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Erbe LS, Hoffjan S, Janßen S, Kneifel M, Krause K, Gerding WM, Döring K, Güttsches AK, Roos A, Buena Atienza E, Gross C, Lücke T, Nguyen HHP, Vorgerd M, Köhler C. Exome Sequencing and Optical Genome Mapping in Molecularly Unsolved Cases of Duchenne Muscular Dystrophy: Identification of a Causative X-Chromosomal Inversion Disrupting the DMD Gene. Int J Mol Sci 2023; 24:14716. [PMID: 37834164 PMCID: PMC10572545 DOI: 10.3390/ijms241914716] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2023] [Revised: 09/25/2023] [Accepted: 09/26/2023] [Indexed: 10/15/2023] Open
Abstract
Duchenne muscular dystrophy (DMD) is a severe progressive muscle disease that mainly affects boys due to X-linked recessive inheritance. In most affected individuals, MLPA or sequencing-based techniques detect deletions, duplications, or point mutations in the dystrophin-encoding DMD gene. However, in a small subset of patients clinically diagnosed with DMD, the molecular cause is not identified with these routine methods. Evaluation of the 60 DMD patients in our center revealed three cases without a known genetic cause. DNA samples of these patients were analyzed using whole-exome sequencing (WES) and, if unconclusive, optical genome mapping (OGM). WES led to a diagnosis in two cases: one patient was found to carry a splice mutation in the DMD gene that had not been identified during previous Sanger sequencing. In the second patient, we detected two variants in the fukutin gene (FKTN) that were presumed to be disease-causing. In the third patient, WES was unremarkable, but OGM identified an inversion disrupting the DMD gene (~1.28 Mb) that was subsequently confirmed with long-read sequencing. These results highlight the importance of reanalyzing unsolved cases using WES and demonstrate that OGM is a useful method for identifying large structural variants in cases with unremarkable exome sequencing.
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Affiliation(s)
- Leoni S. Erbe
- Department of Human Genetics, Ruhr-University Bochum, 44801 Bochum, Germany; (L.S.E.); (W.M.G.); (K.D.); (H.H.P.N.)
| | - Sabine Hoffjan
- Department of Human Genetics, Ruhr-University Bochum, 44801 Bochum, Germany; (L.S.E.); (W.M.G.); (K.D.); (H.H.P.N.)
- Center for Rare Diseases Ruhr (CeSER), 44791 Bochum, Germany; (C.K.); (T.L.)
| | - Sören Janßen
- Department of Neuropediatrics, University Children’s Hospital, Ruhr-University Bochum, 44801 Bochum, Germany;
| | - Moritz Kneifel
- Department of Neurology, Heimer Institute for Muscle Research, University Hospital Bergmannsheil, Ruhr-University Bochum, 44801 Bochum, Germany; (M.K.); (K.K.); (A.-K.G.); (A.R.); (M.V.)
| | - Karsten Krause
- Department of Neurology, Heimer Institute for Muscle Research, University Hospital Bergmannsheil, Ruhr-University Bochum, 44801 Bochum, Germany; (M.K.); (K.K.); (A.-K.G.); (A.R.); (M.V.)
| | - Wanda M. Gerding
- Department of Human Genetics, Ruhr-University Bochum, 44801 Bochum, Germany; (L.S.E.); (W.M.G.); (K.D.); (H.H.P.N.)
| | - Kristina Döring
- Department of Human Genetics, Ruhr-University Bochum, 44801 Bochum, Germany; (L.S.E.); (W.M.G.); (K.D.); (H.H.P.N.)
| | - Anne-Katrin Güttsches
- Department of Neurology, Heimer Institute for Muscle Research, University Hospital Bergmannsheil, Ruhr-University Bochum, 44801 Bochum, Germany; (M.K.); (K.K.); (A.-K.G.); (A.R.); (M.V.)
| | - Andreas Roos
- Department of Neurology, Heimer Institute for Muscle Research, University Hospital Bergmannsheil, Ruhr-University Bochum, 44801 Bochum, Germany; (M.K.); (K.K.); (A.-K.G.); (A.R.); (M.V.)
| | - Elena Buena Atienza
- Institute of Medical Genetics and Applied Genomics, University Tübingen, 72074 Tübingen, Germany; (E.B.A.); (C.G.)
- NGS Competence Center Tübingen, 72076 Tübingen, Germany
| | - Caspar Gross
- Institute of Medical Genetics and Applied Genomics, University Tübingen, 72074 Tübingen, Germany; (E.B.A.); (C.G.)
- NGS Competence Center Tübingen, 72076 Tübingen, Germany
| | - Thomas Lücke
- Center for Rare Diseases Ruhr (CeSER), 44791 Bochum, Germany; (C.K.); (T.L.)
- Department of Neuropediatrics, University Children’s Hospital, Ruhr-University Bochum, 44801 Bochum, Germany;
| | - Hoa Huu Phuc Nguyen
- Department of Human Genetics, Ruhr-University Bochum, 44801 Bochum, Germany; (L.S.E.); (W.M.G.); (K.D.); (H.H.P.N.)
- Center for Rare Diseases Ruhr (CeSER), 44791 Bochum, Germany; (C.K.); (T.L.)
| | - Matthias Vorgerd
- Department of Neurology, Heimer Institute for Muscle Research, University Hospital Bergmannsheil, Ruhr-University Bochum, 44801 Bochum, Germany; (M.K.); (K.K.); (A.-K.G.); (A.R.); (M.V.)
| | - Cornelia Köhler
- Center for Rare Diseases Ruhr (CeSER), 44791 Bochum, Germany; (C.K.); (T.L.)
- Department of Neuropediatrics, University Children’s Hospital, Ruhr-University Bochum, 44801 Bochum, Germany;
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2
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Bouchard C, Tremblay JP. Limb-Girdle Muscular Dystrophies Classification and Therapies. J Clin Med 2023; 12:4769. [PMID: 37510884 PMCID: PMC10381329 DOI: 10.3390/jcm12144769] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2023] [Revised: 07/05/2023] [Accepted: 07/18/2023] [Indexed: 07/30/2023] Open
Abstract
Limb-girdle muscular dystrophies (LGMDs) are caused by mutations in multiple genes. This review article presents 39 genes associated with LGMDs. Some forms are inherited in a dominant fashion, while for others this occurs recessively. The classification of LGMDs has evolved through time. Lately, to be considered an LGMD, the mutation has to cause a predominant proximal muscle weakness and must be found in two or more unrelated families. This article also presents therapies for LGMDs, examining both available treatments and those in development. For now, only symptomatic treatments are available for patients. The goal is now to solve the problem at the root of LGMDs instead of treating each symptom individually. In the last decade, multiple other potential treatments were developed and studied, such as stem-cell transplantation, exon skipping, gene delivery, RNAi, and gene editing.
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Affiliation(s)
- Camille Bouchard
- Departement de Médecine Moléculaire, Université Laval, Quebec, QC G1V 0A6, Canada
- Centre de Recherche du Centre Hospitalier Universitaire de Quebec, Quebec, QC G1E 6W2, Canada
| | - Jacques P Tremblay
- Departement de Médecine Moléculaire, Université Laval, Quebec, QC G1V 0A6, Canada
- Centre de Recherche du Centre Hospitalier Universitaire de Quebec, Quebec, QC G1E 6W2, Canada
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3
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Okuma H, Hord JM, Chandel I, Venzke D, Anderson ME, Walimbe AS, Joseph S, Gastel Z, Hara Y, Saito F, Matsumura K, Campbell KP. N-terminal domain on dystroglycan enables LARGE1 to extend matriglycan on α-dystroglycan and prevents muscular dystrophy. eLife 2023; 12:e82811. [PMID: 36723429 PMCID: PMC9917425 DOI: 10.7554/elife.82811] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2022] [Accepted: 01/31/2023] [Indexed: 02/02/2023] Open
Abstract
Dystroglycan (DG) requires extensive post-translational processing and O-glycosylation to function as a receptor for extracellular matrix (ECM) proteins containing laminin-G (LG) domains. Matriglycan is an elongated polysaccharide of alternating xylose (Xyl) and glucuronic acid (GlcA) that binds with high affinity to ECM proteins with LG domains and is uniquely synthesized on α-dystroglycan (α-DG) by like-acetylglucosaminyltransferase-1 (LARGE1). Defects in the post-translational processing or O-glycosylation of α-DG that result in a shorter form of matriglycan reduce the size of α-DG and decrease laminin binding, leading to various forms of muscular dystrophy. Previously, we demonstrated that protein O-mannose kinase (POMK) is required for LARGE1 to generate full-length matriglycan on α-DG (~150-250 kDa) (Walimbe et al., 2020). Here, we show that LARGE1 can only synthesize a short, non-elongated form of matriglycan in mouse skeletal muscle that lacks the DG N-terminus (α-DGN), resulting in an ~100-125 kDa α-DG. This smaller form of α-DG binds laminin and maintains specific force but does not prevent muscle pathophysiology, including reduced force production after eccentric contractions (ECs) or abnormalities in the neuromuscular junctions. Collectively, our study demonstrates that α-DGN, like POMK, is required for LARGE1 to extend matriglycan to its full mature length on α-DG and thus prevent muscle pathophysiology.
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Affiliation(s)
- Hidehiko Okuma
- Howard Hughes Medical Institute, Senator Paul D. Wellstone Muscular Dystrophy Specialized Research Center, Department of Molecular Physiology and Biophysics and Department of Neurology, Roy J. and Lucille A. Carver College of Medicine, The University of IowaIowa CityUnited States
| | - Jeffrey M Hord
- Howard Hughes Medical Institute, Senator Paul D. Wellstone Muscular Dystrophy Specialized Research Center, Department of Molecular Physiology and Biophysics and Department of Neurology, Roy J. and Lucille A. Carver College of Medicine, The University of IowaIowa CityUnited States
| | - Ishita Chandel
- Howard Hughes Medical Institute, Senator Paul D. Wellstone Muscular Dystrophy Specialized Research Center, Department of Molecular Physiology and Biophysics and Department of Neurology, Roy J. and Lucille A. Carver College of Medicine, The University of IowaIowa CityUnited States
| | - David Venzke
- Howard Hughes Medical Institute, Senator Paul D. Wellstone Muscular Dystrophy Specialized Research Center, Department of Molecular Physiology and Biophysics and Department of Neurology, Roy J. and Lucille A. Carver College of Medicine, The University of IowaIowa CityUnited States
| | - Mary E Anderson
- Howard Hughes Medical Institute, Senator Paul D. Wellstone Muscular Dystrophy Specialized Research Center, Department of Molecular Physiology and Biophysics and Department of Neurology, Roy J. and Lucille A. Carver College of Medicine, The University of IowaIowa CityUnited States
| | - Ameya S Walimbe
- Howard Hughes Medical Institute, Senator Paul D. Wellstone Muscular Dystrophy Specialized Research Center, Department of Molecular Physiology and Biophysics and Department of Neurology, Roy J. and Lucille A. Carver College of Medicine, The University of IowaIowa CityUnited States
| | - Soumya Joseph
- Howard Hughes Medical Institute, Senator Paul D. Wellstone Muscular Dystrophy Specialized Research Center, Department of Molecular Physiology and Biophysics and Department of Neurology, Roy J. and Lucille A. Carver College of Medicine, The University of IowaIowa CityUnited States
| | - Zeita Gastel
- Howard Hughes Medical Institute, Senator Paul D. Wellstone Muscular Dystrophy Specialized Research Center, Department of Molecular Physiology and Biophysics and Department of Neurology, Roy J. and Lucille A. Carver College of Medicine, The University of IowaIowa CityUnited States
| | - Yuji Hara
- Department Pharmaceutical Sciences, School of Pharmaceutical Sciences, University of ShizuokaShizuokaJapan
| | - Fumiaki Saito
- Department of Neurology, School of Medicine, Teikyo UniversityTokyoJapan
| | - Kiichiro Matsumura
- Department of Neurology, School of Medicine, Teikyo UniversityTokyoJapan
| | - Kevin P Campbell
- Howard Hughes Medical Institute, Senator Paul D. Wellstone Muscular Dystrophy Specialized Research Center, Department of Molecular Physiology and Biophysics and Department of Neurology, Roy J. and Lucille A. Carver College of Medicine, The University of IowaIowa CityUnited States
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Gaertner A, Burr L, Klauke B, Brodehl A, Laser KT, Klingel K, Tiesmeier J, Schulz U, zu Knyphausen E, Gummert J, Milting H. Compound Heterozygous FKTN Variants in a Patient with Dilated Cardiomyopathy Led to an Aberrant α-Dystroglycan Pattern. Int J Mol Sci 2022; 23:ijms23126685. [PMID: 35743126 PMCID: PMC9223741 DOI: 10.3390/ijms23126685] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2022] [Revised: 06/13/2022] [Accepted: 06/14/2022] [Indexed: 02/01/2023] Open
Abstract
Fukutin encoded by FKTN is a ribitol 5-phosphate transferase involved in glycosylation of α-dystroglycan. It is known that mutations in FKTN affect the glycosylation of α-dystroglycan, leading to a dystroglycanopathy. Dystroglycanopathies are a group of syndromes with a broad clinical spectrum including dilated cardiomyopathy and muscular dystrophy. In this study, we reported the case of a patient with muscular dystrophy, early onset dilated cardiomyopathy, and elevated creatine kinase levels who was a carrier of the compound heterozygous variants p.Ser299Arg and p.Asn442Ser in FKTN. Our work showed that compound heterozygous mutations in FKTN lead to a loss of fully glycosylated α-dystroglycan and result in cardiomyopathy and end-stage heart failure at a young age.
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Affiliation(s)
- Anna Gaertner
- Erich und Hanna Klessmann-Institut für Kardiovaskuläre Forschung und Entwicklung, Klinik für Thorax- und Kardiovaskularchirurgie, Herz und Diabeteszentrum NRW, Universitätsklinikum der Ruhr-Universität Bochum, Georgstr. 11, 32545 Bad Oeynhausen, Germany; (L.B.); (B.K.); (A.B.); (J.T.); (U.S.); (J.G.)
- Correspondence: (A.G.); (H.M.)
| | - Lidia Burr
- Erich und Hanna Klessmann-Institut für Kardiovaskuläre Forschung und Entwicklung, Klinik für Thorax- und Kardiovaskularchirurgie, Herz und Diabeteszentrum NRW, Universitätsklinikum der Ruhr-Universität Bochum, Georgstr. 11, 32545 Bad Oeynhausen, Germany; (L.B.); (B.K.); (A.B.); (J.T.); (U.S.); (J.G.)
| | - Baerbel Klauke
- Erich und Hanna Klessmann-Institut für Kardiovaskuläre Forschung und Entwicklung, Klinik für Thorax- und Kardiovaskularchirurgie, Herz und Diabeteszentrum NRW, Universitätsklinikum der Ruhr-Universität Bochum, Georgstr. 11, 32545 Bad Oeynhausen, Germany; (L.B.); (B.K.); (A.B.); (J.T.); (U.S.); (J.G.)
| | - Andreas Brodehl
- Erich und Hanna Klessmann-Institut für Kardiovaskuläre Forschung und Entwicklung, Klinik für Thorax- und Kardiovaskularchirurgie, Herz und Diabeteszentrum NRW, Universitätsklinikum der Ruhr-Universität Bochum, Georgstr. 11, 32545 Bad Oeynhausen, Germany; (L.B.); (B.K.); (A.B.); (J.T.); (U.S.); (J.G.)
| | - Kai Thorsten Laser
- Zentrum für Angeborene Herzfehler, Herz und Diabeteszentrum NRW, Universitätsklinikum der Ruhr-Universität Bochum, Georgstr. 11, 32545 Bad Oeynhausen, Germany; (K.T.L.); (E.z.K.)
| | - Karin Klingel
- Kardiopathologie, Institut für Pathologie und Neuropathologie, Universitätsklinikum Tübingen, Liebermeisterstraße 8, 72076 Tübingen, Germany;
| | - Jens Tiesmeier
- Erich und Hanna Klessmann-Institut für Kardiovaskuläre Forschung und Entwicklung, Klinik für Thorax- und Kardiovaskularchirurgie, Herz und Diabeteszentrum NRW, Universitätsklinikum der Ruhr-Universität Bochum, Georgstr. 11, 32545 Bad Oeynhausen, Germany; (L.B.); (B.K.); (A.B.); (J.T.); (U.S.); (J.G.)
| | - Uwe Schulz
- Erich und Hanna Klessmann-Institut für Kardiovaskuläre Forschung und Entwicklung, Klinik für Thorax- und Kardiovaskularchirurgie, Herz und Diabeteszentrum NRW, Universitätsklinikum der Ruhr-Universität Bochum, Georgstr. 11, 32545 Bad Oeynhausen, Germany; (L.B.); (B.K.); (A.B.); (J.T.); (U.S.); (J.G.)
| | - Edzard zu Knyphausen
- Zentrum für Angeborene Herzfehler, Herz und Diabeteszentrum NRW, Universitätsklinikum der Ruhr-Universität Bochum, Georgstr. 11, 32545 Bad Oeynhausen, Germany; (K.T.L.); (E.z.K.)
| | - Jan Gummert
- Erich und Hanna Klessmann-Institut für Kardiovaskuläre Forschung und Entwicklung, Klinik für Thorax- und Kardiovaskularchirurgie, Herz und Diabeteszentrum NRW, Universitätsklinikum der Ruhr-Universität Bochum, Georgstr. 11, 32545 Bad Oeynhausen, Germany; (L.B.); (B.K.); (A.B.); (J.T.); (U.S.); (J.G.)
| | - Hendrik Milting
- Erich und Hanna Klessmann-Institut für Kardiovaskuläre Forschung und Entwicklung, Klinik für Thorax- und Kardiovaskularchirurgie, Herz und Diabeteszentrum NRW, Universitätsklinikum der Ruhr-Universität Bochum, Georgstr. 11, 32545 Bad Oeynhausen, Germany; (L.B.); (B.K.); (A.B.); (J.T.); (U.S.); (J.G.)
- Correspondence: (A.G.); (H.M.)
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5
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Taghizadeh E, Rezaee M, Barreto GE, Sahebkar A. Prevalence, pathological mechanisms, and genetic basis of limb-girdle muscular dystrophies: A review. J Cell Physiol 2018; 234:7874-7884. [PMID: 30536378 DOI: 10.1002/jcp.27907] [Citation(s) in RCA: 45] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2018] [Accepted: 10/23/2018] [Indexed: 12/17/2022]
Abstract
Limb-girdle muscular dystrophies (LGMDs) are a highly heterogeneous group of neuromuscular disorders that are associated with weakness and wasting of muscles in legs and arms. Signs and symptoms may begin at any age and usually worsen by time. LGMDs are autosomal disorders with different types and their prevalence is not the same in different areas. New technologies such as next-generation sequencing can accelerate their diagnosis. Several important pathological mechanisms that are involved in the pathology of the LGMD include abnormalities in dystrophin-glycoprotein complex, the sarcomere, glycosylation of dystroglycan, vesicle and molecular trafficking, signal transduction pathways, and nuclear functions. Here, we provide a comprehensive review that integrates LGMD clinical manifestations, prevalence, and some pathological mechanisms involved in LGMDs.
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Affiliation(s)
- Eskandar Taghizadeh
- Cellular and Molecular Research Center, Yasuj University of Medical Sciences, Yasuj, Iran.,Department of Medical Genetics, Faculity of Medicine, Mashhad University of Medical Science, Mashhad, Iran
| | - Mehdi Rezaee
- Department of Medical Biotechnology, School of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran
| | - George E Barreto
- Departamento de Nutrición y Bioquímica, Facultad de Ciencias, Pontificia Universidad Javeriana, Bogotá D.C, Colombia.,Instituto de Ciencias Biomédicas, Universidad Autónoma de Chile, Santiago, Chile
| | - Amirhossein Sahebkar
- Biotechnology Research Center, Pharmaceutical Technology Institute, Mashhad University of Medical Science, Mashhad, Iran.,Neurogenic Inflammation Research Center, Mashhad University of Medical Science, Mashhad, Iran.,School of Pharmacy, Mashhad University of Medical Science, Mashhad, Iran
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6
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Angelini C, Fanin M. Limb girdle muscular dystrophies: clinical-genetical diagnostic update and prospects for therapy. Expert Opin Orphan Drugs 2017. [DOI: 10.1080/21678707.2017.1367283] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Affiliation(s)
- Corrado Angelini
- Department of Neurodegenerative Disorders, Neuromuscular Center, San Camillo Hospital IRCCS, Venice, Italy
| | - Marina Fanin
- Department of Neurosciences, University of Padova, Padova, Italy
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Smogavec M, Zschüntzsch J, Kress W, Mohr J, Hellen P, Zoll B, Pauli S, Schmidt J. Novel fukutin mutations in limb-girdle muscular dystrophy type 2M with childhood onset. Neurol Genet 2017; 3:e167. [PMID: 28785732 PMCID: PMC5524525 DOI: 10.1212/nxg.0000000000000167] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2017] [Accepted: 04/28/2017] [Indexed: 11/15/2022]
Affiliation(s)
- Mateja Smogavec
- Institute of Human Genetics (M.S., B.Z., S.P.), Department of Neurology (J.Z., J.S.), and Department of Neuroradiology (P.H.), University Medical Center Göttingen; Department of Human Genetics (W.K.), University of Würzburg; and CeGaT GmbH und Praxis für Humangenetik (J.M.), Tübingen, Germany
| | - Jana Zschüntzsch
- Institute of Human Genetics (M.S., B.Z., S.P.), Department of Neurology (J.Z., J.S.), and Department of Neuroradiology (P.H.), University Medical Center Göttingen; Department of Human Genetics (W.K.), University of Würzburg; and CeGaT GmbH und Praxis für Humangenetik (J.M.), Tübingen, Germany
| | - Wolfram Kress
- Institute of Human Genetics (M.S., B.Z., S.P.), Department of Neurology (J.Z., J.S.), and Department of Neuroradiology (P.H.), University Medical Center Göttingen; Department of Human Genetics (W.K.), University of Würzburg; and CeGaT GmbH und Praxis für Humangenetik (J.M.), Tübingen, Germany
| | - Julia Mohr
- Institute of Human Genetics (M.S., B.Z., S.P.), Department of Neurology (J.Z., J.S.), and Department of Neuroradiology (P.H.), University Medical Center Göttingen; Department of Human Genetics (W.K.), University of Würzburg; and CeGaT GmbH und Praxis für Humangenetik (J.M.), Tübingen, Germany
| | - Peter Hellen
- Institute of Human Genetics (M.S., B.Z., S.P.), Department of Neurology (J.Z., J.S.), and Department of Neuroradiology (P.H.), University Medical Center Göttingen; Department of Human Genetics (W.K.), University of Würzburg; and CeGaT GmbH und Praxis für Humangenetik (J.M.), Tübingen, Germany
| | - Barbara Zoll
- Institute of Human Genetics (M.S., B.Z., S.P.), Department of Neurology (J.Z., J.S.), and Department of Neuroradiology (P.H.), University Medical Center Göttingen; Department of Human Genetics (W.K.), University of Würzburg; and CeGaT GmbH und Praxis für Humangenetik (J.M.), Tübingen, Germany
| | - Silke Pauli
- Institute of Human Genetics (M.S., B.Z., S.P.), Department of Neurology (J.Z., J.S.), and Department of Neuroradiology (P.H.), University Medical Center Göttingen; Department of Human Genetics (W.K.), University of Würzburg; and CeGaT GmbH und Praxis für Humangenetik (J.M.), Tübingen, Germany
| | - Jens Schmidt
- Institute of Human Genetics (M.S., B.Z., S.P.), Department of Neurology (J.Z., J.S.), and Department of Neuroradiology (P.H.), University Medical Center Göttingen; Department of Human Genetics (W.K.), University of Würzburg; and CeGaT GmbH und Praxis für Humangenetik (J.M.), Tübingen, Germany
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8
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Massalska D, Zimowski JG, Bijok J, Kucińska-Chahwan A, Łusakowska A, Jakiel G, Roszkowski T. Prenatal diagnosis of congenital myopathies and muscular dystrophies. Clin Genet 2016; 90:199-210. [PMID: 27197572 DOI: 10.1111/cge.12801] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2016] [Revised: 05/05/2016] [Accepted: 05/08/2016] [Indexed: 12/14/2022]
Abstract
Congenital myopathies and muscular dystrophies constitute a genetically and phenotypically heterogeneous group of rare inherited diseases characterized by muscle weakness and atrophy, motor delay and respiratory insufficiency. To date, curative care is not available for these diseases, which may severely affect both life-span and quality of life. We discuss prenatal diagnosis and genetic counseling for families at risk, as well as diagnostic possibilities in sporadic cases.
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Affiliation(s)
- D Massalska
- Department of Obstetrics and Gynecology, Centre of Postgraduate Medical Education, Warsaw, Poland
| | - J G Zimowski
- Department of Genetics, Institute of Psychiatry and Neurology, Warsaw, Poland
| | - J Bijok
- Department of Obstetrics and Gynecology, Centre of Postgraduate Medical Education, Warsaw, Poland
| | - A Kucińska-Chahwan
- Department of Obstetrics and Gynecology, Centre of Postgraduate Medical Education, Warsaw, Poland
| | - A Łusakowska
- Department of Neurology, Medical University of Warsaw, Poland
| | - G Jakiel
- Department of Obstetrics and Gynecology, Centre of Postgraduate Medical Education, Warsaw, Poland
| | - T Roszkowski
- Department of Obstetrics and Gynecology, Centre of Postgraduate Medical Education, Warsaw, Poland
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Founder mutation causes classical Fukuyama congenital muscular dystrophy (FCMD) in Chinese patients. Brain Dev 2015; 37:880-6. [PMID: 25814170 DOI: 10.1016/j.braindev.2015.02.010] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/12/2014] [Revised: 02/08/2015] [Accepted: 02/26/2015] [Indexed: 01/24/2023]
Abstract
PURPOSE Fukuyama congenital muscular dystrophy (FCMD) is a congenital muscular dystrophy rarely reported outside Japan. Here, we report three patients with Fukuyama congenital muscular dystrophy (FCMD) in China who shared a similar clinical phenotype and 3-kb insertion in the FKTN 3' untranslated region. METHODS Immunofluorescence staining was undertaken on muscle biopsies from three patients using alpha dystroglycan antibody (IIH6). Genomic DNA from patients and parents was extracted from peripheral blood leukocytes. Polymerase chain reaction and DNA sequencing were employed to analyze the exons and surrounding intron sequences of the fukutin (FKTN) gene to detect mutations. Haplotype analysis was also performed on each patient and their parents. RESULTS All patients had delayed mental and motor development, febrile convulsions, muscle weakness, and moderate to significant raised levels of serum creatine kinase (7000-11,160 U/L, 25-60×normal). Brain MRI scans showed micropolygyria and extensive dysplasia in the white matter and brainstem. Electromyography revealed myopathic changes. Muscle immunofluorescence studies demonstrated reduced IIH6 staining. Genetic testing showed compound heterozygous mutations of FKTN. Cases 1 and 2 had a c.139C>T (p.Arg47(∗)) heterozygous mutation. Case 3 had a c.346C>T (p.Gln116(∗)) heterozygous mutation. CONCLUSION All patients had a heterozygous 3-kb insertion in the FKTN 3' untranslated region. Haplotype analyses suggested that these patients had the same haplotype as Japanese patients.
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Matsui M, Endo T, Matsumura T, Saito T, Fujimura H. [A case of limb-girdle muscular dystrophy 2M diagnosed by the occurence of dilated cardiomyopathy]. Rinsho Shinkeigaku 2015; 55:585-8. [PMID: 26050665 DOI: 10.5692/clinicalneurol.cn-000686] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
We report a 24-year-old Japanese man initially suspected to have Becker's muscular dystrophy at the age of 6 years, because of a high level of creatine kinase in serum, though he discontinued visiting the hospital. At the age of 23, he was admitted to the hospital for severe dilated cardiomyopathy, and subsequently diagnosed with limb-girdle muscular dystrophy2M (LGMD2M) based on muscle biopsy and gene analysis. It was recently reported that some patients with fukutinopathy develop LGMD. Most of the cases reported in Japan showed mild skeletal muscle involvement despite serious cardiomyopathy, which may sometimes the initial symptom of the disease. Since muscular dystrophy patients can develop severe cardiac failure, irrespective of the severity of skeletal muscle involvement, regular examinations of cardiopulmonary function are necessary.
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Affiliation(s)
- Misa Matsui
- Department of Neurology, National Hospital Organization Toneyama National Hospital
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NIGRO VINCENZO, SAVARESE MARCO. Genetic basis of limb-girdle muscular dystrophies: the 2014 update. ACTA MYOLOGICA : MYOPATHIES AND CARDIOMYOPATHIES : OFFICIAL JOURNAL OF THE MEDITERRANEAN SOCIETY OF MYOLOGY 2014; 33:1-12. [PMID: 24843229 PMCID: PMC4021627] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
Limb-girdle muscular dystrophies (LGMD) are a highly heterogeneous group of muscle disorders, which first affect the voluntary muscles of the hip and shoulder areas. The definition is highly descriptive and less ambiguous by exclusion: non-Xlinked, non-FSH, non-myotonic, non-distal, nonsyndromic, and non-congenital. At present, the genetic classification is becoming too complex, since the acronym LGMD has also been used for a number of other myopathic disorders with overlapping phenotypes. Today, the list of genes to be screened is too large for the gene-by-gene approach and it is well suited for targeted next generation sequencing (NGS) panels that should include any gene that has been so far associated with a clinical picture of LGMD. The present review has the aim of recapitulating the genetic basis of LGMD ordering and of proposing a nomenclature for the orphan forms. This is useful given the pace of new discoveries. Thity-one loci have been identified so far, eight autosomal dominant and 23 autosomal recessive. The dominant forms (LGMD1) are: LGMD1A (myotilin), LGMD1B (lamin A/C), LGMD1C (caveolin 3), LGMD1D (DNAJB6), LGMD1E (desmin), LGMD1F (transportin 3), LGMD1G (HNRPDL), LGMD1H (chr. 3). The autosomal recessive forms (LGMD2) are: LGMD2A (calpain 3), LGMD2B (dysferlin), LGMD2C (γ sarcoglycan), LGMD2D (α sarcoglycan), LGMD2E (β sarcoglycan), LGMD2F (δ sarcoglycan), LGMD2G (telethonin), LGMD2H (TRIM32), LGMD2I (FKRP), LGMD2J (titin), LGMD2K (POMT1), LGMD2L (anoctamin 5), LGMD2M (fukutin), LGMD2N (POMT2), LGMD2O (POMTnG1), LGMD2P (dystroglycan), LGMD2Q (plectin), LGMD2R (desmin), LGMD2S (TRAPPC11), LGMD2T (GMPPB), LGMD2U (ISPD), LGMD2V (Glucosidase, alpha ), LGMD2W (PINCH2).
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Affiliation(s)
- VINCENZO NIGRO
- Address for correspondence: Vincenzo Nigro, via Luigi De Crecchio 7, 80138 Napoli, Italy; Telethon Institute of Genetics and Medicine (TIGEM), via Pietro Castellino 111, 80131 Napoli, Italy. - E-mail:
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12
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Ismail S, Schaffer AE, Rosti RO, Gleeson JG, Zaki MS. Novel mutation in the fukutin gene in an Egyptian family with Fukuyama congenital muscular dystrophy and microcephaly. Gene 2014; 539:279-82. [PMID: 24530477 DOI: 10.1016/j.gene.2014.01.070] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2013] [Revised: 01/15/2014] [Accepted: 01/22/2014] [Indexed: 12/30/2022]
Abstract
Fukuyama-type congenital muscular dystrophy (FCMD, MIM#253800) is an autosomal recessive disorder characterized by severe muscular dystrophy associated with brain malformations. FCMD is the second most common form of muscular dystrophy after Duchenne muscular dystrophy and one of the most common autosomal recessive diseases among the Japanese population, and yet few patients outside of Japan had been reported with this disorder. We report the first known Egyptian patient with FCMD, established by clinical features of generalized weakness, pseudohypertrophy of calf muscles, progressive joint contractures, severe scoliosis, elevated serum creatine kinase level, myopathic electrodiagnostic changes, brain MRI with cobblestone complex, and mutation in the fukutin gene. In addition, our patient displayed primary microcephaly, not previously reported associated with fukutin mutations. Our results expand the geographic and clinical spectrum of fukutin mutations.
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Affiliation(s)
- Samira Ismail
- Clinical Genetics Department, Human Genetics and Genome Research Division, National Research Centre, Cairo 12311, Egypt
| | - Ashleigh E Schaffer
- Howard Hughes Medical Institute, University of California, San Diego, La Jolla, CA 92093, USA
| | - Rasim O Rosti
- Howard Hughes Medical Institute, University of California, San Diego, La Jolla, CA 92093, USA
| | - Joseph G Gleeson
- Howard Hughes Medical Institute, University of California, San Diego, La Jolla, CA 92093, USA
| | - Maha S Zaki
- Clinical Genetics Department, Human Genetics and Genome Research Division, National Research Centre, Cairo 12311, Egypt.
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Novel mutations in the fukutin gene in a boy with asymptomatic hyperCKemia. Neuromuscul Disord 2013; 23:1010-5. [DOI: 10.1016/j.nmd.2013.09.010] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2013] [Revised: 09/03/2013] [Accepted: 09/23/2013] [Indexed: 11/17/2022]
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A new mutation of the fukutin gene causing late-onset limb girdle muscular dystrophy. Neuromuscul Disord 2013; 23:562-7. [DOI: 10.1016/j.nmd.2013.04.006] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2012] [Revised: 04/10/2013] [Accepted: 04/30/2013] [Indexed: 02/03/2023]
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Arnold WD, Flanigan KM. A practical approach to molecular diagnostic testing in neuromuscular diseases. Phys Med Rehabil Clin N Am 2013; 23:589-608. [PMID: 22938877 DOI: 10.1016/j.pmr.2012.06.002] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Molecular diagnosis is an important aspect in the care of patients with neuromuscular disorders. Because of the rapidly evolving nature of the field, the approach to obtaining a molecular diagnosis may be challenging. This article provides a general approach to molecular diagnostic testing while reviewing the principles of genetics and genetic disorders and the indications and limitations of testing methods in common hereditary neuromuscular disorders.
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Affiliation(s)
- W David Arnold
- Division of Neuromuscular Disorders, Department of Neurology, Wexner Medical Center at the Ohio State University, The Ohio State University, 395 W. 12th Avenue, 7th Floor, Columbus, OH 43210, USA.
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Molecular diagnosis of congenital muscular dystrophies with defective glycosylation of alpha-dystroglycan using next-generation sequencing technology. Neuromuscul Disord 2013; 23:337-44. [PMID: 23453855 DOI: 10.1016/j.nmd.2013.01.007] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2012] [Revised: 01/08/2013] [Accepted: 01/15/2013] [Indexed: 01/29/2023]
Abstract
Targeted resequencing using next-generation sequencing technology is being rapidly applied to the molecular diagnosis of human genetic diseases. The group of muscular dystrophies may be an appropriate candidate for this approach because these diseases exhibit genotype-phenotype heterogeneity. To perform a proof-of-concept study, we selected four patients with congenital muscular dystrophies with defective glycosylation of alpha-dystroglycan. A custom-solution-based target enrichment kit was designed to capture whole-genic regions of the 26 muscular-dystrophy-related genes, including six genes implicated in alpha-dystroglycanopathies. Although approximately 95% of both coding and noncoding regions were covered with at least 15-read depth, parts of the coding exons of FKRP and POMT2 were insufficiently covered. Homozygous and compound heterozygous POMGnT1 mutations were found in two patients. Two novel noncoding variants of FKTN were identified in one patient who had a retrotransposon insertion mutation of FKTN in only one allele. The current targeted resequencing strategy yielded promising results for the extension of this method to other muscular dystrophies. As suboptimal coverage in a small subset of coding regions may affect the sensitivity of the method, complementary Sanger sequencing may be required.
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Abstract
Glycosylation is an essential process by which sugars are attached to proteins and lipids. Complete lack of glycosylation is not compatible with life. Because of the widespread function of glycosylation, inherited disorders of glycosylation are multisystemic. Since the identification of the first defect on N-linked glycosylation in the 1980s, there are over 40 different congenital protein hypoglycosylation diseases. This review will include defects of N-linked glycosylation, O-linked glycosylation and disorders of combined N- and O-linked glycosylation.
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Affiliation(s)
- Susan E Sparks
- Department of Pediatrics, Levine Children's Hospital at Carolinas Medical Center, Charlotte, NC, USA; Department of Pediatrics, University of North Carolina School of Medicine, Chapel Hill, NC, USA
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Abstract
The secondary α-dystroglycanopathies usually present in infancy as congenital muscular dystrophies but may manifest later in childhood or adult life (limb-girdle muscular dystrophy (LGMD) 2I, LGMD2K, LGMD2M, LGMD2N, and LGMD2O). Patients with telethoninopathy (LGMD2B) may present with mainly proximal or distal lower extremity weakness, and notably the muscle biopsies may demonstrate rimmed vacuoles. LGMD2L is caused by newly described mutations in ANO5 and can sometimes present with distal weakness resembling Miyoshi myopathy.
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Gupta V, Kawahara G, Gundry SR, Chen AT, Lencer WI, Zhou Y, Zon LI, Kunkel LM, Beggs AH. The zebrafish dag1 mutant: a novel genetic model for dystroglycanopathies. Hum Mol Genet 2011; 20:1712-25. [PMID: 21296866 DOI: 10.1093/hmg/ddr047] [Citation(s) in RCA: 86] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
In a forward genetic approach to identify novel genes for congenital muscle diseases, a zebrafish mutant, designated patchytail, was identified that exhibits degenerating muscle fibers with impaired motility behavior. Genetic mapping identified a genomic locus containing the zebrafish ortholog of the dystroglycan gene (DAG1). Patchytail fish contain a point mutation (c.1700T>A) in dag1, resulting in a missense change p.V567D. This change is associated with reduced transcripts and a complete absence of protein. The absence of α-dystroglycan and β-dystroglycan caused destabilization of dystroglycan complex, resulting in membrane damages. Membrane damage was localized on the extracellular matrix at myosepta as well as basement membrane between adjacent myofibers. These studies also identified structural abnormalities in triads at 3 days post fertilization (dpf) of dystroglycan-deficient muscles, significantly preceding sarcolemmal damage that becomes evident at 7 dpf. Immunofluorescence studies identified a subpopulation of dystroglycan that is expressed at t-tubules in normal skeletal muscles. In dag1-mutated fish, smaller and irregular-shaped t-tubule vesicles, as well as highly disorganized terminal cisternae of sarcoplasmic reticulum, were common. In addition to skeletal muscle defects, dag1-mutated fish have brain abnormalities and ocular defects in posterior as well as anterior chambers. These phenotypes of dystroglycan-deficient fish are highly reminiscent of the phenotypes observed in the human conditions muscle-eye-brain disease and Walker-Warburg syndrome. This animal model will provide unique opportunities in the understanding of biological functions of dystroglycan in a wide range of dystroglycanopathies, as disruption of this gene in higher vertebrates results in early embryonic lethality.
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Affiliation(s)
- Vandana Gupta
- Genomics Program and Division of Genetics, The Manton Center for Orphan Disease Research, Children's Hospital Boston, Boston, MA 02115, USA
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Yis U, Uyanik G, Heck PB, Smitka M, Nobel H, Ebinger F, Dirik E, Feng L, Kurul SH, Brocke K, Unalp A, Özer E, Cakmakci H, Sewry C, Cirak S, Muntoni F, Hehr U, Morris-Rosendahl DJ. Fukutin mutations in non-Japanese patients with congenital muscular dystrophy: less severe mutations predominate in patients with a non-Walker-Warburg phenotype. Neuromuscul Disord 2010; 21:20-30. [PMID: 20961758 DOI: 10.1016/j.nmd.2010.08.007] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2010] [Accepted: 08/27/2010] [Indexed: 11/16/2022]
Abstract
Six genes including POMT1, POMT2, POMGNT1, FKRP, Fukutin (FKTN) and LARGE encode proteins involved in the glycosylation of α-dystroglycan (α-DG). Abnormal glycosylation of α-DG is a common finding in Walker-Warburg syndrome (WWS), muscle-eye-brain disease (MEB), Fukuyama congenital muscular dystrophy (FCMD), congenital muscular dystrophy types 1C and 1D and some forms of autosomal recessive limb-girdle muscular dystrophy (LGMD2I, LGMD2K, LGMD2M), and is associated with mutations in the above genes. FCMD, caused by mutations in Fukutin (FKTN), is most frequent in Japan, but an increasing number of FKTN mutations are being reported outside of Japan. We describe four new patients with FKTN mutations and phenotypes ranging from: severe WWS in a Greek-Croatian patient, to congenital muscular dystrophy and cobblestone lissencephaly resembling MEB-FCMD in two Turkish patients, and limb-girdle muscular dystrophy and no mental retardation in a German patient. Four of the five different FKTN mutations have not been previously described.
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Affiliation(s)
- Uluc Yis
- Gaziantep Children's Hospital, Department of Pediatric Neurology, Gaziantep, Turkey
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Kondo Y, Mori-Yoshimura M, Hayashi YK, Oya Y, Satoh N, Nishino I, Murata M. [Limb-girdle muscular dystrophy type 2M with adult-onset loss of ambulation. A case report]. Rinsho Shinkeigaku 2010; 50:661-665. [PMID: 20960933 DOI: 10.5692/clinicalneurol.50.661] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
We report a 29-year-old man with limb-girdle muscular dystrophy type 2M (LGMD2M) caused by a compound heterozygous mutation of 3-kb insertion in the 3'-untranslated region and c.1073A > C (p.Q358P) mutation in exon 9 in FKTN. He had been diagnosed since childhood as having Becker muscular dystrophy based on limb-girdle muscle weakness and calf muscle hypertrophy. Loss of ambulation occurred at age 26 years and cardiomyopathy was noted one year later. Muscle biopsy at age 29 revealed dystrophic changes with loss of immunoreactivity to alpha-dystroglycan (alpha-DG), which prompted us to analyze FKTN and subsequent establishment of the diagnosis of LGMD2M. Brain MRI revealed hypoplasia of the right cerebellar hemisphere and tonsil. Dysplastic part was present in the lower medial part of the hypoplastic hemisphare, which was bordered by a deep cleft. Previously reported LGMD2M patients had mild or minimal muscle weakness in addition to dilated cardiomyopathy. In contrast, our patient had more severe skeletal muscle weakness and loss of ambulation. Treatment with 3-blockers or angiotensin II converting enzyme blockers has been reported to be efficacious for cardiomyopathy in patients with muscular dystrophy. The precise diagnosis should be established early in patients with muscular dystrophy complicated with cardiomyopathy.
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Affiliation(s)
- Yoshiyuki Kondo
- Department of Neurology National Center Hospital, National Center of Neurology and Psychiatry
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Sciandra F, Bozzi M, Morlacchi S, Galtieri A, Giardina B, Brancaccio A. Mutagenesis at the alpha-beta interface impairs the cleavage of the dystroglycan precursor. FEBS J 2009; 276:4933-45. [PMID: 19694806 DOI: 10.1111/j.1742-4658.2009.07196.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
The interaction between a-dystroglycan (alpha-DG) and beta-dystroglycan (beta-DG), the two constituent subunits of the adhesion complex dystroglycan, is crucial in maintaining the integrity of the dystrophin-glycoprotein complex. The importance of the alpha-beta interface can be seen in the skeletal muscle of humans affected by severe conditions, such as Duchenne muscular dystrophy, where the alpha-beta interaction can be secondarily weakened or completely lost, causing sarcolemmal instability and muscular necrosis. The reciprocal binding epitopes of the two subunits reside within the C-terminus of alpha-DG and the ectodomain of beta-DG. As no ultimate structural data are yet available on the alpha-beta interface, site-directed mutagenesis was used to identify which specific amino acids are involved in the interaction. A previous alanine-scanning analysis of the recombinant beta-DG ectodomain allowed the identification of two phenylalanines important for alpha-DG binding, namely F692 and F718. In this article, similar experiments performed on the alpha-DG C-terminal domain pinpointed two residues, G563 and P565, as possible binding counterparts of the two beta-DG phenylalanines. In 293-Ebna cells, the introduction of alanine residues instead of F692, F718, G563 and P565 prevented the cleavage of the DG precursor that liberates alpha- and beta-DG, generating a pre-DG of about 160 kDa. This uncleaved pre-DG tetramutant is properly targeted at the cell membrane, is partially glycosylated and still binds laminin in pull-down assays. These data reinforce the notion that DG processing and its membrane targeting are two independent processes, and shed new light on the molecular mechanism that drives the maturation of the DG precursor.
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Affiliation(s)
- Francesca Sciandra
- Istituto di Chimica del Riconoscimento Molecolare (CNR), c/o Istituto di Biochimica e Biochimica Clinica, Università Cattolica del Sacro Cuore, Rome, Italy
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