1
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Safka Brozkova D, Stojkovic T, Haberlová J, Mazanec R, Windhager R, Fernandes Rosenegger P, Hacker S, Züchner S, Kochański A, Leonard‐Louis S, Francou B, Latour P, Senderek J, Seeman P, Auer‐Grumbach M. Demyelinating Charcot–Marie–Tooth neuropathy associated with
FBLN5
mutations. Eur J Neurol 2020; 27:2568-2574. [DOI: 10.1111/ene.14463] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2019] [Accepted: 07/29/2020] [Indexed: 12/14/2022]
Affiliation(s)
- D. Safka Brozkova
- DNA Laboratory Department of Paediatric Neurology 2nd Faculty of Medicine Charles University in Prague and Motol University Hospital Prague Czech Republic
| | - T. Stojkovic
- Centre de Référence des Maladies Neuromusculaires Nord/Est/Ile de France Institut de Myologie APHPG‐H Pitié‐Salpêtrière Paris France
| | - J. Haberlová
- DNA Laboratory Department of Paediatric Neurology 2nd Faculty of Medicine Charles University in Prague and Motol University Hospital Prague Czech Republic
| | - R. Mazanec
- Department of Neurology 2nd Faculty of Medicine Charles University in Prague and Motol University Hospital Prague Czech Republic
| | - R. Windhager
- Department of Orthopaedics and Trauma Surgery Medical University of Vienna Vienna Austria
| | | | - S. Hacker
- Department of Orthopaedics and Trauma Surgery Medical University of Vienna Vienna Austria
| | - S. Züchner
- Dr John T. Macdonald Foundation Department of Human Genetics John P. Hussman Institute for Human Genomics University of Miami Miller School of Medicine Miami FL USA
| | - A. Kochański
- Neuromuscular Unit Mossakowski Medical Research Centre Polish Academy of Sciences Warsaw Poland
| | - S. Leonard‐Louis
- Unité de Pathologie Neuromusculaire Centre de Référence des Maladies Neuromusculaires Nord/Est/Ile de France APHPG‐H Pitié‐Salpêtrière Paris France
| | - B. Francou
- Service de Génétique Moléculaire Pharmacogénétique et Hormonologie APHPHôpital Kremlin‐Bicêtre Paris France
| | - P. Latour
- Service de Biochimie et Biologie Moléculaire Grand Est CHU de LyonGH Est Bron France
| | - J. Senderek
- Department of Neurology Friedrich‐Baur‐Institute LMU Munich Munich Germany
| | - P. Seeman
- DNA Laboratory Department of Paediatric Neurology 2nd Faculty of Medicine Charles University in Prague and Motol University Hospital Prague Czech Republic
| | - M. Auer‐Grumbach
- Department of Orthopaedics and Trauma Surgery Medical University of Vienna Vienna Austria
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2
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Munell F, Gomez-Andrés D, Costa Comellas L, Macaya A, Gratacós M, Dusl M, Senderek J, Lochmüller H. CONGENITAL MYASTHENIC SYNDROMES AND MYASTHENIA. Neuromuscul Disord 2018. [DOI: 10.1016/j.nmd.2018.06.102] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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3
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Laššuthová P, Vill K, Erdem-Ozdamar S, Schröder JM, Topaloglu H, Horvath R, Müller-Felber W, Bansagi B, Schlotter-Weigel B, Gläser D, Neupauerová J, Sedláčková L, Staněk D, Mazanec R, Weis J, Seeman P, Senderek J. Novel SBF2 mutations and clinical spectrum of Charcot-Marie-Tooth neuropathy type 4B2. Clin Genet 2018; 94:467-472. [PMID: 30028002 DOI: 10.1111/cge.13417] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2018] [Revised: 07/04/2018] [Accepted: 07/17/2018] [Indexed: 12/27/2022]
Abstract
Biallelic SBF2 mutations cause Charcot-Marie-Tooth disease type 4B2 (CMT4B2), a sensorimotor neuropathy with autosomal recessive inheritance and association with glaucoma. Since the discovery of the gene mutation, only few additional patients have been reported. We identified seven CMT4B2 families with nine different SBF2 mutations. Revisiting genetic and clinical data from our cohort and the literature, SBF2 variants were private mutations, including exon-deletion and de novo variants. The neuropathy typically started in the first decade after normal early motor development, was predominantly motor and had a rather moderate course. Electrophysiology and nerve biopsies indicated demyelination and excess myelin outfoldings constituted a characteristic feature. While neuropathy was >90% penetrant at age 10 years, glaucoma was absent in ~40% of cases but sometimes developed with age. Consequently, SBF2 mutation analysis should not be restricted to individuals with coincident neuropathy and glaucoma, and CMT4B2 patients without glaucoma should be followed for increased intraocular pressure. The presence of exon-deletion and de novo mutations demands comprehensive mutation scanning and family studies to ensure appropriate diagnostic approaches and genetic counseling.
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Affiliation(s)
- P Laššuthová
- DNA Laboratory, Department of Pediatric Neurology, Charles University and University Hospital Motol, Prague, Czech Republic
| | - K Vill
- Department of Pediatric Neurology, Dr. v. Hauner Children's Hospital, LMU Munich, Munich, Germany
| | - S Erdem-Ozdamar
- Department of Neurology, Faculty of Medicine, Hacettepe University, Ankara, Turkey
| | - J M Schröder
- Institute of Neuropathology, RWTH Aachen University Hospital, Aachen, Germany
| | - H Topaloglu
- Department of Pediatric Neurology, Faculty of Medicine, Hacettepe University, Ankara, Turkey
| | - R Horvath
- Wellcome Centre for Mitochondrial Research, Institute of Genetic Medicine, Newcastle University, Newcastle upon Tyne, UK
| | - W Müller-Felber
- Department of Pediatric Neurology, Dr. v. Hauner Children's Hospital, LMU Munich, Munich, Germany
| | - B Bansagi
- Wellcome Centre for Mitochondrial Research, Institute of Genetic Medicine, Newcastle University, Newcastle upon Tyne, UK
| | - B Schlotter-Weigel
- Friedrich-Baur-Institute, Department of Neurology, University Hospital, LMU Munich, Munich, Germany
| | - D Gläser
- Genetikum, Center for Human Genetics, Neu-Ulm, Germany
| | - J Neupauerová
- DNA Laboratory, Department of Pediatric Neurology, Charles University and University Hospital Motol, Prague, Czech Republic
| | - L Sedláčková
- DNA Laboratory, Department of Pediatric Neurology, Charles University and University Hospital Motol, Prague, Czech Republic
| | - D Staněk
- DNA Laboratory, Department of Pediatric Neurology, Charles University and University Hospital Motol, Prague, Czech Republic
| | - R Mazanec
- Department of Neurology, Charles University and University Hospital Motol, Prague, Czech Republic
| | - J Weis
- Institute of Neuropathology, RWTH Aachen University Hospital, Aachen, Germany
| | - P Seeman
- DNA Laboratory, Department of Pediatric Neurology, Charles University and University Hospital Motol, Prague, Czech Republic
| | - J Senderek
- Friedrich-Baur-Institute, Department of Neurology, University Hospital, LMU Munich, Munich, Germany
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4
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Natera-de Benito D, Töpf A, Vilchez JJ, González-Quereda L, Domínguez-Carral J, Díaz-Manera J, Ortez C, Bestué M, Gallano P, Dusl M, Abicht A, Müller JS, Senderek J, García-Ribes A, Muelas N, Evangelista T, Azuma Y, McMacken G, Paipa Merchan A, Rodríguez Cruz PM, Camacho A, Jiménez E, Miranda-Herrero MC, Santana-Artiles A, García-Campos O, Dominguez-Rubio R, Olivé M, Colomer J, Beeson D, Lochmüller H, Nascimento A. Molecular characterization of congenital myasthenic syndromes in Spain. Neuromuscul Disord 2017; 27:1087-1098. [PMID: 29054425 DOI: 10.1016/j.nmd.2017.08.003] [Citation(s) in RCA: 42] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2017] [Revised: 08/08/2017] [Accepted: 08/10/2017] [Indexed: 10/19/2022]
Abstract
Congenital myasthenic syndromes (CMS) are a heterogeneous group of genetic disorders, all of which impair neuromuscular transmission. Epidemiological data and frequencies of gene mutations are scarce in the literature. Here we describe the molecular genetic and clinical findings of sixty-four genetically confirmed CMS patients from Spain. Thirty-six mutations in the CHRNE, RAPSN, COLQ, GFPT1, DOK7, CHRNG, GMPPB, CHAT, CHRNA1, and CHRNB1 genes were identified in our patients, with five of them not reported so far. These data provide an overview on the relative frequencies of the different CMS subtypes in a large Spanish population. CHRNE mutations are the most common cause of CMS in Spain, accounting for 27% of the total. The second most common are RAPSN mutations. We found a higher rate of GFPT1 mutations in comparison with other populations. Remarkably, several founder mutations made a large contribution to CMS in Spain: RAPSN c.264C > A (p.Asn88Lys), CHRNE c.130insG (Glu44Glyfs*3), CHRNE c.1353insG (p.Asn542Gluf*4), DOK7 c.1124_1127dup (p.Ala378Serfs*30), and particularly frequent in Spain in comparison with other populations, COLQ c.1289A > C (p.Tyr430Ser). Furthermore, we describe phenotypes and distinguishing clinical signs associated with the various CMS genes which might help to identify specific CMS subtypes to guide diagnosis and management.
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Affiliation(s)
- D Natera-de Benito
- Department of Neuromuscular Diseases, Hospital Sant Joan de Déu, CIBERER U703, Barcelona, Spain.
| | - A Töpf
- John Walton Muscular Dystrophy Research Centre, MRC Centre for Neuromuscular Diseases, Institute of Genetic Medicine, Newcastle University, Newcastle upon Tyne NE1 3BZ, UK
| | - J J Vilchez
- Department of Neurology, Hospital Universitari La Fe, Universitat de Valencia, CIBERER U763, Valencia, Spain
| | - L González-Quereda
- Department of Genetics, Hospital de la Santa Creu i Sant Pau and CIBERER U705, Barcelona, Spain
| | - J Domínguez-Carral
- Department of Pediatrics, Hospital Universitario Marqués de Valdecilla, Santander, Spain
| | - J Díaz-Manera
- Neuromuscular Diseases Unit, Department of Neurology, Hospital de la Santa Creu i Sant Pau, Universitat Autònoma de Barcelona and Centre for Biomedical Network Research on Rare Diseases (CIBERER), Barcelona, Spain
| | - C Ortez
- Department of Neuromuscular Diseases, Hospital Sant Joan de Déu, CIBERER U703, Barcelona, Spain
| | - M Bestué
- Department of Neurology, Hospital General San Jorge, Huesca, Spain
| | - P Gallano
- Department of Genetics, Hospital de la Santa Creu i Sant Pau and CIBERER U705, Barcelona, Spain
| | - M Dusl
- Friedrich-Baur-Institute, Ludwig-Maximilians-University Munich, 80336 Munich, Germany
| | - A Abicht
- Friedrich-Baur-Institute, Ludwig-Maximilians-University Munich, 80336 Munich, Germany; Medical Genetics Center, Munich, Germany
| | - J S Müller
- Wellcome Trust Centre for Mitochondrial Research, Institute of Genetic Medicine, Newcastle University, Newcastle upon Tyne, UK
| | - J Senderek
- Friedrich-Baur-Institute, Ludwig-Maximilians-University Munich, 80336 Munich, Germany
| | - A García-Ribes
- Department of Pediatrics, Hospital Universitario Cruces, Bilbao, Spain
| | - N Muelas
- Department of Neurology, Hospital Universitari La Fe, Universitat de Valencia, CIBERER U763, Valencia, Spain
| | - T Evangelista
- John Walton Muscular Dystrophy Research Centre, MRC Centre for Neuromuscular Diseases, Institute of Genetic Medicine, Newcastle University, Newcastle upon Tyne NE1 3BZ, UK
| | - Y Azuma
- John Walton Muscular Dystrophy Research Centre, MRC Centre for Neuromuscular Diseases, Institute of Genetic Medicine, Newcastle University, Newcastle upon Tyne NE1 3BZ, UK
| | - G McMacken
- John Walton Muscular Dystrophy Research Centre, MRC Centre for Neuromuscular Diseases, Institute of Genetic Medicine, Newcastle University, Newcastle upon Tyne NE1 3BZ, UK
| | - A Paipa Merchan
- Neuropathology Unit, Department of Pathology and Neuromuscular Unit, IDIBELL-Hospital Universitari de Bellvitge, Barcelona, Spain
| | - P M Rodríguez Cruz
- Neurosciences Group, Nuffield Department of Clinical Neurosciences, Weatherall Institute of Molecular Medicine, University of Oxford, Oxford OX3 9DS, UK
| | - A Camacho
- Department of Pediatric Neurology, Hospital Universitario 12 de Octubre, Madrid, Spain
| | - E Jiménez
- Department of Pediatrics, Hospital Universitario Rey Juan Carlos, Madrid, Spain
| | - M C Miranda-Herrero
- Department of Neuropediatrics, Hospital General Universitario Gregorio Marañón, Madrid, Spain
| | - A Santana-Artiles
- Department of Neuropediatrics, Complejo Hospitalario Universitario Insular Materno-Infantil, Las Palmas de Gran Canaria, Spain
| | - O García-Campos
- Department of Neuropediatrics, Hospital Virgen de la Salud, Toledo, Spain
| | - R Dominguez-Rubio
- Neuropathology Unit, Department of Pathology and Neuromuscular Unit, IDIBELL-Hospital Universitari de Bellvitge, Barcelona, Spain
| | - M Olivé
- Neuropathology Unit, Department of Pathology and Neuromuscular Unit, IDIBELL-Hospital Universitari de Bellvitge, Barcelona, Spain
| | - J Colomer
- Department of Neuromuscular Diseases, Hospital Sant Joan de Déu, CIBERER U703, Barcelona, Spain
| | - D Beeson
- Neurosciences Group, Nuffield Department of Clinical Neurosciences, Weatherall Institute of Molecular Medicine, University of Oxford, Oxford OX3 9DS, UK
| | - H Lochmüller
- John Walton Muscular Dystrophy Research Centre, MRC Centre for Neuromuscular Diseases, Institute of Genetic Medicine, Newcastle University, Newcastle upon Tyne NE1 3BZ, UK
| | - A Nascimento
- Department of Neuromuscular Diseases, Hospital Sant Joan de Déu, CIBERER U703, Barcelona, Spain
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5
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Braunisch MC, Gallwitz H, Abicht A, Diebold I, Holinski-Feder E, Van Maldergem L, Lammens M, Kovács-Nagy R, Alhaddad B, Strom TM, Meitinger T, Senderek J, Rudnik-Schöneborn S, Haack TB. Extension of the phenotype of biallelic loss-of-function mutations in SLC25A46 to the severe form of pontocerebellar hypoplasia type I. Clin Genet 2017; 93:255-265. [PMID: 28653766 DOI: 10.1111/cge.13084] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2017] [Revised: 06/18/2017] [Accepted: 06/20/2017] [Indexed: 01/04/2023]
Abstract
Biallelic mutations in SLC25A46, encoding a modified solute transporter involved in mitochondrial dynamics, have been identified in a wide range of conditions such as hereditary motor and sensory neuropathy with optic atrophy type VIB (OMIM: *610826) and congenital lethal pontocerebellar hypoplasia (PCH). To date, 18 patients from 13 families have been reported, presenting with the key clinical features of optic atrophy, peripheral neuropathy, and cerebellar atrophy. The course of the disease was highly variable ranging from severe muscular hypotonia at birth and early death to first manifestations in late childhood and survival into the fifties. Here we report on 4 patients from 2 families diagnosed with PCH who died within the first month of life from respiratory insufficiency. Patients from 1 family had pathoanatomically proven spinal motor neuron degeneration (PCH1). Using exome sequencing, we identified biallelic disease-segregating loss-of-function mutations in SLC25A46 in both families. Our study adds to the definition of the SLC25A46-associated phenotypic spectrum that includes neonatal fatalities due to PCH as the severe extreme.
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Affiliation(s)
- M C Braunisch
- Institute of Human Genetics, Klinikum rechts der Isar, Technische Universität München, Munich, Germany.,Department of Nephrology, Klinikum rechts der Isar, Technische Universität München, Munich, Germany
| | - H Gallwitz
- Department of Pediatrics, Socio-Pediatric Center, Klinikum Memmingen, Memmingen, Germany
| | - A Abicht
- Medical Genetics Center, Munich, Germany.,Friedrich-Baur-Institut, Neurologische Klinik und Poliklinik, Klinikum der Universität München, Munich, Germany
| | - I Diebold
- Medical Genetics Center, Munich, Germany
| | - E Holinski-Feder
- Medical Genetics Center, Munich, Germany.,Medizinische Klinik und Poliklinik IV, Campus Innenstadt, Klinikum der Universität München, Munich, Germany
| | - L Van Maldergem
- Center for Human Genetics, University of Franche-Comté, Besançon, France
| | - M Lammens
- Department of Pathology, Antwerp University Hospital, Edegem, Belgium.,Department of Neuropathology, Born Bunge Institute, Antwerp University, Wilrijk, Belgium
| | - R Kovács-Nagy
- Institute of Human Genetics, Klinikum rechts der Isar, Technische Universität München, Munich, Germany
| | - B Alhaddad
- Institute of Human Genetics, Klinikum rechts der Isar, Technische Universität München, Munich, Germany
| | - T M Strom
- Institute of Human Genetics, Klinikum rechts der Isar, Technische Universität München, Munich, Germany.,Institute of Human Genetics, Helmholtz Zentrum München, Neuherberg, Germany
| | - T Meitinger
- Institute of Human Genetics, Klinikum rechts der Isar, Technische Universität München, Munich, Germany.,Institute of Human Genetics, Helmholtz Zentrum München, Neuherberg, Germany
| | - J Senderek
- Friedrich-Baur-Institut, Neurologische Klinik und Poliklinik, Klinikum der Universität München, Munich, Germany
| | - S Rudnik-Schöneborn
- Division of Human Genetics, Medical University Innsbruck, Innsbruck, Austria.,Institut für Humangenetik, Uniklinik RWTH Aachen, Aachen, Germany
| | - T B Haack
- Institute of Human Genetics, Klinikum rechts der Isar, Technische Universität München, Munich, Germany.,Institute of Human Genetics, Helmholtz Zentrum München, Neuherberg, Germany.,Institute of Medical Genetics and Applied Genomics, University of Tübingen, Tübingen, Germany
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6
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Topf A, Azuma Y, Gorokhova S, O'Connor E, Porter A, Harris E, Evangelista T, Cox D, Lorenzoni P, McMacken G, Bartoli M, McArthur D, Magnusson O, Abicht A, Senderek J, Roos A, Abicht A, Lochmüller H. Next generation sequencing technologies in the genetic diagnosis of congenital myasthenic syndrome. Neuromuscul Disord 2017. [DOI: 10.1016/j.nmd.2017.06.373] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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7
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Rudnik-Schöneborn S, Tölle D, Senderek J, Eggermann K, Elbracht M, Kornak U, von der Hagen M, Kirschner J, Leube B, Müller-Felber W, Schara U, von Au K, Wieczorek D, Bußmann C, Zerres K. Diagnostic algorithms in Charcot-Marie-Tooth neuropathies: experiences from a German genetic laboratory on the basis of 1206 index patients. Clin Genet 2015; 89:34-43. [PMID: 25850958 DOI: 10.1111/cge.12594] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2015] [Revised: 03/18/2015] [Accepted: 04/02/2015] [Indexed: 11/30/2022]
Abstract
We present clinical features and genetic results of 1206 index patients and 124 affected relatives who were referred for genetic testing of Charcot-Marie-Tooth (CMT) neuropathy at the laboratory in Aachen between 2001 and 2012. Genetic detection rates were 56% in demyelinating CMT (71% of autosomal dominant (AD) CMT1/CMTX), and 17% in axonal CMT (24% of AD CMT2/CMTX). Three genetic defects (PMP22 duplication/deletion, GJB1/Cx32 or MPZ/P0 mutation) were responsible for 89.3% of demyelinating CMT index patients in whom a genetic diagnosis was achieved, and the diagnostic yield of the three main genetic defects in axonal CMT (GJB1/Cx32, MFN2, MPZ/P0 mutations) was 84.2%. De novo mutations were detected in 1.3% of PMP22 duplication, 25% of MPZ/P0, and none in GJB1/Cx32. Motor nerve conduction velocity was uniformly <38 m/s in median or ulnar nerves in PMP22 duplication, >40 m/s in MFN2, and more variable in GJB1/Cx32, MPZ/P0 mutations. Patients with CMT2A showed a broad clinical severity regardless of the type or position of the MFN2 mutation. Out of 75 patients, 8 patients (11%) with PMP22 deletions were categorized as CMT1 or CMT2. Diagnostic algorithms are still useful for cost-efficient mutation detection and for the interpretation of large-scale genetic data made available by next generation sequencing strategies.
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Affiliation(s)
- S Rudnik-Schöneborn
- Institute of Human Genetics, RWTH Aachen University Hospital, Aachen, Germany
| | - D Tölle
- Institute of Human Genetics, RWTH Aachen University Hospital, Aachen, Germany
| | - J Senderek
- Institute of Human Genetics, RWTH Aachen University Hospital, Aachen, Germany.,Friedrich-Baur-Institute, LMU Munich, Munich, Germany
| | - K Eggermann
- Institute of Human Genetics, RWTH Aachen University Hospital, Aachen, Germany
| | - M Elbracht
- Institute of Human Genetics, RWTH Aachen University Hospital, Aachen, Germany
| | - U Kornak
- Institute of Medical Genetics and Human Genetics, Charité-University Berlin, Berlin, Germany
| | - M von der Hagen
- Abteilung Neuropädiatrie, Medizinische Fakultät Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany
| | - J Kirschner
- Department of Neuropediatrics, University Hospital Freiburg, Freiburg, Germany
| | - B Leube
- Medical Faculty, Institute of Human Genetics and Anthropology, Heinrich-Heine University, Düsseldorf, Germany
| | - W Müller-Felber
- Dr. v. Hauner Childrens Hospital, University of Munich, Munich, Germany
| | - U Schara
- Department of Neuropediatrics, Developmental Neurology and Social Pediatrics, University Essen, Essen, Germany
| | - K von Au
- SPZ Pediatric Neurology, Charité University Berlin, Berlin, Germany
| | - D Wieczorek
- Institute of Human Genetics, University Essen, Essen, Germany
| | - C Bußmann
- Center for Children and Adolescent Medicine, University Clinic Heidelberg, Heidelberg, Germany
| | - K Zerres
- Institute of Human Genetics, RWTH Aachen University Hospital, Aachen, Germany
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8
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Dusl M, Senderek J, Muller JS, Vogel JG, Pertl A, Stucka R, Lochmuller H, David R, Abicht A. A 3'-UTR mutation creates a microRNA target site in the GFPT1 gene of patients with congenital myasthenic syndrome. Hum Mol Genet 2015; 24:3418-26. [DOI: 10.1093/hmg/ddv090] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2015] [Accepted: 03/08/2015] [Indexed: 01/07/2023] Open
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9
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Schottmann G, Jungbluth H, Schara U, Knierim E, Morales Gonzalez S, Gill E, Seifert F, Norwood F, Deshpande C, von Au K, Schuelke M, Senderek J. Recessive truncating IGHMBP2 mutations presenting as axonal sensorimotor neuropathy. Neurology 2015; 84:523-31. [DOI: 10.1212/wnl.0000000000001220] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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10
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Abstract
Charcot-Marie-Tooth disease (CMT) is a heterogeneous group of disorders of the peripheral nervous system, mainly characterized by distal muscle weakness and atrophy leading to motor handicap. With an estimated prevalence of 1 in 2,500, this condition is one of the most commonly inherited neurological disorders. Mutations in more than 30 genes affecting glial and/or neuronal functions have been associated with different forms of CMT leading to a substantial improvement in diagnostics of the disease and in the understanding of implicated pathophysiological mechanisms. However, recent data from systematic genetic screening performed in large cohorts of CMT patients indicated that molecular diagnosis could be established only in ∼50-70% of them, suggesting that additional genes are involved in this disease. In addition to providing an overview of genetic and functional data concerning various CMT forms, this review focuses on recent data generated through the use of highly parallel genetic technologies (SNP chips, sequence capture and next-generation DNA sequencing) in CMT families, and the current and future impact of these technologies on gene discovery and diagnostics of CMTs.
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Affiliation(s)
- H Azzedine
- Department of Medical Genetics, University of Lausanne, Lausanne, Switzerland
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11
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Abstract
Charcot-Marie-Tooth disease (CMT) is a heterogeneous group of disorders of the peripheral nervous system, mainly characterized by distal muscle weakness and atrophy leading to motor handicap. With an estimated prevalence of 1 in 2,500, this condition is one of the most commonly inherited neurological disorders. Mutations in more than 30 genes affecting glial and/or neuronal functions have been associated with different forms of CMT leading to a substantial improvement in diagnostics of the disease and in the understanding of implicated pathophysiological mechanisms. However, recent data from systematic genetic screening performed in large cohorts of CMT patients indicated that molecular diagnosis could be established only in ∼50-70% of them, suggesting that additional genes are involved in this disease. In addition to providing an overview of genetic and functional data concerning various CMT forms, this review focuses on recent data generated through the use of highly parallel genetic technologies (SNP chips, sequence capture and next-generation DNA sequencing) in CMT families, and the current and future impact of these technologies on gene discovery and diagnostics of CMTs.
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Affiliation(s)
- H Azzedine
- Department of Medical Genetics, University of Lausanne, Lausanne, Switzerland
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12
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Kleffmann W, Zink AM, Lee JA, Senderek J, Mangold E, Moog U, Rappold GA, Wohlleber E, Engels H. 5q31 Microdeletions: Definition of a Critical Region and Analysis of LRRTM2, a Candidate Gene for Intellectual Disability. Mol Syndromol 2012; 3:68-75. [PMID: 23326251 DOI: 10.1159/000341252] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/29/2012] [Indexed: 11/19/2022] Open
Abstract
Microdeletions including 5q31 have been reported in only few patients to date. Apart from intellectual disability/developmental delay (ID/DD) of varying degrees, which is common to all reported patients, the clinical spectrum is wide and includes short stature, failure to thrive, congenital heart defects, encephalopathies, and dysmorphic features. We report a patient with a 0.9-Mb de novo deletion in 5q31.2, the smallest microdeletion in 5q31 reported thus far. His clinical presentation includes mild DD, borderline short stature, postnatal microcephaly, and mild dysmorphic signs including microretrognathia. Together with data from 7 reported overlapping microdeletions, analysis of our patient enabled the tentative delineation of a phenotype map for 5q31 deletions. In contrast to the mild phenotype of small microdeletions affecting only 5q31.2, carriers of larger microdeletions which also include subbands 5q31.1 and/or 5q31.3 seem to be more severely affected with congenital malformations, growth anomalies, and severe encephalopathies. A 240-kb smallest region of overlap in 5q31.2 is delineated which contains only 2 genes, CTNNA1 and LRRTM2. We propose LRRTM2 as the most promising candidate gene for ID/DD due to its expression pattern, function as a key regulator of excitatory development, and interaction with Neurexin 1. However, sequence analysis of LRRTM2 in 330 patients with ID/DD revealed no relevant alterations, excluding point mutations in LRRTM2 as a frequent cause of ID/DD in patients without microdeletions.
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Affiliation(s)
- W Kleffmann
- Institute of Human Genetics, Life and Brain Center, University of Bonn, Bonn, Germany
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Colomer J, Nascimento A, Ortez C, Jimenez-Mallabrera C, Jou C, Corbera J, Guergueltcheva V, Senderek J, Müller J, Lochmüller H. P5.20 Limb Girdle Congenital Myasthenia Syndrome associated with mutations in GFPT1 gene. Report of two patients. Neuromuscul Disord 2011. [DOI: 10.1016/j.nmd.2011.06.1049] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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14
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Müller J, Senderek J, Dusl M, Guergueltcheva V, Laval S, Bushby K, Straub V, Beeson D, Abicht A, Lochmüller H. P26 Pyridostigmine-responsive limb-girdle congenital myasthenic syndrome with frequent tubular aggregates. Neuromuscul Disord 2011. [DOI: 10.1016/s0960-8966(11)70045-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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15
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Funke AD, Esser M, Krüttgen A, Weis J, Mitne-Neto M, Lazar M, Nishimura AL, Sperfeld AD, Trillenberg P, Senderek J, Krasnianski M, Zatz M, Zierz S, Deschauer M. The p.P56S mutation in the VAPB gene is not due to a single founder: the first European case. Clin Genet 2010; 77:302-3. [PMID: 20447143 PMCID: PMC2847198 DOI: 10.1111/j.1399-0004.2009.01319.x] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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16
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Senderek J, Garvey SM, Krieger M, Tournev I, Elbracht M, Roos A, Stendel C, Uritzberea A, Guergueltcheva V, Mihailova V, Feit H, Tramonte J, Hedera P, Bergmann C, Rudnik-Schöneborn S, Zerres K, Lochmüller H, Seboun E, Beckmann JS, Hauser MA, Jackson CE, Weis J. Autosomal dominant distal vacuolar myopathy associated with mutation of the nuclear matrix protein matrin 3. Akt Neurol 2009. [DOI: 10.1055/s-0029-1238491] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Moises T, Wüller S, Saxena S, Senderek J, Weis J, Krüttgen A. Proteasomal inhibition alters the trafficking of the neurotrophin receptor TrkA. Biochem Biophys Res Commun 2009; 387:360-4. [PMID: 19607811 DOI: 10.1016/j.bbrc.2009.07.032] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2009] [Accepted: 07/09/2009] [Indexed: 01/07/2023]
Abstract
Neurotrophin receptors of the Trk family promote neuronal survival. The signal transduction of Trk receptors is regulated by endosomal trafficking. Monoubiquitination of receptor tyrosine kinases is an established signal for sorting of internalized receptors to late endosomes. The NGF receptor TrkA is sorted to late endosomes and undergoes ubiquitination, indicating a so far undefined regulatory role of proteasomal activity in the trafficking of TrkA. Surprisingly, we found that proteasomal inhibition alters the trafficking of TrkA from the late endosomal sorting pathway to the recycling pathway. Many neurodegenerative diseases are associated with impaired proteasomal activity. Thus, our study suggests that missorting of neurotrophic receptors might contribute to neuronal death in those neurodegenerative diseases that are known to be associated with impaired proteasomal function.
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Affiliation(s)
- T Moises
- Dept of Neuropathology, Medical Faculty, RWTH Aachen University, 52074 Aachen, Germany
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18
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Seitz CS, van Steensel M, Frank J, Senderek J, Zerres K, Hamm H, Bergmann C. The Wnt signalling ligand RSPO4, causing inherited anonychia, is not mutated in a patient with congenital nail hypoplasia/aplasia with underlying skeletal defects. Br J Dermatol 2007; 157:801-2. [PMID: 17596144 DOI: 10.1111/j.1365-2133.2007.08059.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
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19
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Neusch C, Senderek J, Eggermann T, Elolff E, Bähr M, Schneider-Gold C. Mitofusin 2 gene mutation (R94Q) causing severe early-onset axonal polyneuropathy (CMT2A). Eur J Neurol 2007; 14:575-7. [PMID: 17437620 DOI: 10.1111/j.1468-1331.2006.01688.x] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
Charcot-Marie-Tooth disease (CMT) has been classified into two types: demyelinating forms (CMT1) and axonal forms (CMT2). Mutations in the CMT2A locus have been linked to the KIF1B and the mitofusin 2 (MFN2) genes. Here, we report a German patient with CMT2 with an underlying spontaneous mutation (c.281G-->A) in the MFN2 gene. Clinically, the patient presented with early-onset CMT that was not associated with additional central nervous system pathology. The disease course was rapidly progressive in the first years and slowed afterwards. We also suggest that single patients with early-onset axonal polyneuropathies should be screened for MFN2 mutations.
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Affiliation(s)
- C Neusch
- Department of Neurology, University Göttingen, Göttingen, Germany.
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20
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Bicanski B, Wenderdel M, Mertens PR, Senderek J, Panzer U, Steinmetz O, Stahl RAK, Cerullo G, Diletta Torres D, Schena FP, Zerres K, Floege J. PDGF-B gene single-nucleotide polymorphisms are not predictive for disease onset or progression of IgA nephropathy. Clin Nephrol 2007; 67:65-72. [PMID: 17338425 DOI: 10.5414/cnp67065] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
BACKGROUND Few genetic factors have been identified that determine susceptibility to and progression of IgA-nephropathy (IgAN). Given that IgAN is usually characterized by mesangioproliferative glomerulonephritis and that PDGF-B is of central pathophysiological relevance in this process, we analyzed four single-nucleotide polymorphisms (SNPs) of the PDGF-B gene to evaluate a possible association of these SNPs with disease onset and progression, histological grading and responses to ACE inhibitor (ACEi) therapy. METHODS The total study population consisted of 195 IgAN patients (127 from southern Italy and 68 from northern Germany) and 200 healthy controls (100 from each region). All four SNPs were in Hardy-Weinberg equilibrium and genotype distributions did not differ between patients and controls in either region. RESULTS SNP distribution in Italian patients reaching end-stage renal disease (n=45) also was not significantly different from patients maintaining a serum creatinine below 1.2 mg/dl (n=60) during 5.6 +/- 5.5 years of follow-up. Furthermore, we failed to detect significant effects of any SNP on the slope of 1/serum creatinine, proteinuria level or the antiproteinuric response to ACEi. Additionally, particular PDGF-B genotypes did not correlate with histological grading using the Lee classification. CONCLUSION We conclude that none of the four PDGF-B SNPs is related to the onset of IgAN in two different populations and that none of them has a major influence on the course of IgAN.
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Affiliation(s)
- B Bicanski
- Division of Nephrology and Clinical Immunology, RWTH University of Aachen, Germany.
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21
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Bergmann C, Senderek J, Anhuf D, Thiel CT, Ekici AB, Poblete-Gutierrez P, van Steensel M, Seelow D, Nürnberg G, Schild HH, Nürnberg P, Reis A, Frank J, Zerres K. Mutations in the gene encoding the Wnt-signaling component R-spondin 4 (RSPO4) cause autosomal recessive anonychia. Am J Hum Genet 2006; 79:1105-9. [PMID: 17186469 PMCID: PMC1698700 DOI: 10.1086/509789] [Citation(s) in RCA: 81] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2006] [Accepted: 09/29/2006] [Indexed: 11/03/2022] Open
Abstract
Anonychia is an autosomal recessive disorder characterized by the congenital absence of finger- and toenails. In a large German nonconsanguineous family with four affected and five unaffected siblings with isolated total congenital anonychia, we performed genomewide mapping and showed linkage to 20p13. Analysis of the RSPO4 gene within this interval revealed a frameshift and a nonconservative missense mutation in exon 2 affecting the highly conserved first furin-like cysteine-rich domain. Both mutations were not present among controls and were shown to segregate with the disease phenotype. RSPO4 is a member of the recently described R-spondin family of secreted proteins that play a major role in activating the Wnt/ beta -catenin signaling pathway. Wnt signaling is evolutionarily conserved and plays a pivotal role in embryonic development, growth regulation of multiple tissues, and cancer development. Our findings add to the increasing body of evidence indicating that mesenchymal-epithelial interactions are crucial in nail development and put anonychia on the growing list of congenital malformation syndromes caused by Wnt-signaling-pathway defects. To the best of our knowledge, this is the first gene known to be responsible for an isolated, nonsyndromic nail disorder.
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Affiliation(s)
- C Bergmann
- Department of Human Genetics, Aachen University, Aachen, Germany.
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22
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Senderek J, Krieger M, Stendel C, North K, Muntoni F, Quijano-Roy S, Ebinger F, Schröder J, Voit T, Weis J, Topaloglu H, Zerres K. P.I.5 Mutations in SIL1 cause Marinesco–Sjögren syndrome, a cerebellar ataxia with cataract and myopathy. Neuromuscul Disord 2006. [DOI: 10.1016/j.nmd.2006.05.132] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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23
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Azzedine H, Ravisé N, Verny C, Gabrëels-Festen A, Lammens M, Grid D, Vallat JM, Durosier G, Senderek J, Nouioua S, Hamadouche T, Bouhouche A, Guilbot A, Stendel C, Ruberg M, Brice A, Birouk N, Dubourg O, Tazir M, LeGuern E. Spine deformities in Charcot-Marie-Tooth 4C caused by SH3TC2 gene mutations. Neurology 2006; 67:602-6. [PMID: 16924012 DOI: 10.1212/01.wnl.0000230225.19797.93] [Citation(s) in RCA: 80] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
BACKGROUND Charcot-Marie-Tooth (CMT) disease is a heterogeneous group of inherited peripheral motor and sensory neuropathies with several modes of inheritance: autosomal dominant, X-linked, and autosomal recessive (AR) CMT. A locus responsible for the demyelinating form of ARCMT was assigned to the 5q23-q33 region (CMT4C) by homozygosity mapping. Recently, 11 mutations were identified in the SH3TC2 (KIAA1985) gene in 12 families with demyelinating ARCMT from Turkish, Iranian, Greek, Italian, or German origin. OBJECTIVE To identify mutations in the SH3TC2 gene. METHODS The authors searched for SH3TC2 gene mutations in 10 consanguineous CMT families putatively linked to the CMT4C locus on the basis of haplotype segregation and linkage analysis. RESULTS Ten families had mutations, eight of which were new and one, R954X, recurrent. Six of the 10 mutations were in exon 11. Onset occurred between ages 2 and 10. Scoliosis or kyphoscoliosis and foot deformities were found in almost all patients and were often inaugural. The median motor nerve conduction velocity values (</=34 m/s) were not correlated with disease duration. The functional disability score was </=3, indicating that the patients could walk without help. Unexpectedly, typical giant axons were observed on biopsies from a large Algerian family. CONCLUSIONS Charcot-Marie-Tooth type 4C (CMT4C) is less severe than other autosomal recessive (AR) CMT. Intrafamilial variability is important, making phenotype-genotype correlations difficult, but spine deformities are clearly a hallmark of CMT4C. In the presence of scoliosis, a neurologic examination is recommended. Giant axons on biopsies are also suggestive of CMT4C. For genetic analysis, the R954X mutation should be looked for before systematic sequencing of exon 11.
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Affiliation(s)
- H Azzedine
- INSERM U679 (ex U289), Neurology and Experimental Therapeutics, La Pitié-Salpêtrière Hospital, Paris, France.
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24
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Roos A, Rudnik-Schöneborn S, Eggermann K, Eggermann T, Senderek J, Schwanitz G, Zerres K, Schüler HM. Submicroscopic unbalanced translocation resulting in del10p/dup13q detected by subtelomere FISH. Eur J Med Genet 2006; 49:505-10. [PMID: 16905374 DOI: 10.1016/j.ejmg.2006.06.002] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2006] [Accepted: 06/26/2006] [Indexed: 12/08/2022]
Abstract
Chromosomal rearrangements involving the (sub)telomeres are an important cause of human genetic diseases: with the development of advanced molecular cytogenetic methods they have been identified as a major cause of mental retardation and/or congenital malformation syndromes. We identified a cryptic unbalanced de novo translocation 10p/13q by subtelomere FISH in a boy with mental and growth retardation (karyotype: 46,XY,der(10)t(10;13)(p15.1;q34)(D10S2488-,D13S296+)). Craniofacial dysmorphisms included frontal bossing, epicanthal folds, long philtrum, thin upper lip, short nose, mild retrognathy and a flat midface. In addition the patient had ASDII, a pyloric stenosis, bilateral inguinal hernias and cryptorchidism. His psychomotor development was significantly delayed. Microsatellite typing revealed the paternal origin of the two chromosomes involved in the rearrangement. By comparing our case with previously published patients with similar aberrations we conclude that the congenital malformations in our case are associated with the partial 10p deletion. The craniofacial features might be attributed to the 13q duplication. The identification of a 10p/13q translocation in our case highlights the importance of searching for cryptic subtelomeric imbalances in mentally retarded patients and helps to further delineate genotype-phenotype correlations in rare chromosomal disturbances.
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Affiliation(s)
- A Roos
- Institute of Human Genetics, University Hospital Aachen, Pauwelsstr. 30, D-52074 Aachen, Germany.
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25
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Bergmann C, Küpper F, Schmitt CP, Vester U, Neuhaus TJ, Senderek J, Zerres K. Multi-exon deletions of the PKHD1 gene cause autosomal recessive polycystic kidney disease (ARPKD). J Med Genet 2006; 42:e63. [PMID: 16199545 PMCID: PMC1735935 DOI: 10.1136/jmg.2005.032318] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
BACKGROUND Autosomal recessive polycystic kidney disease (ARPKD) is caused by mutations in the PKHD1 (polycystic kidney and hepatic disease 1) gene on chromosome 6p12, a large gene spanning 470 kb of genomic DNA. So far, only micromutations in the 66 exons encoding the longest open reading frame (ORF) have been described, and account for about 80% of mutations. OBJECTIVE To test the hypothesis that gross genomic rearrangements and mutations in alternatively spliced exons contribute to a subset of the remaining disease alleles. METHODS Using DHPLC for alternatively spliced exons and quantitative real time polymerase chain reaction to detect genomic imbalances, 58 ARPKD patients were screened, of whom 55 were known to harbour one PKHD1 point mutation in the longest ORF. RESULTS Three different heterozygous PKHD1 deletions and several single nucleotide changes in alternatively spliced exons were identified. The detected partial gene deletions are most likely pathogenic, while a potential biological function of the alterations identified in alternatively spliced exons must await the definition of transcripts containing alternative exons and their predicted reading frames. CONCLUSIONS Gross PKHD1 deletions account for a detectable proportion of ARPKD cases. Screening for major genomic PKHD1 rearrangements will further improve mutation analysis in ARPKD.
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Affiliation(s)
- C Bergmann
- Department of Human Genetics, Aachen University, Germany.
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26
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Senderek J, Hermanns B, Lehmann U, Bergmann C, Marx G, Kabus C, Timmerman V, Stoltenburg-Didinger G, Schröder JM. Charcot-Marie-Tooth neuropathy type 2 and P0 point mutations: two novel amino acid substitutions (Asp61Gly; Tyr119Cys) and a possible "hotspot" on Thr124Met. Brain Pathol 2006; 10:235-48. [PMID: 10764043 PMCID: PMC8098375 DOI: 10.1111/j.1750-3639.2000.tb00257.x] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
Mutations in the gene for the major protein component of peripheral nerve myelin, myelin protein zero (MPZ, P0), cause hereditary disorders of Schwann cell myelin such as Charcot-Marie-Tooth neuropathy type 1B (CMT1B), Dejerine-Sottas syndrome (DSS), and congenital hypomyelinating neuropathy (CHN). More recently, P0 mutations were identified in the axonal type of CMT neuropathy, CMT2, which is different from the demyelinating variants with respect to electroneurography and nerve pathology. We screened 49 patients with a clinical and histopathological diagnosis of CMT2 for mutations in the P0 gene. Three heterozygous single nucleotide changes were detected: two novel missense mutations, Asp61Gly and Tyr119Cys, and the known Thr124Met substitution, that has already been reported in several CMT patients from different European countries. Haplotype analysis for the P0 locus proved that our patients with the 124Met allele were not related to a cohort of patients with the same mutation, all of Belgian descent and all found to share a common ancestor. Our data suggest that P0 mutations account for a detectable proportion of CMT2 cases with virtually every patient harbouring a different mutation but recurrence of the Thr124Met amino acid substitution. The high frequency of this peculiar genotype in the European CMT population is presumably not only due to a founder effect but Thr124Met might constitute a mutation hotspot in the P0 gene as well.
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Affiliation(s)
- J Senderek
- Institut für Neuropathologie, Universitätsklinikum der Rheinisch-Westfälischen Technischen Hochschule Aachen, Germany
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Neusch C, Senderek J, Bähr M, Schneider-Gold C. Charcot-Marie-Tooth polyneuropathy type 2A related to a mitofusin 2 gene mutation presenting as severe early-onset axonal polyneuropathy. Akt Neurol 2006. [DOI: 10.1055/s-2006-953303] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Zerres K, Senderek J, Rudnik-Schöneborn S, Eggermann T, Kunze J, Mononen T, Kääriäinen H, Kirfel J, Moser M, Buettner R, Bergmann C. New options for prenatal diagnosis in autosomal recessive polycystic kidney disease by mutation analysis of the PKHD1 gene. Clin Genet 2005; 66:53-7. [PMID: 15200508 DOI: 10.1111/j.0009-9163.2004.00259.x] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Due to the poor prognosis of severe autosomal recessive polycystic kidney disease (ARPKD), there is a strong demand for prenatal diagnosis (PD). Reliable PD testing is possible by molecular genetic analysis only. Although haplotype-based analysis is feasible in most cases, it is associated with a risk of misdiagnosis in families without pathoanatomically proven diagnosis. Linkage analysis is impossible in families where DNA of the index patient is not available. Direct mutation analysis of the recently identified polycystic kidney and hepatic disease 1 gene opens new options in families to whom a reliable PD cannot be offered on the basis of linkage analysis. We for the first time report two cases with PD based on mutation detection, illustrating the new options for PD in ARPKD.
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Affiliation(s)
- K Zerres
- Institute for Human Genetics, Aachen University of Technology, Aachen, Germany.
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Conforti FL, Muglia M, Mazzei R, Patitucci A, Valentino P, Magariello A, Sprovieri T, Bono F, Bergmann C, Gabriele AL, Peluso G, Nisticò R, Senderek J, Quattrone A. A new SBF2 mutation in a family with recessive demyelinating Charcot-Marie-Tooth (CMT4B2). Neurology 2004; 63:1327-8. [PMID: 15477569 DOI: 10.1212/01.wnl.0000140617.02312.80] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Affiliation(s)
- F L Conforti
- Institute of Neurological Sciences, National Research Council, Piano Lago di Mangone, Cosenza, Italy
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Bertini E, Biancalana V, Bolino A, Buj Bello A, Clague M, Guicheney P, Jungbluth H, Kress W, Musaro' A, Nandurkar H, Pirola L, Romero N, Senderek J, Suter U, Sewry C, Tronchere H, Wallgren-Pettersson C, Wishart MJ, Laporte J. 118th ENMC International Workshop on Advances in Myotubular Myopathy. 26-28 September 2003, Naarden, The Netherlands. (5th Workshop of the International Consortium on Myotubular Myopathy). Neuromuscul Disord 2004; 14:387-96. [PMID: 15145343 DOI: 10.1016/j.nmd.2004.04.002] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2004] [Indexed: 11/21/2022]
MESH Headings
- Bacterial Proteins/genetics
- Bacterial Proteins/metabolism
- Charcot-Marie-Tooth Disease/genetics
- Charcot-Marie-Tooth Disease/metabolism
- Chromosomes, Human, X
- Humans
- Insulin-Like Growth Factor I/genetics
- Insulin-Like Growth Factor I/metabolism
- Mutation
- Myopathies, Structural, Congenital/congenital
- Myopathies, Structural, Congenital/diagnosis
- Myopathies, Structural, Congenital/genetics
- Myopathies, Structural, Congenital/therapy
- Netherlands
- Protein Tyrosine Phosphatases/genetics
- Protein Tyrosine Phosphatases/physiology
- Protein Tyrosine Phosphatases, Non-Receptor
- Trans-Activators/genetics
- Trans-Activators/metabolism
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Affiliation(s)
- E Bertini
- Department of Laboratories, Unit of Molecular Medicine, Bambino Gesu' Childrens Hospital, P.za S. Onofrio 4, 00165 Rome, Italy.
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Conforti FL, Muglia M, Mazzei R, Valentino P, Patitucci A, Bono F, Magariello A, Sprovieri T, Senderek J, Bergmann C, Nistico R, Gabriele AL, Peluso G, Quattrone A. A splice-junction mutation in SBF2 gene causes autosomal recessive charcot-marie-tooth disease (CMT4B2) in a family from southern italy. J Peripher Nerv Syst 2004. [DOI: 10.1111/j.1085-9489.2004.009209bn.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Senderek J. Mutation of the SBF2 gene, encoding a novel member of the myotubularin family, in Charcot-Marie-Tooth neuropathy type 4B2/11p15. Hum Mol Genet 2003. [DOI: 10.1093/hmg/ddh030] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Ramaekers VT, Hansen SI, Holm J, Opladen T, Senderek J, Häusler M, Heimann G, Fowler B, Maiwald R, Blau N. Reduced folate transport to the CNS in female Rett patients. Neurology 2003; 61:506-15. [PMID: 12939425 DOI: 10.1212/01.wnl.0000078939.64774.1b] [Citation(s) in RCA: 68] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
BACKGROUND Previous CSF studies in Rett syndrome suggest reduced turnover of the biogenic monoamines serotonin and dopamine. Because diminished turnover may result from CNS folate depletion, the authors studied transport of folate across the blood-brain barrier. METHODS In four patients with Rett syndrome, the authors measured CSF values of 5-methyltetrahydrofolate (5MTHF), biogenic monoamine end-metabolites, and pterins together with serum and red blood cell folate. In CSF, the overall folate binding capacity by the two soluble folate-binding proteins FBP1 and FBP2 (sFBP) was measured using a radioligand binding method for H3-labeled folate. A specific immunoreactive test (ELISA) detected sFBP1, which normally contributes to 30 to 35% of the total folate binding capacity. Genetic analysis included DNA sequencing of the MECP2, FBP1, and FBP2 genes. Empirical treatment with oral folinic acid was evaluated. RESULTS Two patients without and two with mutations of the MECP2 gene had normal values for red blood cell folate, serum folate, homocysteine, and methionine. In CSF, all patients had low values for 5MTHF, neopterin, and the serotonin end-metabolite 5-hydroxyindoleacetic acid (5-HIAA). Genetic analysis of FBP1 and FBP2 genes had normal results. Compared to controls, patients with Rett syndrome had normal immunoreactive sFBP1 in CSF, whereas the total folate binding capacity was disproportionately lowered. Empirical treatment with oral folinic acid normalized 5-MHTF and 5-HIAA levels in CSF, and led to partial clinical improvement. CONCLUSION Irrespective of the MECP2 genotype, 5MTHF transfer to the CNS is reduced in Rett syndrome. Folinic acid supplementation restores 5MTHF levels and serotoninergic turnover. The lowered folate binding capacity of FBP is not explained by a defect of the FBP1 or FBP2 gene, but most likely occurs as a secondary phenomenon in Rett syndrome.
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Affiliation(s)
- V T Ramaekers
- Division of Pediatric Neurology, Department of Pediatrics, University Hospital Aachen, Germany.
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Haubrich C, Krings T, Senderek J, Züchner S, Schröder JM, Noth J, Töpper R. Hypertrophic nerve roots in a case of Roussy-Lévy syndrome. Neuroradiology 2002; 44:933-7. [PMID: 12428130 DOI: 10.1007/s00234-002-0847-2] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2001] [Accepted: 06/28/2002] [Indexed: 11/29/2022]
Abstract
Hypertrophic radiculopathy is a rare feature of neuropathies. Single cases of enlarged nerve roots have been described in hereditary motor sensory neuropathies (HMSN) and chronic inflammatory demyelinating diseases (CIDP). This is the first description of hypertrophied nerve roots in a patient with Roussy-Lévy syndrome. MRI did not show contrast enhancement of the enlarged nerve roots or nodular lesions.
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Affiliation(s)
- C Haubrich
- Neurologische Klinik, Aachen University, Pauwelsstrasse 30, 52074 Aachen, Germany.
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Bergmann C, Zerres K, Rudnik-Schöneborn S, Eggermann T, Schröder JM, Senderek J. Allelic variants in the 5' non-coding region of the connexin32 gene: possible pitfalls in the diagnosis of X linked Charcot-Marie-Tooth neuropathy (CMTX). J Med Genet 2002; 39:e58. [PMID: 12205128 PMCID: PMC1735234 DOI: 10.1136/jmg.39.9.e58] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Affiliation(s)
- C Bergmann
- Institut für Humangenetik, Universitätsklinikum der RWTH Aachen, Germany.
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Senderek J, Ramaekers VT, Zerres K, Rudnik-Schöneborn S, Schröder JM, Bergmann C. Phenotypic variation of a novel nonsense mutation in the P0 intracellular domain. J Neurol Sci 2001; 192:49-51. [PMID: 11701152 DOI: 10.1016/s0022-510x(01)00591-3] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Mutations in the gene for the peripheral myelin protein zero (P0, MPZ) cause type 1B of Charcot-Marie-Tooth sensorimotor neuropathy (CMT1B). Here we report a German family with a novel heterozygous P0 nonsense mutation (G206X) that supposedly removes four-fifths of the amino acid residues constituting the P0 intracellular domain. The 12-year-old propositus had childhood-onset CMT1B associated with bilateral pes cavus, moderate lower limb weakness, and mildly reduced sensory qualities in the distal legs. The electrophysiology was consistent with a demyelinating neuropathy. He inherited the mutation from his mother who had no complaints but slight pes cavus deformity and slow nerve conduction velocities (NCV). Conclusively, truncating mutations within the P0 intracellular domain do not necessarily cause a severe phenotype such as Dejerine-Sottas syndrome (DSS) or congenital hypomyelinating neuropathy (CHN), but can result in mild or moderate CMT1B with intrafamilial clinical variability.
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Affiliation(s)
- J Senderek
- Institut für Neuropathologie, Klinikum der Rheinisch-Westfälischen Technischen Hochschule, Pauwelsstrasse 30, D-52974 Aachen, Germany
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Ramaekers VT, Senderek J, Häusler M, Häring M, Abeling N, Zerres K, Bergmann C, Heimann G, Blau N. A novel neurodevelopmental syndrome responsive to 5-hydroxytryptophan and carbidopa. Mol Genet Metab 2001; 73:179-87. [PMID: 11386854 DOI: 10.1006/mgme.2001.3187] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Tryptophan hydroxylase (TPH; EC 1.14.16.4) catalyzes the first rate-limiting step of serotonin biosynthesis by converting l-tryptophan to 5-hydroxytryptophan. Serotonin controls multiple vegetative functions and modulates sensory and alpha-motor neurons at the spinal level. We report on five boys with floppiness in infancy followed by motor delay, development of a hypotonic-ataxic syndrome, learning disability, and short attention span. Cerebrospinal fluid (CSF) analysis showed a 51 to 65% reduction of the serotonin end-metabolite 5-hydroxyindoleacetic acid (5HIAA) compared to age-matched median values. In one out of five patients a low CSF 5-methyltetrahydrofolate (MTHF) was present probably due to the common C677T heterozygous mutation of the methylenetetrahydrofolate reductase (MTHFR) gene. Baseline 24-h urinary excretion showed diminished 5HIAA values, not changing after a single oral load with l-tryptophan (50-70 mg/kg), but normalizing after 5-hydroxytryptophan administration (1 mg/kg). Treatment with 5-hydroxytryptophan (4-6 mg/kg) and carbidopa (0.5-1.0 mg/kg) resulted in clinical amelioration and normalization of 5HIAA levels in CSF and urine. In the patient with additional MTHFR heterozygosity, a heterozygous missense mutation within exon 6 (G529A) of the TPH gene caused an exchange of valine by isoleucine at codon 177 (V177I). This has been interpreted as a rare DNA variant because the pedigree analysis did not provide any genotype-phenotype correlation. In the other four patients the TPH gene analysis was normal. In conclusion, this new neurodevelopmental syndrome responsive to treatment with 5-hydroxytryptophan and carbidopa might result from an overall reduced capacity of serotonin production due to a TPH gene regulatory defect, unknown factors inactivating the TPH enzyme, or selective loss of serotonergic neurons.
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Affiliation(s)
- V T Ramaekers
- Division of Paediatric Neurology, Department of Pediatrics, University Hospital Aachen, 52074 Aachen, Germany.
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Bergmann C, Schröder JM, Rudnik-Schöneborn S, Zerres K, Senderek J. A point mutation in the human connexin32 promoter P2 does not correlate with X-linked dominant Charcot-Marie-Tooth neuropathy in Germany. Brain Res Mol Brain Res 2001; 88:183-5. [PMID: 11295246 DOI: 10.1016/s0169-328x(01)00040-7] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
The sensorimotor neuropathy Charcot-Marie-Tooth disease (CMT) is the most common hereditary disorder of the peripheral nervous system. The X-linked dominant form of CMT (CMTX) is associated with mutations in the connexin32 gene (Cx32). The majority of CMTX cases harbour mutations in the coding region while a few cases have been reported to result from mutations in the promoter region. We found a G-713A transition of the nerve specific Cx32 promoter P2 in the Caucasian German population. The allele frequency reached 50%, both in CMT patients and in healthy control individuals. In contrast, in an earlier contribution to this journal [Brain Res. Mol. Brain Res.78 (2000) 146], the same base transition was reported to cause CMTX in a Taiwanese family. These divergent results are important for genetic counselling and require careful consideration of ethnic backgrounds and of diagnostic and experimental pitfalls.
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Affiliation(s)
- C Bergmann
- Institut für Humangenetik, Universitätsklinikum der RWTH Aachen, Pauwelsstrasse 30, D-52074 Aachen, Germany.
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Senderek J, Hermanns B, Lehmann U, Bergmann C, Marx G, Kabus C, Timmerman V, Stoltenburg‐Didinger G, Schroder J. Charcot‐Marie‐Tooth Neuropathy Type 2 And P0 Point Mutations: Two Novel Amino Acid Substitutions (ASP61GLY, TYR119CYS) and a Possible “Hotspot” on THR124MET. J Peripher Nerv Syst 2000. [DOI: 10.1046/j.1529-8027.2000.absjun-14.x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Affiliation(s)
- J. Senderek
- Brain Pathology 10: 235–248, 2000. Reprinted with permission from International Society of Neuropathology
| | - B. Hermanns
- Brain Pathology 10: 235–248, 2000. Reprinted with permission from International Society of Neuropathology
| | - U. Lehmann
- Brain Pathology 10: 235–248, 2000. Reprinted with permission from International Society of Neuropathology
| | - C. Bergmann
- Brain Pathology 10: 235–248, 2000. Reprinted with permission from International Society of Neuropathology
| | - G. Marx
- Brain Pathology 10: 235–248, 2000. Reprinted with permission from International Society of Neuropathology
| | - C. Kabus
- Brain Pathology 10: 235–248, 2000. Reprinted with permission from International Society of Neuropathology
| | - V. Timmerman
- Brain Pathology 10: 235–248, 2000. Reprinted with permission from International Society of Neuropathology
| | - G. Stoltenburg‐Didinger
- Brain Pathology 10: 235–248, 2000. Reprinted with permission from International Society of Neuropathology
| | - J.M. Schroder
- Brain Pathology 10: 235–248, 2000. Reprinted with permission from International Society of Neuropathology
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Abstract
A man was identified with two X-chromosomal neuromuscular disorders, X-linked Charcot-Marie-Tooth disease (CMTX) and Becker muscular dystrophy (BMD). The neuropathy could be tracked in the family and was found to be caused by a mutation in the connexin32 gene on Xq13. 1. The muscular dystrophy was sporadic owing to a de novo deletion in the dystrophin gene located in band Xp21.2. Although these genetic alterations of the same X-chromosome are considered as physically independent, their combination resulted in a unique phenotype with severe wasting of proximal as well as distal muscles and rapid progression of both conditions.
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Affiliation(s)
- C Bergmann
- Institut für Neuropathologie der Rheinisch-Westfälischen Technischen Hochschule, Pauwelsstrasse 30, D-52074 Aachen, Germany
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Senderek J, Hermanns B, Bergmann C, Boroojerdi B, Bajbouj M, Hungs M, Ramaekers VT, Quasthoff S, Karch D, Schröder JM. X-linked dominant Charcot-Marie-Tooth neuropathy: clinical, electrophysiological, and morphological phenotype in four families with different connexin32 mutations(1). J Neurol Sci 1999; 167:90-101. [PMID: 10521546 DOI: 10.1016/s0022-510x(99)00146-x] [Citation(s) in RCA: 56] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
The sensorimotor neuropathy of the Charcot-Marie-Tooth type (CMT) is the most common hereditary disorder of the peripheral nervous system. The X-linked dominant form of CMT (CMTX) is associated with mutations in the gene for the gap junction protein connexin32. We examined four CMTX pedigrees two of which had potentially novel mutations in the only coding exon of connexin32. One previously unreported missense mutation, Ala39Val, was found in a family displaying a CMT phenotype with additional upper limb postural tremor reminiscent of a Roussy-Lévy syndrome. A novel single base insertion, 679insT, is among the first mutations found in the fourth transmembrane domain of connexin32. Frameshift and premature stop of translation are supposed to result in a non-functional carboxy-terminus. Two further families had the known missense mutations Arg15Trp and Arg22Gln. Several female carriers were found normal on clinical presentation, however, the genotype was paralleled by decreased nerve conduction velocities (NCV) and slowed central conduction of brain stem auditory evoked responses (BAER). Median motor NCVs showed mild (in women) to intermediate (in males) reduction, indicating a peripheral neuropathy with a predominating axonal component. Nerve biopsy findings were consistent with the electrophysiological data showing a marked loss of large myelinated fibres and clusters of regenerating axons. Electron microscopy revealed various alterations of the axoglial attachment zone. This suggests defective axon-Schwann cell interactions which may induce the axonopathy in CMTX.
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Affiliation(s)
- J Senderek
- Institut für Neuropathologie, Universitätsklinikum der Rheinisch-Westfälischen Technischen Hochschule, Pauwelsstrasse 30, D-52074, Aachen, Germany
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Senderek J, Bergmann C, Quasthoff S, Ramaekers VT, Schröder JM. X-linked dominant Charcot-Marie-Tooth disease: nerve biopsies allow morphological evaluation and detection of connexin32 mutations (Arg15Trp, Arg22Gln). Acta Neuropathol 1998; 95:443-9. [PMID: 9600589 DOI: 10.1007/s004010050823] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
X-linked Charcot-Marie-Tooth neuropathy (CMTX) is caused by mutations in the connexin32 gene on Xq13. Because of overlapping morphological and clinical data, CMTX patients often meet the criteria of autosomal-dominant CMT2, the neuronal type of CMT. Hence, it might be useful to analyse the connexin32 gene in suspected CMT2 patients when there is no male-to-male transmission. We selected a cohort of 30 patients who were considered having CMT2 on the basis of previous clinical and histopathological evaluation. DNA was extracted from paraffin-embedded sural nerve biopsy samples and screened for connexin32 mutations to verify the possible diagnosis of CMTX. In 2 patients mutations were found corresponding to amino acid substitutions of arginine for tryptophan in codon 15 and arginine for glutamine in codon 22 of connexin32. This study illustrates that archival material allows genetic classification of suspected CMT cases. Furthermore, there is additional proof that connexin32 mutations represent the underlying genetic defect in some cases of predominantly neuronal CMT.
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Affiliation(s)
- J Senderek
- Institut für Neuropathologie, Universitätsklinikum der RWTH Aachen, Germany
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