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Riva N, Domi T, Pozzi L, Lunetta C, Schito P, Spinelli EG, Cabras S, Matteoni E, Consonni M, Bella ED, Agosta F, Filippi M, Calvo A, Quattrini A. Update on recent advances in amyotrophic lateral sclerosis. J Neurol 2024; 271:4693-4723. [PMID: 38802624 PMCID: PMC11233360 DOI: 10.1007/s00415-024-12435-9] [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: 04/09/2024] [Revised: 05/07/2024] [Accepted: 05/09/2024] [Indexed: 05/29/2024]
Abstract
In the last few years, our understanding of disease molecular mechanisms underpinning ALS has advanced greatly, allowing the first steps in translating into clinical practice novel research findings, including gene therapy approaches. Similarly, the recent advent of assistive technologies has greatly improved the possibility of a more personalized approach to supportive and symptomatic care, in the context of an increasingly complex multidisciplinary line of actions, which remains the cornerstone of ALS management. Against this rapidly growing background, here we provide an comprehensive update on the most recent studies that have contributed towards our understanding of ALS pathogenesis, the latest results from clinical trials as well as the future directions for improving the clinical management of ALS patients.
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Affiliation(s)
- Nilo Riva
- 3Rd Neurology Unit and Motor Neuron Disease Centre, Fondazione IRCCS "Carlo Besta" Neurological Insitute, Milan, Italy.
| | - Teuta Domi
- Experimental Neuropathology Unit, Division of Neuroscience, Institute of Experimental Neurology, IRCCS San Raffaele Scientific Institute, Milan, Italy
| | - Laura Pozzi
- Experimental Neuropathology Unit, Division of Neuroscience, Institute of Experimental Neurology, IRCCS San Raffaele Scientific Institute, Milan, Italy
| | - Christian Lunetta
- Istituti Clinici Scientifici Maugeri IRCCS, Neurorehabilitation Unit of Milan Institute, 20138, Milan, Italy
| | - Paride Schito
- Experimental Neuropathology Unit, Division of Neuroscience, Institute of Experimental Neurology, IRCCS San Raffaele Scientific Institute, Milan, Italy
- Department of Neurology, Division of Neuroscience, Institute of Experimental Neurology, IRCCS San Raffaele Scientific Institute, Milan, Italy
| | - Edoardo Gioele Spinelli
- Department of Neurology, Division of Neuroscience, Institute of Experimental Neurology, IRCCS San Raffaele Scientific Institute, Milan, Italy
- Neuroimaging Research Unit, Department of Neurology, Division of Neuroscience, Institute of Experimental Neurology, IRCCS San Raffaele Scientific Institute, Milan, Italy
| | - Sara Cabras
- ALS Centre, 'Rita Levi Montalcini' Department of Neuroscience, University of Turin; SC Neurologia 1U, AOU città della Salute e della Scienza di Torino, Turin, Italy
| | - Enrico Matteoni
- ALS Centre, 'Rita Levi Montalcini' Department of Neuroscience, University of Turin; SC Neurologia 1U, AOU città della Salute e della Scienza di Torino, Turin, Italy
| | - Monica Consonni
- 3Rd Neurology Unit and Motor Neuron Disease Centre, Fondazione IRCCS "Carlo Besta" Neurological Insitute, Milan, Italy
| | - Eleonora Dalla Bella
- 3Rd Neurology Unit and Motor Neuron Disease Centre, Fondazione IRCCS "Carlo Besta" Neurological Insitute, Milan, Italy
| | - Federica Agosta
- Department of Neurology, Division of Neuroscience, Institute of Experimental Neurology, IRCCS San Raffaele Scientific Institute, Milan, Italy
- Neuroimaging Research Unit, Department of Neurology, Division of Neuroscience, Institute of Experimental Neurology, IRCCS San Raffaele Scientific Institute, Milan, Italy
- Vita-Salute Huniversity, Milan, Italy
| | - Massimo Filippi
- Department of Neurology, Division of Neuroscience, Institute of Experimental Neurology, IRCCS San Raffaele Scientific Institute, Milan, Italy
- Neuroimaging Research Unit, Department of Neurology, Division of Neuroscience, Institute of Experimental Neurology, IRCCS San Raffaele Scientific Institute, Milan, Italy
- Vita-Salute Huniversity, Milan, Italy
| | - Andrea Calvo
- ALS Centre, 'Rita Levi Montalcini' Department of Neuroscience, University of Turin; SC Neurologia 1U, AOU città della Salute e della Scienza di Torino, Turin, Italy
| | - Angelo Quattrini
- Experimental Neuropathology Unit, Division of Neuroscience, Institute of Experimental Neurology, IRCCS San Raffaele Scientific Institute, Milan, Italy
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Tazir M, Nouioua S. Distal hereditary motor neuropathies. Rev Neurol (Paris) 2024:S0035-3787(23)01111-6. [PMID: 38702287 DOI: 10.1016/j.neurol.2023.09.005] [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: 08/02/2022] [Revised: 07/30/2023] [Accepted: 09/29/2023] [Indexed: 05/06/2024]
Abstract
Distal hereditary motor neuropathies (dHMN) are a group of heterogeneous hereditary disorders characterized by a slowly progressive distal pure motor neuropathy. Electrophysiology, with normal motor and sensory conduction velocities, can suggest the diagnosis of dHMN and guide the genetic study. More than thirty genes are currently associated with HMNs, but around 60 to 70% of cases of dHMN remain uncharacterized genetically. Recent cohort studies showed that HSPB1, GARS, BICB2 and DNAJB2 are among the most frequent dHMN genes and that the prevalence of the disease was calculated as 2.14 and 2.3 per 100,000. The determination of the different genes involved in dHMNs made it possible to observe a genotypic overlap with some other neurogenetic disorders and other hereditary neuropathies such as CMT2, mainly with the HSPB1, HSPB8, BICD2 and TRPV4 genes of AD-inherited transmission and recently observed with SORD gene of AR transmission which seems relatively frequent and potentially curable. Distal hereditary motor neuropathy that predominates in the upper limbs is linked mainly to three genes: GARS, BSCL2 and REEP1, whereas dHMN with vocal cord palsy is associated with SLC5A7, DCTN1 and TRPV4 genes. Among the rare AR forms of dHMN like IGHMBP2 and DNAJB2, the SIGMAR1 gene mutations as well as VRK1 variants are associated with a motor neuropathy phenotype often associated with upper motoneuron involvement. The differential diagnosis of these latter arises with juvenile forms of amyotrophic lateral sclerosis, that could be caused also by variations of these genes, as well as hereditary spastic paraplegia. A differential diagnosis of dHMN related to Brown Vialetto Van Laere syndrome due to riboflavin transporter deficiency is important to consider because of the therapeutic possibility.
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Affiliation(s)
- Meriem Tazir
- Department of Neurology, University Hospital Mustapha Bacha, Algiers, Algeria; Neurosciences Laboratory, University Benyoucef Benkhedda, Algiers, Algeria.
| | - Sonia Nouioua
- Neurosciences Laboratory, University Benyoucef Benkhedda, Algiers, Algeria; Department of Neurology, EHS El Maham, Cherchell,Tipaza, Algeria
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Tamanna N, Pi BK, Lee AJ, Kanwal S, Choi BO, Chung KW. Recessive GNE Mutations in Korean Nonaka Distal Myopathy Patients with or without Peripheral Neuropathy. Genes (Basel) 2024; 15:485. [PMID: 38674419 PMCID: PMC11050279 DOI: 10.3390/genes15040485] [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: 03/19/2024] [Revised: 04/05/2024] [Accepted: 04/07/2024] [Indexed: 04/28/2024] Open
Abstract
Autosomal recessive Nonaka distal myopathy is a rare autosomal recessive genetic disease characterized by progressive degeneration of the distal muscles, causing muscle weakness and decreased grip strength. It is primarily associated with mutations in the GNE gene, which encodes a key enzyme of sialic acid biosynthesis (UDP-N-acetylglucosamine 2-epimerase/N-acetylmannosamine kinase). This study was performed to find GNE mutations in six independent distal myopathy patients with or without peripheral neuropathy using whole-exome sequencing (WES). In silico pathogenic prediction and simulation of 3D structural changes were performed for the mutant GNE proteins. As a result, we identified five pathogenic or likely pathogenic missense variants: c.86T>C (p.Met29Thr), c.527A>T (p.Asp176Val), c.782T>C (p.Met261Thr), c.1714G>C (p.Val572Leu), and c.1771G>A (p.Ala591Thr). Five affected individuals showed compound heterozygous mutations, while only one patient revealed a homozygous mutation. Two patients revealed unreported combinations of combined heterozygous mutations. We observed some specific clinical features, such as complex phenotypes of distal myopathy with distal hereditary peripheral neuropathy, an earlier onset of weakness in legs than that of hands, and clinical heterogeneity between two patients with the same set of compound heterozygous mutations. Our findings on these genetic causes expand the clinical spectrum associated with the GNE mutations and can help prepare therapeutic strategies.
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Affiliation(s)
- Nasrin Tamanna
- Department of Biological Sciences, Kongju National University, Gongju 32588, Republic of Korea; (N.T.); (B.K.P.); (A.J.L.)
| | - Byung Kwon Pi
- Department of Biological Sciences, Kongju National University, Gongju 32588, Republic of Korea; (N.T.); (B.K.P.); (A.J.L.)
| | - Ah Jin Lee
- Department of Biological Sciences, Kongju National University, Gongju 32588, Republic of Korea; (N.T.); (B.K.P.); (A.J.L.)
| | - Sumaira Kanwal
- Department of Biosciences, COMSATS University Islamabad, Sahiwal 45550, Pakistan;
| | - Byung-Ok Choi
- Department of Neurology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul 06351, Republic of Korea
- Cell & Gene Therapy Institute, Samsung Medical Center, Seoul 06351, Republic of Korea
- Samsung Advanced Institute for Health Sciences & Technology, Seoul 06351, Republic of Korea
| | - Ki Wha Chung
- Department of Biological Sciences, Kongju National University, Gongju 32588, Republic of Korea; (N.T.); (B.K.P.); (A.J.L.)
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Pisciotta C, Pareyson D. Gene therapy and other novel treatment approaches for Charcot-Marie-Tooth disease. Neuromuscul Disord 2023; 33:627-635. [PMID: 37455204 DOI: 10.1016/j.nmd.2023.07.001] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2023] [Revised: 06/27/2023] [Accepted: 07/03/2023] [Indexed: 07/18/2023]
Abstract
There is still no effective drug treatment available for Charcot-Marie-Tooth disease (CMT). Current management relies on rehabilitation therapy, surgery for skeletal deformities, and symptomatic treatment. The challenge is to find disease-modifying therapies. Several approaches, including gene silencing (by means of ASO, siRNA, shRNA, miRNA, CRISPR-Cas9 editing), to counteract the PMP22 gene overexpression in the most frequent CMT1A type are under investigation. PXT3003 is the compound in the most advanced phase for CMT1A, as a second phase-III trial is ongoing. Gene therapy to substitute defective genes (particularly in recessive forms associated with loss-of-function mutations) or insert novel ones (e.g., NT3 gene) are being developed and tested in animal models and in still exceptional cases have reached the clinical trial phase in humans. Novel treatment approaches are also aimed at developing compounds acting on pathways important for different CMT types. Modulation of the neuregulin pathway determining myelin thickness is promising for both hypo-demyelinating and hypermyelinating neuropathies; intervention on Unfolded Protein Response seems effective for rescuing misfolded myelin proteins such as MPZ in CMT1B. HDAC6 inhibitors improved axonal transport and ameliorated phenotypes in different CMT models. Other potential therapeutic strategies include targeting macrophages, lipid metabolism, and Nav1.8 sodium channel in demyelinating CMT and the P2×7 receptor, which regulates calcium influx into Schwann cells, in CMT1A. Further approaches are aimed at correcting metabolic abnormalities, including the accumulation of sorbitol caused by biallelic mutations in the sorbitol dehydrogenase (SORD) gene and of neurotoxic glycosphingolipids in HSN1.
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Affiliation(s)
- Chiara Pisciotta
- Unit of Rare Neurological Diseases, Department of Clinical Neurosciences, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milan, Italy
| | - Davide Pareyson
- Unit of Rare Neurological Diseases, Department of Clinical Neurosciences, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milan, Italy.
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Lazo PA, Morejón-García P. VRK1 variants at the cross road of Cajal body neuropathogenic mechanisms in distal neuropathies and motor neuron diseases. Neurobiol Dis 2023; 183:106172. [PMID: 37257665 DOI: 10.1016/j.nbd.2023.106172] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2023] [Revised: 05/09/2023] [Accepted: 05/24/2023] [Indexed: 06/02/2023] Open
Abstract
Distal hereditary neuropathies and neuro motor diseases are complex neurological phenotypes associated with pathogenic variants in a large number of genes, but in some the origin is unknown. Recently, rare pathogenic variants of the human VRK1 gene have been associated with these neurological phenotypes. All VRK1 pathogenic variants are recessive, and their clinical presentation occurs in either homozygous or compound heterozygous patients. The pathogenic VRK1 gene pathogenic variants are located in three clusters within the protein sequence. The main, and initial, shared clinical phenotype among VRK1 pathogenic variants is a distal progressive loss of motor and/or sensory function, which includes diseases such as spinal muscular atrophy, Charcot-Marie-Tooth, amyotrophic lateral sclerosis and hereditary spastic paraplegia. In most cases, symptoms start early in infancy, or in utero, and are slowly progressive. Additional neurological symptoms vary among non-related patients, probably because of their different VRK1 variants and their genetic background. The underlying common pathogenic mechanism, by its functional impairment, is a likely consequence of the roles that the VRK1 protein plays in the regulation on the stability and assembly of Cajal bodies, which affect RNA maturation and processing, neuronal migration of RNPs along axons, and DNA-damage responses. Alterations of these processes are associated with several neuro sensory or motor syndromes. The clinical heterogeneity of the neurological phenotypes associated with VRK1 is a likely consequence of the protein complexes in which VRK1 is integrated, which include several proteins known to be associated with Cajal bodies and DNA damage responses. Several hereditary distal neurological diseases are a consequence of pathogenic variants in genes that alter these cellular functions. We conclude that VRK1-related distal hereditary neuropathies and motor neuron diseases represent a novel subgroup of Cajal body related neurological syndromes.
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Affiliation(s)
- Pedro A Lazo
- Molecular Mechanisms of Cancer Program, Instituto de Biología Molecular y Celular del Cáncer, Consejo Superior de Investigaciones Científicas (CSIC) - Universidad de Salamanca, Salamanca, Spain; Instituto de Investigación Biomédica de Salamanca (IBSAL), Hospital Universitario de Salamanca, Salamanca, Spain.
| | - Patricia Morejón-García
- Molecular Mechanisms of Cancer Program, Instituto de Biología Molecular y Celular del Cáncer, Consejo Superior de Investigaciones Científicas (CSIC) - Universidad de Salamanca, Salamanca, Spain; Instituto de Investigación Biomédica de Salamanca (IBSAL), Hospital Universitario de Salamanca, Salamanca, Spain.
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Islam A, Chakraborty A, Gambardella S, Campopiano R, Sarker AH, Boldogh I, Hazra T. Functional analysis of a conserved site mutation in the DNA end processing enzyme PNKP leading to ataxia with oculomotor apraxia type 4 in humans. J Biol Chem 2023; 299:104714. [PMID: 37061005 PMCID: PMC10197107 DOI: 10.1016/j.jbc.2023.104714] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2023] [Revised: 04/06/2023] [Accepted: 04/07/2023] [Indexed: 04/17/2023] Open
Abstract
Polynucleotide kinase 3'-phosphatase (PNKP), an essential DNA end-processing enzyme in mammals with 3'-phosphatase and 5'-kinase activities, plays a pivotal role in multiple DNA repair pathways. Its functional deficiency has been etiologically linked to various neurological disorders. Recent reports have shown that mutation at a conserved glutamine (Gln) in PNKP leads to late-onset ataxia with oculomotor apraxia type 4 (AOA4) in humans and embryonic lethality in pigs. However, the molecular mechanism underlying such phenotypes remains elusive. Here, we report that the enzymatic activities of the mutant versus WT PNKP are comparable; however, cells expressing mutant PNKP and peripheral blood mononuclear cells (PBMCs) of AOA4 patients showed a significant amount of DNA double-strand break accumulation and consequent activation of the DNA damage response. Further investigation revealed that the nuclear localization of mutant PNKP is severely abrogated, and the mutant proteins remain primarily in the cytoplasm. Western blot analysis of AOA4 patient-derived PBMCs also revealed the presence of mutated PNKP predominantly in the cytoplasm. To understand the molecular determinants, we identified that mutation at a conserved Gln residue impedes the interaction of PNKP with importin alpha but not with importin beta, two highly conserved proteins that mediate the import of proteins from the cytoplasm into the nucleus. Collectively, our data suggest that the absence of PNKP in the nucleus leads to constant activation of the DNA damage response due to persistent accumulation of double-strand breaks in the mutant cells, triggering death of vulnerable brain cells-a potential cause of neurodegeneration in AOA4 patients.
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Affiliation(s)
- Azharul Islam
- Department of Internal Medicine, University of Texas Medical Branch, Galveston, Texas, USA
| | - Anirban Chakraborty
- Department of Internal Medicine, University of Texas Medical Branch, Galveston, Texas, USA
| | - Stefano Gambardella
- IRCCS Neuromed & Department of Biomolecular Sciences, University of Urbino "Carlo Bo", Urbino, Italy
| | - Rosa Campopiano
- IRCCS Neuromed & Department of Biomolecular Sciences, University of Urbino "Carlo Bo", Urbino, Italy
| | - Altaf H Sarker
- Life Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California, USA
| | - Istvan Boldogh
- Department of Microbiology and Immunology, University of Texas Medical Branch, Galveston, Texas, USA
| | - Tapas Hazra
- Department of Internal Medicine, University of Texas Medical Branch, Galveston, Texas, USA.
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Ohno K, Ohkawara B, Shen XM, Selcen D, Engel AG. Clinical and Pathologic Features of Congenital Myasthenic Syndromes Caused by 35 Genes-A Comprehensive Review. Int J Mol Sci 2023; 24:ijms24043730. [PMID: 36835142 PMCID: PMC9961056 DOI: 10.3390/ijms24043730] [Citation(s) in RCA: 34] [Impact Index Per Article: 34.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2023] [Revised: 02/09/2023] [Accepted: 02/09/2023] [Indexed: 02/16/2023] Open
Abstract
Congenital myasthenic syndromes (CMS) are a heterogeneous group of disorders characterized by impaired neuromuscular signal transmission due to germline pathogenic variants in genes expressed at the neuromuscular junction (NMJ). A total of 35 genes have been reported in CMS (AGRN, ALG14, ALG2, CHAT, CHD8, CHRNA1, CHRNB1, CHRND, CHRNE, CHRNG, COL13A1, COLQ, DOK7, DPAGT1, GFPT1, GMPPB, LAMA5, LAMB2, LRP4, MUSK, MYO9A, PLEC, PREPL, PURA, RAPSN, RPH3A, SCN4A, SLC18A3, SLC25A1, SLC5A7, SNAP25, SYT2, TOR1AIP1, UNC13A, VAMP1). The 35 genes can be classified into 14 groups according to the pathomechanical, clinical, and therapeutic features of CMS patients. Measurement of compound muscle action potentials elicited by repetitive nerve stimulation is required to diagnose CMS. Clinical and electrophysiological features are not sufficient to identify a defective molecule, and genetic studies are always required for accurate diagnosis. From a pharmacological point of view, cholinesterase inhibitors are effective in most groups of CMS, but are contraindicated in some groups of CMS. Similarly, ephedrine, salbutamol (albuterol), amifampridine are effective in most but not all groups of CMS. This review extensively covers pathomechanical and clinical features of CMS by citing 442 relevant articles.
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Affiliation(s)
- Kinji Ohno
- Division of Neurogenetics, Center for Neurological Diseases and Cancer, Nagoya University Graduate School of Medicine, Nagoya 466-8550, Japan
- Correspondence: (K.O.); (A.G.E.)
| | - Bisei Ohkawara
- Division of Neurogenetics, Center for Neurological Diseases and Cancer, Nagoya University Graduate School of Medicine, Nagoya 466-8550, Japan
| | - Xin-Ming Shen
- Department of Neurology and Neuromuscular Research Laboratory, Mayo Clinic, Rochester, MN 55905, USA
| | - Duygu Selcen
- Department of Neurology and Neuromuscular Research Laboratory, Mayo Clinic, Rochester, MN 55905, USA
| | - Andrew G. Engel
- Department of Neurology and Neuromuscular Research Laboratory, Mayo Clinic, Rochester, MN 55905, USA
- Correspondence: (K.O.); (A.G.E.)
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Cipriani S, Guerrero-Valero M, Tozza S, Zhao E, Vollmer V, Beijer D, Danzi M, Rivellini C, Lazarevic D, Pipitone GB, Grosz BR, Lamperti C, Marzoli SB, Carrera P, Devoto M, Pisciotta C, Pareyson D, Kennerson M, Previtali SC, Zuchner S, Scherer SS, Manganelli F, Bähler M, Bolino A. Mutations in MYO9B are associated with Charcot-Marie-Tooth disease type 2 neuropathies and isolated optic atrophy. Eur J Neurol 2023; 30:511-526. [PMID: 36260368 PMCID: PMC10099703 DOI: 10.1111/ene.15601] [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: 10/04/2022] [Accepted: 10/11/2022] [Indexed: 01/20/2023]
Abstract
BACKGROUND AND PURPOSE Charcot-Marie-Tooth disease (CMT) is a heterogeneous group of disorders caused by mutations in at least 100 genes. However, approximately 60% of cases with axonal neuropathies (CMT2) still remain without a genetic diagnosis. We aimed at identifying novel disease genes responsible for CMT2. METHODS We performed whole exome sequencing and targeted next generation sequencing panel analyses on a cohort of CMT2 families with evidence for autosomal recessive inheritance. We also performed functional studies to explore the pathogenetic role of selected variants. RESULTS We identified rare, recessive variants in the MYO9B (myosin IX) gene in two families with CMT2. MYO9B has not yet been associated with a human disease. MYO9B is an unconventional single-headed processive myosin motor protein with signaling properties, and, consistent with this, our results indicate that a variant occurring in the MYO9B motor domain impairs protein expression level and motor activity. Interestingly, a Myo9b-null mouse has degenerating axons in sciatic nerves and optic nerves, indicating that MYO9B plays an essential role in both peripheral nervous system and central nervous system axons, respectively. The degeneration observed in the optic nerve prompted us to screen for MYO9B mutations in a cohort of patients with optic atrophy (OA). Consistent with this, we found compound heterozygous variants in one case with isolated OA. CONCLUSIONS Novel or very rare variants in MYO9B are associated with CMT2 and isolated OA.
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Affiliation(s)
- Silvia Cipriani
- Division of Neuroscience, Institute of Experimental Neurology, IRCCS Ospedale San Raffaele, Milan, Italy
| | - Marta Guerrero-Valero
- Division of Neuroscience, Institute of Experimental Neurology, IRCCS Ospedale San Raffaele, Milan, Italy
| | - Stefano Tozza
- Department of Neurosciences, Reproductive Sciences and Odontostomatology, University of Naples Federico II, Naples, Italy
| | - Edward Zhao
- Vaccine and Infectious Disease Division, Fred Hutchinson Cancer Research Center, Seattle, Washington, USA
- Department of Biostatistics, University of Washington, Seattle, Washington, USA
| | - Veith Vollmer
- Institute of Integrative Cell Biology and Physiology, Westfalian Wilhelms University Münster, Münster, Germany
| | - Danique Beijer
- Department of Human Genetics and Hussman Institute for Human Genomics, University of Miami, Miami, Florida, USA
| | - Matt Danzi
- Department of Human Genetics and Hussman Institute for Human Genomics, University of Miami, Miami, Florida, USA
| | - Cristina Rivellini
- Division of Neuroscience, Institute of Experimental Neurology, IRCCS Ospedale San Raffaele, Milan, Italy
| | - Dejan Lazarevic
- Center for Omics Sciences, IRCCS Ospedale San Raffaele, Milan, Italy
| | - Giovanni Battista Pipitone
- Unit of Genomics for the Diagnosis of Human Pathologies and Laboratory of Clinical and Molecular Biology, IRCCS Ospedale San Raffaele, Milan, Italy
| | - Bianca Rose Grosz
- Northcott Neuroscience Laboratory, ANZAC Research Institute Sydney Local Health District and Faculty of Health and Medicine, University of Sydney, Sydney, Australia
| | - Costanza Lamperti
- Genetics and Neurogenetics Unit, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milan, Italy
| | - Stefania Bianchi Marzoli
- Neuroophthalmology Service and Ocular Electrophysiology laboratory, Department of Ophthalmology, Scientific Institute, Auxologico Capitanio Hospital, Milan, Italy
| | - Paola Carrera
- Unit of Genomics for the Diagnosis of Human Pathologies and Laboratory of Clinical and Molecular Biology, IRCCS Ospedale San Raffaele, Milan, Italy
| | - Marcella Devoto
- Division of Genetics, Children's Hospital of Philadelphia, Department of Pediatrics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
- CNR-IRGB, Cagliari, Italy
| | - Chiara Pisciotta
- Unit of Rare Neurodegenerative and Neurometabolic Diseases, Department of Clinical Neurosciences, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milan, Italy
| | - Davide Pareyson
- Unit of Rare Neurodegenerative and Neurometabolic Diseases, Department of Clinical Neurosciences, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milan, Italy
| | - Marina Kennerson
- Northcott Neuroscience Laboratory, ANZAC Research Institute Sydney Local Health District and Faculty of Health and Medicine, University of Sydney, Sydney, Australia
| | - Stefano C Previtali
- Division of Neuroscience, Institute of Experimental Neurology, IRCCS Ospedale San Raffaele, Milan, Italy
- Department of Neurology, IRCCS Ospedale San Raffaele, Milan, Italy
| | - Stephan Zuchner
- Department of Human Genetics and Hussman Institute for Human Genomics, University of Miami, Miami, Florida, USA
| | - Steven S Scherer
- Department of Neurology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Fiore Manganelli
- Department of Neurosciences, Reproductive Sciences and Odontostomatology, University of Naples Federico II, Naples, Italy
| | - Martin Bähler
- Institute of Integrative Cell Biology and Physiology, Westfalian Wilhelms University Münster, Münster, Germany
| | - Alessandra Bolino
- Division of Neuroscience, Institute of Experimental Neurology, IRCCS Ospedale San Raffaele, Milan, Italy
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刘 小, 段 晓, 张 朔, 孙 阿, 张 英, 樊 东. [Genetic distribution in Chinese patients with hereditary peripheral neuropathy]. BEIJING DA XUE XUE BAO. YI XUE BAN = JOURNAL OF PEKING UNIVERSITY. HEALTH SCIENCES 2022; 54:874-883. [PMID: 36241230 PMCID: PMC9568373 DOI: 10.19723/j.issn.1671-167x.2022.05.015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Received: 07/02/2022] [Indexed: 06/16/2023]
Abstract
OBJECTIVE To analyze the distribution characteristics of hereditary peripheral neuropathy (HPN) pathogenic genes in Chinese Han population, and to explore the potential pathogenesis and treatment prospects of HPN and related diseases. METHODS Six hundred and fifty-six index patients with HPN were enrolled in Peking University Third Hospital and China-Japan Friendship Hospital from January 2007 to May 2022. The PMP22 duplication and deletion mutations were screened and validated by multiplex ligation probe amplification technique. The next-generation sequencing gene panel or whole exome sequencing was used, and the suspected genes were validated by Sanger sequencing. RESULTS Charcot-Marie-Tooth (CMT) accounted for 74.3% (495/666) of the patients with HPN, of whom 69.1% (342/495) were genetically confirmed. The most common genes of CMT were PMP22 duplication, MFN2 and GJB1 mutations, which accounted for 71.3% (244/342) of the patients with genetically confirmed CMT. Hereditary motor neuropathy (HMN) accounted for 16.1% (107/666) of HPN, and 43% (46/107) of HPN was genetically confirmed. The most common genes of HMN were HSPB1, aminoacyl tRNA synthetases and SORD mutations, which accounted for 56.5% (26/46) of the patients with genetically confirmed HMN. Most genes associated with HMN could cause different phenotypes. HMN and CMT shared many genes (e.g. HSPB1, GARS, IGHMBP2). Some genes associated with dHMN-plus shared genes associated with amyotrophic lateral sclerosis (KIF5A, FIG4, DCTN1, SETX, VRK1), hereditary spastic paraplegia (KIF5A, ZFYVE26, BSCL2) and spinal muscular atrophy (MORC2, IGHMBP, DNAJB2), suggesting that HMN was a continuum rather than a distinct entity. Hereditary sensor and autosomal neuropathy (HSAN) accounted for a small proportion of 2.6% (17/666) in HPN. The most common pathogenic gene was SPTLC1 mutation. TTR was the main gene causing hereditary amyloid peripheral neuropathy. The most common types of gene mutations were p.A117S and p.V50M. The symptoms were characterized by late-onset and prominent autonomic nerve involvement. CONCLUSION CMT and HMN are the most common diseases of HPN. There is a large overlap between HMN and motor-CMT2 pathogenic genes, and some HMN pathogenic genes overlap with amyotrophic lateral sclerosis, hereditary spastic hemiplegia and spinal muscular atrophy, suggesting that there may be a potential common pathogenic pathway between different diseases.
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Affiliation(s)
- 小璇 刘
- 北京大学第三医院神经内科,北京 100191Department of Neurology, Peking University Third Hospital, Beijing 100191, China
| | - 晓慧 段
- 中日友好医院神经内科,北京 100029Department of Neurology, China-Japan Friendship Hospital, Beijing 100029, China
| | - 朔 张
- 北京大学第三医院神经内科,北京 100191Department of Neurology, Peking University Third Hospital, Beijing 100191, China
| | - 阿萍 孙
- 北京大学第三医院神经内科,北京 100191Department of Neurology, Peking University Third Hospital, Beijing 100191, China
| | - 英爽 张
- 北京大学第三医院神经内科,北京 100191Department of Neurology, Peking University Third Hospital, Beijing 100191, China
| | - 东升 樊
- 北京大学第三医院神经内科,北京 100191Department of Neurology, Peking University Third Hospital, Beijing 100191, China
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10
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Frasquet M, Sevilla T. Hereditary motor neuropathies. Curr Opin Neurol 2022; 35:562-570. [PMID: 35942667 DOI: 10.1097/wco.0000000000001087] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
PURPOSE OF REVIEW Distal hereditary motor neuropathies (dHMN) are a clinically and genetically diverse group of disorders that are characterized by length-dependent axonal degeneration of lower motor neurons. In this review, we will provide an overview of dHMN, and we will correlate the distinct clinical subtypes with their causative genes, focusing on the most recent advances in the field. RECENT FINDINGS Despite the massive use of new-generation sequencing (NGS) and the discovery of new genes, only a third of dHMN patients receive a molecular diagnosis. Thanks to international cooperation between researchers, new genes have been implicated in dHMN, such as SORD and VWA1 . Mutations in SORD are the most frequent cause of autosomal recessive forms of dHMN. As a result of these findings, the potential benefits of some pharmacological compounds are being studied in cell and animal models, mainly targeting axonal transport and metabolic pathways. SUMMARY Despite the wide use of NGS, the diagnosis of dHMN remains a challenge. The low prevalence of dHMN makes international cooperation necessary in order to discover new genes and causal mechanisms. Genetic diagnosis of patients and identification of new pathomechanism are essential for the development of therapeutical clinical trials.
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Affiliation(s)
- Marina Frasquet
- Department of Neurology, Hospital Universitari Doctor Peset
- Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER) Spain
| | - Teresa Sevilla
- Neuromuscular Diseases Unit, Department of Neurology, Hospital Universitari i Politècnic La Fe
- Neuromuscular and Ataxias Research Group, Instituto de Investigación Sanitaria La Fe
- Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER) Spain
- Universitat de València, Valencia, Spain
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11
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The role of amyloid β in the pathological mechanism of GNE myopathy. Neurol Sci 2022; 43:6309-6321. [PMID: 35904705 PMCID: PMC9616754 DOI: 10.1007/s10072-022-06301-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2022] [Accepted: 07/21/2022] [Indexed: 11/18/2022]
Abstract
GNE myopathy is a hereditary muscle disorder characterized by muscle atrophy and weakness initially involving the lower distal extremities. The treatment of GNE myopathy mainly focuses on a sialic acid deficiency caused by a mutation in the GNE gene, but it has not achieved the expected effect. The main pathological features of GNE myopathy are myofiber atrophy and rimmed vacuoles, including accumulation of amyloid β, which is mainly found in atrophic muscle fibers. Although the role of amyloid β and other misfolded proteins on the nervous system has been widely recognized, the cause and process of the formation of amyloid β in the pathological process of GNE myopathy are unclear. In addition, amyloid β has been reported to be linked to quality control mechanisms of proteins, such as molecular chaperones, the ubiquitin–proteasome system, and the autophagy-lysosome system. Herein, we summarize the possible reasons for amyloid β deposition and illustrate amyloid β-mediated events in the cells and their role in muscle atrophy in GNE myopathy. This review represents an overview of amyloid β and GNE myopathy that could help identify a potential mechanism and thereby a plausible therapeutic for the disease.
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12
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Liu X, Zhang Y, Zhang S, Sun A, Zheng D, Fan D, Liu X. Different electrophysiology patterns in GNE myopathy. Orphanet J Rare Dis 2022; 17:206. [PMID: 35590323 PMCID: PMC9118620 DOI: 10.1186/s13023-022-02355-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2021] [Accepted: 05/08/2022] [Indexed: 12/24/2022] Open
Abstract
Background GNE myopathy is a rare distal myopathy caused by mutations of the GNE gene. A few cases of GNE myopathy accompanied by neurogenic features of electrophysiology mimicking hereditary motor neuropathy were reported recently. We confirmed this feature and described the clinical phenotype and mutations of GNE myopathy in these rare cases. Results The absence of lower limb tendon reflexes, decreased compound muscle action potentials in lower leg motor nerves, and neurogenic pattern of electromyography suggested neuropathy in four patients. However, muscle pathology revealed a predominantly myogenic pattern. The follow-up electroneurography results implied that the compound motor action potential amplitudes deteriorated over time. Next-generation sequencing identified three novel variants of the GNE gene, c.2054T > C (p.Val685Ala), c.424G > A (p.Gly142Arg) and c.944T > C (p.Phe315Ser), as well as two hotspot mutations, c.115C > T(p.Arg39*) and c.620A > T(p.Asp207Val), in these patients. These novel mutations cosegregated with disease in the family. Conclusions These rare cases supported the existence of neurogenic features of electrophysiology different from the typical myopathic pattern of GNE myopathy. Supplementary Information The online version contains supplementary material available at 10.1186/s13023-022-02355-0.
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Affiliation(s)
- Xiangyi Liu
- Department of Neurology, Peking University Third Hospital, No. 49, North Garden Road, Haidian District, Beijing, 100191, China
| | - Yingshuang Zhang
- Department of Neurology, Peking University Third Hospital, No. 49, North Garden Road, Haidian District, Beijing, 100191, China
| | - Shuo Zhang
- Department of Neurology, Peking University Third Hospital, No. 49, North Garden Road, Haidian District, Beijing, 100191, China
| | - Aping Sun
- Department of Neurology, Peking University Third Hospital, No. 49, North Garden Road, Haidian District, Beijing, 100191, China
| | - Danfeng Zheng
- Department of Neurology, Peking University Third Hospital, No. 49, North Garden Road, Haidian District, Beijing, 100191, China
| | - Dongsheng Fan
- Department of Neurology, Peking University Third Hospital, No. 49, North Garden Road, Haidian District, Beijing, 100191, China
| | - Xiaoxuan Liu
- Department of Neurology, Peking University Third Hospital, No. 49, North Garden Road, Haidian District, Beijing, 100191, China.
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13
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Mahungu AC, Monnakgotla N, Nel M, Heckmann JM. A review of the genetic spectrum of hereditary spastic paraplegias, inherited neuropathies and spinal muscular atrophies in Africans. Orphanet J Rare Dis 2022; 17:133. [PMID: 35331287 PMCID: PMC8944057 DOI: 10.1186/s13023-022-02280-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2021] [Accepted: 03/07/2022] [Indexed: 11/10/2022] Open
Abstract
Background Genetic investigations of inherited neuromuscular disorders in Africans, have been neglected. We aimed to summarise the published data and comment on the genetic evidence related to inherited neuropathies (Charcot-Marie-Tooth disease (CMT)), hereditary spastic paraplegias (HSP) and spinal muscular atrophy (SMA) in Africans. Methods PubMed was searched for relevant articles and manual checking of references and review publications were performed for African-ancestry participants with relevant phenotypes and identified genetic variants. For each case report we extracted phenotype information, inheritance pattern, variant segregation and variant frequency in population controls (including up to date frequencies from the gnomAD database). Results For HSP, 23 reports were found spanning the years 2000–2019 of which 19 related to North Africans, with high consanguinity, and six included sub-Saharan Africans. For CMT, 19 reports spanning years 2002–2021, of which 16 related to North Africans and 3 to sub-Saharan Africans. Most genetic variants had not been previously reported. There were 12 reports spanning years 1999–2020 related to SMN1-SMA caused by homozygous exon 7 ± 8 deletion. Interestingly, the population frequency of heterozygous SMN1-exon 7 deletion mutations appeared 2 × lower in Africans compared to Europeans, in addition to differences in the architecture of the SMN2 locus which may impact SMN1-SMA prognosis. Conclusions Overall, genetic data on inherited neuromuscular diseases in sub-Saharan Africa, are sparse. If African patients with rare neuromuscular diseases are to benefit from the expansion in genomics capabilities and therapeutic advancements, then it is critical to document the mutational spectrum of inherited neuromuscular disease in Africa. Highlights Review of genetic variants reported in hereditary spastic paraplegia in Africans Review of genetic variants reported in genetic neuropathies in Africans Review of genetic underpinnings of spinal muscular atrophies in Africans Assessment of pathogenic evidence for candidate variants
Supplementary Information The online version contains supplementary material available at 10.1186/s13023-022-02280-2.
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Affiliation(s)
- Amokelani C Mahungu
- Neurology Research Group, University of Cape Town Neuroscience Institute, Cape Town, South Africa
| | | | - Melissa Nel
- Neurology Research Group, University of Cape Town Neuroscience Institute, Cape Town, South Africa
| | - Jeannine M Heckmann
- E8-74 Neurology, Department of Medicine, Groote Schuur Hospital and the University of Cape Town Neuroscience Institute, University of Cape Town, Cape Town, South Africa.
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14
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Saveri P, Magri S, Maderna E, Balistreri F, Lombardi R, Ciano C, Moda F, Garavaglia B, Reale C, Lauria Pinter G, Taroni F, Pareyson D, Pisciotta C. DNAJB2-related CMT2: Pathomechanism insights and phenotypic spectrum widening. Eur J Neurol 2022; 29:2056-2065. [PMID: 35286755 PMCID: PMC9314055 DOI: 10.1111/ene.15326] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2021] [Revised: 02/14/2022] [Accepted: 03/09/2022] [Indexed: 11/29/2022]
Abstract
Background and purpose Mutations in DNAJB2 are associated with autosomal recessive hereditary motor neuropathies/ Charcot‐Marie‐Tooth disease type 2 (CMT2). We describe an Italian family with CMT2 due to a homozygous DNAJB2 mutation and provide insight into the pathomechanisms. Methods Patients with DNAJB2 mutations were characterized clinically, electrophysiologically and by means of skin biopsy. mRNA and protein levels were studied in lymphoblastoid cells (LCLs) from patients and controls. Results Three affected siblings were found to carry a homozygous DNAJB2 null mutation segregating with the disease. The disease manifested in the second to third decade of life. Clinical examination showed severe weakness of the thigh muscles and complete loss of movement in the foot and leg muscles. Sensation was reduced in the lower limbs. All patients had severe hearing loss and the proband also had Parkinson’s disease (PD). Nerve conduction studies showed an axonal motor and sensory length‐dependent polyneuropathy. DNAJB2 expression studies revealed reduced mRNA levels and the absence of the protein in the homozygous subject in both LCLs and skin biopsy. Interestingly, we detected phospho‐alpha‐synuclein deposits in the proband, as already seen in PD patients, and demonstrated TDP‐43 accumulation in patients’ skin. Conclusions Our results broaden the clinical spectrum of DNAJB2‐related neuropathies and provide evidence that DNAJB2 mutations should be taken into account as another causative gene of CMT2 with hearing loss and parkinsonism. The mutation likely acts through a loss‐of‐function mechanism, leading to toxic protein aggregation such as TDP‐43. The associated parkinsonism resembles the classic PD form with the addition of abnormal accumulation of phospho‐alpha‐synuclein.
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Affiliation(s)
- Paola Saveri
- Department of Clinical Neurosciences, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milan, Italy
| | - Stefania Magri
- Department of Diagnostics and Applied Technology, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milan, Italy
| | - Emanuela Maderna
- Department of Diagnostics and Applied Technology, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milan, Italy
| | - Francesca Balistreri
- Department of Diagnostics and Applied Technology, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milan, Italy
| | - Raffaella Lombardi
- Department of Clinical Neurosciences, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milan, Italy
| | - Claudia Ciano
- Department of Diagnostics and Applied Technology, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milan, Italy
| | - Fabio Moda
- Department of Diagnostics and Applied Technology, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milan, Italy
| | - Barbara Garavaglia
- Department of Diagnostics and Applied Technology, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milan, Italy
| | - Chiara Reale
- Department of Diagnostics and Applied Technology, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milan, Italy
| | - Giuseppe Lauria Pinter
- Department of Clinical Neurosciences, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milan, Italy.,Department of Medical Biotechnology and Translational Medicine, University of Milan, Milan, Italy
| | - Franco Taroni
- Department of Diagnostics and Applied Technology, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milan, Italy
| | - Davide Pareyson
- Department of Clinical Neurosciences, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milan, Italy
| | - Chiara Pisciotta
- Department of Clinical Neurosciences, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milan, Italy
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15
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Jiang X, Shen X, Talap J, Yang D, Zeng S, Liu H, Cai S. Phosphorothioated and phosphate-terminal dumbbell (PP-TD) probe-based rapid detection of polynucleotide kinase activity. Analyst 2022; 147:4986-4990. [DOI: 10.1039/d2an01431a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
A primer-free, sensitive assay has been developed to detect polynucleotide kinase (PNK) activity. This proposed method provides a promising platform for PNK activity monitoring and inhibition screening for drug discovery and clinical treatment.
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Affiliation(s)
- Xianfeng Jiang
- Sir Run Run Shaw Hospital, School of Medicine, Zhejiang University, Hangzhou, Zhejiang 310020, China
| | - Xudan Shen
- Institute of Drug Metabolism and Pharmaceutical Analysis, College of Pharmaceutical Science, Zhejiang University, Hangzhou, Zhejiang 310058, China
| | - Jadera Talap
- Institute of Drug Metabolism and Pharmaceutical Analysis, College of Pharmaceutical Science, Zhejiang University, Hangzhou, Zhejiang 310058, China
| | - Dan Yang
- Institute of Drug Metabolism and Pharmaceutical Analysis, College of Pharmaceutical Science, Zhejiang University, Hangzhou, Zhejiang 310058, China
| | - Su Zeng
- Institute of Drug Metabolism and Pharmaceutical Analysis, College of Pharmaceutical Science, Zhejiang University, Hangzhou, Zhejiang 310058, China
| | - Hui Liu
- Sir Run Run Shaw Hospital, School of Medicine, Zhejiang University, Hangzhou, Zhejiang 310020, China
| | - Sheng Cai
- Institute of Drug Metabolism and Pharmaceutical Analysis, College of Pharmaceutical Science, Zhejiang University, Hangzhou, Zhejiang 310058, China
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Previtali SC. Peripheral Nerve Development and the Pathogenesis of Peripheral Neuropathy: the Sorting Point. Neurotherapeutics 2021; 18:2156-2168. [PMID: 34244926 PMCID: PMC8804061 DOI: 10.1007/s13311-021-01080-z] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/26/2021] [Indexed: 12/12/2022] Open
Abstract
Nerve development requires a coordinated sequence of events and steps to be accomplished for the generation of functional peripheral nerves to convey sensory and motor signals. Any abnormality during development may result in pathological structure and function of the nerve, which evolves in peripheral neuropathy. In this review, we will briefly describe different steps of nerve development while we will mostly focus on the molecular mechanisms involved in radial sorting of axons, one of these nerve developmental steps. We will summarize current knowledge of molecular pathways so far reported in radial sorting and their possible interactions. Finally, we will describe how disruption of these pathways may result in human neuropathies.
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Affiliation(s)
- Stefano C Previtali
- Neuromuscular Repair Unit, InSpe (Institute of Experimental Neurology) and Division of Neuroscience, IRCCS San Raffaele Scientific Institute, Milan, Italy.
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17
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Felice KJ, Whitaker CH, Khorasanizadeh S. Diagnostic yield of advanced genetic testing in patients with hereditary neuropathies: A retrospective single-site study. Muscle Nerve 2021; 64:454-461. [PMID: 34232518 DOI: 10.1002/mus.27368] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2020] [Revised: 06/29/2021] [Accepted: 07/04/2021] [Indexed: 11/09/2022]
Abstract
INTRODUCTION/AIMS Advanced genetic testing including next-generation sequencing (AGT/NGS) has facilitated DNA testing in the clinical setting and greatly expanded new gene discovery for the Charcot-Marie-Tooth neuropathies and other hereditary neuropathies (CMT/HN). Herein, we report AGT/NGS results, clinical findings, and diagnostic yield in a cohort of CMT/HN patients evaluated at our neuropathy care center. METHODS We reviewed the medical records of all patients with suspected CMT/HN who underwent AGT/NGS at the Hospital for Special Care from January 2017 through January 2020. Patients with variants reported as pathogenic or likely pathogenic were included for further clinical review. RESULTS We ordered AGT/NGS on 108 patients with suspected CMT/HN. Of these, pathogenic or likely pathogenic variants were identified in 17 patients (diagnostic yield, 15.7%), including 6 (35%) with PMP22 duplications; 3 (18%) with MPZ variants; 2 (12%) with MFN2 variants; and 1 each with NEFL, IGHMBP2, GJB1, BSCL2, DNM2, and TTR variants. Diagnostic yield increased to 31.0% for patients with a positive family history. DISCUSSION AGT/NGS panels can provide specific genetic diagnoses for a subset of patients with CMT/HN disorders, which improves disease and genetic counseling and prepares patients for disease-focused therapies. Despite these advancements, many patients with known or suspected CMT/HN disorders remain without a specific genetic diagnosis. Continued advancements in genetic testing, such as multiomic technology and better understanding of genotype-phenotype correlation, will further improve detection rates for patients with suspected CMT/HN disorders.
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Affiliation(s)
- Kevin J Felice
- Department of Neuromuscular Medicine, Hospital for Special Care, New Britain, Connecticut, USA
| | - Charles H Whitaker
- Department of Neuromuscular Medicine, Hospital for Special Care, New Britain, Connecticut, USA
| | - Sadaf Khorasanizadeh
- Department of Neuromuscular Medicine, Hospital for Special Care, New Britain, Connecticut, USA
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18
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Aishwarya R, Abdullah CS, Morshed M, Remex NS, Bhuiyan MS. Sigmar1's Molecular, Cellular, and Biological Functions in Regulating Cellular Pathophysiology. Front Physiol 2021; 12:705575. [PMID: 34305655 PMCID: PMC8293995 DOI: 10.3389/fphys.2021.705575] [Citation(s) in RCA: 34] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2021] [Accepted: 06/07/2021] [Indexed: 12/11/2022] Open
Abstract
The Sigma 1 receptor (Sigmar1) is a ubiquitously expressed multifunctional inter-organelle signaling chaperone protein playing a diverse role in cellular survival. Recessive mutation in Sigmar1 have been identified as a causative gene for neuronal and neuromuscular disorder. Since the discovery over 40 years ago, Sigmar1 has been shown to contribute to numerous cellular functions, including ion channel regulation, protein quality control, endoplasmic reticulum-mitochondrial communication, lipid metabolism, mitochondrial function, autophagy activation, and involved in cellular survival. Alterations in Sigmar1’s subcellular localization, expression, and signaling has been implicated in the progression of a wide range of diseases, such as neurodegenerative diseases, ischemic brain injury, cardiovascular diseases, diabetic retinopathy, cancer, and drug addiction. The goal of this review is to summarize the current knowledge of Sigmar1 biology focusing the recent discoveries on Sigmar1’s molecular, cellular, pathophysiological, and biological functions.
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Affiliation(s)
- Richa Aishwarya
- Department of Molecular and Cellular Physiology, Louisiana State University Health Sciences Center-Shreveport, Shreveport, LA, United States
| | - Chowdhury S Abdullah
- Department of Pathology and Translational Pathobiology, Louisiana State University Health Sciences Center-Shreveport, Shreveport, LA, United States
| | - Mahboob Morshed
- Department of Pathology and Translational Pathobiology, Louisiana State University Health Sciences Center-Shreveport, Shreveport, LA, United States
| | - Naznin Sultana Remex
- Department of Molecular and Cellular Physiology, Louisiana State University Health Sciences Center-Shreveport, Shreveport, LA, United States
| | - Md Shenuarin Bhuiyan
- Department of Molecular and Cellular Physiology, Louisiana State University Health Sciences Center-Shreveport, Shreveport, LA, United States.,Department of Pathology and Translational Pathobiology, Louisiana State University Health Sciences Center-Shreveport, Shreveport, LA, United States
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Villar-Quiles RN, Le VT, Leonard-Louis S, Trang NT, Huong NT, Laddada L, Francou B, Maisonobe T, Azzedine H, Stojkovic T. Leukoencephalopathy and conduction blocks in PLEKHG5-associated intermediate CMT disease. Neuromuscul Disord 2021; 31:756-764. [PMID: 34244018 DOI: 10.1016/j.nmd.2021.06.004] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2021] [Revised: 06/03/2021] [Accepted: 06/07/2021] [Indexed: 02/05/2023]
Abstract
Biallelic variants in PLEKHG5 have been reported so far associated with different clinical phenotypes including Lower motor neuron disease (LMND) [also known as distal hereditary motor neuropathies (dHMN or HMN) or distal spinal muscular atrophy (DSMA4)] and intermediate Charcot-Marie-Tooth disease (CMT). We report four patients from two families presenting with intermediate CMT and atypical clinical and para-clinical findings. Patients presented with predominant distal weakness with none or mild sensory involvement and remain ambulant at last examination (22-36 years). Nerve conduction studies revealed, in all patients, intermediate motor nerve conduction velocities, reduced sensory amplitudes and multiple conduction blocks in upper limbs, outside of typical nerve compression sites. CK levels were strikingly elevated (1611-3867 U/L). CSF protein content was mildly elevated in two patients. Diffuse bilateral white matter lesions were detected in one patient. Genetic analysis revealed three novel frameshift variants c.1835_1860del and c.2308del (family 1) and c.104del (family 2). PLEKHG5-associated disease ranges from pure motor phenotypes with predominantly proximal involvement to intermediate CMT with predominant distal motor involvement and mild sensory symptoms. Leukoencephalopathy, elevated CK levels and the presence of conduction blocks associated with intermediate velocities in NCS are part of the phenotype and may arise suspicion of the disease, thus avoiding misdiagnosis and unnecessary therapeutics in these patients.
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Affiliation(s)
- Rocio-Nur Villar-Quiles
- Reference Center for Neuromuscular Disorders, APHP(,) Pitié-Salpêtrière Hospital, Paris, France; Centre de Recherche en Myologie, GH Pitié-Salpêtrière, Sorbonne Université-Inserm UMRS974, Paris(,) France
| | - Van Thuy Le
- Neurology department, Hanoi Medical University Hospital, Hanoi, Viet Nam
| | - Sarah Leonard-Louis
- Reference Center for Neuromuscular Disorders, APHP(,) Pitié-Salpêtrière Hospital, Paris, France
| | - Nguyen Thi Trang
- Genetics department, Hanoi Medical University Hospital, Hanoi Medical University Hanoi, Viet Nam
| | - Nguyen Thi Huong
- Neurology department, Hanoi Medical University Hospital, Hanoi, Viet Nam; Vinmec International Hospital, Hanoi, Viet Nam
| | - Lilia Laddada
- Department of Molecular Genetics Pharmacogenomics and Hormonology, APHP, Bicêtre Hospital, Paris, France; Plateforme d'expertise maladies rares AP-HP. Université Paris-Saclay(,) Le Kremlin Bicêtre(,) France
| | - Bruno Francou
- Department of Molecular Genetics Pharmacogenomics and Hormonology, APHP, Bicêtre Hospital, Paris, France
| | - Thierry Maisonobe
- Department of Neurophysiology, APHP, Hôpital Pitié Salpêtrière, Paris, France
| | - Hamid Azzedine
- Department of Pathology and Neuropathology, AMC, Amsterdam, Netherlands
| | - Tanya Stojkovic
- Reference Center for Neuromuscular Disorders, APHP(,) Pitié-Salpêtrière Hospital, Paris, France; Centre de Recherche en Myologie, GH Pitié-Salpêtrière, Sorbonne Université-Inserm UMRS974, Paris(,) France.
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Aruta F, Severi D, Iovino A, Spina E, Barghigiani M, Ruggiero L, Iodice R, Santorelli FM, Manganelli F, Tozza S. Proximal weakness involvement in the first Italian case of Charcot-Marie-Tooth 2CC harboring a novel frameshift variant in NEFH. J Peripher Nerv Syst 2021; 26:231-234. [PMID: 33987933 DOI: 10.1111/jns.12454] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2021] [Revised: 05/06/2021] [Accepted: 05/08/2021] [Indexed: 12/13/2022]
Abstract
Charcot-Marie-Tooth (CMT) diseases are a clinically and genetically heterogeneous group of disorders. Different variants in the neurofilament heavy chain (NEFH) gene have been described to cause the CMT2CC subtype. Here we report the first Italian patient affected by CMT2CC, harboring a novel variant in NEFH. In describing our patient, we also reviewed previously CMT2CC individuals, and suggested to consider NEFH variant if patients have an axonal sensory-motor neuropathy with a prominent proximal muscles involvement with early requirement of walking aids or wheelchair, remembering a motor neuron disorder.
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Affiliation(s)
- Francesco Aruta
- Department of Neuroscience, Reproductive and Odontostomatological Science, University of Naples "Federico II", Naples, Italy
| | - Daniele Severi
- Department of Neuroscience, Reproductive and Odontostomatological Science, University of Naples "Federico II", Naples, Italy
| | - Aniello Iovino
- Department of Neuroscience, Reproductive and Odontostomatological Science, University of Naples "Federico II", Naples, Italy
| | - Emanuele Spina
- Department of Neuroscience, Reproductive and Odontostomatological Science, University of Naples "Federico II", Naples, Italy
| | | | - Lucia Ruggiero
- Department of Neuroscience, Reproductive and Odontostomatological Science, University of Naples "Federico II", Naples, Italy
| | - Rosa Iodice
- Department of Neuroscience, Reproductive and Odontostomatological Science, University of Naples "Federico II", Naples, Italy
| | | | - Fiore Manganelli
- Department of Neuroscience, Reproductive and Odontostomatological Science, University of Naples "Federico II", Naples, Italy
| | - Stefano Tozza
- Department of Neuroscience, Reproductive and Odontostomatological Science, University of Naples "Federico II", Naples, Italy
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21
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Abstract
PURPOSE OF REVIEW Hereditary motor neuropathies (HMN) comprise a broad genotypic and phenotypic spectrum of rare, progressively disabling diseases manifesting with length-dependent muscle weakness and atrophy. To date, more than half of the cases cannot be genetically explained. To provide symptomatic and disease-modifying treatments in the future, a better understanding of disease mechanisms is required. RECENT FINDINGS By whole exome and genome sequencing, the discovery of several novel genes (SCO2, TDRKH, SPTAN1, CADM3, and SORD) involved in the pathogenesis of HMN has now relevantly changed the pathophysiological knowledge. This recent success in causative understanding has mainly been driven by the development of functional models including cell culture, animal, and patient-derived induced pluripotent stem cell platforms. These models have an important impact on therapeutic advances including broader approaches to prevent or reverse axonal degeneration and individualized gene silencing attempts using sequence-specific RNA degradation mechanisms. SUMMARY In rare diseases such as HMN, the recent development of genetic sequencing and data interpretation methods has enabled a broader diagnostic approach, whereas treatment strategies are becoming more individualized. Significant milestones have been reached in the discovery of new genes, the establishment of functional disease models, and the preclinical development of mechanistic-based therapies.
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22
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Neuropathy-causing TRPV4 mutations disrupt TRPV4-RhoA interactions and impair neurite extension. Nat Commun 2021; 12:1444. [PMID: 33664271 PMCID: PMC7933254 DOI: 10.1038/s41467-021-21699-y] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2020] [Accepted: 02/02/2021] [Indexed: 12/19/2022] Open
Abstract
TRPV4 is a cell surface-expressed calcium-permeable cation channel that mediates cell-specific effects on cellular morphology and function. Dominant missense mutations of TRPV4 cause distinct, tissue-specific diseases, but the pathogenic mechanisms are unknown. Mutations causing peripheral neuropathy localize to the intracellular N-terminal domain whereas skeletal dysplasia mutations are in multiple domains. Using an unbiased screen, we identified the cytoskeletal remodeling GTPase RhoA as a TRPV4 interactor. TRPV4-RhoA binding occurs via the TRPV4 N-terminal domain, resulting in suppression of TRPV4 channel activity, inhibition of RhoA activation, and extension of neurites in vitro. Neuropathy but not skeletal dysplasia mutations disrupt TRPV4-RhoA binding and cytoskeletal outgrowth. However, inhibition of RhoA restores neurite length in vitro and in a fly model of TRPV4 neuropathy. Together these results identify RhoA as a critical mediator of TRPV4-induced cell structure changes and suggest that disruption of TRPV4-RhoA binding may contribute to tissue-specific toxicity of TRPV4 neuropathy mutations. TRPV4 dominant mutations cause neuropathy. Here, the authors show that TRPV4 binds and interacts with RhoA, modulating the actin cytoskeleton. Neuropathy-causing mutations of TRPV4 disrupt this complex, leading to RhoA activation and impairment of neurite extension in cultured cells and flies.
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23
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Frasquet M, Rojas-García R, Argente-Escrig H, Vázquez-Costa JF, Muelas N, Vílchez JJ, Sivera R, Millet E, Barreiro M, Díaz-Manera J, Turon-Sans J, Cortés-Vicente E, Querol L, Ramírez-Jiménez L, Martínez-Rubio D, Sánchez-Monteagudo A, Espinós C, Sevilla T, Lupo V. Distal hereditary motor neuropathies: Mutation spectrum and genotype-phenotype correlation. Eur J Neurol 2021; 28:1334-1343. [PMID: 33369814 DOI: 10.1111/ene.14700] [Citation(s) in RCA: 41] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2020] [Revised: 11/28/2020] [Accepted: 12/17/2020] [Indexed: 01/12/2023]
Abstract
BACKGROUND AND PURPOSE Distal hereditary motor neuropathies (dHMNs) are a heterogeneous group of disorders characterized by degeneration of the motor component of peripheral nerves. Currently, only 15% to 32.5% of patients with dHMN are characterized genetically. Additionally, the prevalence of these genetic disorders is not well known. Recently, biallelic mutations in the sorbitol dehydrogenase gene (SORD) have been identified as a cause of dHMN, with an estimated frequency in undiagnosed cases of up to 10%. METHODS In the present study, we included 163 patients belonging to 108 different families who were diagnosed with a dHMN and who underwent a thorough genetic screening that included next-generation sequencing and subsequent Sanger sequencing of SORD. RESULTS Most probands were sporadic cases (62.3%), and the most frequent age of onset of symptoms was 2 to 10 years (28.8%). A genetic diagnosis was achieved in 37/108 (34.2%) families and 78/163 (47.8%) of all patients. The most frequent cause of distal hereditary motor neuropathies were mutations in HSPB1 (10.4%), GARS1 (9.8%), BICD2 (8.0%), and DNAJB2 (6.7%) genes. In addition, 3.1% of patients were found to be carriers of biallelic mutations in SORD. Mutations in another seven genes were also identified, although they were much less frequent. Eight new pathogenic mutations were detected, and 17 patients without a definite genetic diagnosis carried variants of uncertain significance. The calculated minimum prevalence of dHMN was 2.3 per 100,000 individuals. CONCLUSIONS This study confirms the genetic heterogeneity of dHMN and that biallelic SORD mutations are a cause of dHMN in different populations.
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Affiliation(s)
- Marina Frasquet
- Neuromuscular Diseases Unit, Department of Neurology, Hospital Universitari i Politècnic La Fe, Valencia, Spain.,Neuromuscular and Ataxias Research Group, Instituto de Investigación Sanitaria La Fe, Valencia, Spain.,Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER) Spain, Valencia, Spain
| | - Ricard Rojas-García
- Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER) Spain, Valencia, Spain.,Neuromuscular Diseases Unit, Department of Neurology, Hospital de la Santa Creu i Sant Pau, Barcelona, Spain.,Universitat Autònoma de Barcelona, Barcelona, Spain
| | - Herminia Argente-Escrig
- Neuromuscular and Ataxias Research Group, Instituto de Investigación Sanitaria La Fe, Valencia, Spain.,Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER) Spain, Valencia, Spain
| | - Juan Francisco Vázquez-Costa
- Neuromuscular Diseases Unit, Department of Neurology, Hospital Universitari i Politècnic La Fe, Valencia, Spain.,Neuromuscular and Ataxias Research Group, Instituto de Investigación Sanitaria La Fe, Valencia, Spain.,Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER) Spain, Valencia, Spain.,Department of Medicine, Universitat de València, Valencia, Spain
| | - Nuria Muelas
- Neuromuscular Diseases Unit, Department of Neurology, Hospital Universitari i Politècnic La Fe, Valencia, Spain.,Neuromuscular and Ataxias Research Group, Instituto de Investigación Sanitaria La Fe, Valencia, Spain.,Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER) Spain, Valencia, Spain
| | - Juan Jesús Vílchez
- Neuromuscular and Ataxias Research Group, Instituto de Investigación Sanitaria La Fe, Valencia, Spain.,Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER) Spain, Valencia, Spain
| | - Rafael Sivera
- Department of Neurology, Hospital Francesc de Borja, Gandía, Spain
| | - Elvira Millet
- Department of Clinical Neurophysiology, Hospital Universitari i Politècnic La Fe, Valencia, Spain
| | - Marisa Barreiro
- Neuromuscular and Ataxias Research Group, Instituto de Investigación Sanitaria La Fe, Valencia, Spain
| | - Jordi Díaz-Manera
- Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER) Spain, Valencia, Spain.,Neuromuscular Diseases Unit, Department of Neurology, Hospital de la Santa Creu i Sant Pau, Barcelona, Spain.,Universitat Autònoma de Barcelona, Barcelona, Spain
| | - Janina Turon-Sans
- Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER) Spain, Valencia, Spain.,Neuromuscular Diseases Unit, Department of Neurology, Hospital de la Santa Creu i Sant Pau, Barcelona, Spain.,Universitat Autònoma de Barcelona, Barcelona, Spain
| | - Elena Cortés-Vicente
- Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER) Spain, Valencia, Spain.,Neuromuscular Diseases Unit, Department of Neurology, Hospital de la Santa Creu i Sant Pau, Barcelona, Spain.,Universitat Autònoma de Barcelona, Barcelona, Spain
| | - Luis Querol
- Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER) Spain, Valencia, Spain.,Neuromuscular Diseases Unit, Department of Neurology, Hospital de la Santa Creu i Sant Pau, Barcelona, Spain.,Universitat Autònoma de Barcelona, Barcelona, Spain
| | - Laura Ramírez-Jiménez
- Department of Genomics and Translational Genetics, Centro de Investigación Príncipe Felipe (CIPF), Valencia, Spain
| | - Dolores Martínez-Rubio
- Unit of Genetics and Genomics of Neuromuscular and Neurodegenerative Disorders, Centro de Investigación Príncipe Felipe (CIPF), Valencia, Spain.,Rare Diseases Joint Units, INCLIVA and IIS La Fe-CIPF, Valencia, Spain
| | - Ana Sánchez-Monteagudo
- Unit of Genetics and Genomics of Neuromuscular and Neurodegenerative Disorders, Centro de Investigación Príncipe Felipe (CIPF), Valencia, Spain.,Rare Diseases Joint Units, INCLIVA and IIS La Fe-CIPF, Valencia, Spain
| | - Carmen Espinós
- Unit of Genetics and Genomics of Neuromuscular and Neurodegenerative Disorders, Centro de Investigación Príncipe Felipe (CIPF), Valencia, Spain.,Rare Diseases Joint Units, INCLIVA and IIS La Fe-CIPF, Valencia, Spain
| | - Teresa Sevilla
- Neuromuscular Diseases Unit, Department of Neurology, Hospital Universitari i Politècnic La Fe, Valencia, Spain.,Neuromuscular and Ataxias Research Group, Instituto de Investigación Sanitaria La Fe, Valencia, Spain.,Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER) Spain, Valencia, Spain.,Department of Medicine, Universitat de València, Valencia, Spain
| | - Vincenzo Lupo
- Unit of Genetics and Genomics of Neuromuscular and Neurodegenerative Disorders, Centro de Investigación Príncipe Felipe (CIPF), Valencia, Spain.,Rare Diseases Joint Units, INCLIVA and IIS La Fe-CIPF, Valencia, Spain
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Grecu N, Villa L, Cavalli M, Ristaino A, Choumert A, Butori C, Salviati L, Puma A, Krahn M, Cerino M, Sacconi S. Motor axonal neuropathy associated with GNE mutations. Muscle Nerve 2020; 63:396-401. [PMID: 33094863 DOI: 10.1002/mus.27102] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2020] [Revised: 10/15/2020] [Accepted: 10/18/2020] [Indexed: 12/12/2022]
Abstract
BACKGROUND Mutations in the GNE gene have been so far described as predominantly associated with distal lower-limb myopathies. Recent reports describe mutations in this gene in patients with peripheral neuropathy and motor neuron disease. METHODS We describe three patients displaying motor neuropathy in association with GNE mutations. Clinical, electrophysiological, imaging, pathological, and genetic data are presented in a retrospective manner. RESULTS The three patients had different phenotypes, ranging from mildly progressive lower limb weakness to a rapidly progressive 4-limb weakness. Genetic testing revealed GNE gene mutations in all patients; of those mutations, p.(His186Arg) has not been previously reported. All patients showed evidence of axonal motor nerve involvement on electrodiagnostic examination and/or muscle biopsy. CONCLUSIONS Nerve involvement associated with GNE gene mutations may be an underdiagnosed pathology and may influence clinical presentation and disease progression.
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Affiliation(s)
- Nicolae Grecu
- Côte d'Azur University, Peripheral Nervous System and Muscle Department, Nice University Hospital, Nice, France
| | - Luisa Villa
- Côte d'Azur University, Peripheral Nervous System and Muscle Department, Nice University Hospital, Nice, France
| | - Michele Cavalli
- Department of Biomedical Sciences for Health, University of Milan, Milan, Italy
| | - Antoine Ristaino
- Côte d'Azur University, Peripheral Nervous System and Muscle Department, Nice University Hospital, Nice, France
| | - Ariane Choumert
- Rare Neurological Diseases Department, La Réunion University Hospital, Saint-Pierre, France
| | - Catherine Butori
- Clinical and Experimental Laboratory, Nice University Hospital, Nice, France
| | - Leonardo Salviati
- Department of Women and Children's Health, University of Padova, Padova, Italy
| | - Angela Puma
- Côte d'Azur University, Peripheral Nervous System and Muscle Department, Nice University Hospital, Nice, France
| | - Martin Krahn
- Aix-Marseille Université, Inserm, U1251-MMG, Marseille Medical Genetics, Marseille, France
- Département de Génétique Médicale, APHM, Hôpital Timone Enfants, Marseille, France
| | - Mathieu Cerino
- Aix-Marseille Université, Inserm, U1251-MMG, Marseille Medical Genetics, Marseille, France
- Département de Génétique Médicale, APHM, Hôpital Timone Enfants, Marseille, France
- APHM, Hôpital de la Conception, Laboratoire de Biochimie, Marseille, France
| | - Sabrina Sacconi
- Côte d'Azur University, Peripheral Nervous System and Muscle Department, Nice University Hospital, Nice, France
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25
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Argente-Escrig H, Burns J, Donlevy G, Frasquet M, Cornett K, Sevilla T, Menezes MP. Clinical, Genetic, and Disability Profile of Pediatric Distal Hereditary Motor Neuropathy. Neurology 2020; 96:e423-e432. [PMID: 33067402 DOI: 10.1212/wnl.0000000000011054] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2020] [Accepted: 09/01/2020] [Indexed: 11/15/2022] Open
Abstract
OBJECTIVE To describe the clinical, genetic, and disability profile of pediatric distal hereditary motor neuropathy (dHMN) and to determine the utility of an outcome measure validated for children with Charcot-Marie-Tooth disease (CMT) in assessing disability in this cohort. METHODS We reviewed the clinical, neurophysiologic, and disability data on individuals with dHMN, evaluated before the age of 20 years, at 2 tertiary neuromuscular clinics in Australia and Spain. Disability was assessed annually with the CMT Pediatric Scale (CMTPedS) in a subset of individuals. RESULTS Twenty-two children (13 female) from 19 families were included. Fourteen individuals were symptomatic in the first year of life. Intellectual disability was present in 6 individuals; upper motor neuron signs were seen in 8. Pathogenic variants were found in 9 families, more frequently in BICD2 (BICD2-4, DYNC1H1-2, MFN2-2, GARS-1). A novel pathogenic variant in the GARS gene was detected and characterized phenotypically. Disability was moderate on the CMTPedS (mean [SD] 18.2 [6.3], n = 16), with balance and long jump being the most affected and sensation items and grip strength the least affected. Over 1 year, the CMTPedS total score deteriorated, on average 1.5 points (SD 3.7) or 9% (n = 12), with significant variability in the rate of progression within the cohort. CONCLUSIONS The genetic profile of pediatric dHMN is different from that identified in adult cohorts. This study has identified distinct functional limitations for the CMTPedS in children and adolescents with dHMN.
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Affiliation(s)
- Herminia Argente-Escrig
- From the T.Y. Nelson Department of Neurology and Neurosurgery (M.P.M.), The Children's Hospital at Westmead, NSW; University of Sydney School of Health Sciences & Children's Hospital at Westmead (J.B., G.D., K.C., M.P.M.), Sydney, Australia; Health Research Institute Hospital La Fe (H.A.-E., M.F.) and Department of Neurology (H.A.-E, M.F., T.S.), Hospital Universitari i Politècnic La Fe, Valencia, Spain; Centre for Biomedical Network Research on Rare Diseases-CIBERER (H.A.E., T.S.); and Department of Medicine (T.S.), University of Valencia, Spain
| | - Joshua Burns
- From the T.Y. Nelson Department of Neurology and Neurosurgery (M.P.M.), The Children's Hospital at Westmead, NSW; University of Sydney School of Health Sciences & Children's Hospital at Westmead (J.B., G.D., K.C., M.P.M.), Sydney, Australia; Health Research Institute Hospital La Fe (H.A.-E., M.F.) and Department of Neurology (H.A.-E, M.F., T.S.), Hospital Universitari i Politècnic La Fe, Valencia, Spain; Centre for Biomedical Network Research on Rare Diseases-CIBERER (H.A.E., T.S.); and Department of Medicine (T.S.), University of Valencia, Spain
| | - Gabrielle Donlevy
- From the T.Y. Nelson Department of Neurology and Neurosurgery (M.P.M.), The Children's Hospital at Westmead, NSW; University of Sydney School of Health Sciences & Children's Hospital at Westmead (J.B., G.D., K.C., M.P.M.), Sydney, Australia; Health Research Institute Hospital La Fe (H.A.-E., M.F.) and Department of Neurology (H.A.-E, M.F., T.S.), Hospital Universitari i Politècnic La Fe, Valencia, Spain; Centre for Biomedical Network Research on Rare Diseases-CIBERER (H.A.E., T.S.); and Department of Medicine (T.S.), University of Valencia, Spain
| | - Marina Frasquet
- From the T.Y. Nelson Department of Neurology and Neurosurgery (M.P.M.), The Children's Hospital at Westmead, NSW; University of Sydney School of Health Sciences & Children's Hospital at Westmead (J.B., G.D., K.C., M.P.M.), Sydney, Australia; Health Research Institute Hospital La Fe (H.A.-E., M.F.) and Department of Neurology (H.A.-E, M.F., T.S.), Hospital Universitari i Politècnic La Fe, Valencia, Spain; Centre for Biomedical Network Research on Rare Diseases-CIBERER (H.A.E., T.S.); and Department of Medicine (T.S.), University of Valencia, Spain
| | - Kayla Cornett
- From the T.Y. Nelson Department of Neurology and Neurosurgery (M.P.M.), The Children's Hospital at Westmead, NSW; University of Sydney School of Health Sciences & Children's Hospital at Westmead (J.B., G.D., K.C., M.P.M.), Sydney, Australia; Health Research Institute Hospital La Fe (H.A.-E., M.F.) and Department of Neurology (H.A.-E, M.F., T.S.), Hospital Universitari i Politècnic La Fe, Valencia, Spain; Centre for Biomedical Network Research on Rare Diseases-CIBERER (H.A.E., T.S.); and Department of Medicine (T.S.), University of Valencia, Spain
| | - Teresa Sevilla
- From the T.Y. Nelson Department of Neurology and Neurosurgery (M.P.M.), The Children's Hospital at Westmead, NSW; University of Sydney School of Health Sciences & Children's Hospital at Westmead (J.B., G.D., K.C., M.P.M.), Sydney, Australia; Health Research Institute Hospital La Fe (H.A.-E., M.F.) and Department of Neurology (H.A.-E, M.F., T.S.), Hospital Universitari i Politècnic La Fe, Valencia, Spain; Centre for Biomedical Network Research on Rare Diseases-CIBERER (H.A.E., T.S.); and Department of Medicine (T.S.), University of Valencia, Spain
| | - Manoj P Menezes
- From the T.Y. Nelson Department of Neurology and Neurosurgery (M.P.M.), The Children's Hospital at Westmead, NSW; University of Sydney School of Health Sciences & Children's Hospital at Westmead (J.B., G.D., K.C., M.P.M.), Sydney, Australia; Health Research Institute Hospital La Fe (H.A.-E., M.F.) and Department of Neurology (H.A.-E, M.F., T.S.), Hospital Universitari i Politècnic La Fe, Valencia, Spain; Centre for Biomedical Network Research on Rare Diseases-CIBERER (H.A.E., T.S.); and Department of Medicine (T.S.), University of Valencia, Spain.
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26
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Abstract
Abstract
Inherited peripheral neuropathy is the most common hereditary neuromuscular disease with a prevalence of about 1:2,500. The most frequent form is Charcot-Marie-Tooth disease (CMT, or hereditary motor and sensory neuropathy [HMSN]). Other clinical entities are hereditary neuropathy with liability to pressure palsies (HNPP), distal hereditary motor neuropathies (dHMN), and hereditary sensory and autonomic neuropathies (HSAN). With the exception of HNPP, which is almost always caused by defects of the PMP22 gene, all other forms show genetic heterogeneity with altogether more than 100 genes involved. Mutation detection rates vary considerably, reaching up to 80 % in demyelinating CMT (CMT1) but are still as low as 10–30 % in axonal CMT (CMT2), dHMN, and HSAN. Based on current information, analysis of only four genes (PMP22, GJB1, MPZ, MFN2) identifies 80–90 % of CMT-causing mutations that can be detected in all known disease genes. For the remaining patients, parallel analysis of multiple neuropathy genes using next-generation sequencing is now replacing phenotype-oriented multistep gene-by-gene sequencing. Such approaches tend to generate a wealth of genetic information that requires comprehensive evaluation of the pathogenic relevance of identified variants. In this review, we present current classification systems, specific phenotypic clues, and diagnostic yields in the different subgroups of hereditary CMT and motor neuropathies.
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27
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Kalasova I, Hailstone R, Bublitz J, Bogantes J, Hofmann W, Leal A, Hanzlikova H, Caldecott KW. Pathological mutations in PNKP trigger defects in DNA single-strand break repair but not DNA double-strand break repair. Nucleic Acids Res 2020; 48:6672-6684. [PMID: 32504494 PMCID: PMC7337934 DOI: 10.1093/nar/gkaa489] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2020] [Revised: 04/30/2020] [Accepted: 06/04/2020] [Indexed: 12/20/2022] Open
Abstract
Hereditary mutations in polynucleotide kinase-phosphatase (PNKP) result in a spectrum of neurological pathologies ranging from neurodevelopmental dysfunction in microcephaly with early onset seizures (MCSZ) to neurodegeneration in ataxia oculomotor apraxia-4 (AOA4) and Charcot-Marie-Tooth disease (CMT2B2). Consistent with this, PNKP is implicated in the repair of both DNA single-strand breaks (SSBs) and DNA double-strand breaks (DSBs); lesions that can trigger neurodegeneration and neurodevelopmental dysfunction, respectively. Surprisingly, however, we did not detect a significant defect in DSB repair (DSBR) in primary fibroblasts from PNKP patients spanning the spectrum of PNKP-mutated pathologies. In contrast, the rate of SSB repair (SSBR) is markedly reduced. Moreover, we show that the restoration of SSBR in patient fibroblasts collectively requires both the DNA kinase and DNA phosphatase activities of PNKP, and the fork-head associated (FHA) domain that interacts with the SSBR protein, XRCC1. Notably, however, the two enzymatic activities of PNKP appear to affect different aspects of disease pathology, with reduced DNA phosphatase activity correlating with neurodevelopmental dysfunction and reduced DNA kinase activity correlating with neurodegeneration. In summary, these data implicate reduced rates of SSBR, not DSBR, as the source of both neurodevelopmental and neurodegenerative pathology in PNKP-mutated disease, and the extent and nature of this reduction as the primary determinant of disease severity.
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Affiliation(s)
- Ilona Kalasova
- Department of Genome Dynamics, Institute of Molecular Genetics of the Czech Academy of Sciences, Prague 4, 142 20, Czech Republic
| | - Richard Hailstone
- Genome Damage and Stability Centre, University of Sussex, Falmer, Brighton BN1 9RQ, UK
| | - Janin Bublitz
- Department of Human Genetics, Hannover Medical School, Hannover, Germany
| | - Jovel Bogantes
- Servicio de Cirugía Reconstructiva, Hospital Rafael Ángel Calderón Guardia, Caja Costarricense de Seguro Social, San José, Costa Rica
| | - Winfried Hofmann
- Department of Human Genetics, Hannover Medical School, Hannover, Germany
| | - Alejandro Leal
- Section of Genetics and Biotechnology, School of Biology, University of Costa Rica, San José, Costa Rica
| | - Hana Hanzlikova
- Department of Genome Dynamics, Institute of Molecular Genetics of the Czech Academy of Sciences, Prague 4, 142 20, Czech Republic.,Genome Damage and Stability Centre, University of Sussex, Falmer, Brighton BN1 9RQ, UK
| | - Keith W Caldecott
- Department of Genome Dynamics, Institute of Molecular Genetics of the Czech Academy of Sciences, Prague 4, 142 20, Czech Republic.,Genome Damage and Stability Centre, University of Sussex, Falmer, Brighton BN1 9RQ, UK
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28
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Kiernan MC. The Journal of Neurology, Neurosurgery and Psychiatry centenary milestone award 2020. J Neurol Neurosurg Psychiatry 2020; 91:677. [PMID: 32123039 DOI: 10.1136/jnnp-2020-322976] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/06/2020] [Accepted: 02/06/2020] [Indexed: 12/22/2022]
Affiliation(s)
- Matthew C Kiernan
- Bushell Chair of Neurology, Brain and Mind Centre, University of Sydney, Sydney, New South Wales, Australia .,Neurology, Royal Prince Alfred Hospital, Camperdown, New South Wales, Australia
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29
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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.
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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
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30
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Marcos AT, Martín‐Doncel E, Morejón‐García P, Marcos‐Alcalde I, Gómez‐Puertas P, Segura‐Puimedon M, Armengol L, Navarro‐Pando JM, Lazo PA. VRK1 (Y213H) homozygous mutant impairs Cajal bodies in a hereditary case of distal motor neuropathy. Ann Clin Transl Neurol 2020; 7:808-818. [PMID: 32365420 PMCID: PMC7261760 DOI: 10.1002/acn3.51050] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2020] [Revised: 03/27/2020] [Accepted: 03/31/2020] [Indexed: 12/12/2022] Open
Abstract
BACKGROUND Distal motor neuropathies with a genetic origin have a heterogeneous clinical presentation with overlapping features affecting distal nerves and including spinal muscular atrophies and amyotrophic lateral sclerosis. This indicates that their genetic background is heterogeneous. PATIENT AND METHODS In this work, we have identified and characterized the genetic and molecular base of a patient with a distal sensorimotor neuropathy of unknown origin. For this study, we performed whole-exome sequencing, molecular modelling, cloning and expression of mutant gene, and biochemical and cell biology analysis of the mutant protein. RESULTS A novel homozygous recessive mutation in the human VRK1 gene, coding for a chromatin kinase, causing a substitution (c.637T > C; p.Tyr213His) in exon 8, was detected in a patient presenting since childhood a progressive distal sensorimotor neuropathy and spinal muscular atrophy syndrome, with normal intellectual development. Molecular modelling predicted this mutant VRK1 has altered the kinase activation loop by disrupting its interaction with the C-terminal regulatory region. The p.Y213H mutant protein has a reduced kinase activity with different substrates, including histones H3 and H2AX, proteins involved in DNA damage responses, such as p53 and 53BP1, and coilin, the scaffold for Cajal bodies. The mutant VRK1(Y213H) protein is unable to rescue the formation of Cajal bodies assembled on coilin, in the absence of wild-type VRK1. CONCLUSION The VRK1(Y213H) mutant protein alters the activation loop, impairs the kinase activity of VRK1 causing a functional insufficiency that impairs the formation of Cajal bodies assembled on coilin, a protein that regulates SMN1 and Cajal body formation.
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Affiliation(s)
- Ana T. Marcos
- Unidad de GenéticaInstituto para el Estudio de la Biología de la Reproducción Humana (INEBIR)SevillaSpain
| | - Elena Martín‐Doncel
- Molecular Mechanisms of Cancer ProgramInstituto de Biología Molecular y Celular del CáncerConsejo Superior de Investigaciones Científicas (CSIC)Universidad de SalamancaSalamancaSpain
- Instituto de Investigación Biomédica de Salamanca (IBSAL)Hospital Universitario de SalamancaSalamancaSpain
| | - Patricia Morejón‐García
- Molecular Mechanisms of Cancer ProgramInstituto de Biología Molecular y Celular del CáncerConsejo Superior de Investigaciones Científicas (CSIC)Universidad de SalamancaSalamancaSpain
- Instituto de Investigación Biomédica de Salamanca (IBSAL)Hospital Universitario de SalamancaSalamancaSpain
| | - Iñigo Marcos‐Alcalde
- Molecular Modelling GroupCentro de Biología Molecular “Severo Ochoa”CSIC‐Universidad Autónoma de Madrid, CantoblancoMadridSpain
- School of Experimental SciencesBiosciences Research InstituteUniversidad Francisco de VitoriaPozuelo de Alarcón, MadridSpain
| | - Paulino Gómez‐Puertas
- Molecular Modelling GroupCentro de Biología Molecular “Severo Ochoa”CSIC‐Universidad Autónoma de Madrid, CantoblancoMadridSpain
| | - María Segura‐Puimedon
- Quantitative Genomic Medicine Laboratories, qGenomicsEspluges de LlobregatBarcelonaSpain
| | - Lluis Armengol
- Quantitative Genomic Medicine Laboratories, qGenomicsEspluges de LlobregatBarcelonaSpain
| | - José M. Navarro‐Pando
- Unidad de GenéticaInstituto para el Estudio de la Biología de la Reproducción Humana (INEBIR)SevillaSpain
- Cátedra de Reproducción y Genética HumanaFacultad de Ciencias de la SaludUniversidad Europea del AtlánticoSantanderSpain
- Fundación Universitaria Iberoamericana (FUNIBER)BarcelonaSpain
| | - Pedro A. Lazo
- Molecular Mechanisms of Cancer ProgramInstituto de Biología Molecular y Celular del CáncerConsejo Superior de Investigaciones Científicas (CSIC)Universidad de SalamancaSalamancaSpain
- Instituto de Investigación Biomédica de Salamanca (IBSAL)Hospital Universitario de SalamancaSalamancaSpain
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31
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Greenbaum L, Barel O, Nikitin V, Hersalis-Eldar A, Kol N, Reznik-Wolf H, Dominissini D, Pras E, Dori A. Identification of a homozygous VRK1 mutation in two patients with adult-onset distal hereditary motor neuropathy. Muscle Nerve 2020; 61:395-400. [PMID: 31837156 DOI: 10.1002/mus.26779] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2019] [Revised: 12/04/2019] [Accepted: 12/07/2019] [Indexed: 12/13/2022]
Abstract
BACKGROUND Adult-onset hereditary motor neuropathies are caused by mutations in multiple genes. Mutations within the vaccinia-related kinase 1 (VRK1) gene were associated with a wide spectrum of recessively inherited motor neuropathies, characterized by childhood to early adulthood age of onset and an occasionally non-lower motor neuron involvement. METHODS We describe two patients with adult-onset (aged 48 and 40 years) length-dependent motor neuropathy from unrelated consanguineous families of Moroccan Jewish descent. One also demonstrated mild nocturnal respiratory difficulty and sensory symptoms. Whole-exome sequencing (WES) was performed. RESULTS A homozygous mutation in VRK1 (c.1160G>A (p.Arg387His)), shared by both patients, was identified. This rare mutation segregated with the disease in the two families, and was absent in 120 controls of Jewish Moroccan origin. CONCLUSIONS Our findings support VRK1 as a causative gene for adult-onset distal hereditary motor neuropathy, and indicate its relevance for evaluation of individuals with similar motor impairment.
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Affiliation(s)
- Lior Greenbaum
- The Danek Gertner Institute of Human Genetics, Sheba Medical Center, Tel Hashomer, Israel.,The Joseph Sagol Neuroscience Center, Sheba Medical Center, Tel Hashomer, Israel.,Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Ortal Barel
- Cancer Research Center and Wohl Institute for Translational Medicine, Sheba Medical Center, Tel Hashomer, Israel
| | - Vera Nikitin
- Department of Neurology, Sheba Medical Center, Tel Hashomer, Israel
| | | | - Nitzan Kol
- Cancer Research Center and Wohl Institute for Translational Medicine, Sheba Medical Center, Tel Hashomer, Israel
| | - Haike Reznik-Wolf
- The Danek Gertner Institute of Human Genetics, Sheba Medical Center, Tel Hashomer, Israel
| | - Dan Dominissini
- Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel.,Cancer Research Center and Wohl Institute for Translational Medicine, Sheba Medical Center, Tel Hashomer, Israel
| | - Elon Pras
- The Danek Gertner Institute of Human Genetics, Sheba Medical Center, Tel Hashomer, Israel.,Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Amir Dori
- The Joseph Sagol Neuroscience Center, Sheba Medical Center, Tel Hashomer, Israel.,Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel.,Department of Neurology, Sheba Medical Center, Tel Hashomer, Israel
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