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Yavaş C, Doğan M, Eröz R, Türegün K. A rare TNNT1 gene variant causing creatine kinase elevation in nemaline myopathy: c.271_273del (p.Lys91del). Genes Genomics 2024; 46:613-620. [PMID: 38363456 DOI: 10.1007/s13258-024-01502-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2023] [Accepted: 02/01/2024] [Indexed: 02/17/2024]
Abstract
BACKGROUND Nemaline Myopathy (NM) is a rare genetic disorder that affects muscle function and is characterized by the presence of nemaline rods in muscle fibers. These rods are abnormal structures that interfere with muscle contraction and can cause muscle weakness, respiratory distress, and other complications. NM is caused by variants in several genes, including TNNT1, which encodes the protein troponin T1. NM is inherited in an autosomal recessive pattern. The prevalence of heterozygous TNNT1 variants has been reported to be 1/152,000, indicating that the disease is relatively rare. OBJECTIVE Investigation of TNNT1 gene variants that may cause cretin kinase elevation. METHODS Detailed family histories and clinical data were recorded. Whole exome sequencing was performed and family segregation was done by Sanger sequencing. RESULTS In this study, we report a 5-year-old girl with a novel variant recessive congenital TNNT1 myopathy. The patient had a novel homozygous (c.271_273del) deletion in the TNNT1 gene that is associated with creatine kinase elevation, which is a marker of muscle damage. CONCLUSION This case expands the phenotypic spectrum of TNNT1 myopathy and highlights the importance of genetic testing and counseling for families affected by this rare disorder. In this study provides valuable insights into the genetic basis of NM and highlights the importance of early diagnosis and management for patients with this rare disorder. Further research is needed to better understand the pathophysiology of TNNT1 myopathy and to develop effective treatments for this debilitating condition.
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Affiliation(s)
- Cüneyd Yavaş
- Department of Molecular Biology and Genetics, Biruni University, Karanfil St. No:1H/12, Beylikduzu, Istanbul, 34100, Turkey.
| | - Mustafa Doğan
- Genetic Diseases Assessment Center, Basaksehir Cam and Sakura City Hospital, Istanbul, Turkey
| | - Recep Eröz
- Department of Medical Genetics Medical Faculty, Aksaray University, Aksaray, Turkey
| | - Kübra Türegün
- Department of Biotechnology, Institute of Science and Technology, Yıldız Technical University, Istanbul, Turkey
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Strauss KA, Carson VJ, Bolettieri E, Everett M, Bollinger A, Bowser LE, Beiler K, Young M, Edvardson S, Fraenkel N, D'Amico A, Bertini E, Lingappa L, Chowdhury D, Lowes LP, Iammarino M, Alfano LN, Brigatti KW. WiTNNess: An international natural history study of infantile-onset TNNT1 myopathy. Ann Clin Transl Neurol 2023; 10:1972-1984. [PMID: 37632133 PMCID: PMC10647004 DOI: 10.1002/acn3.51884] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2023] [Revised: 07/10/2023] [Accepted: 08/02/2023] [Indexed: 08/27/2023] Open
Abstract
OBJECTIVE We created WiTNNess as a hybrid prospective/cross-sectional observational study to simulate a clinical trial for infantile-onset TNNT1 myopathy. Our aims were to identify populations for future trial enrollment, rehearse outcome assessments, specify endpoints, and refine trial logistics. METHODS Eligible participants had biallelic pathogenic variants of TNNT1 and infantile-onset proximal weakness without confounding conditions. The primary endpoint was ventilator-free survival. "Thriving" was a secondary endpoint defined as the ability to swallow and grow normally without non-oral feeding support. Endpoints of gross motor function included independent sitting and standing as defined by the Word Health Organization, a novel TNNT1 abbreviated motor score, and video mapping of limb movement. We recorded adverse events, concomitant medications, and indices of organ function to serve as comparators of safety in future trials. RESULTS Sixteen children were enrolled in the aggregate cohort (6 prospective, 10 cross-sectional; median census age 2.3 years, range 0.5-13.8). Median ventilator-free survival was 20.2 months and probability of death or permanent mechanical ventilation was 100% by age 60 months. All six children (100%) in the prospective arm failed to thrive by age 12 months. Only 2 of 16 (13%) children in the aggregate cohort sat independently and none stood alone. Novel exploratory motor assessments also proved informative. Laboratory and imaging data suggest that primary manifestations of TNNT1 deficiency are restricted to skeletal muscle. INTERPRETATION WiTNNess allowed us to streamline and economize the collection of historical control data without compromising scientific rigor, and thereby establish a sound operational framework for future clinical trials.
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Affiliation(s)
- Kevin A. Strauss
- Clinic for Special ChildrenStrasburgPennsylvaniaUSA
- Department of PediatricsPenn Medicine‐Lancaster General HospitalPennsylvaniaLancasterUSA
- Department of PediatricsUMass Chan Medical SchoolWorcesterMassachusettsUSA
- Department of Molecular, Cell & Cancer BiologyUMass Chan Medical SchoolWorcesterMassachusettsUSA
| | - Vincent J. Carson
- Clinic for Special ChildrenStrasburgPennsylvaniaUSA
- Department of PediatricsPenn Medicine‐Lancaster General HospitalPennsylvaniaLancasterUSA
| | | | | | | | | | | | - Millie Young
- Clinic for Special ChildrenStrasburgPennsylvaniaUSA
| | - Simon Edvardson
- ALYN Hospital Pediatric and Adolescent Rehabilitation CenterJerusalemIsrael
| | - Nitay Fraenkel
- ALYN Hospital Pediatric and Adolescent Rehabilitation CenterJerusalemIsrael
| | - Adele D'Amico
- Unit of Muscular and Neurodegenerative Disorders, Department of NeurosciencesIRCCS Bambino Gesù Children's HospitalRomeItaly
| | - Enrico Bertini
- Unit of Muscular and Neurodegenerative Disorders, Department of NeurosciencesIRCCS Bambino Gesù Children's HospitalRomeItaly
| | - Lokesh Lingappa
- Department of Pediatric NeurologyRainbow Children's HospitalHyderabadIndia
| | - Devyani Chowdhury
- Cardiology Care for ChildrenLancasterPennsylvaniaUSA
- Department of CardiologyNemours Children's HealthWilmingtonDelawareUSA
| | - Linda P. Lowes
- Center for Gene TherapyNationwide Children's HospitalColumbusOhioUSA
| | - Megan Iammarino
- Center for Gene TherapyNationwide Children's HospitalColumbusOhioUSA
| | - Lindsay N. Alfano
- Center for Gene TherapyNationwide Children's HospitalColumbusOhioUSA
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Exon skipping caused by splicing mutation in TNNT1 nemaline myopathy. J Hum Genet 2023; 68:97-101. [PMID: 36446828 DOI: 10.1038/s10038-022-01096-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2022] [Revised: 11/17/2022] [Accepted: 11/17/2022] [Indexed: 11/30/2022]
Abstract
The TNNT1 gene encoding the slow skeletal muscle TnT has been identified as a causative gene for nemaline myopathy. TNNT1 nemaline myopathy is mainly characterized by neonatal-onset muscle weakness, pectus carinatum and respiratory insufficiency. Herein, we report on a Chinese girl with TNNT1 nemaline myopathy with mild clinical phenotypes without thoracic deformities or decreased respiratory function. Muscle biopsy showed moderate to marked type 1 fiber atrophy and nemaline rods. Next-generation sequencing identified the compound heterozygous c. 587dupA (p. D196Efs*41) and c. 387+5G>A mutations in the TNNT1 gene according to the transcript NM_003283.4. RNA sequencing revealed complete exon 9 skipping caused by the c. 387+5G>A mutation. Through quantitative PCR, we found that both the truncation c. 587dupA (p. D196Efs*41) and the splicing c. 387+5G>A mutations triggered nonsense-mediated mRNA decay (NMD). Western blotting showed the residual amount of the truncated TNNT1 protein by deletion of exon 9, which may ameliorate the disease to some extent.
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Wang S, Tian W, Pan D, Liu L, Xu C, Ma Y, Wang D, Jiang L. A Comprehensive Analysis of the Myocardial Transcriptome in ZBED6-Knockout Bama Xiang Pigs. Genes (Basel) 2022; 13:genes13081382. [PMID: 36011293 PMCID: PMC9407500 DOI: 10.3390/genes13081382] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2022] [Revised: 07/28/2022] [Accepted: 07/29/2022] [Indexed: 02/04/2023] Open
Abstract
The ZBED6 gene is a transcription factor that regulates the expression of IGF2 and affects muscle growth and development. However, its effect on the growth and development of the heart is still unknown. Emerging evidence suggests that long noncoding RNAs (lncRNAs) can regulate genes at the epigenetic, transcriptional, and posttranscriptional levels and play an important role in the development of eukaryotes. To investigate the function of ZBED6 in the cardiac development of pigs, we constructed the expression profiles of mRNAs and lncRNAs in myocardial tissue obtained from Bama Xiang pigs in the ZBED6 knockout group (ZBED6-KO) and the wild-type group (ZBED6-WT). A total of 248 differentially expressed genes (DEGs) and 209 differentially expressed lncRNAs (DELs) were detected, and 105 potential cis target genes of DELs were identified. The functional annotation analysis based on the Gene Ontology (GO) and Kyoto Encyclopaedia of Genes and Genomes (KEGG) databases revealed two GO items related to muscle development by the cis target genes of DELs. Moreover, IGF2 was the direct target gene of ZBED6 by ChIP-PCR experiment. Our results explored the mechanism and expression profile of mRNAs and lncRNAs of ZBED6 gene knockout on myocardium tissue development, mining the key candidate genes in that process like IGF2.
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Affiliation(s)
- Shengnan Wang
- Laboratory of Animal (Poultry) Genetics Breeding and Reproduction, Ministry of Agriculture, Institute of Animal Science, Chinese Academy of Agricultural Sciences (CAAS), Beijing 100193, China; (S.W.); (C.X.); (Y.M.)
- National Germplasm Center of Domestic Animal Resources, Ministry of Science and Technology of the People’s Republic of China, Institute of Animal Science, Chinese Academy of Agricultural Sciences (CAAS), Beijing 100193, China; (W.T.); (L.L.)
| | - Wenjie Tian
- National Germplasm Center of Domestic Animal Resources, Ministry of Science and Technology of the People’s Republic of China, Institute of Animal Science, Chinese Academy of Agricultural Sciences (CAAS), Beijing 100193, China; (W.T.); (L.L.)
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, College of Animal Science and Technology, Guangxi University, Nanning 530004, China
| | - Dengke Pan
- Institute of Organ Transplantation, Sichuan Academy of Medical Sciences & Sichuan Provincial People’s Hospital, Chengdu 610072, China;
| | - Ling Liu
- National Germplasm Center of Domestic Animal Resources, Ministry of Science and Technology of the People’s Republic of China, Institute of Animal Science, Chinese Academy of Agricultural Sciences (CAAS), Beijing 100193, China; (W.T.); (L.L.)
- College of Animal Science and Technology, Qingdao Agricultural University, Qingdao 266109, China
| | - Cheng Xu
- Laboratory of Animal (Poultry) Genetics Breeding and Reproduction, Ministry of Agriculture, Institute of Animal Science, Chinese Academy of Agricultural Sciences (CAAS), Beijing 100193, China; (S.W.); (C.X.); (Y.M.)
- National Germplasm Center of Domestic Animal Resources, Ministry of Science and Technology of the People’s Republic of China, Institute of Animal Science, Chinese Academy of Agricultural Sciences (CAAS), Beijing 100193, China; (W.T.); (L.L.)
| | - Yuehui Ma
- Laboratory of Animal (Poultry) Genetics Breeding and Reproduction, Ministry of Agriculture, Institute of Animal Science, Chinese Academy of Agricultural Sciences (CAAS), Beijing 100193, China; (S.W.); (C.X.); (Y.M.)
- National Germplasm Center of Domestic Animal Resources, Ministry of Science and Technology of the People’s Republic of China, Institute of Animal Science, Chinese Academy of Agricultural Sciences (CAAS), Beijing 100193, China; (W.T.); (L.L.)
| | - Dandan Wang
- Laboratory of Animal (Poultry) Genetics Breeding and Reproduction, Ministry of Agriculture, Institute of Animal Science, Chinese Academy of Agricultural Sciences (CAAS), Beijing 100193, China; (S.W.); (C.X.); (Y.M.)
- Correspondence: (D.W.); (L.J.)
| | - Lin Jiang
- National Germplasm Center of Domestic Animal Resources, Ministry of Science and Technology of the People’s Republic of China, Institute of Animal Science, Chinese Academy of Agricultural Sciences (CAAS), Beijing 100193, China; (W.T.); (L.L.)
- Correspondence: (D.W.); (L.J.)
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Holling T, Lisfeld J, Johannsen J, Matschke J, Song F, Altmeppen HC, Kutsche K. Autosomal dominantly inherited myopathy likely caused by the TNNT1 variant p.(Asp65Ala). Hum Mutat 2022; 43:1224-1233. [PMID: 35510366 DOI: 10.1002/humu.24397] [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: 09/24/2021] [Revised: 04/25/2022] [Accepted: 05/01/2022] [Indexed: 11/12/2022]
Abstract
Nemaline myopathies (NEM) are genetically and clinically heterogenous. Biallelic or monoallelic variants in TNNT1, encoding slow skeletal troponin T1 (TnT1), cause NEM. We report a 2-year-old patient and his mother carrying the heterozygous TNNT1 variant c.194A>C/p.(Asp65Ala) that occurred de novo in the mother. Both had muscle hypotrophy and muscle weakness. Muscle pathology in the proband's mother revealed slow twitch type 1 fiber hypotrophy and fast twitch type 2 fiber hypertrophy that was confirmed by a reduced ratio of slow skeletal myosin to fast skeletal myosin type 2a. RT-PCR and immunoblotting data demonstrated increased levels of high-molecular-weight TnT1 isoforms in skeletal muscle of the proband's mother that were also observed in some controls. In an overexpression system, complex formation of TnT1-D65A with tropomyosin 3 (TPM3) was enhanced. The previously reported TnT1-E104V and TnT1-L96P mutants showed reduced or no co-immunoprecipitation with TPM3. Our studies support pathogenicity of the TNNT1 p.(Asp65Ala) variant. This article is protected by copyright. All rights reserved.
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Affiliation(s)
- Tess Holling
- Institute of Human Genetics, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Jasmin Lisfeld
- Institute of Human Genetics, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Jessika Johannsen
- Children's Hospital, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Jakob Matschke
- Institute of Neuropathology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Feizhi Song
- Institute of Neuropathology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | | | - Kerstin Kutsche
- Institute of Human Genetics, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
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Zambon AA, Abel F, Linnane B, O'Rourke D, Phadke R, Sewry CA, Sarkozy A, Manzur A, Muntoni F. Troponin-T type 1 (TNNT1)-related nemaline myopathy: unique respiratory phenotype and muscle pathology findings. Neuromuscul Disord 2022; 32:245-254. [DOI: 10.1016/j.nmd.2022.01.014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2021] [Revised: 01/26/2022] [Accepted: 01/27/2022] [Indexed: 10/19/2022]
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TNNT1 myopathy with novel compound heterozygous mutations. Neuromuscul Disord 2021; 32:176-184. [DOI: 10.1016/j.nmd.2021.12.003] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2021] [Revised: 12/07/2021] [Accepted: 12/10/2021] [Indexed: 01/10/2023]
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8
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De La Vega FM, Chowdhury S, Moore B, Frise E, McCarthy J, Hernandez EJ, Wong T, James K, Guidugli L, Agrawal PB, Genetti CA, Brownstein CA, Beggs AH, Löscher BS, Franke A, Boone B, Levy SE, Õunap K, Pajusalu S, Huentelman M, Ramsey K, Naymik M, Narayanan V, Veeraraghavan N, Billings P, Reese MG, Yandell M, Kingsmore SF. Artificial intelligence enables comprehensive genome interpretation and nomination of candidate diagnoses for rare genetic diseases. Genome Med 2021; 13:153. [PMID: 34645491 PMCID: PMC8515723 DOI: 10.1186/s13073-021-00965-0] [Citation(s) in RCA: 51] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2021] [Accepted: 08/27/2021] [Indexed: 01/08/2023] Open
Abstract
BACKGROUND Clinical interpretation of genetic variants in the context of the patient's phenotype is becoming the largest component of cost and time expenditure for genome-based diagnosis of rare genetic diseases. Artificial intelligence (AI) holds promise to greatly simplify and speed genome interpretation by integrating predictive methods with the growing knowledge of genetic disease. Here we assess the diagnostic performance of Fabric GEM, a new, AI-based, clinical decision support tool for expediting genome interpretation. METHODS We benchmarked GEM in a retrospective cohort of 119 probands, mostly NICU infants, diagnosed with rare genetic diseases, who received whole-genome or whole-exome sequencing (WGS, WES). We replicated our analyses in a separate cohort of 60 cases collected from five academic medical centers. For comparison, we also analyzed these cases with current state-of-the-art variant prioritization tools. Included in the comparisons were trio, duo, and singleton cases. Variants underpinning diagnoses spanned diverse modes of inheritance and types, including structural variants (SVs). Patient phenotypes were extracted from clinical notes by two means: manually and using an automated clinical natural language processing (CNLP) tool. Finally, 14 previously unsolved cases were reanalyzed. RESULTS GEM ranked over 90% of the causal genes among the top or second candidate and prioritized for review a median of 3 candidate genes per case, using either manually curated or CNLP-derived phenotype descriptions. Ranking of trios and duos was unchanged when analyzed as singletons. In 17 of 20 cases with diagnostic SVs, GEM identified the causal SVs as the top candidate and in 19/20 within the top five, irrespective of whether SV calls were provided or inferred ab initio by GEM using its own internal SV detection algorithm. GEM showed similar performance in absence of parental genotypes. Analysis of 14 previously unsolved cases resulted in a novel finding for one case, candidates ultimately not advanced upon manual review for 3 cases, and no new findings for 10 cases. CONCLUSIONS GEM enabled diagnostic interpretation inclusive of all variant types through automated nomination of a very short list of candidate genes and disorders for final review and reporting. In combination with deep phenotyping by CNLP, GEM enables substantial automation of genetic disease diagnosis, potentially decreasing cost and expediting case review.
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Affiliation(s)
- Francisco M. De La Vega
- Fabric Genomics Inc., Oakland, CA USA
- Department of Biomedical Data Science, Stanford University School of Medicine, Stanford, CA USA
- Current Address: Tempus Labs Inc., Redwood City, CA 94065 USA
| | - Shimul Chowdhury
- Rady Children’s Institute for Genomic Medicine, San Diego, CA USA
| | - Barry Moore
- Department of Human Genetics, Utah Center for Genetic Discovery, University of Utah, Salt Lake City, UT USA
| | | | | | - Edgar Javier Hernandez
- Department of Human Genetics, Utah Center for Genetic Discovery, University of Utah, Salt Lake City, UT USA
| | - Terence Wong
- Rady Children’s Institute for Genomic Medicine, San Diego, CA USA
| | - Kiely James
- Rady Children’s Institute for Genomic Medicine, San Diego, CA USA
| | - Lucia Guidugli
- Rady Children’s Institute for Genomic Medicine, San Diego, CA USA
| | - Pankaj B. Agrawal
- Division of Genetics and Genomics, The Manton Center for Orphan Disease Research, Boston Children’s Hospital, Harvard Medical School, Boston, MA USA
- Division of Newborn Medicine, Boston Children’s Hospital, Boston, MA USA
| | - Casie A. Genetti
- Division of Genetics and Genomics, The Manton Center for Orphan Disease Research, Boston Children’s Hospital, Harvard Medical School, Boston, MA USA
| | - Catherine A. Brownstein
- Division of Genetics and Genomics, The Manton Center for Orphan Disease Research, Boston Children’s Hospital, Harvard Medical School, Boston, MA USA
| | - Alan H. Beggs
- Division of Genetics and Genomics, The Manton Center for Orphan Disease Research, Boston Children’s Hospital, Harvard Medical School, Boston, MA USA
| | - Britt-Sabina Löscher
- Institute of Clinical Molecular Biology, Christian-Albrechts-University of Kiel & University Hospital Schleswig-Holstein, Kiel, Germany
| | - Andre Franke
- Institute of Clinical Molecular Biology, Christian-Albrechts-University of Kiel & University Hospital Schleswig-Holstein, Kiel, Germany
| | - Braden Boone
- HudsonAlpha Institute for Biotechnology, Huntsville, AL USA
| | - Shawn E. Levy
- HudsonAlpha Institute for Biotechnology, Huntsville, AL USA
| | - Katrin Õunap
- Department of Clinical Genetics, United Laboratories, Tartu University Hospital, Tartu, Estonia
- Department of Clinical Genetics, Institute of Clinical Medicine, University of Tartu, Tartu, Estonia
| | - Sander Pajusalu
- Department of Clinical Genetics, United Laboratories, Tartu University Hospital, Tartu, Estonia
- Department of Clinical Genetics, Institute of Clinical Medicine, University of Tartu, Tartu, Estonia
| | - Matt Huentelman
- Center for Rare Childhood Disorders, Translational Genomics Research Institute, Phoenix, AZ USA
| | - Keri Ramsey
- Center for Rare Childhood Disorders, Translational Genomics Research Institute, Phoenix, AZ USA
| | - Marcus Naymik
- Center for Rare Childhood Disorders, Translational Genomics Research Institute, Phoenix, AZ USA
| | - Vinodh Narayanan
- Center for Rare Childhood Disorders, Translational Genomics Research Institute, Phoenix, AZ USA
| | | | | | | | - Mark Yandell
- Fabric Genomics Inc., Oakland, CA USA
- Department of Human Genetics, Utah Center for Genetic Discovery, University of Utah, Salt Lake City, UT USA
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Ogasawara M, Nishino I. A review of core myopathy: central core disease, multiminicore disease, dusty core disease, and core-rod myopathy. Neuromuscul Disord 2021; 31:968-977. [PMID: 34627702 DOI: 10.1016/j.nmd.2021.08.015] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2021] [Revised: 08/13/2021] [Accepted: 08/16/2021] [Indexed: 12/21/2022]
Abstract
Core myopathies are clinically, pathologically, and genetically heterogeneous muscle diseases. Their onset and clinical severity are variable. Core myopathies are diagnosed by muscle biopsy showing focally reduced oxidative enzyme activity and can be pathologically divided into central core disease, multiminicore disease, dusty core disease, and core-rod myopathy. Although RYR1-related myopathy is the most common core myopathy, an increasing number of other causative genes have been reported, including SELENON, MYH2, MYH7, TTN, CCDC78, UNC45B, ACTN2, MEGF10, CFL2, KBTBD13, and TRIP4. Furthermore, the genes originally reported to cause nemaline myopathy, namely ACTA1, NEB, and TNNT1, have been recently associated with core-rod myopathy. Genetic analysis allows us to diagnose each core myopathy more accurately. In this review, we aim to provide up-to-date information about core myopathies.
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Affiliation(s)
- Masashi Ogasawara
- Department of Neuromuscular Research, National Center of Neurology and Psychiatry (NCNP), National Institute of Neuroscience, 4-1-1 Ogawahigashi, Tokyo 187-8502, Japan; Medical Genome Center, NCNP, Tokyo, Kodaira, Japan; Department of Pediatrics, Showa General Hospital, Tokyo, Kodaira, Japan
| | - Ichizo Nishino
- Department of Neuromuscular Research, National Center of Neurology and Psychiatry (NCNP), National Institute of Neuroscience, 4-1-1 Ogawahigashi, Tokyo 187-8502, Japan; Medical Genome Center, NCNP, Tokyo, Kodaira, Japan.
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10
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Laitila J, Wallgren-Pettersson C. Recent advances in nemaline myopathy. Neuromuscul Disord 2021; 31:955-967. [PMID: 34561123 DOI: 10.1016/j.nmd.2021.07.012] [Citation(s) in RCA: 37] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2021] [Revised: 07/14/2021] [Accepted: 07/16/2021] [Indexed: 11/18/2022]
Abstract
The nemaline myopathies constitute a large proportion of the congenital or structural myopathies. Common to all patients is muscle weakness and the presence in the muscle biopsy of nemaline rods. The causative genes are at least twelve, encoding structural or regulatory proteins of the thin filament, and the clinical picture as well as the histological appearance on muscle biopsy vary widely. Here, we suggest a renewed clinical classification to replace the original one, summarise what is known about the pathogenesis from mutations in each causative gene to the forms of nemaline myopathy described to date, and provide perspectives on pathogenetic mechanisms possibly open to therapeutic modalities.
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Affiliation(s)
- Jenni Laitila
- The Folkhälsan Institute of Genetics, Folkhälsan Research Center, Helsinki, Finland; Department of Medical Genetics, Medicum, University of Helsinki, Finland; Department of Biomedical Sciences, University of Copenhagen, Denmark.
| | - Carina Wallgren-Pettersson
- The Folkhälsan Institute of Genetics, Folkhälsan Research Center, Helsinki, Finland; Department of Medical Genetics, Medicum, University of Helsinki, Finland
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van de Locht M, Borsboom TC, Winter JM, Ottenheijm CAC. Troponin Variants in Congenital Myopathies: How They Affect Skeletal Muscle Mechanics. Int J Mol Sci 2021; 22:ijms22179187. [PMID: 34502093 PMCID: PMC8430961 DOI: 10.3390/ijms22179187] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2021] [Revised: 08/19/2021] [Accepted: 08/23/2021] [Indexed: 02/05/2023] Open
Abstract
The troponin complex is a key regulator of muscle contraction. Multiple variants in skeletal troponin encoding genes result in congenital myopathies. TNNC2 has been implicated in a novel congenital myopathy, TNNI2 and TNNT3 in distal arthrogryposis (DA), and TNNT1 and TNNT3 in nemaline myopathy (NEM). Variants in skeletal troponin encoding genes compromise sarcomere function, e.g., by altering the Ca2+ sensitivity of force or by inducing atrophy. Several potential therapeutic strategies are available to counter the effects of variants, such as troponin activators, introduction of wild-type protein through AAV gene therapy, and myosin modulation to improve muscle contraction. The mechanisms underlying the pathophysiological effects of the variants in skeletal troponin encoding genes are incompletely understood. Furthermore, limited knowledge is available on the structure of skeletal troponin. This review focusses on the physiology of slow and fast skeletal troponin and the pathophysiology of reported variants in skeletal troponin encoding genes. A better understanding of the pathophysiological effects of these variants, together with enhanced knowledge regarding the structure of slow and fast skeletal troponin, will direct the development of treatment strategies.
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Juntas Morales R, Perrin A, Solé G, Lacourt D, Pegeot H, Walther-Louvier U, Cintas P, Cances C, Espil C, Theze C, Zenagui R, Yauy K, Cosset E, Renard D, Rigau V, Maues de Paula A, Uro-Coste E, Arne-Bes MC, Martin Négrier ML, Leboucq N, Acket B, Malfatti E, Biancalana V, Metay C, Richard P, Rendu J, Rivier F, Koenig M, Cossée M. An Integrated Clinical-Biological Approach to Identify Interindividual Variability and Atypical Phenotype-Genotype Correlations in Myopathies: Experience on A Cohort of 156 Families. Genes (Basel) 2021; 12:genes12081199. [PMID: 34440373 PMCID: PMC8392536 DOI: 10.3390/genes12081199] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2021] [Revised: 07/29/2021] [Accepted: 07/30/2021] [Indexed: 01/17/2023] Open
Abstract
Diagnosis of myopathies is challenged by the high genetic heterogeneity and clinical overlap of the various etiologies. We previously reported a Next-Generation Sequencing strategy to identify genetic etiology in patients with undiagnosed Limb-Girdle Muscular Dystrophies, Congenital Myopathies, Congenital Muscular Dystrophies, Distal Myopathies, Myofibrillar Myopathies, and hyperCKemia or effort intolerance, using a large gene panel including genes classically associated with other entry diagnostic categories. In this study, we report the comprehensive clinical-biological strategy used to interpret NGS data in a cohort of 156 pediatric and adult patients, that included Copy Number Variants search, variants filtering and interpretation according to ACMG guidelines, segregation studies, deep phenotyping of patients and relatives, transcripts and protein studies, and multidisciplinary meetings. Genetic etiology was identified in 74 patients, a diagnostic yield (47.4%) similar to previous studies. We identified 18 patients (10%) with causative variants in different genes (ACTA1, RYR1, NEB, TTN, TRIP4, CACNA1S, FLNC, TNNT1, and PAPBN1) that resulted in milder and/or atypical phenotypes, with high intrafamilial variability in some cases. Mild phenotypes could mostly be explained by a less deleterious effect of variants on the protein. Detection of inter-individual variability and atypical phenotype-genotype associations is essential for precision medicine, patient care, and to progress in the understanding of the molecular mechanisms of myopathies.
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Affiliation(s)
- Raul Juntas Morales
- Explorations Neurologiques et Centre SLA, Centre de Référence des Maladies Neuromusculaires AOC (Atlantique-Occitanie-Caraïbe), Centre Hospitalier Universitaire de Montpellier, 34295 Montpellier, France;
- Équipe Accueil EA7402, Institut Universitaire de Recherche Clinique (IURC), Université de Montpellier, 34093 Montpellier, France;
| | - Aurélien Perrin
- Laboratoire de Génétique Moléculaire, Centre Hospitalier Universitaire de Montpellier, 34093 Montpellier, France; (A.P.); (D.L.); (H.P.); (C.T.); (R.Z.); (K.Y.); (M.K.)
- PhyMedExp, Université de Montpellier, INSERM, CNRS, 34093 Montpellier, France
| | - Guilhem Solé
- Service de Neurologie, Centre Hospitalier Universitaire de Bordeaux, Centre de référence des Maladies Neuromusculaires AOC (Atlantique-Occitanie-Caraïbe), 33000 Bordeaux, France;
| | - Delphine Lacourt
- Laboratoire de Génétique Moléculaire, Centre Hospitalier Universitaire de Montpellier, 34093 Montpellier, France; (A.P.); (D.L.); (H.P.); (C.T.); (R.Z.); (K.Y.); (M.K.)
| | - Henri Pegeot
- Laboratoire de Génétique Moléculaire, Centre Hospitalier Universitaire de Montpellier, 34093 Montpellier, France; (A.P.); (D.L.); (H.P.); (C.T.); (R.Z.); (K.Y.); (M.K.)
| | - Ulrike Walther-Louvier
- Service de Neuropédiatrie, Centre Hospitalier Universitaire de Montpellier, Centre de référence des Maladies Neuromusculaires AOC (Atlantique-Occitanie-Caraïbe), 34295 Montpellier, France; (U.W.-L.); (F.R.)
| | - Pascal Cintas
- Service de Neurologie, Centre Hospitalier Universitaire de Toulouse, Centre de référence des Maladies Neuromusculaires AOC (Atlantique-Occitanie-Caraïbe), 31059 Toulouse, France; (P.C.); (M.-C.A.-B.); (B.A.)
| | - Claude Cances
- Service de Neuropédiatrie, Centre Hospitalier Universitaire de Toulouse, Centre de référence des Maladies Neuromusculaires AOC (Atlantique-Occitanie-Caraïbe), 31059 Toulouse, France;
| | - Caroline Espil
- Service de Neuropédiatrie, Centre Hospitalier de Bordeaux, Centre de référence des Maladies Neuromusculaires AOC (Atlantique-Occitanie-Caraïbe), 33000 Bordeaux, France;
| | - Corinne Theze
- Laboratoire de Génétique Moléculaire, Centre Hospitalier Universitaire de Montpellier, 34093 Montpellier, France; (A.P.); (D.L.); (H.P.); (C.T.); (R.Z.); (K.Y.); (M.K.)
| | - Reda Zenagui
- Laboratoire de Génétique Moléculaire, Centre Hospitalier Universitaire de Montpellier, 34093 Montpellier, France; (A.P.); (D.L.); (H.P.); (C.T.); (R.Z.); (K.Y.); (M.K.)
| | - Kevin Yauy
- Laboratoire de Génétique Moléculaire, Centre Hospitalier Universitaire de Montpellier, 34093 Montpellier, France; (A.P.); (D.L.); (H.P.); (C.T.); (R.Z.); (K.Y.); (M.K.)
| | - Elodie Cosset
- Équipe Accueil EA7402, Institut Universitaire de Recherche Clinique (IURC), Université de Montpellier, 34093 Montpellier, France;
| | - Dimitri Renard
- Service de Neurologie, Centre Hospitalier Universitaire de Nîmes, Centre de référence des Maladies Neuromusculaires AOC (Atlantique-Occitanie-Caraïbe), 30029 Nîmes, France;
| | - Valerie Rigau
- Service de Pathologie, Centre Hospitalier Universitaire de Montpellier, Centre de Référence des Maladies Neuromusculaires AOC (Atlantique-Occitanie-Caraïbe), 34295 Montpellier, France;
| | - Andre Maues de Paula
- Service de Pathologie, Centre Hospitalier Universitaire de Marseille, Centre de Référence des Maladies Neuromusculaires PACA-Réunion-Rhône Alpes, 13005 Marseille, France;
| | - Emmanuelle Uro-Coste
- Service de Pathologie, Centre Hospitalier Universitaire de Toulouse, Centre de Référence des Maladies Neuromusculaires AOC (Atlantique-Occitanie-Caraïbe), 31300 Toulouse, France;
| | - Marie-Christine Arne-Bes
- Service de Neurologie, Centre Hospitalier Universitaire de Toulouse, Centre de référence des Maladies Neuromusculaires AOC (Atlantique-Occitanie-Caraïbe), 31059 Toulouse, France; (P.C.); (M.-C.A.-B.); (B.A.)
| | - Marie-Laure Martin Négrier
- CHU de Bordeaux, Institut des Maladies Neurodégénératives, Université de Bordeaux, UMR 5293, 33076 Bordeaux, France;
| | - Nicolas Leboucq
- Service de Neuroradiologie, Centre Hospitalier de Montpellier, Centre de Référence des Maladies Neuromusculaires AOC (Atlantique-Occitanie-Caraïbe), 34295 Montpellier, France;
| | - Blandine Acket
- Service de Neurologie, Centre Hospitalier Universitaire de Toulouse, Centre de référence des Maladies Neuromusculaires AOC (Atlantique-Occitanie-Caraïbe), 31059 Toulouse, France; (P.C.); (M.-C.A.-B.); (B.A.)
| | - Edoardo Malfatti
- Service Neurologie Médicale, Centre de Référence Maladies Neuromusculaires Nord-Est-Ile-de-France, CHU Raymond-Poincaré, 92380 Garches, France;
- U1179 UVSQ-INSERM Handicap Neuromusculaire: Physiologie, Biothérapie et Pharmacologie Appliquées, UFR des Sciences de la Santé Simone Veil, Université Versailles-Saint-Quentin-en-Yvelines, 78180 Versailles, France
| | - Valérie Biancalana
- Laboratoire de Diagnostic Génétique, Université de Strasbourg, 67084 Strasbourg, France;
- Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), Inserm U1258, CNRS UMR7104, Université de Strasbourg, 67404 Illkirch, France
| | - Corinne Metay
- Unité Fonctionnelle de Cardiogénétique et Myogénétique, Centre de Génétique, Hôpitaux Universitaire Pitié Salpêtrière–Charles Foix, 75651 Paris, France; (C.M.); (P.R.)
| | - Pascale Richard
- Unité Fonctionnelle de Cardiogénétique et Myogénétique, Centre de Génétique, Hôpitaux Universitaire Pitié Salpêtrière–Charles Foix, 75651 Paris, France; (C.M.); (P.R.)
| | - John Rendu
- CHU Grenoble, Université de Grenoble Alpes, Inserm, U1216, GIN, 38706 Saint-Martin-d’Hères, France;
- Unité Médicale de Génétique Moléculaire, Centre Hospitalier, Universitaire Grenoble Alpes, 38043 Saint-Martin-d’Hères, France
| | - François Rivier
- Service de Neuropédiatrie, Centre Hospitalier Universitaire de Montpellier, Centre de référence des Maladies Neuromusculaires AOC (Atlantique-Occitanie-Caraïbe), 34295 Montpellier, France; (U.W.-L.); (F.R.)
| | - Michel Koenig
- Laboratoire de Génétique Moléculaire, Centre Hospitalier Universitaire de Montpellier, 34093 Montpellier, France; (A.P.); (D.L.); (H.P.); (C.T.); (R.Z.); (K.Y.); (M.K.)
- PhyMedExp, Université de Montpellier, INSERM, CNRS, 34093 Montpellier, France
| | - Mireille Cossée
- Laboratoire de Génétique Moléculaire, Centre Hospitalier Universitaire de Montpellier, 34093 Montpellier, France; (A.P.); (D.L.); (H.P.); (C.T.); (R.Z.); (K.Y.); (M.K.)
- PhyMedExp, Université de Montpellier, INSERM, CNRS, 34093 Montpellier, France
- Correspondence:
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Abstract
PURPOSE OF REVIEW Tremor is a common neurological symptom with a plethora of potential etiologies. Apart from physiological tremor, the vast majority of tremor syndromes are linked to a pacemaker in the central nervous system (CNS) or, less common, in the peripheral nervous system. Myogenic tremor is a novel tremor entity, first reported in 2019 and believed to originate in the muscle itself. In this review, we describe the clinical properties of myogenic tremor and discuss its presumed pathogenesis on the basis of all of the patient cases published so far. RECENT FINDINGS Myogenic tremor manifests itself as a high frequency, postural, and kinetic tremor with onset in infancy. To date, only myopathies affecting the contractile elements, in particular myosin and a myosin-associated protein, have been recognized to feature myogenic tremor. The generator of the tremor is believed to be located in the sarcomere, with propagation and amplification of sarcomeric oscillatory activity through CNS reflex loops, similar to neuropathic tremor. SUMMARY True myogenic tremor must be distinguished from centrally mediated tremor due to myopathies with central nervous system involvement, i.e., mitochondrial myopathies or myotonic dystrophies. The presence of myogenic tremor strongly points toward a sarcomere-associated mutation and may thus be a valuable clinical tool for the differential diagnosis of myopathies.
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Petrucci A, Primiano G, Savarese M, Sancricca C, Udd B, Servidei S. Novel TNNT1 mutation and mild nemaline myopathy phenotype in an Italian patient. Neuromuscul Disord 2021; 31:532-538. [PMID: 33832840 DOI: 10.1016/j.nmd.2021.03.001] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2020] [Revised: 02/15/2021] [Accepted: 03/01/2021] [Indexed: 12/19/2022]
Abstract
Mutations in the TNNT1 gene cause an infantile, lethal form of myopathy named "Amish" Nemaline Myopathy. Adult patients are very rarely described. We report a 49-year-old patient who presented a slowly progressive phenotype characterized by myalgia, exercise intolerance and dyspnea since infancy. In adult life she lapsed into a coma as a result of acute respiratory failure, with the need of tracheostomy, subsequently removed once her respiratory condition improved. Afterwards, non-invasive ventilation was started. Short stature, contractures, a small size posterior cranial fossa and osteonecrosis were additional clinical findings. Muscle MRI showed minor hypotrophy and degenerative changes of the muscles of the posterior thigh compartment and involvement of the paraspinal, medial gastrocnemius and soleus muscles with sparing of the gracilis muscle. Muscle biopsy revealed multiminicores and nemaline rods. Genetic analysis identified a new pathogenetic biallelic deletion c.786delG p.(Lys263Serfs*36) in exon 13 of TNNT1 gene. This case confirms that recessive mutations in TNNT1 gene can manifest mainly with respiratory failure in adult life.
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Affiliation(s)
- Antonio Petrucci
- Center for Neuromuscular and Neurological Rare Diseases, Neuroscience Department, San Camillo-Forlanini Hospital, Rome, Italy
| | - Guido Primiano
- UOC Neurofisiopatologia, Fondazione Policlinico Universitario A. Gemelli IRCCS, Largo Agostino Gemelli 8, Rome 00168, Italy; Dipartimento Universitario di Neuroscienze, Università Cattolica del Sacro Cuore, Roma, Italy.
| | - Marco Savarese
- Folkhälsan Research Center, Helsinki, Finland; Department of Medical Genetics, Medicum, University of Helsinki, Helsinki, Finland
| | - Cristina Sancricca
- UOC Neurofisiopatologia, Fondazione Policlinico Universitario A. Gemelli IRCCS, Largo Agostino Gemelli 8, Rome 00168, Italy; Dipartimento Universitario di Neuroscienze, Università Cattolica del Sacro Cuore, Roma, Italy
| | - Bjarne Udd
- Folkhälsan Research Center, Helsinki, Finland; Department of Medical Genetics, Medicum, University of Helsinki, Helsinki, Finland; Neuromuscular Research Center, Tampere University and University Hospital, Tampere, Finland; Department of Neurology, Vaasa Central Hospital, Vaasa, Finland
| | - Serenella Servidei
- UOC Neurofisiopatologia, Fondazione Policlinico Universitario A. Gemelli IRCCS, Largo Agostino Gemelli 8, Rome 00168, Italy; Dipartimento Universitario di Neuroscienze, Università Cattolica del Sacro Cuore, Roma, Italy
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15
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Géraud J, Dieterich K, Rendu J, Uro Coste E, Dobrzynski M, Marcorelle P, Ioos C, Romero NB, Baudou E, Brocard J, Coville AC, Fauré J, Koenig M, Juntas Morales R, Lacène E, Madelaine A, Marty I, Pegeot H, Theze C, Siegfried A, Cossee M, Cances C. Clinical phenotype and loss of the slow skeletal muscle troponin T in three new patients with recessive TNNT1 nemaline myopathy. J Med Genet 2020; 58:602-608. [PMID: 32994279 PMCID: PMC8394741 DOI: 10.1136/jmedgenet-2019-106714] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2019] [Revised: 06/12/2020] [Accepted: 07/05/2020] [Indexed: 01/08/2023]
Abstract
Background Congenital nemaline myopathies are rare pathologies characterised by muscle weakness and rod-shaped inclusions in the muscle fibres. Methods Using next-generation sequencing, we identified three patients with pathogenic variants in the Troponin T type 1 (TNNT1) gene, coding for the troponin T (TNT) skeletal muscle isoform. Results The clinical phenotype was similar in all patients, associating hypotonia, orthopaedic deformities and progressive chronic respiratory failure, leading to early death. The anatomopathological phenotype was characterised by a disproportion in the muscle fibre size, endomysial fibrosis and nemaline rods. Molecular analyses of TNNT1 revealed a homozygous deletion of exons 8 and 9 in patient 1; a heterozygous nonsense mutation in exon 9 and retention of part of intron 4 in muscle transcripts in patient 2; and a homozygous, very early nonsense mutation in patient 3. Western blot analyses confirmed the absence of the TNT protein resulting from these mutations. Discussion The clinical and anatomopathological presentations of our patients reinforce the homogeneous character of the phenotype associated with recessive TNNT1 mutations. Previous studies revealed an impact of recessive variants on the tropomyosin-binding affinity of TNT. We report in our patients a complete loss of TNT protein due to open reading frame disruption or to post-translational degradation of TNT.
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Affiliation(s)
- Justine Géraud
- Neuropediatric Department, University Hospital Centre Toulouse, Toulouse, France
| | - Klaus Dieterich
- INSERM U1216, Grenoble Alpes University Hospital, Grenoble, France.,INSERM U1037, Cancer Research Center of Toulouse (CRCT), Department of Pathology, Toulouse University Hospital, Toulouse, France
| | - John Rendu
- INSERM U1216, Grenoble Alpes University Hospital, Grenoble, France.,INSERM U1216, University of Grenoble Alpes, Grenoble, France
| | - Emmanuelle Uro Coste
- INSERM U1037, Cancer Research Center of Toulouse (CRCT), Department of Pathology, Toulouse University Hospital, Toulouse, France
| | | | - Pascale Marcorelle
- Pathology Department, Brest University Hospital, Morvan Hospital, Brest, France
| | - Christine Ioos
- Neuropediatric Department, Garches University Hospital Center, Garches, France
| | - Norma Beatriz Romero
- UMRS974, CNRS FRE3617, Center for Research in Myology, INSERM, CNRS, Sorbonne University, UPMC University of Paris 06, Paris, France.,Myology Institute, Assistance Publique-Hôpitaux de Paris, Pitié-Salpêtrière University Hospital, Paris, France
| | - Eloise Baudou
- Neuropediatric Department, University Hospital Centre Toulouse, Toulouse, France
| | - Julie Brocard
- INSERM U1216, Grenoble Alpes University Hospital, Grenoble, France.,INSERM U1216, University of Grenoble Alpes, Grenoble, France
| | - Anne-Cécile Coville
- Neuropediatric Department, University Hospital Centre Toulouse, Toulouse, France
| | - Julien Fauré
- INSERM U1216, Grenoble Alpes University Hospital, Grenoble, France.,INSERM U1216, University of Grenoble Alpes, Grenoble, France
| | - Michel Koenig
- Molecular Genetics Laboratory, LGMR, Montpellier University Hospital Centre, University of Montpellier, Montpellier, France
| | - Raul Juntas Morales
- Molecular Genetics Laboratory, LGMR, Montpellier University Hospital Centre, University of Montpellier, Montpellier, France
| | - Emmanuelle Lacène
- UMRS974, CNRS FRE3617, Center for Research in Myology, INSERM, CNRS, Sorbonne University, UPMC University of Paris 06, Paris, France.,Myology Institute, Assistance Publique-Hôpitaux de Paris, Pitié-Salpêtrière University Hospital, Paris, France
| | - Angéline Madelaine
- UMRS974, CNRS FRE3617, Center for Research in Myology, INSERM, CNRS, Sorbonne University, UPMC University of Paris 06, Paris, France.,Myology Institute, Assistance Publique-Hôpitaux de Paris, Pitié-Salpêtrière University Hospital, Paris, France
| | - Isabelle Marty
- INSERM U1216, Grenoble Alpes University Hospital, Grenoble, France.,INSERM U1216, University of Grenoble Alpes, Grenoble, France
| | - Henri Pegeot
- Molecular Genetics Laboratory, LGMR, Montpellier University Hospital Centre, University of Montpellier, Montpellier, France
| | - Corinne Theze
- Molecular Genetics Laboratory, LGMR, Montpellier University Hospital Centre, University of Montpellier, Montpellier, France
| | | | - Mireille Cossee
- Molecular Genetics Laboratory, LGMR, Montpellier University Hospital Centre, University of Montpellier, Montpellier, France
| | - Claude Cances
- Neuropediatric Department, University Hospital Centre Toulouse, Toulouse, France
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16
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Clayton JS, McNamara EL, Goullee H, Conijn S, Muthsam K, Musk GC, Coote D, Kijas J, Testa AC, Taylor RL, O’Hara AJ, Groth D, Ottenheijm C, Ravenscroft G, Laing NG, Nowak KJ. Ovine congenital progressive muscular dystrophy (OCPMD) is a model of TNNT1 congenital myopathy. Acta Neuropathol Commun 2020; 8:142. [PMID: 32819427 PMCID: PMC7441672 DOI: 10.1186/s40478-020-01017-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2020] [Accepted: 08/10/2020] [Indexed: 12/21/2022] Open
Abstract
Ovine congenital progressive muscular dystrophy (OCPMD) was first described in Merino sheep flocks in Queensland and Western Australia in the 1960s and 1970s. The most prominent feature of the disease is a distinctive gait with stiffness of the hind limbs that can be seen as early as 3 weeks after birth. The disease is progressive. Histopathological examination had revealed dystrophic changes specifically in type I (slow) myofibres, while electron microscopy had demonstrated abundant nemaline bodies. Therefore, it was never certain whether the disease was a dystrophy or a congenital myopathy with dystrophic features. In this study, we performed whole genome sequencing of OCPMD sheep and identified a single base deletion at the splice donor site (+ 1) of intron 13 in the type I myofibre-specific TNNT1 gene (KT218690 c.614 + 1delG). All affected sheep were homozygous for this variant. Examination of TNNT1 splicing by RT-PCR showed intron retention and premature termination, which disrupts the highly conserved 14 amino acid C-terminus. The variant did not reduce TNNT1 protein levels or affect its localization but impaired its ability to modulate muscle contraction in response to Ca2+ levels. Identification of the causative variant in TNNT1 finally clarifies that the OCPMD sheep is in fact a large animal model of TNNT1 congenital myopathy. This model could now be used for testing molecular or gene therapies.
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Affiliation(s)
- Joshua S. Clayton
- Harry Perkins Institute of Medical Research, Queen Elizabeth II Medical Centre, Nedlands, 6009 WA Australia
- Centre for Medical Research, Queen Elizabeth II Medical Centre, University of Western Australia, Nedlands, 6009 WA Australia
| | - Elyshia L. McNamara
- Harry Perkins Institute of Medical Research, Queen Elizabeth II Medical Centre, Nedlands, 6009 WA Australia
- Centre for Medical Research, Queen Elizabeth II Medical Centre, University of Western Australia, Nedlands, 6009 WA Australia
| | - Hayley Goullee
- Harry Perkins Institute of Medical Research, Queen Elizabeth II Medical Centre, Nedlands, 6009 WA Australia
- Centre for Medical Research, Queen Elizabeth II Medical Centre, University of Western Australia, Nedlands, 6009 WA Australia
| | - Stefan Conijn
- Department of Physiology, Amsterdam University Medical Center (Location VUmc), Amsterdam, Netherlands
| | - Keren Muthsam
- Animal Care Services, University of Western Australia, Nedlands, 6009 WA Australia
| | - Gabrielle C. Musk
- Animal Care Services, University of Western Australia, Nedlands, 6009 WA Australia
| | - David Coote
- Harry Perkins Institute of Medical Research, Queen Elizabeth II Medical Centre, Nedlands, 6009 WA Australia
- Centre for Medical Research, Queen Elizabeth II Medical Centre, University of Western Australia, Nedlands, 6009 WA Australia
| | - James Kijas
- Commonwealth Scientific and Industrial Research Organisation Agriculture and Food, Queensland Bioscience Precinct, Brisbane, 4067 QLD Australia
| | - Alison C. Testa
- Harry Perkins Institute of Medical Research, Queen Elizabeth II Medical Centre, Nedlands, 6009 WA Australia
- Centre for Medical Research, Queen Elizabeth II Medical Centre, University of Western Australia, Nedlands, 6009 WA Australia
| | - Rhonda L. Taylor
- Harry Perkins Institute of Medical Research, Queen Elizabeth II Medical Centre, Nedlands, 6009 WA Australia
- Centre for Medical Research, Queen Elizabeth II Medical Centre, University of Western Australia, Nedlands, 6009 WA Australia
- Faculty of Health and Medical Sciences, School of Biomedical Sciences, Queen Elizabeth II Medical Centre, University of Western Australia, Nedlands, 6009 WA Australia
| | - Amanda J. O’Hara
- School of Veterinary Medicine, Murdoch University, Murdoch, 6150 WA Australia
| | - David Groth
- School of Pharmacy and Biomedical Sciences, CHIRI Biosciences Research Precinct, Curtin University, Bentley, 6102 WA Australia
| | - Coen Ottenheijm
- Department of Physiology, Amsterdam University Medical Center (Location VUmc), Amsterdam, Netherlands
| | - Gianina Ravenscroft
- Harry Perkins Institute of Medical Research, Queen Elizabeth II Medical Centre, Nedlands, 6009 WA Australia
- Centre for Medical Research, Queen Elizabeth II Medical Centre, University of Western Australia, Nedlands, 6009 WA Australia
| | - Nigel G. Laing
- Harry Perkins Institute of Medical Research, Queen Elizabeth II Medical Centre, Nedlands, 6009 WA Australia
- Centre for Medical Research, Queen Elizabeth II Medical Centre, University of Western Australia, Nedlands, 6009 WA Australia
| | - Kristen J. Nowak
- Harry Perkins Institute of Medical Research, Queen Elizabeth II Medical Centre, Nedlands, 6009 WA Australia
- Centre for Medical Research, Queen Elizabeth II Medical Centre, University of Western Australia, Nedlands, 6009 WA Australia
- Faculty of Health and Medical Sciences, School of Biomedical Sciences, Queen Elizabeth II Medical Centre, University of Western Australia, Nedlands, 6009 WA Australia
- Office of Population Health Genomics, Public and Aboriginal Health Division, Western Australian Department of Health, East Perth, 6004 WA Australia
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17
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Papadimas GK, Xirou S, Kararizou E, Papadopoulos C. Update on Congenital Myopathies in Adulthood. Int J Mol Sci 2020; 21:ijms21103694. [PMID: 32456280 PMCID: PMC7279481 DOI: 10.3390/ijms21103694] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2020] [Revised: 05/17/2020] [Accepted: 05/19/2020] [Indexed: 12/11/2022] Open
Abstract
Congenital myopathies (CMs) constitute a group of heterogenous rare inherited muscle diseases with different incidences. They are traditionally grouped based on characteristic histopathological findings revealed on muscle biopsy. In recent decades, the ever-increasing application of modern genetic technologies has not just improved our understanding of their pathophysiology, but also expanded their phenotypic spectrum and contributed to a more genetically based approach for their classification. Later onset forms of CMs are increasingly recognised. They are often considered milder with slower progression, variable clinical presentations and different modes of inheritance. We reviewed the key features and genetic basis of late onset CMs with a special emphasis on those forms that may first manifest in adulthood.
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18
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Wang Q, Hu Z, Chang X, Yu M, Xie Z, Lv H, Zhang W, Xiong H, Yuan Y, Wang Z. Mutational and clinical spectrum in a cohort of Chinese patients with hereditary nemaline myopathy. Clin Genet 2020; 97:878-889. [PMID: 32222963 DOI: 10.1111/cge.13745] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2020] [Revised: 03/23/2020] [Accepted: 03/23/2020] [Indexed: 12/12/2022]
Abstract
Hereditary nemaline myopathy (NM) is one of the most common congenital myopathies with the histopathological findings of nemaline bodies. We used targeted next-generation sequencing to identify causative mutations in 48 NM patients with confirmed myopathological diagnosis, analyze the mutational spectrum and phenotypic features. Furthermore, reverse transcription polymerase chain reaction (RT-PCR) was used to confirm the pathogenic effect of one nebulin (NEB) splicing variant. The results showed that variants were found in five NM-associated genes, including NEB, actin alpha 1 (ACTA1), troponin T1, Kelch repeat and BTB domain-containing 13, and cofilin-2, in 34 (73.9%), 7 (15.2%), 3 (6.5%), 1 (2.2%), and 1 (2.2%) patients, respectively, in a total of 46/48 (95.8%) NM patients. Of the total 64 variants identified, 51 were novel variants including 26 pathogenic, 1 probably pathogenic, and 24 variant of uncertain significance (VUS). Notably, one NEB splicing mutation, c.21417+3A>G causing exon 144 splicing (NM_001164508.1), as confirmed by RT-PCR, was found in 52.9% (18 patients) of NEB variant-carrying patients. Typical congenital NM, the most common clinical subtype (60.4%), was associated with five NM genes. We concluded that hereditary NM showed a highly variable genetic spectrum. NEB was the most frequent causative gene in this Chinese cohort, followed by ACTA1. We found a hotspot splicing mutation in NEB among Chinese cohort.
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Affiliation(s)
- Qi Wang
- Department of Neurology, Peking University First Hospital, Beijing, China
| | - Zhenxian Hu
- Department of Neurology, Peking University First Hospital, Beijing, China
| | - Xingzhi Chang
- Department of Pediatrics, Peking University First Hospital, Beijing, China
| | - Meng Yu
- Department of Neurology, Peking University First Hospital, Beijing, China
| | - Zhiying Xie
- Department of Neurology, Peking University First Hospital, Beijing, China
| | - He Lv
- Department of Neurology, Peking University First Hospital, Beijing, China
| | - Wei Zhang
- Department of Neurology, Peking University First Hospital, Beijing, China
| | - Hui Xiong
- Department of Pediatrics, Peking University First Hospital, Beijing, China
| | - Yun Yuan
- Department of Neurology, Peking University First Hospital, Beijing, China
| | - Zhaoxia Wang
- Department of Neurology, Peking University First Hospital, Beijing, China
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19
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Pellerin D, Aykanat A, Ellezam B, Troiano EC, Karamchandani J, Dicaire MJ, Petitclerc M, Robertson R, Allard-Chamard X, Brunet D, Konersman CG, Mathieu J, Warman Chardon J, Gupta VA, Beggs AH, Brais B, Chrestian N. Novel Recessive TNNT1 Congenital Core-Rod Myopathy in French Canadians. Ann Neurol 2020; 87:568-583. [PMID: 31970803 DOI: 10.1002/ana.25685] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2019] [Revised: 01/06/2020] [Accepted: 01/19/2020] [Indexed: 12/21/2022]
Abstract
OBJECTIVE Recessive null variants of the slow skeletal muscle troponin T1 (TNNT1) gene are a rare cause of nemaline myopathy that is fatal in infancy due to respiratory insufficiency. Muscle biopsy shows rods and fiber type disproportion. We report on 4 French Canadians with a novel form of recessive congenital TNNT1 core-rod myopathy. METHODS Patients underwent full clinical characterization, lower limb magnetic resonance imaging (MRI), muscle biopsy, and genetic testing. A zebrafish loss-of-function model using morpholinos was created to assess the pathogenicity of the identified variant. Wild-type or mutated human TNNT1 mRNAs were coinjected with morpholinos to assess their abilities to rescue the morphant phenotype. RESULTS Three adults and 1 child shared a novel missense homozygous variant in the TNNT1 gene (NM_003283.6: c.287T > C; p.Leu96Pro). They developed from childhood very slowly progressive limb-girdle weakness with rigid spine and disabling contractures. They suffered from restrictive lung disease requiring noninvasive mechanical ventilation in 3 patients, as well as recurrent episodes of rhabdomyolysis triggered by infections, which were relieved by dantrolene in 1 patient. Older patients remained ambulatory into their 60s. MRI of the leg muscles showed fibrofatty infiltration predominating in the posterior thigh and the deep posterior leg compartments. Muscle biopsies showed multiminicores and lobulated fibers, rods in half the patients, and no fiber type disproportion. Wild-type TNNT1 mRNA rescued the zebrafish morphants, but mutant transcripts failed to do so. INTERPRETATION This study expands the phenotypic spectrum of TNNT1 myopathy and provides functional evidence for the pathogenicity of the newly identified missense mutation. ANN NEUROL 2020;87:568-583.
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Affiliation(s)
- David Pellerin
- Department of Neurology and Neurosurgery, Montreal Neurological Hospital and Institute, McGill University, Montreal, Quebec, Canada
| | - Asli Aykanat
- Division of Genetics and Genomics, The Manton Center for Orphan Disease Research, Boston Children's Hospital, Harvard Medical School, Boston, MA
| | - Benjamin Ellezam
- Department of Pathology, Centre Hospitalier Universitaire Sainte-Justine, Université de Montréal, Montreal, Quebec, Canada
| | - Emily C Troiano
- Division of Genetics and Genomics, The Manton Center for Orphan Disease Research, Boston Children's Hospital, Harvard Medical School, Boston, MA
| | - Jason Karamchandani
- Department of Pathology, Montreal Neurological Hospital and Institute, McGill University, Montreal, Quebec, Canada
| | - Marie-Josée Dicaire
- Department of Neurology and Neurosurgery, Montreal Neurological Hospital and Institute, McGill University, Montreal, Quebec, Canada
| | - Marc Petitclerc
- Department of Neurology, Hôpital Hôtel-Dieu de Lévis, Lévis, Quebec, Canada
| | - Rebecca Robertson
- Department of Neurology and Neurosurgery, Montreal Neurological Hospital and Institute, McGill University, Montreal, Quebec, Canada
| | - Xavier Allard-Chamard
- Department of Neurology and Neurosurgery, Montreal Neurological Hospital and Institute, McGill University, Montreal, Quebec, Canada
| | - Denis Brunet
- Department of Neurology, Hôpital de l'Enfant Jésus, Université Laval, Quebec City, Quebec, Canada
| | | | - Jean Mathieu
- Faculty of Medicine and Health Sciences, Université de Sherbrooke, Sherbrooke, Quebec, Canada.,Neuromuscular Disease Clinic, Centre Intégré Universitaire de Santé et de Services Sociaux du Saguenay-Lac-Saint-Jean, Jonquière, Quebec, Canada
| | - Jodi Warman Chardon
- Department of Neurosciences, Ottawa Hospital Research Institute, Ottawa, Ontario, Canada
| | - Vandana A Gupta
- Division of Genetics, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA
| | - Alan H Beggs
- Division of Genetics and Genomics, The Manton Center for Orphan Disease Research, Boston Children's Hospital, Harvard Medical School, Boston, MA
| | - Bernard Brais
- Department of Neurology and Neurosurgery, Montreal Neurological Hospital and Institute, McGill University, Montreal, Quebec, Canada.,Neuromuscular Disease Clinic, Centre Intégré Universitaire de Santé et de Services Sociaux du Saguenay-Lac-Saint-Jean, Jonquière, Quebec, Canada.,Department of Human Genetics, McGill University, Montreal, Quebec, Canada
| | - Nicolas Chrestian
- Department of Child Neurology, Centre Hospitalier de l'Université Laval et Centre Mère-Enfant Soleil, Université Laval, Quebec City, Quebec, Canada
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20
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D'Amico A, Fattori F, Fiorillo C, Paglietti MG, Testa MBC, Verardo M, Catteruccia M, Bruno C, Bertini E. 'Amish Nemaline Myopathy' in 2 Italian siblings harbouring a novel homozygous mutation in Troponin-I gene. Neuromuscul Disord 2019; 29:766-770. [PMID: 31604653 DOI: 10.1016/j.nmd.2019.09.005] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2019] [Revised: 06/10/2019] [Accepted: 09/02/2019] [Indexed: 02/06/2023]
Abstract
Amish Nemaline Myopathy is a severe form of nemaline myopathy associated to mutation in TNNT1 gene, firstly reported among the Old Order Amish. Here we report two Italian siblings who manifested, by the age of 7 months, progressive and severe muscle weakness and wasting, respiratory insufficiency, pectus carinatum deformity and failure to thrive. Muscle biopsy was consistent with nemaline myopathy and novel homozygous missense mutation in TNNT1 was found. Our cases expand the mutational spectrum of TNNT1, confirm the invariable peculiar clinical phenotype also outside the Amish population, and suggest that TNNT1 should be considered for molecular analysis in NM patients with chest deformities and progressive contractures.
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Affiliation(s)
- Adele D'Amico
- Unit of Muscular and Neurodegenerative Disorders, Department of Neurosciences and Neurorehabilitation, Bambino Gesù Children's Hospital, Piazza S. Onofrio 4, 00165 Rome, Italy.
| | - Fabiana Fattori
- Unit of Muscular and Neurodegenerative Disorders, Department of Neurosciences and Neurorehabilitation, Bambino Gesù Children's Hospital, Piazza S. Onofrio 4, 00165 Rome, Italy
| | - Chiara Fiorillo
- Paediatric Neurology and Neuromuscular Disorders Unit, Department of Neurosciences, Rehabilitation, Ophthalmology, Genetics, Maternal and Child Health, University of Genoa, Istituto Giannina Gaslini, Genoa, Italy
| | - Maria Giovanna Paglietti
- Respiratory Unit, Academic Department of Pediatrics, Bambino Gesù Children's Hospital, IRCCS, Piazza di Sant' Onofrio 4, 00165 Rome, Italy
| | - Maria Beatrice Chiarini Testa
- Respiratory Unit, Academic Department of Pediatrics, Bambino Gesù Children's Hospital, IRCCS, Piazza di Sant' Onofrio 4, 00165 Rome, Italy
| | - Margherita Verardo
- Unit of Muscular and Neurodegenerative Disorders, Department of Neurosciences and Neurorehabilitation, Bambino Gesù Children's Hospital, Piazza S. Onofrio 4, 00165 Rome, Italy
| | - Michela Catteruccia
- Unit of Muscular and Neurodegenerative Disorders, Department of Neurosciences and Neurorehabilitation, Bambino Gesù Children's Hospital, Piazza S. Onofrio 4, 00165 Rome, Italy
| | - Claudio Bruno
- Center of Translational and Experimental Myology, Istituto Giannina Gaslini, Genova, Italy
| | - Enrico Bertini
- Unit of Muscular and Neurodegenerative Disorders, Department of Neurosciences and Neurorehabilitation, Bambino Gesù Children's Hospital, Piazza S. Onofrio 4, 00165 Rome, Italy
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21
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Sewry CA, Laitila JM, Wallgren-Pettersson C. Nemaline myopathies: a current view. J Muscle Res Cell Motil 2019; 40:111-126. [PMID: 31228046 PMCID: PMC6726674 DOI: 10.1007/s10974-019-09519-9] [Citation(s) in RCA: 110] [Impact Index Per Article: 22.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2019] [Accepted: 05/29/2019] [Indexed: 12/13/2022]
Abstract
Nemaline myopathies are a heterogenous group of congenital myopathies caused by de novo, dominantly or recessively inherited mutations in at least twelve genes. The genes encoding skeletal α-actin (ACTA1) and nebulin (NEB) are the commonest genetic cause. Most patients have congenital onset characterized by muscle weakness and hypotonia, but the spectrum of clinical phenotypes is broad, ranging from severe neonatal presentations to onset of a milder disorder in childhood. Most patients with adult onset have an autoimmune-related myopathy with a progressive course. The wide application of massively parallel sequencing methods is increasing the number of known causative genes and broadening the range of clinical phenotypes. Nemaline myopathies are identified by the presence of structures that are rod-like or ovoid in shape with electron microscopy, and with light microscopy stain red with the modified Gömöri trichrome technique. These rods or nemaline bodies are derived from Z lines (also known as Z discs or Z disks) and have a similar lattice structure and protein content. Their shape in patients with mutations in KLHL40 and LMOD3 is distinctive and can be useful for diagnosis. The number and distribution of nemaline bodies varies between fibres and different muscles but does not correlate with severity or prognosis. Additional pathological features such as caps, cores and fibre type disproportion are associated with the same genes as those known to cause the presence of rods. Animal models are advancing the understanding of the effects of various mutations in different genes and paving the way for the development of therapies, which at present only manage symptoms and are aimed at maintaining muscle strength, joint mobility, ambulation, respiration and independence in the activities of daily living.
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Affiliation(s)
- Caroline A Sewry
- Dubowitz Neuromuscular Centre, UCL Institute of Child Health and Great Ormond Street Hospital, 30 Guilford Street, London, WC1N 1EH, UK. .,Wolfson Centre of Inherited Neuromuscular Disorders, RJAH Orthopaedic Hospital, Oswestry, SY10 7AG, UK.
| | - Jenni M Laitila
- Folkhälsan Institute of Genetics, Folkhälsan Research Center, Helsinki, Finland.,Department of Medical and Clinical Genetics, Medicum, University of Helsinki, Helsinki, Finland
| | - Carina Wallgren-Pettersson
- Folkhälsan Institute of Genetics, Folkhälsan Research Center, Helsinki, Finland.,Department of Medical and Clinical Genetics, Medicum, University of Helsinki, Helsinki, Finland
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22
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Fox MD, Carson VJ, Feng HZ, Lawlor MW, Gray JT, Brigatti KW, Jin JP, Strauss KA. TNNT1 nemaline myopathy: natural history and therapeutic frontier. Hum Mol Genet 2019; 27:3272-3282. [PMID: 29931346 DOI: 10.1093/hmg/ddy233] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2018] [Accepted: 06/06/2018] [Indexed: 02/03/2023] Open
Abstract
We describe the natural history of 'Amish' nemaline myopathy (ANM), an infantile-onset, lethal disease linked to a pathogenic c.505G>T nonsense mutation of TNNT1, which encodes the slow fiber isoform of troponin T (TNNT1; a.k.a. TnT). The TNNT1 c.505G>T allele has a carrier frequency of 6.5% within Old Order Amish settlements of North America. We collected natural history data for 106 ANM patients born between 1923 and 2017. Over the last two decades, mean age of molecular diagnosis was 16 ± 27 days. TNNT1 c.505G>T homozygotes were normal weight at birth but failed to thrive by age 9 months. Presenting neonatal signs were axial hypotonia, hip and shoulder stiffness, and tremors, followed by progressive muscle weakness, atrophy and contractures. Affected children developed thoracic rigidity, pectus carinatum and restrictive lung disease during infancy, and all succumbed to respiratory failure by 6 years of age (median survival 18 months, range 0.2-66 months). Muscle histology from two affected children showed marked fiber size variation owing to both Type 1 myofiber smallness (hypotrophy) and Type 2 fiber hypertrophy, with evidence of nemaline rods, myofibrillar disarray and vacuolar pathology in both fiber types. The truncated slow TNNT1 (TnT) fragment (p.Glu180Ter) was undetectable in ANM muscle, reflecting its rapid proteolysis and clearance from sarcoplasm. Similar functional and histological phenotypes were observed in other human cohorts and two transgenic murine models (Tnnt1-/- and Tnnt1 c.505G>T). These findings have implications for emerging molecular therapies, including the suitably of TNNT1 gene replacement for newborns with ANM or other TNNT1-associated myopathies.
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Affiliation(s)
- Michael D Fox
- Clinic for Special Children, Strasburg, PA, USA
- Department of Pediatrics, Sidney Kimmel Medical College at Thomas Jefferson University, Philadelphia, PA, USA
- Diagnostic Referral Division, Nemours/Alfred I. duPont Hospital for Children, Wilmington, DE, USA
| | | | - Han-Zhong Feng
- Department of Physiology, Wayne State University School of Medicine, Detroit, MI, USA
| | - Michael W Lawlor
- Department of Pathology and Laboratory Medicine and Neuroscience Research Center, The Medical College of Wisconsin, Milwaukee, WI, USA
| | - John T Gray
- Audentes Therapeutics, San Francisco, CA, USA
| | | | - J-P Jin
- Department of Physiology, Wayne State University School of Medicine, Detroit, MI, USA
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23
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Caffarelli C, Santamaria F, Di Mauro D, Mastrorilli C, Montella S, Tchana B, Valerio G, Verrotti A, Valenzise M, Bernasconi S, Corsello G. Advances in pediatrics in 2017: current practices and challenges in allergy, endocrinology, gastroenterology, genetics, immunology, infectious diseases, neonatology, nephrology, neurology, pulmonology from the perspective of Italian Journal of Pediatrics. Ital J Pediatr 2018; 44:82. [PMID: 30016966 PMCID: PMC6050676 DOI: 10.1186/s13052-018-0524-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/03/2018] [Accepted: 07/03/2018] [Indexed: 11/25/2022] Open
Abstract
This review provides an overview of a remarkable number of significant studies in pediatrics that have been published over the past year in the Italian Journal of Pediatrics. We have selected information from papers presented in the Journal that deal with allergy, endocrinology, gastroenterology, genetics, immunology, infectious diseases, neonatology, nephrology, neurology, pulmonology. The relevant epidemiologic findings, and developments in prevention, diagnosis and treatment of the last year have been discussed and placed in context. We think that advances achieved in 2017 will help readers to make the future of patients better.
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Affiliation(s)
- Carlo Caffarelli
- Clinica Pediatrica, Department of Medicine and Surgery, Azienda Ospedaliera-Universitaria, University of Parma, Parma, Italy
| | - Francesca Santamaria
- Department of Translational Medical Sciences, Federico II University, Naples, Italy
| | - Dora Di Mauro
- Clinica Pediatrica, Department of Medicine and Surgery, Azienda Ospedaliera-Universitaria, University of Parma, Parma, Italy
| | - Carla Mastrorilli
- Clinica Pediatrica, Department of Medicine and Surgery, Azienda Ospedaliera-Universitaria, University of Parma, Parma, Italy
| | - Silvia Montella
- Department of Translational Medical Sciences, Federico II University, Naples, Italy
| | - Bertrand Tchana
- Cardiologia Pediatrica, Azienda Ospedaliera-Universitaria, Parma, Italy
| | - Giuliana Valerio
- Pediatria, Dipartimento di Scienze Motorie e del Benessere, Università di Napoli Parthenope, Naples, Italy
| | - Alberto Verrotti
- Department of Pediatrics, University of L’Aquila, L’Aquila, Italy
| | - Mariella Valenzise
- UOC Clinica Pediatrica AOU G, Martino Università di Messina, Messina, Italy
| | - Sergio Bernasconi
- Pediatrics Honorary Member University Faculty, G D’Annunzio University of Chieti-Pescara, Chieti, Italy
| | - Giovanni Corsello
- Department of Sciences for Health Promotion and Mother and Child Care “G. D’Alessandro”, University of Palermo, Palermo, Italy
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24
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Konersman CG, Freyermuth F, Winder TL, Lawlor MW, Lagier‐Tourenne C, Patel SB. Novel autosomal dominant TNNT1 mutation causing nemaline myopathy. Mol Genet Genomic Med 2017; 5:678-691. [PMID: 29178646 PMCID: PMC5702563 DOI: 10.1002/mgg3.325] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2017] [Revised: 07/13/2017] [Accepted: 07/18/2017] [Indexed: 01/30/2023] Open
Abstract
BACKGROUND Nemaline myopathy (NEM) is one of the three major forms of congenital myopathy and is characterized by diffuse muscle weakness, hypotonia, respiratory insufficiency, and the presence of nemaline rod structures on muscle biopsy. Mutations in troponin T1 (TNNT1) is 1 of 10 genes known to cause NEM. To date, only homozygous nonsense mutations or compound heterozygous truncating or internal deletion mutations in TNNT1 gene have been identified in NEM. This extended family is of historical importance as some members were reported in the 1960s as initial evidence that NEM is a hereditary disorder. METHODS Proband and extended family underwent Sanger sequencing for TNNT1. We performed RT-PCR and immunoblot on muscle to assess TNNT1 RNA expression and protein levels in proband and father. RESULTS We report a novel heterozygous missense mutation of TNNT1 c.311A>T (p.E104V) that segregated in an autosomal dominant fashion in a large family residing in the United States. Extensive sequencing of the other known genes for NEM failed to identify any other mutant alleles. Muscle biopsies revealed a characteristic pattern of nemaline rods and severe myofiber hypotrophy that was almost entirely restricted to the type 1 fiber population. CONCLUSION This novel mutation alters a residue that is highly conserved among vertebrates. This report highlights not only a family with autosomal dominant inheritance of NEM, but that this novel mutation likely acts via a dominant negative mechanism.
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Affiliation(s)
| | - Fernande Freyermuth
- MassGeneral Institute for Neurodegenerative DiseaseDepartment of NeurologyMassachusetts General HospitalHarvard Medical SchoolCharlestownMassachusetts
- Broad Institute of Harvard University and MITCambridgeMassachusetts
| | - Thomas L. Winder
- Prevention GeneticsMarshfieldWisconsin
- Present address:
Invitae CorporationSan FranciscoCalifornia
| | - Michael W. Lawlor
- Division of Pediatric PathologyDepartment of Pathology and Laboratory Medicine and Neuroscience Research CenterMedical College of WisconsinMilwaukeeWisconsin
| | - Clotilde Lagier‐Tourenne
- MassGeneral Institute for Neurodegenerative DiseaseDepartment of NeurologyMassachusetts General HospitalHarvard Medical SchoolCharlestownMassachusetts
- Broad Institute of Harvard University and MITCambridgeMassachusetts
| | - Shailendra B. Patel
- Division of EndocrinologyMetabolism and Clinical NutritionMedical College of Wisconsin, and Clement J. Zablocki VAMCMilwaukeeWisconsin
- Present address:
Division of Endocrinology, Diabetes and MetabolismUniversity of CincinnatiCincinnatiOhio
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