo-cardio facial syndrome. Am J Med Genet B Neuropsychiatr Genet 2013; 162B:177-82. [PMID: 23335482 DOI: 10.1002/ajmg.b.32129] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/14/2012] [Accepted: 12/21/2012] [Indexed: 12/12/2022]
Abstract
Deletion of chr22q11 gives rise to velo-cardio facial syndrome (VCFS) and increases schizophrenia risk. The source of this elevated risk although unknown could result from stochastic, environmental, or genetic factors, the latter encompassing a range of complexity from polygenic mechanisms to "second-hit" mutations. For this study we tested the two-hit hypothesis where additional risk is conferred through a second CNV. We identified large (>100 kb) CNVs in 48 VCFS cases (23 with psychosis--25 without) and show in the psychotic VCFS group there is a significant (P = 0.02) increase in the average size of CNVs (354-227 kb). To identify second-hit loci we focused on individuals possessing gene-centric CNVs and through literature mining identified 4 (31%) psychotic VCFS individuals (n = 13) that overlapped loci previously implicated in neuropsychiatric disorders compared to 1 (10%) from the non-psychotic VCFS individuals (n = 10). For replication 17 VCFS patients with schizophrenia from the molecular genetics of schizophrenia dataset were used to identify further CNVs. Thirteen individuals possessing gene-centric CNVs were identified including 3 (23%) individuals possessing a potential second-hit, taking the overall total in the psychotic VCFS group (n = 26) to 7 (27%) potential second-hit loci. Notably a deletion in a psychotic VCFS patient at 2q23.1 hit the gene MBD5 which when deleted gives rise to intellectual disability, epilepsy, and autistic features. Through this study we potentially extend this phenotypic spectrum to include schizophrenia. Our results suggest the two-hit hypothesis may be relevant to a proportion of VCFS patients with psychosis but sample sizes are small and further studies warranted.
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Affiliation(s)
- Hywel J Williams
- Institute of Psychological Medicine and Clinical Neurosciences, MRC Centre for Neuropsychiatric Genetics and Genomics, Cardiff University, Cardiff, UK
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Bonnet C, Ali Khan A, Bresso E, Vigouroux C, Béri M, Lejczak S, Deemer B, Andrieux J, Philippe C, Moncla A, Giurgea I, Devignes MD, Leheup B, Jonveaux P. Extended spectrum of MBD5 mutations in neurodevelopmental disorders. Eur J Hum Genet 2013; 21:1457-61. [PMID: 23422940 DOI: 10.1038/ejhg.2013.22] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2012] [Revised: 12/27/2012] [Accepted: 01/24/2013] [Indexed: 02/08/2023] Open
Abstract
Intellectual disability (ID) is a clinical sign reflecting diverse neurodevelopmental disorders that are genetically and phenotypically heterogeneous. Just recently, partial or complete deletion of methyl-CpG-binding domain 5 (MBD5) gene has been implicated as causative in the phenotype associated with 2q23.1 microdeletion syndrome. In the course of systematic whole-genome screening of individuals with unexplained ID by array-based comparative genomic hybridization, we identified de novo intragenic deletions of MBD5 in three patients leading, as previously documented, to haploinsufficiency of MBD5. In addition, we described a patient with an unreported de novo MBD5 intragenic duplication. Reverse transcriptase-PCR and sequencing analyses showed the presence of numerous aberrant transcripts leading to premature termination codon. To further elucidate the involvement of MBD5 in ID, we sequenced ten coding, five non-coding exons and an evolutionary conserved region in intron 2, in a selected cohort of 78 subjects with a phenotype reminiscent of 2q23.1 microdeletion syndrome. Besides variants most often inherited from an healthy parent, we identified for the first time a de novo nonsense mutation associated with a much more damaging phenotype. Taken together, these results extend the mutation spectrum in MBD5 gene and contribute to refine the associated phenotype of neurodevelopmental disorder.
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Affiliation(s)
- Céline Bonnet
- Laboratoire de Génétique, EA 4368, Université de Lorraine, Centre Hospitalier Universitaire de Nancy, Vandoeuvre les Nancy, France
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Copy number variants in adult patients with Lennox-Gastaut syndrome features. Epilepsy Res 2013; 105:110-7. [PMID: 23415449 DOI: 10.1016/j.eplepsyres.2013.01.009] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2012] [Revised: 12/29/2012] [Accepted: 01/18/2013] [Indexed: 12/14/2022]
Abstract
PURPOSE Lennox-Gastaut syndrome (LGS) is a severe epileptic encephalopathy with complex etiology. To explore possible genetic predispositions and causes of LGS, we have searched for copy number variants (CNVs). METHODS We studied 21 patients with LGS or LGS-like epilepsy for CNVs using whole-genome array comparative genomic hybridization (aCGH). KEY FINDINGS Eight patients (38%) carried rare CNVs that might contribute to their phenotype. The pathogenicity could be questioned in some of them, but in four patients (19%) a causative role was considered highly probable. Three had CNVs and clinical features consistent with known genetic syndromes: 22q13.3 deletion, 2q23.1 deletion, and MECP2 duplication. SIGNIFICANCE There is a high frequency of rare CNVs in adult patients with LGS-like epilepsy. The phenotypes of these background disorders may be obscured by the effects of intractable seizures and massive antiepileptic drug treatment. Previously, syndromic disorders were primarily identified by their clinical features; however, a genome wide approach with identification of the genotype might shed light on the phenotype.
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Beunders G, Voorhoeve E, Golzio C, Pardo L, Rosenfeld J, Talkowski M, Simonic I, Lionel A, Vergult S, Pyatt R, van de Kamp J, Nieuwint A, Weiss M, Rizzu P, Verwer L, van Spaendonk R, Shen Y, Wu BL, Yu T, Yu Y, Chiang C, Gusella J, Lindgren A, Morton C, van Binsbergen E, Bulk S, van Rossem E, Vanakker O, Armstrong R, Park SM, Greenhalgh L, Maye U, Neill N, Abbott K, Sell S, Ladda R, Farber D, Bader P, Cushing T, Drautz J, Konczal L, Nash P, de Los Reyes E, Carter M, Hopkins E, Marshall C, Osborne L, Gripp K, Thrush D, Hashimoto S, Gastier-Foster J, Astbury C, Ylstra B, Meijers-Heijboer H, Posthuma D, Menten B, Mortier G, Scherer S, Eichler E, Girirajan S, Katsanis N, Groffen A, Sistermans E. Exonic deletions in AUTS2 cause a syndromic form of intellectual disability and suggest a critical role for the C terminus. Am J Hum Genet 2013; 92:210-20. [PMID: 23332918 PMCID: PMC3567268 DOI: 10.1016/j.ajhg.2012.12.011] [Citation(s) in RCA: 117] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2012] [Revised: 10/06/2012] [Accepted: 12/20/2012] [Indexed: 01/15/2023] Open
Abstract
Genomic rearrangements involving AUTS2 (7q11.22) are associated with autism and intellectual disability (ID), although evidence for causality is limited. By combining the results of diagnostic testing of 49,684 individuals, we identified 24 microdeletions that affect at least one exon of AUTS2, as well as one translocation and one inversion each with a breakpoint within the AUTS2 locus. Comparison of 17 well-characterized individuals enabled identification of a variable syndromic phenotype including ID, autism, short stature, microcephaly, cerebral palsy, and facial dysmorphisms. The dysmorphic features were more pronounced in persons with 3'AUTS2 deletions. This part of the gene is shown to encode a C-terminal isoform (with an alternative transcription start site) expressed in the human brain. Consistent with our genetic data, suppression of auts2 in zebrafish embryos caused microcephaly that could be rescued by either the full-length or the C-terminal isoform of AUTS2. Our observations demonstrate a causal role of AUTS2 in neurocognitive disorders, establish a hitherto unappreciated syndromic phenotype at this locus, and show how transcriptional complexity can underpin human pathology. The zebrafish model provides a valuable tool for investigating the etiology of AUTS2 syndrome and facilitating gene-function analysis in the future.
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Affiliation(s)
- Gea Beunders
- Department of Clinical Genetics, VU University Medical Center, Amsterdam 1007 MB, The Netherlands
| | - Els Voorhoeve
- Department of Clinical Genetics, VU University Medical Center, Amsterdam 1007 MB, The Netherlands
| | - Christelle Golzio
- Center for Human Disease Modeling, Department of Cell Biology, Duke University Medical Center, Durham, NC 27710, USA
| | - Luba M. Pardo
- Department of Clinical Genetics, VU University Medical Center, Amsterdam 1007 MB, The Netherlands
| | - Jill A. Rosenfeld
- Signature Genomic Laboratories, Perkin Elmer, Spokane, WA 99207, USA
| | - Michael E. Talkowski
- Center for Human Genetic Research, Massachusetts General Hospital, affiliated with Departments of Genetics and Neurology, Harvard Medical School, Harvard University, Boston, MA 02114, USA
- Program in Medical and Population Genetics, Broad Institute, Cambridge, MA 02142, USA
| | - Ingrid Simonic
- East Anglian Medical Genetics Service, Addenbrooke’s Hospital, Cambridge University Hospitals, National Health Service Foundation Trust, Cambridge, CB2 0QQ, UK
| | - Anath C. Lionel
- The Centre for Applied Genomics and Program in Genetics and Genome Biology, The Hospital for Sick Children, Toronto, ON M5G 1L7, Canada
- Department of Molecular Genetics and the McLaughlin Centre, University of Toronto, Toronto, ON M5S 1A1, Canada
| | - Sarah Vergult
- Center for Medical Genetics, University Hospital Ghent, Ghent 9000, Belgium
| | - Robert E. Pyatt
- Pathology and Laboratory Medicine, Nationwide Children’s Hospital, Columbus, OH 43205, USA
- Department of Pathology, The Ohio State University, Columbus, OH 43210, USA
| | - Jiddeke van de Kamp
- Department of Clinical Genetics, VU University Medical Center, Amsterdam 1007 MB, The Netherlands
| | - Aggie Nieuwint
- Department of Clinical Genetics, VU University Medical Center, Amsterdam 1007 MB, The Netherlands
| | - Marjan M. Weiss
- Department of Clinical Genetics, VU University Medical Center, Amsterdam 1007 MB, The Netherlands
| | - Patrizia Rizzu
- Department of Clinical Genetics, VU University Medical Center, Amsterdam 1007 MB, The Netherlands
| | - Lucilla E.N.I. Verwer
- Department of Clinical Genetics, VU University Medical Center, Amsterdam 1007 MB, The Netherlands
| | | | - Yiping Shen
- Center for Human Genetic Research, Massachusetts General Hospital, affiliated with Departments of Genetics and Neurology, Harvard Medical School, Harvard University, Boston, MA 02114, USA
- Department of Laboratory Medicine, Boston Children’s Hospital, Boston, MA 02114, USA
- Shanghai Children’s Medical Center, Shanghai Jiaotong University School of Medicine, Shanghai 200025, China
| | - Bai-lin Wu
- Department of Laboratory Medicine, Boston Children’s Hospital, Boston, MA 02114, USA
- Children’s Hospital and Institutes of Biomedical Science, Fudan University, Shanghai 200032, China
| | - Tingting Yu
- Department of Laboratory Medicine, Boston Children’s Hospital, Boston, MA 02114, USA
- Shanghai Children’s Medical Center, Shanghai Jiaotong University School of Medicine, Shanghai 200025, China
| | - Yongguo Yu
- Department of Laboratory Medicine, Boston Children’s Hospital, Boston, MA 02114, USA
- Shanghai Children’s Medical Center, Shanghai Jiaotong University School of Medicine, Shanghai 200025, China
| | - Colby Chiang
- Center for Human Genetic Research, Massachusetts General Hospital, affiliated with Departments of Genetics and Neurology, Harvard Medical School, Harvard University, Boston, MA 02114, USA
| | - James F. Gusella
- Center for Human Genetic Research, Massachusetts General Hospital, affiliated with Departments of Genetics and Neurology, Harvard Medical School, Harvard University, Boston, MA 02114, USA
- Program in Medical and Population Genetics, Broad Institute, Cambridge, MA 02142, USA
| | - Amelia M. Lindgren
- Department of Pathology, Brigham and Women’s Hospital, Boston, MA 02115, USA
- Department of Obstetrics, Gynecology, and Reproductive Biology, Harvard Medical School, Boston, MA 02115, USA
| | - Cynthia C. Morton
- Program in Medical and Population Genetics, Broad Institute, Cambridge, MA 02142, USA
- Department of Pathology, Brigham and Women’s Hospital, Boston, MA 02115, USA
- Department of Obstetrics, Gynecology, and Reproductive Biology, Harvard Medical School, Boston, MA 02115, USA
| | - Ellen van Binsbergen
- Department of Medical Genetics, University Medical Center Utrecht, Utrecht 3508 AB, The Netherlands
| | - Saskia Bulk
- Department of Medical Genetics, University Medical Center Utrecht, Utrecht 3508 AB, The Netherlands
| | | | - Olivier Vanakker
- Center for Medical Genetics, University Hospital Ghent, Ghent 9000, Belgium
| | - Ruth Armstrong
- East Anglian Medical Genetics Service, Addenbrooke’s Hospital, Cambridge University Hospitals, National Health Service Foundation Trust, Cambridge, CB2 0QQ, UK
| | - Soo-Mi Park
- East Anglian Medical Genetics Service, Addenbrooke’s Hospital, Cambridge University Hospitals, National Health Service Foundation Trust, Cambridge, CB2 0QQ, UK
| | - Lynn Greenhalgh
- Clinical Genetics, Royal Liverpool Children’s Hospital, Eaton Road, Alder Hey, Liverpool L12 2AP, Great Britain
| | - Una Maye
- Clinical Genetics, Royal Liverpool Children’s Hospital, Eaton Road, Alder Hey, Liverpool L12 2AP, Great Britain
| | - Nicholas J. Neill
- Signature Genomic Laboratories, Perkin Elmer, Spokane, WA 99207, USA
| | - Kristin M. Abbott
- East Anglian Medical Genetics Service, Addenbrooke’s Hospital, Cambridge University Hospitals, National Health Service Foundation Trust, Cambridge, CB2 0QQ, UK
| | - Susan Sell
- Penn State Milton S. Hershey Medical Center, Hershey, PA 17033, USA
| | - Roger Ladda
- Penn State Milton S. Hershey Medical Center, Hershey, PA 17033, USA
| | - Darren M. Farber
- Department of Neurology, University of Louisville, Louisville, KY 40222, USA
| | - Patricia I. Bader
- Northeast Indiana Genetic Counseling Center, Ft. Wayne, IN 46804, USA
| | - Tom Cushing
- Pediatric Genetics Division, Department of Pediatrics, University of New Mexico, Albuquerque, NM 87131, USA
| | - Joanne M. Drautz
- Pediatric Genetics Division, Department of Pediatrics, University of New Mexico, Albuquerque, NM 87131, USA
| | - Laura Konczal
- University Hospitals, Case Western Reserve University, Cleveland, OH 44106, USA
| | - Patricia Nash
- Department of Behavioral Pediatrics, Nationwide Children’s Hospital, Columbus, OH 43205, USA
| | - Emily de Los Reyes
- Department of Pediatrics and Neurology, The Ohio State University, Columbus, OH 43210, USA
| | - Melissa T. Carter
- Division of Clinical and Metabolic Genetics, The Hospital for Sick Children, Toronto, ON M5G 1X8, Canada
| | - Elizabeth Hopkins
- Division of Medical Genetics, Alfred I. duPont Hospital for Children, Wilmington, DE 19803, USA
| | - Christian R. Marshall
- The Centre for Applied Genomics and Program in Genetics and Genome Biology, The Hospital for Sick Children, Toronto, ON M5G 1L7, Canada
- Department of Molecular Genetics and the McLaughlin Centre, University of Toronto, Toronto, ON M5S 1A1, Canada
| | - Lucy R. Osborne
- Departments of Medicine and Molecular Genetics, University of Toronto, Toronto, ON M5S 1A8, Canada
| | - Karen W. Gripp
- Division of Medical Genetics, Alfred I. duPont Hospital for Children, Wilmington, DE 19803, USA
| | - Devon Lamb Thrush
- Pathology and Laboratory Medicine, Nationwide Children’s Hospital, Columbus, OH 43205, USA
- Department of Pediatrics, The Ohio State University, Columbus, OH 43210, USA
| | - Sayaka Hashimoto
- Pathology and Laboratory Medicine, Nationwide Children’s Hospital, Columbus, OH 43205, USA
| | - Julie M. Gastier-Foster
- Pathology and Laboratory Medicine, Nationwide Children’s Hospital, Columbus, OH 43205, USA
- Department of Pathology, The Ohio State University, Columbus, OH 43210, USA
| | - Caroline Astbury
- Pathology and Laboratory Medicine, Nationwide Children’s Hospital, Columbus, OH 43205, USA
- Department of Pathology, The Ohio State University, Columbus, OH 43210, USA
| | - Bauke Ylstra
- Department of Pathology, VU University Medical Center, Amsterdam 1007 MB, The Netherlands
| | - Hanne Meijers-Heijboer
- Department of Clinical Genetics, VU University Medical Center, Amsterdam 1007 MB, The Netherlands
| | - Danielle Posthuma
- Department of Clinical Genetics, VU University Medical Center, Amsterdam 1007 MB, The Netherlands
- Department of Functional Genomics, Center for Neurogenomics and Cognitive Research, Neuroscience Campus Amsterdam, VU University, Amsterdam 1081 HV, The Netherlands
- Department of Child and Adolescent Psychiatry, Erasmus University Rotterdam, Rotterdam 3000 CB, The Netherlands
| | - Björn Menten
- Center for Medical Genetics, University Hospital Ghent, Ghent 9000, Belgium
| | - Geert Mortier
- Department of Medical Genetics, Antwerp University, Edegem 2650, Belgium
| | - Stephen W. Scherer
- The Centre for Applied Genomics and Program in Genetics and Genome Biology, The Hospital for Sick Children, Toronto, ON M5G 1L7, Canada
- Department of Molecular Genetics and the McLaughlin Centre, University of Toronto, Toronto, ON M5S 1A1, Canada
| | - Evan E. Eichler
- Department of Genome Sciences and Howard Hughes Medical Institute, University of Washington, Seattle, WA 98195, USA
| | - Santhosh Girirajan
- Department of Genome Sciences and Howard Hughes Medical Institute, University of Washington, Seattle, WA 98195, USA
- Department of Biochemistry and Molecular Biology Department of Anthropology, Pennsylvania State University, Pennsylvania, PA 16803, USA
| | - Nicholas Katsanis
- Center for Human Disease Modeling, Department of Cell Biology, Duke University Medical Center, Durham, NC 27710, USA
| | - Alexander J. Groffen
- Department of Clinical Genetics, VU University Medical Center, Amsterdam 1007 MB, The Netherlands
- Department of Functional Genomics, Center for Neurogenomics and Cognitive Research, Neuroscience Campus Amsterdam, VU University, Amsterdam 1081 HV, The Netherlands
| | - Erik A. Sistermans
- Department of Clinical Genetics, VU University Medical Center, Amsterdam 1007 MB, The Netherlands
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Du Y, Liu B, Guo F, Xu G, Ding Y, Liu Y, Sun X, Xu G. The essential role of Mbd5 in the regulation of somatic growth and glucose homeostasis in mice. PLoS One 2012; 7:e47358. [PMID: 23077600 PMCID: PMC3471830 DOI: 10.1371/journal.pone.0047358] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2012] [Accepted: 09/11/2012] [Indexed: 12/16/2022] Open
Abstract
Methyl-CpG binding domain protein 5 (MBD5) belongs to the MBD family proteins, which play central roles in transcriptional regulation and development. The significance of MBD5 function is highlighted by recent studies implicating it as a candidate gene involved in human 2q23.1 microdeletion syndrome. To investigate the physiological role of Mbd5, we generated knockout mice. The Mbd5-deficient mice showed growth retardation, wasting and pre-weaning lethality. The observed growth retardation was associated with the impairment of GH/IGF-1 axis in Mbd5-null pups. Conditional knockout of Mbd5 in the brain resulted in the similar phenotypes as whole body deletion, indicating that Mbd5 functions in the nervous system to regulate postnatal growth. Moreover, the mutant mice also displayed enhanced glucose tolerance and elevated insulin sensitivity as a result of increased insulin signaling, ultimately resulting in disturbed glucose homeostasis and hypoglycemia. These results indicate Mbd5 as an essential factor for mouse postnatal growth and maintenance of glucose homeostasis.
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Affiliation(s)
- Yarui Du
- The State Key Laboratory of Molecular Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, People’s Republic of China
| | - Bo Liu
- The State Key Laboratory of Molecular Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, People’s Republic of China
| | - Fan Guo
- The State Key Laboratory of Molecular Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, People’s Republic of China
| | - Guifang Xu
- The State Key Laboratory of Molecular Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, People’s Republic of China
| | - Yuqiang Ding
- Tongji University School of Medicine, Shanghai, People’s Republic of China
| | - Yong Liu
- Institute of Nutrition Sciences, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, People’s Republic of China
| | - Xin Sun
- Laboratory of Genetics, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
| | - Guoliang Xu
- The State Key Laboratory of Molecular Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, People’s Republic of China
- * E-mail:
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Cukier HN, Lee JM, Ma D, Young JI, Mayo V, Butler BL, Ramsook SS, Rantus JA, Abrams AJ, Whitehead PL, Wright HH, Abramson RK, Haines JL, Cuccaro ML, Pericak-Vance MA, Gilbert JR. The expanding role of MBD genes in autism: identification of a MECP2 duplication and novel alterations in MBD5, MBD6, and SETDB1. Autism Res 2012; 5:385-97. [PMID: 23055267 DOI: 10.1002/aur.1251] [Citation(s) in RCA: 63] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2012] [Accepted: 08/02/2012] [Indexed: 01/09/2023]
Abstract
The methyl-CpG-binding domain (MBD) gene family was first linked to autism over a decade ago when Rett syndrome, which falls under the umbrella of autism spectrum disorders (ASDs), was revealed to be predominantly caused by MECP2 mutations. Since that time, MECP2 alterations have been recognized in idiopathic ASD patients by us and others. Individuals with deletions across the MBD5 gene also present with ASDs, impaired speech, intellectual difficulties, repetitive behaviors, and epilepsy. These findings suggest that further investigations of the MBD gene family may reveal additional associations related to autism. We now describe the first study evaluating individuals with ASD for rare variants in four autosomal MBD family members, MBD5, MBD6, SETDB1, and SETDB2, and expand our initial screening in the MECP2 gene. Each gene was sequenced over all coding exons and evaluated for copy number variations in 287 patients with ASD and an equal number of ethnically matched control individuals. We identified 186 alterations through sequencing, approximately half of which were novel (96 variants, 51.6%). We identified 17 ASD specific, nonsynonymous variants, four of which were concordant in multiplex families: MBD5 Tyr1269Cys, MBD6 Arg883Trp, MECP2 Thr240Ser, and SETDB1 Pro1067del. Furthermore, a complex duplication spanning of the MECP2 gene was identified in two brothers who presented with developmental delay and intellectual disability. From our studies, we provide the first examples of autistic patients carrying potentially detrimental alterations in MBD6 and SETDB1, thereby demonstrating that the MBD gene family potentially plays a significant role in rare and private genetic causes of autism.
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Affiliation(s)
- Holly N Cukier
- John P. Hussman Institute for Human Genomics, University of Miami, Miller School of Medicine, Miami, FL 33136, USA
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Kleefstra T, Kramer J, Neveling K, Willemsen M, Koemans T, Vissers L, Wissink-Lindhout W, Fenckova M, van den Akker W, Kasri N, Nillesen W, Prescott T, Clark R, Devriendt K, van Reeuwijk J, de Brouwer A, Gilissen C, Zhou H, Brunner H, Veltman J, Schenck A, van Bokhoven H. Disruption of an EHMT1-associated chromatin-modification module causes intellectual disability. Am J Hum Genet 2012; 91:73-82. [PMID: 22726846 DOI: 10.1016/j.ajhg.2012.05.003] [Citation(s) in RCA: 182] [Impact Index Per Article: 15.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2012] [Revised: 04/10/2012] [Accepted: 05/14/2012] [Indexed: 12/22/2022] Open
Abstract
Intellectual disability (ID) disorders are genetically and phenotypically highly heterogeneous and present a major challenge in clinical genetics and medicine. Although many genes involved in ID have been identified, the etiology is unknown in most affected individuals. Moreover, the function of most genes associated with ID remains poorly characterized. Evidence is accumulating that the control of gene transcription through epigenetic modification of chromatin structure in neurons has an important role in cognitive processes and in the etiology of ID. However, our understanding of the key molecular players and mechanisms in this process is highly fragmentary. Here, we identify a chromatin-modification module that underlies a recognizable form of ID, the Kleefstra syndrome phenotypic spectrum (KSS). In a cohort of KSS individuals without mutations in EHMT1 (the only gene known to be disrupted in KSS until now), we identified de novo mutations in four genes, MBD5, MLL3, SMARCB1, and NR1I3, all of which encode epigenetic regulators. Using Drosophila, we demonstrate that MBD5, MLL3, and NR1I3 cooperate with EHMT1, whereas SMARCB1 is known to directly interact with MLL3. We propose a highly conserved epigenetic network that underlies cognition in health and disease. This network should allow the design of strategies to treat the growing group of ID pathologies that are caused by epigenetic defects.
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Noh GJ, Graham JM. 2q23.1 microdeletion of the MBD5 gene in a female with seizures, developmental delay and distinct dysmorphic features. Eur J Med Genet 2012; 55:354-7. [PMID: 22659271 DOI: 10.1016/j.ejmg.2012.05.003] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2011] [Accepted: 10/04/2011] [Indexed: 01/20/2023]
Abstract
We report a 2-year-old female who initially presented with seizures, developmental delay and dysmorphic features and was found to have a 0.3 Mb deletion at chromosome 2q23.1 encompassing the critical seizure gene, MBD5. Her distinct physical features include bifrontal narrowing with brachycephaly, low anterior hairline, hypotonic facial features with short upturned nose, flat nasal bridge, hypertelorism, tented upper lip with everted lower lip, downturned corners of her mouth, and relatively coarse facial features including thickened tongue. She also had a short neck, brachytelephalangy, clinodactyly, and hypertrichosis. At 3½ years she developed progressive ataxia and lost vocabulary at the age of 4. Regression has been reported in one other case of MBD5 deletion. MBD5 is a member of the methyl binding gene family and appears to be responsible for regulating DNA methylation in the central nervous system. Our patient was entirely deleted for the MBD5 gene with partial loss of the EPC2 gene, which suggests that haploinsufficiency of MBD5 is responsible for the distinct phenotype observed. This supports the hypothesis that MBD5 is indeed the critical gene implicated for the findings seen in patients with deletions of chromosome 2q23.1. Further studies are necessary to delineate the role that the MBD5 gene plays in the development of the brain and these specific physical characteristics.
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Affiliation(s)
- Grace J Noh
- Medical Genetics Institute, Cedars-Sinai Medical Center, 8700 Beverly Blvd, Los Angeles, CA 90048, USA
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A genetic model for neurodevelopmental disease. Curr Opin Neurobiol 2012; 22:829-36. [PMID: 22560351 PMCID: PMC3437230 DOI: 10.1016/j.conb.2012.04.007] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2012] [Revised: 02/16/2012] [Accepted: 04/05/2012] [Indexed: 12/20/2022]
Abstract
The genetic basis of neurodevelopmental and neuropsychiatric diseases has been advanced by the discovery of large and recurrent copy number variants significantly enriched in cases when compared to controls. The pattern of this variation strongly implies that rare variants contribute significantly to neurological disease; that different genes will be responsible for similar diseases in different families; and that the same 'primary' genetic lesions can result in a different disease outcome depending potentially on the genetic background. Next-generation sequencing technologies are beginning to broaden the spectrum of disease-causing variation and provide specificity by pinpointing both genes and pathways for future diagnostics and therapeutics.
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Talkowski ME, Rosenfeld JA, Blumenthal I, Pillalamarri V, Chiang C, Heilbut A, Ernst C, Hanscom C, Rossin E, Lindgren A, Pereira S, Ruderfer D, Kirby A, Ripke S, Harris D, Lee JH, Ha K, Kim HG, Solomon BD, Gropman AL, Lucente D, Sims K, Ohsumi TK, Borowsky ML, Loranger S, Quade B, Lage K, Miles J, Wu BL, Shen Y, Neale B, Shaffer LG, Daly MJ, Morton CC, Gusella JF. Sequencing chromosomal abnormalities reveals neurodevelopmental loci that confer risk across diagnostic boundaries. Cell 2012; 149:525-37. [PMID: 22521361 PMCID: PMC3340505 DOI: 10.1016/j.cell.2012.03.028] [Citation(s) in RCA: 434] [Impact Index Per Article: 36.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2011] [Revised: 02/27/2012] [Accepted: 03/28/2012] [Indexed: 01/18/2023]
Abstract
Balanced chromosomal abnormalities (BCAs) represent a relatively untapped reservoir of single-gene disruptions in neurodevelopmental disorders (NDDs). We sequenced BCAs in patients with autism or related NDDs, revealing disruption of 33 loci in four general categories: (1) genes previously associated with abnormal neurodevelopment (e.g., AUTS2, FOXP1, and CDKL5), (2) single-gene contributors to microdeletion syndromes (MBD5, SATB2, EHMT1, and SNURF-SNRPN), (3) novel risk loci (e.g., CHD8, KIRREL3, and ZNF507), and (4) genes associated with later-onset psychiatric disorders (e.g., TCF4, ZNF804A, PDE10A, GRIN2B, and ANK3). We also discovered among neurodevelopmental cases a profoundly increased burden of copy-number variants from these 33 loci and a significant enrichment of polygenic risk alleles from genome-wide association studies of autism and schizophrenia. Our findings suggest a polygenic risk model of autism and reveal that some neurodevelopmental genes are sensitive to perturbation by multiple mutational mechanisms, leading to variable phenotypic outcomes that manifest at different life stages.
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Affiliation(s)
- Michael E. Talkowski
- Center for Human Genetic Research, Massachusetts General Hospital, Boston, MA
- Department of Neurology, Harvard Medical School, Boston, MA
- Program in Medical and Population Genetics, Broad Institute, Cambridge, MA
| | | | - Ian Blumenthal
- Center for Human Genetic Research, Massachusetts General Hospital, Boston, MA
| | - Vamsee Pillalamarri
- Center for Human Genetic Research, Massachusetts General Hospital, Boston, MA
| | - Colby Chiang
- Center for Human Genetic Research, Massachusetts General Hospital, Boston, MA
| | - Adrian Heilbut
- Center for Human Genetic Research, Massachusetts General Hospital, Boston, MA
| | - Carl Ernst
- Center for Human Genetic Research, Massachusetts General Hospital, Boston, MA
| | - Carrie Hanscom
- Center for Human Genetic Research, Massachusetts General Hospital, Boston, MA
| | - Elizabeth Rossin
- Center for Human Genetic Research, Massachusetts General Hospital, Boston, MA
- Program in Medical and Population Genetics, Broad Institute, Cambridge, MA
- Analytical and Translational Genetics Unit, Massachusetts General Hospital, Boston, MA
| | - Amelia Lindgren
- Departments of Obstetrics, Gynecology and Reproductive Biology, Brigham and Women’s Hospital, Boston, MA
| | - Shahrin Pereira
- Departments of Obstetrics, Gynecology and Reproductive Biology, Brigham and Women’s Hospital, Boston, MA
| | - Douglas Ruderfer
- Center for Human Genetic Research, Massachusetts General Hospital, Boston, MA
- Program in Medical and Population Genetics, Broad Institute, Cambridge, MA
| | - Andrew Kirby
- Center for Human Genetic Research, Massachusetts General Hospital, Boston, MA
- Program in Medical and Population Genetics, Broad Institute, Cambridge, MA
- Analytical and Translational Genetics Unit, Massachusetts General Hospital, Boston, MA
| | - Stephan Ripke
- Center for Human Genetic Research, Massachusetts General Hospital, Boston, MA
- Program in Medical and Population Genetics, Broad Institute, Cambridge, MA
- Analytical and Translational Genetics Unit, Massachusetts General Hospital, Boston, MA
| | - David Harris
- Division of Clinical Genetics, Children’s Hospital of Boston, Boston, MA
| | - Ji-Hyun Lee
- Center for Human Genetic Research, Massachusetts General Hospital, Boston, MA
| | - Kyungsoo Ha
- Cancer Research Center, Georgia Health Sciences University, Augusta, GA
| | - Hyung-Goo Kim
- Department of OB/GYN, IMMAG, Georgia Health Sciences University, Augusta, GA
| | - Benjamin D. Solomon
- Medical Genetics Branch, National Human Genome Research Institute, Bethesda, MD, USA
| | - Andrea L. Gropman
- Department of Neurology, Children’s National Medical Center, Washington, DC, USA
- Department of Neurology, George Washington University of Health Sciences, Washington, DC, USA
| | - Diane Lucente
- Center for Human Genetic Research, Massachusetts General Hospital, Boston, MA
| | - Katherine Sims
- Center for Human Genetic Research, Massachusetts General Hospital, Boston, MA
| | - Toshiro K. Ohsumi
- Department of Molecular Biology, Massachusetts General Hospital, Boston, MA
| | - Mark L. Borowsky
- Department of Molecular Biology, Massachusetts General Hospital, Boston, MA
| | | | - Bradley Quade
- Department of Pathology, Massachusetts General Hospital, Boston, MA
| | - Kasper Lage
- Program in Medical and Population Genetics, Broad Institute, Cambridge, MA
- Analytical and Translational Genetics Unit, Massachusetts General Hospital, Boston, MA
- Pediatric Surgical Research Laboratories, MassGeneral Hospital for Children, Massachusetts General Hospital, Boston, MA, USA
- Center for Biological Sequence Analysis, Department of Systems Biology, Technical University of Denmark, Lyngby, Denmark
- Center for Protein Research, University of Copenhagen, Copenhagen, Denmark
| | - Judith Miles
- Departments of Pediatrics, Medical Genetics & Pathology, The Thompson Center for Autism & Neurodevelopmental Disorders, University of Missouri Hospitals and Clinics, Columbia, MO
| | - Bai-Lin Wu
- Department of Pathology, Massachusetts General Hospital, Boston, MA
- Department of Laboratory Medicine, Children’s Hospital Boston, Boston, MA
- Children’s Hospital and Institutes of Biomedical Science, Fudan University, Shanghai, China
| | - Yiping Shen
- Center for Human Genetic Research, Massachusetts General Hospital, Boston, MA
- Department of Pathology, Massachusetts General Hospital, Boston, MA
- Department of Laboratory Medicine, Children’s Hospital Boston, Boston, MA
- Shanghai Children’s Medical Center, Shanghai Jiaotong University School of Medicine, Shanghai, China
| | - Benjamin Neale
- Center for Human Genetic Research, Massachusetts General Hospital, Boston, MA
- Program in Medical and Population Genetics, Broad Institute, Cambridge, MA
- Analytical and Translational Genetics Unit, Massachusetts General Hospital, Boston, MA
| | - Lisa G. Shaffer
- Signature Genomic Laboratories, PerkinElmer, Inc., Spokane, WA
| | - Mark J. Daly
- Center for Human Genetic Research, Massachusetts General Hospital, Boston, MA
- Program in Medical and Population Genetics, Broad Institute, Cambridge, MA
- Analytical and Translational Genetics Unit, Massachusetts General Hospital, Boston, MA
- Autism Consortium of Boston, Boston, MA
| | - Cynthia C. Morton
- Program in Medical and Population Genetics, Broad Institute, Cambridge, MA
- Departments of Obstetrics, Gynecology and Reproductive Biology, Brigham and Women’s Hospital, Boston, MA
- Department of Pathology, Massachusetts General Hospital, Boston, MA
| | - James F. Gusella
- Center for Human Genetic Research, Massachusetts General Hospital, Boston, MA
- Program in Medical and Population Genetics, Broad Institute, Cambridge, MA
- Autism Consortium of Boston, Boston, MA
- Department of Genetics, Harvard Medical School, Boston, MA
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Abstract
DNA methylation and chromatin modifications regulate gene expression and contribute to changes in brain transcriptomes underlying neurodevelopmental and psychiatric disorders. Clinical genetics and preclinical animal models highlight the crucial importance of the correct establishment of epigenetic marks during sensitive windows of development for normal brain function. On the same side of the coin, some of the concerned factors also appear engaged in the programming of experience-dependent long-term effects on mental health following exposure to relevant early-life events. Delineating the particular role of genetic variations in these players could provide new insights into the molecular basis of vulnerability and resilience and advance tailored therapies.
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Motobayashi M, Nishimura-Tadaki A, Inaba Y, Kosho T, Miyatake S, Niimi T, Nishimura T, Wakui K, Fukushima Y, Matsumoto N, Koike K. Neurodevelopmental features in 2q23.1 microdeletion syndrome: report of a new patient with intractable seizures and review of literature. Am J Med Genet A 2012; 158A:861-8. [PMID: 22407754 DOI: 10.1002/ajmg.a.35235] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2011] [Accepted: 12/23/2011] [Indexed: 12/14/2022]
Abstract
2q23.1 microdeletion syndrome is a recently characterized chromosomal aberration disorder uncovered through array comparative genomic hybridization (array CGH). Although the cardinal feature is intellectual disability (ID), neurodevelopmental features of the syndrome have not been systematically reviewed. We present a 5-year-old boy with severe psychomotor developmental delay/ID, progressive microcephaly with brain atrophy, growth retardation, and several external anomalies. He manifested intractable epilepsy, effectively treated with combined antiepileptic drug therapy including topiramate. Array CGH demonstrated a de novo interstitial deletion of approximately 1 Mb at 2q23.1-q23.2, involving four genes including MBD5. Nineteen patients have been reported to have the syndrome, including present patient. All patients whose data were available had ID, 17 patients (89%) had seizures, and microcephaly was evident in 9 of 18 patients (50%). Deletion sizes ranged from 200 kb to 5.5 Mb, comprising 1-15 genes. MBD5, the only gene deleted in all patients, is considered to be responsible for ID and epilepsy. Furthermore, the deletion junction was sequenced for the first time in a patient with the syndrome; and homology of three nucleotides, identified at the distal and proximal breakpoints, suggested that the deletion might have been mediated by recently-delineated genomic rearrangement mechanism Fork Stalling and Template Switching (FoSTeS)/microhomology-mediated break-induced replication (MMBIR).
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Affiliation(s)
- Mitsuo Motobayashi
- Department of Pediatrics, Shinshu University School of Medicine, Matsumoto, Japan
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Ladha S. Getting to the bottom of autism spectrum and related disorders: MBD5 as a key contributor. Clin Genet 2012; 81:363-4. [PMID: 22171639 DOI: 10.1111/j.1399-0004.2011.01836.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Affiliation(s)
- S Ladha
- Department of Medical Genetics, Centre for Molecular Medicine and Therapeutics, University of British Columbia, 980 West 28th Avenue, Vancouver, BC, Canada.
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