1. Academic Validation
  2. C2orf69 mutations disrupt mitochondrial function and cause a multisystem human disorder with recurring autoinflammation

C2orf69 mutations disrupt mitochondrial function and cause a multisystem human disorder with recurring autoinflammation

  • J Clin Invest. 2021 Jun 15;131(12):e143078. doi: 10.1172/JCI143078.
Eva Lausberg 1 Sebastian Gießelmann 1 Joseph P Dewulf 2 3 Elsa Wiame 2 Anja Holz 4 Ramona Salvarinova 5 6 Clara D van Karnebeek 7 8 Patricia Klemm 9 Kim Ohl 9 Michael Mull 10 Till Braunschweig 11 Joachim Weis 12 Clemens J Sommer 13 Stephanie Demuth 14 Claudia Haase 15 Claudia Stollbrink-Peschgens 9 François-Guillaume Debray 16 Cecile Libioulle 16 Daniela Choukair 17 Prasad T Oommen 18 Arndt Borkhardt 18 Harald Surowy 19 Dagmar Wieczorek 19 Norbert Wagner 9 Robert Meyer 1 Thomas Eggermann 1 Matthias Begemann 1 Emile Van Schaftingen 2 Martin Häusler 9 Klaus Tenbrock 9 Lambert van den Heuvel 20 Miriam Elbracht 1 Ingo Kurth 1 Florian Kraft 1
Affiliations

Affiliations

  • 1 Institute of Human Genetics, Medical Faculty, Rheinisch-Westfaelische Technische Hochschule (RWTH) Aachen University, Aachen, Germany.
  • 2 Laboratory of Physiological Chemistry, de Duve Institute and.
  • 3 Department of Laboratory Medicine, Cliniques Universitaires Saint-Luc, Université Catholique de Louvain, Brussels, Belgium.
  • 4 CeGaT GmbH and Praxis für Humangenetik, Tübingen, Germany.
  • 5 Division of Biochemical Diseases, Department of Pediatrics, British Columbia Children's Hospital Vancouver, Vancouver, British Columbia, Canada.
  • 6 British Columbia Children's Hospital Research Institute, University of British Columbia (UBC), Vancouver, British Columbia, Canada.
  • 7 Department of Pediatrics, Radboud Centre for Mitochondrial Medicine, Radboud University Medical Centre, Nijmegen, Netherlands.
  • 8 Department of Pediatrics, Centre for Molecular Medicine and Therapeutics, UBC, Vancouver, British Columbia, Canada.
  • 9 Department of Pediatrics, Medical Faculty.
  • 10 Department of Diagnostic and Interventional Neuroradiology, Medical Faculty.
  • 11 Institute of Pathology, Medical Faculty, and.
  • 12 Institute of Neuropathology, Medical Faculty, RWTH University, Aachen, Germany.
  • 13 Institute of Neuropathology, University Medical Center of the Johannes Gutenberg University Mainz, Mainz, Germany.
  • 14 Praxis für Humangenetik Erfurt, Erfurt, Germany.
  • 15 HELIOS Klinikum Erfurt, Ambulanz für Angeborene Stoffwechselerkrankungen, Sozialpädiatrisches Zentrum, Erfurt, Germany.
  • 16 Department of Human Genetics, Centre Hospitalier Universitaire (CHU) de Liège, Liège, Belgium.
  • 17 Department of General Pediatrics, University Children's Hospital, Heidelberg University, Heidelberg, Germany.
  • 18 Department of Pediatric Oncology, Hematology, and Clinical Immunology, University Children's Hospital, Medical Faculty and.
  • 19 Institute of Human Genetics, Medical Faculty, Heinrich-Heine University (HHU), Düsseldorf, Germany.
  • 20 Department of Pediatrics, Translational Metabolic Laboratory at the Department of Laboratory Medicine, Radboud University Medical Center, Nijmegen, Netherlands.
Abstract

BACKGROUNDDeciphering the function of the many genes previously classified as uncharacterized open reading frame (ORF) would complete our understanding of a cell's function and its pathophysiology.METHODSWhole-exome sequencing, yeast 2-hybrid and transcriptome analyses, and molecular characterization were performed in this study to uncover the function of the C2orf69 gene.RESULTSWe identified loss-of-function mutations in the uncharacterized C2orf69 gene in 8 individuals with brain abnormalities involving hypomyelination and microcephaly, liver dysfunction, and recurrent autoinflammation. C2orf69 contains an N-terminal signal peptide that is required and sufficient for mitochondrial localization. Consistent with mitochondrial dysfunction, the patients showed signs of respiratory chain defects, and a CRISPR/Cas9-KO cell model of C2orf69 had similar respiratory chain defects. Patient-derived cells revealed alterations in immunological signaling pathways. Deposits of periodic acid-Schiff-positive (PAS-positive) material in tissues from affected individuals, together with decreased glycogen branching Enzyme 1 (GBE1) activity, indicated an additional impact of C2orf69 on glycogen metabolism.CONCLUSIONSOur study identifies C2orf69 as an important regulator of human mitochondrial function and suggests that this gene has additional influence on other metabolic pathways.

Keywords

Genetic diseases; Genetics; Mitochondria; Neurological disorders.

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