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Buvoli M, Wilson GC, Buvoli A, Gugel JF, Hau A, Bönnemann CG, Paradas C, Ryba DM, Woulfe KC, Walker LA, Buvoli T, Ochala J, Leinwand LA. A Laing distal myopathy-associated proline substitution in the β-myosin rod perturbs myosin cross-bridging activity. J Clin Invest 2024; 134:e172599. [PMID: 38690726 PMCID: PMC11060730 DOI: 10.1172/jci172599] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2023] [Accepted: 03/11/2024] [Indexed: 05/03/2024] Open
Abstract
Proline substitutions within the coiled-coil rod region of the β-myosin gene (MYH7) are the predominant mutations causing Laing distal myopathy (MPD1), an autosomal dominant disorder characterized by progressive weakness of distal/proximal muscles. We report that the MDP1 mutation R1500P, studied in what we believe to be the first mouse model for the disease, adversely affected myosin motor activity despite being in the structural rod domain that directs thick filament assembly. Contractility experiments carried out on isolated mutant muscles, myofibrils, and myofibers identified muscle fatigue and weakness phenotypes, an increased rate of actin-myosin detachment, and a conformational shift of the myosin heads toward the more reactive disordered relaxed (DRX) state, causing hypercontractility and greater ATP consumption. Similarly, molecular analysis of muscle biopsies from patients with MPD1 revealed a significant increase in sarcomeric DRX content, as observed in a subset of myosin motor domain mutations causing hypertrophic cardiomyopathy. Finally, oral administration of MYK-581, a small molecule that decreases the population of heads in the DRX configuration, significantly improved the limited running capacity of the R1500P-transgenic mice and corrected the increased DRX state of the myofibrils from patients. These studies provide evidence of the molecular pathogenesis of proline rod mutations and lay the groundwork for the therapeutic advancement of myosin modulators.
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Affiliation(s)
- Massimo Buvoli
- Department of Molecular, Cellular and Developmental Biology, and
- BioFrontiers Institute, Department of Molecular, Cellular and Developmental Biology, University of Colorado, Boulder, Colorado, USA
| | - Genevieve C.K. Wilson
- Department of Molecular, Cellular and Developmental Biology, and
- BioFrontiers Institute, Department of Molecular, Cellular and Developmental Biology, University of Colorado, Boulder, Colorado, USA
| | - Ada Buvoli
- Department of Molecular, Cellular and Developmental Biology, and
- BioFrontiers Institute, Department of Molecular, Cellular and Developmental Biology, University of Colorado, Boulder, Colorado, USA
| | - Jack F. Gugel
- Department of Molecular, Cellular and Developmental Biology, and
- BioFrontiers Institute, Department of Molecular, Cellular and Developmental Biology, University of Colorado, Boulder, Colorado, USA
| | - Abbi Hau
- Centre of Human and Applied Physiological Sciences, School of Basic and Medical Biosciences, Faculty of Life Sciences and Medicine, and
- Randall Centre for Cell and Molecular Biophysics, School of Basic and Medical Biosciences, Faculty of Life Sciences and Medicine, Guy’s Campus, King’s College London, London, United Kingdom
| | - Carsten G. Bönnemann
- Neuromuscular and Neurogenetic Disorders of Childhood Section, National Institute of Neurological Disorders and Stroke (NINDS), NIH, Bethesda, Maryland, USA
| | - Carmen Paradas
- Neuromuscular Unit, Department of Neurology, Instituto de Biomedicina de Sevilla (IBIS), Hospital Universitario Virgen del Rocío/CSIC/Universidad de Sevilla, Sevilla, Spain
| | | | - Kathleen C. Woulfe
- Division of Cardiology, Department of Medicine, University of Colorado, Denver, Colorado, USA
| | - Lori A. Walker
- Division of Cardiology, Department of Medicine, University of Colorado, Denver, Colorado, USA
| | - Tommaso Buvoli
- Department of Mathematics, Tulane University, New Orleans, Louisiana, USA
| | - Julien Ochala
- Centre of Human and Applied Physiological Sciences, School of Basic and Medical Biosciences, Faculty of Life Sciences and Medicine, and
- Randall Centre for Cell and Molecular Biophysics, School of Basic and Medical Biosciences, Faculty of Life Sciences and Medicine, Guy’s Campus, King’s College London, London, United Kingdom
- Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Leslie A. Leinwand
- Department of Molecular, Cellular and Developmental Biology, and
- BioFrontiers Institute, Department of Molecular, Cellular and Developmental Biology, University of Colorado, Boulder, Colorado, USA
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2
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Gao Y, Peng L, Zhao C. MYH7 in cardiomyopathy and skeletal muscle myopathy. Mol Cell Biochem 2024; 479:393-417. [PMID: 37079208 DOI: 10.1007/s11010-023-04735-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2023] [Accepted: 04/07/2023] [Indexed: 04/21/2023]
Abstract
Myosin heavy chain gene 7 (MYH7), a sarcomeric gene encoding the myosin heavy chain (myosin-7), has attracted considerable interest as a result of its fundamental functions in cardiac and skeletal muscle contraction and numerous nucleotide variations of MYH7 are closely related to cardiomyopathy and skeletal muscle myopathy. These disorders display significantly inter- and intra-familial variability, sometimes developing complex phenotypes, including both cardiomyopathy and skeletal myopathy. Here, we review the current understanding on MYH7 with the aim to better clarify how mutations in MYH7 affect the structure and physiologic function of sarcomere, thus resulting in cardiomyopathy and skeletal muscle myopathy. Importantly, the latest advances on diagnosis, research models in vivo and in vitro and therapy for precise clinical application have made great progress and have epoch-making significance. All the great advance is discussed here.
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Affiliation(s)
- Yuan Gao
- Department of Pediatrics, Qilu Hospital of Shandong University, Jinan, 250012, China
| | - Lu Peng
- Department of Pediatrics, Qilu Hospital of Shandong University, Jinan, 250012, China
| | - Cuifen Zhao
- Department of Pediatrics, Qilu Hospital of Shandong University, Jinan, 250012, China.
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3
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Younger DS. Childhood muscular dystrophies. HANDBOOK OF CLINICAL NEUROLOGY 2023; 195:461-496. [PMID: 37562882 DOI: 10.1016/b978-0-323-98818-6.00024-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/12/2023]
Abstract
Infancy- and childhood-onset muscular dystrophies are associated with a characteristic distribution and progression of motor dysfunction. The underlying causes of progressive childhood muscular dystrophies are heterogeneous involving diverse genetic pathways and genes that encode proteins of the plasma membrane, extracellular matrix, sarcomere, and nuclear membrane components. The prototypical clinicopathological features in an affected child may be adequate to fully distinguish it from other likely diagnoses based on four common features: (1) weakness and wasting of pelvic-femoral and scapular muscles with involvement of heart muscle; (2) elevation of serum muscle enzymes in particular serum creatine kinase; (3) necrosis and regeneration of myofibers; and (4) molecular neurogenetic assessment particularly utilizing next-generation sequencing of the genome of the likeliest candidates genes in an index case or family proband. A number of different animal models of therapeutic strategies have been developed for gene transfer therapy, but so far these techniques have not yet entered clinical practice. Treatment remains for the most part symptomatic with the goal of ameliorating locomotor and cardiorespiratory manifestations of the disease.
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Affiliation(s)
- David S Younger
- Department of Clinical Medicine and Neuroscience, CUNY School of Medicine, New York, NY, United States; Department of Medicine, Section of Internal Medicine and Neurology, White Plains Hospital, White Plains, NY, United States.
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4
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Yu M, Zhu Y, Lu Y, Lv H, Zhang W, Yuan Y, Wang Z. Clinical features and genotypes of Laing distal myopathy in a group of Chinese patients, with in-frame deletions of MYH7 as common mutations. Orphanet J Rare Dis 2020; 15:344. [PMID: 33298082 PMCID: PMC7727133 DOI: 10.1186/s13023-020-01626-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2020] [Accepted: 11/26/2020] [Indexed: 11/24/2022] Open
Abstract
Background Laing distal myopathy is a rare autosomal dominant inherited distal myopathy caused by mutations of the MYH7 gene affecting mainly the rod region. We described the clinical features, muscle MRI and pathological changes as well as genetic mutations in a group of Chinese patients with Laing distal myopathy. Results Six patients with the confirmed diagnoses of Laing distal myopathy were recruited. Ankle dorsiflexion and finger extension weakness, as well as neck flexion weakness were common in our patients. Myopathic as well as neurogenic lesions were suggested by electromyography in different patients. Respiratory abnormality of sleep apnea was detected in two of our patients stressing the necessity of close respiratory monitoring in this disease. Muscle MRIs showed similar features of concentric fatty infiltration of anterior thigh muscles together with early involvement of tibialis anterior and extensor hallucis longus. However, muscle pathological presentations were varied depending on the biopsied muscles and the severity of the disease. In-frame deletions of the MYH7 gene made up 3/4 of mutations in our patients, suggesting that these are common mutations of Laing distal myopathy. Conclusions Our study further expanded the phenotypes and genotypes of Laing distal myopathy. In-frame deletions of the MYH7 gene are common causes of Laing distal myopathy.
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Affiliation(s)
- Meng Yu
- Department of Neurology, Peking University First Hospital, No. 8 Xishiku Street, Beijing, 100034, China
| | - Ying Zhu
- Department of Radiology, Peking University First Hospital, Beijing, China
| | - Yuanyuan Lu
- Department of Neurology, Peking University First Hospital, No. 8 Xishiku Street, Beijing, 100034, China
| | - He Lv
- Department of Neurology, Peking University First Hospital, No. 8 Xishiku Street, Beijing, 100034, China
| | - Wei Zhang
- Department of Neurology, Peking University First Hospital, No. 8 Xishiku Street, Beijing, 100034, China
| | - Yun Yuan
- Department of Neurology, Peking University First Hospital, No. 8 Xishiku Street, Beijing, 100034, China
| | - Zhaoxia Wang
- Department of Neurology, Peking University First Hospital, No. 8 Xishiku Street, Beijing, 100034, China.
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5
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Muelas N, Frasquet M, Más-Estellés F, Martí P, Martínez-Vicente L, Sevilla T, Azorín I, Poyatos-García J, Argente-Escrig H, Vílchez R, Vázquez-Costa JF, Bataller L, Vilchez JJ. A study of the phenotypic variability and disease progression in Laing myopathy through the evaluation of muscle imaging. Eur J Neurol 2020; 28:1356-1365. [PMID: 33151602 DOI: 10.1111/ene.14630] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2020] [Revised: 09/25/2020] [Accepted: 10/22/2020] [Indexed: 01/20/2023]
Abstract
BACKGROUND Laing myopathy is characterized by broad clinical and pathological variability. They are limited in number and protocol of study. We aimed to delineate muscle imaging profiles and validate imaging analysis as an outcome measure. METHODS This was a cross-sectional and longitudinal cohort study. Data from clinical, functional and semi-quantitative muscle imaging (60 magnetic resonance imaging [MRI] and six computed tomography scans) were studied. Hierarchical analysis, graphic heatmap representation and correlation between imaging and clinical data using Bayesian statistics were carried out. RESULTS The study cohort comprised 42 patients from 13 families harbouring five MYH7 mutations. The cohort had a wide range of ages, age at onset, disease duration, and myopathy extension and Gardner-Medwin and Walton (GMW) functional scores. Intramuscular fat was evident in all but two asymptomatic/pauci-symptomatic patients. Anterior leg compartment muscles were the only affected muscles in 12% of the patients. Widespread extension to the thigh, hip, paravertebral and calf muscles and, less frequently, the scapulohumeral muscles was commonly observed, depicting distinct patterns and rates of progression. Foot muscles were involved in 40% of patients, evolving in parallel to other regions with absence of a disto-proximal gradient. Whole cumulative imaging score, ranging from 0 to 2.9 out of 4, was associated with disease duration and with myopathy extension and GMW scales. Follow-up MRI studies in 24 patients showed significant score progression at a variable rate. CONCLUSIONS We confirmed that the anterior leg compartment is systematically affected in Laing myopathy and may represent the only manifestation of this disorder. However, widespread muscle involvement in preferential but variable and not distance-dependent patterns was frequently observed. Imaging score analysis is useful to categorize patients and to follow disease progression over time.
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Affiliation(s)
- Nuria Muelas
- Neuromuscular Diseases Unit, Neurology Department, Hospital Universitari I Politècnic La Fe, Valencia, Spain.,Neuromuscular Reference Centre, ERN-EURO-NMD, Valencia, Spain.,Neuromuscular and Ataxias Research Group, Instituto de Investigación Sanitaria La Fe, Valencia, Spain.,Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER, U763, Valencia, Spain
| | - Marina Frasquet
- Neuromuscular Diseases Unit, Neurology Department, Hospital Universitari I Politècnic La Fe, Valencia, Spain.,Neuromuscular Reference Centre, ERN-EURO-NMD, Valencia, Spain.,Neuromuscular and Ataxias Research Group, Instituto de Investigación Sanitaria La Fe, Valencia, Spain
| | - Fernando Más-Estellés
- Ascires, Neuroradiology Section, Área Clínica de Imagen Médica, Hospital Universitari I Politècnic La Fe, Valencia, Spain
| | - Pilar Martí
- Neuromuscular and Ataxias Research Group, Instituto de Investigación Sanitaria La Fe, Valencia, Spain.,Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER, U763, Valencia, Spain
| | - Laura Martínez-Vicente
- Neuromuscular Diseases Unit, Neurology Department, Hospital Universitari I Politècnic La Fe, Valencia, Spain.,Neuromuscular Reference Centre, ERN-EURO-NMD, Valencia, Spain.,Neuromuscular and Ataxias Research Group, Instituto de Investigación Sanitaria La Fe, Valencia, Spain.,Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER, U763, Valencia, Spain
| | - Teresa Sevilla
- Neuromuscular Diseases Unit, Neurology Department, Hospital Universitari I Politècnic La Fe, Valencia, Spain.,Neuromuscular Reference Centre, ERN-EURO-NMD, Valencia, Spain.,Neuromuscular and Ataxias Research Group, Instituto de Investigación Sanitaria La Fe, Valencia, Spain.,Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER, U763, Valencia, Spain.,Department of Medicine, Universitat de València, Valencia, Spain
| | - Inmaculada Azorín
- Neuromuscular and Ataxias Research Group, Instituto de Investigación Sanitaria La Fe, Valencia, Spain.,Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER, U763, Valencia, Spain
| | - Javier Poyatos-García
- Neuromuscular and Ataxias Research Group, Instituto de Investigación Sanitaria La Fe, Valencia, Spain
| | - Herminia Argente-Escrig
- Neuromuscular Diseases Unit, Neurology Department, Hospital Universitari I Politècnic La Fe, Valencia, Spain.,Neuromuscular Reference Centre, ERN-EURO-NMD, Valencia, Spain.,Neuromuscular and Ataxias Research Group, Instituto de Investigación Sanitaria La Fe, Valencia, Spain
| | - Roger Vílchez
- Neuromuscular and Ataxias Research Group, Instituto de Investigación Sanitaria La Fe, Valencia, Spain.,Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER, U763, Valencia, Spain
| | - Juan F Vázquez-Costa
- Neuromuscular Diseases Unit, Neurology Department, Hospital Universitari I Politècnic La Fe, Valencia, Spain.,Neuromuscular Reference Centre, ERN-EURO-NMD, Valencia, Spain.,Neuromuscular and Ataxias Research Group, Instituto de Investigación Sanitaria La Fe, Valencia, Spain.,Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER, U763, Valencia, Spain.,Department of Medicine, Universitat de València, Valencia, Spain
| | - Luis Bataller
- Neuromuscular Diseases Unit, Neurology Department, Hospital Universitari I Politècnic La Fe, Valencia, Spain.,Neuromuscular Reference Centre, ERN-EURO-NMD, Valencia, Spain.,Neuromuscular and Ataxias Research Group, Instituto de Investigación Sanitaria La Fe, Valencia, Spain.,Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER, U763, Valencia, Spain.,Department of Medicine, Universitat de València, Valencia, Spain
| | - Juan J Vilchez
- Neuromuscular Diseases Unit, Neurology Department, Hospital Universitari I Politècnic La Fe, Valencia, Spain.,Neuromuscular Reference Centre, ERN-EURO-NMD, Valencia, Spain.,Neuromuscular and Ataxias Research Group, Instituto de Investigación Sanitaria La Fe, Valencia, Spain.,Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER, U763, Valencia, Spain
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6
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Abstract
Myosins constitute a superfamily of actin-based molecular motor proteins that mediates a variety of cellular activities including muscle contraction, cell migration, intracellular transport, the formation of membrane projections, cell adhesion, and cell signaling. The 12 myosin classes that are expressed in humans share sequence similarities especially in the N-terminal motor domain; however, their enzymatic activities, regulation, ability to dimerize, binding partners, and cellular functions differ. It is becoming increasingly apparent that defects in myosins are associated with diseases including cardiomyopathies, colitis, glomerulosclerosis, neurological defects, cancer, blindness, and deafness. Here, we review the current state of knowledge regarding myosins and disease.
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7
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Merlini L, Sabatelli P, Antoniel M, Carinci V, Niro F, Monetti G, Torella A, Giugliano T, Faldini C, Nigro V. Congenital myopathy with hanging big toe due to homozygous myopalladin (MYPN) mutation. Skelet Muscle 2019; 9:14. [PMID: 31133047 PMCID: PMC6535860 DOI: 10.1186/s13395-019-0199-9] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2018] [Accepted: 04/25/2019] [Indexed: 12/11/2022] Open
Abstract
Background Myopalladin (MYPN) is a component of the sarcomere that tethers nebulin in skeletal muscle and nebulette in cardiac muscle to alpha-actinin at the Z lines. Autosomal dominant MYPN mutations cause hypertrophic, dilated, or restrictive cardiomyopathy. Autosomal recessive MYPN mutations have been reported in only six families showing a mildly progressive nemaline or cap myopathy with cardiomyopathy in some patients. Case presentation A consanguineous family with congenital to adult-onset muscle weakness and hanging big toe was reported. Muscle biopsy showed minimal changes with internal nuclei, type 1 fiber predominance, and ultrastructural defects of Z line. Muscle CT imaging showed marked hypodensity of the sartorius bilaterally and MRI scattered abnormal high-intensity areas in the internal tongue muscle and in the posterior cervical muscles. Cardiac involvement was demonstrated by magnetic resonance imaging and late gadolinium enhancement. Whole exome sequencing analysis identified a homozygous loss of function single nucleotide deletion in the exon 11 of the MYPN gene in two siblings. Full-length MYPN protein was undetectable on immunoblotting, and on immunofluorescence, its localization at the Z line was missed. Conclusions This report extends the phenotypic spectrum of recessive MYPN-related myopathies showing: (1) the two patients had hanging big toe and the oldest one developed spine and hand contractures, none of these signs observed in the previously reported patients, (2) specific ultrastructural changes consisting in Z line fragmentation, but (3) no nemaline or caps on muscle pathology.
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Affiliation(s)
- Luciano Merlini
- Department of Biomedical and Neuromotor Sciences, University of Bologna, Bologna, Italy
| | - Patrizia Sabatelli
- IRCCS-Istituto Ortopedico Rizzoli, Bologna, Italy.,Institute of Molecular Genetics, National Research Council of Italy, Bologna, Italy
| | - Manuela Antoniel
- Institute of Molecular Genetics, National Research Council of Italy, Bologna, Italy
| | | | - Fabio Niro
- Division of Cardiology, Hospital St. Orsola, Bologna, Italy
| | | | - Annalaura Torella
- Dipartimento di Medicina di Precisione, Università della Campania "Luigi Vanvitelli", Naples, Italy.,Telethon Institute of Genetics and Medicine (TIGEM), Pozzuoli, Italy
| | - Teresa Giugliano
- Dipartimento di Medicina di Precisione, Università della Campania "Luigi Vanvitelli", Naples, Italy
| | - Cesare Faldini
- Department of Biomedical and Neuromotor Sciences, University of Bologna, Clinic of Orthopaedic and Traumatology, Istituto Ortopedico Rizzoli, Bologna, Italy
| | - Vincenzo Nigro
- Dipartimento di Medicina di Precisione, Università della Campania "Luigi Vanvitelli", Naples, Italy. .,Telethon Institute of Genetics and Medicine (TIGEM), Pozzuoli, Italy.
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8
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Bugiardini E, Morrow JM, Shah S, Wood CL, Lynch DS, Pitmann AM, Reilly MM, Houlden H, Matthews E, Parton M, Hanna MG, Straub V, Yousry TA. The Diagnostic Value of MRI Pattern Recognition in Distal Myopathies. Front Neurol 2018; 9:456. [PMID: 29997562 PMCID: PMC6028608 DOI: 10.3389/fneur.2018.00456] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2017] [Accepted: 05/29/2018] [Indexed: 12/14/2022] Open
Abstract
Objective: Distal myopathies are a diagnostically challenging group of diseases. We wanted to understand the value of MRI in the current clinical setting and explore the potential for optimizing its clinical application. Methods: We retrospectively audited the diagnostic workup in a distal myopathy patient cohort, reassessing the diagnosis, whilst documenting the usage of MRI. We established a literature based distal myopathies MRI pattern template and assessed its diagnostic utility in terms of sensitivity, specificity, and potential impact on the diagnostic workup. Results: Fifty-five patients were included; in 38 with a comprehensive set of data the diagnostic work-up was audited. The median time from symptoms onset to diagnosis was 12.1 years. The initial genetic diagnostic rate was 39%; 18% were misdiagnosed as neuropathies and 13% as inclusion body myositis (IBM). Based on 21 publications we established a MRI pattern template. Its overall sensitivity (50%) and specificity (32%) were low. However in some diseases (e.g., MYOT-related myopathy, TTN-HMERF) MRI correctly identified the causative gene. The number of genes suggested by MRI pattern analysis was smaller compared to clinical work up (median 1 vs. 9, p < 0.0001) but fewer genes were correctly predicted (5/10 vs. 7/10). MRI analysis ruled out IBM in all cases. Conclusion: In the diagnostic work-up of distal myopathies, MRI is useful in assisting genetic testing and avoiding misdiagnosis (IBM). The overall low sensitivity and specificity limits its generalized use when traditional single gene test methods are applied. However, in the context of next generation sequencing MRI may represent a valuable tool for interpreting complex genetic results.
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Affiliation(s)
- Enrico Bugiardini
- MRC Centre for Neuromuscular Diseases, UCL Institute of Neurology and National Hospital for Neurology and Neurosurgery, London, United Kingdom
| | - Jasper M. Morrow
- MRC Centre for Neuromuscular Diseases, UCL Institute of Neurology and National Hospital for Neurology and Neurosurgery, London, United Kingdom
| | - Sachit Shah
- Neuroradiological Academic Unit, UCL Institute of Neurology, London, United Kingdom
- Lysholm Department of Neuroradiology, National Hospital for Neurology and Neurosurgery, London, United Kingdom
| | - Claire L. Wood
- John Walton Muscular Dystrophy Research Centre, Institute of Genetic Medicine, Newcastle upon Tyne, United Kingdom
| | - David S. Lynch
- Department of Molecular Neuroscience, UCL Institute of Neurology, London, United Kingdom
| | - Alan M. Pitmann
- Department of Molecular Neuroscience, UCL Institute of Neurology, London, United Kingdom
| | - Mary M. Reilly
- MRC Centre for Neuromuscular Diseases, UCL Institute of Neurology and National Hospital for Neurology and Neurosurgery, London, United Kingdom
- Department of Molecular Neuroscience, UCL Institute of Neurology, London, United Kingdom
| | - Henry Houlden
- Department of Molecular Neuroscience, UCL Institute of Neurology, London, United Kingdom
| | - Emma Matthews
- MRC Centre for Neuromuscular Diseases, UCL Institute of Neurology and National Hospital for Neurology and Neurosurgery, London, United Kingdom
| | - Matt Parton
- MRC Centre for Neuromuscular Diseases, UCL Institute of Neurology and National Hospital for Neurology and Neurosurgery, London, United Kingdom
| | - Michael G. Hanna
- MRC Centre for Neuromuscular Diseases, UCL Institute of Neurology and National Hospital for Neurology and Neurosurgery, London, United Kingdom
- Department of Molecular Neuroscience, UCL Institute of Neurology, London, United Kingdom
| | - Volker Straub
- John Walton Muscular Dystrophy Research Centre, Institute of Genetic Medicine, Newcastle upon Tyne, United Kingdom
| | - Tarek A. Yousry
- MRC Centre for Neuromuscular Diseases, UCL Institute of Neurology and National Hospital for Neurology and Neurosurgery, London, United Kingdom
- Neuroradiological Academic Unit, UCL Institute of Neurology, London, United Kingdom
- Lysholm Department of Neuroradiology, National Hospital for Neurology and Neurosurgery, London, United Kingdom
- *Correspondence: Tarek A. Yousry
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9
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Abstract
In this article, distal myopathy syndromes are discussed. A discussion of the more traditional distal myopathies is followed by discussion of the myofibrillar myopathies. Other clinically and genetically distinctive distal myopathy syndromes usually based on single or smaller family cohorts are reviewed. Other neuromuscular disorders that are important to recognize are also considered, because they show prominent distal limb weakness.
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Affiliation(s)
- Mazen M Dimachkie
- Neuromuscular Section, Neurophysiology Division, Department of Neurology, University of Kansas Medical Center, 3901 Rainbow Boulevard, Mail Stop 2012, Kansas City, KS 66160, USA.
| | - Richard J Barohn
- Department of Neurology, University of Kansas Medical Center, 3901 Rainbow Boulevard, Mail Stop 2012, Kansas City, KS 66160, USA
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10
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Exome sequencing identifies Laing distal myopathy MYH7 mutation in a Roma family previously diagnosed with distal neuronopathy. Neuromuscul Disord 2014; 24:156-61. [DOI: 10.1016/j.nmd.2013.10.010] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2013] [Revised: 10/08/2013] [Accepted: 10/31/2013] [Indexed: 11/22/2022]
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11
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Park JM, Kim YJ, Yoo JH, Hong YB, Park JH, Koo H, Chung KW, Choi BO. A novel MYH7 mutation with prominent paraspinal and proximal muscle involvement. Neuromuscul Disord 2013; 23:580-6. [PMID: 23707328 DOI: 10.1016/j.nmd.2013.04.003] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2013] [Revised: 03/20/2013] [Accepted: 04/22/2013] [Indexed: 12/12/2022]
Abstract
Laing distal myopathy (LDM) is caused by mutations in the MYH7 gene, and known to have muscle weakness of distal limbs and neck flexors. Through whole exome sequencing, we identified a novel p.Ala1439Pro MYH7 mutation in a Korean LDM family. This missense mutation is located in more N-terminal than any reported rod domain LDM mutations. In the early stage of disease, the present patients showed similar clinical patterns to the previously described patients of LDM. However, in the later stage, fatty replacement and atrophy of paraspinal or proximal leg muscles was more severely marked than lower leg muscles, and asymmetric atrophies were observed in trapezius, subscapularis and adductor magnus muscles. Distal myopathy like LDM showed marked and predominant fatty infiltrations in paraspinal or proximal leg muscles with marked asymmetry. These observations expand the clinical spectrum of LDM with the MYH7 mutation.
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Affiliation(s)
- Jin-Mo Park
- Department of Neurology, Ewha Womans University School of Medicine, Seoul, Republic of Korea
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12
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Tajsharghi H, Oldfors A. Myosinopathies: pathology and mechanisms. Acta Neuropathol 2013; 125:3-18. [PMID: 22918376 PMCID: PMC3535372 DOI: 10.1007/s00401-012-1024-2] [Citation(s) in RCA: 127] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2012] [Revised: 06/27/2012] [Accepted: 07/19/2012] [Indexed: 11/24/2022]
Abstract
The myosin heavy chain (MyHC) is the molecular motor of muscle and forms the backbone of the sarcomere thick filaments. Different MyHC isoforms are of importance for the physiological properties of different muscle fiber types. Hereditary myosin myopathies have emerged as an important group of diseases with variable clinical and morphological expression depending on the mutated isoform and type and location of the mutation. Dominant mutations in developmental MyHC isoform genes (MYH3 and MYH8) are associated with distal arthrogryposis syndromes. Dominant or recessive mutations affecting the type IIa MyHC (MYH2) are associated with early-onset myopathies with variable muscle weakness and ophthalmoplegia as a consistent finding. Myopathies with scapuloperoneal, distal or limb-girdle muscle weakness including entities, such as myosin storage myopathy and Laing distal myopathy are the result of usually dominant mutations in the gene for slow/β cardiac MyHC (MYH7). Protein aggregation is part of the features in some of these myopathies. In myosin storage myopathy protein aggregates are formed by accumulation of myosin beneath the sarcolemma and between myofibrils. In vitro studies on the effects of different mutations associated with myosin storage myopathy and Laing distal myopathy indicate altered biochemical and biophysical properties of the light meromyosin, which is essential for thick filament assembly. Protein aggregates in the form of tubulofilamentous inclusions in association with vacuolated muscle fibers are present at late stage of dominant myosin IIa myopathy and sometimes in Laing distal myopathy. These protein aggregates exhibit features indicating defective degradation of misfolded proteins. In addition to protein aggregation and muscle fiber degeneration some of the myosin mutations cause functional impairment of the molecular motor adding to the pathogenesis of myosinopathies.
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Affiliation(s)
- Homa Tajsharghi
- Department of Pathology, Institute of Biomedicine, University of Gothenburg, Sahlgrenska University Hospital, 413 45 Gothenburg, Sweden
| | - Anders Oldfors
- Department of Pathology, Institute of Biomedicine, University of Gothenburg, Sahlgrenska University Hospital, 413 45 Gothenburg, Sweden
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Buvoli M, Buvoli A, Leinwand LA. Effects of pathogenic proline mutations on myosin assembly. J Mol Biol 2011; 415:807-18. [PMID: 22155079 DOI: 10.1016/j.jmb.2011.11.042] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2011] [Revised: 11/04/2011] [Accepted: 11/23/2011] [Indexed: 12/27/2022]
Abstract
Laing distal myopathy (MPD1) is a genetically dominant myopathy characterized by early and selective weakness of the distal muscles. Mutations in the MYH7 gene encoding for the β-myosin heavy chain are the underlying genetic cause of MPD1. However, their pathogenic mechanisms are currently unknown. Here, we measure the biological effects of the R1500P and L1706P MPD1 mutations in different cellular systems. We show that, while the two mutations inhibit myosin self-assembly in non-muscle cells, they do not prevent incorporation of the mutant myosin into sarcomeres. Nevertheless, we find that the L1706P mutation affects proper antiparallel myosin association by accumulating in the bare zone of the sarcomere. Furthermore, bimolecular fluorescence complementation assay shows that the α-helix containing the R1500P mutation folds into homodimeric (mutant/mutant) and heterodimeric [mutant/wild type (WT)] myosin molecules that are competent for sarcomere incorporation. Both mutations also form aggregates consisting of cytoplasmic vacuoles surrounding paracrystalline arrays and amorphous rod-like inclusions that sequester WT myosin. Myosin aggregates were also detected in transgenic nematodes expressing the R1500P mutation. By showing that the two MPD1 mutations can have dominant effects on distinct components of the contractile apparatus, our data provide the first insights into the pathogenesis of the disease.
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Affiliation(s)
- Massimo Buvoli
- Department of Molecular, Cellular, and Developmental Biology and Biofrontiers Institute, University of Colorado, Boulder, CO 80309, USA
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14
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Abstract
Distal muscular dystrophies are a group of inherited primary muscle disorders showing progressive weakness and atrophy preferentially in the hands, forearm, lower legs, or feet. Extensive progress in understanding the molecular genetic background has changed the classification and extended the list of confirmed entities to almost 20 different disorders, making the differential diagnostic procedure both easier and more difficult. Distal phenotypes first have to be differentiated from neurogenic disorders. The axonal form of Charcot-Marie-Tooth disease with late-onset distal weakness and distal forms of chronic spinal muscular atrophy may mimic those of the distal dystrophies. Increasing numbers of reports suggest increasing awareness of distal phenotypes in muscular dystrophy. Some disorders regularly progress eventually to involve proximal muscle, whereas others, such as tibial muscular dystrophy titinopathy (Udd), Welander distal myopathy, and distal myosinopathy (Laing), remain distal throughout the patient's lifetime. Pathologically there is a gradual degeneration and loss of muscle fibers with replacement by fibrous and fatty connective tissue, similar to the proximal forms of muscular dystrophy, frequently, but not always with rimmed vacuolar degenerative change. Strikingly, many of the genes involved in distal dystrophies code for sarcomeric proteins. However, the genetic programs leading to preferential involvement of distal muscles have remained unknown.
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Affiliation(s)
- Bjarne Udd
- Department of Neurology, Tampere University and University Hospital, Tampere, Finland.
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15
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A novel MYH7 mutation occurring independently in French and Norwegian Laing distal myopathy families and de novo in one Finnish patient. J Neurol 2011; 258:1157-63. [DOI: 10.1007/s00415-011-5900-9] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2010] [Revised: 12/29/2010] [Accepted: 01/03/2011] [Indexed: 12/19/2022]
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16
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Cirak S, von Deimling F, Sachdev S, Errington WJ, Herrmann R, Bönnemann C, Brockmann K, Hinderlich S, Lindner TH, Steinbrecher A, Hoffmann K, Privé GG, Hannink M, Nürnberg P, Voit T. Kelch-like homologue 9 mutation is associated with an early onset autosomal dominant distal myopathy. ACTA ACUST UNITED AC 2010; 133:2123-35. [PMID: 20554658 PMCID: PMC2892937 DOI: 10.1093/brain/awq108] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/02/2022]
Abstract
Distal myopathies are a heterogeneous group of disorders characterized by progressive weakness and muscular atrophy, beginning in distal limb muscles and affecting proximal limb muscles at a later stage. We studied a large German kindred with 10 affected members. Weakness and atrophy of the anterior tibial muscles started between the ages of 8 and 16 years, followed by atrophy of intrinsic hand muscles. Progression was slow, and patients retained the ability to walk until the seventh decade. Serum creatinine kinase levels were increased in the range of 150–1400 U/l. Muscle biopsies showed myopathic changes, whereas immunohistochemistry showed normal expression of marker proteins for muscular dystrophies. Patients had reduced sensation with stocking-glove distribution in the distal limbs in later life. Nerve conduction studies revealed no evidence of neuropathy. Genome-wide linkage analysis in this family revealed a new locus for distal myopathy at 9p21.2-p22.3 (multipoint logarithm of the odds ratio = 4.21). By positional cloning we found a heterozygous mutation L95F in the Kelch-like homologue 9 gene, encoding a bric-a-brac Kelch protein. Molecular modelling indicated that the mutation may interfere with the interaction of the bric-a-brac domain with Cullin 3. Coimmunoprecipitation experiments confirmed that the mutation reduces association with Cullin 3 in the Kelch-like homologue 9-Cullin 3–E3 ubiquitin ligase complex, which is involved in ubiquitin-dependent protein degradation. We identified a unique form of early onset autosomal dominant distal myopathy which is associated with a Kelch-like homologue 9 mutation and interferes with normal skeletal muscle through a novel pathogenetic mechanism.
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Affiliation(s)
- Sebahattin Cirak
- Institute of Child Health, Dubowitz Neuromuscular Centre, 30 Guilford Street, London WC1N1EH, UK.
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17
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Oldfors A. Hereditary myosin myopathies. Neuromuscul Disord 2007; 17:355-67. [PMID: 17434305 DOI: 10.1016/j.nmd.2007.02.008] [Citation(s) in RCA: 96] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2007] [Revised: 02/03/2007] [Accepted: 02/03/2007] [Indexed: 12/11/2022]
Abstract
Hereditary myosin myopathies have emerged as a new group of muscle diseases with highly variable clinical features and onset during fetal development, childhood or adulthood. They are caused by mutations in skeletal muscle myosin heavy chain (MyHC) genes. Mutations have been reported in two of the three MyHC isoforms expressed in adult limb skeletal muscle: type I (slow/beta-cardiac MyHC; MYH7) and type IIa (MYH2). The majority of more than 200 dominant missense mutations in MYH7 are associated with hypertrophic/dilated cardiomyopathy without signs or symptoms of skeletal myopathy. Several mutations in two different parts of the slow/beta-cardiac MyHC rod region are associated with two distinct skeletal myopathies without cardiomyopathy: Laing early onset distal myopathy and myosin storage myopathy (MSM). However, early onset distal myopathy and MSM caused by MYH7 mutations may also occur together with cardiomyopathy. MSM affects proximal or scapuloperoneal muscles whereas Laing distal myopathy primarily affects the dorsiflexor muscles of the toes and ankles. MSM is morphologically characterized by subsarcolemmal accumulation of myosin in type 1 fibers, whereas Laing distal myopathy is associated with variable and unspecific muscle pathology, frequently with hypotrophic type 1 muscle fibers. A myopathy associated with a specific mutation in MYH2 is associated with congenital joint contractures and external ophthalmoplegia. The disease is mild in childhood but may be progressive in adulthood, with proximal muscle weakness affecting ambulation. Mutations in embryonic MyHC (MYH3) and perinatal MyHC (MYH8), which are myosin isoforms expressed during muscle development, are associated with distal arthrogryposis syndromes with no or minor muscle weakness. Clinical findings, muscle morphology and molecular genetics in hereditary myosin myopathies are summarized in this review.
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Affiliation(s)
- Anders Oldfors
- Department of Pathology, Sahlgrenska University Hospital, S-413 45 Göteborg, Sweden.
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Pegoraro E, Gavassini BF, Borsato C, Melacini P, Vianello A, Stramare R, Cenacchi G, Angelini C. MYH7 gene mutation in myosin storage myopathy and scapulo-peroneal myopathy. Neuromuscul Disord 2007; 17:321-9. [PMID: 17336526 DOI: 10.1016/j.nmd.2007.01.010] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2006] [Revised: 01/08/2007] [Accepted: 01/17/2007] [Indexed: 11/26/2022]
Abstract
In order to characterize, at the clinical, molecular and imaging level, myopathies due to MYH7 gene mutations, MYH7 gene analysis was conducted by RT-PCR/SSCP/sequencing in two patients diagnosed with myosin storage myopathy and 17 patients diagnosed with scapulo-peroneal myopathy of unknown etiology. MYH7 gene studies revealed the 5533C>T mutation (Arg1845Trp) in both myosin storage myopathy and in 2 of the 17 scapulo-peroneal patients studied. 5533C>T segregation analysis in the mutation carrier families identified 11 additional patients. The clinical spectrum in our cohort of patients included asymptomatic hyperCKemia, scapulo-peroneal myopathy and proximal and distal myopathy with muscle hypertrophy. Muscle MRI identified a unique pattern in the posterior compartment of the thigh, characterized by early involvement of the biceps femoris and semimembranosus, with relative sparing of the semitendinosus. Muscle biopsy revealed hyaline bodies in only half of biopsied patients (2/4). In conclusion, phenotypic and histopathological variability may underlie MYH7 gene mutation and the absence of hyaline bodies in muscle biopsies does not rule out MYH7 gene mutations.
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Affiliation(s)
- Elena Pegoraro
- Department of Neurosciences, University of Padova, Italy.
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20
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Udd B. Molecular biology of distal muscular dystrophies--sarcomeric proteins on top. Biochim Biophys Acta Mol Basis Dis 2006; 1772:145-58. [PMID: 17029922 DOI: 10.1016/j.bbadis.2006.08.005] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2006] [Revised: 08/07/2006] [Accepted: 08/15/2006] [Indexed: 11/18/2022]
Abstract
During the last 10 years several muscular dystrophies within the group of distal myopathies have been clarified as to the molecular genetic cause of the disease. Currently, the next steps are carried out to identify the molecular pathogenesis downstream of the gene defects. Some early ideas on what is going on in the muscle cells based on the defect proteins are emerging. However, in no single distal muscular dystrophy these efforts have yet reached the point where direct trials for therapy would have been launched, and in many distal dystrophies the causative gene is still lacking. When comparing the gene defects in the distal dystrophies with the more common proximal muscular dystrophies such as dystrophinopathies or limb-girdle muscular dystrophies, there is a striking difference: the genes for distal dystrophies encode sarcomere proteins whereas the genes for proximal dystrophies more often encode sarcolemmal proteins.
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Affiliation(s)
- Bjarne Udd
- Department of Neurology, Tampere University Hospital and Vasa Central Hospital, University of Tampere Medical Scool, Finland.
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21
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Abstract
PURPOSE OF REVIEW The distal myopathies are a heterogeneous group of disorders that pose a challenge to both the clinician and geneticist. This article summarizes the findings of recent clinical, genetic and molecular studies and the current diagnostic approach to this group of patients. RECENT FINDINGS Publications over the past 5 years describe a number of new clinical phenotypes and genetic loci and further emphasize the overlap in clinical phenotype between a number of these disorders and between the distal and limb girdle myopathies and hereditary inclusion body myopathies. Recent studies have led to the identification of the genes and mutations responsible for early onset (Laing) myopathy and tibial (Udd) myopathy, and for distal myopathy with rimmed vacuoles (Nonaka), which has been shown to be allelic with quadriceps sparing hereditary inclusion body myopathy (IBM2), and have elucidated the underlying pathogenetic mechanisms in these conditions. New diagnostic approaches using magnetic resonance imaging, and a blood-based assay for dysferlin deficiency, have also been reported. SUMMARY These findings have important implications for future genetic linkage and gene expression studies and for the diagnostic approach to patients with a distal myopathy phenotype. They also hold promise for the eventual development of therapies for this group of disorders.
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Affiliation(s)
- Frank L Mastaglia
- Centre for Neuromuscular and Neurological Disorders, University of Western Australia, Perth, Western Australia, Australia.
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22
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Lamont PJ, Udd B, Mastaglia FL, de Visser M, Hedera P, Voit T, Bridges LR, Fabian V, Rozemuller A, Laing NG. Laing early onset distal myopathy: slow myosin defect with variable abnormalities on muscle biopsy. J Neurol Neurosurg Psychiatry 2006; 77:208-15. [PMID: 16103042 PMCID: PMC2077563 DOI: 10.1136/jnnp.2005.073825] [Citation(s) in RCA: 75] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
BACKGROUND Laing early onset distal myopathy (MPD1) is an autosomal dominant myopathy caused by mutations within the slow skeletal muscle fibre myosin heavy chain gene, MYH7. It is allelic with myosin storage myopathy, with the commonest form of familial hypertrophic cardiomyopathy, and with one form of dilated cardiomyopathy. However, the clinical picture of MPD1 is distinct from these three conditions. OBJECTIVE To collate and discuss the histological features reported in the muscle biopsies of MPD1 patients and to outline the clinical features. RESULTS The phenotype of MPD1 was consistent, with initial weakness of great toe/ankle dorsiflexion, and later development of weakness of finger extension and neck flexion. Age of onset was the only variable, being from birth up to the 20 s, but progression was always very slow. The pathological features were variable. In this retrospective series, there were no pathognomonic diagnostic features, although atrophic type I fibres were found in half the families. Rimmed vacuoles are consistently seen in all other distal myopathies with the exception of Myoshi distal myopathy. However, they were found in a minority of patients with MPD1, and were not prominent when present. Immunohistochemical staining for slow and fast myosin showed co-expression of slow and fast myosin in some type I fibres, possibly indicating a switch to type II status. This may be a useful aid to diagnosis. CONCLUSIONS The pathological findings in MPD1 are variable and appear to be affected by factors such as the specific muscle biopsied, the age of the patient at biopsy, and the duration of disease manifestations.
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Affiliation(s)
- P J Lamont
- Neurogenetic Unit, Department of Neurology, Royal Perth Hospital, Box X2213 GPO, Perth, Western Australia 6847.
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Laing NG, Nowak KJ. When contractile proteins go bad: the sarcomere and skeletal muscle disease. Bioessays 2005; 27:809-22. [PMID: 16015601 DOI: 10.1002/bies.20269] [Citation(s) in RCA: 72] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
The sarcomere is the functional unit of striated muscle contraction. Mutations in sarcomeric proteins are now known to cause around 20 different skeletal muscle diseases. The diseases vary in severity from paralysis at birth, to mild conditions compatible with normal life span. The identification of the disease genes allows more accurate diagnosis, including prenatal diagnosis. Although many disease genes have been identified, the pathophysiology of the gene defects remains remarkably obscure, considering that many of the proteins have been researched for decades. The short-term goals are to determine the remaining disease genes and to decipher pathogenesis. The long-term goal is to develop effective therapies-a daunting task when humans are up to 40% muscle and the mutated proteins are fundamental to muscle contraction. The affected patients and families hope for help sooner rather than later. The onus is on all scientists researching sarcomeric proteins to help develop treatments.
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Affiliation(s)
- Nigel G Laing
- Centre for Medical Research, University of Western Australia, West Australian Institute for Medical Research, Nedlands, Western Australia, Australia.
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Meredith C, Herrmann R, Parry C, Liyanage K, Dye DE, Durling HJ, Duff RM, Beckman K, de Visser M, van der Graaff MM, Hedera P, Fink JK, Petty EM, Lamont P, Fabian V, Bridges L, Voit T, Mastaglia FL, Laing NG. Mutations in the slow skeletal muscle fiber myosin heavy chain gene (MYH7) cause laing early-onset distal myopathy (MPD1). Am J Hum Genet 2004; 75:703-8. [PMID: 15322983 PMCID: PMC1182058 DOI: 10.1086/424760] [Citation(s) in RCA: 168] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2004] [Accepted: 07/23/2004] [Indexed: 11/03/2022] Open
Abstract
We previously linked Laing-type early-onset autosomal dominant distal myopathy (MPD1) to a 22-cM region of chromosome 14. One candidate gene in the region, MYH7, which is mutated in cardiomyopathy and myosin storage myopathy, codes for the myosin heavy chain of type I skeletal muscle fibers and cardiac ventricles. We have identified five novel heterozygous mutations--Arg1500Pro, Lys1617del, Ala1663Pro, Leu1706Pro, and Lys1729del in exons 32, 34, 35, and 36 of MYH7--in six families with early-onset distal myopathy. All five mutations are predicted, by in silico analysis, to locally disrupt the ability of the myosin tail to form the coiled coil, which is its normal structure. These findings demonstrate that heterozygous mutations toward the 3' end of MYH7 cause Laing-type early-onset distal myopathy. MYH7 is the fourth distal-myopathy gene to have been identified.
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Affiliation(s)
- Christopher Meredith
- Centre for Human Genetics, Edith Cowan University, and Departments of Neurology and Anatomical Pathology, Royal Perth Hospital, Perth, Australia; Department of Pediatrics and Pediatric Neurology, University Hospital Essen, Essen, Germany; Centre for Neuromuscular and Neurological Disorders, Australian Neuromuscular Research Institute, and Centre for Medical Research, West Australian Institute for Medical Research, University of Western Australia, Nedlands; Academic Medical Center, Department of Neurology, University of Amsterdam, Amsterdam; and Departments of Neurology and Human Genetics and Internal Medicine, University of Michigan, and Geriatric Research Education and Clinical Center, Ann Arbor Veterans Affairs Medical Center, Ann Arbor
| | - Ralf Herrmann
- Centre for Human Genetics, Edith Cowan University, and Departments of Neurology and Anatomical Pathology, Royal Perth Hospital, Perth, Australia; Department of Pediatrics and Pediatric Neurology, University Hospital Essen, Essen, Germany; Centre for Neuromuscular and Neurological Disorders, Australian Neuromuscular Research Institute, and Centre for Medical Research, West Australian Institute for Medical Research, University of Western Australia, Nedlands; Academic Medical Center, Department of Neurology, University of Amsterdam, Amsterdam; and Departments of Neurology and Human Genetics and Internal Medicine, University of Michigan, and Geriatric Research Education and Clinical Center, Ann Arbor Veterans Affairs Medical Center, Ann Arbor
| | - Cheryl Parry
- Centre for Human Genetics, Edith Cowan University, and Departments of Neurology and Anatomical Pathology, Royal Perth Hospital, Perth, Australia; Department of Pediatrics and Pediatric Neurology, University Hospital Essen, Essen, Germany; Centre for Neuromuscular and Neurological Disorders, Australian Neuromuscular Research Institute, and Centre for Medical Research, West Australian Institute for Medical Research, University of Western Australia, Nedlands; Academic Medical Center, Department of Neurology, University of Amsterdam, Amsterdam; and Departments of Neurology and Human Genetics and Internal Medicine, University of Michigan, and Geriatric Research Education and Clinical Center, Ann Arbor Veterans Affairs Medical Center, Ann Arbor
| | - Khema Liyanage
- Centre for Human Genetics, Edith Cowan University, and Departments of Neurology and Anatomical Pathology, Royal Perth Hospital, Perth, Australia; Department of Pediatrics and Pediatric Neurology, University Hospital Essen, Essen, Germany; Centre for Neuromuscular and Neurological Disorders, Australian Neuromuscular Research Institute, and Centre for Medical Research, West Australian Institute for Medical Research, University of Western Australia, Nedlands; Academic Medical Center, Department of Neurology, University of Amsterdam, Amsterdam; and Departments of Neurology and Human Genetics and Internal Medicine, University of Michigan, and Geriatric Research Education and Clinical Center, Ann Arbor Veterans Affairs Medical Center, Ann Arbor
| | - Danielle E. Dye
- Centre for Human Genetics, Edith Cowan University, and Departments of Neurology and Anatomical Pathology, Royal Perth Hospital, Perth, Australia; Department of Pediatrics and Pediatric Neurology, University Hospital Essen, Essen, Germany; Centre for Neuromuscular and Neurological Disorders, Australian Neuromuscular Research Institute, and Centre for Medical Research, West Australian Institute for Medical Research, University of Western Australia, Nedlands; Academic Medical Center, Department of Neurology, University of Amsterdam, Amsterdam; and Departments of Neurology and Human Genetics and Internal Medicine, University of Michigan, and Geriatric Research Education and Clinical Center, Ann Arbor Veterans Affairs Medical Center, Ann Arbor
| | - Hayley J. Durling
- Centre for Human Genetics, Edith Cowan University, and Departments of Neurology and Anatomical Pathology, Royal Perth Hospital, Perth, Australia; Department of Pediatrics and Pediatric Neurology, University Hospital Essen, Essen, Germany; Centre for Neuromuscular and Neurological Disorders, Australian Neuromuscular Research Institute, and Centre for Medical Research, West Australian Institute for Medical Research, University of Western Australia, Nedlands; Academic Medical Center, Department of Neurology, University of Amsterdam, Amsterdam; and Departments of Neurology and Human Genetics and Internal Medicine, University of Michigan, and Geriatric Research Education and Clinical Center, Ann Arbor Veterans Affairs Medical Center, Ann Arbor
| | - Rachael M. Duff
- Centre for Human Genetics, Edith Cowan University, and Departments of Neurology and Anatomical Pathology, Royal Perth Hospital, Perth, Australia; Department of Pediatrics and Pediatric Neurology, University Hospital Essen, Essen, Germany; Centre for Neuromuscular and Neurological Disorders, Australian Neuromuscular Research Institute, and Centre for Medical Research, West Australian Institute for Medical Research, University of Western Australia, Nedlands; Academic Medical Center, Department of Neurology, University of Amsterdam, Amsterdam; and Departments of Neurology and Human Genetics and Internal Medicine, University of Michigan, and Geriatric Research Education and Clinical Center, Ann Arbor Veterans Affairs Medical Center, Ann Arbor
| | - Kaye Beckman
- Centre for Human Genetics, Edith Cowan University, and Departments of Neurology and Anatomical Pathology, Royal Perth Hospital, Perth, Australia; Department of Pediatrics and Pediatric Neurology, University Hospital Essen, Essen, Germany; Centre for Neuromuscular and Neurological Disorders, Australian Neuromuscular Research Institute, and Centre for Medical Research, West Australian Institute for Medical Research, University of Western Australia, Nedlands; Academic Medical Center, Department of Neurology, University of Amsterdam, Amsterdam; and Departments of Neurology and Human Genetics and Internal Medicine, University of Michigan, and Geriatric Research Education and Clinical Center, Ann Arbor Veterans Affairs Medical Center, Ann Arbor
| | - Marianne de Visser
- Centre for Human Genetics, Edith Cowan University, and Departments of Neurology and Anatomical Pathology, Royal Perth Hospital, Perth, Australia; Department of Pediatrics and Pediatric Neurology, University Hospital Essen, Essen, Germany; Centre for Neuromuscular and Neurological Disorders, Australian Neuromuscular Research Institute, and Centre for Medical Research, West Australian Institute for Medical Research, University of Western Australia, Nedlands; Academic Medical Center, Department of Neurology, University of Amsterdam, Amsterdam; and Departments of Neurology and Human Genetics and Internal Medicine, University of Michigan, and Geriatric Research Education and Clinical Center, Ann Arbor Veterans Affairs Medical Center, Ann Arbor
| | - Maaike M. van der Graaff
- Centre for Human Genetics, Edith Cowan University, and Departments of Neurology and Anatomical Pathology, Royal Perth Hospital, Perth, Australia; Department of Pediatrics and Pediatric Neurology, University Hospital Essen, Essen, Germany; Centre for Neuromuscular and Neurological Disorders, Australian Neuromuscular Research Institute, and Centre for Medical Research, West Australian Institute for Medical Research, University of Western Australia, Nedlands; Academic Medical Center, Department of Neurology, University of Amsterdam, Amsterdam; and Departments of Neurology and Human Genetics and Internal Medicine, University of Michigan, and Geriatric Research Education and Clinical Center, Ann Arbor Veterans Affairs Medical Center, Ann Arbor
| | - Peter Hedera
- Centre for Human Genetics, Edith Cowan University, and Departments of Neurology and Anatomical Pathology, Royal Perth Hospital, Perth, Australia; Department of Pediatrics and Pediatric Neurology, University Hospital Essen, Essen, Germany; Centre for Neuromuscular and Neurological Disorders, Australian Neuromuscular Research Institute, and Centre for Medical Research, West Australian Institute for Medical Research, University of Western Australia, Nedlands; Academic Medical Center, Department of Neurology, University of Amsterdam, Amsterdam; and Departments of Neurology and Human Genetics and Internal Medicine, University of Michigan, and Geriatric Research Education and Clinical Center, Ann Arbor Veterans Affairs Medical Center, Ann Arbor
| | - John K. Fink
- Centre for Human Genetics, Edith Cowan University, and Departments of Neurology and Anatomical Pathology, Royal Perth Hospital, Perth, Australia; Department of Pediatrics and Pediatric Neurology, University Hospital Essen, Essen, Germany; Centre for Neuromuscular and Neurological Disorders, Australian Neuromuscular Research Institute, and Centre for Medical Research, West Australian Institute for Medical Research, University of Western Australia, Nedlands; Academic Medical Center, Department of Neurology, University of Amsterdam, Amsterdam; and Departments of Neurology and Human Genetics and Internal Medicine, University of Michigan, and Geriatric Research Education and Clinical Center, Ann Arbor Veterans Affairs Medical Center, Ann Arbor
| | - Elizabeth M. Petty
- Centre for Human Genetics, Edith Cowan University, and Departments of Neurology and Anatomical Pathology, Royal Perth Hospital, Perth, Australia; Department of Pediatrics and Pediatric Neurology, University Hospital Essen, Essen, Germany; Centre for Neuromuscular and Neurological Disorders, Australian Neuromuscular Research Institute, and Centre for Medical Research, West Australian Institute for Medical Research, University of Western Australia, Nedlands; Academic Medical Center, Department of Neurology, University of Amsterdam, Amsterdam; and Departments of Neurology and Human Genetics and Internal Medicine, University of Michigan, and Geriatric Research Education and Clinical Center, Ann Arbor Veterans Affairs Medical Center, Ann Arbor
| | - Phillipa Lamont
- Centre for Human Genetics, Edith Cowan University, and Departments of Neurology and Anatomical Pathology, Royal Perth Hospital, Perth, Australia; Department of Pediatrics and Pediatric Neurology, University Hospital Essen, Essen, Germany; Centre for Neuromuscular and Neurological Disorders, Australian Neuromuscular Research Institute, and Centre for Medical Research, West Australian Institute for Medical Research, University of Western Australia, Nedlands; Academic Medical Center, Department of Neurology, University of Amsterdam, Amsterdam; and Departments of Neurology and Human Genetics and Internal Medicine, University of Michigan, and Geriatric Research Education and Clinical Center, Ann Arbor Veterans Affairs Medical Center, Ann Arbor
| | - Vicki Fabian
- Centre for Human Genetics, Edith Cowan University, and Departments of Neurology and Anatomical Pathology, Royal Perth Hospital, Perth, Australia; Department of Pediatrics and Pediatric Neurology, University Hospital Essen, Essen, Germany; Centre for Neuromuscular and Neurological Disorders, Australian Neuromuscular Research Institute, and Centre for Medical Research, West Australian Institute for Medical Research, University of Western Australia, Nedlands; Academic Medical Center, Department of Neurology, University of Amsterdam, Amsterdam; and Departments of Neurology and Human Genetics and Internal Medicine, University of Michigan, and Geriatric Research Education and Clinical Center, Ann Arbor Veterans Affairs Medical Center, Ann Arbor
| | - Leslie Bridges
- Centre for Human Genetics, Edith Cowan University, and Departments of Neurology and Anatomical Pathology, Royal Perth Hospital, Perth, Australia; Department of Pediatrics and Pediatric Neurology, University Hospital Essen, Essen, Germany; Centre for Neuromuscular and Neurological Disorders, Australian Neuromuscular Research Institute, and Centre for Medical Research, West Australian Institute for Medical Research, University of Western Australia, Nedlands; Academic Medical Center, Department of Neurology, University of Amsterdam, Amsterdam; and Departments of Neurology and Human Genetics and Internal Medicine, University of Michigan, and Geriatric Research Education and Clinical Center, Ann Arbor Veterans Affairs Medical Center, Ann Arbor
| | - Thomas Voit
- Centre for Human Genetics, Edith Cowan University, and Departments of Neurology and Anatomical Pathology, Royal Perth Hospital, Perth, Australia; Department of Pediatrics and Pediatric Neurology, University Hospital Essen, Essen, Germany; Centre for Neuromuscular and Neurological Disorders, Australian Neuromuscular Research Institute, and Centre for Medical Research, West Australian Institute for Medical Research, University of Western Australia, Nedlands; Academic Medical Center, Department of Neurology, University of Amsterdam, Amsterdam; and Departments of Neurology and Human Genetics and Internal Medicine, University of Michigan, and Geriatric Research Education and Clinical Center, Ann Arbor Veterans Affairs Medical Center, Ann Arbor
| | - Frank L. Mastaglia
- Centre for Human Genetics, Edith Cowan University, and Departments of Neurology and Anatomical Pathology, Royal Perth Hospital, Perth, Australia; Department of Pediatrics and Pediatric Neurology, University Hospital Essen, Essen, Germany; Centre for Neuromuscular and Neurological Disorders, Australian Neuromuscular Research Institute, and Centre for Medical Research, West Australian Institute for Medical Research, University of Western Australia, Nedlands; Academic Medical Center, Department of Neurology, University of Amsterdam, Amsterdam; and Departments of Neurology and Human Genetics and Internal Medicine, University of Michigan, and Geriatric Research Education and Clinical Center, Ann Arbor Veterans Affairs Medical Center, Ann Arbor
| | - Nigel G. Laing
- Centre for Human Genetics, Edith Cowan University, and Departments of Neurology and Anatomical Pathology, Royal Perth Hospital, Perth, Australia; Department of Pediatrics and Pediatric Neurology, University Hospital Essen, Essen, Germany; Centre for Neuromuscular and Neurological Disorders, Australian Neuromuscular Research Institute, and Centre for Medical Research, West Australian Institute for Medical Research, University of Western Australia, Nedlands; Academic Medical Center, Department of Neurology, University of Amsterdam, Amsterdam; and Departments of Neurology and Human Genetics and Internal Medicine, University of Michigan, and Geriatric Research Education and Clinical Center, Ann Arbor Veterans Affairs Medical Center, Ann Arbor
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25
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Abstract
Distal myopathies are a heterogeneous group of genetic disorders characterized clinically by progressive muscular weakness and atrophy beginning in the hands or feet, and pathologically by myopathic changes in skeletal muscles. Five distinct distal myopathies are identified, among them four have been recently defined by their gene and causative mutations. They are classified according to age at onset, mode of inheritance, and muscle groups initially involved into the following: Laing myopathy (infancy onset, autosomal dominant inheritance, onset in anterior compartment of legs) caused by mutations in a myosin gene (MYH7) on chromosome 14q; Nonaka myopathy (early adult onset, autosomal recessive inheritance, onset in anterior compartment of legs), identical to quadriceps-sparing familial inclusion myopathy, caused by mutations in the GNE gene on chromosome 9p-q; Miyoshi myopathy (early adult onset, autosomal recessive inheritance, onset in posterior compartment of legs) caused by mutations in the dysferlin gene on chromosome 2p; Welander myopathy (late adult onset, autosomal dominant inheritance, onset in hands) linked to chromosome 2p; Udd/Markesbery-Griggs myopathy (late adult onset, autosomal dominant inheritance, onset in anterior compartment of legs) caused by mutations in the titin gene on chromosome 2q. Except for Miyoshi myopathy, which has a striking elevated serum creatine kinase level and the typical findings of muscular dystrophy, most of the distal myopathies have normal or midly elevated creatine kinase levels and share the common pathologic feature of rimmed vacuoles.
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Affiliation(s)
- I Pénisson-Besnier
- Département de Neurologie, Hôpital Larrey, Centre Hospitalier Universitaire d'Angers, 4 rue Larrey, 49033 Angers cedex 01.
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