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Rao S, Liang F, Herring BE. RhoGEF Tiam2 Regulates Glutamatergic Synaptic Transmission in Hippocampal CA1 Pyramidal Neurons. eNeuro 2024; 11:ENEURO.0500-21.2024. [PMID: 38871458 PMCID: PMC11262554 DOI: 10.1523/eneuro.0500-21.2024] [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: 12/03/2021] [Revised: 03/29/2024] [Accepted: 05/23/2024] [Indexed: 06/15/2024] Open
Abstract
Glutamatergic synapses exhibit significant molecular diversity, but circuit-specific mechanisms that underlie synaptic regulation are not well characterized. Prior reports show that Rho-guanine nucleotide exchange factor (RhoGEF) Tiam1 regulates perforant path→dentate gyrus granule neuron synapses. In the present study, we report Tiam1's homolog Tiam2 is implicated in glutamatergic neurotransmission in CA1 pyramidal neurons. We find that Tiam2 regulates evoked excitatory glutamatergic currents via a postsynaptic mechanism mediated by the catalytic Dbl-homology domain. Overall, we present evidence for RhoGEF Tiam2's role in glutamatergic synapse function at Schaffer collateral→CA1 pyramidal neuron synapses.
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Affiliation(s)
- Sadhna Rao
- Department of Biological Sciences, Neurobiology Section, Dornsife College of Letters, Arts and Sciences, University of Southern California, Los Angeles, California 90089
| | - Feng Liang
- Department of Biological Sciences, Neurobiology Section, Dornsife College of Letters, Arts and Sciences, University of Southern California, Los Angeles, California 90089
| | - Bruce E Herring
- Department of Biological Sciences, Neurobiology Section, Dornsife College of Letters, Arts and Sciences, University of Southern California, Los Angeles, California 90089
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2
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Loe-Mie Y, Plançon C, Dubertret C, Yoshikawa T, Yalcin B, Collins SC, Boland A, Deleuze JF, Gorwood P, Benmessaoud D, Simonneau M, Lepagnol-Bestel AM. De Novo Variants Found in Three Distinct Schizophrenia Populations Hit a Common Core Gene Network Related to Microtubule and Actin Cytoskeleton Gene Ontology Classes. Life (Basel) 2024; 14:244. [PMID: 38398753 PMCID: PMC10890674 DOI: 10.3390/life14020244] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2023] [Revised: 01/29/2024] [Accepted: 02/01/2024] [Indexed: 02/25/2024] Open
Abstract
Schizophrenia (SZ) is a heterogeneous and debilitating psychiatric disorder with a strong genetic component. To elucidate functional networks perturbed in schizophrenia, we analysed a large dataset of whole-genome studies that identified SNVs, CNVs, and a multi-stage schizophrenia genome-wide association study. Our analysis identified three subclusters that are interrelated and with small overlaps: GO:0007017~Microtubule-Based Process, GO:00015629~Actin Cytoskeleton, and GO:0007268~SynapticTransmission. We next analysed three distinct trio cohorts of 75 SZ Algerian, 45 SZ French, and 61 SZ Japanese patients. We performed Illumina HiSeq whole-exome sequencing and identified de novo mutations using a Bayesian approach. We validated 88 de novo mutations by Sanger sequencing: 35 in French, 21 in Algerian, and 32 in Japanese SZ patients. These 88 de novo mutations exhibited an enrichment in genes encoding proteins related to GO:0051015~actin filament binding (p = 0.0011) using David, and enrichments in GO: 0003774~transport (p = 0.019) and GO:0003729~mRNA binding (p = 0.010) using Amigo. One of these de novo variant was found in CORO1C coding sequence. We studied Coro1c haploinsufficiency in a Coro1c+/- mouse and found defects in the corpus callosum. These results could motivate future studies of the mechanisms surrounding genes encoding proteins involved in transport and the cytoskeleton, with the goal of developing therapeutic intervention strategies for a subset of SZ cases.
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Affiliation(s)
- Yann Loe-Mie
- Université Paris Cité, Institute of Psychiatry and Neuroscience of Paris (IPNP), INSERM U1266, 75014 Paris, France; (Y.L.-M.); (C.D.); (P.G.); (A.-M.L.-B.)
| | - Christine Plançon
- Université Paris-Saclay, CEA, Centre National de Recherche en Génomique Humaine (CNRGH), 91057 Evry, France; (C.P.); (A.B.); (J.-F.D.)
| | - Caroline Dubertret
- Université Paris Cité, Institute of Psychiatry and Neuroscience of Paris (IPNP), INSERM U1266, 75014 Paris, France; (Y.L.-M.); (C.D.); (P.G.); (A.-M.L.-B.)
- AP-HP, Department of Psychiatry, Louis Mourier Hospital, 92700 Colombes, France
| | - Takeo Yoshikawa
- Laboratory for Molecular Psychiatry, RIKEN Center for Brain Science, Saitama 351-0106, Japan;
| | - Binnaz Yalcin
- Université de Bourgogne, INSERM Research Center U1231, 21000 Dijon, France; (B.Y.); (S.C.C.)
| | - Stephan C. Collins
- Université de Bourgogne, INSERM Research Center U1231, 21000 Dijon, France; (B.Y.); (S.C.C.)
| | - Anne Boland
- Université Paris-Saclay, CEA, Centre National de Recherche en Génomique Humaine (CNRGH), 91057 Evry, France; (C.P.); (A.B.); (J.-F.D.)
| | - Jean-François Deleuze
- Université Paris-Saclay, CEA, Centre National de Recherche en Génomique Humaine (CNRGH), 91057 Evry, France; (C.P.); (A.B.); (J.-F.D.)
| | - Philip Gorwood
- Université Paris Cité, Institute of Psychiatry and Neuroscience of Paris (IPNP), INSERM U1266, 75014 Paris, France; (Y.L.-M.); (C.D.); (P.G.); (A.-M.L.-B.)
- GHU-Paris Psychiatrie et Neurosciences, Hôpital Sainte Anne, 75014 Paris, France
| | - Dalila Benmessaoud
- Etablissement Hospitalo-Universitaire Spécialisé Psychiatrie Frantz FANON, Université Saad DAHLAB, Blida 09000, Algeria;
| | - Michel Simonneau
- Université Paris Cité, Institute of Psychiatry and Neuroscience of Paris (IPNP), INSERM U1266, 75014 Paris, France; (Y.L.-M.); (C.D.); (P.G.); (A.-M.L.-B.)
- Laboratoire LuMin, FRE 2036, Universite Paris-Saclay, CNRS, ENS Paris Saclay 4 Avenue des Sciences, 91190 Gif-sur-Yvette, France
- Department of Biology, Ecole Normale Supérieure de Paris-Saclay, Université Paris-Saclay, 4 Avenue des Sciences, 91190 Gif-sur-Yvette, France
| | - Aude-Marie Lepagnol-Bestel
- Université Paris Cité, Institute of Psychiatry and Neuroscience of Paris (IPNP), INSERM U1266, 75014 Paris, France; (Y.L.-M.); (C.D.); (P.G.); (A.-M.L.-B.)
- Université Paris-Saclay, CEA, Centre National de Recherche en Génomique Humaine (CNRGH), 91057 Evry, France; (C.P.); (A.B.); (J.-F.D.)
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3
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Zoghbi AW, Dhindsa RS, Goldberg TE, Mehralizade A, Motelow JE, Wang X, Alkelai A, Harms MB, Lieberman JA, Markx S, Goldstein DB. High-impact rare genetic variants in severe schizophrenia. Proc Natl Acad Sci U S A 2021; 118:e2112560118. [PMID: 34903660 PMCID: PMC8713775 DOI: 10.1073/pnas.2112560118] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/04/2021] [Indexed: 02/04/2023] Open
Abstract
Extreme phenotype sequencing has led to the identification of high-impact rare genetic variants for many complex disorders but has not been applied to studies of severe schizophrenia. We sequenced 112 individuals with severe, extremely treatment-resistant schizophrenia, 218 individuals with typical schizophrenia, and 4,929 controls. We compared the burden of rare, damaging missense and loss-of-function variants between severe, extremely treatment-resistant schizophrenia, typical schizophrenia, and controls across mutation intolerant genes. Individuals with severe, extremely treatment-resistant schizophrenia had a high burden of rare loss-of-function (odds ratio, 1.91; 95% CI, 1.39 to 2.63; P = 7.8 × 10-5) and damaging missense variants in intolerant genes (odds ratio, 2.90; 95% CI, 2.02 to 4.15; P = 3.2 × 10-9). A total of 48.2% of individuals with severe, extremely treatment-resistant schizophrenia carried at least one rare, damaging missense or loss-of-function variant in intolerant genes compared to 29.8% of typical schizophrenia individuals (odds ratio, 2.18; 95% CI, 1.33 to 3.60; P = 1.6 × 10-3) and 25.4% of controls (odds ratio, 2.74; 95% CI, 1.85 to 4.06; P = 2.9 × 10-7). Restricting to genes previously associated with schizophrenia risk strengthened the enrichment with 8.9% of individuals with severe, extremely treatment-resistant schizophrenia carrying a damaging missense or loss-of-function variant compared to 2.3% of typical schizophrenia (odds ratio, 5.48; 95% CI, 1.52 to 19.74; P = 0.02) and 1.6% of controls (odds ratio, 5.82; 95% CI, 3.00 to 11.28; P = 2.6 × 10-8). These results demonstrate the power of extreme phenotype case selection in psychiatric genetics and an approach to augment schizophrenia gene discovery efforts.
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Affiliation(s)
- Anthony W Zoghbi
- Menninger Department of Psychiatry and Behavioral Sciences, Baylor College of Medicine, Houston, TX 77030;
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030
- Department of Psychiatry, Columbia University Irving Medical Center, New York State Psychiatric Institute, New York, NY 10032
- Institute of Genomic Medicine, Columbia University Irving Medical Center, New York, NY 10032
- Office of Mental Health, New York State Psychiatric Institute, New York, NY 10032
| | - Ryan S Dhindsa
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030
- Institute of Genomic Medicine, Columbia University Irving Medical Center, New York, NY 10032
- Department of Molecular and Human Genetics, Jan and Dan Duncan Neurological Research Institute, Houston, TX 77030
- Department of Genetics and Development, Columbia University Irving Medical Center, New York, NY 10032
| | - Terry E Goldberg
- Department of Psychiatry, Columbia University Irving Medical Center, New York State Psychiatric Institute, New York, NY 10032
- Office of Mental Health, New York State Psychiatric Institute, New York, NY 10032
- Department of Anesthesiology, Columbia University Irving Medical Center, New York, NY 10032
| | - Aydan Mehralizade
- Department of Psychiatry, Columbia University Irving Medical Center, New York State Psychiatric Institute, New York, NY 10032
- Office of Mental Health, New York State Psychiatric Institute, New York, NY 10032
| | - Joshua E Motelow
- Institute of Genomic Medicine, Columbia University Irving Medical Center, New York, NY 10032
- Department of Genetics and Development, Columbia University Irving Medical Center, New York, NY 10032
- Department of Pediatrics, Division of Critical Care and Hospital Medicine, Columbia University Irving Medical Center, New York-Presbyterian Morgan Stanley Children's Hospital of New York, New York, NY 10032
| | - Xinchen Wang
- Institute of Genomic Medicine, Columbia University Irving Medical Center, New York, NY 10032
- Department of Genetics and Development, Columbia University Irving Medical Center, New York, NY 10032
- Waypoint Bio, New York, NY 10014
| | - Anna Alkelai
- Institute of Genomic Medicine, Columbia University Irving Medical Center, New York, NY 10032
- Department of Genetics and Development, Columbia University Irving Medical Center, New York, NY 10032
| | - Matthew B Harms
- Institute of Genomic Medicine, Columbia University Irving Medical Center, New York, NY 10032
- Department of Neurology, Columbia University Irving Medical Center, New York, NY 10032
- Center for Motor Neuron Biology and Disease, Columbia University Irving Medical Center, New York, NY 10032
| | - Jeffrey A Lieberman
- Department of Psychiatry, Columbia University Irving Medical Center, New York State Psychiatric Institute, New York, NY 10032
- Office of Mental Health, New York State Psychiatric Institute, New York, NY 10032
| | - Sander Markx
- Department of Psychiatry, Columbia University Irving Medical Center, New York State Psychiatric Institute, New York, NY 10032;
- Office of Mental Health, New York State Psychiatric Institute, New York, NY 10032
| | - David B Goldstein
- Institute of Genomic Medicine, Columbia University Irving Medical Center, New York, NY 10032;
- Department of Genetics and Development, Columbia University Irving Medical Center, New York, NY 10032
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Fonseca L, Sena BF, Crossley N, Lopez-Jaramillo C, Koenen K, Freimer NB, Bressan RA, Belangero SI, Santoro ML, Gadelha A. Diversity matters: opportunities in the study of the genetics of psychotic disorders in low- and middle-income countries in Latin America. ACTA ACUST UNITED AC 2020; 43:631-637. [PMID: 33237255 PMCID: PMC8639010 DOI: 10.1590/1516-4446-2020-1240] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2020] [Accepted: 09/22/2020] [Indexed: 01/15/2023]
Abstract
Lack of diversity regarding genetic and environmental backgrounds weakens the generalization and clinical applicability of research findings on psychotic disorders. Notably, Latin Americans have been generally neglected in genetic studies, comprising less than 2% of genome-wide association study samples. But Latin American populations represent a unique opportunity for research, given the exceptionally high ethnic admixture of this group. Increasing genetic diversity is essential to improve the fine mapping of known regions associated with psychotic disorders, discover novel genetic associations, and replicate studies. Additionally, Latin America is characterized by massive social, political, and economic inequalities, all known risk factors for mental health issues, including psychotic disorders. This article aims to 1) discuss the challenges and advantages of studying Latin America’s particular genetic makeup and environmental context; 2) review previous studies conducted in the region; and 3) describe three Latin American research initiatives in progress: the Neuropsychiatric Genetics of Psychosis in Mexican Populations (NeuroMEX), the Paisa, and the Latin American Network for the Study of Early Psychosis (ANDES) studies.
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Affiliation(s)
- Lais Fonseca
- Laboratório Interdisciplinar de Neurociências Clínicas (LiNC), Universidade Federal de São Paulo (UNIFESP), São Paulo, SP, Brazil.,Programa de Esquizofrenia (PROESQ), Departamento de Psiquiatria, UNIFESP, São Paulo, SP, Brazil
| | - Brena F Sena
- Department of Epidemiology, Harvard T.H. Chan School of Public Health, Boston, MA, USA.,Stanley Center for Psychiatric Research, Broad Institute, Massachusetts Institute of Technology (MIT) and Harvard, Cambridge, MA, USA
| | - Nicolas Crossley
- Department of Psychiatry, School of Medicine, Pontificia Universidad Católica de Chile, Santiago, Chile.,Department of Psychosis Studies, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK
| | - Carlos Lopez-Jaramillo
- Research Group in Psychiatry, Department of Psychiatry, School of Medicine, Universidad de Antioquia, Medellin, Colombia.,Mood Disorders Program, Hospital San Vicente Fundación, Medellin, Colombia
| | - Karestan Koenen
- Department of Epidemiology, Harvard T.H. Chan School of Public Health, Boston, MA, USA.,Stanley Center for Psychiatric Research, Broad Institute, Massachusetts Institute of Technology (MIT) and Harvard, Cambridge, MA, USA
| | - Nelson B Freimer
- Department of Psychiatry and Biobehavioral Sciences, University of California (UCLA), Los Angeles, CA, USA.,Center for Neurobehavioral Genetics, Semel Institute for Neuroscience and Human Behavior, UCLA, Los Angeles, CA, USA.,Department of Human Genetics, UCLA, Los Angeles, CA, USA
| | - Rodrigo A Bressan
- Laboratório Interdisciplinar de Neurociências Clínicas (LiNC), Universidade Federal de São Paulo (UNIFESP), São Paulo, SP, Brazil.,Programa de Esquizofrenia (PROESQ), Departamento de Psiquiatria, UNIFESP, São Paulo, SP, Brazil
| | - Sintia I Belangero
- Laboratório Interdisciplinar de Neurociências Clínicas (LiNC), Universidade Federal de São Paulo (UNIFESP), São Paulo, SP, Brazil.,Disciplina de Genética, Departamento de Morfologia e Genética, UNIFESP, São Paulo, SP, Brazil
| | - Marcos L Santoro
- Laboratório Interdisciplinar de Neurociências Clínicas (LiNC), Universidade Federal de São Paulo (UNIFESP), São Paulo, SP, Brazil.,Disciplina de Genética, Departamento de Morfologia e Genética, UNIFESP, São Paulo, SP, Brazil
| | - Ary Gadelha
- Laboratório Interdisciplinar de Neurociências Clínicas (LiNC), Universidade Federal de São Paulo (UNIFESP), São Paulo, SP, Brazil.,Programa de Esquizofrenia (PROESQ), Departamento de Psiquiatria, UNIFESP, São Paulo, SP, Brazil
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5
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Excess Glutamate May Cause Dilation of Retinal Blood Vessels in Glutamate/Aspartate Transporter-Deficient Mice. BIOMED RESEARCH INTERNATIONAL 2019; 2019:6512195. [PMID: 31828115 PMCID: PMC6881573 DOI: 10.1155/2019/6512195] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/11/2019] [Accepted: 10/22/2019] [Indexed: 11/18/2022]
Abstract
Purpose To investigate the longitudinal findings of fundus features and spectral-domain optical coherence tomography (SD-OCT) to characterize the morphologic features in a mouse model of defective glutamate/aspartate transporter (GLAST−/− mice). Materials and Methods The fundus findings and SD-OCT images were longitudinally recorded at five time points from postnatal (P) 22 to P156 in GLAST−/− mice. As a control wild type, age-matched C57BL/6J mice were employed. The mouse retina was subdivided into five layers, and the thickness of each layer was longitudinally measured by InSight® using SD-OCT pictures. The SD-OCT findings were compared with the histologic appearances. The diameter of the retinal blood vessels was measured by the ImageJ® software program using SD-OCT images. The data were statistically compared between both age-matched mouse groups. Results The retinal blood vessels appeared more dilated in GLAST−/− mice than in wild-type mice. This tendency was statistically significant at all time points after P44 by analyses using SD-OCT images. The ganglion cell complex (GCC) and outer nuclear layer (ONL) were significantly thinner in GLAST−/− mice at all time points after P80 than in the wild-type mice. This tendency was more clearly indicated by SD-OCT than histologic sections. Discussion In the present study, we found for the first time the dilation of the retinal blood vessels and the thinning of the ONL in GLAST−/− mice, in addition to the thinning of the GCC.
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Abstract
Schizophrenia (SZ) is a severe psychotic disorder that is highly heritable and common in the general population. The genetic heterogeneity of SZ is substantial, with contributions from common, rare, and de novo variants, in addition to environmental factors. Large genome-wide association studies have detected many variants that are associated with SZ, yet the pathways by which these variants influence risk remain largely unknown. SZ is also clinically heterogeneous, with patients exhibiting a broad range of deficits and symptom severity that vary over the course of illness and treatment, which has complicated efforts to identify risk variants. However, the underlying brain dysfunction forms a more stable trait marker that quantitative neurocognitive and neurophysiological endophenotypes may be able to objectively measure. These endophenotypes are less likely to be heterogeneous than the disorder and provide a neurobiological context to detect risk variants and underlying pathways among genes associated with SZ diagnosis. Furthermore, many endophenotypes are translational into animal model systems, allowing for direct evaluation of the neural circuit dysfunctions and neurobiological substrates. We review a selection of the most promising SZ endophenotypes, including prepulse inhibition, mismatch negativity, oculomotor antisaccade, letter-number sequencing, and continuous performance tests. We also highlight recent findings from large consortia that suggest the potential role of genes, particularly in the neuregulin and glutamate pathways, in several of these endophenotypes. Although endophenotypes require additional time and effort to assess, the insight into the underlying neurobiology that they provide may ultimately reveal the underlying genetic architecture for SZ and suggest novel treatment targets.
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7
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Magri C, Giacopuzzi E, La Via L, Bonini D, Ravasio V, Elhussiny MEA, Orizio F, Gangemi F, Valsecchi P, Bresciani R, Barbon A, Vita A, Gennarelli M. A novel homozygous mutation in GAD1 gene described in a schizophrenic patient impairs activity and dimerization of GAD67 enzyme. Sci Rep 2018; 8:15470. [PMID: 30341396 PMCID: PMC6195539 DOI: 10.1038/s41598-018-33924-8] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2018] [Accepted: 10/08/2018] [Indexed: 12/30/2022] Open
Abstract
Recently, by whole exome sequencing of schizophrenia (SCZ) patients, we identified a subject that was homozygous for a novel missense substitution (c.391 A > G) in the glutamate acid decarboxylase 1 (GAD1) gene. GAD1 encodes for GAD67 enzyme, catalyzing the production of gamma-aminobutyric acid (GABA) from L-glutamic acid. Here, we studied the impact of this mutation on GAD67 activity, dimerization and subcellular localization. Biochemical assay revealed that c.391 A > G reduces GAD67 enzymatic activity by ~30%, probably due to the impaired homodimerization of homozygous mutants as highlighted by proximity ligation assays. The mutational screening of 120 genes of the "GABAergic system" in a cohort of 4,225 SCZ cases and 5,834 controls (dbGaP: phs000473.v1.p2), did not identify other cases that were homozygous for ultra-rare variants in GAD1, but highlighted an increased frequency of cases that were homozygous for rare variants in genes of the GABA system (SCZ: 0.14% vs. Controls: 0.00%; p-value = 0.0055). In conclusion, this study demonstrates the functional impact of c.391 A > G variant and its biological effect makes it a good candidate as risk variant for SCZ. This study also supports an involvement of ultra-rare variants in GABAergic genes in the etiopathogenesis of SCZ.
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Affiliation(s)
- Chiara Magri
- Unit of Biology and Genetics, Department of Molecular and Translational Medicine, University of Brescia, Brescia, Italy.
| | - Edoardo Giacopuzzi
- Unit of Biology and Genetics, Department of Molecular and Translational Medicine, University of Brescia, Brescia, Italy
| | - Luca La Via
- Unit of Biology and Genetics, Department of Molecular and Translational Medicine, University of Brescia, Brescia, Italy
| | - Daniela Bonini
- Unit of Biology and Genetics, Department of Molecular and Translational Medicine, University of Brescia, Brescia, Italy
| | - Viola Ravasio
- Unit of Biology and Genetics, Department of Molecular and Translational Medicine, University of Brescia, Brescia, Italy
| | - Mohammed E A Elhussiny
- Unit of Biology and Genetics, Department of Molecular and Translational Medicine, University of Brescia, Brescia, Italy
| | - Flavia Orizio
- Unit of Biotechnology, Department of Molecular and Translational Medicine, University of Brescia, Brescia, Italy
| | - Fabrizio Gangemi
- Unit of Physics, Department of Molecular and Translational Medicine, University of Brescia, Brescia, Italy
| | - Paolo Valsecchi
- Neuroscience Section, Department of Clinical and Experimental Sciences, University of Brescia, Brescia, Italy
- Department of Mental Health, Spedali Civili Hospital, Brescia, Italy
| | - Roberto Bresciani
- Unit of Biotechnology, Department of Molecular and Translational Medicine, University of Brescia, Brescia, Italy
| | - Alessandro Barbon
- Unit of Biology and Genetics, Department of Molecular and Translational Medicine, University of Brescia, Brescia, Italy
| | - Antonio Vita
- Neuroscience Section, Department of Clinical and Experimental Sciences, University of Brescia, Brescia, Italy
- Department of Mental Health, Spedali Civili Hospital, Brescia, Italy
| | - Massimo Gennarelli
- Unit of Biology and Genetics, Department of Molecular and Translational Medicine, University of Brescia, Brescia, Italy
- Genetic Unit, IRCCS Centro S. Giovanni di Dio Fatebenefratelli, Brescia, Italy
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8
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Rodríguez-López J, Sobrino B, Amigo J, Carrera N, Brenlla J, Agra S, Paz E, Carracedo Á, Páramo M, Arrojo M, Costas J. Identification of putative second genetic hits in schizophrenia carriers of high-risk copy number variants and resequencing in additional samples. Eur Arch Psychiatry Clin Neurosci 2018; 268:585-592. [PMID: 28421333 DOI: 10.1007/s00406-017-0799-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/31/2016] [Accepted: 04/11/2017] [Indexed: 12/27/2022]
Abstract
Copy number variants (CNVs) conferring risk of schizophrenia present incomplete penetrance, suggesting the existence of second genetic hits. Identification of second hits may help to find genes with rare variants of susceptibility to schizophrenia. The aim of this work was to search for second hits of moderate/high risk in schizophrenia carriers of risk CNVs and resequencing of the relevant genes in additional samples. To this end, ten patients with risk CNVs at cytobands 15q11.2, 15q11.2-13.1, 16p11.2, or 16p13.11, were subjected to whole-exome sequencing. Rare single nucleotide variants, defined as those absent from main public databases, were classified according to bioinformatic prediction of pathogenicity by CADD scores. The average number of rare predicted pathogenic variants per sample was 13.6 (SD 2.01). Two genes, BFAR and SYNJ1, presented rare predicted pathogenic variants in more than one sample. Follow-up resequencing of these genes in 432 additional cases and 432 controls identified a significant excess of rare predicted pathogenic variants in case samples at SYNJ1. Taking into account its function in clathrin-mediated synaptic vesicle endocytosis at presynaptic terminals, our results suggest an impairment of this process in schizophrenia.
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Affiliation(s)
- Julio Rodríguez-López
- Instituto de Investigación Sanitaria (IDIS) de Santiago de Compostela, Complexo Hospitalario Universitario de Santiago de Compostela (CHUS), Servizo Galego de Saúde (SERGAS), Santiago de Compostela, Spain
| | - Beatriz Sobrino
- Instituto de Investigación Sanitaria (IDIS) de Santiago de Compostela, Complexo Hospitalario Universitario de Santiago de Compostela (CHUS), Servizo Galego de Saúde (SERGAS), Santiago de Compostela, Spain
- Grupo de Medicina Xenómica, Universidade de Santiago de Compostela (USC), Santiago de Compostela, Spain
- Fundación Pública Galega de Medicina Xenómica, Complexo Hospitalario Universitario de Santiago (CHUS), Servizo Galego de Saúde (SERGAS), Santiago de Compostela, Spain
| | - Jorge Amigo
- Instituto de Investigación Sanitaria (IDIS) de Santiago de Compostela, Complexo Hospitalario Universitario de Santiago de Compostela (CHUS), Servizo Galego de Saúde (SERGAS), Santiago de Compostela, Spain
- Grupo de Medicina Xenómica, Universidade de Santiago de Compostela (USC), Santiago de Compostela, Spain
- Fundación Pública Galega de Medicina Xenómica, Complexo Hospitalario Universitario de Santiago (CHUS), Servizo Galego de Saúde (SERGAS), Santiago de Compostela, Spain
| | - Noa Carrera
- Instituto de Investigación Sanitaria (IDIS) de Santiago de Compostela, Complexo Hospitalario Universitario de Santiago de Compostela (CHUS), Servizo Galego de Saúde (SERGAS), Santiago de Compostela, Spain
- Fundación Pública Galega de Medicina Xenómica, Complexo Hospitalario Universitario de Santiago (CHUS), Servizo Galego de Saúde (SERGAS), Santiago de Compostela, Spain
- Centre for Neuropsychiatric Genetics and Genomics, Institute of Psychological Medicine and Clinical Neurosciences, Cardiff University, Cardiff, UK
| | - Julio Brenlla
- Instituto de Investigación Sanitaria (IDIS) de Santiago de Compostela, Complexo Hospitalario Universitario de Santiago de Compostela (CHUS), Servizo Galego de Saúde (SERGAS), Santiago de Compostela, Spain
- Servizo de Psiquiatría, Complexo Hospitalario Universitario de Santiago de Compostela, Servizo Galego de Saúde (SERGAS), Santiago de Compostela, Spain
| | - Santiago Agra
- Instituto de Investigación Sanitaria (IDIS) de Santiago de Compostela, Complexo Hospitalario Universitario de Santiago de Compostela (CHUS), Servizo Galego de Saúde (SERGAS), Santiago de Compostela, Spain
- Servizo de Psiquiatría, Complexo Hospitalario Universitario de Santiago de Compostela, Servizo Galego de Saúde (SERGAS), Santiago de Compostela, Spain
| | - Eduardo Paz
- Instituto de Investigación Sanitaria (IDIS) de Santiago de Compostela, Complexo Hospitalario Universitario de Santiago de Compostela (CHUS), Servizo Galego de Saúde (SERGAS), Santiago de Compostela, Spain
- Servizo de Psiquiatría, Complexo Hospitalario Universitario de Santiago de Compostela, Servizo Galego de Saúde (SERGAS), Santiago de Compostela, Spain
| | - Ángel Carracedo
- Instituto de Investigación Sanitaria (IDIS) de Santiago de Compostela, Complexo Hospitalario Universitario de Santiago de Compostela (CHUS), Servizo Galego de Saúde (SERGAS), Santiago de Compostela, Spain
- Grupo de Medicina Xenómica, Universidade de Santiago de Compostela (USC), Santiago de Compostela, Spain
- Fundación Pública Galega de Medicina Xenómica, Complexo Hospitalario Universitario de Santiago (CHUS), Servizo Galego de Saúde (SERGAS), Santiago de Compostela, Spain
| | - Mario Páramo
- Instituto de Investigación Sanitaria (IDIS) de Santiago de Compostela, Complexo Hospitalario Universitario de Santiago de Compostela (CHUS), Servizo Galego de Saúde (SERGAS), Santiago de Compostela, Spain
- Servizo de Psiquiatría, Complexo Hospitalario Universitario de Santiago de Compostela, Servizo Galego de Saúde (SERGAS), Santiago de Compostela, Spain
| | - Manuel Arrojo
- Instituto de Investigación Sanitaria (IDIS) de Santiago de Compostela, Complexo Hospitalario Universitario de Santiago de Compostela (CHUS), Servizo Galego de Saúde (SERGAS), Santiago de Compostela, Spain
- Servizo de Psiquiatría, Complexo Hospitalario Universitario de Santiago de Compostela, Servizo Galego de Saúde (SERGAS), Santiago de Compostela, Spain
| | - Javier Costas
- Instituto de Investigación Sanitaria (IDIS) de Santiago de Compostela, Complexo Hospitalario Universitario de Santiago de Compostela (CHUS), Servizo Galego de Saúde (SERGAS), Santiago de Compostela, Spain.
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9
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Identification of genes carrying rare variants of moderate to large effect in schizophrenia: A replication study. Schizophr Res 2018; 197:577-578. [PMID: 29174335 DOI: 10.1016/j.schres.2017.11.021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/13/2017] [Revised: 11/17/2017] [Accepted: 11/18/2017] [Indexed: 11/23/2022]
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10
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Avramopoulos D. Recent Advances in the Genetics of Schizophrenia. MOLECULAR NEUROPSYCHIATRY 2018; 4:35-51. [PMID: 29998117 PMCID: PMC6032037 DOI: 10.1159/000488679] [Citation(s) in RCA: 65] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/07/2017] [Accepted: 03/21/2018] [Indexed: 12/27/2022]
Abstract
The last decade brought tremendous progress in the field of schizophrenia genetics. As a result of extensive collaborations and multiple technological advances, we now recognize many types of genetic variants that increase the risk. These include large copy number variants, rare coding inherited and de novο variants, and over 100 loci harboring common risk variants. While the type and contribution to the risk vary among genetic variants, there is concordance in the functions of genes they implicate, such as those whose RNA binds the fragile X-related protein FMRP and members of the activity-regulated cytoskeletal complex involved in learning and memory. Gene expression studies add important information on the biology of the disease and recapitulate the same functional gene groups. Studies of alternative phenotypes help us widen our understanding of the genetic architecture of mental function and dysfunction, how diseases overlap not only with each other but also with non-disease phenotypes. The challenge is to apply this new knowledge to prevention and treatment and help patients. The data generated so far and emerging technologies, including new methods in cell engineering, offer significant promise that in the next decade we will unlock the translational potential of these significant discoveries.
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Affiliation(s)
- Dimitrios Avramopoulos
- Institute of Genetic Medicine, Johns Hopkins University, Baltimore, Maryland, USA
- Department of Psychiatry, Johns Hopkins University, Baltimore, Maryland, USA
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11
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Exome array analysis suggests an increased variant burden in families with schizophrenia. Schizophr Res 2017; 185:9-16. [PMID: 27939555 DOI: 10.1016/j.schres.2016.12.007] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/17/2016] [Revised: 12/02/2016] [Accepted: 12/05/2016] [Indexed: 01/30/2023]
Abstract
The exome array assays rare-but-recurrent, likely deleterious, exonic variants and represents an intermediary between single nucleotide polymorphism (SNP) arrays and sequencing for genetic association studies. Multiplex families with multiple affected individuals may be enriched for disease-associated variants of this class compared to unrelated populations. We present an exome array study of schizophrenia in 99 multiplex families (n=341, including 118 cases) from the Western Australian Family Study of Schizophrenia (WAFSS). Compared to 55,726 individuals from the DIAGRAM sample not selected for schizophrenia, overall allele frequency of exome variants was higher in the WAFSS (P<2.2E-16). This was pronounced in variants nominally associated (P<0.05) with schizophrenia. Genes harbouring variants present only in WAFSS cases were enriched (FDR-corrected P=0.05) for membership of the 'extracellular matrix (ECM) - receptor interaction' biological pathway, adding to evidence that processes affecting the composition or turnover of ECM may contribute to neuropsychiatric disease. We did not find individual variants significantly associated with schizophrenia, although like previous studies, power to detect associations of small effect size was low. Cases did not exhibit a higher burden of variants compared to their unaffected relatives and the finding of previous exome chip studies of unrelated samples that 'schizophrenia gene-sets' were enriched for case-only variants was not replicated in the WAFSS. The higher frequency of moderately rare, exonic variants in these multiplex families compared to a population-based sample may account for some of their genetic liability to schizophrenia, and adds to evidence for a role of exome array variants from previous studies of unrelated samples.
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12
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Tang J, Fan Y, Li H, Xiang Q, Zhang DF, Li Z, He Y, Liao Y, Wang Y, He F, Zhang F, Shugart YY, Liu C, Tang Y, Chan RCK, Wang CY, Yao YG, Chen X. Whole-genome sequencing of monozygotic twins discordant for schizophrenia indicates multiple genetic risk factors for schizophrenia. J Genet Genomics 2017. [PMID: 28645778 DOI: 10.1016/j.jgg.2017.05.005] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Schizophrenia is a common disorder with a high heritability, but its genetic architecture is still elusive. We implemented whole-genome sequencing (WGS) analysis of 8 families with monozygotic (MZ) twin pairs discordant for schizophrenia to assess potential association of de novo mutations (DNMs) or inherited variants with susceptibility to schizophrenia. Eight non-synonymous DNMs (including one splicing site) were identified and shared by twins, which were either located in previously reported schizophrenia risk genes (p.V24689I mutation in TTN, p.S2506T mutation in GCN1L1, IVS3+1G > T in DOCK1) or had a benign to damaging effect according to in silico prediction analysis. By searching the inherited rare damaging or loss-of-function (LOF) variants and common susceptible alleles from three classes of schizophrenia candidate genes, we were able to distill genetic alterations in several schizophrenia risk genes, including GAD1, PLXNA2, RELN and FEZ1. Four inherited copy number variations (CNVs; including a large deletion at 16p13.11) implicated for schizophrenia were identified in four families, respectively. Most of families carried both missense DNMs and inherited risk variants, which might suggest that DNMs, inherited rare damaging variants and common risk alleles together conferred to schizophrenia susceptibility. Our results support that schizophrenia is caused by a combination of multiple genetic factors, with each DNM/variant showing a relatively small effect size.
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Affiliation(s)
- Jinsong Tang
- Institute of Mental Health, National Clinical Research Center for Mental Health Disorders and National Technology Institute of Psychiatry, and Key Laboratory of Psychiatry and Mental Health of Hunan Province, The Second Xiangya Hospital, Central South University, Changsha 410011, China
| | - Yu Fan
- Key Laboratory of Animal Models and Human Disease Mechanisms of the Chinese Academy of Sciences & Yunnan Province, Kunming Institute of Zoology, Kunming 650223, China
| | - Hong Li
- Institute of Mental Health, National Clinical Research Center for Mental Health Disorders and National Technology Institute of Psychiatry, and Key Laboratory of Psychiatry and Mental Health of Hunan Province, The Second Xiangya Hospital, Central South University, Changsha 410011, China; Department of Psychiatry, The First Affiliated Hospital of Zhengzhou University, Zhengzhou 450052, China
| | - Qun Xiang
- Key Laboratory of Animal Models and Human Disease Mechanisms of the Chinese Academy of Sciences & Yunnan Province, Kunming Institute of Zoology, Kunming 650223, China; Kunming College of Life Science, University of Chinese Academy of Sciences, Kunming 650204, China
| | - Deng-Feng Zhang
- Key Laboratory of Animal Models and Human Disease Mechanisms of the Chinese Academy of Sciences & Yunnan Province, Kunming Institute of Zoology, Kunming 650223, China
| | - Zongchang Li
- Institute of Mental Health, National Clinical Research Center for Mental Health Disorders and National Technology Institute of Psychiatry, and Key Laboratory of Psychiatry and Mental Health of Hunan Province, The Second Xiangya Hospital, Central South University, Changsha 410011, China
| | - Ying He
- Institute of Mental Health, National Clinical Research Center for Mental Health Disorders and National Technology Institute of Psychiatry, and Key Laboratory of Psychiatry and Mental Health of Hunan Province, The Second Xiangya Hospital, Central South University, Changsha 410011, China
| | - Yanhui Liao
- Institute of Mental Health, National Clinical Research Center for Mental Health Disorders and National Technology Institute of Psychiatry, and Key Laboratory of Psychiatry and Mental Health of Hunan Province, The Second Xiangya Hospital, Central South University, Changsha 410011, China
| | - Ya Wang
- Neuropsychology and Applied Cognitive Neuroscience Laboratory, and CAS Key Laboratory of Mental Health, Institute of Psychology, Chinese Academy of Sciences, Beijing 100101, China
| | - Fan He
- Beijing Key Laboratory of Mental Disorders, Department of Psychiatry, Beijing Anding Hospital, and Center of Schizophrenia, Beijing Institute for Brain Disorders and Laboratory of Brain Disorders of the Ministry of Science and Technology, Capital Medical University, Beijing 100088, China
| | - Fengyu Zhang
- Institute of Mental Health, National Clinical Research Center for Mental Health Disorders and National Technology Institute of Psychiatry, and Key Laboratory of Psychiatry and Mental Health of Hunan Province, The Second Xiangya Hospital, Central South University, Changsha 410011, China
| | - Yin Yao Shugart
- Unit on Statistical Genomics, Intramural Research Programs, National Institute of Mental Health, NIH, Bethesda 20892, USA
| | - Chunyu Liu
- Institute of Human Genetics, University of Illinois at Chicago, Chicago, IL 60607, USA
| | - Yanqing Tang
- Department of Psychiatry, The First Affiliated Hospital of China Medical University, Shenyang 110122, China.
| | - Raymond C K Chan
- Neuropsychology and Applied Cognitive Neuroscience Laboratory, and CAS Key Laboratory of Mental Health, Institute of Psychology, Chinese Academy of Sciences, Beijing 100101, China.
| | - Chuan-Yue Wang
- Beijing Key Laboratory of Mental Disorders, Department of Psychiatry, Beijing Anding Hospital, and Center of Schizophrenia, Beijing Institute for Brain Disorders and Laboratory of Brain Disorders of the Ministry of Science and Technology, Capital Medical University, Beijing 100088, China.
| | - Yong-Gang Yao
- Key Laboratory of Animal Models and Human Disease Mechanisms of the Chinese Academy of Sciences & Yunnan Province, Kunming Institute of Zoology, Kunming 650223, China; Kunming College of Life Science, University of Chinese Academy of Sciences, Kunming 650204, China; CAS Center for Excellence in Brain Science and Intelligence Technology, Chinese Academy of Sciences, Shanghai 200031, China.
| | - Xiaogang Chen
- Institute of Mental Health, National Clinical Research Center for Mental Health Disorders and National Technology Institute of Psychiatry, and Key Laboratory of Psychiatry and Mental Health of Hunan Province, The Second Xiangya Hospital, Central South University, Changsha 410011, China.
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13
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Krystal JH, Anticevic A, Yang GJ, Dragoi G, Driesen NR, Wang XJ, Murray JD. Impaired Tuning of Neural Ensembles and the Pathophysiology of Schizophrenia: A Translational and Computational Neuroscience Perspective. Biol Psychiatry 2017; 81:874-885. [PMID: 28434616 PMCID: PMC5407407 DOI: 10.1016/j.biopsych.2017.01.004] [Citation(s) in RCA: 138] [Impact Index Per Article: 19.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/13/2016] [Revised: 12/14/2016] [Accepted: 01/04/2017] [Indexed: 10/20/2022]
Abstract
The functional optimization of neural ensembles is central to human higher cognitive functions. When the functions through which neural activity is tuned fail to develop or break down, symptoms and cognitive impairments arise. This review considers ways in which disturbances in the balance of excitation and inhibition might develop and be expressed in cortical networks in association with schizophrenia. This presentation is framed within a developmental perspective that begins with disturbances in glutamate synaptic development in utero. It considers developmental correlates and consequences, including compensatory mechanisms that increase intrinsic excitability or reduce inhibitory tone. It also considers the possibility that these homeostatic increases in excitability have potential negative functional and structural consequences. These negative functional consequences of disinhibition may include reduced working memory-related cortical activity associated with the downslope of the "inverted-U" input-output curve, impaired spatial tuning of neural activity and impaired sparse coding of information, and deficits in the temporal tuning of neural activity and its implication for neural codes. The review concludes by considering the functional significance of noisy activity for neural network function. The presentation draws on computational neuroscience and pharmacologic and genetic studies in animals and humans, particularly those involving N-methyl-D-aspartate glutamate receptor antagonists, to illustrate principles of network regulation that give rise to features of neural dysfunction associated with schizophrenia. While this presentation focuses on schizophrenia, the general principles outlined in the review may have broad implications for considering disturbances in the regulation of neural ensembles in psychiatric disorders.
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Affiliation(s)
- John H. Krystal
- Department of Psychiatry, Yale University School of Medicine, New Haven, CT USA,Department of Neuroscience, Yale University School of Medicine, New Haven, CT USA,Clinical Neuroscience Division, VA National Center for PTSD, VA Connecticut Healthcare System, West Haven, CT USA,Behavioral Health Services, Yale-New Haven Hospital, New Haven, CT USA
| | - Alan Anticevic
- Department of Psychiatry, Yale University School of Medicine, New Haven, CT USA,Department of Psychology, Yale University
| | - Genevieve J. Yang
- Department of Psychiatry, Yale University School of Medicine, New Haven, CT USA,Department of Neuroscience, Yale University School of Medicine, New Haven, CT USA
| | - George Dragoi
- Department of Psychiatry, Yale University School of Medicine, New Haven, CT USA,Department of Neuroscience, Yale University School of Medicine, New Haven, CT USA
| | - Naomi R. Driesen
- Department of Psychiatry, Yale University School of Medicine, New Haven, CT USA,Clinical Neuroscience Division, VA National Center for PTSD, VA Connecticut Healthcare System, West Haven, CT USA
| | | | - John D. Murray
- Department of Psychiatry, Yale University School of Medicine, New Haven, CT USA
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14
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Functional analysis of rare variants found in schizophrenia implicates a critical role for GIT1-PAK3 signaling in neuroplasticity. Mol Psychiatry 2017; 22:417-429. [PMID: 27457813 PMCID: PMC6186433 DOI: 10.1038/mp.2016.98] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/27/2016] [Revised: 03/21/2016] [Accepted: 05/02/2016] [Indexed: 01/21/2023]
Abstract
Although the pathogenesis of schizophrenia (SCZ) is proposed to involve alterations of neural circuits via synaptic dysfunction, the underlying molecular mechanisms remain poorly understood. Recent exome sequencing studies of SCZ have uncovered numerous single-nucleotide variants (SNVs); however, the majority of these SNVs have unknown functional consequences, leaving their disease relevance uncertain. Filling this knowledge gap requires systematic application of quantitative and scalable assays to assess known and novel biological functions of genes. Here we demonstrate loss-of-function effects of multiple rare coding SNVs found in SCZ subjects in the GIT1 (G protein-coupled receptor kinase interacting ArfGAP 1) gene using functional cell-based assays involving coexpression of GIT1 and PAK3 (p21 protein (Cdc42/Rac)-activated kinase 3). Most notably, a GIT1-R283W variant reported in four independent SCZ cases was defective in activating PAK3 as well as MAPK (mitogen-activated protein kinase). Similar functional deficits were found for a de novo SCZ variant GIT1-S601N. Additional assays revealed deficits in the capacity of GIT1-R283W to stimulate PAK phosphorylation in cultured hippocampal neurons. In addition, GIT1-R283W showed deficits in the induction of GAD1 (glutamate decarboxylase 1) protein expression. Extending these functional assays to 10 additional rare GIT1 variants revealed the existence of an allelic series with the majority of the SCZ case variants exhibiting loss of function toward MAPK activation in a manner correlated with loss of PAK3 activation. Taken together, we propose that rare variants in GIT1, along with other genetic and environmental factors, cause dysregulation of PAK3 leading to synaptic deficits in SCZ.
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15
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Alural B, Genc S, Haggarty SJ. Diagnostic and therapeutic potential of microRNAs in neuropsychiatric disorders: Past, present, and future. Prog Neuropsychopharmacol Biol Psychiatry 2017; 73:87-103. [PMID: 27072377 PMCID: PMC5292013 DOI: 10.1016/j.pnpbp.2016.03.010] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/04/2016] [Revised: 03/28/2016] [Accepted: 03/30/2016] [Indexed: 12/12/2022]
Abstract
Neuropsychiatric disorders are common health problems affecting approximately 1% of the population. Twin, adoption, and family studies have displayed a strong genetic component for many of these disorders; however, the underlying pathophysiological mechanisms and neural substrates remain largely unknown. Given the critical need for new diagnostic markers and disease-modifying treatments, expanding the focus of genomic studies of neuropsychiatric disorders to include the role of non-coding RNAs (ncRNAs) is of growing interest. Of known types of ncRNAs, microRNAs (miRNAs) are 20-25-nucleotide, single-stranded, molecules that regulate gene expression through post-transcriptional mechanisms and have the potential to coordinately regulate complex regulatory networks. In this review, we summarize the current knowledge on miRNA alteration/dysregulation in neuropsychiatric disorders, with a special emphasis on schizophrenia (SCZ), bipolar disorder (BD), and major depressive disorder (MDD). With an eye toward the future, we also discuss the diagnostic and prognostic potential of miRNAs for neuropsychiatric disorders in the context of personalized treatments and network medicine.
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Affiliation(s)
- Begum Alural
- Department of Neuroscience, Faculty of Medicine, Dokuz Eylul University, Izmir, Turkey; Izmir Biomedicine and Genome Center, Dokuz Eylul University, Izmir, Turkey
| | - Sermin Genc
- Department of Neuroscience, Faculty of Medicine, Dokuz Eylul University, Izmir, Turkey; Izmir Biomedicine and Genome Center, Dokuz Eylul University, Izmir, Turkey
| | - Stephen J Haggarty
- Center for Human Genetic Research, Massachusetts General Hospital, Boston, MA 02114, USA; Chemical Neurobiology Laboratory, Departments of Neurology and Psychiatry, Massachusetts General Hospital, Harvard Medical School, Boston, MA 02114, USA.
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16
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Hou L, Sun N, Mane S, Sayward F, Rajeevan N, Cheung KH, Cho K, Pyarajan S, Aslan M, Miller P, Harvey PD, Gaziano JM, Concato J, Zhao H. Impact of genotyping errors on statistical power of association tests in genomic analyses: A case study. Genet Epidemiol 2016; 41:152-162. [PMID: 28019059 DOI: 10.1002/gepi.22027] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2016] [Revised: 08/15/2016] [Accepted: 10/10/2016] [Indexed: 12/13/2022]
Abstract
A key step in genomic studies is to assess high throughput measurements across millions of markers for each participant's DNA, either using microarrays or sequencing techniques. Accurate genotype calling is essential for downstream statistical analysis of genotype-phenotype associations, and next generation sequencing (NGS) has recently become a more common approach in genomic studies. How the accuracy of variant calling in NGS-based studies affects downstream association analysis has not, however, been studied using empirical data in which both microarrays and NGS were available. In this article, we investigate the impact of variant calling errors on the statistical power to identify associations between single nucleotides and disease, and on associations between multiple rare variants and disease. Both differential and nondifferential genotyping errors are considered. Our results show that the power of burden tests for rare variants is strongly influenced by the specificity in variant calling, but is rather robust with regard to sensitivity. By using the variant calling accuracies estimated from a substudy of a Cooperative Studies Program project conducted by the Department of Veterans Affairs, we show that the power of association tests is mostly retained with commonly adopted variant calling pipelines. An R package, GWAS.PC, is provided to accommodate power analysis that takes account of genotyping errors (http://zhaocenter.org/software/).
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Affiliation(s)
- Lin Hou
- Clinical Epidemiology Research Center (CERC), Veterans Affairs (VA) Cooperative Studies Program, VA Connecticut Healthcare System, West Haven, Connecticut, United States of America.,Department of Biostatistics, Yale School of Public Health, New Haven, Connecticut, United States of America
| | - Ning Sun
- Clinical Epidemiology Research Center (CERC), Veterans Affairs (VA) Cooperative Studies Program, VA Connecticut Healthcare System, West Haven, Connecticut, United States of America.,Department of Biostatistics, Yale School of Public Health, New Haven, Connecticut, United States of America
| | - Shrikant Mane
- Department of Genetics, Yale University School of Medicine, New Haven, Connecticut, United States of America
| | - Fred Sayward
- Clinical Epidemiology Research Center (CERC), Veterans Affairs (VA) Cooperative Studies Program, VA Connecticut Healthcare System, West Haven, Connecticut, United States of America.,Center for Medical Informatics, Yale University School of Medicine, New Haven, Connecticut, United States of America
| | - Nallakkandi Rajeevan
- Clinical Epidemiology Research Center (CERC), Veterans Affairs (VA) Cooperative Studies Program, VA Connecticut Healthcare System, West Haven, Connecticut, United States of America.,Center for Medical Informatics, Yale University School of Medicine, New Haven, Connecticut, United States of America
| | - Kei-Hoi Cheung
- Clinical Epidemiology Research Center (CERC), Veterans Affairs (VA) Cooperative Studies Program, VA Connecticut Healthcare System, West Haven, Connecticut, United States of America.,Center for Medical Informatics, Yale University School of Medicine, New Haven, Connecticut, United States of America
| | - Kelly Cho
- Massachusetts Area Veterans Epidemiology Research and Information Center (MAVERIC), VA Cooperative Studies Program, VA Boston Healthcare System, Boston, Massachusetts, United States of America.,Department of Medicine, Harvard University School of Medicine, Boston, Massachusetts, United States of America
| | - Saiju Pyarajan
- Massachusetts Area Veterans Epidemiology Research and Information Center (MAVERIC), VA Cooperative Studies Program, VA Boston Healthcare System, Boston, Massachusetts, United States of America.,Department of Medicine, Harvard University School of Medicine, Boston, Massachusetts, United States of America
| | - Mihaela Aslan
- Clinical Epidemiology Research Center (CERC), Veterans Affairs (VA) Cooperative Studies Program, VA Connecticut Healthcare System, West Haven, Connecticut, United States of America.,Department of Medicine, Yale University School of Medicine, New Haven, Connecticut, United States of America
| | - Perry Miller
- Clinical Epidemiology Research Center (CERC), Veterans Affairs (VA) Cooperative Studies Program, VA Connecticut Healthcare System, West Haven, Connecticut, United States of America.,Center for Medical Informatics, Yale University School of Medicine, New Haven, Connecticut, United States of America
| | - Philip D Harvey
- Bruce W. Carter Miami Veterans Affairs (VA) Medical Center, Miami, Florida, United States of America.,Department of Psychiatry, University of Miami Miller School of Medicine, Miami, Florida, United States of America
| | - J Michael Gaziano
- Massachusetts Area Veterans Epidemiology Research and Information Center (MAVERIC), VA Cooperative Studies Program, VA Boston Healthcare System, Boston, Massachusetts, United States of America.,Department of Medicine, Harvard University School of Medicine, Boston, Massachusetts, United States of America
| | - John Concato
- Clinical Epidemiology Research Center (CERC), Veterans Affairs (VA) Cooperative Studies Program, VA Connecticut Healthcare System, West Haven, Connecticut, United States of America.,Department of Medicine, Yale University School of Medicine, New Haven, Connecticut, United States of America
| | - Hongyu Zhao
- Clinical Epidemiology Research Center (CERC), Veterans Affairs (VA) Cooperative Studies Program, VA Connecticut Healthcare System, West Haven, Connecticut, United States of America.,Department of Biostatistics, Yale School of Public Health, New Haven, Connecticut, United States of America
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17
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Hayashi-Takagi A. Synapse pathology and translational applications for schizophrenia. Neurosci Res 2016; 114:3-8. [PMID: 27633835 DOI: 10.1016/j.neures.2016.09.001] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2016] [Revised: 06/14/2016] [Accepted: 08/31/2016] [Indexed: 01/01/2023]
Abstract
Schizophrenia is a chronic, severe, and disabling brain disorder, with an estimated lifetime prevalence of 0.7%. Despite its relatively low prevalence, the onset of schizophrenia usually occurs early in life, resulting in a severe lifelong disability for patients and increasing the economic and care burden on their families. This makes schizophrenia one of the most catastrophic mental illnesses. Although the etiology of schizophrenia remains poorly understood, clinical, genetic, and pharmacological studies have indicated that its pathophysiology involves synaptic disturbances. Here, I review the evidence suggesting synaptic disturbance as the causal pathophysiology of schizophrenia and discuss the possible application of synaptic intervention as a novel therapeutic strategy for schizophrenia.
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Affiliation(s)
- Akiko Hayashi-Takagi
- Laboratory of Medical Neuroscience, Institute for Molecular and Cellular Regulation, Gunma University, Maebachi, Gunma 371-8512, Japan; PRESTO, Japan Science and Technology Agency, 4-1-8 Honcho, Kawaguchi, Saitama 332-0012, Japan.
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18
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González-Peñas J, Amigo J, Santomé L, Sobrino B, Brenlla J, Agra S, Paz E, Páramo M, Carracedo Á, Arrojo M, Costas J. Targeted resequencing of regulatory regions at schizophrenia risk loci: Role of rare functional variants at chromatin repressive states. Schizophr Res 2016; 174:10-16. [PMID: 27066855 DOI: 10.1016/j.schres.2016.03.029] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/24/2016] [Accepted: 03/24/2016] [Indexed: 12/30/2022]
Abstract
There is mounting evidence that regulatory variation plays an important role in genetic risk for schizophrenia. Here, we specifically search for regulatory variants at risk by sequencing promoter regions of twenty-three genes implied in schizophrenia by copy number variant or genome-wide association studies. After strict quality control, a total of 55,206bp per sample were analyzed in 526 schizophrenia cases and 516 controls from Galicia, NW Spain, using the Applied Biosystems SOLiD System. Variants were filtered based on frequency from public databases, chromatin states from the RoadMap Epigenomics Consortium at tissues relevant for schizophrenia, such as fetal brain, mid-frontal lobe, and angular gyrus, and prediction of functionality from RegulomeDB. The proportion of rare variants at polycomb repressive chromatin state at relevant tissues was higher in cases than in controls. The proportion of rare variants with predicted regulatory role was significantly higher in cases than in controls (P=0.0028, OR=1.93, 95% C.I.=1.23-3.04). Combination of information from both sources led to the identification of an excess of carriers of rare variants with predicted regulatory role located at polycomb repressive chromatin state at relevant tissues in cases versus controls (P=0.0016, OR=19.34, 95% C.I.=2.45-2495.26). The variants are located at two genes affected by the 17q12 copy number variant, LHX1 and HNF1B. These data strongly suggest that a specific epigenetic mechanism, chromatin remodeling by histone modification during early development, may be impaired in a subset of schizophrenia patients, in agreement with previous data.
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Affiliation(s)
- Javier González-Peñas
- Instituto de Investigación Sanitaria (IDIS) de Santiago de Compostela, Complexo Hospitalario Universitario de Santiago de Compostela (CHUS), Servizo Galego de Saúde (SERGAS), Santiago de Compostela, Spain
| | - Jorge Amigo
- Instituto de Investigación Sanitaria (IDIS) de Santiago de Compostela, Complexo Hospitalario Universitario de Santiago de Compostela (CHUS), Servizo Galego de Saúde (SERGAS), Santiago de Compostela, Spain; Grupo de Medicina Xenómica, Universidade de Santiago de Compostela (USC), Santiago de Compostela, Spain; Fundación Pública Galega de Medicina Xenómica, Complexo Hospitalario Universitario de Santiago (CHUS), Servizo Galego de Saúde (SERGAS), Santiago de Compostela, Spain
| | - Luis Santomé
- Fundación Pública Galega de Medicina Xenómica, Complexo Hospitalario Universitario de Santiago (CHUS), Servizo Galego de Saúde (SERGAS), Santiago de Compostela, Spain
| | - Beatriz Sobrino
- Instituto de Investigación Sanitaria (IDIS) de Santiago de Compostela, Complexo Hospitalario Universitario de Santiago de Compostela (CHUS), Servizo Galego de Saúde (SERGAS), Santiago de Compostela, Spain; Grupo de Medicina Xenómica, Universidade de Santiago de Compostela (USC), Santiago de Compostela, Spain; Fundación Pública Galega de Medicina Xenómica, Complexo Hospitalario Universitario de Santiago (CHUS), Servizo Galego de Saúde (SERGAS), Santiago de Compostela, Spain
| | - Julio Brenlla
- Instituto de Investigación Sanitaria (IDIS) de Santiago de Compostela, Complexo Hospitalario Universitario de Santiago de Compostela (CHUS), Servizo Galego de Saúde (SERGAS), Santiago de Compostela, Spain; Servizo de Psiquiatría, Complexo Hospitalario Universitario de Santiago de Compostela, Servizo Galego de Saúde (SERGAS), Santiago de Compostela, Spain
| | - Santiago Agra
- Instituto de Investigación Sanitaria (IDIS) de Santiago de Compostela, Complexo Hospitalario Universitario de Santiago de Compostela (CHUS), Servizo Galego de Saúde (SERGAS), Santiago de Compostela, Spain; Servizo de Psiquiatría, Complexo Hospitalario Universitario de Santiago de Compostela, Servizo Galego de Saúde (SERGAS), Santiago de Compostela, Spain
| | - Eduardo Paz
- Instituto de Investigación Sanitaria (IDIS) de Santiago de Compostela, Complexo Hospitalario Universitario de Santiago de Compostela (CHUS), Servizo Galego de Saúde (SERGAS), Santiago de Compostela, Spain; Servizo de Psiquiatría, Complexo Hospitalario Universitario de Santiago de Compostela, Servizo Galego de Saúde (SERGAS), Santiago de Compostela, Spain
| | - Mario Páramo
- Instituto de Investigación Sanitaria (IDIS) de Santiago de Compostela, Complexo Hospitalario Universitario de Santiago de Compostela (CHUS), Servizo Galego de Saúde (SERGAS), Santiago de Compostela, Spain; Servizo de Psiquiatría, Complexo Hospitalario Universitario de Santiago de Compostela, Servizo Galego de Saúde (SERGAS), Santiago de Compostela, Spain
| | - Ángel Carracedo
- Instituto de Investigación Sanitaria (IDIS) de Santiago de Compostela, Complexo Hospitalario Universitario de Santiago de Compostela (CHUS), Servizo Galego de Saúde (SERGAS), Santiago de Compostela, Spain; Grupo de Medicina Xenómica, Universidade de Santiago de Compostela (USC), Santiago de Compostela, Spain; Fundación Pública Galega de Medicina Xenómica, Complexo Hospitalario Universitario de Santiago (CHUS), Servizo Galego de Saúde (SERGAS), Santiago de Compostela, Spain
| | - Manuel Arrojo
- Instituto de Investigación Sanitaria (IDIS) de Santiago de Compostela, Complexo Hospitalario Universitario de Santiago de Compostela (CHUS), Servizo Galego de Saúde (SERGAS), Santiago de Compostela, Spain; Servizo de Psiquiatría, Complexo Hospitalario Universitario de Santiago de Compostela, Servizo Galego de Saúde (SERGAS), Santiago de Compostela, Spain
| | - Javier Costas
- Instituto de Investigación Sanitaria (IDIS) de Santiago de Compostela, Complexo Hospitalario Universitario de Santiago de Compostela (CHUS), Servizo Galego de Saúde (SERGAS), Santiago de Compostela, Spain.
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Schuch JB, Paixão-Côrtes VR, Friedrich DC, Tovo-Rodrigues L. The contribution of protein intrinsic disorder to understand the role of genetic variants uncovered by autism spectrum disorders exome studies. Am J Med Genet B Neuropsychiatr Genet 2016; 171B:479-91. [PMID: 26892727 DOI: 10.1002/ajmg.b.32431] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/24/2015] [Accepted: 02/04/2016] [Indexed: 01/09/2023]
Abstract
Several autism spectrum disorders (ASD) exome studies suggest that coding single nucleotide variants (SNVs) play an important role on ASD etiology. Usually, the pathogenic effect of missense mutations is estimated through predictors that lose accuracy for those SNVs placed in intrinsically disordered regions of protein. Here, we used bioinformatics tools to investigate the effect of mutations described in ASD published exome studies (549 mutations) in protein disorder, considering post-translational modification, PEST and Molecular Recognition Features (MoRFs) motifs. Schizophrenia and type 2 diabetes (T2D) datasets were created for comparison purposes. The frequency of mutations predicted as disordered was comparable among the three datasets (38.1% in ASD, 35.7% in schizophrenia, 46.4% in T2D). However, the frequency of SNVs predicted to lead a gain or loss of functional sites or change intrinsic disorder tendencies was higher in ASD and schizophrenia than T2D (46.9%, 36.4%, and 23.1%, respectively). The results obtained by SIFT and PolyPhen-2 indicated that 38.9% and 34.4% of the mutations predicted, respectively, as tolerated and benign showed functional alterations in disorder properties. Given the frequency of mutations placed in IDRs and their functional impact, this study suggests that alterations in intrinsic disorder properties might play a role in ASD and schizophrenia etiologies. They should be taken into consideration when researching the pathogenicity of mutations in neurodevelopmental and psychiatric diseases. Finally, mutations with functional alterations in disorder properties must be potential targets for in vitro and in vivo functional studies.
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Affiliation(s)
- Jaqueline Bohrer Schuch
- Department of Genetics, Federal University of Rio Grande do Sul (UFRGS), Porto Alegre, Rio Grande do Sul, Brazil
| | | | - Deise C Friedrich
- Department of Cellular and Molecular Biology, Pontifical Catholic University of Rio Grande do Sul (PUCRS), Porto Alegre, Rio Grande do Sul, Brazil
| | - Luciana Tovo-Rodrigues
- Postgraduate Program in Epidemiology, Federal University of Pelotas (UFPel), Pelotas, Rio Grande do Sul, Brazil
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20
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Maj C, Minelli A, Giacopuzzi E, Sacchetti E, Gennarelli M. The Role of Metabotropic Glutamate Receptor Genes in Schizophrenia. Curr Neuropharmacol 2016; 14:540-50. [PMID: 27296644 PMCID: PMC4983747 DOI: 10.2174/1570159x13666150514232745] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2015] [Revised: 04/04/2015] [Accepted: 05/12/2015] [Indexed: 11/22/2022] Open
Abstract
Genomic studies revealed two main components in the genetic architecture of schizophrenia, one constituted by common variants determining a distributed polygenic effect and one represented by a large number of heterogeneous rare and highly disruptive mutations. These gene modifications often affect neural transmission and different studies proved an involvement of metabotropic glutamate receptors in schizophrenia phenotype. Through the combination of literature information with genomic data from public repositories, we analyzed the current knowledge on the involvement of genetic variations of the human metabotropic glutamate receptors in schizophrenia and related endophenotypes. Despite the analysis did not reveal a definitive connection, different suggestive associations have been identified and in particular a relevant role has emerged for GRM3 in affecting specific schizophrenia endophenotypes. This supports the hypothesis that these receptors are directly involved in schizophrenia disorder.
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Affiliation(s)
| | | | | | | | - Massimo Gennarelli
- Department of Molecular and Translational Medicine, Biology and Genetic Division, University of Brescia, Viale Europa, 11 - 25123 Brescia, Italy.
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21
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Cancer classification in the genomic era: five contemporary problems. Hum Genomics 2015; 9:27. [PMID: 26481255 PMCID: PMC4612488 DOI: 10.1186/s40246-015-0049-8] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2015] [Accepted: 10/06/2015] [Indexed: 12/20/2022] Open
Abstract
Classification is an everyday instinct as well as a full-fledged scientific discipline. Throughout the history of medicine, disease classification is central to how we develop knowledge, make diagnosis, and assign treatment. Here, we discuss the classification of cancer and the process of categorizing cancer subtypes based on their observed clinical and biological features. Traditionally, cancer nomenclature is primarily based on organ location, e.g., “lung cancer” designates a tumor originating in lung structures. Within each organ-specific major type, finer subgroups can be defined based on patient age, cell type, histological grades, and sometimes molecular markers, e.g., hormonal receptor status in breast cancer or microsatellite instability in colorectal cancer. In the past 15+ years, high-throughput technologies have generated rich new data regarding somatic variations in DNA, RNA, protein, or epigenomic features for many cancers. These data, collected for increasingly large tumor cohorts, have provided not only new insights into the biological diversity of human cancers but also exciting opportunities to discover previously unrecognized cancer subtypes. Meanwhile, the unprecedented volume and complexity of these data pose significant challenges for biostatisticians, cancer biologists, and clinicians alike. Here, we review five related issues that represent contemporary problems in cancer taxonomy and interpretation. (1) How many cancer subtypes are there? (2) How can we evaluate the robustness of a new classification system? (3) How are classification systems affected by intratumor heterogeneity and tumor evolution? (4) How should we interpret cancer subtypes? (5) Can multiple classification systems co-exist? While related issues have existed for a long time, we will focus on those aspects that have been magnified by the recent influx of complex multi-omics data. Exploration of these problems is essential for data-driven refinement of cancer classification and the successful application of these concepts in precision medicine.
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22
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Genetic Architecture of Complex Human Traits: What Have We Learned from Genome-Wide Association Studies? CURRENT GENETIC MEDICINE REPORTS 2015. [DOI: 10.1007/s40142-015-0083-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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23
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Gu W, Gurguis CI, Zhou JJ, Zhu Y, Ko EA, Ko JH, Wang T, Zhou T. Functional and Structural Consequence of Rare Exonic Single Nucleotide Polymorphisms: One Story, Two Tales. Genome Biol Evol 2015; 7:2929-40. [PMID: 26454016 PMCID: PMC4684694 DOI: 10.1093/gbe/evv191] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/05/2015] [Indexed: 01/01/2023] Open
Abstract
Genetic variation arising from single nucleotide polymorphisms (SNPs) is ubiquitously found among human populations. While disease-causing variants are known in some cases, identifying functional or causative variants for most human diseases remains a challenging task. Rare SNPs, rather than common ones, are thought to be more important in the pathology of most human diseases. We propose that rare SNPs should be divided into two categories dependent on whether the minor alleles are derived or ancestral. Derived alleles are less likely to have been purified by evolutionary processes and may be more likely to induce deleterious effects. We therefore hypothesized that the rare SNPs with derived minor alleles would be more important for human diseases and predicted that these variants would have larger functional or structural consequences relative to the rare variants for which the minor alleles are ancestral. We systematically investigated the consequences of the exonic SNPs on protein function, mRNA structure, and translation. We found that the functional and structural consequences are more significant for the rare exonic variants for which the minor alleles are derived. However, this pattern is reversed when the minor alleles are ancestral. Thus, the rare exonic SNPs with derived minor alleles are more likely to be deleterious. Age estimation of rare SNPs confirms that these potentially deleterious SNPs are recently evolved in the human population. These results have important implications for understanding the function of genetic variations in human exonic regions and for prioritizing functional SNPs in genome-wide association studies of human diseases.
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Affiliation(s)
- Wanjun Gu
- Research Center for Learning Sciences, Southeast University, Nanjing, Jiangsu, China
| | | | - Jin J Zhou
- Department of Epidemiology and Biostatistics, The University of Arizona
| | - Yihua Zhu
- School of Biological Science and Medical Engineering, Southeast University, Nanjing, Jiangsu, China College of Information Science and Technology, Nanjing Agricultural University, Nanjing, Jiangsu, China
| | - Eun-A Ko
- Department of Pharmacology, The University of Nevada School of Medicine, Reno
| | - Jae-Hong Ko
- Department of Physiology, College of Medicine, Chung-Ang University, Seoul, South Korea
| | - Ting Wang
- Department of Medicine, The University of Arizona
| | - Tong Zhou
- Department of Medicine, The University of Arizona
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Whole-Genome Sequencing Suggests Schizophrenia Risk Mechanisms in Humans with 22q11.2 Deletion Syndrome. G3-GENES GENOMES GENETICS 2015; 5:2453-61. [PMID: 26384369 PMCID: PMC4632064 DOI: 10.1534/g3.115.021345] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Chromosome 22q11.2 microdeletions impart a high but incomplete risk for schizophrenia. Possible mechanisms include genome-wide effects of DGCR8 haploinsufficiency. In a proof-of-principle study to assess the power of this model, we used high-quality, whole-genome sequencing of nine individuals with 22q11.2 deletions and extreme phenotypes (schizophrenia, or no psychotic disorder at age >50 years). The schizophrenia group had a greater burden of rare, damaging variants impacting protein-coding neurofunctional genes, including genes involved in neuron projection (nominal P = 0.02, joint burden of three variant types). Variants in the intact 22q11.2 region were not major contributors. Restricting to genes affected by a DGCR8 mechanism tended to amplify between-group differences. Damaging variants in highly conserved long intergenic noncoding RNA genes also were enriched in the schizophrenia group (nominal P = 0.04). The findings support the 22q11.2 deletion model as a threshold-lowering first hit for schizophrenia risk. If applied to a larger and thus better-powered cohort, this appears to be a promising approach to identify genome-wide rare variants in coding and noncoding sequence that perturb gene networks relevant to idiopathic schizophrenia. Similarly designed studies exploiting genetic models may prove useful to help delineate the genetic architecture of other complex phenotypes.
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Suárez-Rama JJ, Arrojo M, Sobrino B, Amigo J, Brenlla J, Agra S, Paz E, Brión M, Carracedo Á, Páramo M, Costas J. Resequencing and association analysis of coding regions at twenty candidate genes suggest a role for rare risk variation at AKAP9 and protective variation at NRXN1 in schizophrenia susceptibility. J Psychiatr Res 2015; 66-67:38-44. [PMID: 25943950 DOI: 10.1016/j.jpsychires.2015.04.013] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/19/2014] [Revised: 04/10/2015] [Accepted: 04/14/2015] [Indexed: 12/20/2022]
Abstract
A fraction of genetic risk to develop schizophrenia may be due to low-frequency variants. This multistep study attempted to find low-frequency variants of high effect at coding regions of eleven schizophrenia susceptibility genes supported by genome-wide association studies (GWAS) and nine genes for the DISC1 interactome, a susceptibility gene-set. During the discovery step, a total of 125 kb per sample were resequenced in 153 schizophrenia patients and 153 controls from Galicia (NW Spain), and the cumulative role of low-frequency variants at a gene or at the DISC1 gene-set were analyzed by burden and variance-based tests. Relevant results were meta-analyzed when appropriate data were available. In addition, case-only putative damaging variants were genotyped in a further 419 cases and 398 controls. The discovery step revealed a protective effect of rare missense variants at NRXN1, a result supported by meta-analysis (OR = 0.67, 95% CI: 0.47-0.94, P = 0.021, based on 3848 patients and 3896 controls from six studies). The follow-up step based on case-only putative damaging variants revealed a promising risk variant at AKAP9. This variant, K873R, reached nominal significance after inclusion of 240 additional Spanish controls from databases. The variant, located in an ADCY2 binding region, is absent from large public databases. Interestingly, GWAS revealed an association between common ADCY2 variants and bipolar disorder, a disorder with considerable genetic overlap with schizophrenia. These data suggest a role of rare missense variants at NRXN1 and AKAP9 in schizophrenia susceptibility, probably related to alteration of the excitatory/inhibitory synaptic balance, deserving further investigation.
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Affiliation(s)
- José Javier Suárez-Rama
- Instituto de Investigación Sanitaria (IDIS) de Santiago de Compostela, Complexo Hospitalario Universitario de Santiago (CHUS), Servizo Galego de Saúde (SERGAS), Santiago de Compostela, Spain; Grupo de Medicina Xenómica, Universidade de Santiago de Compostela, Santiago de Compostela, Spain
| | - Manuel Arrojo
- Instituto de Investigación Sanitaria (IDIS) de Santiago de Compostela, Complexo Hospitalario Universitario de Santiago (CHUS), Servizo Galego de Saúde (SERGAS), Santiago de Compostela, Spain
| | - Beatriz Sobrino
- Instituto de Investigación Sanitaria (IDIS) de Santiago de Compostela, Complexo Hospitalario Universitario de Santiago (CHUS), Servizo Galego de Saúde (SERGAS), Santiago de Compostela, Spain; Fundación Pública Galega de Medicina Xenómica, Complexo Hospitalario Universitario de Santiago (CHUS), Servizo Galego de Saúde (SERGAS), Santiago de Compostela, Spain
| | - Jorge Amigo
- Instituto de Investigación Sanitaria (IDIS) de Santiago de Compostela, Complexo Hospitalario Universitario de Santiago (CHUS), Servizo Galego de Saúde (SERGAS), Santiago de Compostela, Spain; Grupo de Medicina Xenómica, Universidade de Santiago de Compostela, Santiago de Compostela, Spain
| | - Julio Brenlla
- Instituto de Investigación Sanitaria (IDIS) de Santiago de Compostela, Complexo Hospitalario Universitario de Santiago (CHUS), Servizo Galego de Saúde (SERGAS), Santiago de Compostela, Spain; Servizo de Psiquiatría, Complexo Hospitalario Universitario de Santiago(CHUS), Servizo Galego de Saúde (SERGAS), Santiago de Compostela, Spain
| | - Santiago Agra
- Instituto de Investigación Sanitaria (IDIS) de Santiago de Compostela, Complexo Hospitalario Universitario de Santiago (CHUS), Servizo Galego de Saúde (SERGAS), Santiago de Compostela, Spain; Servizo de Psiquiatría, Complexo Hospitalario Universitario de Santiago(CHUS), Servizo Galego de Saúde (SERGAS), Santiago de Compostela, Spain
| | - Eduardo Paz
- Instituto de Investigación Sanitaria (IDIS) de Santiago de Compostela, Complexo Hospitalario Universitario de Santiago (CHUS), Servizo Galego de Saúde (SERGAS), Santiago de Compostela, Spain; Servizo de Psiquiatría, Complexo Hospitalario Universitario de Santiago(CHUS), Servizo Galego de Saúde (SERGAS), Santiago de Compostela, Spain
| | - María Brión
- Instituto de Investigación Sanitaria (IDIS) de Santiago de Compostela, Complexo Hospitalario Universitario de Santiago (CHUS), Servizo Galego de Saúde (SERGAS), Santiago de Compostela, Spain
| | - Ángel Carracedo
- Instituto de Investigación Sanitaria (IDIS) de Santiago de Compostela, Complexo Hospitalario Universitario de Santiago (CHUS), Servizo Galego de Saúde (SERGAS), Santiago de Compostela, Spain; Grupo de Medicina Xenómica, Universidade de Santiago de Compostela, Santiago de Compostela, Spain; Fundación Pública Galega de Medicina Xenómica, Complexo Hospitalario Universitario de Santiago (CHUS), Servizo Galego de Saúde (SERGAS), Santiago de Compostela, Spain
| | - Mario Páramo
- Instituto de Investigación Sanitaria (IDIS) de Santiago de Compostela, Complexo Hospitalario Universitario de Santiago (CHUS), Servizo Galego de Saúde (SERGAS), Santiago de Compostela, Spain; Servizo de Psiquiatría, Complexo Hospitalario Universitario de Santiago(CHUS), Servizo Galego de Saúde (SERGAS), Santiago de Compostela, Spain
| | - Javier Costas
- Instituto de Investigación Sanitaria (IDIS) de Santiago de Compostela, Complexo Hospitalario Universitario de Santiago (CHUS), Servizo Galego de Saúde (SERGAS), Santiago de Compostela, Spain.
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26
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Basmanav FB, Forstner AJ, Fier H, Herms S, Meier S, Degenhardt F, Hoffmann P, Barth S, Fricker N, Strohmaier J, Witt SH, Ludwig M, Schmael C, Moebus S, Maier W, Mössner R, Rujescu D, Rietschel M, Lange C, Nöthen MM, Cichon S. Investigation of the role of TCF4 rare sequence variants in schizophrenia. Am J Med Genet B Neuropsychiatr Genet 2015; 168B:354-62. [PMID: 26010163 DOI: 10.1002/ajmg.b.32318] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/03/2014] [Accepted: 04/13/2015] [Indexed: 12/20/2022]
Abstract
Transcription factor 4 (TCF4) is one of the most robust of all reported schizophrenia risk loci and is supported by several genetic and functional lines of evidence. While numerous studies have implicated common genetic variation at TCF4 in schizophrenia risk, the role of rare, small-sized variants at this locus-such as single nucleotide variants and short indels which are below the resolution of chip-based arrays requires further exploration. The aim of the present study was to investigate the association between rare TCF4 sequence variants and schizophrenia. Exon-targeted resequencing was performed in 190 German schizophrenia patients. Six rare variants at the coding exons and flanking sequences of the TCF4 gene were identified, including two missense variants and one splice site variant. These six variants were then pooled with nine additional rare variants identified in 379 European participants of the 1000 Genomes Project, and all 15 variants were genotyped in an independent German sample (n = 1,808 patients; n = 2,261 controls). These data were then analyzed using six statistical methods developed for the association analysis of rare variants. No significant association (P < 0.05) was found. However, the results from our association and power analyses suggest that further research into the possible involvement of rare TCF4 sequence variants in schizophrenia risk is warranted by the assessment of larger cohorts with higher statistical power to identify rare variant associations.
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Affiliation(s)
- F Buket Basmanav
- Institute of Human Genetics, University of Bonn, Bonn, Germany.,Department of Genomics, Life and Brain Center, Bonn, Germany
| | - Andreas J Forstner
- Institute of Human Genetics, University of Bonn, Bonn, Germany.,Department of Genomics, Life and Brain Center, Bonn, Germany
| | - Heide Fier
- Institute of Human Genetics, University of Bonn, Bonn, Germany.,Department of Genomics, Life and Brain Center, Bonn, Germany.,Department of Genomic Mathematics, University of Bonn, Bonn, Germany
| | - Stefan Herms
- Department of Genomics, Life and Brain Center, Bonn, Germany.,Division of Medical Genetics, University Hospital Basel and Department of Biomedicine, University of Basel, Basel, Switzerland
| | - Sandra Meier
- Department of Genetic Epidemiology in Psychiatry, Central Institute of Mental Health, Medical Faculty Mannheim/Heidelberg University, Mannheim, Germany.,National Center for Register-Based Research, Aarhus University, Aarhus, Denmark
| | - Franziska Degenhardt
- Institute of Human Genetics, University of Bonn, Bonn, Germany.,Department of Genomics, Life and Brain Center, Bonn, Germany
| | - Per Hoffmann
- Institute of Human Genetics, University of Bonn, Bonn, Germany.,Department of Genomics, Life and Brain Center, Bonn, Germany.,Division of Medical Genetics, University Hospital Basel and Department of Biomedicine, University of Basel, Basel, Switzerland.,Institute of Neuroscience and Medicine INM-1, Research Center Juelich, Juelich, Germany
| | - Sandra Barth
- Institute of Human Genetics, University of Bonn, Bonn, Germany.,Department of Genomics, Life and Brain Center, Bonn, Germany
| | - Nadine Fricker
- Institute of Human Genetics, University of Bonn, Bonn, Germany.,Department of Genomics, Life and Brain Center, Bonn, Germany
| | - Jana Strohmaier
- Department of Genetic Epidemiology in Psychiatry, Central Institute of Mental Health, Medical Faculty Mannheim/Heidelberg University, Mannheim, Germany
| | - Stephanie H Witt
- Department of Genetic Epidemiology in Psychiatry, Central Institute of Mental Health, Medical Faculty Mannheim/Heidelberg University, Mannheim, Germany
| | - Michael Ludwig
- Department of Clinical Chemistry and Clinical Pharmacology, University of Bonn, Bonn, Germany
| | - Christine Schmael
- Institute of Human Genetics, University of Bonn, Bonn, Germany.,Department of Genetic Epidemiology in Psychiatry, Central Institute of Mental Health, Medical Faculty Mannheim/Heidelberg University, Mannheim, Germany
| | - Susanne Moebus
- Centre of Urban Epidemiology, Institute of Medical Informatics, Biometry and Epidemiology, Essen, Germany
| | - Wolfgang Maier
- Department of Psychiatry and Psychotherapy, University of Bonn, Bonn, Germany
| | - Rainald Mössner
- Department of Psychiatry and Psychotherapy, University of Bonn, Bonn, Germany.,Department of Psychiatry, University of Tübingen
| | - Dan Rujescu
- Department of Psychiatry, University of Halle, Halle, Germany
| | - Marcella Rietschel
- Department of Genetic Epidemiology in Psychiatry, Central Institute of Mental Health, Medical Faculty Mannheim/Heidelberg University, Mannheim, Germany
| | - Christoph Lange
- Department of Genomic Mathematics, University of Bonn, Bonn, Germany.,German Center for Neurodegenerative Diseases (DZNE), Bonn, Germany.,Department of Biostatistics, Harvard School of Public Health, Boston, Massachusetts
| | - Markus M Nöthen
- Institute of Human Genetics, University of Bonn, Bonn, Germany.,Department of Genomics, Life and Brain Center, Bonn, Germany
| | - Sven Cichon
- Institute of Human Genetics, University of Bonn, Bonn, Germany.,Department of Genomics, Life and Brain Center, Bonn, Germany.,Division of Medical Genetics, University Hospital Basel and Department of Biomedicine, University of Basel, Basel, Switzerland.,Institute of Neuroscience and Medicine INM-1, Research Center Juelich, Juelich, Germany
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27
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Eells JB, Varela-Stokes A, Guo-Ross SX, Kummari E, Smith HM, Cox AD, Lindsay DS. Chronic Toxoplasma gondii in Nurr1-null heterozygous mice exacerbates elevated open field activity. PLoS One 2015; 10:e0119280. [PMID: 25855987 PMCID: PMC4391871 DOI: 10.1371/journal.pone.0119280] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2014] [Accepted: 01/20/2015] [Indexed: 12/19/2022] Open
Abstract
Latent infection with Toxoplasma gondii is common in humans (approximately 30% of the global population) and is a significant risk factor for schizophrenia. Since prevalence of T. gondii infection is far greater than prevalence of schizophrenia (0.5-1%), genetic risk factors are likely also necessary to contribute to schizophrenia. To test this concept in an animal model, Nurr1-null heterozygous (+/-) mice and wild-type (+/+) mice were evaluate using an emergence test, activity in an open field and with a novel object, response to bobcat urine and prepulse inhibition of the acoustic startle response (PPI) prior to and 6 weeks after infection with T. gondii. In the emergence test, T. gondii infection significantly decreased the amount of time spent in the cylinder. Toxoplasma gondii infection significantly elevated open field activity in both +/+ and +/- mice but this increase was significantly exacerbated in +/- mice. T. gondii infection reduced PPI in male +/- mice but this was not statistically significant. Aversion to bobcat urine was abolished by T. gondii infection in +/+ mice. In female +/- mice, aversion to bobcat urine remained after T. gondii infection while the male +/- mice showed no aversion to bobcat urine. Antibody titers of infected mice were a critical variable associated with changes in open field activity, such that an inverted U shaped relationship existed between antibody titers and the percent change in open field activity with a significant increase in activity at low and medium antibody titers but no effect at high antibody titers. These data demonstrate that the Nurr1 +/- genotype predisposes mice to T. gondii-induced alterations in behaviors that involve dopamine neurotransmission and are associated with symptoms of schizophrenia. We propose that these alterations in murine behavior were due to further exacerbation of the altered dopamine neurotransmission in Nurr1 +/- mice.
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Affiliation(s)
- Jeffrey B. Eells
- Department of Basic Sciences, College of Veterinary Medicine, Mississippi State University, Mississippi State, Mississippi, United States of America
- * E-mail:
| | - Andrea Varela-Stokes
- Department of Basic Sciences, College of Veterinary Medicine, Mississippi State University, Mississippi State, Mississippi, United States of America
| | - Shirley X. Guo-Ross
- Department of Basic Sciences, College of Veterinary Medicine, Mississippi State University, Mississippi State, Mississippi, United States of America
| | - Evangel Kummari
- Department of Basic Sciences, College of Veterinary Medicine, Mississippi State University, Mississippi State, Mississippi, United States of America
| | - Holly M. Smith
- Department of Basic Sciences, College of Veterinary Medicine, Mississippi State University, Mississippi State, Mississippi, United States of America
| | - Arin D. Cox
- Department of Basic Sciences, College of Veterinary Medicine, Mississippi State University, Mississippi State, Mississippi, United States of America
| | - David S. Lindsay
- Department of Biomedical Sciences & Pathobiology, Virginia–Maryland Regional College of Veterinary Medicine, Virginia Tech, Blacksburg, Virginia, United States of America
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29
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Nascimento JM, Martins-de-Souza D. The proteome of schizophrenia. NPJ SCHIZOPHRENIA 2015; 1:14003. [PMID: 27336025 PMCID: PMC4849438 DOI: 10.1038/npjschz.2014.3] [Citation(s) in RCA: 82] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/19/2014] [Revised: 10/28/2014] [Accepted: 10/30/2014] [Indexed: 12/24/2022]
Abstract
On observing schizophrenia from a clinical point of view up to its molecular basis, one may conclude that this is likely to be one of the most complex human disorders to be characterized in all aspects. Such complexity is the reflex of an intricate combination of genetic and environmental components that influence brain functions since pre-natal neurodevelopment, passing by brain maturation, up to the onset of disease and disease establishment. The perfect function of tissues, organs, systems, and finally the organism depends heavily on the proper functioning of cells. Several lines of evidence, including genetics, genomics, transcriptomics, neuropathology, and pharmacology, have supported the idea that dysfunctional cells are causative to schizophrenia. Together with the above-mentioned techniques, proteomics have been contributing to understanding the biochemical basis of schizophrenia at the cellular and tissue level through the identification of differentially expressed proteins and consequently their biochemical pathways, mostly in the brain tissue but also in other cells. In addition, mass spectrometry-based proteomics have identified and precisely quantified proteins that may serve as biomarker candidates to prognosis, diagnosis, and medication monitoring in peripheral tissue. Here, we review all data produced by proteomic investigation in the last 5 years using tissue and/or cells from schizophrenic patients, focusing on postmortem brain tissue and peripheral blood serum and plasma. This information has provided integrated pictures of the biochemical systems involved in the pathobiology, and has suggested potential biomarkers, and warrant potential targets to alternative treatment therapies to schizophrenia.
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Affiliation(s)
- Juliana M Nascimento
- Laboratory of Neuroproteomics, Department of Biochemistry and Tissue Biology, Institute of Biology, University of Campinas (UNICAMP), Campinas, Sao Paulo, Brazil
- D’Or Institute for Research and Education (IDOR), Rio de Janeiro, Brazil
| | - Daniel Martins-de-Souza
- Laboratory of Neuroproteomics, Department of Biochemistry and Tissue Biology, Institute of Biology, University of Campinas (UNICAMP), Campinas, Sao Paulo, Brazil
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Drogemöller BI, Niehaus DJH, Chiliza B, van der Merwe L, Asmal L, Malhotra AK, Wright GEB, Emsley R, Warnich L. Patterns of variation influencing antipsychotic treatment outcomes in South African first-episode schizophrenia patients. Pharmacogenomics 2015; 15:189-99. [PMID: 24444409 DOI: 10.2217/pgs.13.218] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
AIM Many antipsychotic pharmacogenetics studies have been performed examining candidate genes or known variation; however, our understanding of the genetic factors involved in antipsychotic pharmacogenetic traits remains limited. MATERIALS & METHODS A well-characterized cohort of first-episode schizophrenia (FES) patients was used to identify a subset of nonresponders and responders to antipsychotic treatment for exome sequencing (n = 11). The variation observed in the responders and nonresponders was subsequently compared and a prioritization strategy was employed to identify variants for genotyping in the entire FES cohort (n = 103) as well as an additional Xhosa schizophrenia cohort (n = 222). RESULTS Examination of coding variation revealed a potential role for rare loss-of-function variants in treatment response outcomes. One variant, rs11368509, was found to be weakly associated with better treatment outcomes in the FES cohort (p = 0.057) and the Xhosa schizophrenia cohort (p = 0.016). In addition, the majority of the loss-of-function variation that was considered likely to be involved in antipsychotic treatment response was either novel or rare in Asian and European populations. CONCLUSION This pilot study has highlighted the importance of exome sequencing for antipsychotic pharmacogenomics studies, particularly in African individuals. Furthermore, the results emphasize once again the complexity of antipsychotic pharmacogenomics and the need for future research.
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Affiliation(s)
- Britt I Drogemöller
- Department of Genetics, Stellenbosch University, Private Bag XI, Matieland, 7602, Western Cape, South Africa
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Kato T. Whole genome/exome sequencing in mood and psychotic disorders. Psychiatry Clin Neurosci 2015; 69:65-76. [PMID: 25319632 DOI: 10.1111/pcn.12247] [Citation(s) in RCA: 56] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 10/09/2014] [Indexed: 02/06/2023]
Abstract
Recent developments in DNA sequencing technologies have allowed for genetic studies using whole genome or exome analysis, and these have been applied in the study of mood and psychotic disorders, including bipolar disorder, depression, schizophrenia, and schizoaffective disorder. In this review, the current situation, recent findings, methodological problems, and future directions of whole genome/exome analysis studies of these disorders are summarized. Whole genome/exome studies of bipolar disorder have included pedigree analysis and case-control studies, demonstrating the role of previously implicated pathways, such as calcium signaling, cyclic adenosine monophosphate response element binding protein (CREB) signaling, and potassium channels. Extensive analysis of trio families and case-control studies showed that de novo mutations play a role in the genetic architecture of schizophrenia and indicated that mutations in several molecular pathways, including chromatin regulation, activity-regulated cytoskeleton, post-synaptic density, N-methyl-D-aspartate receptor, and targets of fragile X mental retardation protein, are associated with this disorder. Depression is a heterogeneous group of diseases and studies using exome analysis have been conducted to identify rare mutations causing Mendelian diseases that accompany depression. In the near future, clarification of the genetic architecture of bipolar disorder and schizophrenia is expected. Identification of causative mutations using these new technologies will facilitate neurobiological studies of these disorders.
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Affiliation(s)
- Tadafumi Kato
- Laboratory for Molecular Dynamics of Mental Disorders, RIKEN Brain Science Institute, Wako, Japan
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Copy number variable microRNAs in schizophrenia and their neurodevelopmental gene targets. Biol Psychiatry 2015; 77:158-66. [PMID: 25034949 PMCID: PMC4464826 DOI: 10.1016/j.biopsych.2014.05.011] [Citation(s) in RCA: 48] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/04/2014] [Revised: 05/16/2014] [Accepted: 05/18/2014] [Indexed: 01/12/2023]
Abstract
BACKGROUND MicroRNAs (miRNAs) are key regulators of gene expression in the human genome and may contribute to risk for neuropsychiatric disorders. miRNAs play an acknowledged role in the strongest of genetic risk factors for schizophrenia, 22q11.2 deletions. We hypothesized that in schizophrenia there would be an enrichment of other rare copy number variants (CNVs) that overlap miRNAs. METHODS Using high-resolution genome-wide microarrays and rigorous methods, we compared the miRNA content of rare CNVs in well-characterized cohorts of schizophrenia cases (n = 420) and comparison subjects, excluding 22q11.2 CNVs. We also performed a gene-set enrichment analysis of the predicted miRNA target genes. RESULTS The schizophrenia group was enriched for the proportion of individuals with a rare CNV overlapping a miRNA (3.29-fold increase over comparison subjects, p < .0001). The presence of a rare CNV overlapping a miRNA remained a significant predictor of schizophrenia case status (p = .0072) in a multivariate logistic regression model correcting for total CNV size. In contrast, comparable analyses correcting for CNV size showed no enrichment of rare CNVs overlapping protein-coding genes. A gene-set enrichment analysis indicated that predicted target genes of recurrent CNV-overlapped miRNAs in schizophrenia may be functionally enriched for neurodevelopmental processes, including axonogenesis and neuron projection development. Predicted gene targets driving these results included CAPRIN1, NEDD4, NTRK2, PAK2, RHOA, and SYNGAP1. CONCLUSIONS These data are the first to demonstrate a genome-wide role for CNVs overlapping miRNAs in the genetic risk for schizophrenia. The results provide support for an expanded multihit model of causation, with potential implications for miRNA-based therapeutics.
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Kerner B. Toward a Deeper Understanding of the Genetics of Bipolar Disorder. Front Psychiatry 2015; 6:105. [PMID: 26283973 PMCID: PMC4522874 DOI: 10.3389/fpsyt.2015.00105] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/31/2015] [Accepted: 07/08/2015] [Indexed: 12/15/2022] Open
Abstract
Bipolar disorder is a common, complex psychiatric disorder characterized by mania and depression. The disease aggregates in families, but despite much effort, it has been difficult to delineate the basic genetic model or identify specific genetic risk factors. Not only single gene Mendelian transmission and common variant hypotheses but also multivariate threshold models and oligogenic quasi-Mendelian modes of inheritance have dominated the discussion at times. Almost complete sequence information of the human genome and falling sequencing costs now offer the opportunity to test these models in families in which the disorder is transmitted over several generations. Exome-wide sequencing studies have revealed an astonishing number of rare and potentially damaging mutations in brain-expressed genes that could have contributed to the disease manifestation. However, the statistical analysis of these data has been challenging, because genetic risk factors displayed a high degree of dissimilarity across families. This scenario is not unique to bipolar disorder, but similar results have also been found in schizophrenia, a potentially related psychiatric disorder. Recently, our group has published data which supported an oligogenic genetic model of transmission in a family with bipolar disorder. In this family, three affected siblings shared rare, damaging mutations in multiple genes, which were linked to stress response pathways. These pathways are also the target for drugs frequently used to treat bipolar disorder. This article discusses these findings in the context of previously proclaimed disease models and suggests future research directions, including biological confirmation and phenotype stratification as an approach to disease heterogeneity.
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Affiliation(s)
- Berit Kerner
- Semel Institute for Neuroscience and Human Behavior, University of California, Los Angeles , Los Angeles, CA , USA
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Abstract
Virtually all psychiatric traits are genetically complex. This article discusses the genetics of complex traits in psychiatry. The complexity is accounted for by numerous factors, including multiple risk alleles, epistasis, and epigenetic effects such as methylation. Risk alleles can individually be common or rare, and can include, for example, single nucleotide polymorphisms and copy number variants that are transmitted or are new mutations, and other kinds of variation. Many different kinds of variation can be important for trait risk, either together in various proportions or as different factors in different subjects. Until more recently, approaches to complex traits were limited, and consequently only a few variants, usually of individually minor effect, were identified. At the present time, a much richer armamentarium exists that includes the routine application of genome-wide association studies and next-generation high-throughput sequencing and the combination of this information with other biologically relevant information, such as expression data. We have also seen the emergence of large meta-analysis and mega-analysis consortia. These developments are extremely important for psychiatric genetics, have advanced the field substantially, and promise formidable gains in the years to come as they are applied more widely.
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Pocklington AJ, O'Donovan M, Owen MJ. The synapse in schizophrenia. Eur J Neurosci 2014; 39:1059-67. [PMID: 24712986 DOI: 10.1111/ejn.12489] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2013] [Revised: 12/19/2013] [Accepted: 12/20/2013] [Indexed: 02/06/2023]
Abstract
It has been several decades since synaptic dysfunction was first suggested to play a role in schizophrenia, but only in the last few years has convincing evidence been obtained as progress has been made in elucidating the genetic underpinnings of the disorder. In the intervening years much has been learned concerning the complex macromolecular structure of the synapse itself, and genetic studies are now beginning to draw upon these advances. Here we outline our current understanding of the genetic architecture of schizophrenia and examine the evidence for synaptic involvement. A strong case can now be made that disruption of glutamatergic signalling pathways regulating synaptic plasticity contributes to the aetiology of schizophrenia.
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Affiliation(s)
- Andrew J Pocklington
- MRC Centre for Neuropsychiatric Genetics and Genomics, Institute of Psychological Medicine and Clinical Neurosciences, Cardiff University School of Medicine, Hadyn Ellis Building, Maindy Road, Cathays, Cardiff, CF24 4HQ, UK
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Merico D, Costain G, Butcher NJ, Warnica W, Ogura L, Alfred SE, Brzustowicz LM, Bassett AS. MicroRNA Dysregulation, Gene Networks, and Risk for Schizophrenia in 22q11.2 Deletion Syndrome. Front Neurol 2014; 5:238. [PMID: 25484875 PMCID: PMC4240070 DOI: 10.3389/fneur.2014.00238] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2014] [Accepted: 11/02/2014] [Indexed: 01/20/2023] Open
Abstract
The role of microRNAs (miRNAs) in the etiology of schizophrenia is increasingly recognized. Microdeletions at chromosome 22q11.2 are recurrent structural variants that impart a high risk for schizophrenia and are found in up to 1% of all patients with schizophrenia. The 22q11.2 deletion region overlaps gene DGCR8, encoding a subunit of the miRNA microprocessor complex. We identified miRNAs overlapped by the 22q11.2 microdeletion and for the first time investigated their predicted target genes, and those implicated by DGCR8, to identify targets that may be involved in the risk for schizophrenia. The 22q11.2 region encompasses seven validated or putative miRNA genes. Employing two standard prediction tools, we generated sets of predicted target genes. Functional enrichment profiles of the 22q11.2 region miRNA target genes suggested a role in neuronal processes and broader developmental pathways. We then constructed a protein interaction network of schizophrenia candidate genes and interaction partners relevant to brain function, independent of the 22q11.2 region miRNA mechanisms. We found that the predicted gene targets of the 22q11.2 deletion miRNAs, and targets of the genome-wide miRNAs predicted to be dysregulated by DGCR8 hemizygosity, were significantly represented in this schizophrenia network. The findings provide new insights into the pathway from 22q11.2 deletion to expression of schizophrenia, and suggest that hemizygosity of the 22q11.2 region may have downstream effects implicating genes elsewhere in the genome that are relevant to the general schizophrenia population. These data also provide further support for the notion that robust genetic findings in schizophrenia may converge on a reasonable number of final pathways.
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Affiliation(s)
- Daniele Merico
- The Centre for Applied Genomics and Program in Genetics and Genome Biology, The Hospital for Sick Children , Toronto, ON , Canada
| | - Gregory Costain
- Clinical Genetics Research Program, Centre for Addiction and Mental Health , Toronto, ON , Canada
| | - Nancy J Butcher
- Clinical Genetics Research Program, Centre for Addiction and Mental Health , Toronto, ON , Canada ; Institute of Medical Science, University of Toronto , Toronto, ON , Canada
| | - William Warnica
- Clinical Genetics Research Program, Centre for Addiction and Mental Health , Toronto, ON , Canada
| | - Lucas Ogura
- Clinical Genetics Research Program, Centre for Addiction and Mental Health , Toronto, ON , Canada
| | - Simon E Alfred
- Clinical Genetics Research Program, Centre for Addiction and Mental Health , Toronto, ON , Canada
| | - Linda M Brzustowicz
- Department of Genetics and the Human Genetics Institute of New Jersey, Rutgers University , Piscataway, NJ , USA
| | - Anne S Bassett
- Clinical Genetics Research Program, Centre for Addiction and Mental Health , Toronto, ON , Canada ; Institute of Medical Science, University of Toronto , Toronto, ON , Canada ; The Dalglish Family Hearts and Minds Clinic for 22q11.2 Deletion Syndrome, Toronto General Hospital, University Health Network , Toronto, ON , Canada ; Department of Psychiatry, Toronto General Research Institute, University Health Network , Toronto, ON , Canada ; Department of Psychiatry, University of Toronto , Toronto, ON , Canada
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Morris BJ, Pratt JA. Novel treatment strategies for schizophrenia from improved understanding of genetic risk. Clin Genet 2014; 86:401-11. [PMID: 25142969 DOI: 10.1111/cge.12485] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2014] [Revised: 08/15/2014] [Accepted: 08/16/2014] [Indexed: 01/19/2023]
Abstract
Recent years have seen significant advances in our understanding of the genetic basis of schizophrenia. In particular, genome-wide approaches have suggested the involvement of many common genetic variants of small effect, together with a few rare variants exerting relatively large effects. While unequivocal identification of the relevant genes has, for the most part, remained elusive, the genes revealed as potential candidates can in many cases be clustered into functionally related groups which are potentially open to therapeutic intervention. In this review, we summarise this information, focusing on the accumulating evidence that genetic dysfunction at glutamatergic synapses and post-synaptic signalling complexes contributes to the aetiology of the disease. In particular, there is converging support for involvement of post-synaptic JNK pathways in disease aetiology. An expansion of our neurobiological knowledge of the basis of schizophrenia is urgently needed, yet some promising novel pharmacological targets can already be discerned.
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Affiliation(s)
- B J Morris
- Psychiatric Research Institute of Neuroscience in Glasgow (PsyRING), University of Glasgow, Glasgow, UK; Institute of Neuroscience and Psychology, School of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, UK
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Wang C, Koide T, Kimura H, Kunimoto S, Yoshimi A, Nakamura Y, Kushima I, Banno M, Kawano N, Takasaki Y, Xing J, Noda Y, Mouri A, Aleksic B, Ikeda M, Okada T, Iidaka T, Inada T, Iwata N, Ozaki N. Novel rare variants in F-box protein 45 (FBXO45) in schizophrenia. Schizophr Res 2014; 157:149-56. [PMID: 24878430 DOI: 10.1016/j.schres.2014.04.032] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/01/2013] [Revised: 03/31/2014] [Accepted: 04/23/2014] [Indexed: 10/25/2022]
Abstract
The ubiquitin ligase F-box protein 45 (FBXO45) is critical for synaptogenesis, neuronal migration, and synaptic transmission. FBXO45 is included in the 3q29 microdeletion region that confers a significant risk for schizophrenia, as shown by rare structural variant studies. Thus, FBXO45 is considered a prominent candidate for mediating schizophrenia pathogenesis. Here, we investigated rare, deleterious single nucleotide variants (SNVs) as well as small insertions and deletions (INDELs) in FBXO45 that may contribute to schizophrenia susceptibility. Using Sanger sequencing, we performed mutation screening in FBXO45 exon regions in 337 schizophrenia patients. Novel missense or nonsense variants were followed up with a genetic association study in an independent sample set of 601 schizophrenia patients and 916 controls, a case report for assessing the clinical consequence of the mutations, a pedigree study for measuring mutation inheritance in the proband's family, bioinformatics analyses for evaluating mutation effect on protein structure and function, and mRNA expression analysis for examining mutation transcriptional influence on FBXO45 expression. One heterozygous, novel, and rare missense mutation (R108C) was identified in a single schizophrenia patient and in his healthy mother. At age 20, this patient was diagnosed with paranoid schizophrenia and carried some clinical features of 3q29 deletion phenotypes, including premorbid IQ decline. With follow-up genotyping, this mutation was not found in either the schizophrenia group (0/601) or the healthy control group (0/916). Bioinformatics analyses predicted that R108C probably pathologically impacted the structure and function of the FBXO45 protein. The relative expression of FBXO45 in SCZ case with R108C mutation was relatively low when compared to 50 schizophrenia patients and 52 healthy controls. The R108C mutation in FBXO45 is a rare variant with a modest effect on schizophrenia risk that may disrupt the structure and function of the FBXO45 protein. Our findings also suggest that FBXO45 may be a new attractive candidate gene for schizophrenia.
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Affiliation(s)
- Chenyao Wang
- Department of Psychiatry, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Takayoshi Koide
- Department of Psychiatry, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Hiroki Kimura
- Department of Psychiatry, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Shohko Kunimoto
- Department of Psychiatry, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Akira Yoshimi
- Department of Psychiatry, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Yukako Nakamura
- Department of Psychiatry, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Itaru Kushima
- Department of Psychiatry, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Masahiro Banno
- Department of Psychiatry, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Naoko Kawano
- Department of Psychiatry, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Yuto Takasaki
- Department of Psychiatry, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Jingrui Xing
- Department of Psychiatry, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Yukihiro Noda
- Division of Clinical Sciences and Neuropsychopharmacology, Graduate School of Pharmacy, Meijo University, Nagoya, Japan
| | - Akihiro Mouri
- Division of Clinical Sciences and Neuropsychopharmacology, Graduate School of Pharmacy, Meijo University, Nagoya, Japan
| | - Branko Aleksic
- Department of Psychiatry, Nagoya University Graduate School of Medicine, Nagoya, Japan.
| | - Masashi Ikeda
- Department of Psychiatry, School of Medicine, Fujita Health University, Toyoake, Aichi, Japan
| | - Takashi Okada
- Department of Psychiatry, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Tetsuya Iidaka
- Department of Psychiatry, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Toshiya Inada
- Institute of Neuropsychiatry, Seiwa Hospital, Tokyo, Japan
| | - Nakao Iwata
- Department of Psychiatry, School of Medicine, Fujita Health University, Toyoake, Aichi, Japan
| | - Norio Ozaki
- Department of Psychiatry, Nagoya University Graduate School of Medicine, Nagoya, Japan
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Grarup N, Sandholt CH, Hansen T, Pedersen O. Genetic susceptibility to type 2 diabetes and obesity: from genome-wide association studies to rare variants and beyond. Diabetologia 2014; 57:1528-41. [PMID: 24859358 DOI: 10.1007/s00125-014-3270-4] [Citation(s) in RCA: 127] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/13/2013] [Accepted: 04/22/2014] [Indexed: 12/29/2022]
Abstract
During the past 7 years, genome-wide association studies have shed light on the contribution of common genomic variants to the genetic architecture of type 2 diabetes, obesity and related intermediate phenotypes. The discoveries have firmly established more than 175 genomic loci associated with these phenotypes. Despite the tight correlation between type 2 diabetes and obesity, these conditions do not appear to share a common genetic background, since they have few genetic risk loci in common. The recent genetic discoveries do however highlight specific details of the interplay between the pathogenesis of type 2 diabetes, insulin resistance and obesity. The focus is currently shifting towards investigations of data from targeted array-based genotyping and exome and genome sequencing to study the individual and combined effect of low-frequency and rare variants in metabolic disease. Here we review recent progress as regards the concepts, methodologies and derived outcomes of studies of the genetics of type 2 diabetes and obesity, and discuss avenues to be investigated in the future within this research field.
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Affiliation(s)
- Niels Grarup
- The Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, DIKU Building, Universitetsparken 1, 2100, Copenhagen Ø, Denmark,
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Nutt DJ, Need AC. Where now for schizophrenia research? Eur Neuropsychopharmacol 2014; 24:1181-7. [PMID: 24950818 DOI: 10.1016/j.euroneuro.2014.05.012] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/31/2014] [Revised: 05/17/2014] [Accepted: 05/19/2014] [Indexed: 12/28/2022]
Abstract
Schizophrenia continues to pose a serious challenge to neuroscience and psychiatry as well as to health care systems and to the patients and families who suffer this terrible and disabling illness. Major developments in the past few months in both genetics and drug development oblige us to consider novel drug discovery tactics for future schizophrenia research. Here we review what we consider to be the key issues and some suggested solutions.
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Affiliation(s)
- David J Nutt
- Division of Brain Sciences, Department of Medicine, Imperial College London, London, United Kingdom.
| | - Anna C Need
- Division of Brain Sciences, Department of Medicine, Imperial College London, London, United Kingdom.
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41
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Risk genes for schizophrenia: Translational opportunities for drug discovery. Pharmacol Ther 2014; 143:34-50. [DOI: 10.1016/j.pharmthera.2014.02.003] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2014] [Accepted: 01/31/2014] [Indexed: 12/11/2022]
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Towards a molecular characterization of autism spectrum disorders: an exome sequencing and systems approach. Transl Psychiatry 2014; 4:e394. [PMID: 24893065 PMCID: PMC4080319 DOI: 10.1038/tp.2014.38] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/12/2014] [Accepted: 04/22/2014] [Indexed: 12/30/2022] Open
Abstract
The hypothetical 'AXAS' gene network model that profiles functional patterns of heterogeneous DNA variants overrepresented in autism spectrum disorder (ASD), X-linked intellectual disability, attention deficit and hyperactivity disorder and schizophrenia was used in this current study to analyze whole exome sequencing data from an Australian ASD cohort. An optimized DNA variant filtering pipeline was used to identify loss-of-function DNA variations. Inherited variants from parents with a broader autism phenotype and de novo variants were found to be significantly associated with ASD. Gene ontology analysis revealed that putative rare causal variants cluster in key neurobiological processes and are overrepresented in functions involving neuronal development, signal transduction and synapse development including the neurexin trans-synaptic complex. We also show how a complex gene network model can be used to fine map combinations of inherited and de novo variations in families with ASD that converge in the L1CAM pathway. Our results provide an important step forward in the molecular characterization of ASD with potential for developing a tool to analyze the pathogenesis of individual affected families.
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43
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Lohmueller KE. The impact of population demography and selection on the genetic architecture of complex traits. PLoS Genet 2014; 10:e1004379. [PMID: 24875776 PMCID: PMC4038606 DOI: 10.1371/journal.pgen.1004379] [Citation(s) in RCA: 98] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2013] [Accepted: 03/28/2014] [Indexed: 02/06/2023] Open
Abstract
Population genetic studies have found evidence for dramatic population growth in recent human history. It is unclear how this recent population growth, combined with the effects of negative natural selection, has affected patterns of deleterious variation, as well as the number, frequency, and effect sizes of mutations that contribute risk to complex traits. Because researchers are performing exome sequencing studies aimed at uncovering the role of low-frequency variants in the risk of complex traits, this topic is of critical importance. Here I use simulations under population genetic models where a proportion of the heritability of the trait is accounted for by mutations in a subset of the exome. I show that recent population growth increases the proportion of nonsynonymous variants segregating in the population, but does not affect the genetic load relative to a population that did not expand. Under a model where a mutation's effect on a trait is correlated with its effect on fitness, rare variants explain a greater portion of the additive genetic variance of the trait in a population that has recently expanded than in a population that did not recently expand. Further, when using a single-marker test, for a given false-positive rate and sample size, recent population growth decreases the expected number of significant associations with the trait relative to the number detected in a population that did not expand. However, in a model where there is no correlation between a mutation's effect on fitness and the effect on the trait, common variants account for much of the additive genetic variance, regardless of demography. Moreover, here demography does not affect the number of significant associations detected. These findings suggest recent population history may be an important factor influencing the power of association tests and in accounting for the missing heritability of certain complex traits.
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Affiliation(s)
- Kirk E Lohmueller
- Department of Ecology and Evolutionary Biology, Interdepartmental Program in Bioinformatics, University of California, Los Angeles, California, United States of America
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Resequencing the susceptibility gene, ITGAM, identifies two functionally deleterious rare variants in systemic lupus erythematosus cases. Arthritis Res Ther 2014; 16:R114. [PMID: 24886912 PMCID: PMC4060450 DOI: 10.1186/ar4566] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2013] [Accepted: 05/07/2014] [Indexed: 12/16/2022] Open
Abstract
Introduction The majority of the genetic variance of systemic lupus erythematosus (SLE) remains unexplained by the common disease-common variant hypothesis. Rare variants, which are not detectable by genome-wide association studies because of their low frequencies, are predicted to explain part of this ”missing heritability.” However, recent studies identifying rare variants within known disease-susceptibility loci have failed to show genetic associations because of their extremely low frequencies, leading to the questioning of the contribution of rare variants to disease susceptibility. A common (minor allele frequency = 17.4% in cases) nonsynonymous coding variant rs1143679 (R77H) in ITGAM (CD11b), which forms half of the heterodimeric integrin receptor, complement receptor 3 (CR3), is robustly associated with SLE and has been shown to impair CR3-mediated phagocytosis. Methods We resequenced ITGAM in 73 SLE cases and identified two previously unidentified, case-specific nonsynonymous variants, F941V and G1145S. Both variants were genotyped in 2,107 and 949 additional SLE cases, respectively, to estimate their frequencies in a disease population. An in vitro model was used to assess the impact of F941V and G1145S, together with two nonsynonymous ITGAM polymorphisms, A858V (rs1143683) and M441T (rs11861251), on CR3-mediated phagocytosis. A paired two-tailed t test was used to compare the phagocytic capabilities of each variant with that of wild-type CR3. Results Both rare variants, F941V and G1145S, significantly impair CR3-mediated phagocytosis in an in vitro model (61% reduction, P = 0.006; 26% reduction, P = 0.0232). However, neither of the common variants, M441T and A858V, had an effect on phagocytosis. Neither rare variant was observed again in the genotyping of additional SLE cases, suggesting that there frequencies are extremely low. Conclusions Our results add further evidence to the functional importance of ITGAM in SLE pathogenesis through impaired phagocytosis. Additionally, this study provides a new example of the identification of rare variants in common-allele-associated loci, which, because of their extremely low frequencies, are not statistically associated. However, the demonstration of their functional effects adds support to their contribution to disease risk, and questions the current notion of dismissing the contribution of very rare variants on purely statistical analyses.
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Cardno AG, Owen MJ. Genetic relationships between schizophrenia, bipolar disorder, and schizoaffective disorder. Schizophr Bull 2014; 40:504-15. [PMID: 24567502 PMCID: PMC3984527 DOI: 10.1093/schbul/sbu016] [Citation(s) in RCA: 173] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
There is substantial evidence for partial overlap of genetic influences on schizophrenia and bipolar disorder, with family, twin, and adoption studies showing a genetic correlation between the disorders of around 0.6. Results of genome-wide association studies are consistent with commonly occurring genetic risk variants, contributing to both the shared and nonshared aspects, while studies of large, rare chromosomal structural variants, particularly copy number variants, show a stronger influence on schizophrenia than bipolar disorder to date. Schizoaffective disorder has been less investigated but shows substantial familial overlap with both schizophrenia and bipolar disorder. A twin analysis is consistent with genetic influences on schizoaffective episodes being entirely shared with genetic influences on schizophrenic and manic episodes, while association studies suggest the possibility of some relatively specific genetic influences on broadly defined schizoaffective disorder, bipolar subtype. Further insights into genetic relationships between these disorders are expected as studies continue to increase in sample size and in technical and analytical sophistication, information on phenotypes beyond clinical diagnoses are increasingly incorporated, and approaches such as next-generation sequencing identify additional types of genetic risk variant.
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Affiliation(s)
- Alastair G. Cardno
- Academic Unit of Psychiatry and Behavioural Sciences, University of Leeds, Leeds, UK;,*To whom correspondence should be addressed; Academic Unit of Psychiatry and Behavioural Sciences, Leeds Institute of Health Sciences, University of Leeds, Charles Thackrah Building, 101 Clarendon Road, Leeds LS2 9LJ, UK; tel: +44 113 3437260, fax: +44 113 3436997, e-mail:
| | - Michael J. Owen
- MRC Centre for Neuropsychiatric Genetics and Genomics, and Neuroscience and Mental Health Research Institute, Cardiff University, Cardiff, UK
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Abstract
Significant progress is being made in defining the genetic etiology of schizophrenia. As the list of implicated genes grows, parallel developments in gene editing technology provide new methods to investigate gene function in model systems. The confluence of these two research fields--gene discovery and functional biology--may offer novel insights into schizophrenia etiology. We review recent advances in these fields, consider the likely obstacles to progress, and consider strategies as to how these can be overcome.
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Affiliation(s)
- Shane E. McCarthy
- Stanley Institute of Cognitive Genomics, Cold Spring Harbor Laboratory, Woodbury, NY
| | - W. Richard McCombie
- Stanley Institute of Cognitive Genomics, Cold Spring Harbor Laboratory, Woodbury, NY
| | - Aiden Corvin
- Department of Psychiatry & Neuropsychiatric Genetics Research Group, Institute of Molecular Medicine, Trinity College Dublin, Dublin, Ireland,*To whom correspondence should be addressed; Department of Psychiatry & Neuropsychiatric Genetics Research Group, Institute of Molecular Medicine, Trinity College Dublin, Dublin 2, Ireland; tel: +353-1-8962467, fax: +353-1-8963405, e-mail:
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Lowther C, Costain G, Melvin R, Stavropoulos DJ, Lionel AC, Marshall CR, Scherer SW, Bassett AS. Adult expression of a 3q13.31 microdeletion. Mol Cytogenet 2014; 7:23. [PMID: 24650298 PMCID: PMC4022390 DOI: 10.1186/1755-8166-7-23] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2013] [Accepted: 03/11/2014] [Indexed: 11/30/2022] Open
Abstract
Background The emerging 3q13.31 microdeletion syndrome appears to encompass diverse neurodevelopmental conditions. However, the 3q13.31 deletion is rare and few adult cases have yet been reported. We examined a cohort with schizophrenia (n = 459) and adult control subjects (n = 26,826) using high-resolution microarray technology for deletions and duplications at the 3q13.31 locus. Results We report on the extended adult phenotype associated with a 3q13.31 microdeletion in a 41-year-old male proband with schizophrenia and a nonverbal learning disability. He was noted to have a speech impairment, delayed motor skills, and other features consistent with the 3q13.31 microdeletion syndrome. The 2.06 Mb deletion overlapped two microRNAs and seven RefSeq genes, including GAP43, LSAMP, DRD3, and ZBTB20. No overlapping 3q13.31 deletions or duplications were identified in control subjects. Conclusions Later-onset conditions like schizophrenia are increasingly associated with rare copy number variations and associated genomic disorders like the 3q13.31 microdeletion syndrome. Detailed phenotype information across the lifespan facilitates genotype-phenotype correlations, accurate genetic counselling, and anticipatory care.
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Affiliation(s)
| | | | | | | | | | | | | | - Anne S Bassett
- Clinical Genetics Research Program, Centre for Addiction and Mental Health, Toronto, ON, Canada.
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Neurodevelopmental and neuropsychiatric disorders represent an interconnected molecular system. Mol Psychiatry 2014; 19:294-301. [PMID: 23439483 DOI: 10.1038/mp.2013.16] [Citation(s) in RCA: 160] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/04/2012] [Revised: 12/14/2012] [Accepted: 01/02/2013] [Indexed: 12/18/2022]
Abstract
Many putative genetic factors that confer risk to neurodevelopmental disorders such as autism spectrum disorders (ASDs) and X-linked intellectual disability (XLID), and to neuropsychiatric disorders including attention deficit hyperactivity disorder (ADHD) and schizophrenia (SZ) have been identified in individuals from diverse human populations. Although there is significant aetiological heterogeneity within and between these conditions, recent data show that genetic factors contribute to their comorbidity. Many studies have identified candidate gene associations for these mental health disorders, albeit this is often done in a piecemeal fashion with little regard to the inherent molecular complexity. Here, we sought to abstract relationships from our knowledge of systems level biology to help understand the unique and common genetic drivers of these conditions. We undertook a global and systematic approach to build and integrate available data in gene networks associated with ASDs, XLID, ADHD and SZ. Complex network concepts and computational methods were used to investigate whether candidate genes associated with these conditions were related through mechanisms of gene regulation, functional protein-protein interactions, transcription factor (TF) and microRNA (miRNA) binding sites. Although our analyses show that genetic variations associated with the four disorders can occur in the same molecular pathways and functional domains, including synaptic transmission, there are patterns of variation that define significant differences between disorders. Of particular interest is DNA variations located in intergenic regions that comprise regulatory sites for TFs or miRNA. Our approach provides a hypothetical framework, which will help discovery and analysis of candidate genes associated with neurodevelopmental and neuropsychiatric disorders.
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Purcell SM, Moran JL, Fromer M, Ruderfer D, Solovieff N, Roussos P, O’Dushlaine C, Chambert K, Bergen SE, Kähler A, Duncan L, Stahl E, Genovese G, Fernández E, Collins MO, Komiyama NH, Choudhary JS, Magnusson PKE, Banks E, Shakir K, Garimella K, Fennell T, de Pristo M, Grant SG, Haggarty S, Gabriel S, Scolnick EM, Lander ES, Hultman C, Sullivan PF, McCarroll SA, Sklar P. A polygenic burden of rare disruptive mutations in schizophrenia. Nature 2014; 506:185-90. [PMID: 24463508 PMCID: PMC4136494 DOI: 10.1038/nature12975] [Citation(s) in RCA: 1020] [Impact Index Per Article: 102.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2013] [Accepted: 12/24/2013] [Indexed: 12/11/2022]
Abstract
Schizophrenia is a common disease with a complex aetiology, probably involving multiple and heterogeneous genetic factors. Here, by analysing the exome sequences of 2,536 schizophrenia cases and 2,543 controls, we demonstrate a polygenic burden primarily arising from rare (less than 1 in 10,000), disruptive mutations distributed across many genes. Particularly enriched gene sets include the voltage-gated calcium ion channel and the signalling complex formed by the activity-regulated cytoskeleton-associated scaffold protein (ARC) of the postsynaptic density, sets previously implicated by genome-wide association and copy-number variation studies. Similar to reports in autism, targets of the fragile X mental retardation protein (FMRP, product of FMR1) are enriched for case mutations. No individual gene-based test achieves significance after correction for multiple testing and we do not detect any alleles of moderately low frequency (approximately 0.5 to 1 per cent) and moderately large effect. Taken together, these data suggest that population-based exome sequencing can discover risk alleles and complements established gene-mapping paradigms in neuropsychiatric disease.
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Affiliation(s)
- Shaun M. Purcell
- Stanley Center for Psychiatric Research, Broad Institute of MIT & Harvard, Cambridge, MA, 02142, USA
- Division of Psychiatric Genomics in the Department of Psychiatry, and Institute for Genomics and Multiscale Biology, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA
- Analytic and Translational Genetics Unit, Psychiatric and Neurodevelopmental Genetics Unit, Massachusetts General Hospital, Boston, MA, 02114, USA
- Medical & Population Genetics Program, Broad Institute of MIT & Harvard, Cambridge, MA, 02142, USA
| | - Jennifer L. Moran
- Stanley Center for Psychiatric Research, Broad Institute of MIT & Harvard, Cambridge, MA, 02142, USA
| | - Menachem Fromer
- Stanley Center for Psychiatric Research, Broad Institute of MIT & Harvard, Cambridge, MA, 02142, USA
- Division of Psychiatric Genomics in the Department of Psychiatry, and Institute for Genomics and Multiscale Biology, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA
- Analytic and Translational Genetics Unit, Psychiatric and Neurodevelopmental Genetics Unit, Massachusetts General Hospital, Boston, MA, 02114, USA
| | - Douglas Ruderfer
- Division of Psychiatric Genomics in the Department of Psychiatry, and Institute for Genomics and Multiscale Biology, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA
| | - Nadia Solovieff
- Analytic and Translational Genetics Unit, Psychiatric and Neurodevelopmental Genetics Unit, Massachusetts General Hospital, Boston, MA, 02114, USA
| | - Panos Roussos
- Division of Psychiatric Genomics in the Department of Psychiatry, and Institute for Genomics and Multiscale Biology, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA
| | - Colm O’Dushlaine
- Stanley Center for Psychiatric Research, Broad Institute of MIT & Harvard, Cambridge, MA, 02142, USA
| | - Kimberly Chambert
- Stanley Center for Psychiatric Research, Broad Institute of MIT & Harvard, Cambridge, MA, 02142, USA
| | - Sarah E. Bergen
- Stanley Center for Psychiatric Research, Broad Institute of MIT & Harvard, Cambridge, MA, 02142, USA
- Department of Medical Epidemiology and Biostatisics, Karolinska Institutet, Stockholm, SE-171 77, Sweden
| | - Anna Kähler
- Department of Medical Epidemiology and Biostatisics, Karolinska Institutet, Stockholm, SE-171 77, Sweden
| | - Laramie Duncan
- Analytic and Translational Genetics Unit, Psychiatric and Neurodevelopmental Genetics Unit, Massachusetts General Hospital, Boston, MA, 02114, USA
| | - Eli Stahl
- Division of Psychiatric Genomics in the Department of Psychiatry, and Institute for Genomics and Multiscale Biology, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA
| | - Giulio Genovese
- Stanley Center for Psychiatric Research, Broad Institute of MIT & Harvard, Cambridge, MA, 02142, USA
| | - Esperanza Fernández
- Center for Human Genetics, KU Leuven, 3000 Leuven, Belgium; VIB Center for Biology of Disease, 3000 Leuven, Belgium
| | - Mark O Collins
- Proteomic Mass Spectrometry, The Wellcome Trust Sanger Institute, Cambridge, UK
| | - Noboru H. Komiyama
- Proteomic Mass Spectrometry, The Wellcome Trust Sanger Institute, Cambridge, UK
| | - Jyoti S. Choudhary
- Proteomic Mass Spectrometry, The Wellcome Trust Sanger Institute, Cambridge, UK
| | - Patrik K. E. Magnusson
- Department of Medical Epidemiology and Biostatisics, Karolinska Institutet, Stockholm, SE-171 77, Sweden
| | - Eric Banks
- Medical & Population Genetics Program, Broad Institute of MIT & Harvard, Cambridge, MA, 02142, USA
| | - Khalid Shakir
- Medical & Population Genetics Program, Broad Institute of MIT & Harvard, Cambridge, MA, 02142, USA
| | - Kiran Garimella
- Medical & Population Genetics Program, Broad Institute of MIT & Harvard, Cambridge, MA, 02142, USA
| | - Tim Fennell
- Medical & Population Genetics Program, Broad Institute of MIT & Harvard, Cambridge, MA, 02142, USA
| | - Mark de Pristo
- Medical & Population Genetics Program, Broad Institute of MIT & Harvard, Cambridge, MA, 02142, USA
| | - Seth G.N. Grant
- Genes to Cognition Programme, Centre for Clinical Brain Sciences and Centre for Neuroregeneration, The University of Edinburgh, Edinburgh, UK
| | - Stephen Haggarty
- Stanley Center for Psychiatric Research, Broad Institute of MIT & Harvard, Cambridge, MA, 02142, USA
- Analytic and Translational Genetics Unit, Psychiatric and Neurodevelopmental Genetics Unit, Massachusetts General Hospital, Boston, MA, 02114, USA
- Department of Neurology, Harvard Medical School, Massachusetts General Hospital, Boston, MA, 02114, USA
| | - Stacey Gabriel
- Medical & Population Genetics Program, Broad Institute of MIT & Harvard, Cambridge, MA, 02142, USA
| | - Edward M. Scolnick
- Stanley Center for Psychiatric Research, Broad Institute of MIT & Harvard, Cambridge, MA, 02142, USA
| | - Eric S. Lander
- Medical & Population Genetics Program, Broad Institute of MIT & Harvard, Cambridge, MA, 02142, USA
| | - Christina Hultman
- Department of Medical Epidemiology and Biostatisics, Karolinska Institutet, Stockholm, SE-171 77, Sweden
| | - Patrick F. Sullivan
- Department of Genetics, University of North Carolina, CB# 7264, Chapel Hill, NC, 27599-7264, USA
| | - Steven A. McCarroll
- Stanley Center for Psychiatric Research, Broad Institute of MIT & Harvard, Cambridge, MA, 02142, USA
- Medical & Population Genetics Program, Broad Institute of MIT & Harvard, Cambridge, MA, 02142, USA
- Department of Genetics, Harvard Medical School, Boston, MA, 02115, USA
| | - Pamela Sklar
- Division of Psychiatric Genomics in the Department of Psychiatry, and Institute for Genomics and Multiscale Biology, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA
- Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA
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Costain G, Esplen MJ, Toner B, Scherer SW, Meschino WS, Hodgkinson KA, Bassett AS. Evaluating genetic counseling for individuals with schizophrenia in the molecular age. Schizophr Bull 2014; 40:78-87. [PMID: 23236078 PMCID: PMC3885288 DOI: 10.1093/schbul/sbs138] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
BACKGROUND Recent advances in schizophrenia genetics are shedding new light on etiopathogenesis, but issues germane to translation of findings into clinical practice are relatively understudied. We assessed the need for, and efficacy of, a contemporary genetic counseling protocol for individuals with schizophrenia. METHODS After characterizing rare copy number variation in a cohort of adults with schizophrenia, we recruited subjects from the majority of individuals who had no clinically relevant structural genetic variant. We used a pre-post study design with longitudinal follow-up to assess both the profile of need and the impact of general genetic counseling on key knowledge-based and psychological factors. RESULTS Thirty-nine (60.0%) of 65 patients approached actively expressed an interest in the study. At baseline, participants (n = 25) tended to overestimate the risk of familial recurrence of schizophrenia, express considerable concern related to this perceived risk, endorse myths about schizophrenia etiology, and blame themselves for their illness. Postcounseling, there was a significant improvement in understanding of the empiric recurrence risk (P = .0090), accompanied by a decrease in associated concern (P = .0020). There were also significant gains in subjective (P = .0007) and objective (P = .0103) knowledge, and reductions in internalized stigma (P = .0111) and self-blame (P = .0401). Satisfaction with genetic counseling, including endorsement of the need for such counseling (86.4%), was high. CONCLUSIONS These results provide initial evidence of need for, and efficacy of, genetic counseling for individuals with schizophrenia. The findings may help facilitate development of a contemporary genetic counseling process that could optimize outcomes in the nascent field of evidence-based psychiatric genetic counseling.
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Affiliation(s)
- Gregory Costain
- To whom correspondence should be addressed; 33 Russell Street, Room 1100, Toronto, Ontario, Canada M5S 2S1; tel: (416) 535-8501 x2731, fax: (416) 535-7199, e-mail:
| | - Mary Jane Esplen
- Department of Psychiatry, University of Toronto, Toronto, Ontario, Canada;,Behavioural Sciences and Health Research Division, Toronto General Hospital, University Health Network, Toronto, Ontario, Canada
| | - Brenda Toner
- Institute of Medical Science, University of Toronto, Toronto, Ontario, Canada;,Department of Psychiatry, University of Toronto, Toronto, Ontario, Canada;,Social Equity and Health Research, Centre for Addiction and Mental Health, Toronto, Ontario, Canada
| | - Stephen W. Scherer
- The Centre for Applied Genomics and Program in Genetics and Genome Biology, The Hospital for Sick Children, Toronto, Ontario, Canada;,Department of Molecular Genetics and the McLaughlin Centre, University of Toronto, Toronto, Ontario, Canada
| | - Wendy S. Meschino
- Department of Genetics, North York General Hospital, North York, Ontario, Canada
| | - Kathleen A. Hodgkinson
- Clinical Epidemiology and Genetics, Faculty of Medicine, Memorial University of Newfoundland and Labrador, St John’s, Newfoundland, Canada
| | - Anne S. Bassett
- Clinical Genetics Research Program, Centre for Addiction and Mental Health, Toronto, Ontario, Canada;,Institute of Medical Science, University of Toronto, Toronto, Ontario, Canada;,Department of Psychiatry, University of Toronto, Toronto, Ontario, Canada;,Department of Psychiatry and Division of Cardiology, Department of Medicine, University Health Network, Toronto, Ontario, Canada,To whom correspondence should be addressed; 33 Russell Street, Room 1100, Toronto, Ontario, Canada M5S 2S1; tel: (416) 535–8501 x2731, fax: (416) 535–7199, e-mail:
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