title: Recessive truncating IGHMBP2 mutations presenting as axonal sensorimotor neuropathy.
abstract: OBJECTIVE
  To identify the cause of sensorimotor neuropathy in a cohort of patients with genetically unsolved neuropathies (57 families with a total of 74 members) in whom hitherto known disease genes had been excluded.
  
  
  METHODS
  We used autozygosity mapping or haplotype analysis to delineate potential disease loci in informative families. For mutation detection, we used either whole-exome sequencing or Sanger sequencing of positional candidates. Subsequently, a larger cohort was specifically screened for IGHMBP2 mutations. The pathogenicity of a splice-site mutation was verified in cultured patient skin fibroblasts on the messenger RNA level and by Western blot.
  
  
  RESULTS
  We report on 5 patients with neuropathy from 3 families who carried truncating mutations in IGHMBP2. Contrary to the "classic" phenotype, they did not manifest with respiratory distress, but with progressive sensorimotor neuropathy. Only one patient required nocturnal mask ventilation, while 4 others maintained normal respiratory function by the age of 14, 18, 22, and 37 years. Three patients were still able to walk independently. All patients had a predominantly axonal sensorimotor neuropathy with subsequent muscle atrophy, but without obvious sensory symptoms. Two patients had signs of autonomic neuropathy.
  
  
  CONCLUSIONS
  Mutations in IGHMBP2 should be considered in the molecular genetic workup of patients with hereditary sensorimotor neuropathies, even in the absence of respiratory symptoms.
authors.affiliation: From the Department of Neuropediatrics and the NeuroCure Clinical Research Center (G.S., E.K., S.M.G., E.G., F.S., M.S.), and Department of Neuropediatrics/SPZ (K.v.A.), Charité-Universitätsmedizin Berlin, Germany; Department of Paediatric Neurology-Neuromuscular Service (H.J.), Evelina Children's Hospital, St Thomas' Hospital, the Randall Division of Cell and Molecular Biophysics, Muscle Signalling Section and the Department of Clinical Neuroscience, IoP, King's College, London, UK; Department of Neuropediatrics, Developmental Neurology and Social Pediatrics (U.S.), University of Essen, Germany; Department of Neurology (F.N.), King's College Hospital, London; Department of Clinical Genetics (C.D.), Guy's Hospital, London, UK; and Friedrich Baur Institute (J.S.), Department of Neurology, Ludwig Maximilians University Munich, Germany.
authors.forename: Gudrun
authors.initials: G
authors.lastname: Schottmann
authors.affiliation: From the Department of Neuropediatrics and the NeuroCure Clinical Research Center (G.S., E.K., S.M.G., E.G., F.S., M.S.), and Department of Neuropediatrics/SPZ (K.v.A.), Charité-Universitätsmedizin Berlin, Germany; Department of Paediatric Neurology-Neuromuscular Service (H.J.), Evelina Children's Hospital, St Thomas' Hospital, the Randall Division of Cell and Molecular Biophysics, Muscle Signalling Section and the Department of Clinical Neuroscience, IoP, King's College, London, UK; Department of Neuropediatrics, Developmental Neurology and Social Pediatrics (U.S.), University of Essen, Germany; Department of Neurology (F.N.), King's College Hospital, London; Department of Clinical Genetics (C.D.), Guy's Hospital, London, UK; and Friedrich Baur Institute (J.S.), Department of Neurology, Ludwig Maximilians University Munich, Germany.
authors.forename: Heinz
authors.initials: H
authors.lastname: Jungbluth
authors.affiliation: From the Department of Neuropediatrics and the NeuroCure Clinical Research Center (G.S., E.K., S.M.G., E.G., F.S., M.S.), and Department of Neuropediatrics/SPZ (K.v.A.), Charité-Universitätsmedizin Berlin, Germany; Department of Paediatric Neurology-Neuromuscular Service (H.J.), Evelina Children's Hospital, St Thomas' Hospital, the Randall Division of Cell and Molecular Biophysics, Muscle Signalling Section and the Department of Clinical Neuroscience, IoP, King's College, London, UK; Department of Neuropediatrics, Developmental Neurology and Social Pediatrics (U.S.), University of Essen, Germany; Department of Neurology (F.N.), King's College Hospital, London; Department of Clinical Genetics (C.D.), Guy's Hospital, London, UK; and Friedrich Baur Institute (J.S.), Department of Neurology, Ludwig Maximilians University Munich, Germany.
authors.forename: Ulrike
authors.initials: U
authors.lastname: Schara
authors.affiliation: From the Department of Neuropediatrics and the NeuroCure Clinical Research Center (G.S., E.K., S.M.G., E.G., F.S., M.S.), and Department of Neuropediatrics/SPZ (K.v.A.), Charité-Universitätsmedizin Berlin, Germany; Department of Paediatric Neurology-Neuromuscular Service (H.J.), Evelina Children's Hospital, St Thomas' Hospital, the Randall Division of Cell and Molecular Biophysics, Muscle Signalling Section and the Department of Clinical Neuroscience, IoP, King's College, London, UK; Department of Neuropediatrics, Developmental Neurology and Social Pediatrics (U.S.), University of Essen, Germany; Department of Neurology (F.N.), King's College Hospital, London; Department of Clinical Genetics (C.D.), Guy's Hospital, London, UK; and Friedrich Baur Institute (J.S.), Department of Neurology, Ludwig Maximilians University Munich, Germany.
authors.forename: Ellen
authors.initials: E
authors.lastname: Knierim
authors.affiliation: From the Department of Neuropediatrics and the NeuroCure Clinical Research Center (G.S., E.K., S.M.G., E.G., F.S., M.S.), and Department of Neuropediatrics/SPZ (K.v.A.), Charité-Universitätsmedizin Berlin, Germany; Department of Paediatric Neurology-Neuromuscular Service (H.J.), Evelina Children's Hospital, St Thomas' Hospital, the Randall Division of Cell and Molecular Biophysics, Muscle Signalling Section and the Department of Clinical Neuroscience, IoP, King's College, London, UK; Department of Neuropediatrics, Developmental Neurology and Social Pediatrics (U.S.), University of Essen, Germany; Department of Neurology (F.N.), King's College Hospital, London; Department of Clinical Genetics (C.D.), Guy's Hospital, London, UK; and Friedrich Baur Institute (J.S.), Department of Neurology, Ludwig Maximilians University Munich, Germany.
authors.forename: Susanne
authors.initials: S
authors.lastname: Morales Gonzalez
authors.affiliation: From the Department of Neuropediatrics and the NeuroCure Clinical Research Center (G.S., E.K., S.M.G., E.G., F.S., M.S.), and Department of Neuropediatrics/SPZ (K.v.A.), Charité-Universitätsmedizin Berlin, Germany; Department of Paediatric Neurology-Neuromuscular Service (H.J.), Evelina Children's Hospital, St Thomas' Hospital, the Randall Division of Cell and Molecular Biophysics, Muscle Signalling Section and the Department of Clinical Neuroscience, IoP, King's College, London, UK; Department of Neuropediatrics, Developmental Neurology and Social Pediatrics (U.S.), University of Essen, Germany; Department of Neurology (F.N.), King's College Hospital, London; Department of Clinical Genetics (C.D.), Guy's Hospital, London, UK; and Friedrich Baur Institute (J.S.), Department of Neurology, Ludwig Maximilians University Munich, Germany.
authors.forename: Esther
authors.initials: E
authors.lastname: Gill
authors.affiliation: From the Department of Neuropediatrics and the NeuroCure Clinical Research Center (G.S., E.K., S.M.G., E.G., F.S., M.S.), and Department of Neuropediatrics/SPZ (K.v.A.), Charité-Universitätsmedizin Berlin, Germany; Department of Paediatric Neurology-Neuromuscular Service (H.J.), Evelina Children's Hospital, St Thomas' Hospital, the Randall Division of Cell and Molecular Biophysics, Muscle Signalling Section and the Department of Clinical Neuroscience, IoP, King's College, London, UK; Department of Neuropediatrics, Developmental Neurology and Social Pediatrics (U.S.), University of Essen, Germany; Department of Neurology (F.N.), King's College Hospital, London; Department of Clinical Genetics (C.D.), Guy's Hospital, London, UK; and Friedrich Baur Institute (J.S.), Department of Neurology, Ludwig Maximilians University Munich, Germany.
authors.forename: Franziska
authors.initials: F
authors.lastname: Seifert
authors.affiliation: From the Department of Neuropediatrics and the NeuroCure Clinical Research Center (G.S., E.K., S.M.G., E.G., F.S., M.S.), and Department of Neuropediatrics/SPZ (K.v.A.), Charité-Universitätsmedizin Berlin, Germany; Department of Paediatric Neurology-Neuromuscular Service (H.J.), Evelina Children's Hospital, St Thomas' Hospital, the Randall Division of Cell and Molecular Biophysics, Muscle Signalling Section and the Department of Clinical Neuroscience, IoP, King's College, London, UK; Department of Neuropediatrics, Developmental Neurology and Social Pediatrics (U.S.), University of Essen, Germany; Department of Neurology (F.N.), King's College Hospital, London; Department of Clinical Genetics (C.D.), Guy's Hospital, London, UK; and Friedrich Baur Institute (J.S.), Department of Neurology, Ludwig Maximilians University Munich, Germany.
authors.forename: Fiona
authors.initials: F
authors.lastname: Norwood
authors.affiliation: From the Department of Neuropediatrics and the NeuroCure Clinical Research Center (G.S., E.K., S.M.G., E.G., F.S., M.S.), and Department of Neuropediatrics/SPZ (K.v.A.), Charité-Universitätsmedizin Berlin, Germany; Department of Paediatric Neurology-Neuromuscular Service (H.J.), Evelina Children's Hospital, St Thomas' Hospital, the Randall Division of Cell and Molecular Biophysics, Muscle Signalling Section and the Department of Clinical Neuroscience, IoP, King's College, London, UK; Department of Neuropediatrics, Developmental Neurology and Social Pediatrics (U.S.), University of Essen, Germany; Department of Neurology (F.N.), King's College Hospital, London; Department of Clinical Genetics (C.D.), Guy's Hospital, London, UK; and Friedrich Baur Institute (J.S.), Department of Neurology, Ludwig Maximilians University Munich, Germany.
authors.forename: Charu
authors.initials: C
authors.lastname: Deshpande
authors.affiliation: From the Department of Neuropediatrics and the NeuroCure Clinical Research Center (G.S., E.K., S.M.G., E.G., F.S., M.S.), and Department of Neuropediatrics/SPZ (K.v.A.), Charité-Universitätsmedizin Berlin, Germany; Department of Paediatric Neurology-Neuromuscular Service (H.J.), Evelina Children's Hospital, St Thomas' Hospital, the Randall Division of Cell and Molecular Biophysics, Muscle Signalling Section and the Department of Clinical Neuroscience, IoP, King's College, London, UK; Department of Neuropediatrics, Developmental Neurology and Social Pediatrics (U.S.), University of Essen, Germany; Department of Neurology (F.N.), King's College Hospital, London; Department of Clinical Genetics (C.D.), Guy's Hospital, London, UK; and Friedrich Baur Institute (J.S.), Department of Neurology, Ludwig Maximilians University Munich, Germany.
authors.forename: Katja
authors.initials: K
authors.lastname: von Au
authors.affiliation: From the Department of Neuropediatrics and the NeuroCure Clinical Research Center (G.S., E.K., S.M.G., E.G., F.S., M.S.), and Department of Neuropediatrics/SPZ (K.v.A.), Charité-Universitätsmedizin Berlin, Germany; Department of Paediatric Neurology-Neuromuscular Service (H.J.), Evelina Children's Hospital, St Thomas' Hospital, the Randall Division of Cell and Molecular Biophysics, Muscle Signalling Section and the Department of Clinical Neuroscience, IoP, King's College, London, UK; Department of Neuropediatrics, Developmental Neurology and Social Pediatrics (U.S.), University of Essen, Germany; Department of Neurology (F.N.), King's College Hospital, London; Department of Clinical Genetics (C.D.), Guy's Hospital, London, UK; and Friedrich Baur Institute (J.S.), Department of Neurology, Ludwig Maximilians University Munich, Germany. markus.schuelke@charite.de.
authors.forename: Markus
authors.initials: M
authors.lastname: Schuelke
authors.affiliation: From the Department of Neuropediatrics and the NeuroCure Clinical Research Center (G.S., E.K., S.M.G., E.G., F.S., M.S.), and Department of Neuropediatrics/SPZ (K.v.A.), Charité-Universitätsmedizin Berlin, Germany; Department of Paediatric Neurology-Neuromuscular Service (H.J.), Evelina Children's Hospital, St Thomas' Hospital, the Randall Division of Cell and Molecular Biophysics, Muscle Signalling Section and the Department of Clinical Neuroscience, IoP, King's College, London, UK; Department of Neuropediatrics, Developmental Neurology and Social Pediatrics (U.S.), University of Essen, Germany; Department of Neurology (F.N.), King's College Hospital, London; Department of Clinical Genetics (C.D.), Guy's Hospital, London, UK; and Friedrich Baur Institute (J.S.), Department of Neurology, Ludwig Maximilians University Munich, Germany.
authors.forename: Jan
authors.initials: J
authors.lastname: Senderek
mesh_terms: D000293:Adolescent; D000328:Adult; D001369:Axons / Q000473:pathology*; D015331:Cohort Studies; D004268:DNA-Binding Proteins / Q000235:genetics*; D005260:Female; D005808:Genes, Recessive / Q000235:genetics; D015417:Hereditary Sensory and Motor Neuropathy / Q000175:diagnosis / Q000235:genetics; D006801:Humans; D008297:Male; D009154:Mutation / Q000235:genetics*; D010375:Pedigree; D010523:Peripheral Nervous System Diseases / Q000175:diagnosis* / Q000235:genetics*; D014157:Transcription Factors / Q000235:genetics*
chemical_list: D004268:DNA-Binding Proteins; C489892:IGHMBP2 protein, human; D014157:Transcription Factors