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Functional analysis of variants in DMD exon/intron 10 predicted to affect splicing. J Hum Genet 2022; 67:495-501. [DOI: 10.1038/s10038-022-01035-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2021] [Revised: 03/08/2022] [Accepted: 03/31/2022] [Indexed: 11/08/2022]
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Becker muscular dystrophy: case report, review of the literature, and analysis of differentially expressed hub genes. Neurol Sci 2021; 43:243-253. [PMID: 34731335 DOI: 10.1007/s10072-021-05499-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2021] [Accepted: 07/21/2021] [Indexed: 10/19/2022]
Abstract
INTRODUCTION Becker muscular dystrophy (BMD) is a genetic and progressive neuromuscular disease caused by mutations in the dystrophin gene with no available cure. A case report and comprehensive review of BMD cases aim to provide important clues for early diagnosis and implications for clinical practice. Genes and pathways identified from microarray data of muscle samples from patients with BMD help uncover the potential mechanism and provide novel therapeutic targets for dystrophin-deficient muscular dystrophies. METHODS We describe a BMD family with a 10-year-old boy as the proband and reviewed BMD cases from PubMed. Datasets from the Gene Expression Omnibus database were downloaded and integrated with the online software. RESULTS The systematic review revealed the clinical manifestations and mutation points of the dystrophin gene. Gene ontology analysis showed that extracellular matrix organization and extracellular structure organization with enrichment of upregulated genes coexist in three datasets. We present the first report of TUBA1A involvement in the development of BMD/Duchenne muscular dystrophy (DMD). DISCUSSION This study provides important implications for clinical practice, uncovering the potential mechanism of the progress of BMD/DMD, and provided new therapeutic targets.
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Torella A, Zanobio M, Zeuli R, del Vecchio Blanco F, Savarese M, Giugliano T, Garofalo A, Piluso G, Politano L, Nigro V. The position of nonsense mutations can predict the phenotype severity: A survey on the DMD gene. PLoS One 2020; 15:e0237803. [PMID: 32813700 PMCID: PMC7437896 DOI: 10.1371/journal.pone.0237803] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2020] [Accepted: 08/03/2020] [Indexed: 12/23/2022] Open
Abstract
A nonsense mutation adds a premature stop signal that hinders any further translation of a protein-coding gene, usually resulting in a null allele. To investigate the possible exceptions, we used the DMD gene as an ideal model. First, because dystrophin absence causes Duchenne muscular dystrophy (DMD), while its reduction causes Becker muscular dystrophy (BMD). Second, the DMD gene is X-linked and there is no second allele that can interfere in males. Third, databases are accumulating reports on many mutations and phenotypic data. Finally, because DMD mutations may have important therapeutic implications. For our study, we analyzed large databases (LOVD, HGMD and ClinVar) and literature and revised critically all data, together with data from our internal patients. We totally collected 2593 patients. Positioning these mutations along the dystrophin transcript, we observed a nonrandom distribution of BMD-associated mutations within selected exons and concluded that the position can be predictive of the phenotype. Nonsense mutations always cause DMD when occurring at any point in fifty-one exons. In the remaining exons, we found milder BMD cases due to early 5’ nonsense mutations, if reinitiation can occur, or due to late 3’ nonsense when the shortened product retains functionality. In the central part of the gene, all mutations in some in-frame exons, such as in exons 25, 31, 37 and 38 cause BMD, while mutations in exons 30, 32, 34 and 36 cause DMD. This may have important implication in predicting the natural history and the efficacy of therapeutic use of drug-stimulated translational readthrough of premature termination codons, also considering the action of internal natural rescuers. More in general, our survey confirm that a nonsense mutation should be not necessarily classified as a null allele and this should be considered in genetic counselling.
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Affiliation(s)
- Annalaura Torella
- Dipartimento di Medicina di Precisione, Università degli Studi della Campania “Luigi Vanvitelli”, Napoli, Italy
- Telethon Institute of Genetics and Medicine (TIGEM), Pozzuoli, Italy
| | - Mariateresa Zanobio
- Dipartimento di Medicina di Precisione, Università degli Studi della Campania “Luigi Vanvitelli”, Napoli, Italy
| | - Roberta Zeuli
- Dipartimento di Medicina di Precisione, Università degli Studi della Campania “Luigi Vanvitelli”, Napoli, Italy
| | | | - Marco Savarese
- Dipartimento di Medicina di Precisione, Università degli Studi della Campania “Luigi Vanvitelli”, Napoli, Italy
- Folkhälsan Research Center, Medicum, University of Helsinki, Helsinki, Finland
| | - Teresa Giugliano
- Dipartimento di Medicina di Precisione, Università degli Studi della Campania “Luigi Vanvitelli”, Napoli, Italy
| | - Arcomaria Garofalo
- Dipartimento di Medicina di Precisione, Università degli Studi della Campania “Luigi Vanvitelli”, Napoli, Italy
| | - Giulio Piluso
- Dipartimento di Medicina di Precisione, Università degli Studi della Campania “Luigi Vanvitelli”, Napoli, Italy
| | - Luisa Politano
- Dipartimento di Medicina Sperimentale, Università degli Studi della Campania “Luigi Vanvitelli”, Napoli, Italy
| | - Vincenzo Nigro
- Dipartimento di Medicina di Precisione, Università degli Studi della Campania “Luigi Vanvitelli”, Napoli, Italy
- Telethon Institute of Genetics and Medicine (TIGEM), Pozzuoli, Italy
- * E-mail:
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Hamaguchi M, Fujita H, Suzuki K, Nakamura T, Nishino I, Hirata K. [A male patient with adult-onset sporadic calpainopathy presenting with hypertrophy of the upper extremities]. Rinsho Shinkeigaku 2019; 59:740-745. [PMID: 31656265 DOI: 10.5692/clinicalneurol.cn-001330] [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: 11/05/2022]
Abstract
A 33-year-old man presented with slowly progressive weakness in the lower extremities over 8 years. At the age of 16 years, the elevation of serum creatine kinase level was detected. Physical examination revealed scapular winging, exaggerated lumbar lordosis and tendoachilles contracture. Gowers sign was positive and proximal dominant limb weakness was noted. Hypertrophy was observed in the upper limbs such as the biceps brachii and forearm flexor muscles. Muscle biopsy showed distinct differences in size of muscle fibers and regenerating and necrotic muscle fibers. A histological study revealed decreased calpain3 expression. Gene analysis of CAPN3 revealed two known gene mutations, leading to a diagnosis of calpainopathy (limb girdle muscular dystrophy 2A; LGMD2A). We here report our patient to discuss findings of upper limb hypertrophy, which are frequently missed compared to the lower limb, but important clinical findings.
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Affiliation(s)
| | | | | | | | - Ichizo Nishino
- Department of Neuromuscular Research, National Institute of Neurology, National Center of Neurology and Psychiatry.,Department of Clinical Genome Analysis, Medical Genome Center, National Center of Neurology and Psychiatry
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Løkken N, Hedermann G, Thomsen C, Vissing J. Contractile properties are disrupted in Becker muscular dystrophy, but not in limb girdle type 2I. Ann Neurol 2016; 80:466-71. [PMID: 27463532 DOI: 10.1002/ana.24743] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2016] [Revised: 07/14/2016] [Accepted: 07/24/2016] [Indexed: 12/16/2022]
Abstract
We investigated whether a linear relationship between muscle strength and cross-sectional area (CSA) is preserved in calf muscles of patients with Becker muscular dystrophy (BMD, n = 14) and limb-girdle type 2I muscular dystrophy (LGMD2I, n = 11), before and after correcting for muscle fat infiltration. The Dixon magnetic resonance imaging technique was used to quantify fat and calculate a fat-free contractile CSA. Strength was assessed by dynamometry. Muscle strength/CSA relationships were significantly lower in patients versus controls. The strength/contractile-CSA relationship was still severely lowered in BMD, but was almost normalized in LGMD2I. Our findings suggest close to intact contractile properties in LGMD2I, which are severely disrupted in BMD. Ann Neurol 2016;80:466-471.
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Affiliation(s)
| | | | - Carsten Thomsen
- Department of Diagnostic Radiology, Rigshospitalet, Copenhagen University Hospital, Copenhagen, Denmark
| | - John Vissing
- Copenhagen Neuromuscular Center, Copenhagen, Denmark.
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6
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Toh ZYC, Thandar Aung-Htut M, Pinniger G, Adams AM, Krishnaswarmy S, Wong BL, Fletcher S, Wilton SD. Deletion of Dystrophin In-Frame Exon 5 Leads to a Severe Phenotype: Guidance for Exon Skipping Strategies. PLoS One 2016; 11:e0145620. [PMID: 26745801 PMCID: PMC4706350 DOI: 10.1371/journal.pone.0145620] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2015] [Accepted: 12/07/2015] [Indexed: 12/03/2022] Open
Abstract
Duchenne and Becker muscular dystrophy severity depends upon the nature and location of the DMD gene lesion and generally correlates with the dystrophin open reading frame. However, there are striking exceptions where an in-frame genomic deletion leads to severe pathology or protein-truncating mutations (nonsense or frame-shifting indels) manifest as mild disease. Exceptions to the dystrophin reading frame rule are usually resolved after molecular diagnosis on muscle RNA. We report a moderate/severe Becker muscular dystrophy patient with an in-frame genomic deletion of DMD exon 5. This mutation has been reported by others as resulting in Duchenne or Intermediate muscular dystrophy, and the loss of this in-frame exon in one patient led to multiple splicing events, including omission of exon 6, that disrupts the open reading frame and is consistent with a severe phenotype. The patient described has a deletion of dystrophin exon 5 that does not compromise recognition of exon 6, and although the deletion does not disrupt the reading frame, his clinical presentation is more severe than would be expected for classical Becker muscular dystrophy. We suggest that the dystrophin isoform lacking the actin-binding sequence encoded by exon 5 is compromised, reflected by the phenotype resulting from induction of this dystrophin isoform in mouse muscle in vivo. Hence, exon skipping to address DMD-causing mutations within DMD exon 5 may not yield an isoform that confers marked clinical benefit. Additional studies will be required to determine whether multi-exon skipping strategies could yield more functional dystrophin isoforms, since some BMD patients with larger in-frame deletions in this region have been reported with mild phenotypes.
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Affiliation(s)
- Zhi Yon Charles Toh
- Western Australian Neuroscience Research Institute, Perth, Australia
- University of Western Australia, Perth, Australia
| | | | - Gavin Pinniger
- School of Anatomy, Physiology and Human Biology, University of Western Australia, Perth, Australia
| | - Abbie M. Adams
- Western Australian Neuroscience Research Institute, Perth, Australia
- University of Western Australia, Perth, Australia
- Centre for Comparative Genomics, Murdoch University, Perth, Australia
| | | | - Brenda L. Wong
- Department of Paediatrics, Department of Neurology, Cincinnati Children’s Hospital Medical Center, Cincinnati, Ohio, United States of America
| | - Sue Fletcher
- Western Australian Neuroscience Research Institute, Perth, Australia
- University of Western Australia, Perth, Australia
- Centre for Comparative Genomics, Murdoch University, Perth, Australia
| | - Steve D. Wilton
- Western Australian Neuroscience Research Institute, Perth, Australia
- University of Western Australia, Perth, Australia
- Centre for Comparative Genomics, Murdoch University, Perth, Australia
- * E-mail:
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7
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Wilton SD, Veedu RN, Fletcher S. The emperor's new dystrophin: finding sense in the noise. Trends Mol Med 2015; 21:417-26. [PMID: 26051381 DOI: 10.1016/j.molmed.2015.04.006] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2015] [Revised: 04/29/2015] [Accepted: 04/30/2015] [Indexed: 01/16/2023]
Abstract
Targeted dystrophin exon removal is a promising therapy for Duchenne muscular dystrophy (DMD); however, dystrophin expression in some reports is not supported by the associated data. As in the account of 'The Emperor's New Clothes', the validity of such claims must be questioned, with critical re-evaluation of available data. Is it appropriate to report clinical benefit and induction of dystrophin as dose dependent when the baseline is unclear? The inability to induce meaningful levels of dystrophin does not mean that dystrophin expression as an end point is irrelevant, nor that induced exon skipping as a strategy is flawed, but demands that drug safety and efficacy, and study parameters be addressed, rather than questioning the strategy or the validity of dystrophin as a biomarker.
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Affiliation(s)
- S D Wilton
- Centre for Comparative Genomics, Murdoch University, 90 South Street, Murdoch, WA 6009, Australia; West Australian Neuroscience Research Institute, Murdoch University, 90 South Street, Murdoch, WA 6009, Australia.
| | - R N Veedu
- Centre for Comparative Genomics, Murdoch University, 90 South Street, Murdoch, WA 6009, Australia; West Australian Neuroscience Research Institute, Murdoch University, 90 South Street, Murdoch, WA 6009, Australia
| | - S Fletcher
- Centre for Comparative Genomics, Murdoch University, 90 South Street, Murdoch, WA 6009, Australia; West Australian Neuroscience Research Institute, Murdoch University, 90 South Street, Murdoch, WA 6009, Australia
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Lamandé SR, North KN. Activating internal ribosome entry to treat Duchenne muscular dystrophy. Nat Med 2014; 20:987-8. [PMID: 25198047 DOI: 10.1038/nm.3677] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Mutations in the DMD gene, encoding dystrophin, cause the most common forms of muscular dystrophy. A new study shows that forcing translation of DMD from an internal ribosome entry site can alleviate Duchenne muscular dystrophy symptoms in a mouse model.
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Affiliation(s)
- Shireen R Lamandé
- Murdoch Childrens Research Institute and Department of Paediatrics, University of Melbourne, Royal Children's Hospital, Melbourne, Victoria, Australia
| | - Kathryn N North
- Murdoch Childrens Research Institute and Department of Paediatrics, University of Melbourne, Royal Children's Hospital, Melbourne, Victoria, Australia
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Zatz M, Pavanello R, Lazar M, Yamamoto G, Lourenço N, Cerqueira A, Nogueira L, Vainzof M. Milder course in Duchenne patients with nonsense mutations and no muscle dystrophin. Neuromuscul Disord 2014; 24:986-9. [DOI: 10.1016/j.nmd.2014.06.003] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2014] [Accepted: 06/01/2014] [Indexed: 11/25/2022]
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10
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Wein N, Vulin A, Sofia Falzarano M, Al-Khalili Szigyarto C, Maiti B, Findlay A, Heller KN, Uhlén M, Bakthavachalu B, Messina S, Vita G, Passarelli C, Gualandi F, Wilton SD, Rodino-Klapac L, Yang L, Dunn DM, Schoenberg D, Weiss RB, Howard MT, Ferlini A, Flanigan KM. Translation from a DMD exon 5 IRES results in a functional dystrophin isoform that attenuates dystrophinopathy in humans and mice. Nat Med 2014; 20:992-1000. [PMID: 25108525 PMCID: PMC4165597 DOI: 10.1038/nm.3628] [Citation(s) in RCA: 89] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2014] [Accepted: 06/05/2014] [Indexed: 12/26/2022]
Abstract
Most mutations that truncate the reading frame of the DMD gene cause loss of dystrophin expression and lead to Duchenne muscular dystrophy. However, amelioration of disease severity has been shown to result from alternative translation initiation beginning in DMD exon 6 that leads to expression of a highly functional N-truncated dystrophin. Here we demonstrate that this isoform results from usage of an internal ribosome entry site (IRES) within exon 5 that is glucocorticoid inducible. We confirmed IRES activity by both peptide sequencing and ribosome profiling in muscle from individuals with minimal symptoms despite the presence of truncating mutations. We generated a truncated reading frame upstream of the IRES by exon skipping, which led to synthesis of a functional N-truncated isoform in both human subject-derived cell lines and in a new DMD mouse model, where expression of the truncated isoform protected muscle from contraction-induced injury and corrected muscle force to the same level as that observed in control mice. These results support a potential therapeutic approach for patients with mutations within the 5' exons of DMD.
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Affiliation(s)
- Nicolas Wein
- The Center for Gene Therapy, Nationwide Children’s Hospital; The Ohio State University, Columbus, Ohio, USA
| | - Adeline Vulin
- The Center for Gene Therapy, Nationwide Children’s Hospital; The Ohio State University, Columbus, Ohio, USA
| | - Maria Sofia Falzarano
- Section of Microbiology and Medical Genetics, Department of Medical Sciences, University of Ferrara, Ferrara, Italy
| | - Christina Al-Khalili Szigyarto
- Department of Proteomics and Nanobiotechnology, School of Biotechnology, KTH-Royal Institute of Technology, Stockholm, Sweden
| | - Baijayanta Maiti
- Department of Neurology, Washington University School of Medicine, St. Louis, Missouri
| | - Andrew Findlay
- The Center for Gene Therapy, Nationwide Children’s Hospital; The Ohio State University, Columbus, Ohio, USA
| | - Kristin N Heller
- The Center for Gene Therapy, Nationwide Children’s Hospital; The Ohio State University, Columbus, Ohio, USA
| | - Mathias Uhlén
- Department of Proteomics and Nanobiotechnology, School of Biotechnology, KTH-Royal Institute of Technology, Stockholm, Sweden
| | - Baskar Bakthavachalu
- Center for RNA Biology and Department of Molecular and Cellular Biochemistry, The Ohio State University, Columbus, Ohio, USA
| | - Sonia Messina
- Department of Neuroscience, University of Messina and Centro Clinico Nemo Sud, Messina, Italy
| | - Giuseppe Vita
- Department of Neuroscience, University of Messina and Centro Clinico Nemo Sud, Messina, Italy
| | | | - Francesca Gualandi
- Section of Microbiology and Medical Genetics, Department of Medical Sciences, University of Ferrara, Ferrara, Italy
| | - Steve D Wilton
- Centre for Comparative Genomics, Murdoch University, Perth, Australia
| | - Louise Rodino-Klapac
- The Center for Gene Therapy, Nationwide Children’s Hospital; The Ohio State University, Columbus, Ohio, USA
- Department of Pediatrics, The Ohio State University, Columbus, Ohio, USA
| | - Lin Yang
- Division of Biomedical Informatics, Department of Computer Science, University of Kentucky Lexington, Kentucky, USA
| | - Diane M. Dunn
- Department of Human Genetics, The University of Utah School of Medicine, Salt Lake City, Utah, USA
| | - Daniel Schoenberg
- Center for RNA Biology and Department of Molecular and Cellular Biochemistry, The Ohio State University, Columbus, Ohio, USA
| | - Robert B. Weiss
- Department of Human Genetics, The University of Utah School of Medicine, Salt Lake City, Utah, USA
| | - Michael T. Howard
- Department of Human Genetics, The University of Utah School of Medicine, Salt Lake City, Utah, USA
| | - Alessandra Ferlini
- Section of Microbiology and Medical Genetics, Department of Medical Sciences, University of Ferrara, Ferrara, Italy
| | - Kevin M. Flanigan
- The Center for Gene Therapy, Nationwide Children’s Hospital; The Ohio State University, Columbus, Ohio, USA
- Department of Pediatrics, The Ohio State University, Columbus, Ohio, USA
- Department of Neurology, The Ohio State University, Columbus, Ohio, USA
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Targeted exon skipping to correct exon duplications in the dystrophin gene. MOLECULAR THERAPY-NUCLEIC ACIDS 2014; 3:e155. [PMID: 24643206 PMCID: PMC3982197 DOI: 10.1038/mtna.2014.8] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/15/2013] [Accepted: 01/24/2014] [Indexed: 01/16/2023]
Abstract
Duchenne muscular dystrophy is a severe muscle-wasting disease caused by mutations in the dystrophin gene that ablate functional protein expression. Although exonic deletions are the most common Duchenne muscular dystrophy lesion, duplications account for 10-15% of reported disease-causing mutations, and exon 2 is the most commonly duplicated exon. Here, we describe the in vitro evaluation of phosphorodiamidate morpholino oligomers coupled to a cell-penetrating peptide and 2'-O-methyl phosphorothioate oligonucleotides, using three distinct strategies to reframe the dystrophin transcript in patient cells carrying an exon 2 duplication. Differences in exon-skipping efficiencies in vitro were observed between oligomer analogues of the same sequence, with the phosphorodiamidate morpholino oligomer coupled to a cell-penetrating peptide proving the most effective. Differences in exon 2 excision efficiency between normal and exon 2 duplication cells, were apparent, indicating that exon context influences oligomer-induced splice switching. Skipping of a single copy of exon 2 was induced in the cells carrying an exon 2 duplication, the simplest strategy to restore the reading frame and generate a normal dystrophin transcript. In contrast, multiexon skipping of exons 2-7 to generate a Becker muscular dystrophy-like dystrophin transcript was more challenging and could only be induced efficiently with the phosphorodiamidate morpholino oligomer chemistry.
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Witting N, Duno M, Petri H, Krag T, Bundgaard H, Kober L, Vissing J. Anoctamin 5 muscular dystrophy in Denmark: prevalence, genotypes, phenotypes, cardiac findings, and muscle protein expression. J Neurol 2013; 260:2084-93. [PMID: 23670307 DOI: 10.1007/s00415-013-6934-y] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2013] [Revised: 04/16/2013] [Accepted: 04/18/2013] [Indexed: 11/24/2022]
Abstract
Since the initial description in 2010 of anoctamin 5 deficiency as a cause of muscular dystrophy, a handful of papers have described this disease in cases of mixed populations. We report the first large regional study and present data on new aspects of prevalence, muscular and cardiac phenotypic characteristics, and muscle protein expression. All patients in our neuromuscular unit with genetically unclassified, recessive limb girdle muscular dystrophy (LGMD2), Miyoshi-type distal myopathy (MMD) or persistent asymptomatic hyperCK-emia (PACK) were assessed for mutations in the ANO5 gene. Genetically confirmed patients were evaluated with muscular and cardiopulmonary examination. Among 40 unclassified patients (28 LGMD2, 5 MMD, 7 PACK), 20 were homozygous or compound heterozygous for ANO5 mutations, (13 LGMD2, 5 MMD, 2 PACK). Prevalence of ANO5 deficiency in Denmark was estimated at 1:100.000 and ANO5 mutations caused 11 % of our total cohort of LGMD2 cases making it the second most common LGMD2 etiology in Denmark. Eight patients complained of dysphagia and 3 dated symptoms of onset in childhood. Cardiac examinations revealed increased frequency of premature ventricular contractions. Four novel putative pathogenic mutations were discovered. Total prevalence and distribution of phenotypes of ANO5 disease in a representative regional cohort are described for the first time. A high prevalence of ANO5 deficiency was found among patients with unclassified LGMD2 (46 %) and MMD (100 %). The high incidence of reported dysphagia is a new phenotypic feature not previously reported, and cardiac investigations revealed that ANO5-patients may have an increased risk of ventricular arrhythmia.
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Affiliation(s)
- Nanna Witting
- Neuromuscular Research Unit and Department of Neurology, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark.
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Flanigan KM, Wein N, Gurvich OL, Howard MT, Weiss RB. Becker muscular dystrophy with widespread muscle hypertrophy and a non-sense mutation of exon 2. Neuromuscul Disord 2013; 23:192. [PMID: 23369578 DOI: 10.1016/j.nmd.2012.11.012] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2012] [Accepted: 11/23/2012] [Indexed: 11/26/2022]
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