Long-range genomic map of the Duchenne muscular dystrophy (DMD) gene: Isolation and use of J66 (DXS268), a distal intragenic marker

Background: Increasing evidence suggests that Duchenne muscular dystrophy (DMD) gene is involved in the occurrence of different types of cancer. Moreover, development of sarcomas was reported in mdx mice, the murine model of DMD, in older age. So far, nine isolated DMD patients were reported with concomitant cancer, four of whom with rhabdomyosarcoma (RMS), but no systematic investigation was performed about the true incidence of cancer in DMD. Methods: All members of the Italian Association of Myology were asked about the occurrence of cancer in their DMD patients in the last 30 years. Results: Four DMD patients with cancer were reported after checking 2455 medical records. One developed brain tumour at the age of 35 years. Two patients had alveolar RMS at 14 and 17 years of age. The fourth patient had a benign enchondroma when 11-year-old. Conclusion: Prevalence of cancer in general in the Italian DMD patients does not seem to be different from that in the general population with the same age range. Although the small numbers herein presented do not allow definitive conclusion, the frequent occurrence of RMS in DMD patients raises an alert for basic researchers and clinicians. The role of DMD gene in cancer merits further investigations.

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Induced Pluripotent Stem Cells for Duchenne Muscular Dystrophy Modeling and Therapy

Cells ◽

10.3390/cells7120253 ◽

2018 ◽

Vol 7 (12) ◽

pp. 253 ◽

Cited By ~ 15

Author(s):

Lubos Danisovic ◽

Martina Culenova ◽

Maria Csobonyeiova

Keyword(s):

Duchenne Muscular Dystrophy ◽

Muscular Dystrophy ◽

Pluripotent Stem Cells ◽

Pluripotent Stem Cell ◽

Induced Pluripotent Stem Cell ◽

Cell Reprogramming ◽

Progressive Degeneration ◽

Cardiac Muscles ◽

Dmd Gene ◽

Induced Pluripotent

Duchenne muscular dystrophy (DMD) is an X-linked recessive disorder, caused by mutation of the DMD gene which encodes the protein dystrophin. This dystrophin defect leads to the progressive degeneration of skeletal and cardiac muscles. Currently, there is no effective therapy for this disorder. However, the technology of cell reprogramming, with subsequent controlled differentiation to skeletal muscle cells or cardiomyocytes, may provide a unique tool for the study, modeling, and treatment of Duchenne muscular dystrophy. In the present review, we describe current methods of induced pluripotent stem cell generation and discuss their implications for the study, modeling, and development of cell-based therapies for Duchenne muscular dystrophy.

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CRISPR-Generated Animal Models of Duchenne Muscular Dystrophy

Genes ◽

10.3390/genes11030342 ◽

2020 ◽

Vol 11 (3) ◽

pp. 342 ◽

Cited By ~ 1

Author(s):

Kenji Rowel Q. Lim ◽

Quynh Nguyen ◽

Kasia Dzierlega ◽

Yiqing Huang ◽

Toshifumi Yokota

Keyword(s):

Duchenne Muscular Dystrophy ◽

Muscular Dystrophy ◽

Animal Models ◽

Mechanical Stress ◽

Muscle Cell ◽

Neuromuscular Disorder ◽

Reading Frame ◽

Advantages And Disadvantages ◽

Short Palindromic Repeat ◽

Dmd Gene

Duchenne muscular dystrophy (DMD) is a fatal X-linked recessive neuromuscular disorder most commonly caused by mutations disrupting the reading frame of the dystrophin (DMD) gene. DMD codes for dystrophin, which is critical for maintaining the integrity of muscle cell membranes. Without dystrophin, muscle cells receive heightened mechanical stress, becoming more susceptible to damage. An active body of research continues to explore therapeutic treatments for DMD as well as to further our understanding of the disease. These efforts rely on having reliable animal models that accurately recapitulate disease presentation in humans. While current animal models of DMD have served this purpose well to some extent, each has its own limitations. To help overcome this, clustered regularly interspaced short palindromic repeat (CRISPR)-based technology has been extremely useful in creating novel animal models for DMD. This review focuses on animal models developed for DMD that have been created using CRISPR, their advantages and disadvantages as well as their applications in the DMD field.

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Duchenne muscular dystrophy: genome editing gives new hope for treatment

Postgraduate Medical Journal ◽

10.1136/postgradmedj-2017-135377 ◽

2018 ◽

Vol 94 (1111) ◽

pp. 296-304 ◽

Cited By ~ 2

Author(s):

Vassili Crispi ◽

Antonios Matsakas

Keyword(s):

Duchenne Muscular Dystrophy ◽

Muscular Dystrophy ◽

Genome Editing ◽

Genetic Diseases ◽

Wasting Disease ◽

Cardiac Muscles ◽

Dmd Gene ◽

Current Lines ◽

Dystrophin Protein ◽

Potential Therapeutics

Duchenne muscular dystrophy (DMD) is a progressive wasting disease of skeletal and cardiac muscles, representing one of the most common recessive fatal inherited genetic diseases with 1:3500–1:5000 in yearly incidence. It is caused by mutations in the DMD gene that encodes the membrane-associated dystrophin protein. Over the years, many have been the approaches to management of DMD, but despite all efforts, no effective treatment has yet been discovered. Hope for the development of potential therapeutics has followed the recent advances in genome editing and gene therapy. This review gives an overview to DMD and summarises current lines of evidence with regard to treatment and disease management alongside the appropriate considerations.

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238 TAILORED PIG MODEL OF DUCHENNE MUSCULAR DYSTROPHY

Reproduction Fertility and Development ◽

10.1071/rdv24n1ab238 ◽

2012 ◽

Vol 24 (1) ◽

pp. 231 ◽

Cited By ~ 2

Author(s):

N. Klymiuk ◽

C. Thirion ◽

K. Burkhardt ◽

A. Wuensch ◽

S. Krause ◽

...

Keyword(s):

Duchenne Muscular Dystrophy ◽

Muscular Dystrophy ◽

Nuclear Transfer ◽

Muscle Disease ◽

Pig Model ◽

Mdx Mouse ◽

Cell Clones ◽

Fatty Replacement ◽

Dmd Gene ◽

Dystrophin Protein

Duchenne muscular dystrophy (DMD) is one of the most common genetic diseases in humans, affecting 1 in 3500 boys. It is characterised by progressive muscle weakness and wasting due to mutations in the dystrophin (DMD) gene resulting in absence of dystrophin protein in skeletal muscle. Although curative treatments are currently not available, genetic and pharmacological approaches are under investigation including early-phase clinical trials. Existing animal models in different species (e.g. mdx mouse, GRMD dog) have been instrumental to understand the pathophysiology of DMD, but have several limitations. Importantly, the causative point mutations (mdx mouse: nonsense mutation; GRMD dog: splice mutation) are different from the most common human mutations (out-of-frame deletion of one or several exons of the DMD gene). We used gene targeting in somatic cells and nuclear transfer to generate a genetically tailored pig model of DMD. A bacterial artificial chromosome (BAC) from the porcine DMD gene was modified by recombineering to replace exon 52, resulting in a frame shift in the transcript. Modified BAC were transfected into male neonatal kidney cells, which were screened by quantitative polymerase chain reaction for replacement of exon 52 in the X-linked DMD gene. Eight of 436 cell clones were successfully targeted and 2 of them were used for nuclear transfer. For each of the cell clones, a pregnancy was established by transfer of cloned embryos into recipient gilts. Four piglets of the first litter were live born and killed within 48 h and tissue samples were processed for histological characterisation. Two piglets of the second litter died during birth due to obstetric complications, whereas the other 2 piglets were delivered by Caesarean section and raised in an artificial feeding system. Their serum creatine kinase (CK) levels were grossly elevated. Although both piglets showed reduced mobility compared with age-matched controls, they were able to move and feed on their own. Immunofluorescence staining of dystrophin was negative in muscle fibres of DMD mutant piglets and the complete absence of dystrophin protein was confirmed by immunoblot analysis. Histological examination of biceps femoris muscle from DMD mutant pigs showed a degenerative myopathy with fibre size variation, rounded fibres, central nuclei, fibrosis and fatty replacement of muscle tissue mimicking the hallmarks of the human disease. In conclusion, we generated the first pig model for a genetic muscle disease. The DMD mutant pig appears to be a bona fide model of the human dystrophy as ascertained by absence of the dystrophin protein, elevated serum CK levels and early degenerative changes on muscle histology. Because deletion of exon 52 is one of the most frequent mutations found in human DMD, the exon 52 mutated DMD pig represents an excellent model for testing targeted genetic treatments. This study was supported by the Bayerische Forschungsstiftung.

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Follow-up of three patients with a large in-frame deletion of exons 45–55 in the Duchenne muscular dystrophy (DMD) gene

Journal of Clinical Neuroscience ◽

10.1016/j.jocn.2006.12.012 ◽

2008 ◽

Vol 15 (7) ◽

pp. 757-763 ◽

Cited By ~ 49

Author(s):

Akinori Nakamura ◽

Kunihiro Yoshida ◽

Kazuhiro Fukushima ◽

Hideho Ueda ◽

Nobuyuki Urasawa ◽

...

Keyword(s):

Duchenne Muscular Dystrophy ◽

Muscular Dystrophy ◽

Dmd Gene

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Exon skipping induced by nonsense/frameshift mutations in DMD gene results in Becker muscular dystrophy

Human Genetics ◽

10.1007/s00439-019-02107-4 ◽

2020 ◽

Vol 139 (2) ◽

pp. 247-255 ◽

Cited By ~ 2

Author(s):

Mariko Okubo ◽

Satoru Noguchi ◽

Shinichiro Hayashi ◽

Harumasa Nakamura ◽

Hirofumi Komaki ◽

...

Keyword(s):

Duchenne Muscular Dystrophy ◽

Muscular Dystrophy ◽

Nonsense Mutation ◽

Frameshift Mutation ◽

Exon Skipping ◽

Becker Muscular Dystrophy ◽

Intronic Sequence ◽

Frameshift Mutations ◽

Dmd Gene ◽

Accurate Quantification

AbstractDuchenne muscular dystrophy (DMD) is caused by a nonsense or frameshift mutation in the DMD gene, while its milder form, Becker muscular dystrophy (BMD) is caused by an in-frame deletion/duplication or a missense mutation. Interestingly, however, some patients with a nonsense mutation exhibit BMD phenotype, which is mostly attributed to the skipping of the exon containing the nonsense mutation, resulting in in-frame deletion. This study aims to find BMD cases with nonsense/frameshift mutations in DMD and to investigate the exon skipping rate of those nonsense/frameshift mutations. We searched for BMD cases with nonsense/frameshift mutations in DMD in the Japanese Registry of Muscular Dystrophy. For each DMD mutation identified, we constructed minigene plasmids containing one exon with/without a mutation and its flanking intronic sequence. We then introduced them into HeLa cells and measured the skipping rate of transcripts of the minigene by RT-qPCR. We found 363 cases with a nonsense/frameshift mutation in DMD gene from a total of 1497 dystrophinopathy cases in the registry. Among them, 14 had BMD phenotype. Exon skipping rates were well correlated with presence or absence of dystrophin, suggesting that 5% exon skipping rate is critical for the presence of dystrophin in the sarcolemma, leading to milder phenotypes. Accurate quantification of the skipping rate is important in understanding the exact functions of the nonsense/frameshift mutations in DMD and for interpreting the phenotypes of the BMD patients.

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Comparison of Long-term Ambulatory Function in Patients with Duchenne Muscular Dystrophy Treated with Eteplirsen and Matched Natural History Controls

Journal of Neuromuscular Diseases ◽

10.3233/jnd-200548 ◽

2021 ◽

pp. 1-11

Author(s):

Jerry R. Mendell ◽

Navid Khan ◽

Nanshi Sha ◽

Helen Eliopoulos ◽

Craig M. McDonald ◽

...

Keyword(s):

Duchenne Muscular Dystrophy ◽

Muscular Dystrophy ◽

Gene Mutations ◽

Exon Skipping ◽

Term Treatment ◽

Long Term Treatment ◽

The Difference ◽

Dmd Gene ◽

6 Minute Walk Test

Background: Duchenne muscular dystrophy (DMD) is a rare, X-linked, fatal, degenerative neuromuscular disease caused by DMD gene mutations. A relationship between exon skipping and dystrophin production in exon 51-amenable patients treated with eteplirsen (EXONDYS 51 ®) is established. Once-weekly eteplirsen significantly increased dystrophin, with slower decline in ambulatory function compared to baseline. Long-term treatment with eteplirsen leads to accumulation of dystrophin over time and observed functional benefits in patients with DMD. Objective: Compare long-term ambulatory function in eteplirsen-treated patients versus controls. Methods: Study 201/202 included 12 eteplirsen-treated patients assessed twice/year for ambulatory function over 4 years. Ambulatory evaluations (6-minute walk test [6MWT], loss of ambulation, and North Star Ambulatory Assessment [NSAA]) were compared with matched controls from Italian Telethon and Leuven registries. Results: At Years 3 and 4, eteplirsen-treated patients demonstrated markedly greater mean 6MWT than controls (difference in change from baseline of 132 m [95%CI (29, 235), p = 0.015] at Year 3 and 159 m [95%CI (66, 253), p = 0.002] at Year 4). At Year 4, a significantly greater proportion of eteplirsen-treated patients were still ambulant versus controls (10/12 vs 3/11; p = 0.020). At Year 3, eteplirsen-treated patients had milder NSAA decline than controls (difference in change from baseline of 2.6, 95%CI [-6, 11]), however, the difference was not statistically significant; Year 4 control NSAA data were not available. Conclusion: In this retrospective matched control study, eteplirsen treatment resulted in attenuation of ambulatory decline over a 4-year observation period, supporting long-term benefit in patients with DMD.

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Characterisation of dystrophin during development of human skeletal muscle

Development ◽

10.1242/dev.114.2.395 ◽

1992 ◽

Vol 114 (2) ◽

pp. 395-402 ◽

Cited By ~ 5

Author(s):

A. Clerk ◽

P.N. Strong ◽

C.A. Sewry

Keyword(s):

Skeletal Muscle ◽

Duchenne Muscular Dystrophy ◽

Muscular Dystrophy ◽

Human Skeletal Muscle ◽

Gradual Increase ◽

Differential Staining ◽

Relative Molecular Mass ◽

Adult Tissue ◽

Dmd Gene

Dystrophin, the 427 × 10(3) Mr product of the Duchenne muscular dystrophy (DMD) gene, was studied in human foetal skeletal muscle from 9 to 26 weeks of gestation. Dystrophin could be detected from at least 9 weeks of gestation at the sarcolemmal membrane of most myotubes, though there was differential staining with antibodies raised to various regions of the protein. Dystrophin immunostaining increased and became more uniform with age and by 26 weeks of gestation there was intense sarcolemmal staining of all myotubes. On a Western blot, a doublet of smaller relative molecular mass than that seen in adult tissue was detected in all foetuses studied. There was a gradual increase in abundance of the upper band from 9 to 26 weeks, and the lower band, although present in low amounts in young foetuses, increased significantly between 20 and 26 weeks of gestation. These data indicate that there are several specific isoforms of dystrophin present in developing skeletal muscle, though the role of these is unknown.

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A clinical case of severe Duchenne muscular dystrophy caused by a nonsense mutation in the DMD gene in a girl

L.O. Badalyan Neurological Journal ◽

10.46563/2686-8997-2021-2-4-227-232 ◽

2021 ◽

Vol 2 (4) ◽

pp. 227-232

Author(s):

Tatyana V. Podkletnova ◽

Olga B. Kondakova ◽

Eugeniya V. Uvakina ◽

Dariya A. Fisenko ◽

Anastasiya A. Lyalina ◽

...

Keyword(s):

Duchenne Muscular Dystrophy ◽

Muscular Dystrophy ◽

X Chromosome ◽

Clinical Symptoms ◽

Chromosomal Rearrangements ◽

Clinical Manifestations ◽

Severe Form ◽

Rapid Progression ◽

Compound Heterozygous ◽

Dmd Gene

Duchenne muscular dystrophy (DMD) is a hereditary progressive muscular dystrophy, mainly manifested in boys, is characterized by the onset at an early age, gradual symmetrical atrophy of the striated musculature of the limbs, trunk, as well as damage to the heart muscle. As a rule, girls and women inheriting a pathological mutation are classified only as its carriers and do not have clinical manifestations of the disease. Rare cases when women or girls show clinical manifestations of DMD may be due to chromosomal rearrangements involving the region of the short arm of the X chromosome (Xp21.2), deletions of this region, complete loss of the X chromosome (Shereshevsky-Turner syndrome), homogenous X chromosome dysomnia, compound heterozygous state for two pathogenic mutations in the DMD gene, nonequilibrium inactivation of the X chromosome. When female mutation carriers have DMD clinical symptoms, they usually manifest much milder than boys and young males. Descriptions of patients with the severe course and rapid progression of the disease, comparable in the rate of progression with boys, are rare. In this article, the authors share their experience of observing a girl patient who suffered from a severe form of DMD.

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