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Takada S, Weitering TJ, van Os NJH, Du L, Pico-Knijnenburg I, Kuipers TB, Mei H, Salzer E, Willemsen MAAP, Weemaes CMR, Pan-Hammarstrom Q, van der Burg M. Causative mechanisms and clinical impact of immunoglobulin deficiencies in ataxia telangiectasia. J Allergy Clin Immunol 2024; 153:1392-1405. [PMID: 38280573 DOI: 10.1016/j.jaci.2023.12.029] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2023] [Revised: 12/07/2023] [Accepted: 12/19/2023] [Indexed: 01/29/2024]
Abstract
BACKGROUND Ataxia telangiectasia (AT) is characterized by cerebellar ataxia, telangiectasia, immunodeficiency, and increased cancer susceptibility and is caused by mutations in the ataxia telangiectasia mutated (ATM) gene. The immunodeficiency comprises predominantly immunoglobulin deficiency, mainly IgA and IgG2, with a variable severity. So far, the exact mechanisms underlying the immunoglobulin deficiency, especially the variable severity, remain unelucidated. OBJECTIVE We characterized the clinical impact of immunoglobulin deficiencies in AT and elucidated their mechanisms in AT. METHODS We analyzed long-term immunoglobulin levels, immunophenotyping, and survival time in our cohort (n = 87, median age 16 years; maximum 64 years). Somatic hypermutation and class-switch junctions in B cells were analyzed by next-generation sequencing. Furthermore, an in vitro class-switching induction assay was performed, followed by RNA sequencing, to assess the effect of ATM inhibition. RESULTS Only the hyper-IgM AT phenotype significantly worsened survival time, while IgA or IgG2 deficiencies did not. The immunoglobulin levels showed predominantly decreased IgG2 and IgA. Moreover, flow cytometric analysis demonstrated reduced naive B and T lymphocytes and a deficiency of class-switched IgG2 and IgA memory B cells. Somatic hypermutation frequencies were lowered in IgA- and IgG2-deficient patients, indicating hampered germinal center reaction. In addition, the microhomology of switch junctions was elongated, suggesting alternative end joining during class-switch DNA repair. The in vitro class switching and proliferation were negatively affected by ATM inhibition. RNA sequencing analysis showed that ATM inhibitor influenced expression of germinal center reaction genes. CONCLUSION Immunoglobulin deficiency in AT is caused by disturbed development of class-switched memory B cells. ATM deficiency affects both germinal center reaction and choice of DNA-repair pathway in class switching.
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Affiliation(s)
- Sanami Takada
- Department of Pediatrics, Laboratory for Pediatric Immunology, Willem-Alexander Children's Hospital, Leiden University Medical Center, Leiden, The Netherlands
| | - Thomas J Weitering
- Department of Pediatrics, Laboratory for Pediatric Immunology, Willem-Alexander Children's Hospital, Leiden University Medical Center, Leiden, The Netherlands
| | - Nienke J H van Os
- Department of Pediatric Neurology, Amalia Children's Hospital, Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center, Nijmegen, The Netherlands; Department of Neurology, Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Likun Du
- Department of Biosciences and Nutrition, Karolinska Institute, Stockholm, Sweden
| | - Ingrid Pico-Knijnenburg
- Department of Pediatrics, Laboratory for Pediatric Immunology, Willem-Alexander Children's Hospital, Leiden University Medical Center, Leiden, The Netherlands
| | - Thomas B Kuipers
- Sequencing Analysis Support Core Department of Biomedical Data Sciences, Leiden University Medical Center, Leiden, The Netherlands
| | - Hailiang Mei
- Sequencing Analysis Support Core Department of Biomedical Data Sciences, Leiden University Medical Center, Leiden, The Netherlands
| | - Elisabeth Salzer
- Department of Pediatrics, Laboratory for Pediatric Immunology, Willem-Alexander Children's Hospital, Leiden University Medical Center, Leiden, The Netherlands
| | - Michèl A A P Willemsen
- Department of Pediatric Neurology, Amalia Children's Hospital, Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Corry M R Weemaes
- Department of Pediatrics, Amalia Children's Hospital, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Qiang Pan-Hammarstrom
- Department of Neurology, Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Mirjam van der Burg
- Department of Pediatrics, Laboratory for Pediatric Immunology, Willem-Alexander Children's Hospital, Leiden University Medical Center, Leiden, The Netherlands.
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2
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Calame DG, Guo T, Wang C, Garrett L, Jolly A, Dawood M, Kurolap A, Henig NZ, Fatih JM, Herman I, Du H, Mitani T, Becker L, Rathkolb B, Gerlini R, Seisenberger C, Marschall S, Hunter JV, Gerard A, Heidlebaugh A, Challman T, Spillmann RC, Jhangiani SN, Coban-Akdemir Z, Lalani S, Liu L, Revah-Politi A, Iglesias A, Guzman E, Baugh E, Boddaert N, Rondeau S, Ormieres C, Barcia G, Tan QKG, Thiffault I, Pastinen T, Sheikh K, Biliciler S, Mei D, Melani F, Shashi V, Yaron Y, Steele M, Wakeling E, Østergaard E, Nazaryan-Petersen L, Millan F, Santiago-Sim T, Thevenon J, Bruel AL, Thauvin-Robinet C, Popp D, Platzer K, Gawlinski P, Wiszniewski W, Marafi D, Pehlivan D, Posey JE, Gibbs RA, Gailus-Durner V, Guerrini R, Fuchs H, Hrabě de Angelis M, Hölter SM, Cheung HH, Gu S, Lupski JR. Monoallelic variation in DHX9, the gene encoding the DExH-box helicase DHX9, underlies neurodevelopment disorders and Charcot-Marie-Tooth disease. Am J Hum Genet 2023; 110:1394-1413. [PMID: 37467750 PMCID: PMC10432148 DOI: 10.1016/j.ajhg.2023.06.013] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2023] [Revised: 06/23/2023] [Accepted: 06/27/2023] [Indexed: 07/21/2023] Open
Abstract
DExD/H-box RNA helicases (DDX/DHX) are encoded by a large paralogous gene family; in a subset of these human helicase genes, pathogenic variation causes neurodevelopmental disorder (NDD) traits and cancer. DHX9 encodes a BRCA1-interacting nuclear helicase regulating transcription, R-loops, and homologous recombination and exhibits the highest mutational constraint of all DDX/DHX paralogs but remains unassociated with disease traits in OMIM. Using exome sequencing and family-based rare-variant analyses, we identified 20 individuals with de novo, ultra-rare, heterozygous missense or loss-of-function (LoF) DHX9 variant alleles. Phenotypes ranged from NDDs to the distal symmetric polyneuropathy axonal Charcot-Marie-Tooth disease (CMT2). Quantitative Human Phenotype Ontology (HPO) analysis demonstrated genotype-phenotype correlations with LoF variants causing mild NDD phenotypes and nuclear localization signal (NLS) missense variants causing severe NDD. We investigated DHX9 variant-associated cellular phenotypes in human cell lines. Whereas wild-type DHX9 was restricted to the nucleus, NLS missense variants abnormally accumulated in the cytoplasm. Fibroblasts from an individual with an NLS variant also showed abnormal cytoplasmic DHX9 accumulation. CMT2-associated missense variants caused aberrant nucleolar DHX9 accumulation, a phenomenon previously associated with cellular stress. Two NDD-associated variants, p.Gly411Glu and p.Arg761Gln, altered DHX9 ATPase activity. The severe NDD-associated variant p.Arg141Gln did not affect DHX9 localization but instead increased R-loop levels and double-stranded DNA breaks. Dhx9-/- mice exhibited hypoactivity in novel environments, tremor, and sensorineural hearing loss. All together, these results establish DHX9 as a critical regulator of mammalian neurodevelopment and neuronal homeostasis.
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Affiliation(s)
- Daniel G Calame
- Section of Pediatric Neurology and Developmental Neuroscience, Department of Pediatrics, Baylor College of Medicine, Houston, TX, USA; Texas Children's Hospital, Houston, TX, USA; Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, USA
| | - Tianyu Guo
- School of Biomedical Sciences, Faculty of Medicine, the Chinese University of Hong Kong, Hong Kong SAR, China
| | - Chen Wang
- School of Biomedical Sciences, Faculty of Medicine, the Chinese University of Hong Kong, Hong Kong SAR, China
| | - Lillian Garrett
- Institute of Experimental Genetics and German Mouse Clinic, Helmholtz Zentrum München, German Research Center for Environmental Health, Neuherberg, Germany; Institute of Developmental Genetics, Helmholtz Zentrum München, German Research Center for Environmental Health, Neuherberg, Germany
| | - Angad Jolly
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, USA; Medical Scientist Training Program, Baylor College of Medicine, Houston, TX, USA
| | - Moez Dawood
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, USA; Medical Scientist Training Program, Baylor College of Medicine, Houston, TX, USA; Human Genome Sequencing Center, Baylor College of Medicine, Houston, TX, USA
| | - Alina Kurolap
- Genetics Institute and Genomics Center, Tel Aviv Sourasky Medical Center, Tel Aviv, Israel
| | - Noa Zunz Henig
- Genetics Institute and Genomics Center, Tel Aviv Sourasky Medical Center, Tel Aviv, Israel
| | - Jawid M Fatih
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, USA
| | - Isabella Herman
- Section of Pediatric Neurology and Developmental Neuroscience, Department of Pediatrics, Baylor College of Medicine, Houston, TX, USA; Texas Children's Hospital, Houston, TX, USA; Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, USA; Boys Town National Research Hospital, Boys Town, NE, USA
| | - Haowei Du
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, USA
| | - Tadahiro Mitani
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, USA
| | - Lore Becker
- Institute of Experimental Genetics and German Mouse Clinic, Helmholtz Zentrum München, German Research Center for Environmental Health, Neuherberg, Germany
| | - Birgit Rathkolb
- Institute of Experimental Genetics and German Mouse Clinic, Helmholtz Zentrum München, German Research Center for Environmental Health, Neuherberg, Germany; Institute of Molecular Animal Breeding and Biotechnology, Gene Center, Ludwig-Maximilians University Munich, Munich, Germany; German Center for Diabetes Research (DZD), Ingolstädter Landstr. 1, 85764 Neuherberg, Germany
| | - Raffaele Gerlini
- Institute of Experimental Genetics and German Mouse Clinic, Helmholtz Zentrum München, German Research Center for Environmental Health, Neuherberg, Germany
| | - Claudia Seisenberger
- Institute of Experimental Genetics and German Mouse Clinic, Helmholtz Zentrum München, German Research Center for Environmental Health, Neuherberg, Germany
| | - Susan Marschall
- Institute of Experimental Genetics and German Mouse Clinic, Helmholtz Zentrum München, German Research Center for Environmental Health, Neuherberg, Germany
| | - Jill V Hunter
- Department of Radiology, Baylor College of Medicine, Houston, TX, USA; E.B. Singleton Department of Pediatric Radiology, Texas Children's Hospital, Houston, TX, USA
| | - Amanda Gerard
- Texas Children's Hospital, Houston, TX, USA; Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, USA
| | | | - Thomas Challman
- Autism & Developmental Medicine Institute, Geisinger, Danville, PA, USA
| | - Rebecca C Spillmann
- Department of Pediatrics, Duke University Medical Center, Duke University, Durham, NC, USA
| | - Shalini N Jhangiani
- Human Genome Sequencing Center, Baylor College of Medicine, Houston, TX, USA
| | - Zeynep Coban-Akdemir
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, USA; Human Genetics Center, Department of Epidemiology, Human Genetics, and Environmental Sciences, School of Public Health, University of Texas Health Science Center at Houston, Houston, TX, USA
| | - Seema Lalani
- Texas Children's Hospital, Houston, TX, USA; Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, USA
| | - Lingxiao Liu
- School of Biomedical Sciences, Faculty of Medicine, the Chinese University of Hong Kong, Hong Kong SAR, China
| | - Anya Revah-Politi
- Institute for Genomic Medicine, Columbia University Irving Medical Center, New York, NY, USA; Department of Pathology and Cell Biology, Columbia University Irving Medical Center, New York, NY, USA
| | - Alejandro Iglesias
- Division of Clinical Genetics, Department of Pediatrics, Columbia University Irving Medical Center, New York, NY, USA
| | - Edwin Guzman
- Division of Clinical Genetics, Department of Pediatrics, Columbia University Irving Medical Center, New York, NY, USA
| | - Evan Baugh
- Institute for Genomic Medicine, Columbia University Irving Medical Center, New York, NY, USA
| | - Nathalie Boddaert
- Paediatric Radiology Department, AP-HP, Hôpital Necker Enfants Malades, Université Paris Cité, Institut Imagine INSERM U1163, 75015 Paris, France
| | - Sophie Rondeau
- Service de Médecine Génomique des Maladies Rares - APHP, Hôpital Necker Enfants Malades, Université de Paris, Paris, France
| | - Clothide Ormieres
- Service de Médecine Génomique des Maladies Rares - APHP, Hôpital Necker Enfants Malades, Université de Paris, Paris, France
| | - Giulia Barcia
- Service de Médecine Génomique des Maladies Rares - APHP, Hôpital Necker Enfants Malades, Université de Paris, Paris, France
| | - Queenie K G Tan
- Department of Pediatrics, Duke University Medical Center, Duke University, Durham, NC, USA
| | - Isabelle Thiffault
- Genomic Medicine Center, Children's Mercy Hospital, Kansas City, MO, USA
| | - Tomi Pastinen
- Genomic Medicine Center, Children's Mercy Hospital, Kansas City, MO, USA; University of Missouri Kansas City School of Medicine, Kansas City, MO, USA
| | - Kazim Sheikh
- Department of Neurology, UT Health Science Center at Houston, McGovern Medical School, Houston, TX, USA
| | - Suur Biliciler
- Department of Neurology, UT Health Science Center at Houston, McGovern Medical School, Houston, TX, USA
| | - Davide Mei
- Neuroscience Department, Meyer Children's Hospital IRCCS, Florence, Italy
| | - Federico Melani
- Neuroscience Department, Meyer Children's Hospital IRCCS, Florence, Italy
| | - Vandana Shashi
- Department of Pediatrics, Duke University Medical Center, Duke University, Durham, NC, USA
| | - Yuval Yaron
- Genetics Institute and Genomics Center, Tel Aviv Sourasky Medical Center, Tel Aviv, Israel; Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Mary Steele
- Lifetime Neurodevelopmental Care, San Francisco, CA, USA
| | - Emma Wakeling
- North East Thames Regional Genetic Service, Great Ormond Street Hospital for Children NHS Foundation Trust, London, UK
| | - Elsebet Østergaard
- Department of Clinical Genetics, Rigshospitalet, Copenhagen University Hospital, Copenhagen, Denmark; Department of Clinical Medicine, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Lusine Nazaryan-Petersen
- Department of Clinical Genetics, Rigshospitalet, Copenhagen University Hospital, Copenhagen, Denmark; Department of Cellular and Molecular Medicine, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | | | | | - Julien Thevenon
- Centre de Génétique et Centre de Référence Anomalies du Développement et Syndromes Malformatifs de l'Interrégion Est, Fédération Hospitalo-Universitaire Médecine TRANSLationnelle et Anomalies du Développement, Centre Hospitalier Universitaire Dijon, Equipe Genetics of Developmental Anomalies-INSERM UMR 1231, Dijon, France
| | - Ange-Line Bruel
- Functional Unit for Diagnostic Innovation in Rare Diseases, FHU-TRANSLAD, Dijon Bourgogne University Hospital, Dijon, France; INSERM UMR1231 GAD "Génétique des Anomalies du Développement," FHU-TRANSLAD, University of Burgundy, Dijon, France
| | - Christel Thauvin-Robinet
- INSERM UMR1231 GAD "Génétique des Anomalies du Développement," FHU-TRANSLAD, University of Burgundy, Dijon, France; Department of Genetics and Reference Center for Development Disorders and Intellectual Disabilities, Dijon Bourgogne University Hospital, Dijon, France
| | - Denny Popp
- Institute of Human Genetics, University of Leipzig Medical Center, Leipzig, Germany
| | - Konrad Platzer
- Institute of Human Genetics, University of Leipzig Medical Center, Leipzig, Germany
| | - Pawel Gawlinski
- Institute of Mother and Child, Kasprzaka 17a, 02-211 Warsaw, Poland
| | - Wojciech Wiszniewski
- Oregon Health & Sciences University, 3181 SW Sam Jackson Park Road L103, Portland, OR, USA
| | - Dana Marafi
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, USA; Department of Pediatrics, Faculty of Medicine, Kuwait University, Kuwait City, Kuwait
| | - Davut Pehlivan
- Section of Pediatric Neurology and Developmental Neuroscience, Department of Pediatrics, Baylor College of Medicine, Houston, TX, USA; Texas Children's Hospital, Houston, TX, USA; Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, USA
| | - Jennifer E Posey
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, USA
| | - Richard A Gibbs
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, USA; Human Genome Sequencing Center, Baylor College of Medicine, Houston, TX, USA
| | - Valerie Gailus-Durner
- Institute of Experimental Genetics and German Mouse Clinic, Helmholtz Zentrum München, German Research Center for Environmental Health, Neuherberg, Germany
| | - Renzo Guerrini
- Neuroscience Department, Meyer Children's Hospital IRCCS, Florence, Italy; University of Florence, Florence, Italy
| | - Helmut Fuchs
- Institute of Experimental Genetics and German Mouse Clinic, Helmholtz Zentrum München, German Research Center for Environmental Health, Neuherberg, Germany
| | - Martin Hrabě de Angelis
- Institute of Experimental Genetics and German Mouse Clinic, Helmholtz Zentrum München, German Research Center for Environmental Health, Neuherberg, Germany; German Center for Diabetes Research (DZD), Ingolstädter Landstr. 1, 85764 Neuherberg, Germany; Chair of Experimental Genetics, TUM School of Life Sciences, Technische Universität München, Alte Akademie 8, 85354 Freising, Germany
| | - Sabine M Hölter
- Institute of Experimental Genetics and German Mouse Clinic, Helmholtz Zentrum München, German Research Center for Environmental Health, Neuherberg, Germany; Institute of Developmental Genetics, Helmholtz Zentrum München, German Research Center for Environmental Health, Neuherberg, Germany; Technische Universität München, Freising-Weihenstephan, Germany
| | - Hoi-Hung Cheung
- School of Biomedical Sciences, Faculty of Medicine, the Chinese University of Hong Kong, Hong Kong SAR, China
| | - Shen Gu
- School of Biomedical Sciences, Faculty of Medicine, the Chinese University of Hong Kong, Hong Kong SAR, China; Key Laboratory for Regenerative Medicine, Ministry of Education, School of Biomedical Sciences, Faculty of Medicine, the Chinese University of Hong Kong, Hong Kong SAR, China; Kunming Institute of Zoology Chinese Academy of Sciences, the Chinese University of Hong Kong Joint Laboratory of Bioresources and Molecular Research of Common Diseases, Hong Kong SAR, China.
| | - James R Lupski
- Texas Children's Hospital, Houston, TX, USA; Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, USA; Human Genome Sequencing Center, Baylor College of Medicine, Houston, TX, USA; Department of Pediatrics, Baylor College of Medicine, Houston, TX, USA.
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Jiang B, Murray C, Cole BL, Glover JNM, Chan GK, Deschenes J, Mani RS, Subedi S, Nerva JD, Wang AC, Lockwood CM, Mefford HC, Leary SES, Ojemann JG, Weinfeld M, Ene CI. Mutations of the DNA repair gene PNKP in a patient with microcephaly, seizures, and developmental delay (MCSZ) presenting with a high-grade brain tumor. Sci Rep 2022; 12:5386. [PMID: 35354845 PMCID: PMC8967877 DOI: 10.1038/s41598-022-09097-w] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2021] [Accepted: 03/04/2022] [Indexed: 11/08/2022] Open
Abstract
Polynucleotide Kinase-Phosphatase (PNKP) is a bifunctional enzyme that possesses both DNA 3'-phosphatase and DNA 5'-kinase activities, which are required for processing termini of single- and double-strand breaks generated by reactive oxygen species (ROS), ionizing radiation and topoisomerase I poisons. Even though PNKP is central to DNA repair, there have been no reports linking PNKP mutations in a Microcephaly, Seizures, and Developmental Delay (MSCZ) patient to cancer. Here, we characterized the biochemical significance of 2 germ-line point mutations in the PNKP gene of a 3-year old male with MSCZ who presented with a high-grade brain tumor (glioblastoma multiforme) within the cerebellum. Functional and biochemical studies demonstrated these PNKP mutations significantly diminished DNA kinase/phosphatase activities, altered its cellular distribution, caused defective repair of DNA single/double stranded breaks, and were associated with a higher propensity for oncogenic transformation. Our findings indicate that specific PNKP mutations may contribute to tumor initiation within susceptible cells in the CNS by limiting DNA damage repair and increasing rates of spontaneous mutations resulting in pediatric glioma associated driver mutations such as ATRX and TP53.
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Affiliation(s)
- Bingcheng Jiang
- Department of Oncology, University of Alberta, Cross Cancer Institute, 11560 University Ave., Edmonton, AB, T6G 1Z2, Canada
| | - Cameron Murray
- Department of Biochemistry, University of Alberta, Medical Sciences Building, Edmonton, AB, T6G 2H7, Canada
| | - Bonnie L Cole
- Department of Pathology, University of Washington, Seattle, WA, USA
| | - J N Mark Glover
- Department of Biochemistry, University of Alberta, Medical Sciences Building, Edmonton, AB, T6G 2H7, Canada
| | - Gordon K Chan
- Department of Oncology, University of Alberta, Cross Cancer Institute, 11560 University Ave., Edmonton, AB, T6G 1Z2, Canada
| | - Jean Deschenes
- Department of Laboratory Medicine and Pathology, University of Alberta, Cross Cancer Institute, 11560 University Ave., Edmonton, AB, T6G 1Z2, Canada
| | - Rajam S Mani
- Department of Oncology, University of Alberta, Cross Cancer Institute, 11560 University Ave., Edmonton, AB, T6G 1Z2, Canada
| | - Sudip Subedi
- Department of Oncology, University of Alberta, Cross Cancer Institute, 11560 University Ave., Edmonton, AB, T6G 1Z2, Canada
| | - John D Nerva
- Department of Neurological Surgery, Tulane University, New Orleans, LA, USA
| | - Anthony C Wang
- Department of Neurological Surgery, University of California Los Angeles, Los Angeles, CA, USA
| | | | - Heather C Mefford
- Division of Genetics Medicine, University of Washington, Seattle, WA, USA
| | - Sarah E S Leary
- Division of Pediatric Hematology/Oncology, Seattle Children's Hospital, Seattle, WA, USA
| | - Jeffery G Ojemann
- Department of Neurological Surgery, University of Washington, Seattle, WA, USA
| | - Michael Weinfeld
- Department of Oncology, University of Alberta, Cross Cancer Institute, 11560 University Ave., Edmonton, AB, T6G 1Z2, Canada.
| | - Chibawanye I Ene
- Department of Neurological Surgery, MD Anderson Cancer Center, Houston, TX, USA.
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