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Cheung A, Audhya IF, Szabo SM, Friesen M, Weihl CC, Gooch KL. Patterns of Clinical Progression Among Patients With Autosomal Recessive Limb-Girdle Muscular Dystrophy: A Systematic Review. J Clin Neuromuscul Dis 2023; 25:65-80. [PMID: 37962193 DOI: 10.1097/cnd.0000000000000461] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2023]
Abstract
OBJECTIVES As the clinical course of autosomal recessive limb-girdle muscular dystrophy (LGMDR) is highly variable, this study characterized the frequency of loss of ambulation (LOA) among patients by subtype (LGMDR1, LGMDR2, LGMDR3-6, LGMDR9, LGMDR12) and progression to cardiac and respiratory involvement among those with and without LOA. METHODS Systematic literature review. RESULTS From 2929 abstracts screened, 418 patients were identified with ambulatory status data (LOA: 265 [63.4%]). Cardiac and/or respiratory function was reported for 142 patients (34.0%; all with LOA). Among these, respiratory involvement was most frequent in LGMDR3-6 (74.1%; mean [SD] age 23.9 [11.0] years) and cardiac in LGMDR9 (73.3%; mean [SD] age 23.7 [17.7] years). Involvement was less common in patients without LOA except in LGMDR9 (71.4% respiratory and 52.4% cardiac). CONCLUSIONS This study described the co-occurrence of LOA, cardiac, and respiratory involvement in LGMDR and provides greater understanding of the clinical progression of LGMDR.
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Affiliation(s)
| | | | | | | | - Conrad C Weihl
- Department of Neurology, Hope Center for Neurological Diseases, Washington University School of Medicine, St. Louis, MO
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Savarese M, Jokela M, Udd B. Distal myopathy. HANDBOOK OF CLINICAL NEUROLOGY 2023; 195:497-519. [PMID: 37562883 DOI: 10.1016/b978-0-323-98818-6.00002-9] [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
Distal myopathies are a group of genetic, primary muscle diseases. Patients develop progressive weakness and atrophy of the muscles of forearm, hands, lower leg, or feet. Currently, over 20 different forms, presenting a variable age of onset, clinical presentation, disease progression, muscle involvement, and histological findings, are known. Some of them are dominant and some recessive. Different variants in the same gene are often associated with either dominant or recessive forms, although there is a lack of a comprehensive understanding of the genotype-phenotype correlations. This chapter provides a description of the clinicopathologic and genetic aspects of distal myopathies emphasizing known etiologic and pathophysiologic mechanisms.
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Affiliation(s)
- Marco Savarese
- Folkhälsan Research Center, Helsinki, Finland; Department of Medical Genetics, Medicum, University of Helsinki, Helsinki, Finland
| | - Manu Jokela
- Neuromuscular Research Center, Department of Neurology, Tampere University and University Hospital, Tampere, Finland; Division of Clinical Neurosciences, Department of Neurology, Turku University Hospital, Turku, Finland
| | - Bjarne Udd
- Folkhälsan Research Center, Helsinki, Finland; Department of Medical Genetics, Medicum, University of Helsinki, Helsinki, Finland; Neuromuscular Research Center, Department of Neurology, Tampere University and University Hospital, Tampere, Finland; Department of Neurology, Vaasa Central Hospital, Vaasa, Finland.
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Audhya IF, Cheung A, Szabo SM, Flint E, Weihl CC, Gooch KL. Progression to Loss of Ambulation Among Patients with Autosomal Recessive Limb-girdle Muscular Dystrophy: A Systematic Review. J Neuromuscul Dis 2022; 9:477-492. [PMID: 35527561 PMCID: PMC9398075 DOI: 10.3233/jnd-210771] [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] [Indexed: 12/02/2022]
Abstract
Background The impact of age at autosomal recessive limb girdle muscular dystrophy (LGMDR) onset on progression to loss of ambulation (LOA) has not been well established, particularly by subtype. Objectives: To describe the characteristics of patients with adult-, late childhood-, and early childhood-onset LGMDR by subtype and characterize the frequency and timing of LOA. Methods: A systematic review was conducted in MEDLINE, Embase and the Cochrane library. Frequency and timing of LOA in patients with LGMDR1, LGMDR2/Miyoshi myopathy (MM), LGMDR3-6, LGMDR9, and LGMDR12 were synthesized from published data. Results: In 195 studies, 695 (43.4%) patients had adult-, 532 (33.2%) had late childhood-, and 376 (23.5%) had early childhood-onset of disease across subtypes among those with a reported age at onset (n = 1,603); distribution of age at onset varied between subtypes. Among patients with LOA (n = 228), adult-onset disease was uncommon in LGMDR3-6 (14%) and frequent in LGMDR2/MM (42%); LGMDR3-6 cases with LOA primarily had early childhood-onset (74%). Mean (standard deviation [SD]) time to LOA varied between subtypes and was shortest for patients with early childhood-onset LGMDR9 (12.0 [4.9] years, n = 19) and LGMDR3-6 (12.3 [10.7], n = 56) and longest for those with late childhood-onset LGMDR2/MM (21.4 [11.5], n = 36). Conclusions: This review illustrated that patients with early childhood-onset disease tend to have faster progression to LOA than those with late childhood- or adult-onset disease, particularly in LGMDR9. These findings provide a greater understanding of progression to LOA by LGMDR subtype, which may help inform clinical trial design and provide a basis for natural history studies.
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Affiliation(s)
| | | | | | - Emma Flint
- Broadstreet HEOR, Vancouver, BC, V6A 1A4 Canada
| | - Conrad C Weihl
- Washington University School of Medicine, St.Louis, MO, USA
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Advanced Gene-Targeting Therapies for Motor Neuron Diseases and Muscular Dystrophies. Int J Mol Sci 2022; 23:ijms23094824. [PMID: 35563214 PMCID: PMC9101723 DOI: 10.3390/ijms23094824] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2022] [Revised: 04/22/2022] [Accepted: 04/25/2022] [Indexed: 12/19/2022] Open
Abstract
Gene therapy is a revolutionary, cutting-edge approach to permanently ameliorate or amend many neuromuscular diseases by targeting their genetic origins. Motor neuron diseases and muscular dystrophies, whose genetic causes are well known, are the frontiers of this research revolution. Several genetic treatments, with diverse mechanisms of action and delivery methods, have been approved during the past decade and have demonstrated remarkable results. However, despite the high number of genetic treatments studied preclinically, those that have been advanced to clinical trials are significantly fewer. The most clinically advanced treatments include adeno-associated virus gene replacement therapy, antisense oligonucleotides, and RNA interference. This review provides a comprehensive overview of the advanced gene therapies for motor neuron diseases (i.e., amyotrophic lateral sclerosis and spinal muscular atrophy) and muscular dystrophies (i.e., Duchenne muscular dystrophy, limb-girdle muscular dystrophy, and myotonic dystrophy) tested in clinical trials. Emphasis has been placed on those methods that are a few steps away from their authoritative approval.
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Pozsgai E, Griffin D, Potter R, Sahenk Z, Lehman K, Rodino-Klapac LR, Mendell JR. Unmet needs and evolving treatment for limb girdle muscular dystrophies. Neurodegener Dis Manag 2021; 11:411-429. [PMID: 34472379 DOI: 10.2217/nmt-2020-0066] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Limb-girdle muscular dystrophies (LGMDs) represent a major group of muscle disorders. Treatment is sorely needed and currently expanding based on safety and efficacy adopting principles of single-dosing gene therapy for monogenic autosomal recessive disorders. Gene therapy has made in-roads for LGMD and this review describes progress that has been achieved for these conditions. This review first provides a background on the definition and classification of LGMDs. The major effort focuses on progress in LGMD gene therapy, from experimental studies to clinical trials. The disorders discussed include the LGMDs where the most work has been done including calpainopathies (LGMD2A/R1), dysferlinopathies (LGMD2B/R2) and sarcoglycanopathies (LGMD2C/R5, LGMD2D/R3, LGMD2E/R4). Early success in clinical trials provides a template to move the field forward and potentially apply emerging technology like CRISPR/Cas9 that may enhance the scope and efficacy of gene therapy applied to patient care.
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Affiliation(s)
- Eric Pozsgai
- Sarepta Therapeutics, Inc., Cambridge, MA 02142, USA
| | | | | | - Zarife Sahenk
- Center for Gene Therapy, The Research Institute at Nationwide Children's Hospital, Columbus, OH 43205, USA.,Department of Pediatrics & Neurology, The Ohio State University, Columbus, OH 43210, USA
| | - Kelly Lehman
- Center for Gene Therapy, The Research Institute at Nationwide Children's Hospital, Columbus, OH 43205, USA
| | | | - Jerry R Mendell
- Center for Gene Therapy, The Research Institute at Nationwide Children's Hospital, Columbus, OH 43205, USA.,Department of Pediatrics & Neurology, The Ohio State University, Columbus, OH 43210, USA
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Ganchinho Lucas S, Vieira Santos I, Pencas Alfaiate FJ, Lino I. A new dysferlin gene mutation in a Portuguese family with Miyoshi myopathy. BMJ Case Rep 2021; 14:14/7/e242341. [PMID: 34281941 DOI: 10.1136/bcr-2021-242341] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
Abstract
Dysferlinopathies are autosomal recessive muscular dystrophies caused by mutations in the dysferlin gene (DYSF). A 33-year-old man was born to a non-consanguineous couple. At the age of 25 he stared to feel weakness of the distal lower limbs and also experienced episodes of rhabdomyolysis. Electromyography showed a myopathic pattern, and muscle biopsy revealed dystrophic changes with absence of dysferlin. Genetic analysis was positive for a mutation in the c3367_3368del DYSF gene (p.Lys1123GLUFS*2). After 8 years of disease evolution the symptomatology worsened. This is the first report of this mutation of the DYSF gene identified in a non-consanguineous Portuguese family, studied over 8 years. We believe the mutation is responsible for the Miyoshi myopathy. Disease progression cannot be predicted in either the patient or carrier family because there are no similar cases previously described in the literature.
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Affiliation(s)
| | | | | | - Ireneia Lino
- Unidade de Hospitalização Domiciliária Polivalente, Hospital do Espírito Santo EPE, Évora, Portugal
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Jalali-Sefid-Dashti M, Nel M, Heckmann JM, Gamieldien J. Exome sequencing identifies novel dysferlin mutation in a family with pauci-symptomatic heterozygous carriers. BMC MEDICAL GENETICS 2018; 19:95. [PMID: 29879922 PMCID: PMC5992709 DOI: 10.1186/s12881-018-0613-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/24/2017] [Accepted: 05/23/2018] [Indexed: 12/20/2022]
Abstract
BACKGROUND We investigated a South African family of admixed ancestry in which the first generation (G1) developed insidious progressive distal to proximal weakness in their twenties, while their offspring (G2) experienced severe unexpected symptoms of myalgia and cramps since adolescence. Our aim was to identify deleterious mutations that segregate with the affected individuals in this family. METHODS Exome sequencing was performed on five cases, which included three affected G1 siblings and two pauci-symptomatic G2 offspring. As controls we included an unaffected G1 sibling and a spouse of one of the G1 affected individuals. Homozygous or potentially compound heterozygous variants that were predicted to be functional and segregated with the affected G1 siblings, were further evaluated. Additionally, we considered variants in all genes segregating exclusively with the affected (G1) and pauci-symptomatic (G2) individuals to address the possibility of a pseudo-autosomal dominant inheritance pattern in this family. RESULTS All affected G1 individuals were homozygous for a novel truncating p.Tyr1433Ter DYSF (dysferlin) mutation, with their asymptomatic sibling and both pauci-symptomatic G2 offspring carrying only a single mutant allele. Sanger sequencing confirmed segregation of the variant. No additional potentially contributing variant was found in the DYSF or any other relevant gene in the pauci-symptomatic carriers. CONCLUSION Our finding of a truncating dysferlin mutation confirmed dysferlinopathy in this family and we propose that the single mutant allele is the primary contributor to the neuromuscular symptoms seen in the second-generation pauci-symptomatic carriers.
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Affiliation(s)
- Mahjoubeh Jalali-Sefid-Dashti
- South African Medical Research Council Bioinformatics Unit, South African National Bioinformatics Institute, University of the Western Cape, Bellville, 7535, South Africa
| | - Melissa Nel
- Division of Neurology, Department of Medicine, University of Cape Town, Observatory, 7925, South Africa
| | - Jeannine M Heckmann
- E8-74, Neurology, New Groote Schuur Hospital Observatory, Cape Town, 7925, South Africa
| | - Junaid Gamieldien
- South African National Bioinformatics Institute, University of the Western Cape, Private Bag X17, Bellville, 7535, South Africa.
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Tang J, Song X, Ji G, Wu H, Sun S, Lu S, Li Y, Zhang C, Zhang H. A novel mutation in the DYSF gene in a patient with a presumed inflammatory myopathy. Neuropathology 2018; 38:433-437. [PMID: 29799141 DOI: 10.1111/neup.12474] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2018] [Revised: 04/05/2018] [Accepted: 04/09/2018] [Indexed: 01/30/2023]
Abstract
Dysferlinopathy, a progressive muscular dystrophy, results from mutations in the Dysferlin gene (DYSF, MIM*603009). Traditional diagnosis relies on the reduction or absence of dysferlin. However, altered dysferlin has been observed in other myopathies, leading to a precise diagnosis through molecular genetics. In this study, we report a patient who was previously misdiagnosed as inflammatory myopathy based on routine clinicopathological examinations alone. However, muscle biopsy specimens were analyzed further by immunohistochemistry of muscular dystrophy-related proteins, and gene-targeted next generation sequencing (NGS) was used to correctly identify muscular dystrophy. DNA was sequenced with NGS and the detected mutation was verified by Sanger sequencing. Our targeted NGS found a novel missense mutation (c.5392G > A) in the DYSF gene, allowing correct diagnosis of LGMD2B in our patient. We discovered of a novel missense mutation in the DYSF gene and have broadened the DYSF mutation spectrum, which may be correlated in patients with presumed dysferlinopathy, especially when lymphocytic infiltration is observed.
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Affiliation(s)
- Jin Tang
- Department of Neurology, The Second Hospital of Hebei Medical University, Shijiahzuang, China
| | - Xueqin Song
- Department of Neurology, The Second Hospital of Hebei Medical University, Shijiahzuang, China
| | - Guang Ji
- Department of Neurology, The Second Hospital of Hebei Medical University, Shijiahzuang, China
| | - Hongran Wu
- Department of Neurology, The Second Hospital of Hebei Medical University, Shijiahzuang, China
| | - Shuyan Sun
- Department of Neurology, The Second Hospital of Hebei Medical University, Shijiahzuang, China
| | - Shan Lu
- Department of Neurology, The Second Hospital of Hebei Medical University, Shijiahzuang, China
| | - Yuan Li
- Department of Neurology, The Second Hospital of Hebei Medical University, Shijiahzuang, China
| | - Chi Zhang
- Department of Neurology, The Second Hospital of Hebei Medical University, Shijiahzuang, China
| | - Huiqing Zhang
- Department of Neurology, The Second Hospital of Hebei Medical University, Shijiahzuang, China
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Treatment with Recombinant Human MG53 Protein Increases Membrane Integrity in a Mouse Model of Limb Girdle Muscular Dystrophy 2B. Mol Ther 2017; 25:2360-2371. [PMID: 28750735 DOI: 10.1016/j.ymthe.2017.06.025] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2016] [Revised: 06/23/2017] [Accepted: 06/28/2017] [Indexed: 12/20/2022] Open
Abstract
Limb girdle muscular dystrophy type 2B (LGMD2B) and other dysferlinopathies are degenerative muscle diseases that result from mutations in the dysferlin gene and have limited treatment options. The dysferlin protein has been linked to multiple cellular functions including a Ca2+-dependent membrane repair process that reseals disruptions in the sarcolemmal membrane. Recombinant human MG53 protein (rhMG53) can increase the membrane repair process in multiple cell types both in vitro and in vivo. Here, we tested whether rhMG53 protein can improve membrane repair in a dysferlin-deficient mouse model of LGMD2B (B6.129-Dysftm1Kcam/J). We found that rhMG53 can increase the integrity of the sarcolemmal membrane of isolated muscle fibers and whole muscles in a Ca2+-independent fashion when assayed by a multi-photon laser wounding assay. Intraperitoneal injection of rhMG53 into mice before acute eccentric treadmill exercise can decrease the release of intracellular enzymes from skeletal muscle and decrease the entry of immunoglobulin G and Evans blue dye into muscle fibers in vivo. These results indicate that short-term rhMG53 treatment can ameliorate one of the underlying defects in dysferlin-deficient muscle by increasing sarcolemmal membrane integrity. We also provide evidence that rhMG53 protein increases membrane integrity independently of the canonical dysferlin-mediated, Ca2+-dependent pathway known to be important for sarcolemmal membrane repair.
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10
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Fanin M, Angelini C. Progress and challenges in diagnosis of dysferlinopathy. Muscle Nerve 2016; 54:821-835. [DOI: 10.1002/mus.25367] [Citation(s) in RCA: 53] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/04/2016] [Indexed: 01/22/2023]
Affiliation(s)
- Marina Fanin
- Department of Neurosciences; University of Padova; Biomedical Campus “Pietro d'Abano”, via Giuseppe Orus 2B 35129 Padova Italy
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Blazek AD, Paleo BJ, Weisleder N. Plasma Membrane Repair: A Central Process for Maintaining Cellular Homeostasis. Physiology (Bethesda) 2016; 30:438-48. [PMID: 26525343 DOI: 10.1152/physiol.00019.2015] [Citation(s) in RCA: 62] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Plasma membrane repair is a conserved cellular response mediating active resealing of membrane disruptions to maintain homeostasis and prevent cell death and progression of multiple diseases. Cell membrane repair repurposes mechanisms from various cellular functions, including vesicle trafficking, exocytosis, and endocytosis, to mend the broken membrane. Recent studies increased our understanding of membrane repair by establishing the molecular machinery contributing to membrane resealing. Here, we review some of the key proteins linked to cell membrane repair.
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Affiliation(s)
- Alisa D Blazek
- Department of Physiology and Cell Biology, Davis Heart and Lung Research Institute, The Ohio State University Wexner Medical Center, Columbus, Ohio
| | - Brian J Paleo
- Department of Physiology and Cell Biology, Davis Heart and Lung Research Institute, The Ohio State University Wexner Medical Center, Columbus, Ohio
| | - Noah Weisleder
- Department of Physiology and Cell Biology, Davis Heart and Lung Research Institute, The Ohio State University Wexner Medical Center, Columbus, Ohio
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Petersen JA, Kuntzer T, Fischer D, von der Hagen M, Huebner A, Kana V, Lobrinus JA, Kress W, Rushing EJ, Sinnreich M, Jung HH. Dysferlinopathy in Switzerland: clinical phenotypes and potential founder effects. BMC Neurol 2015; 15:182. [PMID: 26444858 PMCID: PMC4596355 DOI: 10.1186/s12883-015-0449-3] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2015] [Accepted: 09/29/2015] [Indexed: 11/25/2022] Open
Abstract
Background Dysferlin is reduced in patients with limb girdle muscular dystrophy type 2B, Miyoshi myopathy, distal anterior compartment myopathy, and in certain Ethnic clusters. Methods We evaluated clinical and genetic patient data from three different Swiss Neuromuscular Centers. Results Thirteen patients from 6 non-related families were included. Age of onset was 18.8 ± 4.3 years. In all patients, diallelic disease-causing mutations were identified in the DYSF gene. Nine patients from 3 non-related families from Central Switzerland carried the identical homozygous mutation, c.3031 + 2T>C. A possible founder effect was confirmed by haplotype analysis. Three patients from two different families carried the heterozygous mutation, c.1064_1065delAA. Two novel mutations were identified (c.2869C>T (p.Gln957Stop), c.5928G>A (p.Trp1976Stop)). Conclusions Our study confirms the phenotypic heterogeneity associated with DYSF mutations. Two mutations (c.3031 + 2T>C, c.1064_1065delAA) appear common in Switzerland. Haplotype analysis performed on one case (c. 3031 + 2T>C) suggested a possible founder effect.
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Affiliation(s)
- Jens A Petersen
- Department of Neurology, University Hospital Zürich, Frauenklinikstrasse 26, 8091, Zürich, Switzerland.
| | - Thierry Kuntzer
- Nerve-Muscle Unit, Neurology Service, Department of Clinical Neurosciences, Lausanne University Hospital (CHUV), Lausanne, Switzerland.
| | - Dirk Fischer
- Department of Neurology, University Hospital Basel, Basel, Switzerland.
| | | | - Angela Huebner
- Klinik für Kinder- und Jugendmedizin, Medizinische Fakultät Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany.
| | - Veronika Kana
- Institute of Neuropathology, University Hospital Zürich, Zürich, Switzerland.
| | | | - Wolfram Kress
- Institure of Human Genetics, University of Würzburg, Würzburg, Germany.
| | - Elisabeth J Rushing
- Institute of Neuropathology, University Hospital Zürich, Zürich, Switzerland.
| | - Michael Sinnreich
- Department of Neurology, University Hospital Basel, Basel, Switzerland.
| | - Hans H Jung
- Department of Neurology, University Hospital Zürich, Frauenklinikstrasse 26, 8091, Zürich, Switzerland.
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Test 1: Treatment of dysferlinopathy with deflazacort: a double-blind, placebo-controlled clinical trial. Gene X 2015. [DOI: 10.1016/s0378-1119(15)30104-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
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Stehlíková K, Skálová D, Zídková J, Mrázová L, Vondráček P, Mazanec R, Voháňka S, Haberlová J, Hermanová M, Zámečník J, Souček O, Ošlejšková H, Dvořáčková N, Solařová P, Fajkusová L. Autosomal recessive limb-girdle muscular dystrophies in the Czech Republic. BMC Neurol 2014; 14:154. [PMID: 25135358 PMCID: PMC4145250 DOI: 10.1186/s12883-014-0154-7] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2014] [Accepted: 07/21/2014] [Indexed: 01/21/2023] Open
Abstract
Background Autosomal recessive limb-girdle muscular dystrophies (LGMD2) include a number of disorders with heterogeneous etiology that cause predominantly weakness and wasting of the shoulder and pelvic girdle muscles. In this study, we determined the frequency of LGMD subtypes within a cohort of Czech LGMD2 patients using mutational analysis of the CAPN3, FKRP, SGCA, and ANO5 genes. Methods PCR-sequencing analysis; sequence capture and targeted resequencing. Results Mutations of the CAPN3 gene are the most common cause of LGMD2, and mutations in this gene were identified in 71 patients in a set of 218 Czech probands with a suspicion of LGMD2. Totally, we detected 37 different mutations of which 12 have been described only in Czech LGMD2A patients. The mutation c.550delA is the most frequent among our LGMD2A probands and was detected in 47.1% of CAPN3 mutant alleles. The frequency of particular forms of LGMD2 was 32.6% for LGMD2A (71 probands), 4.1% for LGMD2I (9 probands), 2.8% for LGMD2D (6 probands), and 1.4% for LGMD2L (3 probands). Further, we present the first results of a new approach established in the Czech Republic for diagnosis of neuromuscular diseases: sequence capture and targeted resequencing. Using this approach, we identified patients with mutations in the DYSF and SGCB genes. Conclusions We characterised a cohort of Czech LGMD2 patients on the basis of mutation analysis of genes associated with the most common forms of LGMD2 in the European population and subsequently compared the occurrence of particular forms of LGMD2 among countries on the basis of our results and published studies.
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Affiliation(s)
| | | | | | | | | | | | | | | | | | | | | | | | | | | | - Lenka Fajkusová
- Centre of Molecular Biology and Gene Therapy, University Hospital Brno, Černopolní 9, Brno, 613 00, Czech Republic.
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15
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Muscular dystrophy in dysferlin-deficient mouse models. Neuromuscul Disord 2013; 23:377-87. [DOI: 10.1016/j.nmd.2013.02.004] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2012] [Revised: 01/09/2013] [Accepted: 02/05/2013] [Indexed: 11/17/2022]
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Terrill JR, Radley-Crabb HG, Iwasaki T, Lemckert FA, Arthur PG, Grounds MD. Oxidative stress and pathology in muscular dystrophies: focus on protein thiol oxidation and dysferlinopathies. FEBS J 2013; 280:4149-64. [PMID: 23332128 DOI: 10.1111/febs.12142] [Citation(s) in RCA: 130] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2012] [Revised: 01/14/2013] [Accepted: 01/15/2013] [Indexed: 12/23/2022]
Abstract
The muscular dystrophies comprise more than 30 clinical disorders that are characterized by progressive skeletal muscle wasting and degeneration. Although the genetic basis for many of these disorders has been identified, the exact mechanism for pathogenesis generally remains unknown. It is considered that disturbed levels of reactive oxygen species (ROS) contribute to the pathology of many muscular dystrophies. Reactive oxygen species and oxidative stress may cause cellular damage by directly and irreversibly damaging macromolecules such as proteins, membrane lipids and DNA; another major cellular consequence of reactive oxygen species is the reversible modification of protein thiol side chains that may affect many aspects of molecular function. Irreversible oxidative damage of protein and lipids has been widely studied in Duchenne muscular dystrophy, and we have recently identified increased protein thiol oxidation in dystrophic muscles of the mdx mouse model for Duchenne muscular dystrophy. This review evaluates the role of elevated oxidative stress in Duchenne muscular dystrophy and other forms of muscular dystrophies, and presents new data that show significantly increased protein thiol oxidation and high levels of lipofuscin (a measure of cumulative oxidative damage) in dysferlin-deficient muscles of A/J mice at various ages. The significance of this elevated oxidative stress and high levels of reversible thiol oxidation, but minimal myofibre necrosis, is discussed in the context of the disease mechanism for dysferlinopathies, and compared with the situation for dystrophin-deficient mdx mice.
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Affiliation(s)
- Jessica R Terrill
- School of Anatomy, Physiology and Human Biology, University of Western Australia, Perth, Western Australia, Australia
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Treatment of dysferlinopathy with deflazacort: a double-blind, placebo-controlled clinical trial. Orphanet J Rare Dis 2013; 8:26. [PMID: 23406536 PMCID: PMC3617000 DOI: 10.1186/1750-1172-8-26] [Citation(s) in RCA: 64] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2012] [Accepted: 02/10/2013] [Indexed: 11/18/2022] Open
Abstract
Background Dysferlinopathies are autosomal recessive disorders caused by mutations in the dysferlin (DYSF) gene encoding the dysferlin protein. DYSF mutations lead to a wide range of muscular phenotypes, with the most prominent being Miyoshi myopathy (MM) and limb girdle muscular dystrophy type 2B (LGMD2B). Methods We assessed the one-year-natural course of dysferlinopathy, and the safety and efficacy of deflazacort treatment in a double-blind, placebo-controlled cross-over trial. After one year of natural course without intervention, 25 patients with genetically defined dysferlinopathy were randomized to receive deflazacort and placebo for six months each (1 mg/kg/day in month one, 1 mg/kg every 2nd day during months two to six) in one of two treatment sequences. Results During one year of natural course, muscle strength declined about 2% as measured by CIDD (Clinical Investigation of Duchenne Dystrophy) score, and 76 Newton as measured by hand-held dynamometry. Deflazacort did not improve muscle strength. In contrast, there is a trend of worsening muscle strength under deflazacort treatment, which recovers after discontinuation of the study drug. During deflazacort treatment, patients showed a broad spectrum of steroid side effects. Conclusion Deflazacort is not an effective therapy for dysferlinopathies, and off-label use is not warranted. This is an important finding, since steroid treatment should not be administered in patients with dysferlinopathy, who may be often misdiagnosed as polymyositis. Trial registration This clinical trial was registered at http://www.ClincalTrials.gov, identifier: NCT00527228, and was always freely accessible to the public.
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18
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Rosales XQ, al-Dahhak R, Tsao CY. Childhood onset of limb-girdle muscular dystrophy. Pediatr Neurol 2012; 46:13-23. [PMID: 22196486 DOI: 10.1016/j.pediatrneurol.2011.08.014] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/12/2011] [Accepted: 08/25/2011] [Indexed: 01/16/2023]
Abstract
Limb-girdle muscular dystrophies comprise a rare heterogeneous group of genetic muscular dystrophies, involving 15 autosomal recessive subtypes and seven autosomal dominant subtypes. Autosomal recessive dystrophy is far more common than autosomal dominant dystrophy. Typical clinical features include progressive limb muscle weakness and atrophy (proximal greater than distal), varying from very mild to severe. Significant overlap of clinical phenotypes, with genetic and clinical heterogeneity, constitutes the rule for this group of diseases. Muscle biopsies are useful for histopathologic and immunolabeling studies, and DNA analysis is the gold standard to establish the specific form of muscular dystrophy. A definitive diagnosis among various subtypes is challenging, and the data presented here provide neuromuscular clinicians with additional information to help attain that goal.
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Affiliation(s)
- Xiomara Q Rosales
- Neuromuscular Division, Department of Pediatrics, Nationwide Children's Hospital, Columbus, Ohio, USA
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19
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Rosales XQ, Gastier-Foster JM, Lewis S, Vinod M, Thrush DL, Astbury C, Pyatt R, Reshmi S, Sahenk Z, Mendell JR. Novel diagnostic features of dysferlinopathies. Muscle Nerve 2010; 42:14-21. [PMID: 20544924 DOI: 10.1002/mus.21650] [Citation(s) in RCA: 62] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
Reports of dysferlinopathy have suggested a clinically heterogeneous group of patients. We identified specific novel molecular and phenotypic features that help distinguish dysferlinopathies from other forms of limb-girdle muscular dystrophy (LGMD). A detailed history, physical exam, and protein and mutation analysis of genomic DNA was done for all subjects. Five of 21 confirmed DYSF gene mutations were not previously reported. A distinct "bulge" of the deltoid muscle in combination with other findings was a striking feature in all patients. Six subjects had atypical calf enlargement, and 3 of these exhibited a paradoxical pattern of dysferlin expression: severely reduced by direct immunofluorescence with overexpression on Western blots. Six patients showed amyloid deposits in muscle that extended these findings to new domains of the dysferlin gene, including the C2G domain. Correlative studies showed colocalization of amyloid with deposition of dysferlin. The present data further serve to guide clinicians facing the expensive task of molecular characterization of patients with an LGMD phenotype.
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Affiliation(s)
- Xiomara Q Rosales
- Department of Pediatrics, Neuromuscular Division, Nationwide Children's Hospital, Columbus, Ohio, USA
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20
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Private dysferlin exon skipping mutation (c.5492G>A) with a founder effect reveals further alternative splicing involving exons 49-51. J Hum Genet 2010; 55:546-9. [PMID: 20535123 DOI: 10.1038/jhg.2010.60] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The allelic muscle disorders known as limb-girdle muscular dystrophy type 2B (LGMD2B), Miyoshi myopathy and distal anterior compartment myopathy result from defects in dysferlin-a sarcolemma-associated protein involved in membrane repair. Mutation screening in the dysferlin gene (DYSF) enabled the identification of seven Portuguese patients presenting the variant c.5492G>A, which was observed to promote skipping of exon 49 (p.Gly1802ValfsX17). Several residually expressed products of alternative splicing also involving exons 50 and 51 were detected in the leukocytes and muscle of both patients and normal controls. Quantitative transcript analysis confirmed these results and revealed that Delta49/Delta50 transcripts were predominant in blood. Although the patients were apparently unrelated, the c.5492G>A mutation was found in linkage disequilibrium with a particularly rare haplotype in the population, corroborating the hypothesis of a common origin. Despite the presence of the same mutation on the same haplotype background, onset of the disease was heterogeneous, with either proximal or distal muscle involvement.
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21
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Therrien C, Dodig D, Karpati G, Sinnreich M. Mutation impact on dysferlin inferred from database analysis and computer-based structural predictions. J Neurol Sci 2006; 250:71-8. [PMID: 16996541 DOI: 10.1016/j.jns.2006.07.004] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2006] [Revised: 07/06/2006] [Accepted: 07/09/2006] [Indexed: 10/24/2022]
Abstract
Dysferlin is a large sarcolemmal protein implicated in the repair of surface membrane tears in muscle cells. Mutations in dysferlin result in limb girdle muscular dystrophy type 2B and Miyoshi myopathy. Using a cDNA based approach we identified eight new pathogenic dysferlin alleles. To better understand how missense mutations could lead to reduced or absent dysferlin expression levels, we mapped missense mutations from our own and from published databases (n=55) to the secondary protein structure of dysferlin, deduced by computerized structural prediction tools. We found the protein to be very sensitive to the alteration of residues that were predicted to be buried inside the protein structure. We identified seven putative C2 domains, one more than commonly reported, of both type I and type II topology in dysferlin. Missense mutations often affected those structures as well as residues that were highly conserved between members of the ferlin family. Thus, alteration of structurally important residues in dysferlin could lead to improper folding and degradation of the mutant protein.
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MESH Headings
- Adolescent
- Adult
- Amino Acid Sequence/genetics
- Child
- Conserved Sequence
- DNA Mutational Analysis
- DNA, Complementary/analysis
- Dysferlin
- Evolution, Molecular
- Genetic Predisposition to Disease/genetics
- Humans
- Membrane Proteins/chemistry
- Membrane Proteins/genetics
- Molecular Sequence Data
- Muscle Proteins/chemistry
- Muscle Proteins/genetics
- Muscle, Skeletal/metabolism
- Muscle, Skeletal/physiopathology
- Muscular Dystrophies, Limb-Girdle/genetics
- Muscular Dystrophies, Limb-Girdle/metabolism
- Muscular Dystrophies, Limb-Girdle/physiopathology
- Mutation, Missense/genetics
- Phylogeny
- Protein Folding
- Protein Structure, Quaternary/genetics
- Protein Structure, Tertiary/genetics
- Proteomics
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Affiliation(s)
- Christian Therrien
- Montreal Neurological Institute, McGill University, 3801 University Street, Montreal, Quebec Canada H3A 2B4
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22
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Sinnreich M, Therrien C, Karpati G. Lariat branch point mutation in the dysferlin gene with mild limb-girdle muscular dystrophy. Neurology 2006; 66:1114-6. [PMID: 16606933 DOI: 10.1212/01.wnl.0000204358.89303.81] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
The authors report a genotype-phenotype correlation in a limb-girdle muscular dystrophy 2B family. Two severely affected sisters were homozygous for a dysferlin null mutation. Their mildly affected compound heterozygous mother harbored, in addition to one null allele, an in-frame exon-skipping allele caused by a novel lariat branch point mutation. The dysferlin molecule arising from the latter allele appeared to partially complement the null mutation, likely accounting for the mother's mild phenotype.
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Affiliation(s)
- Michael Sinnreich
- Montreal Neurological Institute, McGill University, Montreal, Quebec, Canada.
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23
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Nagashima T, Chuma T, Mano Y, Goto YI, Hayashi YK, Minami N, Nishino I, Nonaka I, Takahashi T, Sawa H, Aoki M, Nagashima K. Dysferlinopathy associated with rigid spine syndrome. Neuropathology 2005; 24:341-6. [PMID: 15641596 DOI: 10.1111/j.1440-1789.2004.00573.x] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Dysferlinopathy and rigid spine syndrome occurring in a 50-year-old man is reported. The patient noticed stiffness of knee and ankle joints, which gradually extended to neck, wrist and elbow joints leading to difficulty in anterior flexion. Muscular weakness and wasting of the lower extremities had developed since age 40, accompanied by a limitation of anterior bending of the spine. Elevated serum CK was noticed. Muscle CT revealed atrophy with moderate fatty replacement of muscles in the neck, shoulder and pelvic girdle, and marked replacement in the para-vertebral muscles, posterior compartment of hamstrings and calf muscles. Electromyography showed a typical myogenic pattern, and muscle biopsy disclosed dystrophic changes, compatible with limb-girdle muscular dystrophy 2B. Loss of dysferlin expression was verified by immunohistochemistry, which was confirmed by a mini-multiplex Western blotting system. Gene analyses of the dysferlin gene disclosed compound heterozygotes for frameshift (G3016 + 1A) and a missense mutation (G3370T). This study might propose some clues to resolve the combination of musular dystrophies and rigid spine syndrome.
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Salani S, Lucchiari S, Fortunato F, Crimi M, Corti S, Locatelli F, Bossolasco P, Bresolin N, Comi GP. Developmental and tissue-specific regulation of a novel dysferlin isoform. Muscle Nerve 2004; 30:366-74. [PMID: 15318348 DOI: 10.1002/mus.20106] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Dysferlin plays an essential role in the muscle repair machinery, and its deficiency is associated with limb-girdle muscular dystrophy type 2B and with two different distal myopathies (Miyoshi myopathy and distal anterior compartment myopathy). Our aims were to characterize the pattern of dysferlin expression during myogenic cell differentiation and to assess possible differentially spliced isoforms of the DYSF gene. Human primary myogenic cells express a splice variant of dysferlin mRNA lacking exon 17 (Delta17), together with full-length dysferlin mRNA. Real-time polymerase chain reaction analysis of human myoblasts, myotubes, and normal skeletal muscle showed that Delta17 expression inversely correlates with muscle differentiation. Indeed, Delta17 is progressively replaced by the wild type as myoblast fusion proceeds, and it disappears in adult skeletal muscle. Conversely, Delta17 is the predominant dysferlin variant in mature peripheral nerve. Our findings suggest that the two proteins play different roles in myogenic cell differentiation and that dysferlin function in peripheral nerve might be accomplished by this novel isoform.
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Affiliation(s)
- Sabrina Salani
- Centro Dino Ferrari, Dipartimento di Scienze Neurologiche, Università degli Studi di Milano, Istituti di Ricovero e Cura a Carattere Scientifico Ospedale Maggiore Policlinico, 20122 Milan, Italy
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25
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Confalonieri P, Oliva L, Andreetta F, Lorenzoni R, Dassi P, Mariani E, Morandi L, Mora M, Cornelio F, Mantegazza R. Muscle inflammation and MHC class I up-regulation in muscular dystrophy with lack of dysferlin: an immunopathological study. J Neuroimmunol 2004; 142:130-6. [PMID: 14512171 DOI: 10.1016/s0165-5728(03)00255-8] [Citation(s) in RCA: 98] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Muscle inflammation is characteristic of inflammatory myopathies but also occurs in muscular dystrophy with lack of the sarcolemmal protein dysferlin. We quantified inflammatory cells and major histocompatibility complex (MHC) expression in muscle from 10 patients with dysferlinopathy. Infiltrating cells were always present although numbers varied considerably; macrophages were more common than T cells, T cytotoxicity was absent, and MHC class I was overexpressed on muscle fibers. These findings differ from polymyositis (PM) but are closely similar to those in SJL/J mice (which lack dysferlin) and emphasize the relationship between absence of dysferlin and immune system abnormalities in muscle.
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Affiliation(s)
- Paolo Confalonieri
- Department of Neuromuscular Diseases, Istituto Nazionale Neurologico Carlo Besta, via Celoria 11, 20133 Milan, Italy.
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26
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Cagliani R, Fortunato F, Giorda R, Rodolico C, Bonaglia MC, Sironi M, D'Angelo MG, Prelle A, Locatelli F, Toscano A, Bresolin N, Comi GP. Molecular analysis of LGMD-2B and MM patients: identification of novel DYSF mutations and possible founder effect in the Italian population. Neuromuscul Disord 2003; 13:788-95. [PMID: 14678801 DOI: 10.1016/s0960-8966(03)00133-0] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
Dysferlin, the protein product of the dysferlin gene (DYSF), has been shown to have a role in calcium-induced membrane fusion and repair. Dysferlin is absent or drastically reduced in patients with the following autosomal recessive disorders: limb-girdle muscular dystrophy type 2B (LGMD-2B), Miyoshi myopathy (MM) and distal anterior compartment myopathy. To date, less than 45 mutations have been described in DYSF and a wide inter- and intra-familial variation in clinical phenotype has been associated with the same mutation. This observation underlines the relevance of any new report describing genotype/phenotype correlations in dysferlinopathic patient and families. Here we present the results of clinical, biochemical and genetic analysis performed on one MM and three LGMD Italian families. By screening the entire coding region of DYSF, we identified three novel mutations (two missense substitutions and one frame shift microdeletion). The possible existence of a founder effect for the Arg959Trp mutation in the Italian population is discussed.
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Affiliation(s)
- R Cagliani
- IRCCS E. Medea, Associazione La Nostra Famiglia, Via Don Luigi Monza 20, 23842 Bosisio Parini (LC), Italy.
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27
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Davis DB, Doherty KR, Delmonte AJ, McNally EM. Calcium-sensitive phospholipid binding properties of normal and mutant ferlin C2 domains. J Biol Chem 2002; 277:22883-8. [PMID: 11959863 DOI: 10.1074/jbc.m201858200] [Citation(s) in RCA: 150] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Mutations in dysferlin, a novel membrane protein of unknown function, lead to muscular dystrophy. Myoferlin is highly homologous to dysferlin and like dysferlin is a plasma membrane protein with six C2 domains highly expressed in muscle. C2 domains are found in a variety of membrane-associated proteins where they have been implicated in calcium, phospholipid, and protein-binding. We investigated the pattern of dysferlin and myoferlin expression in a cell culture model of muscle development and found that dysferlin is expressed in mature myotubes. In contrast, myoferlin is highly expressed in elongated "prefusion" myoblasts and is decreased in mature myotubes where dysferlin expression is greatest. We tested ferlin C2 domains for their ability to bind phospholipid in a calcium-sensitive manner. We found that C2A, the first C2 domain of dysferlin and myoferlin, bound 50% phosphatidylserine and that phospholipid binding was regulated by calcium concentration. A dysferlin point mutation responsible for muscular dystrophy was engineered into the dysferlin C2A domain and demonstrated reduced calcium-sensitive phospholipid binding. Based on these data, we propose a mechanism for muscular dystrophy in which calcium-regulated phospholipid binding is abnormal, leading to defective maintenance and repair of muscle membranes.
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Affiliation(s)
- Dawn Belt Davis
- Department of Pathology, The University of Chicago, Chicago, Illinois 60637, USA
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28
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Abstract
The muscular dystrophies are inherited myogenic disorders characterised by progressive muscle wasting and weakness of variable distribution and severity. They can be subdivided into several groups, including congenital forms, in accordance with the distribution of predominant muscle weakness: Duchenne and Becker; Emery-Dreifuss; distal; facioscapulohumeral; oculopharyngeal; and limb-girdle which is the most heterogeneous group. In several dystrophies the heart can be seriously affected, sometimes in the absence of clinically significant weakness. The genes and their protein products that cause most of these disorders have now been identified. This information is essential to establish an accurate diagnosis and for reliable genetic counselling and prenatal diagnosis. There is, as yet, no way of greatly affecting the long-term course of any of these diseases. However, advances in gene manipulation and stem-cell therapy suggest cautious optimism for finding an effective treatment in the not-too-distant future.
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Affiliation(s)
- Alan E H Emery
- Peninsula Medical School, Department of Neurology, Royal Devon and Exeter Hospital, Exeter EX2 5DW, UK.
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