1
|
Heimdörfer D, Vorleuter A, Eschlböck A, Spathopoulou A, Suarez-Cubero M, Farhan H, Reiterer V, Spanjaard M, Schaaf CP, Huber LA, Kremser L, Sarg B, Edenhofer F, Geley S, de Araujo MEG, Huettenhofer A. Truncated variants of MAGEL2 are involved in the etiologies of the Schaaf-Yang and Prader-Willi syndromes. Am J Hum Genet 2024:S0002-9297(24)00206-4. [PMID: 38908375 DOI: 10.1016/j.ajhg.2024.05.023] [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: 04/16/2024] [Revised: 05/27/2024] [Accepted: 05/29/2024] [Indexed: 06/24/2024] Open
Abstract
The neurodevelopmental disorders Prader-Willi syndrome (PWS) and Schaaf-Yang syndrome (SYS) both arise from genomic alterations within human chromosome 15q11-q13. A deletion of the SNORD116 cluster, encoding small nucleolar RNAs, or frameshift mutations within MAGEL2 result in closely related phenotypes in individuals with PWS or SYS, respectively. By investigation of their subcellular localization, we observed that in contrast to a predominant cytoplasmic localization of wild-type (WT) MAGEL2, a truncated MAGEL2 mutant was evenly distributed between the cytoplasm and the nucleus. To elucidate regulatory pathways that may underlie both diseases, we identified protein interaction partners for WT or mutant MAGEL2, in particular the survival motor neuron protein (SMN), involved in spinal muscular atrophy, and the fragile-X-messenger ribonucleoprotein (FMRP), involved in autism spectrum disorders. The interactome of the non-coding RNA SNORD116 was also investigated by RNA-CoIP. We show that WT and truncated MAGEL2 were both involved in RNA metabolism, while regulation of transcription was mainly observed for WT MAGEL2. Hence, we investigated the influence of MAGEL2 mutations on the expression of genes from the PWS locus, including the SNORD116 cluster. Thereby, we provide evidence for MAGEL2 mutants decreasing the expression of SNORD116, SNORD115, and SNORD109A, as well as protein-coding genes MKRN3 and SNRPN, thus bridging the gap between PWS and SYS.
Collapse
Affiliation(s)
- David Heimdörfer
- Institute of Genomics and RNomics, Biocenter Innsbruck, Medical University of Innsbruck, Innrain 80/82, 6020 Innsbruck, Austria.
| | - Alexander Vorleuter
- Institute of Genomics and RNomics, Biocenter Innsbruck, Medical University of Innsbruck, Innrain 80/82, 6020 Innsbruck, Austria
| | - Alexander Eschlböck
- Institute for Molecular Biology, Genomics, Stem Cell Biology & Regenerative Medicine Group, University of Innsbruck and CMBI, Technikerstr. 25, 6020 Innsbruck, Austria
| | - Angeliki Spathopoulou
- Institute for Molecular Biology, Genomics, Stem Cell Biology & Regenerative Medicine Group, University of Innsbruck and CMBI, Technikerstr. 25, 6020 Innsbruck, Austria
| | - Marta Suarez-Cubero
- Institute for Molecular Biology, Genomics, Stem Cell Biology & Regenerative Medicine Group, University of Innsbruck and CMBI, Technikerstr. 25, 6020 Innsbruck, Austria
| | - Hesso Farhan
- Institute of Pathophysiology, Biocenter, Medical University of Innsbruck, Innrain 80/82, 6020 Innsbruck, Austria
| | - Veronika Reiterer
- Institute of Pathophysiology, Biocenter, Medical University of Innsbruck, Innrain 80/82, 6020 Innsbruck, Austria
| | - Melanie Spanjaard
- Institute of Human Genetics, Heidelberg University, Im Neuenheimer Feld 366, 69120 Heidelberg, Germany
| | - Christian P Schaaf
- Institute of Human Genetics, Heidelberg University, Im Neuenheimer Feld 366, 69120 Heidelberg, Germany
| | - Lukas A Huber
- Institute of Cell Biology, Biocenter, Medical University of Innsbruck, Innrain 80/82, Innsbruck 6020, Austria
| | - Leopold Kremser
- Institute of Medical Biochemistry, Protein Core Facility, Biocenter, Medical University of Innsbruck, Innrain 80/82, 6020 Innsbruck, Austria
| | - Bettina Sarg
- Institute of Medical Biochemistry, Protein Core Facility, Biocenter, Medical University of Innsbruck, Innrain 80/82, 6020 Innsbruck, Austria
| | - Frank Edenhofer
- Institute for Molecular Biology, Genomics, Stem Cell Biology & Regenerative Medicine Group, University of Innsbruck and CMBI, Technikerstr. 25, 6020 Innsbruck, Austria
| | - Stephan Geley
- Institute of Pathophysiology, Biocenter, Medical University of Innsbruck, Innrain 80/82, 6020 Innsbruck, Austria
| | - Mariana E G de Araujo
- Institute of Cell Biology, Biocenter, Medical University of Innsbruck, Innrain 80/82, Innsbruck 6020, Austria
| | - Alexander Huettenhofer
- Institute of Genomics and RNomics, Biocenter Innsbruck, Medical University of Innsbruck, Innrain 80/82, 6020 Innsbruck, Austria.
| |
Collapse
|
2
|
Jablonka S, Yildirim E. Disease Mechanisms and Therapeutic Approaches in SMARD1-Insights from Animal Models and Cell Models. Biomedicines 2024; 12:845. [PMID: 38672198 PMCID: PMC11048220 DOI: 10.3390/biomedicines12040845] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2024] [Revised: 04/04/2024] [Accepted: 04/07/2024] [Indexed: 04/28/2024] Open
Abstract
Spinal muscular atrophy with respiratory distress type 1 (SMARD1) is a fatal childhood motoneuron disease caused by mutations in the IGHMBP2 gene. It is characterized by muscle weakness, initially affecting the distal extremities due to the degeneration of spinal α-motoneurons, and respiratory distress, due to the paralysis of the diaphragm. Infantile forms with a severe course of the disease can be distinguished from juvenile forms with a milder course. Mutations in the IGHMBP2 gene have also been found in patients with peripheral neuropathy Charcot-Marie-Tooth type 2S (CMT2S). IGHMBP2 is an ATP-dependent 5'→3' RNA helicase thought to be involved in translational mechanisms. In recent years, several animal models representing both SMARD1 forms and CMT2S have been generated to initially study disease mechanisms. Later, the models showed very well that both stem cell therapies and the delivery of the human IGHMBP2 cDNA by AAV9 approaches (AAV9-IGHMBP2) can lead to significant improvements in disease symptoms. Therefore, the SMARD1 animal models, in addition to the cellular models, provide an inexhaustible source for obtaining knowledge of disease mechanisms, disease progression at the cellular level, and deeper insights into the development of therapies against SMARD1.
Collapse
Affiliation(s)
- Sibylle Jablonka
- Institute of Clinical Neurobiology, University Hospital Würzburg, Versbacher Strasse 5, 97078 Würzburg, Germany;
| | | |
Collapse
|
3
|
Vadla GP, Singh K, Lorson CL, Lorson MA. The contribution and therapeutic implications of IGHMBP2 mutations on IGHMBP2 biochemical activity and ABT1 association. Biochim Biophys Acta Mol Basis Dis 2024; 1870:167091. [PMID: 38403020 PMCID: PMC10999323 DOI: 10.1016/j.bbadis.2024.167091] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2023] [Revised: 02/01/2024] [Accepted: 02/15/2024] [Indexed: 02/27/2024]
Abstract
Mutations within immunoglobulin mu DNA binding protein (IGHMBP2), an RNA-DNA helicase, result in SMA with respiratory distress type I (SMARD1) and Charcot Marie Tooth type 2S (CMT2S). The underlying biochemical mechanism of IGHMBP2 is unknown as well as the functional significance of IGHMBP2 mutations in disease severity. Here we report the biochemical mechanisms of IGHMBP2 disease-causing mutations D565N and H924Y, and their potential impact on therapeutic strategies. The IGHMBP2-D565N mutation has been identified in SMARD1 patients, while the IGHMBP2-H924Y mutation has been identified in CMT2S patients. For the first time, we demonstrate a correlation between the altered IGHMBP2 biochemical activity associated with the D565N and H924Y mutations and disease severity and pathology in patients and our Ighmbp2 mouse models. We show that IGHMBP2 mutations that alter the association with activator of basal transcription (ABT1) impact the ATPase and helicase activities of IGHMBP2 and the association with the 47S pre-rRNA 5' external transcribed spacer. We demonstrate that the D565N mutation impairs IGHMBP2 ATPase and helicase activities consistent with disease pathology. The H924Y mutation alters IGHMBP2 activity to a lesser extent while maintaining association with ABT1. In the context of the compound heterozygous patient, we demonstrate that the total biochemical activity associated with IGHMBP2-D565N and IGHMBP2-H924Y proteins is improved over IGHMBP2-D565N alone. Importantly, we demonstrate that the efficacy of therapeutic applications may vary based on the underlying IGHMBP2 mutations and the relative biochemical activity of the mutant IGHMBP2 protein.
Collapse
Affiliation(s)
- Gangadhar P Vadla
- Department of Veterinary Pathobiology, College of Veterinary Medicine, University of Missouri, Columbia, MO 65211, USA; Bond Life Sciences Center, University of Missouri, Columbia, MO 65211, USA
| | - Kamal Singh
- Department of Veterinary Pathobiology, College of Veterinary Medicine, University of Missouri, Columbia, MO 65211, USA; Bond Life Sciences Center, University of Missouri, Columbia, MO 65211, USA
| | - Christian L Lorson
- Department of Veterinary Pathobiology, College of Veterinary Medicine, University of Missouri, Columbia, MO 65211, USA; Bond Life Sciences Center, University of Missouri, Columbia, MO 65211, USA
| | - Monique A Lorson
- Department of Veterinary Pathobiology, College of Veterinary Medicine, University of Missouri, Columbia, MO 65211, USA; Bond Life Sciences Center, University of Missouri, Columbia, MO 65211, USA.
| |
Collapse
|
4
|
Prusty AB, Hirmer A, Sierra-Delgado JA, Huber H, Guenther UP, Schlosser A, Dybkov O, Yildirim E, Urlaub H, Meyer KC, Jablonka S, Erhard F, Fischer U. RNA helicase IGHMBP2 regulates THO complex to ensure cellular mRNA homeostasis. Cell Rep 2024; 43:113802. [PMID: 38368610 DOI: 10.1016/j.celrep.2024.113802] [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: 08/03/2023] [Revised: 12/21/2023] [Accepted: 01/31/2024] [Indexed: 02/20/2024] Open
Abstract
RNA helicases constitute a large protein family implicated in cellular RNA homeostasis and disease development. Here, we show that the RNA helicase IGHMBP2, linked to the neuromuscular disorder spinal muscular atrophy with respiratory distress type 1 (SMARD1), associates with polysomes and impacts translation of mRNAs containing short, GC-rich, and structured 5' UTRs. The absence of IGHMBP2 causes ribosome stalling at the start codon of target mRNAs, leading to reduced translation efficiency. The main mRNA targets of IGHMBP2-mediated regulation encode for components of the THO complex (THOC), linking IGHMBP2 to mRNA production and nuclear export. Accordingly, failure of IGHMBP2 regulation of THOC causes perturbations of the transcriptome and its encoded proteome, and ablation of THOC subunits phenocopies these changes. Thus, IGHMBP2 is an upstream regulator of THOC. Of note, IGHMBP2-dependent regulation of THOC is also observed in astrocytes derived from patients with SMARD1 disease, suggesting that deregulated mRNA metabolism contributes to SMARD1 etiology and may enable alternative therapeutic avenues.
Collapse
Affiliation(s)
| | - Anja Hirmer
- Department of Biochemistry 1, Biocenter, University of Würzburg, 97074 Würzburg, Germany
| | | | - Hannes Huber
- Department of Biochemistry 1, Biocenter, University of Würzburg, 97074 Würzburg, Germany
| | | | - Andreas Schlosser
- Rudolf-Virchow-Center, Center for Integrative and Translational Bioimaging, University of Würzburg, 97080 Würzburg, Germany
| | - Olexandr Dybkov
- Bioanalytical Mass Spectrometry, Max Planck Institute for Multidisciplinary Sciences, 37077 Göttingen, Germany
| | - Ezgi Yildirim
- Institute of Clinical Neurobiology, University Hospital Würzburg, 97078 Würzburg, Germany
| | - Henning Urlaub
- Bioanalytical Mass Spectrometry, Max Planck Institute for Multidisciplinary Sciences, 37077 Göttingen, Germany; Department of Clinical Chemistry, University Medical Center Göttingen, 37075 Göttingen, Germany; Cluster of Excellence "Multiscale Bioimaging: from Molecular Machines to Networks of Excitable Cells" (MBExC), University of Göttingen, Göttingen, Germany; Göttingen Center for Molecular Biosciences, University of Göttingen, Göttingen, Germany
| | - Kathrin C Meyer
- Nationwide Children's Hospital, Center for Gene Therapy, Columbus, OH 43205, USA; Department of Pediatrics, Ohio State University, Columbus, OH 43210, USA
| | - Sibylle Jablonka
- Institute of Clinical Neurobiology, University Hospital Würzburg, 97078 Würzburg, Germany
| | - Florian Erhard
- Institute for Virology and Immunobiology, University of Würzburg, 97078 Würzburg, Germany; Faculty for Informatics and Data Science, University of Regensburg, 93053 Regensburg, Germany.
| | - Utz Fischer
- Department of Biochemistry 1, Biocenter, University of Würzburg, 97074 Würzburg, Germany; Helmholtz Institute for RNA-based Infection Research (HIRI), Helmholtz Centre for Infection Research (HZI), 97080 Würzburg, Germany.
| |
Collapse
|
5
|
Tran VK, Cao MH, Nguyen TTH, Le PT, Tran HA, Vu DC, Nguyen HT, Nguyen MTP, Bui TH, Nguyen TB, Ta TV, Tran TH. A novel IGHMBP2 variant and clinical diversity in Vietnamese SMARD1 and CMT2S patients. Front Pediatr 2024; 12:1165492. [PMID: 38415210 PMCID: PMC10896978 DOI: 10.3389/fped.2024.1165492] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/14/2023] [Accepted: 01/26/2024] [Indexed: 02/29/2024] Open
Abstract
Background Pathogenic variants in the IGHMBP2 gene are associated with two distinct autosomal recessive neuromuscular disorders: spinal muscular atrophy with respiratory distress type 1 (SMARD1; OMIM #604320) and Charcot-Marie-Tooth type 2S (CMT2S; OMIM #616155). SMARD1 is a severe and fatal condition characterized by infantile-onset respiratory distress, diaphragmatic palsy, and distal muscular weakness, while CMT2S follows a milder clinical course, with slowly progressive distal muscle weakness and sensory loss, without manifestations of respiratory disorder. Methods Whole-exome sequencing of the IGHMBP2 gene was performed for eight Vietnamese patients with IGHMBP2-related neuromuscular disorders including five patients with SMARD1 and the others with CMT2S. Results We identified one novel IGHMBP2 variant c.1574T > C (p.Leu525Pro) in a SMARD1 patient. Besides that, two patients shared the same pathogenic variants (c.1235 + 3A > G/c.1334A > C) but presented completely different clinical courses: one with SMARD1 who deceased at 8 months of age, the other with CMT2S was alive at 3 years old without any respiratory distress. Conclusion This study is the first to report IGHMBP-2-related neuromuscular disorders in Vietnam. A novel IGHMBP2 variant c.1574T > C (p.Leu525Pro) expressing SMARD1 phenotype was detected. The presence of three patients with the same genotype but distinct clinical outcomes suggested the interaction of variants and other factors including relating modified genes in the mechanism of various phenotypes.
Collapse
Affiliation(s)
- Van Khanh Tran
- Center for Gene and Protein Research, Hanoi Medical University, Hanoi, Vietnam
- Department of Molecular Pathology, Faculty of Medical Laboratory Technology, Hanoi Medical University, Hanoi, Vietnam
| | - My Ha Cao
- Center for Gene and Protein Research, Hanoi Medical University, Hanoi, Vietnam
| | | | - Phuong Thi Le
- Center for Gene and Protein Research, Hanoi Medical University, Hanoi, Vietnam
| | - Hai Anh Tran
- Center for Gene and Protein Research, Hanoi Medical University, Hanoi, Vietnam
| | - Dung Chi Vu
- Department of Endocrinology, Metabolism and Genetics, National Hospital of Pediatrics, Hanoi, Vietnam
| | - Ha Thu Nguyen
- Department of Endocrinology, Metabolism and Genetics, National Hospital of Pediatrics, Hanoi, Vietnam
| | | | - The-Hung Bui
- Center for Gene and Protein Research, Hanoi Medical University, Hanoi, Vietnam
- Center for Molecular Medicine, Clinical Genetics Unit, Karolinska Institute, Karolinska University Hospital, Stockholm, Sweden
| | - Thanh Binh Nguyen
- Center for Gene and Protein Research, Hanoi Medical University, Hanoi, Vietnam
| | - Thanh Van Ta
- Department of Biochemistry, Hanoi Medical University, Hanoi, Vietnam
- Clinical Laboratory, Hanoi Medical University Hospital, Hanoi Medical University, Hanoi, Vietnam
| | - Thinh Huy Tran
- Department of Biochemistry, Hanoi Medical University, Hanoi, Vietnam
- Clinical Laboratory, Hanoi Medical University Hospital, Hanoi Medical University, Hanoi, Vietnam
| |
Collapse
|
6
|
Tian Y, Xing J, Shi Y, Yuan E. Exploring the relationship between IGHMBP2 gene mutations and spinal muscular atrophy with respiratory distress type 1 and Charcot-Marie-Tooth disease type 2S: a systematic review. Front Neurosci 2023; 17:1252075. [PMID: 38046662 PMCID: PMC10690808 DOI: 10.3389/fnins.2023.1252075] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2023] [Accepted: 11/03/2023] [Indexed: 12/05/2023] Open
Abstract
Background IGHMBP2 is a crucial gene for the development and maintenance of the nervous system, especially in the survival of motor neurons. Mutations in this gene have been associated with spinal muscular atrophy with respiratory distress type 1 (SMARD1) and Charcot-Marie-Tooth disease type 2S (CMT2S). Methods We conducted a systematic literature search using the PubMed database to identify studies published up to April 1st, 2023, that investigated the association between IGHMBP2 mutations and SMARD1 or CMT2S. We compared the non-truncating mutations and truncating mutations of the IGHMBP2 gene and selected high-frequency mutations of the IGHMBP2 gene. Results We identified 52 articles that investigated the association between IGHMBP2 mutations and SMARD1/CMT2S. We found 6 hotspot mutations of the IGHMBP2 gene. The truncating mutations in trans were all associated with SMARD1. Conclusion This study provides evidence that the complete LOF mechanism of the IGHMBP2 gene defect may be an important cause of SMARD1.
Collapse
Affiliation(s)
- Yuan Tian
- Department of Clinical Laboratory, The Third Affiliated Hospital of Zhengzhou University, Zhengzhou, China
| | - Jinfang Xing
- Department of Clinical Laboratory, The Third Affiliated Hospital of Zhengzhou University, Zhengzhou, China
| | - Ying Shi
- Screening Center, The Third Affiliated Hospital of Zhengzhou University, Zhengzhou, China
| | - Enwu Yuan
- Department of Clinical Laboratory, The Third Affiliated Hospital of Zhengzhou University, Zhengzhou, China
| |
Collapse
|
7
|
Vadla GP, Ricardez Hernandez SM, Mao J, Garro-Kacher MO, Lorson ZC, Rice RP, Hansen SA, Lorson CL, Singh K, Lorson MA. ABT1 modifies SMARD1 pathology via interactions with IGHMBP2 and stimulation of ATPase and helicase activity. JCI Insight 2023; 8:e164608. [PMID: 36480289 PMCID: PMC9977310 DOI: 10.1172/jci.insight.164608] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2022] [Accepted: 12/07/2022] [Indexed: 12/13/2022] Open
Abstract
SMA with respiratory distress type 1 (SMARD1) and Charcot-Marie-Tooth type 2S (CMT2S) are results of mutations in immunoglobulin mu DNA binding protein 2 (IGHMBP2). IGHMBP2 is a UPF1-like helicase with proposed roles in several cellular processes, including translation. This study examines activator of basal transcription 1 (ABT1), a modifier of SMARD1-nmd disease pathology. Microscale thermophoresis and dynamic light scattering demonstrate that IGHMBP2 and ABT1 proteins directly interact with high affinity. The association of ABT1 with IGHMBP2 significantly increases the ATPase and helicase activity as well as the processivity of IGHMBP2. The IGHMBP2/ABT1 complex interacts with the 47S pre-rRNA 5' external transcribed spacer and U3 small nucleolar RNA (snoRNA), suggesting that the IGHMBP2/ABT1 complex is important for pre-rRNA processing. Intracerebroventricular injection of scAAV9-Abt1 decreases FVB-Ighmbp2nmd/nmd disease pathology, significantly increases lifespan, and substantially decreases neuromuscular junction denervation. To our knowledge, ABT1 is the first disease-modifying gene identified for SMARD1. We provide a mechanism proposing that ABT1 decreases disease pathology in FVB-Ighmbp2nmd/nmd mutants by optimizing IGHMBP2 biochemical activity (ATPase and helicase activity). Our studies provide insight into SMARD1 pathogenesis, suggesting that ABT1 modifies IGHMBP2 activity as a means to regulate pre-rRNA processing.
Collapse
Affiliation(s)
- Gangadhar P. Vadla
- Department of Veterinary Pathobiology, College of Veterinary Medicine, and
- Bond Life Sciences Center, University of Missouri, Columbia, Missouri, USA
| | - Sara M. Ricardez Hernandez
- Department of Veterinary Pathobiology, College of Veterinary Medicine, and
- Bond Life Sciences Center, University of Missouri, Columbia, Missouri, USA
| | - Jiude Mao
- Department of Veterinary Pathobiology, College of Veterinary Medicine, and
- Bond Life Sciences Center, University of Missouri, Columbia, Missouri, USA
| | - Mona O. Garro-Kacher
- Department of Veterinary Pathobiology, College of Veterinary Medicine, and
- Bond Life Sciences Center, University of Missouri, Columbia, Missouri, USA
| | - Zachary C. Lorson
- Department of Veterinary Pathobiology, College of Veterinary Medicine, and
- Bond Life Sciences Center, University of Missouri, Columbia, Missouri, USA
| | - Ronin P. Rice
- Department of Veterinary Pathobiology, College of Veterinary Medicine, and
- Bond Life Sciences Center, University of Missouri, Columbia, Missouri, USA
| | - Sarah A. Hansen
- Bond Life Sciences Center, University of Missouri, Columbia, Missouri, USA
| | - Christian L. Lorson
- Department of Veterinary Pathobiology, College of Veterinary Medicine, and
- Bond Life Sciences Center, University of Missouri, Columbia, Missouri, USA
| | - Kamal Singh
- Department of Veterinary Pathobiology, College of Veterinary Medicine, and
- Bond Life Sciences Center, University of Missouri, Columbia, Missouri, USA
| | - Monique A. Lorson
- Department of Veterinary Pathobiology, College of Veterinary Medicine, and
- Bond Life Sciences Center, University of Missouri, Columbia, Missouri, USA
| |
Collapse
|
8
|
Abstract
Spinal muscular atrophy (SMA) is caused by biallelic mutations in the SMN1 (survival motor neuron 1) gene on chromosome 5q13.2, which leads to a progressive degeneration of alpha motor neurons in the spinal cord and in motor nerve nuclei in the caudal brainstem. It is characterized by progressive proximally accentuated muscle weakness with loss of already acquired motor skills, areflexia and, depending on the phenotype, varying degrees of weakness of the respiratory and bulbar muscles. Over the past decade, disease-modifying therapies have become available based on splicing modulation of the SMN2 with SMN1 gene replacement, which if initiated significantly modifies the natural course of the disease. Newborn screening for SMA has been implemented in an increasing number of centers; however, available evidence for these new treatments is often limited to a small spectrum of patients concerning age and disease stage.
Collapse
Affiliation(s)
- David S Younger
- Department of Clinical Medicine and Neuroscience, CUNY School of Medicine, New York, NY, United States; Department of Medicine, Section of Internal Medicine and Neurology, White Plains Hospital, White Plains, NY, United States.
| | - Jerry R Mendell
- Department of Neurology and Pediatrics, Center for Gene Therapy, Abigail Wexner Research Institute, The Ohio State University, Nationwide Children's Hospital, Columbus, OH, United States
| |
Collapse
|
9
|
Younger DS. Neurogenetic motor disorders. HANDBOOK OF CLINICAL NEUROLOGY 2023; 195:183-250. [PMID: 37562870 DOI: 10.1016/b978-0-323-98818-6.00003-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/12/2023]
Abstract
Advances in the field of neurogenetics have practical applications in rapid diagnosis on blood and body fluids to extract DNA, obviating the need for invasive investigations. The ability to obtain a presymptomatic diagnosis through genetic screening and biomarkers can be a guide to life-saving disease-modifying therapy or enzyme replacement therapy to compensate for the deficient disease-causing enzyme. The benefits of a comprehensive neurogenetic evaluation extend to family members in whom identification of the causal gene defect ensures carrier detection and at-risk counseling for future generations. This chapter explores the many facets of the neurogenetic evaluation in adult and pediatric motor disorders as a primer for later chapters in this volume and a roadmap for the future applications of genetics in neurology.
Collapse
Affiliation(s)
- David S Younger
- Department of Clinical Medicine and Neuroscience, CUNY School of Medicine, New York, NY, United States; Department of Medicine, Section of Internal Medicine and Neurology, White Plains Hospital, White Plains, NY, United States.
| |
Collapse
|
10
|
Rzepnikowska W, Kaminska J, Kochański A. Validation of the Pathogenic Effect of IGHMBP2 Gene Mutations Based on Yeast S. cerevisiae Model. Int J Mol Sci 2022; 23:ijms23179913. [PMID: 36077311 PMCID: PMC9456350 DOI: 10.3390/ijms23179913] [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: 07/26/2022] [Revised: 08/28/2022] [Accepted: 08/29/2022] [Indexed: 11/29/2022] Open
Abstract
Spinal muscular atrophy with respiratory distress type 1 (SMARD1) is a heritable neurodegenerative disease characterized by rapid respiratory failure within the first months of life and progressive muscle weakness and wasting. Although the causative gene, IGHMBP2, is well defined, information on IGHMBP2 mutations is not always sufficient to diagnose particular patients, as the gene is highly polymorphic and the pathogenicity of many gene variants is unknown. In this study, we generated a simple yeast model to establish the significance of IGHMBP2 variants for disease development, especially those that are missense mutations. We have shown that cDNA of the human gene encodes protein which is functional in yeast cells and different pathogenic mutations affect this functionality. Furthermore, there is a correlation between the phenotype estimated in in vitro studies and our results, indicating that our model may be used to quickly and simply distinguish between pathogenic and non-pathogenic mutations identified in IGHMBP2 in patients.
Collapse
Affiliation(s)
- Weronika Rzepnikowska
- Neuromuscular Unit, Mossakowski Medical Research Institute, Polish Academy of Sciences, 02-106 Warsaw, Poland
| | - Joanna Kaminska
- Institute of Biochemistry and Biophysics Polish Academy of Sciences, 02-106 Warsaw, Poland
- Correspondence:
| | - Andrzej Kochański
- Neuromuscular Unit, Mossakowski Medical Research Institute, Polish Academy of Sciences, 02-106 Warsaw, Poland
| |
Collapse
|
11
|
Silksmith B, Munot P, Starling L, Pujar S, Matthews E. Accelerating the genetic diagnosis of neurological disorders presenting with episodic apnoea in infancy. THE LANCET. CHILD & ADOLESCENT HEALTH 2022; 6:495-508. [PMID: 35525254 DOI: 10.1016/s2352-4642(22)00091-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/12/2022] [Revised: 02/25/2022] [Accepted: 03/03/2022] [Indexed: 11/26/2022]
Abstract
Unexplained episodic apnoea in infants (aged ≤1 year), including recurrent brief (<1 min) resolved unexplained events (known as BRUE), can be a diagnostic challenge. Recurrent unexplained apnoea might suggest a persistent, debilitating, and potentially fatal disorder. Genetic diseases are prevalent among this group, particularly in those who present with paroxysmal or episodic neurological symptoms. These disorders are individually rare and challenging for a general paediatrician to recognise, and there is often a delayed or even posthumous diagnosis (sometimes only made in retrospect when a second sibling becomes unwell). The disorders can be debilitating if untreated but pharmacotherapies are available for the vast majority. That any child should suffer from unnecessary morbidity or die from one of these disorders without a diagnosis or treatment having been offered is a tragedy; therefore, there is an urgent need to simplify and expedite the diagnostic journey. We propose an apnoea gene panel for hospital specialists caring for any infant who has recurrent apnoea without an obvious cause. This approach could remove the need to identify individual rare conditions, speed up diagnosis, and improve access to therapy, with the ultimate aim of reducing morbidity and mortality.
Collapse
Affiliation(s)
- Bryony Silksmith
- Department of Neurology, Great Ormond Street Hospital for Children NHS Foundation Trust, London, UK
| | - Pinki Munot
- Dubowitz Neuromuscular Centre, Great Ormond Street Hospital for Children NHS Foundation Trust, London, UK
| | - Luke Starling
- Centre for Inherited Cardiovascular Diseases, Great Ormond Street Hospital for Children NHS Foundation Trust, London, UK
| | - Suresh Pujar
- Department of Neurology, Great Ormond Street Hospital for Children NHS Foundation Trust, London, UK
| | - Emma Matthews
- Atkinson-Morley Neuromuscular Centre, Department of Neurology, St George's University Hospitals NHS Foundation Trust, London, UK; Molecular and Clinical Sciences Research Institute, St George's University of London, London, UK.
| |
Collapse
|
12
|
Smith CE, Lorson MA, Ricardez Hernandez SM, Al Rawi Z, Mao J, Marquez J, Villalón E, Keilholz AN, Smith CL, Garro-Kacher MO, Morcos T, Davis DJ, Bryda EC, Nichols NL, Lorson CL. The Ighmbp2D564N mouse model is the first SMARD1 model to demonstrate respiratory defects. Hum Mol Genet 2022; 31:1293-1307. [PMID: 34726235 PMCID: PMC9029233 DOI: 10.1093/hmg/ddab317] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2021] [Revised: 09/30/2021] [Accepted: 10/26/2021] [Indexed: 11/12/2022] Open
Abstract
Spinal muscular atrophy with respiratory distress type I (SMARD1) is a neurodegenerative disease defined by respiratory distress, muscle atrophy and sensory and autonomic nervous system defects. SMARD1 is a result of mutations within the IGHMBP2 gene. We have generated six Ighmbp2 mouse models based on patient-derived mutations that result in SMARD1 and/or Charcot-Marie Tooth Type 2 (CMT2S). Here we describe the characterization of one of these models, Ighmbp2D564N (human D565N). The Ighmbp2D564N/D564N mouse model mimics important aspects of the SMARD1 disease phenotype, including motor neuron degeneration and muscle atrophy. Ighmbp2D564N/D564N is the first SMARD1 mouse model to demonstrate respiratory defects based on quantified plethysmography analyses. SMARD1 disease phenotypes, including the respiratory defects, are significantly diminished by intracerebroventricular (ICV) injection of ssAAV9-IGHMBP2 and the extent of phenotypic restoration is dose-dependent. Collectively, this model provides important biological insight into SMARD1 disease development.
Collapse
Affiliation(s)
- Caley E Smith
- Department of Veterinary Pathobiology, College of Veterinary Medicine, University of Missouri, Columbia, MO 65211, USA
- Bond Life Sciences Center, University of Missouri, Columbia, MO 65211, USA
| | - Monique A Lorson
- Department of Veterinary Pathobiology, College of Veterinary Medicine, University of Missouri, Columbia, MO 65211, USA
- Bond Life Sciences Center, University of Missouri, Columbia, MO 65211, USA
| | - Sara M Ricardez Hernandez
- Department of Veterinary Pathobiology, College of Veterinary Medicine, University of Missouri, Columbia, MO 65211, USA
- Bond Life Sciences Center, University of Missouri, Columbia, MO 65211, USA
| | - Zayd Al Rawi
- Department of Veterinary Pathobiology, College of Veterinary Medicine, University of Missouri, Columbia, MO 65211, USA
- Bond Life Sciences Center, University of Missouri, Columbia, MO 65211, USA
| | - Jiude Mao
- Department of Veterinary Pathobiology, College of Veterinary Medicine, University of Missouri, Columbia, MO 65211, USA
- Bond Life Sciences Center, University of Missouri, Columbia, MO 65211, USA
| | - Jose Marquez
- Department of Veterinary Pathobiology, College of Veterinary Medicine, University of Missouri, Columbia, MO 65211, USA
- Bond Life Sciences Center, University of Missouri, Columbia, MO 65211, USA
| | - Eric Villalón
- Department of Veterinary Pathobiology, College of Veterinary Medicine, University of Missouri, Columbia, MO 65211, USA
- Bond Life Sciences Center, University of Missouri, Columbia, MO 65211, USA
| | - Amy N Keilholz
- Department of Biomedical Sciences, College of Veterinary Medicine, University of Missouri, Columbia, MO 65211, USA
| | - Catherine L Smith
- Department of Biomedical Sciences, College of Veterinary Medicine, University of Missouri, Columbia, MO 65211, USA
| | - Mona O Garro-Kacher
- Department of Veterinary Pathobiology, College of Veterinary Medicine, University of Missouri, Columbia, MO 65211, USA
- Bond Life Sciences Center, University of Missouri, Columbia, MO 65211, USA
| | - Toni Morcos
- Department of Veterinary Pathobiology, College of Veterinary Medicine, University of Missouri, Columbia, MO 65211, USA
- Bond Life Sciences Center, University of Missouri, Columbia, MO 65211, USA
| | - Daniel J Davis
- Animal Modeling Core, University of Missouri, Columbia, MO 65211, USA
| | - Elizabeth C Bryda
- Department of Veterinary Pathobiology, College of Veterinary Medicine, University of Missouri, Columbia, MO 65211, USA
- Animal Modeling Core, University of Missouri, Columbia, MO 65211, USA
| | - Nicole L Nichols
- Department of Biomedical Sciences, College of Veterinary Medicine, University of Missouri, Columbia, MO 65211, USA
| | - Christian L Lorson
- Department of Veterinary Pathobiology, College of Veterinary Medicine, University of Missouri, Columbia, MO 65211, USA
- Bond Life Sciences Center, University of Missouri, Columbia, MO 65211, USA
| |
Collapse
|
13
|
Stembalska A, Rydzanicz M, Walas W, Gasperowicz P, Pollak A, Pienkowski VM, Biela M, Klaniewska M, Gamrot Z, Gronska E, Ploski R, Smigiel R. Severe Infantile Axonal Neuropathy with Respiratory Failure Caused by Novel Mutation in X-Linked LAS1L Gene. Genes (Basel) 2022; 13:genes13050725. [PMID: 35627110 PMCID: PMC9142081 DOI: 10.3390/genes13050725] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2022] [Revised: 04/11/2022] [Accepted: 04/19/2022] [Indexed: 12/10/2022] Open
Abstract
LAS1L encodes a nucleolar ribosomal biogenesis protein and is also a component of the Five Friends of Methylated CHTOP (5FMC) complex. Mutations in the LAS1L gene can be associated with Wilson−Turner syndrome (WTS) and, much more rarely, severe infantile hypotonia with respiratory failure. Here, we present an eighteen-month old boy with a phenotype of spinal muscular atrophy with respiratory distress (SMARD). By applying WES, we identified a novel hemizygous synonymous variant in the LAS1L gene inherited from an unaffected mother (c.846G > C, p.Thr282=). We suggest that the identified variant impairs the RNA splicing process. Furthermore, we proved the absence of any coding regions by qPCR and sequencing cDNA using amplicon deep sequencing and Sanger sequencing methods. According to the SMARD phenotype, severe breathing problems causing respiratory insufficiency, hypotonia, and feeding difficulties were observed in our patient from the first days of life. Remarkably, our case is the second described patient with a SMARD-like phenotype due to a mutation in the LAS1L gene and the first with a variant impacting splicing.
Collapse
Affiliation(s)
| | - Małgorzata Rydzanicz
- Department of Medical Genetics, Medical University of Warsaw, 02-106 Warsaw, Poland; (P.G.); (A.P.); (V.M.P.); (R.P.)
- Correspondence: (M.R.); (R.S.)
| | - Wojciech Walas
- Paediatric and Neonatal Intensive Care Unit, University Hospital in Opole, 45-401 Opole, Poland;
| | - Piotr Gasperowicz
- Department of Medical Genetics, Medical University of Warsaw, 02-106 Warsaw, Poland; (P.G.); (A.P.); (V.M.P.); (R.P.)
| | - Agnieszka Pollak
- Department of Medical Genetics, Medical University of Warsaw, 02-106 Warsaw, Poland; (P.G.); (A.P.); (V.M.P.); (R.P.)
| | - Victor Murcia Pienkowski
- Department of Medical Genetics, Medical University of Warsaw, 02-106 Warsaw, Poland; (P.G.); (A.P.); (V.M.P.); (R.P.)
- MMG, Marseille Medical Genetics U1251, Aix Marseille University, 13385 Marseille, France
| | - Mateusz Biela
- Department of Family and Paediatric Nursing, Medical University, 50-996 Wroclaw, Poland; (M.B.); (M.K.)
| | - Magdalena Klaniewska
- Department of Family and Paediatric Nursing, Medical University, 50-996 Wroclaw, Poland; (M.B.); (M.K.)
| | - Zuzanna Gamrot
- Care and Therapy Unit for Mechanically Ventilated Children and Young People, 41-506 Chorzow, Poland; (Z.G.); (E.G.)
| | - Ewa Gronska
- Care and Therapy Unit for Mechanically Ventilated Children and Young People, 41-506 Chorzow, Poland; (Z.G.); (E.G.)
| | - Rafal Ploski
- Department of Medical Genetics, Medical University of Warsaw, 02-106 Warsaw, Poland; (P.G.); (A.P.); (V.M.P.); (R.P.)
| | - Robert Smigiel
- Department of Family and Paediatric Nursing, Medical University, 50-996 Wroclaw, Poland; (M.B.); (M.K.)
- Correspondence: (M.R.); (R.S.)
| |
Collapse
|
14
|
Jablonka S, Hennlein L, Sendtner M. Therapy development for spinal muscular atrophy: perspectives for muscular dystrophies and neurodegenerative disorders. Neurol Res Pract 2022; 4:2. [PMID: 34983696 PMCID: PMC8725368 DOI: 10.1186/s42466-021-00162-9] [Citation(s) in RCA: 19] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2021] [Accepted: 10/21/2021] [Indexed: 12/26/2022] Open
Abstract
BACKGROUND Major efforts have been made in the last decade to develop and improve therapies for proximal spinal muscular atrophy (SMA). The introduction of Nusinersen/Spinraza™ as an antisense oligonucleotide therapy, Onasemnogene abeparvovec/Zolgensma™ as an AAV9-based gene therapy and Risdiplam/Evrysdi™ as a small molecule modifier of pre-mRNA splicing have set new standards for interference with neurodegeneration. MAIN BODY Therapies for SMA are designed to interfere with the cellular basis of the disease by modifying pre-mRNA splicing and enhancing expression of the Survival Motor Neuron (SMN) protein, which is only expressed at low levels in this disorder. The corresponding strategies also can be applied to other disease mechanisms caused by loss of function or toxic gain of function mutations. The development of therapies for SMA was based on the use of cell culture systems and mouse models, as well as innovative clinical trials that included readouts that had originally been introduced and optimized in preclinical studies. This is summarized in the first part of this review. The second part discusses current developments and perspectives for amyotrophic lateral sclerosis, muscular dystrophies, Parkinson's and Alzheimer's disease, as well as the obstacles that need to be overcome to introduce RNA-based therapies and gene therapies for these disorders. CONCLUSION RNA-based therapies offer chances for therapy development of complex neurodegenerative disorders such as amyotrophic lateral sclerosis, muscular dystrophies, Parkinson's and Alzheimer's disease. The experiences made with these new drugs for SMA, and also the experiences in AAV gene therapies could help to broaden the spectrum of current approaches to interfere with pathophysiological mechanisms in neurodegeneration.
Collapse
Affiliation(s)
- Sibylle Jablonka
- Institute of Clinical Neurobiology, University Hospital of Wuerzburg, Versbacher Str. 5, 97078, Wuerzburg, Germany.
| | - Luisa Hennlein
- Institute of Clinical Neurobiology, University Hospital of Wuerzburg, Versbacher Str. 5, 97078, Wuerzburg, Germany
| | - Michael Sendtner
- Institute of Clinical Neurobiology, University Hospital of Wuerzburg, Versbacher Str. 5, 97078, Wuerzburg, Germany.
| |
Collapse
|
15
|
Shababi M, Smith CE, Ricardez Hernandez SM, Marquez J, Al Rawi Z, Villalón E, Farris KD, Garro-Kacher MO, Lorson CL. Defining the optimal dose and therapeutic window in SMA with respiratory distress type I model mice, FVB/NJ- Ighmpb2 nmd-2J. Mol Ther Methods Clin Dev 2021; 23:23-32. [PMID: 34553000 PMCID: PMC8426477 DOI: 10.1016/j.omtm.2021.07.008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2021] [Accepted: 07/30/2021] [Indexed: 11/23/2022]
Abstract
Spinal muscular atrophy with respiratory distress type 1 (SMARD1) is an autosomal recessive disorder that develops in infancy and arises from mutation of the immunoglobulin helicase μ-binding protein 2 (IGHMBP2) gene. Whereas IGHMBP2 is ubiquitously expressed, loss or reduction of function leads to alpha motor neuron loss and skeletal muscle atrophy. We previously developed a gene therapy strategy for SMARD1 using a single-stranded AAV9-IGHMBP2 vector and compared two different delivery methods in a validated SMARD1 mouse model. An important question in the field relates to the temporal requirements for this or any potential treatment. To examine the therapeutic window, we utilized our recently developed SMARD1 model, FVB/NJ-Ighmpb2 nmd-2J , to deliver AAV9-IGHMBP2 at four different time points starting at post-natal day 2 (P2) through P8. At each time point, significant improvements were observed in survival, weight gain, and motor function. Similarly, treatment improved important hallmarks of disease, including motor unit pathology. Whereas improvements were more pronounced in the early-treatment groups, even the later-treatment groups displayed significant phenotypic improvements. This work suggests that an effective gene therapy strategy could provide benefits to pre-symptomatic and early-symptomatic individuals, thereby expanding the potential therapeutic window for SMARD1.
Collapse
Affiliation(s)
- Monir Shababi
- Department of Veterinary Pathobiology, College of Veterinary Medicine, University of Missouri, Columbia, MO 65211, USA
- Bond Life Sciences Center, University of Missouri, Columbia, MO 65211, USA
| | - Caley E. Smith
- Bond Life Sciences Center, University of Missouri, Columbia, MO 65211, USA
| | | | - Jose Marquez
- Bond Life Sciences Center, University of Missouri, Columbia, MO 65211, USA
| | - Zayd Al Rawi
- Bond Life Sciences Center, University of Missouri, Columbia, MO 65211, USA
| | - Eric Villalón
- Bond Life Sciences Center, University of Missouri, Columbia, MO 65211, USA
| | - K. David Farris
- Department of Veterinary Pathobiology, College of Veterinary Medicine, University of Missouri, Columbia, MO 65211, USA
- Bond Life Sciences Center, University of Missouri, Columbia, MO 65211, USA
| | - Mona O. Garro-Kacher
- Department of Veterinary Pathobiology, College of Veterinary Medicine, University of Missouri, Columbia, MO 65211, USA
- Bond Life Sciences Center, University of Missouri, Columbia, MO 65211, USA
| | - Christian L. Lorson
- Department of Veterinary Pathobiology, College of Veterinary Medicine, University of Missouri, Columbia, MO 65211, USA
- Bond Life Sciences Center, University of Missouri, Columbia, MO 65211, USA
| |
Collapse
|
16
|
Rzepnikowska W, Kochański A. Models for IGHMBP2-associated diseases: an overview and a roadmap for the future. Neuromuscul Disord 2021; 31:1266-1278. [PMID: 34785121 DOI: 10.1016/j.nmd.2021.08.001] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2021] [Revised: 07/16/2021] [Accepted: 08/06/2021] [Indexed: 12/13/2022]
Abstract
Models are practical tools with which to establish the basic aspects of a diseases. They allow systematic research into the significance of mutations, of cellular and molecular pathomechanisms, of therapeutic options and of functions of diseases associated proteins. Thus, disease models are an integral part of the study of enigmatic proteins such as immunoglobulin mu-binding protein 2 (IGHMBP2). IGHMBP2 has been well defined as a helicase, however there is little known about its role in cellular processes. Notably, it is unclear why changes in such an abundant protein lead to specific neuronal disorders including spinal muscular atrophy with respiratory distress type 1 (SMARD1) and Charcot-Marie-Tooth type 2S (CMT2S). SMARD1 is caused by a loss of motor neurons in the spinal cord that results in muscle atrophy and is accompanied by rapid respiratory failure. In contrast, CMT2S manifests as a severe neuropathy, but typically without critical breathing problems. Here, we present the clinical manifestation of IGHMBP2 mutations, function of protein and models that may be used for the study of IGHMBP2-associated disorders. We highlight the strengths and weaknesses of specific models and discuss the orthologs of IGHMBP2 that are found in different systems with regard to their similarity to human IGHMBP2.
Collapse
Affiliation(s)
- Weronika Rzepnikowska
- Neuromuscular Unit, Mossakowski Medical Research Institute Polish Academy of Sciences, Warsaw 02-106, Poland.
| | - Andrzej Kochański
- Neuromuscular Unit, Mossakowski Medical Research Institute Polish Academy of Sciences, Warsaw 02-106, Poland
| |
Collapse
|
17
|
Suthar R, Bhagwat C, Paria P, Aggarwal D, Kumar N, Chatterjee D, Saini A, Angurana S, Sankhyan N. Early infantile onset non-5q spinal muscular atrophies: A diagnostic odyssey. Ann Indian Acad Neurol 2021; 24:995-997. [PMID: 35359517 PMCID: PMC8965950 DOI: 10.4103/aian.aian_680_20] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2020] [Accepted: 07/02/2020] [Indexed: 11/09/2022] Open
|
18
|
Bodle EE, Zhu W, Velez-Bartolomei F, Tesi-Rocha A, Liu P, Bernstein JA. Combined Genome Sequencing and RNA Analysis Reveals and Characterizes a Deep Intronic Variant in IGHMBP2 in a Patient With Spinal Muscular Atrophy With Respiratory Distress Type 1. Pediatr Neurol 2021; 114:16-20. [PMID: 33189025 DOI: 10.1016/j.pediatrneurol.2020.09.011] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/13/2020] [Revised: 09/21/2020] [Accepted: 09/23/2020] [Indexed: 02/06/2023]
Abstract
BACKGROUND Pathogenic variants in the IGHMBP2 gene cause recessive spinal motor neuropathies of variable phenotype, including a predominantly distal motor impairment of Charcot-Marie-Tooth type 2S and the more severe condition of spinal muscular atrophy with respiratory distress type 1 in which infantile respiratory failure predominates. METHODS We describe the first reported case of spinal muscular atrophy with respiratory distress type 1 caused by a novel deep intronic variant in IGHMBP2 (NM_002180c.712-610A>G). RESULTS The variant was detected by whole genome sequencing. Reverse transcription-polymerase chain reaction and complimentary DNA sequencing were used to characterize the impact of the novel variant. CONCLUSIONS This report illustrates the utility in clinical practice of genome sequencing and RNA analysis, compared with exome sequencing alone.
Collapse
Affiliation(s)
- Ethan E Bodle
- Division of Medical Genetics, Department of Pediatrics, Stanford University School of Medicine, Stanford, California.
| | | | - Frances Velez-Bartolomei
- Division of Medical Genetics, Department of Pediatrics, Stanford University School of Medicine, Stanford, California
| | - Ana Tesi-Rocha
- Department of Neurology, Stanford University School of Medicine, Stanford, California
| | - Pengfei Liu
- Baylor Genetics, Houston, Texas; Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas
| | - Jonathan A Bernstein
- Division of Medical Genetics, Department of Pediatrics, Stanford University School of Medicine, Stanford, California
| |
Collapse
|
19
|
Perego MGL, Galli N, Nizzardo M, Govoni A, Taiana M, Bresolin N, Comi GP, Corti S. Current understanding of and emerging treatment options for spinal muscular atrophy with respiratory distress type 1 (SMARD1). Cell Mol Life Sci 2020; 77:3351-3367. [PMID: 32123965 PMCID: PMC11104977 DOI: 10.1007/s00018-020-03492-0] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2019] [Revised: 02/08/2020] [Accepted: 02/20/2020] [Indexed: 12/11/2022]
Abstract
Spinal muscular atrophy (SMA) with respiratory distress type 1 (SMARD1) is an autosomal recessive motor neuron disease that is characterized by distal and proximal muscle weakness and diaphragmatic palsy that leads to respiratory distress. Without intervention, infants with the severe form of the disease die before 2 years of age. SMARD1 is caused by mutations in the IGHMBP2 gene that determine a deficiency in the encoded IGHMBP2 protein, which plays a critical role in motor neuron survival because of its functions in mRNA processing and maturation. Although it is rare, SMARD1 is the second most common motor neuron disease of infancy, and currently, treatment is primarily supportive. No effective therapy is available for this devastating disease, although multidisciplinary care has been an essential element of the improved quality of life and life span extension in these patients in recent years. The objectives of this review are to discuss the current understanding of SMARD1 through a summary of the presently known information regarding its clinical presentation and pathogenesis and to discuss emerging therapeutic approaches. Advances in clinical care management have significantly extended the lives of individuals affected by SMARD1 and research into the molecular mechanisms that lead to the disease has identified potential strategies for intervention that target the underlying causes of SMARD1. Gene therapy via gene replacement or gene correction provides the potential for transformative therapies to halt or possibly prevent neurodegenerative disease in SMARD1 patients. The recent approval of the first gene therapy approach for SMA associated with mutations in the SMN1 gene may be a turning point for the application of this strategy for SMARD1 and other genetic neurological diseases.
Collapse
Affiliation(s)
- Martina G L Perego
- Neuroscience Section, Department of Pathophysiology and Transplantation (DEPT), Dino Ferrari Centre, University of Milan, Via Francesco Sforza 35, 20122, Milan, Italy
| | - Noemi Galli
- Neuroscience Section, Department of Pathophysiology and Transplantation (DEPT), Dino Ferrari Centre, University of Milan, Via Francesco Sforza 35, 20122, Milan, Italy
| | - Monica Nizzardo
- Neurology Unit, Foundation IRCCS Ca' Granda Ospedale Maggiore Policlinico, Via Francesco Sforza 35, 20122, Milan, Italy
| | - Alessandra Govoni
- Neurology Unit, Foundation IRCCS Ca' Granda Ospedale Maggiore Policlinico, Via Francesco Sforza 35, 20122, Milan, Italy
| | - Michela Taiana
- Neurology Unit, Foundation IRCCS Ca' Granda Ospedale Maggiore Policlinico, Via Francesco Sforza 35, 20122, Milan, Italy
| | - Nereo Bresolin
- Neuroscience Section, Department of Pathophysiology and Transplantation (DEPT), Dino Ferrari Centre, University of Milan, Via Francesco Sforza 35, 20122, Milan, Italy
- Neurology Unit, Foundation IRCCS Ca' Granda Ospedale Maggiore Policlinico, Via Francesco Sforza 35, 20122, Milan, Italy
| | - Giacomo P Comi
- Neuroscience Section, Department of Pathophysiology and Transplantation (DEPT), Dino Ferrari Centre, University of Milan, Via Francesco Sforza 35, 20122, Milan, Italy
- Neuromuscular and Rare Diseases Unit, Foundation IRCCS Ca' Granda Ospedale Maggiore Policlinico, Via Francesco Sforza 35, 20122, Milan, Italy
| | - Stefania Corti
- Neuroscience Section, Department of Pathophysiology and Transplantation (DEPT), Dino Ferrari Centre, University of Milan, Via Francesco Sforza 35, 20122, Milan, Italy.
- Neurology Unit, Foundation IRCCS Ca' Granda Ospedale Maggiore Policlinico, Via Francesco Sforza 35, 20122, Milan, Italy.
| |
Collapse
|
20
|
Liu X, Duan X, Zhang Y, Sun A, Fan D. Molecular analysis and clinical diversity of distal hereditary motor neuropathy. Eur J Neurol 2020; 27:1319-1326. [PMID: 32298515 DOI: 10.1111/ene.14260] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2019] [Revised: 12/05/2019] [Accepted: 04/07/2020] [Indexed: 01/13/2023]
Abstract
BACKGROUND AND PURPOSE Distal hereditary motor neuropathies (dHMNs) are a clinically and genetically heterogeneous group of disorders. The purpose of this study was to identify the genetic distribution of dHMNs in a large cohort of Chinese patients and provide insight into the underlying common pathophysiology of dHMNs. METHODS Multi-gene panel testing or whole-exome sequencing was performed in 70 index patients with clinically diagnosed dHMN between January 2007 and December 2018. The clinical features, Charcot-Marie-Tooth (CMT) neuropathy scores and electrophysiological data at diagnosis were recorded. RESULTS Twenty-four causative mutations were identified in 70 index patients with dHMN (34.3%). Mutation in the HSPB1 gene was the most common cause of dHMN. Some CMT genes (MPZ, SH3TC2, GDAP1) were found to be related to dHMN with minor sensory involvement. Patients with a dHMN-plus phenotype (distal motor neuropathy and additional neurological deficits) carried variants in genes related to hereditary spastic paraplegia, amyotrophic lateral sclerosis and spinal muscular atrophy (FUS, KIF5A, KIF1B, ZFYVE26, DNAJB2). CONCLUSIONS Comprehensive genetic testing of dHMN patients allows for identification of the pathogenic mutation in one-third of cases. Pure motor neuropathies and motor neuropathies with minor sensory involvement share many genes with CMT disease. Causes for dHMN-plus phenotypes overlap with motor neuron disease.
Collapse
Affiliation(s)
- X Liu
- Department of Neurology, Peking University Third Hospital, Beijing, China.,Beijing Municipal Key Laboratory of Biomarker and Translational Research in Neurodegenerative Diseases, Beijing, China
| | - X Duan
- Department of Neurology, China-Japan Friendship Hospital, Beijing, China
| | - Y Zhang
- Department of Neurology, Peking University Third Hospital, Beijing, China.,Beijing Municipal Key Laboratory of Biomarker and Translational Research in Neurodegenerative Diseases, Beijing, China
| | - A Sun
- Department of Neurology, Peking University Third Hospital, Beijing, China.,Beijing Municipal Key Laboratory of Biomarker and Translational Research in Neurodegenerative Diseases, Beijing, China
| | - D Fan
- Department of Neurology, Peking University Third Hospital, Beijing, China.,Beijing Municipal Key Laboratory of Biomarker and Translational Research in Neurodegenerative Diseases, Beijing, China.,Key Laboratory for Neuroscience, National Health Commission/Ministry of Education, Peking University, Beijing, China
| |
Collapse
|
21
|
Martin PB, Hicks AN, Holbrook SE, Cox GA. Overlapping spectrums: The clinicogenetic commonalities between Charcot-Marie-Tooth and other neurodegenerative diseases. Brain Res 2020; 1727:146532. [PMID: 31678418 PMCID: PMC6939129 DOI: 10.1016/j.brainres.2019.146532] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2019] [Revised: 10/20/2019] [Accepted: 10/22/2019] [Indexed: 12/11/2022]
Abstract
Charcot-Marie-Tooth (CMT) disease is a progressive and heterogeneous inherited peripheral neuropathy. A myriad of genetic factors have been identified that contribute to the degeneration of motor and sensory axons in a length-dependent manner. Emerging biological themes underlying disease include defects in axonal trafficking, dysfunction in RNA metabolism and protein homeostasis, as well deficits in the cellular stress response. Moreover, genetic contributions to CMT can have overlap with other neuropathies, motor neuron diseases (MNDs) and neurodegenerative disorders. Recent progress in understanding the molecular biology of CMT and overlapping syndromes aids in the search for necessary therapeutic targets.
Collapse
Affiliation(s)
- Paige B Martin
- The Jackson Laboratory, Bar Harbor, ME 04609, USA; Graduate School of Biomedical Sciences and Engineering, University of Maine, Orono, ME 04469, USA
| | - Amy N Hicks
- The Jackson Laboratory, Bar Harbor, ME 04609, USA
| | - Sarah E Holbrook
- The Jackson Laboratory, Bar Harbor, ME 04609, USA; Graduate School of Biomedical Sciences and Engineering, University of Maine, Orono, ME 04469, USA
| | - Gregory A Cox
- The Jackson Laboratory, Bar Harbor, ME 04609, USA; Graduate School of Biomedical Sciences and Engineering, University of Maine, Orono, ME 04469, USA.
| |
Collapse
|
22
|
Saladini M, Nizzardo M, Govoni A, Taiana M, Bresolin N, Comi GP, Corti S. Spinal muscular atrophy with respiratory distress type 1: Clinical phenotypes, molecular pathogenesis and therapeutic insights. J Cell Mol Med 2019; 24:1169-1178. [PMID: 31802621 PMCID: PMC6991628 DOI: 10.1111/jcmm.14874] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2019] [Revised: 09/14/2019] [Accepted: 11/10/2019] [Indexed: 01/17/2023] Open
Abstract
Spinal muscular atrophy with respiratory distress type 1 (SMARD1) is a rare autosomal recessive neuromuscular disorder caused by mutations in the IGHMBP2 gene, which encodes immunoglobulin μ‐binding protein 2, leading to progressive spinal motor neuron degeneration. We review the data available in the literature about SMARD1. The vast majority of patients show an onset of typical symptoms in the first year of life. The main clinical features are distal muscular atrophy and diaphragmatic palsy, for which permanent supportive ventilation is required. No effective treatment is available yet, but novel therapeutic approaches, such as gene therapy, have shown encouraging results in preclinical settings and thus represent possible methods for treating SMARD1. Significant advancements in the understanding of both the SMARD1 clinical spectrum and its molecular mechanisms have allowed the rapid translation of preclinical therapeutic strategies to human patients to improve the poor prognosis of this devastating disease.
Collapse
Affiliation(s)
- Matteo Saladini
- Dino Ferrari Centre, Neuroscience Section, Department of Pathophysiology and Transplantation (DEPT), University of Milan, Milan, Italy
| | - Monica Nizzardo
- Foundation IRCCS Ca' Granda Ospedale Maggiore Policlinico, Neurology Unit, Milan, Italy
| | - Alessandra Govoni
- Foundation IRCCS Ca' Granda Ospedale Maggiore Policlinico, Neurology Unit, Milan, Italy
| | - Michela Taiana
- Foundation IRCCS Ca' Granda Ospedale Maggiore Policlinico, Neurology Unit, Milan, Italy
| | - Nereo Bresolin
- Dino Ferrari Centre, Neuroscience Section, Department of Pathophysiology and Transplantation (DEPT), University of Milan, Milan, Italy.,Foundation IRCCS Ca' Granda Ospedale Maggiore Policlinico, Neurology Unit, Milan, Italy
| | - Giacomo P Comi
- Dino Ferrari Centre, Neuroscience Section, Department of Pathophysiology and Transplantation (DEPT), University of Milan, Milan, Italy.,Foundation IRCCS Ca' Granda Ospedale Maggiore Policlinico, Neuromuscular and rare diseases unit, Milan, Italy
| | - Stefania Corti
- Dino Ferrari Centre, Neuroscience Section, Department of Pathophysiology and Transplantation (DEPT), University of Milan, Milan, Italy.,Foundation IRCCS Ca' Granda Ospedale Maggiore Policlinico, Neurology Unit, Milan, Italy
| |
Collapse
|
23
|
Shababi M, Smith CE, Kacher M, Alrawi Z, Villalon E, Davis D, Bryda EC, Lorson CL. Development of a novel severe mouse model of spinal muscular atrophy with respiratory distress type 1: FVB-nmd. Biochem Biophys Res Commun 2019; 520:341-346. [PMID: 31604525 PMCID: PMC6936219 DOI: 10.1016/j.bbrc.2019.10.032] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2019] [Accepted: 10/02/2019] [Indexed: 11/29/2022]
Abstract
Spinal Muscular Atrophy with Respiratory Distress type 1 (SMARD1) is an autosomal recessive disease that develops early during infancy. The gene responsible for disease development is immunoglobulin helicase μ-binding protein 2 (IGHMBP2). IGHMBP2 is a ubiquitously expressed gene but its mutation results in the loss of alpha-motor neurons and subsequent muscle atrophy initially of distal muscles. The current SMARD1 mouse model arose from a spontaneous mutation originally referred to as neuromuscular degeneration (nmd). The nmd mice have the C57BL/6 genetic background and contain an A to G mutation in intron 4 of the endogenous Ighmbp2 gene. This mutation causes aberrant splicing, resulting in only 20-25% of full-length functional protein. Several congenital conditions including hydrocephalus are common in the C57BL/6 background, consistent with our previous observations when developing a gene therapy approach for SMARD1. Additionally, a modifier allele exists on chromosome 13 in nmd mice that can partially suppress the phenotype, resulting in some animals that have extended life spans (up to 200 days). To eliminate the intrinsic complications of the C57BL/6 background and the variation in survival due to the genetic modifier effect, we created a new SMARD1 mouse model that contains the same intron 4 mutation in Ighmbp2 as nmd mice but is now on a FVB congenic background. FVB-nmd are consistently more severe than the original nmd mice with respect to survival, weigh and motor function. The relatively short life span (18-21 days) of FVB-nmd mice allows us to monitor therapeutic efficacy for a variety of novel therapeutics in a timely manner without the complication of the small percentage of longer-lived animals that were observed in our colony of nmd mice.
Collapse
Affiliation(s)
- Monir Shababi
- Department of Veterinary Pathobiology, College of Veterinary Medicine, University of Missouri, Columbia, Missouri, USA,Christopher S. Bond Life Sciences Center, University of Missouri, Columbia, Missouri, USA
| | - Caley E. Smith
- Christopher S. Bond Life Sciences Center, University of Missouri, Columbia, Missouri, USA,Department of Molecular Microbiology and Immunology, University of Missouri School of Medicine, Columbia, Missouri, USA
| | - Mona Kacher
- Department of Veterinary Pathobiology, College of Veterinary Medicine, University of Missouri, Columbia, Missouri, USA,Christopher S. Bond Life Sciences Center, University of Missouri, Columbia, Missouri, USA
| | - Zayd Alrawi
- Christopher S. Bond Life Sciences Center, University of Missouri, Columbia, Missouri, USA
| | - Eric Villalon
- Department of Veterinary Pathobiology, College of Veterinary Medicine, University of Missouri, Columbia, Missouri, USA,Christopher S. Bond Life Sciences Center, University of Missouri, Columbia, Missouri, USA
| | - Daniel Davis
- Animal Modeling Core, University of Missouri, Columbia, Missouri, USA
| | - Elizabeth C. Bryda
- Department of Veterinary Pathobiology, College of Veterinary Medicine, University of Missouri, Columbia, Missouri, USA,Animal Modeling Core, University of Missouri, Columbia, Missouri, USA
| | - Christian L. Lorson
- Department of Veterinary Pathobiology, College of Veterinary Medicine, University of Missouri, Columbia, Missouri, USA,Christopher S. Bond Life Sciences Center, University of Missouri, Columbia, Missouri, USA,Department of Molecular Microbiology and Immunology, University of Missouri School of Medicine, Columbia, Missouri, USA
| |
Collapse
|
24
|
Villalón E, Lee NN, Marquez J, Lorson CL. Muscle fiber-type selective propensity to pathology in the nmd mouse model of SMARD1. Biochem Biophys Res Commun 2019; 516:313-319. [PMID: 31256932 DOI: 10.1016/j.bbrc.2019.06.117] [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: 06/11/2019] [Accepted: 06/21/2019] [Indexed: 12/01/2022]
Abstract
Spinal muscular atrophy with respiratory distress type 1 (SMARD1) is an autosomal recessive disease that causes distal limb muscle atrophy, due to motor neuron degeneration. Similar to other motor neuron diseases, SMARD1 shows differential vulnerability to denervation in various muscle groups, which is recapitulated in the nmd mouse, a model of SMARD1. In multiple neurodegenerative disease models, transcriptomic analysis has identified differentially expressed genes between vulnerable motor neuron populations, but the mechanism leading to susceptibility is largely unknown. To investigate if denervation vulnerability is linked to intrinsic muscle properties, we analyzed muscle fiber-type composition in muscles from motor units that show different degrees of denervation in nmd mice: gastrocnemius, tibialis anterior (TA), and extensor digitorum longus (EDL). Our results revealed that denervation vulnerability correlated with atrophy and loss of MyHC-IIb and MyHC-IIx muscle fiber types. Interestingly, increased vulnerability also correlated with an increased abundance of MyHC-I and MyHC-IIa muscle fibers. These results indicated that MyHC-IIx muscle fibers are the most vulnerable to denervation, followed by MyHC-IIb muscle fibers. Moreover, our data indicate that type MyHC-IIa and MyHC-IIb muscle fibers show resistance to denervation and compensate for the loss of MyHC-IIx and MyHC-IIb muscle fibers in the most vulnerable muscles. Taken together these results provide a basis for the selective vulnerability to denervation of specific muscles in nmd mice and identifies new targets for potential therapeutic intervention.
Collapse
Affiliation(s)
- Eric Villalón
- Bond Life Sciences Center, University of Missouri, Columbia, MO, 65211, USA; Department of Veterinary Pathobiology, College of Veterinary Medicine, University of Missouri, Columbia, MO, 65211, USA
| | - Naomi N Lee
- Department of Veterinary Pathobiology, College of Veterinary Medicine, University of Missouri, Columbia, MO, 65211, USA
| | - Jose Marquez
- Bond Life Sciences Center, University of Missouri, Columbia, MO, 65211, USA; Department of Veterinary Pathobiology, College of Veterinary Medicine, University of Missouri, Columbia, MO, 65211, USA
| | - Christian L Lorson
- Bond Life Sciences Center, University of Missouri, Columbia, MO, 65211, USA; Department of Veterinary Pathobiology, College of Veterinary Medicine, University of Missouri, Columbia, MO, 65211, USA.
| |
Collapse
|
25
|
Spinal muscular atrophy with respiratory distress type 1: A multicenter retrospective study. Neuromuscul Disord 2019; 29:114-126. [DOI: 10.1016/j.nmd.2018.10.002] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2018] [Revised: 08/14/2018] [Accepted: 10/25/2018] [Indexed: 12/14/2022]
|
26
|
Villalón E, Shababi M, Kline R, Lorson ZC, Florea KM, Lorson CL. Selective vulnerability in neuronal populations in nmd/SMARD1 mice. Hum Mol Genet 2019; 27:679-690. [PMID: 29272405 DOI: 10.1093/hmg/ddx434] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2017] [Accepted: 12/15/2017] [Indexed: 12/12/2022] Open
Abstract
Spinal muscular atrophy with respiratory distress type 1 (SMARD1) is an autosomal recessive motor neuron disease causing distal limb muscle atrophy that progresses proximally and is accompanied by diaphragmatic paralysis. Neuromuscular junction (NMJ) alterations have been reported in muscles of SMARD1 model mice, known as nmd mice, with varying degrees of severity, suggesting that different muscles are specifically and selectively resistant or susceptible to denervation. To evaluate the extent of NMJ pathology in a broad range of muscles, a panel of axial and appendicular muscles were isolated and immunostained from nmd mice. These analyses revealed that selective distal appendage muscles were highly vulnerable to denervation. Susceptibility to pathology was not limited to NMJ alterations, but included defects in myelination within those neurons innervating susceptible muscles. Interestingly, end plate fragmentation was present within all muscles independent of the extent of NMJ alterations, suggesting that end plate fragmentation is an early hallmark of SMARD1 pathogenesis. Expressing the full-length IGHMBP2 cDNA using an adeno-associated virus (AAV9) significantly decreased all aspects of muscle and nerve disease pathology. These results shed new light onto the pathogenesis of SMARD1 by identifying specific motor units that are resistant and susceptible to neurodegeneration in an important model of SMARD1.
Collapse
Affiliation(s)
- Eric Villalón
- Department of Veterinary Pathobiology, Christopher S. Bond Life Sciences Center, University of Missouri, Columbia, MO 65211, USA.,Department of Veterinary Pathobiology, College of Veterinary Medicine, University of Missouri, Columbia, MO 65211, USA
| | - Monir Shababi
- Department of Veterinary Pathobiology, Christopher S. Bond Life Sciences Center, University of Missouri, Columbia, MO 65211, USA.,Department of Veterinary Pathobiology, College of Veterinary Medicine, University of Missouri, Columbia, MO 65211, USA
| | - Rachel Kline
- Department of Veterinary Pathobiology, Christopher S. Bond Life Sciences Center, University of Missouri, Columbia, MO 65211, USA.,Department of Veterinary Pathobiology, College of Veterinary Medicine, University of Missouri, Columbia, MO 65211, USA
| | - Zachary C Lorson
- Department of Veterinary Pathobiology, Christopher S. Bond Life Sciences Center, University of Missouri, Columbia, MO 65211, USA.,Department of Veterinary Pathobiology, College of Veterinary Medicine, University of Missouri, Columbia, MO 65211, USA
| | - Kyra M Florea
- Department of Veterinary Pathobiology, Christopher S. Bond Life Sciences Center, University of Missouri, Columbia, MO 65211, USA.,Department of Veterinary Pathobiology, College of Veterinary Medicine, University of Missouri, Columbia, MO 65211, USA
| | - Christian L Lorson
- Department of Veterinary Pathobiology, Christopher S. Bond Life Sciences Center, University of Missouri, Columbia, MO 65211, USA.,Department of Veterinary Pathobiology, College of Veterinary Medicine, University of Missouri, Columbia, MO 65211, USA
| |
Collapse
|
27
|
Andrews JA, Shefner JM. Clinical neurophysiology of anterior horn cell disorders. HANDBOOK OF CLINICAL NEUROLOGY 2019; 161:317-326. [PMID: 31307610 DOI: 10.1016/b978-0-444-64142-7.00057-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
The development of neurophysiological techniques for clinical assessment in the 20th century is closely related to the study of anterior horn cell diseases. The effects of motor axon loss on nerve conduction velocity and compound motor amplitude were elucidated first in amyotrophic lateral sclerosis (ALS), as was the characterization of reinnervation as detected by needle electromyography. The same changes noted in early studies still play a major role in the diagnosis of anterior horn cell diseases. In addition, much of modern neurophysiological assessment of motor axon quantitation, ion channel changes in neurogenic disease, and cortical physiology studies to assess both network and excitability abnormalities have all been applied to ALS. In this chapter, we summarize the clinical attributes of ALS and Spinal Muscular Atrophy, and review how clinical neurophysiology is employed in the clinical and the research setting.
Collapse
Affiliation(s)
- Jinsy A Andrews
- The Neurological Institute, Columbia University, New York, NY, United States
| | - Jeremy M Shefner
- Department of Neurology, Barrow Neurological Institute, Phoenix, AZ, United States.
| |
Collapse
|
28
|
D’Amico A, Bertini E. Neonatal Hypotonia. Neurology 2019. [DOI: 10.1016/b978-0-323-54392-7.00013-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
|
29
|
Castiglioni C, Lozano-Arango A. Atrofias musculares espinales no asociadas a SMN1. REVISTA MÉDICA CLÍNICA LAS CONDES 2018. [DOI: 10.1016/j.rmclc.2018.10.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
|
30
|
Shababi M, Villalón E, Kaifer KA, DeMarco V, Lorson CL. A Direct Comparison of IV and ICV Delivery Methods for Gene Replacement Therapy in a Mouse Model of SMARD1. MOLECULAR THERAPY-METHODS & CLINICAL DEVELOPMENT 2018; 10:348-360. [PMID: 30202772 PMCID: PMC6127875 DOI: 10.1016/j.omtm.2018.08.005] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/08/2018] [Accepted: 08/13/2018] [Indexed: 01/22/2023]
Abstract
Spinal muscular atrophy with respiratory distress type 1 (SMARD1) is an infantile autosomal recessive disease caused by the loss of the ubiquitously expressed IGHMBP2 gene. SMARD1 causes degeneration of alpha-motor neurons, resulting in distal muscle weakness, diaphragm paralysis, and respiratory malfunction. We have reported that delivery of a low dose of AAV9-IGHMBP2 to the CNS results in a significant rescue of the SMARD1 mouse model (nmd). To examine how a delivery route can impact efficacy, a direct comparison of intravenous (IV) and intracerebroventricular (ICV) delivery of AAV9-IGHMBP2 was performed. Using a low-dose, both IV and ICV delivery routes led to a significant extension in survival and increased body weight. Conversely, only ICV-treated animals demonstrated improvements in the hindlimb muscle, neuromuscular junction, and motor function. The hindlimb phenotype of IV-treated mice resembled the untreated nmd mice. We investigated whether the increased survival of IV-treated nmd mice was the result of a positive impact on the cardiac function. Our results revealed that cardiac function and pathology were similarly improved in IV- and ICV-treated mice. We concluded that while IV delivery of a low dose does not improve the hindlimb phenotype and motor function, partial restoration of cardiac performance is sufficient to significantly extend survival.
Collapse
Affiliation(s)
- Monir Shababi
- Department of Veterinary Pathobiology, College of Veterinary Medicine, University of Missouri, Columbia, MO, USA.,Bond Life Sciences Center, University of Missouri, Columbia, MO, USA
| | - Eric Villalón
- Department of Veterinary Pathobiology, College of Veterinary Medicine, University of Missouri, Columbia, MO, USA.,Bond Life Sciences Center, University of Missouri, Columbia, MO, USA
| | - Kevin A Kaifer
- Department of Veterinary Pathobiology, College of Veterinary Medicine, University of Missouri, Columbia, MO, USA.,Bond Life Sciences Center, University of Missouri, Columbia, MO, USA
| | - Vince DeMarco
- Department of Medicine, Division of Endocrinology, Diabetes and Cardiovascular Center, University of Missouri, Columbia, MO, USA.,Department of Medical Pharmacology and Physiology, School of Medicine, University of Missouri, Columbia, MO, USA.,Research Service, Harry S. Truman Memorial Veterans Hospital, University of Missouri, Columbia, MO, USA
| | - Christian L Lorson
- Department of Veterinary Pathobiology, College of Veterinary Medicine, University of Missouri, Columbia, MO, USA.,Bond Life Sciences Center, University of Missouri, Columbia, MO, USA
| |
Collapse
|
31
|
Ikeda A, Yamashita S, Tsuyusaki Y, Tanaka M, Tanaka Y, Hashiguchi A, Takashima H, Goto T. Peripheral nerve pathology at fixed stage in spinal muscular atrophy with respiratory distress type 1. Brain Dev 2018; 40:155-158. [PMID: 28899595 DOI: 10.1016/j.braindev.2017.08.004] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/14/2017] [Revised: 08/16/2017] [Accepted: 08/23/2017] [Indexed: 10/18/2022]
Abstract
Spinal muscular atrophy with respiratory distress type 1 (SMARD1) is characterized by severe respiratory failure due to diaphragmatic paralysis and distal muscular weakness in early infancy. After an initial decline in respiratory state and motor function until 1-2years of age, residual capabilities reach a plateau. We report the peripheral neuropathological findings of a patient with SMARD1 at 1year and 1month of age, when his muscle strength and respiratory symptoms had deteriorated and then stabilized for several months. Peripheral nerve biopsy revealed severely progressed axonal degeneration. This finding suggests the rapid progression of peripheral axonal neuropathy in SMARD1 that leads to its characteristic clinical course of respiratory failure and paralysis in the early infantile period.
Collapse
Affiliation(s)
- Azusa Ikeda
- Department of Neurology, Kanagawa Children's Medical Center, Japan.
| | | | - Yu Tsuyusaki
- Department of Neurology, Kanagawa Children's Medical Center, Japan
| | - Mio Tanaka
- Department of Pathology, Kanagawa Children's Medical Center, Japan
| | - Yukichi Tanaka
- Department of Pathology, Kanagawa Children's Medical Center, Japan
| | - Akihiro Hashiguchi
- Department of Neurology and Geriatrics, Kagoshima University Graduate School of Medical and Dental Sciences, Japan
| | - Hiroshi Takashima
- Department of Neurology and Geriatrics, Kagoshima University Graduate School of Medical and Dental Sciences, Japan
| | - Tomohide Goto
- Department of Neurology, Kanagawa Children's Medical Center, Japan
| |
Collapse
|
32
|
Habibi Zoham M, Eghbalkhah A, Kamrani K, Khosroshahi N, Yousefimanesh H, Eskandarizadeh Z. Distal Spinal Muscular Atrophy: An Overlooked Etiology of Weaning Failure in Children with Respiratory Insufficiency. J Pediatr Intensive Care 2018; 7:159-162. [PMID: 31073488 DOI: 10.1055/s-0037-1617434] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2017] [Accepted: 12/01/2017] [Indexed: 10/18/2022] Open
Abstract
Spinal muscular atrophy with respiratory distress type 1 (SMARD1) is a rare autosomal recessive neuromuscular disorder that involves the anterior horn motor neurons. It is a disease with a poor prognosis presenting with progressive distal motor weakness and respiratory insufficiency from diaphragmatic paralysis followed by distal muscle weakness before 6 months of age. With the intent to spread the awareness of this rare and life-threatening disease, we report a 2.5-month-old female infant with a subsequent diagnosis of SMARD1, who was admitted in our pediatric intensive care unit with chief complaint of progressive respiratory distress and poor feeding.
Collapse
Affiliation(s)
- Mojdeh Habibi Zoham
- Department of Pediatric Intensive Care Unit, Bahrami Children's Hospital, Tehran University of Medical Sciences, Tehran, Islamic Republic of Iran
| | - Asgar Eghbalkhah
- Department of Pediatric Intensive Care Unit, Bahrami Children's Hospital, Tehran University of Medical Sciences, Tehran, Islamic Republic of Iran
| | - Kamyar Kamrani
- Department of Neonatal Intensive Care Unit, Bahrami Children's Hospital, Tehran University of Medical Sciences, Tehran, Islamic Republic of Iran
| | - Nahid Khosroshahi
- Department of Pediatric Neurology, Bahrami Children's Hospital, Tehran University of Medical Sciences, Tehran, Islamic Republic of Iran
| | - Hossein Yousefimanesh
- Department of Pediatric Intensive Care Unit, Bahrami Children's Hospital, Tehran University of Medical Sciences, Tehran, Islamic Republic of Iran
| | - Zahra Eskandarizadeh
- Department of Pediatric Intensive Care Unit, Bahrami Children's Hospital, Tehran University of Medical Sciences, Tehran, Islamic Republic of Iran
| |
Collapse
|
33
|
Yuan JH, Hashiguchi A, Yoshimura A, Yaguchi H, Tsuzaki K, Ikeda A, Wada-Isoe K, Ando M, Nakamura T, Higuchi Y, Hiramatsu Y, Okamoto Y, Takashima H. Clinical diversity caused by novel IGHMBP2 variants. J Hum Genet 2017; 62:599-604. [PMID: 28202949 DOI: 10.1038/jhg.2017.15] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2016] [Revised: 01/08/2017] [Accepted: 01/12/2017] [Indexed: 11/09/2022]
Abstract
Immunoglobulin helicase μ-binding protein 2 (IGHMBP2) gene is responsible for Charcot-Marie-Tooth disease (CMT) type 2S and spinal muscular atrophy with respiratory distress type 1 (SMARD1). From June 2014 to December 2015, we collected 408 cases, who referred to our genetic laboratory for genetic analysis, suspected with CMT disease or other inherited peripheral neuropathies (IPNs) on the basis of clinical manifestations and electrophysiological studies. Mutation screening was performed using Ion AmpliSeq Custom Panels, which comprise 72 disease-causing or candidate genes of IPNs. We identified novel homozygous or compound heterozygous variants of IGHMBP2 in four patients. Three patients presented with childhood-onset axonal predominant sensorimotor polyneuropathies, whereas the other case was diagnosed with SMARD1, manifesting as low birth weight, weak cry, reduced spontaneous movement and developed respiratory distress 4 months after birth. We present the original report of CMT type 2S in Japan, and illustrate that recessive IGHMBP2 variants account for ~1.6% of axonal CMT in our cohort.
Collapse
Affiliation(s)
- Jun-Hui Yuan
- Department of Neurology and Geriatrics, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima City, Japan
| | - Akihiro Hashiguchi
- Department of Neurology and Geriatrics, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima City, Japan
| | - Akiko Yoshimura
- Department of Neurology and Geriatrics, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima City, Japan
| | - Hiroshi Yaguchi
- Department of Neurology, The Jikei University Kashiwa Hospital, Chiba, Japan
| | - Koji Tsuzaki
- Department of Neurology, Kansai Electric Power Hospital, Osaka, Japan
| | - Azusa Ikeda
- Kanagawa Children's Medical Center, Yokohama, Japan
| | - Kenji Wada-Isoe
- Division of Neurology, Department of Brain and Neurosciences, Faculty of Medicine, Tottori University, Yonago, Japan
| | - Masahiro Ando
- Department of Neurology and Geriatrics, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima City, Japan
| | - Tomonori Nakamura
- Department of Neurology and Geriatrics, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima City, Japan
| | - Yujiro Higuchi
- Department of Neurology and Geriatrics, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima City, Japan
| | - Yu Hiramatsu
- Department of Neurology and Geriatrics, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima City, Japan
| | - Yuji Okamoto
- Department of Neurology and Geriatrics, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima City, Japan
| | - Hiroshi Takashima
- Department of Neurology and Geriatrics, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima City, Japan
| |
Collapse
|
34
|
Liu L, Li X, Hu Z, Mao X, Zi X, Xia K, Tang B, Zhang R. IGHMBP2 -related clinical and genetic features in a cohort of Chinese Charcot–Marie–Tooth disease type 2 patients. Neuromuscul Disord 2017; 27:193-199. [DOI: 10.1016/j.nmd.2016.11.008] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2016] [Accepted: 11/12/2016] [Indexed: 02/01/2023]
|
35
|
Biallelic Loss of Proprioception-Related PIEZO2 Causes Muscular Atrophy with Perinatal Respiratory Distress, Arthrogryposis, and Scoliosis. Am J Hum Genet 2016; 99:1206-1216. [PMID: 27843126 DOI: 10.1016/j.ajhg.2016.09.019] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2016] [Accepted: 09/26/2016] [Indexed: 11/23/2022] Open
Abstract
We report ten individuals of four independent consanguineous families from Turkey, India, Libya, and Pakistan with a variable clinical phenotype that comprises arthrogryposis, spontaneously resolving respiratory insufficiency at birth, muscular atrophy predominantly of the distal lower limbs, scoliosis, and mild distal sensory involvement. Using whole-exome sequencing, SNPchip-based linkage analysis, DNA microarray, and Sanger sequencing, we identified three independent homozygous frameshift mutations and a homozygous deletion of two exons in PIEZO2 that segregated in all affected individuals of the respective family. The mutations are localized in the N-terminal and central region of the gene, leading to nonsense-mediated transcript decay and consequently to lack of PIEZO2 protein. In contrast, heterozygous gain-of-function missense mutations, mainly localized at the C terminus, cause dominant distal arthrogryposis 3 (DA3), distal arthrogryposis 5 (DA5), or Marden-Walker syndrome (MWKS), which encompass contractures of hands and feet, scoliosis, ophthalmoplegia, and ptosis. PIEZO2 encodes a mechanosensitive ion channel that plays a major role in light-touch mechanosensation and has recently been identified as the principal mechanotransduction channel for proprioception. Mice ubiquitously depleted of PIEZO2 are postnatally lethal. However, individuals lacking PIEZO2 develop a not life-threatening, slowly progressive disorder, which is likely due to loss of PIEZO2 protein in afferent neurons leading to disturbed proprioception causing aberrant muscle development and function. Here we report a recessively inherited PIEZO2-related disease and demonstrate that depending on the type of mutation and the mode of inheritance, PIEZO2 causes clinically distinguishable phenotypes.
Collapse
|
36
|
Lingappa L, Shah N, Motepalli AS, Shaik F. Spinal muscular atrophy with respiratory distress syndrome (SMARD1): Case report and review of literature. Ann Indian Acad Neurol 2016; 19:395-8. [PMID: 27570397 PMCID: PMC4980968 DOI: 10.4103/0972-2327.168635] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Spinal muscular atrophy with respiratory distress syndrome (SMARD1) is a rare cause of early infantile respiratory failure and death. No cases have been currently described from India. Two low-birth-weight infants presented prior to 6 months of age with recurrent apnea and respiratory distress. Both required prolonged ventilation, and had distal arthrogryposis and diaphragmatic eventration. Nerve conduction study revealed motor sensory axonopathy. Genetic testing confirmed mutations in immunoglobulin mu binding protein (IGHMBP2). These two cases establish presence of SMARD1 in our population. Both infants died on discontinuation of ventilation. Antenatal diagnoses done in one pregnancy. Though rare, high index of suspicion is essential in view of poor outcome and aid antenatal counseling.
Collapse
Affiliation(s)
- Lokesh Lingappa
- Department of Pediatric Neurology, Rainbow Children's Hospital, Banjara Hills, Hyderabad, Telangana, India
| | - Nikit Shah
- Department of Pediatric Neurology, Rainbow Children's Hospital, Banjara Hills, Hyderabad, Telangana, India
| | - Ananth Sagar Motepalli
- Department of Pediatric Critical Care, Rainbow Children's Hospital, Banjara Hills, Hyderabad, Telangana, India
| | - Farhan Shaik
- Department of Pediatric Critical Care, Rainbow Children's Hospital, Banjara Hills, Hyderabad, Telangana, India
| |
Collapse
|
37
|
[Congenital neuromuscular diseases with neonatal respiratory failure excluding myotonic dystrophy type 1 and infantile spinal muscular atrophy. Diagnosis strategy according to a 19-child series]. Arch Pediatr 2016; 23:878-86. [PMID: 27375179 DOI: 10.1016/j.arcped.2016.05.019] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2013] [Revised: 01/22/2016] [Accepted: 05/08/2016] [Indexed: 11/20/2022]
Abstract
UNLABELLED Apart from spinal muscular atrophy (SMA) and myotonic dystrophy type 1 (DM1), congenital neuromuscular diseases with early neonatal symptoms mean diagnostic and prognostic challenges mainly when infants require ventilatory support. OBJECTIVES Consider a standardized strategy for infants suspected of congenital neuromuscular disease from analysis of the literature and retrospective experience with floppy and ventilatory support-dependent infants, after exclusion of well-known diseases (DM1, SMA). PATIENTS AND METHODS Floppy infants requiring ventilatory support in their 1st month of life, but showing no evidence of DM1, SMA, Prader-Willi syndrome, or encephalopathy. The retrospective multicenter study was based on the response of regional referent neuropediatricians in the Reference Centre for Neuromuscular Diseases of Greater Southwest France to an inquiry about prenatal and perinatal history, investigations, diagnosis, and outcome of the child and family. It was conducted between 2007 and 2012. RESULTS Among the 19 newborns studied, all had severe hypotonia. Prenatal and perinatal features were similar. Their outcome was generally severe: the median survival as measured by the Kaplan-Meier method was 6.9 months. Thirteen children died at a median age of 61 days; ten of them were treated with a palliative procedure. Five children had achieved respiratory independence but suffered from a small delay in motor development. Among the three children who continuously required ventilatory support, only one survived (follow-up period: 23 months); he was the only one undergoing tracheostomy in the cohort. Diagnostic processes were different, leading to pathological and genetic diagnosis for only six infants. There was only histological orientation for seven and no specific diagnostic orientation for the last six. These difficulties have led us to propose an exploration process based on the literature. CONCLUSION This study highlights difficulties in obtaining a diagnosis and a precise prognosis for floppy ventilated infants. An exploration-standardized process for infants suspected of congenital neuromuscular diseases was made in order to standardize procedures. It could be used as a tool for all professionals involved.
Collapse
|
38
|
Pedurupillay CRJ, Amundsen SS, Barøy T, Rasmussen M, Blomhoff A, Stadheim BF, Ørstavik K, Holmgren A, Iqbal T, Frengen E, Misceo D, Strømme P. Clinical and molecular characteristics in three families with biallelic mutations in IGHMBP2. Neuromuscul Disord 2016; 26:570-5. [PMID: 27450922 DOI: 10.1016/j.nmd.2016.06.457] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2015] [Revised: 06/09/2016] [Accepted: 06/20/2016] [Indexed: 11/28/2022]
Abstract
Biallelic mutations in IGHMBP2 cause spinal muscular atrophy with respiratory distress type 1 (SMARD1) or Charcot-Marie-Tooth type 2S (CMT2S). We report three families variably affected by IGHMBP2 mutations. Patient 1, an 8-year-old boy with two homozygous variants: c.2T>C and c.861C>G, was wheelchair bound due to sensorimotor axonal neuropathy and chronic respiratory failure. Patient 2 and his younger sister, Patient 3, had compound heterozygous variants: c.983_987delAAGAA and c.1478C>T. However, clinical phenotypes differed markedly as the elder with sensorimotor axonal neuropathy had still unaffected respiratory function at 4.5 years, whereas the younger presented as infantile spinal muscular atrophy and died from relentless respiratory failure at 11 months. Patient 4, a 6-year-old girl homozygous for IGHMBP2 c.449+1G>T documented to result in two aberrant transcripts, was wheelchair dependent due to axonal polyneuropathy. The clinical presentation in Patients 1 and 3 were consistent with SMARD1, whereas Patients 2 and 4 were in agreement with CMT2S.
Collapse
Affiliation(s)
- Christeen Ramane J Pedurupillay
- Department of Medical Genetics, Oslo University Hospital and University of Oslo, Oslo, Norway; Faculty of Medicine, University of Oslo, Oslo, Norway
| | - Silja S Amundsen
- Department of Medical Genetics, Oslo University Hospital and University of Oslo, Oslo, Norway
| | - Tuva Barøy
- Department of Medical Genetics, Oslo University Hospital and University of Oslo, Oslo, Norway; Faculty of Medicine, University of Oslo, Oslo, Norway
| | - Magnhild Rasmussen
- Women and Children's Division, Department of Clinical Neurosciences for Children, Oslo University Hospital, Oslo, Norway; Unit for Congenital and Hereditary Neuromuscular Disorders, Department of Neurology, Oslo University Hospital, Oslo, Norway
| | - Anne Blomhoff
- Department of Medical Genetics, Oslo University Hospital and University of Oslo, Oslo, Norway
| | - Barbro Fossøy Stadheim
- Department of Medical Genetics, Oslo University Hospital and University of Oslo, Oslo, Norway
| | | | - Asbjørn Holmgren
- Department of Medical Genetics, Oslo University Hospital and University of Oslo, Oslo, Norway
| | - Tahir Iqbal
- Molecular Biology laboratory, Department of Zoology, University of Gujrat, Gujrat, Pakistan
| | - Eirik Frengen
- Department of Medical Genetics, Oslo University Hospital and University of Oslo, Oslo, Norway; Faculty of Medicine, University of Oslo, Oslo, Norway
| | - Doriana Misceo
- Department of Medical Genetics, Oslo University Hospital and University of Oslo, Oslo, Norway; Faculty of Medicine, University of Oslo, Oslo, Norway
| | - Petter Strømme
- Faculty of Medicine, University of Oslo, Oslo, Norway; Women and Children's Division, Department of Clinical Neurosciences for Children, Oslo University Hospital, Oslo, Norway.
| |
Collapse
|
39
|
Rescue of a Mouse Model of Spinal Muscular Atrophy With Respiratory Distress Type 1 by AAV9-IGHMBP2 Is Dose Dependent. Mol Ther 2016; 24:855-66. [PMID: 26860981 DOI: 10.1038/mt.2016.33] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2015] [Accepted: 01/17/2016] [Indexed: 01/07/2023] Open
Abstract
Spinal muscular atrophy with respiratory distress type 1 (SMARD1) is an autosomal recessive disease occurring during childhood. The gene responsible for disease development is a ubiquitously expressed protein, IGHMBP2. Mutations in IGHMBP2 result in the loss of α-motor neurons leading to muscle atrophy in the distal limbs accompanied by respiratory complications. Although genetically and clinically distinct, proximal SMA is also caused by the loss of a ubiquitously expressed gene (SMN). Significant preclinical success has been achieved in proximal SMA using viral-based gene replacement strategies. We leveraged the technologies employed in SMA to demonstrate gene replacement efficacy in an SMARD1 animal model. Intracerebroventricular (ICV) injection of single-stranded AAV9 expressing the full-length cDNA of IGHMBP2 in a low dose led to a significant level of rescue in treated SMARD1 animals. Consistent with drastically increased survival, weight gain, and strength, the rescued animals demonstrated a significant improvement in muscle, NMJ, motor neurons, and axonal pathology. In addition, increased levels of IGHMBP2 in lumbar motor neurons verified the efficacy of the virus to transduce the target tissues. Our results indicate that AAV9-based gene replacement is a viable strategy for SMARD1, although dosing effects and potential negative impacts of high dose and ICV injection should be thoroughly investigated.
Collapse
|
40
|
Kleinkind mit sich früh entwickelnder Neuropathie, Klumpfüßen und im Verlauf zunehmender Schwäche der Atemmuskulatur. Monatsschr Kinderheilkd 2016. [DOI: 10.1007/s00112-015-0021-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
|
41
|
Spinal muscular atrophy with respiratory distress type 1 (SMARD1) Report of a Spanish case with extended clinicopathological follow-up. Clin Neuropathol 2015; 35:58-65. [PMID: 26709713 PMCID: PMC4806405 DOI: 10.5414/np300902] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/22/2016] [Indexed: 12/02/2022] Open
Abstract
Background: Spinal muscular atrophy with respiratory distress type 1 (SMARD1) is a clinically and genetically distinct and uncommon variant of SMA that results from irreversible degeneration of α-motor neurons in the anterior horns of the spinal cord and in ganglion cells on the spinal root ganglia. Aims: To describe the clinical, electrophysiological, neuropathological, and genetic findings, at different stages from birth to death, of a Spanish child diagnosed with SMARD1. Patient and methods: We report the case of a 3-month-old girl with severe respiratory insufficiency and, later, intense hypotonia. Paraclinical tests included biochemistry, chest X-ray, and electrophysiological studies, among others. Muscle and nerve biopsies were performed at 5 and 10 months and studied under light and electron microscopy. Post-mortem examination and genetic investigations were performed. Results: Pre- and post-mortem histopathological findings demonstrated the disease progression over time. Muscle biopsy at 5 months of age was normal, however a marked neurogenic atrophy was present in post-mortem samples. Peripheral motor and sensory nerves were severely involved likely due to a primary axonal disorder. Automatic sequencing of IGHMBP2 revealed a compound heterozygous mutation. Conclusions: The diagnosis of SMARD1 should be considered in children with early respiratory insufficiency or in cases of atypical SMA. Direct sequencing of the IGHMBP2 gene should be performed.
Collapse
|
42
|
Wagner JD, Huang L, Tetreault M, Majewski J, Boycott KM, Bulman DE, Dyment DA, McMillan HJ. Autosomal recessive axonal polyneuropathy in a sibling pair due to a novel homozygous mutation in IGHMBP2. Neuromuscul Disord 2015; 25:794-9. [PMID: 26298607 DOI: 10.1016/j.nmd.2015.07.017] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2015] [Revised: 06/05/2015] [Accepted: 07/29/2015] [Indexed: 11/30/2022]
Abstract
Charcot-Marie-Tooth disease is a group of genetically heterogeneous disorders characterized by a sensorimotor polyneuropathy with subsequent muscle atrophy, areflexia, and sensory loss. More than 60 genes have been linked to Charcot-Marie-Tooth phenotypes, including IGHMBP2. Until recently, mutations in IGHMBP2 were exclusively associated with spinal muscular atrophy with respiratory distress (SMARD1). We present a sibling pair with a novel homozygous truncating mutation in IGHMBP2. The patients presented with childhood-onset distal weakness, wasting in the upper and lower limbs, areflexia and decreased sensation, but no respiratory involvement. Exome sequencing was performed and a homozygous variant was identified (c.2601_2604del; p.Lys868Profs*109). Sanger sequencing confirmed the presence of this variant in a homozygous state in the two affected siblings, while both parents were heterozygous. Further analyses showed decreased mRNA and IGHMBP2 protein in a lymphoblast cell line derived from one of the siblings. We demonstrate the utility of next-generation sequencing in reaching a molecular diagnosis for a heterogeneous condition such as Charcot-Marie-Tooth. Taken together, our data and that from the literature suggest that the spectrum of clinical presentations associated with mutations in IGHMBP2 may be secondary, at least in part, to the amount of residual protein.
Collapse
Affiliation(s)
- Justin D Wagner
- Children's Hospital of Eastern Ontario Research Institute, University of Ottawa, Ottawa, ON, Canada
| | - Lijia Huang
- Children's Hospital of Eastern Ontario Research Institute, University of Ottawa, Ottawa, ON, Canada
| | - Martine Tetreault
- Department of Human Genetics, McGill University, Montréal, QC H3A 1B1, Canada
| | - Jacek Majewski
- Department of Human Genetics, McGill University, Montréal, QC H3A 1B1, Canada
| | - Kym M Boycott
- Children's Hospital of Eastern Ontario Research Institute, University of Ottawa, Ottawa, ON, Canada; Department of Genetics, Children's Hospital of Eastern Ontario, Ottawa, ON, Canada
| | - Dennis E Bulman
- Children's Hospital of Eastern Ontario Research Institute, University of Ottawa, Ottawa, ON, Canada
| | | | - David A Dyment
- Children's Hospital of Eastern Ontario Research Institute, University of Ottawa, Ottawa, ON, Canada; Department of Genetics, Children's Hospital of Eastern Ontario, Ottawa, ON, Canada
| | - Hugh J McMillan
- Children's Hospital of Eastern Ontario Research Institute, University of Ottawa, Ottawa, ON, Canada; Division of Neurology, Department of Pediatrics, Children's Hospital of Eastern Ontario, Ottawa, ON K1H 8L1, Canada.
| |
Collapse
|
43
|
Vanoli F, Rinchetti P, Porro F, Parente V, Corti S. Clinical and molecular features and therapeutic perspectives of spinal muscular atrophy with respiratory distress type 1. J Cell Mol Med 2015; 19:2058-66. [PMID: 26095024 PMCID: PMC4568910 DOI: 10.1111/jcmm.12606] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2014] [Accepted: 04/02/2015] [Indexed: 12/13/2022] Open
Abstract
Spinal muscular atrophy with respiratory distress (SMARD1) is an autosomal recessive neuromuscular disease caused by mutations in the IGHMBP2 gene, encoding the immunoglobulin μ-binding protein 2, leading to motor neuron degeneration. It is a rare and fatal disease with an early onset in infancy in the majority of the cases. The main clinical features are muscular atrophy and diaphragmatic palsy, which requires prompt and permanent supportive ventilation. The human disease is recapitulated in the neuromuscular degeneration (nmd) mouse. No effective treatment is available yet, but novel therapeutical approaches tested on the nmd mouse, such as the use of neurotrophic factors and stem cell therapy, have shown positive effects. Gene therapy demonstrated effectiveness in SMA, being now at the stage of clinical trial in patients and therefore representing a possible treatment for SMARD1 as well. The significant advancement in understanding of both SMARD1 clinical spectrum and molecular mechanisms makes ground for a rapid translation of pre-clinical therapeutic strategies in humans.
Collapse
Affiliation(s)
- Fiammetta Vanoli
- Dino Ferrari Centre, Neuroscience Section, Department of Pathophysiology and Transplantation (DEPT), University of Milan, Neurology Unit, IRCCS Foundation Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy
| | - Paola Rinchetti
- Dino Ferrari Centre, Neuroscience Section, Department of Pathophysiology and Transplantation (DEPT), University of Milan, Neurology Unit, IRCCS Foundation Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy
| | - Francesca Porro
- Dino Ferrari Centre, Neuroscience Section, Department of Pathophysiology and Transplantation (DEPT), University of Milan, Neurology Unit, IRCCS Foundation Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy
| | - Valeria Parente
- Dino Ferrari Centre, Neuroscience Section, Department of Pathophysiology and Transplantation (DEPT), University of Milan, Neurology Unit, IRCCS Foundation Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy
| | - Stefania Corti
- Dino Ferrari Centre, Neuroscience Section, Department of Pathophysiology and Transplantation (DEPT), University of Milan, Neurology Unit, IRCCS Foundation Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy
| |
Collapse
|
44
|
Han C, Mai J, Tian T, He Y, Liao J, Wen F, Yi X, Yang Y. Patient with spinal muscular atrophy with respiratory distress type 1 presenting initially with hypertonia. Brain Dev 2015; 37:542-5. [PMID: 25280635 DOI: 10.1016/j.braindev.2014.09.004] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/04/2014] [Revised: 08/20/2014] [Accepted: 09/09/2014] [Indexed: 02/05/2023]
Abstract
Spinal muscular atrophy with respiratory distress type 1 (SMARD1) is a rare autosomal recessive neuromuscular disorder caused by mutations in the IGHMBP2 gene and characterized by life-threatening respiratory distress due to irreversible diaphragmatic paralysis between 6weeks and 6months of age. In this study, we describe a two-month-old boy who presented with hypertonia at first and developed to hypotonia progressively, which was in contrast to the manifestations reported previously. Bone tissue compromise was also observed as one of the unique symptoms. Muscle biopsy indicated mild myogenic changes. He was misdiagnosed until genetic screening to be confirmed as SMARD1. SMARD1 is a clinical heterogeneous disease and this case broadens our perception of its phenotypes.
Collapse
Affiliation(s)
- Chunxi Han
- Department of Neurology, Shenzhen Children's Hospital, Shenzhen, Guangdong, China
| | - Jiahui Mai
- Department of Neurology, Shenzhen Children's Hospital, Shenzhen, Guangdong, China; Shantou University Medical College, Shantou, Guangdong, China
| | | | - Yanxia He
- Pediatric Intensive Care Unit, Shenzhen Children's Hospital, Shenzhen, Guangdong, China
| | - Jianxiang Liao
- Department of Neurology, Shenzhen Children's Hospital, Shenzhen, Guangdong, China
| | - Feiqiu Wen
- Department of Neurology, Shenzhen Children's Hospital, Shenzhen, Guangdong, China
| | | | | |
Collapse
|
45
|
Abstract
Spinal muscular atrophies (SMAs) are a group of inherited disorders characterized by motor neuron loss in the spinal cord and lower brainstem, muscle weakness, and atrophy. The clinical and genetic phenotypes incorporate a wide spectrum that is differentiated based on age of onset, pattern of muscle involvement, and inheritance pattern. Over the past several years, rapid advances in genetic technology have accelerated the identification of causative genes and provided important advances in understanding the molecular and biological basis of SMA and insights into the selective vulnerability of the motor neuron. Common pathophysiological themes include defects in RNA metabolism and splicing, axonal transport, and motor neuron development and connectivity. Together these have revealed potential novel treatment strategies, and extensive efforts are being undertaken towards expedited therapeutics. While a number of promising therapies for SMA are emerging, defining therapeutic windows and developing sensitive and relevant biomarkers are critical to facilitate potential success in clinical trials. This review incorporates an overview of the clinical manifestations and genetics of SMA, and describes recent advances in the understanding of mechanisms of disease pathogenesis and development of novel treatment strategies.
Collapse
Affiliation(s)
- Michelle A. Farrar
- />Discipline of Paediatrics, School of Women’s and Children’s Health, UNSW Medicine, The University of New South Wales, Sydney, Australia
- />Neurosciences Research Australia, Randwick, NSW Australia
- />Department of Neurology, Sydney Children’s Hospital, Randwick, NSW 2031 Australia
| | - Matthew C. Kiernan
- />Neurosciences Research Australia, Randwick, NSW Australia
- />Brain & Mind Research Institute, University of Sydney, Sydney, Australia
| |
Collapse
|
46
|
Madrid Rodríguez A, Martínez Martínez P, Ramos Fernández J, Urda Cardona A, Martínez Antón J. Atrofia muscular espinal: revisión de nuestra casuística en los últimos 25 años. An Pediatr (Barc) 2015; 82:159-65. [DOI: 10.1016/j.anpedi.2014.06.021] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2014] [Revised: 06/21/2014] [Accepted: 06/25/2014] [Indexed: 10/24/2022] Open
|
47
|
Madrid Rodríguez A, Martínez Martínez P, Ramos Fernández J, Urda Cardona A, Martínez Antón J. Infantile spinal atrophy: Our experience in the last 25 years. ANALES DE PEDIATRÍA (ENGLISH EDITION) 2015. [DOI: 10.1016/j.anpede.2014.06.005] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
|
48
|
Savaş T, Erol I, Özkale Y, Saygi S. Congenital segmental spinal muscular atrophy: a case report. J Child Neurol 2015; 30:509-12. [PMID: 25300987 DOI: 10.1177/0883073814550497] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/21/2014] [Accepted: 07/25/2014] [Indexed: 11/17/2022]
Abstract
Spinal muscular atrophies are genetic disorders in which anterior horn cells in the spinal cord and motor nuclei of the brainstem are progressively lost. We present a patient with arthrogryposis due to congenital spinal muscular atrophy predominantly affecting the upper limbs. Spinal muscular atrophies with onset at birth may be a cause of arthrogryposis. Localized forms of neurogenic arthrogryposis have been divided into cervical and caudal forms. Our case is similar to the cases described by Hageman et al (J Neurol Neurosurg Psychiatry 1993;56:365-368): severe symmetric lower motor neuron deficit in the upper extremities at the time of birth, no history of injury to the cervical spinal cord or the brachial plexus during delivery, and severe muscle wasting suggesting chronic denervation in utero. Because there was improvement of our patient's situation, her disease was also possibly nonprogressive and sporadic. To our knowledge, this is the first reported case of a Turkish patient with congenital cervical spinal muscular atrophy. Congenital cervical spinal muscular atrophy affecting predominantly the upper limbs is a relatively rare form of motor neuron disease and should be considered in the differential diagnosis of infants with congenital contractures and severe muscle weakness by wasting mainly confined to the upper limbs.
Collapse
Affiliation(s)
- Tülin Savaş
- Neurology Division, Department of Pediatrics, Baskent University Adana Teaching and Medical Research Center, Seyhan, Adana, Turkey
| | - Ilknur Erol
- Neurology Division, Department of Pediatrics, Baskent University Adana Teaching and Medical Research Center, Seyhan, Adana, Turkey
| | - Yasemin Özkale
- Department of Pediatrics, Baskent University Adana Teaching and Medical Research Center, Seyhan, Adana, Turkey
| | - Semra Saygi
- Neurology Division, Department of Pediatrics, Baskent University Adana Teaching and Medical Research Center, Seyhan, Adana, Turkey
| |
Collapse
|
49
|
Growing up with spinal muscular atrophy with respiratory distress (SMARD1). Neuromuscul Disord 2015; 25:169-71. [DOI: 10.1016/j.nmd.2014.10.005] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2014] [Revised: 09/30/2014] [Accepted: 10/16/2014] [Indexed: 11/17/2022]
|
50
|
Cottenie E, Kochanski A, Jordanova A, Bansagi B, Zimon M, Horga A, Jaunmuktane Z, Saveri P, Rasic VM, Baets J, Bartsakoulia M, Ploski R, Teterycz P, Nikolic M, Quinlivan R, Laura M, Sweeney MG, Taroni F, Lunn MP, Moroni I, Gonzalez M, Hanna MG, Bettencourt C, Chabrol E, Franke A, von Au K, Schilhabel M, Kabzińska D, Hausmanowa-Petrusewicz I, Brandner S, Lim SC, Song H, Choi BO, Horvath R, Chung KW, Zuchner S, Pareyson D, Harms M, Reilly MM, Houlden H. Truncating and missense mutations in IGHMBP2 cause Charcot-Marie Tooth disease type 2. Am J Hum Genet 2014; 95:590-601. [PMID: 25439726 DOI: 10.1016/j.ajhg.2014.10.002] [Citation(s) in RCA: 66] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2014] [Accepted: 10/01/2014] [Indexed: 11/18/2022] Open
Abstract
Using a combination of exome sequencing and linkage analysis, we investigated an English family with two affected siblings in their 40s with recessive Charcot-Marie Tooth disease type 2 (CMT2). Compound heterozygous mutations in the immunoglobulin-helicase-μ-binding protein 2 (IGHMBP2) gene were identified. Further sequencing revealed a total of 11 CMT2 families with recessively inherited IGHMBP2 gene mutations. IGHMBP2 mutations usually lead to spinal muscular atrophy with respiratory distress type 1 (SMARD1), where most infants die before 1 year of age. The individuals with CMT2 described here, have slowly progressive weakness, wasting and sensory loss, with an axonal neuropathy typical of CMT2, but no significant respiratory compromise. Segregating IGHMBP2 mutations in CMT2 were mainly loss-of-function nonsense in the 5' region of the gene in combination with a truncating frameshift, missense, or homozygous frameshift mutations in the last exon. Mutations in CMT2 were predicted to be less aggressive as compared to those in SMARD1, and fibroblast and lymphoblast studies indicate that the IGHMBP2 protein levels are significantly higher in CMT2 than SMARD1, but lower than controls, suggesting that the clinical phenotype differences are related to the IGHMBP2 protein levels.
Collapse
Affiliation(s)
- Ellen Cottenie
- MRC Centre for Neuromuscular Diseases, UCL Institute of Neurology, Queen Square, London WC1N 3BG, UK; Department of Molecular Neurosciences, UCL Institute of Neurology, Queen Square, London WC1N 3BG, UK
| | - Andrzej Kochanski
- Neuromuscular Unit, Mossakowski Medical Research Centre Polish Academy of Sciences, Centre of Biostructure, Medical University of Warsaw, Pawinskiego 5, 02-106 Warsaw, Poland
| | - Albena Jordanova
- VIB Department of Molecular Genetics, University of Antwerp, Antwerpen 2610, Belgium
| | - Boglarka Bansagi
- Institute of Genetic Medicine, MRC Centre for Neuromuscular Diseases, Newcastle University, Newcastle upon Tyne NE1 3BZ, UK
| | - Magdalena Zimon
- VIB Department of Molecular Genetics, University of Antwerp, Antwerpen 2610, Belgium
| | - Alejandro Horga
- MRC Centre for Neuromuscular Diseases, UCL Institute of Neurology, Queen Square, London WC1N 3BG, UK; Department of Molecular Neurosciences, UCL Institute of Neurology, Queen Square, London WC1N 3BG, UK
| | - Zane Jaunmuktane
- Division of Neuropathology and Department of Neurodegenerative Disease, UCL Institute of Neurology, Queen Square, London WC1N 3BG, UK
| | - Paola Saveri
- Clinic of Central and Peripheral Degenerative Neuropathies Unit, IRCCS Foundation, C. Besta Neurological Institute, Via Celoria 11, 20133 Milan, Italy
| | - Vedrana Milic Rasic
- Clinic for Neurology and Psychiatry for Children and Youth, Faculty of Medicine, University of Belgrade, 11000 Belgrade, Serbia
| | - Jonathan Baets
- VIB Department of Molecular Genetics, University of Antwerp, Antwerpen 2610, Belgium; Laboratory of Neurogenetics, University of Antwerp, Antwerpen 2610, Belgium; Department of Neurology, Antwerp University Hospital, Antwerpen, Belgium
| | - Marina Bartsakoulia
- Institute of Genetic Medicine, MRC Centre for Neuromuscular Diseases, Newcastle University, Newcastle upon Tyne NE1 3BZ, UK
| | - Rafal Ploski
- Department of Medical Genetics, Centre of Biostructure, Medical University of Warsaw, Pawinskiego 5, 02-106 Warsaw, Poland
| | - Pawel Teterycz
- Department of Medical Genetics, Centre of Biostructure, Medical University of Warsaw, Pawinskiego 5, 02-106 Warsaw, Poland
| | - Milos Nikolic
- University of Belgrade, Faculty of Medicine, 11000 Belgrade, Serbia
| | - Ros Quinlivan
- MRC Centre for Neuromuscular Diseases, UCL Institute of Neurology, Queen Square, London WC1N 3BG, UK
| | - Matilde Laura
- MRC Centre for Neuromuscular Diseases, UCL Institute of Neurology, Queen Square, London WC1N 3BG, UK; Department of Molecular Neurosciences, UCL Institute of Neurology, Queen Square, London WC1N 3BG, UK
| | - Mary G Sweeney
- Neurogenetics Laboratory, The National Hospital for Neurology and Neurosurgery and UCL Institute of Neurology, Queen Square, London WC1N 3BG, UK
| | - Franco Taroni
- Unit of Genetics of Neurodegenerative and Metabolic Disease IRCCS Foundation, C. Besta Neurological Institute, Via Celoria 11, 20133 Milan, Italy
| | - Michael P Lunn
- MRC Centre for Neuromuscular Diseases, UCL Institute of Neurology, Queen Square, London WC1N 3BG, UK
| | - Isabella Moroni
- Child Neurology Unit, IRCCS Foundation, C. Besta Neurological Institute, Via Celoria 11, 20133 Milan, Italy
| | - Michael Gonzalez
- John P. Hussman Institute for Human Genomics, University of Miami Miller School of Medicine, FL 33136, USA
| | - Michael G Hanna
- MRC Centre for Neuromuscular Diseases, UCL Institute of Neurology, Queen Square, London WC1N 3BG, UK; Department of Molecular Neurosciences, UCL Institute of Neurology, Queen Square, London WC1N 3BG, UK
| | - Conceicao Bettencourt
- Department of Molecular Neurosciences, UCL Institute of Neurology, Queen Square, London WC1N 3BG, UK
| | - Elodie Chabrol
- Department of Clinical and Experimental Epilepsy, UCL Institute of Neurology, Queen Square, London WC1N 3BG, UK
| | - Andre Franke
- Christian-Albrechts-University, 24118 Kiel, Germany
| | - Katja von Au
- SPZ Pediatric Neurology, Charité - Universitätsmedizin Berlin, 13353 Berlin, Germany
| | | | - Dagmara Kabzińska
- Neuromuscular Unit, Mossakowski Medical Research Centre Polish Academy of Sciences, Centre of Biostructure, Medical University of Warsaw, Pawinskiego 5, 02-106 Warsaw, Poland
| | - Irena Hausmanowa-Petrusewicz
- Neuromuscular Unit, Mossakowski Medical Research Centre Polish Academy of Sciences, Centre of Biostructure, Medical University of Warsaw, Pawinskiego 5, 02-106 Warsaw, Poland
| | - Sebastian Brandner
- Division of Neuropathology and Department of Neurodegenerative Disease, UCL Institute of Neurology, Queen Square, London WC1N 3BG, UK
| | - Siew Choo Lim
- Institute of Molecular and Cell Biology, 61 Biopolis Drive, Proteos, Singapore 138673
| | - Haiwei Song
- Institute of Molecular and Cell Biology, 61 Biopolis Drive, Proteos, Singapore 138673; Life Sciences Institute, Zhejiang University, Hangzhou 310058, People's Republic of China
| | - Byung-Ok Choi
- Department of Neurology, Sungkyunkwan University School of Medicine, Seoul 137-710, Korea
| | - Rita Horvath
- Institute of Genetic Medicine, MRC Centre for Neuromuscular Diseases, Newcastle University, Newcastle upon Tyne NE1 3BZ, UK
| | - Ki-Wha Chung
- Department of Biological Science, Kongju National University, Chungnam 134-701, Korea
| | - Stephan Zuchner
- John P. Hussman Institute for Human Genomics, University of Miami Miller School of Medicine, FL 33136, USA
| | - Davide Pareyson
- Clinic of Central and Peripheral Degenerative Neuropathies Unit, IRCCS Foundation, C. Besta Neurological Institute, Via Celoria 11, 20133 Milan, Italy
| | - Matthew Harms
- Department of Neurology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Mary M Reilly
- MRC Centre for Neuromuscular Diseases, UCL Institute of Neurology, Queen Square, London WC1N 3BG, UK; Department of Molecular Neurosciences, UCL Institute of Neurology, Queen Square, London WC1N 3BG, UK
| | - Henry Houlden
- MRC Centre for Neuromuscular Diseases, UCL Institute of Neurology, Queen Square, London WC1N 3BG, UK; Department of Molecular Neurosciences, UCL Institute of Neurology, Queen Square, London WC1N 3BG, UK; Neurogenetics Laboratory, The National Hospital for Neurology and Neurosurgery and UCL Institute of Neurology, Queen Square, London WC1N 3BG, UK.
| |
Collapse
|