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Higuchi Y, Ando M, Kojima F, Yuan J, Hashiguchi A, Yoshimura A, Hiramatsu Y, Nozuma S, Fukumura S, Yahikozawa H, Abe E, Toyoshima I, Sugawara M, Okamoto Y, Matsuura E, Takashima H. Dystonia and Parkinsonism in COA7-related disorders: expanding the phenotypic spectrum. J Neurol 2024; 271:419-430. [PMID: 37750949 PMCID: PMC10769979 DOI: 10.1007/s00415-023-11998-3] [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: 07/05/2023] [Revised: 09/11/2023] [Accepted: 09/13/2023] [Indexed: 09/27/2023]
Abstract
BACKGROUND AND OBJECTIVE Biallelic mutations in the COA7 gene have been associated with spinocerebellar ataxia with axonal neuropathy type 3 (SCAN3), and a notable clinical diversity has been observed. We aim to identify the genetic and phenotypic spectrum of COA7-related disorders. METHODS We conducted comprehensive genetic analyses on the COA7 gene within a large group of Japanese patients clinically diagnosed with inherited peripheral neuropathy or cerebellar ataxia. RESULTS In addition to our original report, which involved four patients until 2018, we identified biallelic variants of the COA7 gene in another three unrelated patients, and the variants were c.17A > G (p.D6G), c.115C > T (p.R39W), and c.449G > A (p.C150Y; novel). Patient 1 presented with an infantile-onset generalized dystonia without cerebellar ataxia. Despite experiencing an initial transient positive response to levodopa and deep brain stimulation, he became bedridden by the age of 19. Patient 2 presented with cerebellar ataxia, neuropathy, as well as parkinsonism, and showed a slight improvement upon levodopa administration. Dopamine transporter SPECT showed decreased uptake in the bilateral putamen in both patients. Patient 3 exhibited severe muscle weakness, respiratory failure, and feeding difficulties. A haplotype analysis of the mutation hotspot in Japan, c.17A > G (p.D6G), uncovered a common haplotype block. CONCLUSION COA7-related disorders typically encompass a spectrum of conditions characterized by a variety of major (cerebellar ataxia and axonal polyneuropathy) and minor (leukoencephalopathy, dystonia, and parkinsonism) symptoms, but may also display a dystonia-predominant phenotype. We propose that COA7 should be considered as a new causative gene for infancy-onset generalized dystonia, and COA7 gene screening is recommended for patients with unexplained dysfunctions of the central and peripheral nervous systems.
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Affiliation(s)
- Yujiro Higuchi
- Department of Neurology and Geriatrics, Kagoshima University Graduate School of Medical and Dental Sciences, 8-35-1 Sakuragaoka, Kagoshima City, Kagoshima, 890-8520, Japan
| | - Masahiro Ando
- Department of Neurology and Geriatrics, Kagoshima University Graduate School of Medical and Dental Sciences, 8-35-1 Sakuragaoka, Kagoshima City, Kagoshima, 890-8520, Japan
| | - Fumikazu Kojima
- Department of Neurology and Geriatrics, Kagoshima University Graduate School of Medical and Dental Sciences, 8-35-1 Sakuragaoka, Kagoshima City, Kagoshima, 890-8520, Japan
| | - Junhui Yuan
- Department of Neurology and Geriatrics, Kagoshima University Graduate School of Medical and Dental Sciences, 8-35-1 Sakuragaoka, Kagoshima City, Kagoshima, 890-8520, Japan
| | - Akihiro Hashiguchi
- Department of Neurology and Geriatrics, Kagoshima University Graduate School of Medical and Dental Sciences, 8-35-1 Sakuragaoka, Kagoshima City, Kagoshima, 890-8520, Japan
| | - Akiko Yoshimura
- Department of Neurology and Geriatrics, Kagoshima University Graduate School of Medical and Dental Sciences, 8-35-1 Sakuragaoka, Kagoshima City, Kagoshima, 890-8520, Japan
| | - Yu Hiramatsu
- Department of Neurology and Geriatrics, Kagoshima University Graduate School of Medical and Dental Sciences, 8-35-1 Sakuragaoka, Kagoshima City, Kagoshima, 890-8520, Japan
| | - Satoshi Nozuma
- Department of Neurology and Geriatrics, Kagoshima University Graduate School of Medical and Dental Sciences, 8-35-1 Sakuragaoka, Kagoshima City, Kagoshima, 890-8520, Japan
| | - Shinobu Fukumura
- Department of Pediatrics, Sapporo Medical University School of Medicine, Sapporo, Japan
| | | | - Erika Abe
- Department of Neurology, National Hospital Organization Akita National Hospital, Yurihonjo, Japan
| | - Itaru Toyoshima
- Department of Neurology, National Hospital Organization Akita National Hospital, Yurihonjo, Japan
| | - Masashiro Sugawara
- Department of Neurology, Akita University Graduate School of Medicine, Akita, Japan
| | - Yuji Okamoto
- Department of Neurology and Geriatrics, Kagoshima University Graduate School of Medical and Dental Sciences, 8-35-1 Sakuragaoka, Kagoshima City, Kagoshima, 890-8520, Japan
- Department of Physical Therapy, School of Health Sciences, Faculty of Medicine, Kagoshima University, Kagoshima, Japan
| | - Eiji Matsuura
- Department of Neurology and Geriatrics, Kagoshima University Graduate School of Medical and Dental Sciences, 8-35-1 Sakuragaoka, Kagoshima City, Kagoshima, 890-8520, Japan
| | - Hiroshi Takashima
- Department of Neurology and Geriatrics, Kagoshima University Graduate School of Medical and Dental Sciences, 8-35-1 Sakuragaoka, Kagoshima City, Kagoshima, 890-8520, Japan.
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Yamashiro M, Ohnari K, Higuchi Y, Hashiguchi H, Takashima H, Okada K. [A case of Charcot-Marie-Tooth disease type 2 caused by homozygous MME gene mutation]. Rinsho Shinkeigaku 2023; 63:743-747. [PMID: 37880116 DOI: 10.5692/clinicalneurol.cn-001870] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2023]
Abstract
The patient is a 44-year-old man. His parents are consanguineous. He experienced muscle weakness in his toe and distal tingling sensation in his feet at 42 years of age, which gradually progressed. Additionally, a marked cyanotic discoloration of the feet appeared and worsened progressively. Neurological examination revealed loss of tendon reflexes and distal muscle weakness in the lower extremities. Findings from nerve conduction studies indicated axonal polyneuropathy. Upon detection of the MME gene mutation, the patient was diagnosed with autosomal-recessive Charcot-Marie-Tooth disease 2T (ARCMT2T). In this case, cyanosis of the lower extremities possibly was associated with ARCMT2T, and it was suggested to be due to neprilysin deletion linked with the MME mutation. This represents the first documented occurrence of cyanosis as a distinctive feature of CMT with MME mutation.
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Affiliation(s)
- Masataka Yamashiro
- Department of Neurology, School of Medicine, University of Occupational and Environmental Health
| | - Keiko Ohnari
- Department of Neurology, School of Medicine, University of Occupational and Environmental Health
| | - Yujiro Higuchi
- Department of Neurology and Clinical Neuroscience, Kagoshima University Graduate School of Medical Science
| | - Hiroaki Hashiguchi
- Department of Neurology and Clinical Neuroscience, Kagoshima University Graduate School of Medical Science
| | - Hiroshi Takashima
- Department of Neurology and Clinical Neuroscience, Kagoshima University Graduate School of Medical Science
| | - Kazumasa Okada
- Department of Neurology, School of Medicine, University of Occupational and Environmental Health
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Waung MW, Ma F, Wheeler AG, Zai CC, So J. The Diagnostic Landscape of Adult Neurogenetic Disorders. BIOLOGY 2023; 12:1459. [PMID: 38132285 PMCID: PMC10740572 DOI: 10.3390/biology12121459] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/01/2023] [Revised: 11/11/2023] [Accepted: 11/16/2023] [Indexed: 12/23/2023]
Abstract
Neurogenetic diseases affect individuals across the lifespan, but accurate diagnosis remains elusive for many patients. Adults with neurogenetic disorders often undergo a long diagnostic odyssey, with multiple specialist evaluations and countless investigations without a satisfactory diagnostic outcome. Reasons for these diagnostic challenges include: (1) clinical features of neurogenetic syndromes are diverse and under-recognized, particularly those of adult-onset, (2) neurogenetic syndromes may manifest with symptoms that span multiple neurological and medical subspecialties, and (3) a positive family history may not be present or readily apparent. Furthermore, there is a large gap in the understanding of how to apply genetic diagnostic tools in adult patients, as most of the published literature focuses on the pediatric population. Despite these challenges, accurate genetic diagnosis is imperative to provide affected individuals and their families guidance on prognosis, recurrence risk, and, for an increasing number of disorders, offer targeted treatment. Here, we provide a framework for recognizing adult neurogenetic syndromes, describe the current diagnostic approach, and highlight studies using next-generation sequencing in different neurological disease cohorts. We also discuss diagnostic pitfalls, barriers to achieving a definitive diagnosis, and emerging technology that may increase the diagnostic yield of testing.
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Affiliation(s)
- Maggie W. Waung
- Division of General Neurology, Department of Neurology, Weill Institute for Neurosciences, University of California, San Francisco, CA 94158, USA
| | - Fion Ma
- Institute for Human Genetics, University of California San Francisco School of Medicine, San Francisco, CA 94143, USA
| | - Allison G. Wheeler
- Institute for Human Genetics, University of California San Francisco School of Medicine, San Francisco, CA 94143, USA
- Department of Neurology, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Clement C. Zai
- Tanenbaum Centre for Pharmacogenetics, Molecular Brain Science, Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, Toronto, ON M5T 1R8, Canada
- Department of Psychiatry, Institute of Medical Science, Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, ON M5S 1A8, Canada
| | - Joyce So
- Division of Medical Genetics, Department of Pediatrics, University of California, San Francisco, CA 94158, USA
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Asif M, Chiou CC, Hussain MF, Hussain M, Sajid Z, Gulsher M, Raheem A, Khan A, Nasreen N, Kloczkowski A, Hassan M, Iqbal F, Chen CC. Homozygous Mutations in GDAP1 and MFN2 Genes Resulted in Autosomal Recessive Forms of Charcot-Marie-Tooth Disease in Consanguineous Pakistani Families. DNA Cell Biol 2023; 42:697-708. [PMID: 37797217 DOI: 10.1089/dna.2023.0169] [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] [Indexed: 10/07/2023] Open
Abstract
Charcot-Marie-Tooth disease (CMT) is a heritable neurodegenerative disease of peripheral nervous system diseases in which more than 100 genes and their mutations are associated. Two consanguineous families Dera Ghazi Khan (PAK-CMT1-DG KHAN) and Layyah (PAK-CMT2-LAYYAH) with multiple CMT-affected subjects were enrolled from Punjab province in Pakistan. Basic epidemiological data were collected for the subjects. Nerve conduction study (NCS) and electromyography (EMG) were performed for the patients. Whole-exome sequencing (WES) followed by Sanger sequencing was applied to report the genetic basic of CMT. The NCS findings revealed that sensory and motor nerve conduction velocities for both families were <38 m/s. EMG presented denervation, neuropathic motor unit potential, and reduced interference pattern of peripheral nerves. WES identified that a novel nonsense mutation (c. 226 G>T) in GADP1 gene and a previously known missense mutation in MFN2 gene (c. 334 G>A) cause CMT4A (Charcot-Marie-Tooth disease type 4A) in the PAK-CMT1-DG KHAN family and CMT2A (Charcot-Marie-Tooth disease type 2A) in the PAK-CMT2-LAYYAH family, respectively. Mutations followed Mendelian pattern with autosomal recessive mode of inheritance. Multiple sequence alignment by Clustal Omega indicated that mutation-containing domain in both genes is highly conserved, and in situ analysis revealed that both mutations are likely to be pathogenic. We reported that a novel nonsense mutation and a previously known missense mutation in GAPD1 gene and MFN2 gene, respectively, cause CMT in consanguineous Pakistani families.
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Affiliation(s)
- Muhammad Asif
- Institute of Molecular Biology and Biotechnology. Bahauddin Zakariya University, Multan, Pakistan
- Institute of Zoology, Bahauddin Zakariya University, Multan, Pakistan
| | - Chien-Chun Chiou
- Department of Dermatology, Ditmanson Medical Foundation Chia-Yi Christian Hospital, Chiayi, Taiwan
| | | | - Manzoor Hussain
- Orthopedic Unit 1, Nishter Medical University Multan, Pakistan
| | - Zureesha Sajid
- Institute of Molecular Biology and Biotechnology. Bahauddin Zakariya University, Multan, Pakistan
- Department of Biotechnology, Institute of Biochemistry, Biotechnology and Bioinformatics, Baghdad-ul-Jadeed Campus, The Islamia University of Bahawalpur, Bahawalpur, Pakistan
| | - Muhammad Gulsher
- Children Hospital and Institute of Child Health, Multan, Pakistan
| | - Afifa Raheem
- Institute of Zoology, Bahauddin Zakariya University, Multan, Pakistan
| | - Adil Khan
- Department of Botany and Zoology, Bacha Khan University, Charsadda, Pakistan
| | - Nasreen Nasreen
- Department of Zoology, Abdul Wali Khan University, Mardan, Pakistan
| | - Andrzej Kloczkowski
- The Steve and Cindy Rasmussen Institute for Genomic Medicine, Nationwide Children's Hospital, Columbus, Ohio, USA
- Department of Pediatrics, The Ohio State University, Columbus, Ohio, USA
| | - Mubashir Hassan
- The Steve and Cindy Rasmussen Institute for Genomic Medicine, Nationwide Children's Hospital, Columbus, Ohio, USA
| | - Furhan Iqbal
- Institute of Zoology, Bahauddin Zakariya University, Multan, Pakistan
| | - Chien-Chin Chen
- Department of Pathology, Ditmanson Medical Foundation Chia-Yi Christian Hospital, Chiayi, Taiwan
- Department of Cosmetic Science, Chia Nan University of Pharmacy and Science, Tainan, Taiwan
- Ph.D. Program in Translational Medicine, Rong Hsing Research Center for Translational Medicine, National Chung Hsing University, Taichung, Taiwan
- Department of Biotechnology and Bioindustry Sciences, College of Bioscience and Biotechnology, National Cheng Kung University, Tainan, Taiwan
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Martínez Barreiro M, Vázquez Alberdi L, De León L, Avellanal G, Duarte A, Anzibar Fialho M, Baranger J, Calero M, Rubido N, Tanter M, Negreira C, Brum J, Damián JP, Kun A. In Vivo Ultrafast Doppler Imaging Combined with Confocal Microscopy and Behavioral Approaches to Gain Insight into the Central Expression of Peripheral Neuropathy in Trembler-J Mice. BIOLOGY 2023; 12:1324. [PMID: 37887034 PMCID: PMC10604841 DOI: 10.3390/biology12101324] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/14/2023] [Revised: 08/17/2023] [Accepted: 08/21/2023] [Indexed: 10/28/2023]
Abstract
The main human hereditary peripheral neuropathy (Charcot-Marie-Tooth, CMT), manifests in progressive sensory and motor deficits. Mutations in the compact myelin protein gene pmp22 cause more than 50% of all CMTs. CMT1E is a subtype of CMT1 myelinopathy carrying micro-mutations in pmp22. The Trembler-J mice have a spontaneous mutation in pmp22 identical to that present in CMT1E human patients. PMP22 is mainly (but not exclusively) expressed in Schwann cells. Some studies have found the presence of pmp22 together with some anomalies in the CNS of CMT patients. Recently, we identified the presence of higher hippocampal pmp22 expression and elevated levels of anxious behavior in TrJ/+ compared to those observed in wt. In the present paper, we delve deeper into the central expression of the neuropathy modeled in Trembler-J analyzing in vivo the cerebrovascular component by Ultrafast Doppler, exploring the vascular structure by scanning laser confocal microscopy, and analyzing the behavioral profile by anxiety and motor difficulty tests. We have found that TrJ/+ hippocampi have increased blood flow and a higher vessel volume compared with the wild type. Together with this, we found an anxiety-like profile in TrJ/+ and the motor difficulties described earlier. We demonstrate that there are specific cerebrovascular hemodynamics associated with a vascular structure and anxious behavior associated with the TrJ/+ clinical phenotype, a model of the human CMT1E disease.
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Affiliation(s)
- Mariana Martínez Barreiro
- Laboratorio de Biología Celular del Sistema Nervioso Periférico, Departamento de Proteínas y Ácidos Nucleicos, Instituto de Investigaciones Biológicas Clemente Estable, Montevideo 11600, Uruguay; (M.M.B.); (L.V.A.); (A.D.)
| | - Lucia Vázquez Alberdi
- Laboratorio de Biología Celular del Sistema Nervioso Periférico, Departamento de Proteínas y Ácidos Nucleicos, Instituto de Investigaciones Biológicas Clemente Estable, Montevideo 11600, Uruguay; (M.M.B.); (L.V.A.); (A.D.)
- Laboratorio de Acústica Ultrasonora, Instituto de Física, Facultad de Ciencias, Universidad de la República, Montevideo 11400, Uruguay; (M.A.F.); (C.N.); (J.B.)
| | - Lucila De León
- Departamento de Biociencias Veterinarias, Facultad de Veterinaria, Universidad de la República, Montevideo 13000, Uruguay; (L.D.L.); (G.A.); (J.P.D.)
| | - Guadalupe Avellanal
- Departamento de Biociencias Veterinarias, Facultad de Veterinaria, Universidad de la República, Montevideo 13000, Uruguay; (L.D.L.); (G.A.); (J.P.D.)
| | - Andrea Duarte
- Laboratorio de Biología Celular del Sistema Nervioso Periférico, Departamento de Proteínas y Ácidos Nucleicos, Instituto de Investigaciones Biológicas Clemente Estable, Montevideo 11600, Uruguay; (M.M.B.); (L.V.A.); (A.D.)
| | - Maximiliano Anzibar Fialho
- Laboratorio de Acústica Ultrasonora, Instituto de Física, Facultad de Ciencias, Universidad de la República, Montevideo 11400, Uruguay; (M.A.F.); (C.N.); (J.B.)
- Física No Lineal, Instituto de Física de Facultad de Ciencias, Universidad de la República, Montevideo 11400, Uruguay;
| | - Jérôme Baranger
- Physics for Medicine Paris, Inserm U1273, ESPCI Paris, PSL University, CNRS UMR 8063, 75012 Paris, France; (J.B.); (M.T.)
| | - Miguel Calero
- Unidad de Encefalopatías Espongiformes, UFIEC, CIBERNED, Instituto de Salud Carlos III, 28029 Madrid, Spain;
- Queen Sofia Foundation—Alzheimer Center, CIEN Foundation, 28031 Madrid, Spain
| | - Nicolás Rubido
- Física No Lineal, Instituto de Física de Facultad de Ciencias, Universidad de la República, Montevideo 11400, Uruguay;
- Institute for Complex Systems and Mathematical Biology, University of Aberdeen, King’s College, Aberdeen AB24 3UE, UK
| | - Mickael Tanter
- Physics for Medicine Paris, Inserm U1273, ESPCI Paris, PSL University, CNRS UMR 8063, 75012 Paris, France; (J.B.); (M.T.)
| | - Carlos Negreira
- Laboratorio de Acústica Ultrasonora, Instituto de Física, Facultad de Ciencias, Universidad de la República, Montevideo 11400, Uruguay; (M.A.F.); (C.N.); (J.B.)
| | - Javier Brum
- Laboratorio de Acústica Ultrasonora, Instituto de Física, Facultad de Ciencias, Universidad de la República, Montevideo 11400, Uruguay; (M.A.F.); (C.N.); (J.B.)
| | - Juan Pablo Damián
- Departamento de Biociencias Veterinarias, Facultad de Veterinaria, Universidad de la República, Montevideo 13000, Uruguay; (L.D.L.); (G.A.); (J.P.D.)
| | - Alejandra Kun
- Laboratorio de Biología Celular del Sistema Nervioso Periférico, Departamento de Proteínas y Ácidos Nucleicos, Instituto de Investigaciones Biológicas Clemente Estable, Montevideo 11600, Uruguay; (M.M.B.); (L.V.A.); (A.D.)
- Sección Bioquímica, Facultad de Ciencias, Universidad de la República, Montevideo 11400, Uruguay
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Ando M, Higuchi Y, Yuan JH, Yoshimura A, Dozono M, Hobara T, Kojima F, Noguchi Y, Takeuchi M, Takei J, Hiramatsu Y, Nozuma S, Nakamura T, Sakiyama Y, Hashiguchi A, Matsuura E, Okamoto Y, Sone J, Takashima H. Clinical phenotypic diversity of NOTCH2NLC-related disease in the largest case series of inherited peripheral neuropathy in Japan. J Neurol Neurosurg Psychiatry 2023; 94:622-630. [PMID: 36948577 DOI: 10.1136/jnnp-2022-330769] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/15/2022] [Accepted: 03/07/2023] [Indexed: 03/24/2023]
Abstract
BACKGROUND NOTCH2NLC GGC repeat expansions have been associated with various neurogenerative disorders, including neuronal intranuclear inclusion disease and inherited peripheral neuropathies (IPNs). However, only a few NOTCH2NLC-related disease studies in IPN have been reported, and the clinical and genetic spectra remain unclear. Thus, this study aimed to describe the clinical and genetic manifestations of NOTCH2NLC-related IPNs. METHOD Among 2692 Japanese patients clinically diagnosed with IPN/Charcot-Marie-Tooth disease (CMT), we analysed NOTCH2NLC repeat expansion in 1783 unrelated patients without a genetic diagnosis. Screening and repeat size determination of NOTCH2NLC repeat expansion were performed using repeat-primed PCR and fluorescence amplicon length analysis-PCR. RESULTS NOTCH2NLC repeat expansions were identified in 26 cases of IPN/CMT from 22 unrelated families. The mean median motor nerve conduction velocity was 41 m/s (range, 30.8-59.4), and 18 cases (69%) were classified as intermediate CMT. The mean age of onset was 32.7 (range, 7-61) years. In addition to motor sensory neuropathy symptoms, dysautonomia and involuntary movements were common (44% and 29%). Furthermore, the correlation between the age of onset or clinical symptoms and the repeat size remains unclear. CONCLUSIONS These findings of this study help us understand the clinical heterogeneity of NOTCH2NLC-related disease, such as non-length-dependent motor dominant phenotype and prominent autonomic involvement. This study also emphasise the importance of genetic screening, regardless of the age of onset and type of CMT, particularly in patients of Asian origin, presenting with intermediate conduction velocities and dysautonomia.
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Affiliation(s)
- Masahiro Ando
- Department of Neurology and Geriatrics, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima, Japan
| | - Yujiro Higuchi
- Department of Neurology and Geriatrics, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima, Japan
| | - Jun-Hui Yuan
- Department of Neurology and Geriatrics, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima, Japan
| | - Akiko Yoshimura
- Department of Neurology and Geriatrics, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima, Japan
| | - Mika Dozono
- Department of Neurology and Geriatrics, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima, Japan
| | - Takahiro Hobara
- Department of Neurology and Geriatrics, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima, Japan
| | - Fumikazu Kojima
- Department of Neurology and Geriatrics, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima, Japan
| | - Yutaka Noguchi
- Department of Neurology and Geriatrics, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima, Japan
| | - Mika Takeuchi
- Department of Neurology and Geriatrics, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima, Japan
| | - Jun Takei
- Department of Neurology and Geriatrics, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima, Japan
| | - Yu Hiramatsu
- Department of Neurology and Geriatrics, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima, Japan
| | - Satoshi Nozuma
- Department of Neurology and Geriatrics, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima, Japan
| | - Tomonori Nakamura
- Department of Neurology and Geriatrics, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima, Japan
| | - Yusuke Sakiyama
- Department of Neurology and Geriatrics, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima, Japan
| | - Akihiro Hashiguchi
- Department of Neurology and Geriatrics, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima, Japan
| | - Eiji Matsuura
- Department of Neurology and Geriatrics, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima, Japan
| | - Yuji Okamoto
- Department of Neurology and Geriatrics, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima, Japan
- Department of Physical Therapy, Kagoshima University of School of Health Sciences, Kagoshima, Japan
| | - Jun Sone
- Department of Neuropathology, Aichi Medical University, Aichi, Japan
| | - Hiroshi Takashima
- Department of Neurology and Geriatrics, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima, Japan
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Okamoto Y, Takashima H. The Current State of Charcot-Marie-Tooth Disease Treatment. Genes (Basel) 2023; 14:1391. [PMID: 37510296 PMCID: PMC10379063 DOI: 10.3390/genes14071391] [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: 05/28/2023] [Revised: 06/20/2023] [Accepted: 06/29/2023] [Indexed: 07/30/2023] Open
Abstract
Charcot-Marie-Tooth disease (CMT) and associated neuropathies are the most predominant genetically transmitted neuromuscular conditions; however, effective pharmacological treatments have not established. The extensive genetic heterogeneity of CMT, which impacts the peripheral nerves and causes lifelong disability, presents a significant barrier to the development of comprehensive treatments. An estimated 100 loci within the human genome are linked to various forms of CMT and its related inherited neuropathies. This review delves into prospective therapeutic strategies used for the most frequently encountered CMT variants, namely CMT1A, CMT1B, CMTX1, and CMT2A. Compounds such as PXT3003, which are being clinically and preclinically investigated, and a broad array of therapeutic agents and their corresponding mechanisms are discussed. Furthermore, the progress in established gene therapy techniques, including gene replacement via viral vectors, exon skipping using antisense oligonucleotides, splicing modification, and gene knockdown, are appraised. Each of these gene therapies has the potential for substantial advancements in future research.
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Affiliation(s)
- Yuji Okamoto
- Department of Neurology and Geriatrics, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima 890-8544, Japan
- Department of Physical Therapy, School of Health Sciences, Faculty of Medicine, Kagoshima University, Kagoshima 890-8544, Japan
| | - Hiroshi Takashima
- Department of Neurology and Geriatrics, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima 890-8544, Japan
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Hirsch Y, Chung WK, Novoselov S, Weimer LH, Rossor A, LeDuc CA, McPartland AJ, Cabrera E, Ekstein J, Scher S, Nelson RF, Schiavo G, Henderson LB, Booth KTA. Biallelic Loss-of-Function Variants in BICD1 Are Associated with Peripheral Neuropathy and Hearing Loss. Int J Mol Sci 2023; 24:8897. [PMID: 37240244 PMCID: PMC10219021 DOI: 10.3390/ijms24108897] [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: 03/27/2023] [Revised: 05/16/2023] [Accepted: 05/16/2023] [Indexed: 05/28/2023] Open
Abstract
Hearing loss and peripheral neuropathy are two clinical entities that are genetically and phenotypically heterogeneous and sometimes co-occurring. Using exome sequencing and targeted segregation analysis, we investigated the genetic etiology of peripheral neuropathy and hearing loss in a large Ashkenazi Jewish family. Moreover, we assessed the production of the candidate protein via western blotting of lysates from fibroblasts from an affected individual and an unaffected control. Pathogenic variants in known disease genes associated with hearing loss and peripheral neuropathy were excluded. A homozygous frameshift variant in the BICD1 gene, c.1683dup (p.(Arg562Thrfs*18)), was identified in the proband and segregated with hearing loss and peripheral neuropathy in the family. The BIDC1 RNA analysis from patient fibroblasts showed a modest reduction in gene transcripts compared to the controls. In contrast, protein could not be detected in fibroblasts from a homozygous c.1683dup individual, whereas BICD1 was detected in an unaffected individual. Our findings indicate that bi-allelic loss-of-function variants in BICD1 are associated with hearing loss and peripheral neuropathy. Definitive evidence that bi-allelic loss-of-function variants in BICD1 cause peripheral neuropathy and hearing loss will require the identification of other families and individuals with similar variants with the same phenotype.
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Affiliation(s)
- Yoel Hirsch
- Dor Yeshorim, Committee for Prevention Jewish Genetic Diseases, Brooklyn, NY 11211, USA
| | - Wendy K. Chung
- Departments of Pediatrics and Medicine, Columbia University Irving Medical Center, New York, NY 10032, USA
| | - Sergey Novoselov
- Department of Neuromuscular Diseases, UCL Queen Square Institute of Neurology, London WC1N 3BG, UK
| | - Louis H. Weimer
- Department of Neurology, Columbia University Irving Medical Center, New York, NY 10032, USA
| | - Alexander Rossor
- Department of Neuromuscular Diseases, UCL Queen Square Institute of Neurology, London WC1N 3BG, UK
| | - Charles A. LeDuc
- Departments of Pediatrics and Medicine, Columbia University Irving Medical Center, New York, NY 10032, USA
| | - Amanda J. McPartland
- Departments of Pediatrics and Medicine, Columbia University Irving Medical Center, New York, NY 10032, USA
| | - Ernesto Cabrera
- Department of Otolaryngology-Head and Neck Surgery, Indiana University School of Medicine, Indianapolis, IN 46202, USA
| | - Josef Ekstein
- Dor Yeshorim, Committee for Prevention Jewish Genetic Diseases, Brooklyn, NY 11211, USA
| | - Sholem Scher
- Dor Yeshorim, Committee for Prevention Jewish Genetic Diseases, Brooklyn, NY 11211, USA
| | - Rick F. Nelson
- Department of Otolaryngology-Head and Neck Surgery, Indiana University School of Medicine, Indianapolis, IN 46202, USA
| | - Giampietro Schiavo
- Department of Neuromuscular Diseases, UCL Queen Square Institute of Neurology, London WC1N 3BG, UK
- UK Dementia Research Institute at UCL, London WC1E 6BT, UK
| | | | - Kevin T. A. Booth
- Department of Otolaryngology-Head and Neck Surgery, Indiana University School of Medicine, Indianapolis, IN 46202, USA
- Medical and Molecular Medicine, Indiana University School of Medicine, Indianapolis, IN 46202, USA
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9
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Kang KH, Han JE, Kim H, Kim S, Hong YB, Yun J, Nam SH, Choi BO, Koh H. PINK1 and Parkin Ameliorate the Loss of Motor Activity and Mitochondrial Dysfunction Induced by Peripheral Neuropathy-Associated HSPB8 Mutants in Drosophila Models. Biomedicines 2023; 11:biomedicines11030832. [PMID: 36979812 PMCID: PMC10045361 DOI: 10.3390/biomedicines11030832] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2023] [Revised: 03/01/2023] [Accepted: 03/07/2023] [Indexed: 03/12/2023] Open
Abstract
Charcot–Marie–Tooth disease (CMT) is a group of inherited peripheral nerve disorders characterized by progressive muscle weakness and atrophy, sensory loss, foot deformities and steppage gait. Missense mutations in the gene encoding the small heat shock protein HSPB8 (HSP22) have been associated with hereditary neuropathies, including CMT. HSPB8 is a member of the small heat shock protein family sharing a highly conserved α-crystallin domain that is critical to its chaperone activity. In this study, we modeled HSPB8 mutant-induced neuropathies in Drosophila. The overexpression of human HSPB8 mutants in Drosophila neurons produced no significant defect in fly development but led to a partial reduction in fly lifespan. Although these HSPB8 mutant genes failed to induce sensory abnormalities, they reduced the motor activity of flies and the mitochondrial functions in fly neuronal tissue. The motor defects and mitochondrial dysfunction were successfully restored by PINK1 and parkin, which are Parkinson’s disease-associated genes that have critical roles in maintaining mitochondrial function and integrity. Consistently, kinetin riboside, a small molecule amplifying PINK1 activity, also rescued the loss of motor activity in our HSPB8 mutant model.
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Affiliation(s)
- Kyong-hwa Kang
- Department of Pharmacology, Dong-A University College of Medicine, Busan 49201, Republic of Korea
- Neuroscience Translational Research Solution Center, Dong-A University College of Medicine, Busan 49201, Republic of Korea
| | - Ji Eun Han
- Department of Pharmacology, Dong-A University College of Medicine, Busan 49201, Republic of Korea
- Department of Translational Biomedical Sciences, Dong-A University College of Medicine, Busan 49201, Republic of Korea
| | - Hyunjin Kim
- Department of Pharmacology, Dong-A University College of Medicine, Busan 49201, Republic of Korea
- Neuroscience Translational Research Solution Center, Dong-A University College of Medicine, Busan 49201, Republic of Korea
| | - Sohee Kim
- Department of Pharmacology, Dong-A University College of Medicine, Busan 49201, Republic of Korea
- Department of Translational Biomedical Sciences, Dong-A University College of Medicine, Busan 49201, Republic of Korea
| | - Young Bin Hong
- Neuroscience Translational Research Solution Center, Dong-A University College of Medicine, Busan 49201, Republic of Korea
- Department of Translational Biomedical Sciences, Dong-A University College of Medicine, Busan 49201, Republic of Korea
- Peripheral Neuropathy Research Center, Dong-A University College of Medicine, Busan 49201, Republic of Korea
- Department of Biochemistry, Dong-A University College of Medicine, Busan 49201, Republic of Korea
| | - Jeanho Yun
- Neuroscience Translational Research Solution Center, Dong-A University College of Medicine, Busan 49201, Republic of Korea
- Department of Translational Biomedical Sciences, Dong-A University College of Medicine, Busan 49201, Republic of Korea
- Peripheral Neuropathy Research Center, Dong-A University College of Medicine, Busan 49201, Republic of Korea
- Department of Biochemistry, Dong-A University College of Medicine, Busan 49201, Republic of Korea
| | - Soo Hyun Nam
- Peripheral Neuropathy Research Center, Dong-A University College of Medicine, Busan 49201, Republic of Korea
- Department of Neurology, Sungkyunkwan University School of Medicine, Seoul 06351, Republic of Korea
| | - Byung-Ok Choi
- Department of Neurology, Sungkyunkwan University School of Medicine, Seoul 06351, Republic of Korea
| | - Hyongjong Koh
- Department of Pharmacology, Dong-A University College of Medicine, Busan 49201, Republic of Korea
- Neuroscience Translational Research Solution Center, Dong-A University College of Medicine, Busan 49201, Republic of Korea
- Department of Translational Biomedical Sciences, Dong-A University College of Medicine, Busan 49201, Republic of Korea
- Peripheral Neuropathy Research Center, Dong-A University College of Medicine, Busan 49201, Republic of Korea
- Correspondence: ; Tel.: +82-51-240-2805
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10
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Maria Turco E, Maria Giada Giovenale A, Rotundo G, Mazzoni M, Zanfardino P, Frezza K, Torrente I, Mary Carletti R, Damiani D, Santorelli FM, Luigi Vescovi A, Petruzzella V, Rosati J. Generation and characterization of CSSi016-A (9938) human pluripotent stem cell line carrying two biallelic variants in MTMR5/SBF1 gene resulting in a case of severe CMT4B3. Stem Cell Res 2022; 65:102946. [PMID: 36272304 DOI: 10.1016/j.scr.2022.102946] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/07/2022] [Revised: 10/12/2022] [Accepted: 10/16/2022] [Indexed: 11/19/2022] Open
Abstract
Charcot-Marie-Tooth type 4B3 (CMT4B3) is a rare subtype of hereditary neuropathy associated with variants in the MTMR5/SBF1 gene. Herein, we report the generation and characterization of a hiPSC line from a 12-year-old Italian girl with early onset severe polyneuropathy with motor and axonal involvement, harboring biallelic variants in the MTMR5/SBF1 gene. Fibroblasts were reprogrammed using non-integrating episomal plasmids, and iPSCs successfully passed the stemness and pluripotency tests. Patient-specific hiPSCs were produced to obtain a disease model for the study of this rare condition.
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Affiliation(s)
- Elisa Maria Turco
- Cellular Reprogramming Unit, Fondazione IRCCS Casa Sollievo della Sofferenza, Viale dei Cappuccini, 71013 San Giovanni Rotondo (FG), Italy
| | - Angela Maria Giada Giovenale
- Cellular Reprogramming Unit, Fondazione IRCCS Casa Sollievo della Sofferenza, Viale dei Cappuccini, 71013 San Giovanni Rotondo (FG), Italy; Department of Biotechnology and Biosciences, University of Milano-Bicocca, P.zza della Scienza,2, 20126 Milan, Italy
| | - Giovannina Rotundo
- Cellular Reprogramming Unit, Fondazione IRCCS Casa Sollievo della Sofferenza, Viale dei Cappuccini, 71013 San Giovanni Rotondo (FG), Italy
| | - Martina Mazzoni
- Cellular Reprogramming Unit, Fondazione IRCCS Casa Sollievo della Sofferenza, Viale dei Cappuccini, 71013 San Giovanni Rotondo (FG), Italy
| | - Paola Zanfardino
- Department of Translational Biomedicine and Neurosciences, University of Bari Aldo Moro, Piazza G. Cesare, 11, 70124 Bari, Italy
| | - Katia Frezza
- Medical Genetics Unit, Fondazione IRCCS Casa Sollievo della Sofferenza, Viale dei Cappuccini, 71013 San Giovanni Rotondo, Italy
| | - Isabella Torrente
- Medical Genetics Unit, Fondazione IRCCS Casa Sollievo della Sofferenza, Viale dei Cappuccini, 71013 San Giovanni Rotondo, Italy
| | - Rose Mary Carletti
- Cellular Reprogramming Unit, Fondazione IRCCS Casa Sollievo della Sofferenza, Viale dei Cappuccini, 71013 San Giovanni Rotondo (FG), Italy
| | | | | | - Angelo Luigi Vescovi
- Cellular Reprogramming Unit, Fondazione IRCCS Casa Sollievo della Sofferenza, Viale dei Cappuccini, 71013 San Giovanni Rotondo (FG), Italy; Department of Biotechnology and Biosciences, University of Milano-Bicocca, P.zza della Scienza,2, 20126 Milan, Italy
| | - Vittoria Petruzzella
- Department of Translational Biomedicine and Neurosciences, University of Bari Aldo Moro, Piazza G. Cesare, 11, 70124 Bari, Italy.
| | - Jessica Rosati
- Cellular Reprogramming Unit, Fondazione IRCCS Casa Sollievo della Sofferenza, Viale dei Cappuccini, 71013 San Giovanni Rotondo (FG), Italy.
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11
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Neurons: The Interplay between Cytoskeleton, Ion Channels/Transporters and Mitochondria. Cells 2022; 11:cells11162499. [PMID: 36010576 PMCID: PMC9406945 DOI: 10.3390/cells11162499] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2022] [Revised: 08/06/2022] [Accepted: 08/09/2022] [Indexed: 11/17/2022] Open
Abstract
Neurons are permanent cells whose key feature is information transmission via chemical and electrical signals. Therefore, a finely tuned homeostasis is necessary to maintain function and preserve neuronal lifelong survival. The cytoskeleton, and in particular microtubules, are far from being inert actors in the maintenance of this complex cellular equilibrium, and they participate in the mobilization of molecular cargos and organelles, thus influencing neuronal migration, neuritis growth and synaptic transmission. Notably, alterations of cytoskeletal dynamics have been linked to alterations of neuronal excitability. In this review, we discuss the characteristics of the neuronal cytoskeleton and provide insights into alterations of this component leading to human diseases, addressing how these might affect excitability/synaptic activity, as well as neuronal functioning. We also provide an overview of the microscopic approaches to visualize and assess the cytoskeleton, with a specific focus on mitochondrial trafficking.
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12
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Jung NY, Kwon HM, Nam DE, Tamanna N, Lee AJ, Kim SB, Choi BO, Chung KW. Peripheral Myelin Protein 22 Gene Mutations in Charcot-Marie-Tooth Disease Type 1E Patients. Genes (Basel) 2022; 13:genes13071219. [PMID: 35886002 PMCID: PMC9321036 DOI: 10.3390/genes13071219] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2022] [Revised: 06/27/2022] [Accepted: 07/04/2022] [Indexed: 02/04/2023] Open
Abstract
Duplication and deletion of the peripheral myelin protein 22 (PMP22) gene cause Charcot-Marie-Tooth disease type 1A (CMT1A) and hereditary neuropathy with liability to pressure palsies (HNPP), respectively, while point mutations or small insertions and deletions (indels) usually cause CMT type 1E (CMT1E) or HNPP. This study was performed to identify PMP22 mutations and to analyze the genotype−phenotype correlation in Korean CMT families. By the application of whole-exome sequencing (WES) and targeted gene panel sequencing (TS), we identified 14 pathogenic or likely pathogenic PMP22 mutations in 21 families out of 850 CMT families who were negative for 17p12 (PMP22) duplication. Most mutations were located in the well-conserved transmembrane domains. Of these, eight mutations were not reported in other populations. High frequencies of de novo mutations were observed, and the mutation sites of c.68C>G and c.215C>T were suggested as the mutational hotspots. Affected individuals showed an early onset-severe phenotype and late onset-mild phenotype, and more than 40% of the CMT1E patients showed hearing loss. Physical and electrophysiological symptoms of the CMT1E patients were more severely damaged than those of CMT1A while similar to CMT1B caused by MPZ mutations. Our results will be useful for the reference data of Korean CMT1E and the molecular diagnosis of CMT1 with or without hearing loss.
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Affiliation(s)
- Na Young Jung
- Department of Biological Sciences, Kongju National University, Gongju 32588, Korea; (N.Y.J.); (D.E.N.); (N.T.); (A.J.L.)
| | - Hye Mi Kwon
- Department of Neurology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul 06351, Korea;
| | - Da Eun Nam
- Department of Biological Sciences, Kongju National University, Gongju 32588, Korea; (N.Y.J.); (D.E.N.); (N.T.); (A.J.L.)
| | - Nasrin Tamanna
- Department of Biological Sciences, Kongju National University, Gongju 32588, Korea; (N.Y.J.); (D.E.N.); (N.T.); (A.J.L.)
| | - Ah Jin Lee
- Department of Biological Sciences, Kongju National University, Gongju 32588, Korea; (N.Y.J.); (D.E.N.); (N.T.); (A.J.L.)
| | - Sang Beom Kim
- Department of Neurology, Kyung Hee University Hospital at Gangdong, Kyung Hee University School of Medicine, Seoul 05278, Korea;
| | - Byung-Ok Choi
- Department of Neurology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul 06351, Korea;
- Cell & Gene Therapy Institute, Samsung Medical Center, Seoul 06351, Korea
- Correspondence: (B.-O.C.); (K.W.C.); Tel.: +82-2-3410-1296 (B.-O.C.); +82-41-850-8506 (K.W.C.)
| | - Ki Wha Chung
- Department of Biological Sciences, Kongju National University, Gongju 32588, Korea; (N.Y.J.); (D.E.N.); (N.T.); (A.J.L.)
- Correspondence: (B.-O.C.); (K.W.C.); Tel.: +82-2-3410-1296 (B.-O.C.); +82-41-850-8506 (K.W.C.)
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13
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Ando M, Higuchi Y, Yuan J, Yoshimura A, Taniguchi T, Kojima F, Noguchi Y, Hobara T, Takeuchi M, Takei J, Hiramatsu Y, Sakiyama Y, Hashiguchi A, Okamoto Y, Mitsui J, Ishiura H, Tsuji S, Takashima H. Comprehensive Genetic Analyses of Inherited Peripheral Neuropathies in Japan: Making Early Diagnosis Possible. Biomedicines 2022; 10:biomedicines10071546. [PMID: 35884855 PMCID: PMC9312503 DOI: 10.3390/biomedicines10071546] [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: 06/07/2022] [Revised: 06/23/2022] [Accepted: 06/25/2022] [Indexed: 11/18/2022] Open
Abstract
Various genomic variants were linked to inherited peripheral neuropathies (IPNs), including large duplication/deletion and repeat expansion, making genetic diagnosis challenging. This large case series aimed to identify the genetic characteristics of Japanese patients with IPNs. We collected data on 2695 IPN cases throughout Japan, in which PMP22 copy number variation (CNV) was pre-excluded. Genetic analyses were performed using DNA microarrays, next-generation sequencing-based gene panel sequencing, whole-exome sequencing, CNV analysis, and RFC1 repeat expansion analysis. The overall diagnostic rate and the genetic spectrum of patients were summarized. We identified 909 cases with suspected IPNs, pathogenic or likely pathogenic variants. The most common causative genes were MFN2, GJB1, MPZ, and MME. MFN2 was the most common cause for early-onset patients, whereas GJB1 and MPZ were the leading causes of middle-onset and late-onset patients, respectively. Meanwhile, GJB1 and MFN2 were leading causes for demyelinating and axonal subtypes, respectively. Additionally, we identified CNVs in MPZ and GJB1 genes and RFC1 repeat expansions. Comprehensive genetic analyses explicitly demonstrated the genetic basis of our IPN case series. A further understanding of the clinical characteristics of IPN and genetic spectrum would assist in developing efficient genetic testing strategies and facilitate early diagnosis.
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Affiliation(s)
- Masahiro Ando
- Department of Neurology and Geriatrics, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima 890-8520, Japan; (M.A.); (Y.H.); (J.Y.); (A.Y.); (T.T.); (F.K.); (Y.N.); (T.H.); (M.T.); (J.T.); (Y.H.); (Y.S.); (A.H.); (Y.O.)
| | - Yujiro Higuchi
- Department of Neurology and Geriatrics, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima 890-8520, Japan; (M.A.); (Y.H.); (J.Y.); (A.Y.); (T.T.); (F.K.); (Y.N.); (T.H.); (M.T.); (J.T.); (Y.H.); (Y.S.); (A.H.); (Y.O.)
| | - Junhui Yuan
- Department of Neurology and Geriatrics, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima 890-8520, Japan; (M.A.); (Y.H.); (J.Y.); (A.Y.); (T.T.); (F.K.); (Y.N.); (T.H.); (M.T.); (J.T.); (Y.H.); (Y.S.); (A.H.); (Y.O.)
| | - Akiko Yoshimura
- Department of Neurology and Geriatrics, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima 890-8520, Japan; (M.A.); (Y.H.); (J.Y.); (A.Y.); (T.T.); (F.K.); (Y.N.); (T.H.); (M.T.); (J.T.); (Y.H.); (Y.S.); (A.H.); (Y.O.)
| | - Takaki Taniguchi
- Department of Neurology and Geriatrics, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima 890-8520, Japan; (M.A.); (Y.H.); (J.Y.); (A.Y.); (T.T.); (F.K.); (Y.N.); (T.H.); (M.T.); (J.T.); (Y.H.); (Y.S.); (A.H.); (Y.O.)
| | - Fumikazu Kojima
- Department of Neurology and Geriatrics, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima 890-8520, Japan; (M.A.); (Y.H.); (J.Y.); (A.Y.); (T.T.); (F.K.); (Y.N.); (T.H.); (M.T.); (J.T.); (Y.H.); (Y.S.); (A.H.); (Y.O.)
| | - Yutaka Noguchi
- Department of Neurology and Geriatrics, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima 890-8520, Japan; (M.A.); (Y.H.); (J.Y.); (A.Y.); (T.T.); (F.K.); (Y.N.); (T.H.); (M.T.); (J.T.); (Y.H.); (Y.S.); (A.H.); (Y.O.)
| | - Takahiro Hobara
- Department of Neurology and Geriatrics, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima 890-8520, Japan; (M.A.); (Y.H.); (J.Y.); (A.Y.); (T.T.); (F.K.); (Y.N.); (T.H.); (M.T.); (J.T.); (Y.H.); (Y.S.); (A.H.); (Y.O.)
| | - Mika Takeuchi
- Department of Neurology and Geriatrics, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima 890-8520, Japan; (M.A.); (Y.H.); (J.Y.); (A.Y.); (T.T.); (F.K.); (Y.N.); (T.H.); (M.T.); (J.T.); (Y.H.); (Y.S.); (A.H.); (Y.O.)
| | - Jun Takei
- Department of Neurology and Geriatrics, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima 890-8520, Japan; (M.A.); (Y.H.); (J.Y.); (A.Y.); (T.T.); (F.K.); (Y.N.); (T.H.); (M.T.); (J.T.); (Y.H.); (Y.S.); (A.H.); (Y.O.)
| | - Yu Hiramatsu
- Department of Neurology and Geriatrics, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima 890-8520, Japan; (M.A.); (Y.H.); (J.Y.); (A.Y.); (T.T.); (F.K.); (Y.N.); (T.H.); (M.T.); (J.T.); (Y.H.); (Y.S.); (A.H.); (Y.O.)
| | - Yusuke Sakiyama
- Department of Neurology and Geriatrics, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima 890-8520, Japan; (M.A.); (Y.H.); (J.Y.); (A.Y.); (T.T.); (F.K.); (Y.N.); (T.H.); (M.T.); (J.T.); (Y.H.); (Y.S.); (A.H.); (Y.O.)
| | - Akihiro Hashiguchi
- Department of Neurology and Geriatrics, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima 890-8520, Japan; (M.A.); (Y.H.); (J.Y.); (A.Y.); (T.T.); (F.K.); (Y.N.); (T.H.); (M.T.); (J.T.); (Y.H.); (Y.S.); (A.H.); (Y.O.)
| | - Yuji Okamoto
- Department of Neurology and Geriatrics, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima 890-8520, Japan; (M.A.); (Y.H.); (J.Y.); (A.Y.); (T.T.); (F.K.); (Y.N.); (T.H.); (M.T.); (J.T.); (Y.H.); (Y.S.); (A.H.); (Y.O.)
- Department of Physical Therapy, School of Health Sciences, Faculty of Medicine, Kagoshima University, Kagoshima 890-8520, Japan
| | - Jun Mitsui
- Department of Neurology, Graduate School of Medicine, The University of Tokyo, Tokyo 113-8655, Japan; (J.M.); (H.I.); (S.T.)
| | - Hiroyuki Ishiura
- Department of Neurology, Graduate School of Medicine, The University of Tokyo, Tokyo 113-8655, Japan; (J.M.); (H.I.); (S.T.)
| | - Shoji Tsuji
- Department of Neurology, Graduate School of Medicine, The University of Tokyo, Tokyo 113-8655, Japan; (J.M.); (H.I.); (S.T.)
- Institute of Medical Genomics, International University of Health and Welfare, Chiba 107-8402, Japan
| | - Hiroshi Takashima
- Department of Neurology and Geriatrics, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima 890-8520, Japan; (M.A.); (Y.H.); (J.Y.); (A.Y.); (T.T.); (F.K.); (Y.N.); (T.H.); (M.T.); (J.T.); (Y.H.); (Y.S.); (A.H.); (Y.O.)
- Correspondence: ; Tel.: +81-99-275-5332
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