51
|
Abstract
PURPOSE OF REVIEW Charcot-Marie-Tooth disease (CMT) and related neuropathies represent a heterogeneous group of hereditary disorders. The present review will discuss the most recent advances in the field. RECENT FINDINGS Knowledge of CMT epidemiology and frequency of the main associated genes is increasing, with an overall prevalence estimated at 10-28/100 000. In the last years, the huge number of newly uncovered genes, thanks to next-generation sequencing techniques, is challenging the current classification of CMT. During the last 18 months other genes have been associated with CMT, such as PMP2, MORC2, NEFH, MME, and DGAT2. For the most common forms of CMT, numerous promising compounds are under study in cellular and animal models, mainly targeting either the protein degradation pathway or the protein overexpression. Consequently, efforts are devoted to develop responsive outcome measures and biomarkers for this overall slowly progressive disorder, with quantitative muscle MRI resulting the most sensitive-to-change measure. SUMMARY This is a rapidly evolving field where better understanding of pathophysiology is paving the way to develop potentially effective treatments, part of which will soon be tested in patients. Intense research is currently devoted to prepare clinical trials and develop responsive outcome measures.
Collapse
|
52
|
Masingue M, Perrot J, Carlier RY, Piguet-Lacroix G, Latour P, Stojkovic T. WES homozygosity mapping in a recessive form of Charcot-Marie-Tooth neuropathy reveals intronic GDAP1 variant leading to a premature stop codon. Neurogenetics 2018; 19:67-76. [PMID: 29396836 DOI: 10.1007/s10048-018-0539-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2017] [Revised: 01/19/2018] [Accepted: 01/23/2018] [Indexed: 01/06/2023]
Abstract
Charcot-Marie-Tooth disease (CMT) refers to a group of clinically and genetically heterogeneous inherited neuropathies. Ganglioside-induced differentiation-associated protein 1 GDAP1-related CMT has been reported in an autosomal dominant or recessive form in patients presenting either axonal or demyelinating neuropathy. We report two Sri Lankan sisters born to consanguineous parents and presenting with a severe axonal sensorimotor neuropathy. The early onset of the disease, the distal and proximal weakness and atrophy leading to major disability, along with areflexia, and, most notably, vocal cord and diaphragm paralysis were highly evocative of a GDAP1-related CMT. However, sequencing of the coding regions of the gene was normal. Whole-exome sequencing (WES) was performed and revealed that the largest region of homozygosity was around GDAP1 with several variants, mostly in non-coding regions. In view of the high clinical suspicion of GDAP1 gene involvement, we examined the variants in this gene and this, along with functional studies, allowed us to identify an alternative splicing site revealing a cryptic in-frame stop codon in intron 4 responsible for a severe loss of wild-type GDAP1. This work is the first to describe a deleterious mutation in GDAP1 gene outside of coding sequences or intronic junctions and emphasizes the importance of interpreting molecular analysis, and in particular WES results, in light of the clinical and electrophysiological phenotype.
Collapse
Affiliation(s)
- Marion Masingue
- Centre de Référence de pathologie neuromusculaire Paris-Est, Institut de Myologie, GHU Pitié-Salpêtrière, Paris, France.
| | - Jimmy Perrot
- Department of Neurobiology, Centre de Biologie Est, Hospices Civils de Lyon, Lyon, France
| | - Robert-Yves Carlier
- Department of Medical Imaging, Hôpitaux universitaires Paris Ile-de-France Ouest, Hôpital Raymond Poincaré, Garches, France
| | | | - Philippe Latour
- Department of Neurobiology, Centre de Biologie Est, Hospices Civils de Lyon, Lyon, France
| | - Tanya Stojkovic
- Centre de Référence de pathologie neuromusculaire Paris-Est, Institut de Myologie, GHU Pitié-Salpêtrière, Paris, France
| |
Collapse
|
53
|
Hirano M, Oka N, Hashiguchi A, Ueno S, Sakamoto H, Takashima H, Higuchi Y, Kusunoki S, Nakamura Y. Histopathological features of a patient with Charcot-Marie-Tooth disease type 2U/AD-CMTax-MARS. J Peripher Nerv Syst 2018; 21:370-374. [PMID: 27717217 DOI: 10.1111/jns.12193] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2016] [Revised: 10/01/2016] [Accepted: 10/04/2016] [Indexed: 12/25/2022]
Abstract
Charcot-Marie-Tooth (CMT) disease is a complex of peripheral nervous system disorders. CMT type 2U (CMT2U) is an autosomal dominant (AD) disease caused by mutations in the MARS gene encoding methionyl-tRNA synthetase; this disease has thus been newly called AD-CMTax-MARS. A few families with mutations in the MARS gene have been reported, without detailed histopathological findings. We describe a 70-year-old woman who had bilateral dysesthesia of the soles since the age of 66 years. Sural nerve biopsy showed a decrease in the density of large myelinated nerve fibers. Increased clusters of regenerating myelinated nerve fibers were noted. Electron microscopic analyses revealed degeneration of unmyelinated nerves. There was no vasculitis or inflammatory cell infiltration. Genetic analysis identified a heterozygous p.P800T mutation, a reported mutation in the MARS gene. We report the detailed histopathological findings in a patient with CMT2U/AD-CMTax-MARS. The findings are similar to those found in CMT2D caused by mutations in the GARS gene, encoding glycyl-tRNA synthetase.
Collapse
Affiliation(s)
- Makito Hirano
- Department of Neurology, Sakai Hospital Kindai University Faculty of Medicine, Sakai, Japan.,Department of Neurology, Kindai University Faculty of Medicine, Osakasayama, Japan
| | - Nobuyuki Oka
- Department of Neurology, National Hospital Organization Minami-Kyoto Hospital, Joyo, Japan
| | - Akihiro Hashiguchi
- Department of Neurology and Geriatrics, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima, Japan
| | - Shuichi Ueno
- Department of Neurology, Sakai Hospital Kindai University Faculty of Medicine, Sakai, Japan.,Department of Neurology, Kindai University Faculty of Medicine, Osakasayama, Japan
| | - Hikaru Sakamoto
- Department of Neurology, Sakai Hospital Kindai University Faculty of Medicine, Sakai, Japan
| | - Hiroshi Takashima
- 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
| | - Susumu Kusunoki
- Department of Neurology, Kindai University Faculty of Medicine, Osakasayama, Japan
| | - Yusaku Nakamura
- Department of Neurology, Sakai Hospital Kindai University Faculty of Medicine, Sakai, Japan
| |
Collapse
|
54
|
Yuan JH, Hashiguchi A, Okamoto Y, Yoshimura A, Ando M, Shiomi K, Saito K, Takahashi M, Ichinose K, Ohmichi T, Ichikawa K, Tadashi A, Takigawa H, Shibayama H, Takashima H. Clinical and mutational spectrum of Japanese patients with recessive variants in SH3TC2. J Hum Genet 2018; 63:281-287. [PMID: 29321516 DOI: 10.1038/s10038-017-0388-5] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2017] [Revised: 10/12/2017] [Accepted: 10/26/2017] [Indexed: 02/04/2023]
Abstract
SH3TC2, known as the causative gene of autosomal recessive demyelinating Charcot-Marie-Tooth type 4C (CMT4C), was also found linked to a mild mononeuropathy of the median nerve with an autosomal dominant inheritance pattern. Using DNA microarray, Illumina MiSeq, and Ion proton, we carried out gene panel sequencing among 1483 Japanese CMT patients, containing 397 patients with demyelinating CMT. From seven patients with demyelinating CMT, we identified eight recessive variants in the SH3TC2 gene, consisting of five novel (pathogenic/likely pathogenic) and three reported variants. Additionally, from two patients with axonal CMT, we detected a reported recessive variant, p.Arg77Trp, which was herein reclassified as variant with unknown significance. Of the seven CMT4C patients (six females and one male), 2/7 patients developed symptoms at their first decade, and 5/7 patients lost their ambulation around age 50. Scoliosis was observed from more than half (4/7) of these patients, whereas hearing loss is the most common symptom of central nervous system (6/7). No median nerve mononeuropathy was recorded from their family members. We identified recessive variants in SH3TC2 from 1.76% of demyelinating CMT patients. An uncommon gender difference was recognized and the wild spectrum of these variants suggests mutational diversity of SH3TC2 in Japan.
Collapse
Affiliation(s)
- Jun-Hui Yuan
- Department of Neurology and Geriatrics, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima, Japan
| | - Akihiro Hashiguchi
- Department of Neurology and Geriatrics, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima, Japan
| | - Yuji Okamoto
- Department of Neurology and Geriatrics, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima, Japan
| | - Akiko Yoshimura
- Department of Neurology and Geriatrics, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima, Japan
| | - Masahiro Ando
- Department of Neurology and Geriatrics, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima, Japan
| | - Kazutaka Shiomi
- Division of Neurology, Respirology, Endocrinology and Metabolism, Department of Internal Medicine, University of Miyazaki, Miyazaki, Japan
| | - Kayoko Saito
- Institute of Medical Genetics, School of Medicine, Tokyo Women's Medical University, Tokyo, Japan
| | - Makoto Takahashi
- Department of Neurology, Tokyo Medical and Dental University, Tokyo, Japan
| | - Keiko Ichinose
- Department of Neurology, Tokyo Medical and Dental University, Tokyo, Japan
| | - Takuma Ohmichi
- Department of Neurology, NHO Maizuru Medical Center, Kyoto, Japan
| | - Kazushi Ichikawa
- Department of Pediatrics, Odawara Municipal Hospital, Kanagawa, Japan
| | - Adachi Tadashi
- Division of Neurology, Department of Brain and Neurosciences, Faculty of Medicine, Tottori University, Tottori, Japan
| | - Hiroshi Takigawa
- Division of Neurology, Department of Brain and Neurosciences, Faculty of Medicine, Tottori University, Tottori, Japan
| | | | - Hiroshi Takashima
- Department of Neurology and Geriatrics, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima, Japan.
| |
Collapse
|
55
|
Abstract
PURPOSE OF REVIEW Charcot-Marie-Tooth disease (CMT) is one of the commonest inherited neuromuscular diseases with a population prevalence of 1 in 2500. This review will cover recent advances in the genetics and pathomechanisms of CMT and how these are leading to the development of rational therapies. RECENT FINDINGS Pathomechanistic and therapeutic target advances in CMT include the identification of the ErbB receptor signalling pathway as a therapeutic target in CMT1A and pharmacological modification of the unfolded protein response in CMT1B. In CMT2D, due to mutations in glycyl-tRNA synthetase, vascular endothelial growth factor-mediated stimulation of the Nrp1 receptor has been identified as a therapeutic target. Preclinical advances have been accompanied by the publication of large natural history cohorts and the identification of a sensitive biomarker of disease (muscle MRI) that is able to detect disease progression in CMT1A over 1 year. SUMMARY Advances in next-generation sequencing technology, cell biology and animal models of CMT are paving the way for rational treatments. The combination of robust natural history data and the identification of sensitive biomarkers mean that we are now entering an exciting therapeutic era in the field of the genetic neuropathies.
Collapse
|
56
|
|
57
|
Mathis S, Tazir M, Magy L, Duval F, Le Masson G, Duchesne M, Couratier P, Ghorab K, Solé G, Lacoste I, Goizet C, Vallat JM. History and current difficulties in classifying inherited myopathies and muscular dystrophies. J Neurol Sci 2018; 384:50-54. [DOI: 10.1016/j.jns.2017.10.051] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2017] [Revised: 10/30/2017] [Accepted: 10/31/2017] [Indexed: 11/27/2022]
|
58
|
Adachi T, Kawamura K, Furusawa Y, Nishizaki Y, Imanishi N, Umehara S, Izumi K, Suematsu M. Japan's initiative on rare and undiagnosed diseases (IRUD): towards an end to the diagnostic odyssey. Eur J Hum Genet 2017; 25:1025-1028. [PMID: 28794428 PMCID: PMC5558173 DOI: 10.1038/ejhg.2017.106] [Citation(s) in RCA: 58] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2016] [Revised: 05/24/2017] [Accepted: 05/30/2017] [Indexed: 01/01/2023] Open
Abstract
Japan has been facing challenges relating to specifically defined rare diseases, called Nan-Byo in Japanese (literally 'difficult'+'illness'), and has already taken measures for them since 1972. This governmental support has surely benefited Nan-Byo patients; however, those suffering from medically unidentified conditions do not fall into this scheme and thus still confront difficulty in obtaining an examination, a diagnosis, and a treatment. To identify such rare and often undiagnosed diseases, we must integrate systematic diagnosis by medical experts with phenotypic and genetic data matching. Thus, in collaboration with Nan-Byo researchers and the Japanese universal healthcare system, the Japan Agency for Medical Research and Development launched the Initiative on Rare and Undiagnosed Diseases (IRUD) in 2015. IRUD is an ambitious challenge to construct a comprehensive medical network and an internationally compatible data-sharing framework. Synergizing with existing next-generation sequencing capabilities and other infrastructure, the nationwide medical research consortium has successfully grown to accept more than 2000 undiagnosed registrants by December 2016. We also aim at expanding the concept of microattribution throughout the initiative; that is, proper credit as collaborators shall be given to local primary care physicians, nurses and paramedics, patients, their family members, and those supporting the affected individuals whenever appropriate. As it shares many challenges among similar global efforts, IRUD's future successes and lessons learned will significantly contribute to ongoing international endeavors, involving players in basic research, applied research, and societal implementation.
Collapse
Affiliation(s)
- Takeya Adachi
- Japan Agency for Medical Research and Development (AMED), Tokyo, Japan
| | - Kazuo Kawamura
- Japan Agency for Medical Research and Development (AMED), Tokyo, Japan
| | | | - Yuji Nishizaki
- Japan Agency for Medical Research and Development (AMED), Tokyo, Japan
| | - Noriaki Imanishi
- Japan Agency for Medical Research and Development (AMED), Tokyo, Japan
| | - Senkei Umehara
- Japan Agency for Medical Research and Development (AMED), Tokyo, Japan
| | - Kazuo Izumi
- Japan Agency for Medical Research and Development (AMED), Tokyo, Japan
| | - Makoto Suematsu
- Japan Agency for Medical Research and Development (AMED), Tokyo, Japan
| |
Collapse
|
59
|
Fujisawa M, Sano Y, Omoto M, Ogasawara JI, Koga M, Takashima H, Kanda T. Charcot-Marie-Tooth disease type 2 caused by homozygous MME gene mutation superimposed by chronic inflammatory demyelinating polyneuropathy. Rinsho Shinkeigaku 2017; 57:515-520. [PMID: 28855494 DOI: 10.5692/clinicalneurol.cn-001036] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
We report a 59-year-old Japanese male who developed gradually worsening weakness and numbness of distal four extremities since age 50. His parents were first cousins, and blood and cerebral spinal examinations were unremarkable. Homozygous mutation of MME gene was detected and thus he was diagnosed as autosomal-recessive Charcot-Marie-Tooth disease 2T (AR-CMT2T); however, electrophysiological examinations revealed scattered demyelinative changes including elongated terminal latency in several peripheral nerve trunks. Sural nerve biopsy showed endoneurial edema and a lot of thinly myelinated nerve fibers with uneven distribution of remnant myelinated fibers within and between fascicles. Immunoglobulin treatment was initiated considering the possibility of superimposed inflammation and demyelination, and immediate clinical as well as electrophysiological improvements were noted. Our findings indicate that AR-CMT2T caused by MME mutation predisposes to a superimposed inflammatory demyelinating neuropathy. This is the first report which documented the co-existence of CMT2 and chronic inflammatory demyelinating polyneuropathy (CIDP); however, in the peripheral nervous system, neprilysin, a product of MME gene, is more abundant in myelin sheath than in axonal component. The fragility of myelin sheath due to mutated neprilysin may trigger the detrimental immune response against peripheral myelin in this patient.
Collapse
Affiliation(s)
- Miwako Fujisawa
- Department of Neurology and Clinical Neuroscience, Yamaguchi University Graduate School of Medical Science.,Department of Neurology, Yamaguchi Prefectural Grand Medical Center
| | - Yasuteru Sano
- Department of Neurology and Clinical Neuroscience, Yamaguchi University Graduate School of Medical Science
| | - Masatoshi Omoto
- Department of Neurology and Clinical Neuroscience, Yamaguchi University Graduate School of Medical Science
| | - Jyun-Ichi Ogasawara
- Department of Neurology and Clinical Neuroscience, Yamaguchi University Graduate School of Medical Science
| | - Michiaki Koga
- Department of Neurology and Clinical Neuroscience, Yamaguchi University Graduate School of Medical Science
| | - Hiroshi Takashima
- Department of Neurology and Geriatrics Kagoshima University Graduate School of Medical and Dental Sciences
| | - Takashi Kanda
- Department of Neurology and Clinical Neuroscience, Yamaguchi University Graduate School of Medical Science
| |
Collapse
|
60
|
Ando M, Okamoto Y, Yoshimura A, Yuan JH, Hiramatsu Y, Higuchi Y, Hashiguchi A, Mitsui J, Ishiura H, Fukumura S, Matsushima M, Ochi N, Tsugawa J, Morishita S, Tsuji S, Takashima H. Clinical and mutational spectrum of Charcot-Marie-Tooth disease type 2Z caused by MORC2 variants in Japan. Eur J Neurol 2017; 24:1274-1282. [PMID: 28771897 DOI: 10.1111/ene.13360] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2017] [Accepted: 06/12/2017] [Indexed: 01/15/2023]
Abstract
BACKGROUND AND PURPOSE The microrchidia family CW-type zinc finger 2 gene (MORC2) was newly identified as a causative gene of Charcot-Marie-Tooth disease (CMT) type 2Z in 2016. We aimed to describe the clinical and mutational spectrum of patients with CMT harboring MORC2 mutations in Japan. METHODS We analyzed samples from 781 unrelated patients clinically diagnosed with CMT using deoxyribonucleic acid microarray or targeted resequencing by next-generation sequencing, and samples from 434 mutation-negative patients were subjected to whole-exome sequencing. We extracted MORC2 variants from these whole-exome sequencing data and classified them according to American College of Medical Genetics standards and guidelines. RESULTS We identified MORC2 variants in 13 patients. As the second most common causative gene of CMT type 2 after MFN2, MORC2 variants were detected in 2.7% of patients with CMT type 2. The mean age of onset was 10.3 ± 8.7 years, and the inheritance pattern was mostly sporadic (11/13 patients, 84.6%). The clinical phenotype was typically length-dependent polyneuropathy, and electrophysiological studies revealed sensory-dominant axonal neuropathy. Mental retardation was identified in 4/13 patients (30.8%). p.Arg190Trp, as a mutational hotspot, was observed in eight unrelated families. We also identified two novel probably pathogenic variants, p.Cys345Tyr and p.Ala369Val, and one novel uncertain significance variant, p.Tyr332Cys. CONCLUSIONS Our study is the largest report of patients harboring MORC2 variants. We revealed a clinical and mutational spectrum of Japanese patients with MORC2 variants. More attention should be paid to cognitive impairment, and the responsible mechanism requires further research for elucidation.
Collapse
Affiliation(s)
- M Ando
- Department of Neurology and Geriatrics, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima
| | - Y Okamoto
- Department of Neurology and Geriatrics, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima
| | - A Yoshimura
- Department of Neurology and Geriatrics, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima
| | - J-H Yuan
- Department of Neurology and Geriatrics, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima
| | - Y Hiramatsu
- Department of Neurology and Geriatrics, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima
| | - Y Higuchi
- Department of Neurology and Geriatrics, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima
| | - A Hashiguchi
- Department of Neurology and Geriatrics, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima
| | - J Mitsui
- Department of Neurology, Graduate School of Medicine, The University of Tokyo, Tokyo
| | - H Ishiura
- Department of Neurology, Graduate School of Medicine, The University of Tokyo, Tokyo
| | - S Fukumura
- Department of Pediatrics, School of Medicine, Sapporo Medical University, Sapporo
| | - M Matsushima
- Department of Neurology, Hokkaido University Graduate School of Medicine, Sapporo
| | - N Ochi
- Aichi Prefectural Mikawa Aoitori and Rehabilitation Center for Developmental Disabilities, Aichi
| | - J Tsugawa
- Department of Neurology, Fukuoka University Faculty of Medicine, Fukuoka
| | - S Morishita
- Department of Computational Biology and Medical Sciences, Graduate School of Frontier Sciences, The University of Tokyo, Chiba, Japan
| | - S Tsuji
- Department of Neurology, Graduate School of Medicine, The University of Tokyo, Tokyo
| | - H Takashima
- Department of Neurology and Geriatrics, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima
| |
Collapse
|
61
|
Ando M, Hashiguchi A, Okamoto Y, Yoshimura A, Hiramatsu Y, Yuan J, Higuchi Y, Mitsui J, Ishiura H, Umemura A, Maruyama K, Matsushige T, Morishita S, Nakagawa M, Tsuji S, Takashima H. Clinical and genetic diversities of Charcot-Marie-Tooth disease with MFN2 mutations in a large case study. J Peripher Nerv Syst 2017; 22:191-199. [PMID: 28660751 PMCID: PMC5697682 DOI: 10.1111/jns.12228] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2017] [Revised: 06/21/2017] [Accepted: 06/22/2017] [Indexed: 11/28/2022]
Abstract
Charcot-Marie-Tooth disease (CMT) constitutes a heterogeneous group affecting motor and sensory neurons in the peripheral nervous system. MFN2 mutations are the most common cause of axonal CMT. We describe the clinical and mutational spectra of CMT patients harboring MFN2 mutations in Japan. We analyzed 1,334 unrelated patients with clinically suspected CMT referred by neurological and neuropediatric departments throughout Japan. We conducted mutation screening using a DNA microarray, targeted resequencing, and whole-exome sequencing. We identified pathogenic or likely pathogenic MFN2 variants from 79 CMT patients, comprising 44 heterozygous and 1 compound heterozygous variants. A total of 15 novel variants were detected. An autosomal dominant family history was determined in 43 cases, and the remaining 36 cases were reported as sporadic with no family history. The mean onset age of CMT in these patients was 12 ± 14 (range 0-59) years. We observed neuropathic symptoms in all patients. Some had optic atrophy, vocal cord paralysis, or spasticity. We detected a compound heterozygous MFN2 mutation in a patient with a severe phenotype and the co-occurrence of MFN2 and PMP22 mutations in a patient with an uncommon phenotype. MFN2 is the most frequent causative gene of CMT2 in Japan. We present 15 novel variants and broad clinical and mutational spectra of Japanese MFN2-related CMT patients. Regardless of the onset age and inheritance pattern, MFN2 gene analysis should be performed. Combinations of causative genes should be considered to explain the phenotypic diversity.
Collapse
Affiliation(s)
- Masahiro Ando
- 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
| | - Yuji Okamoto
- 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
| | - Yu Hiramatsu
- Department of Neurology and Geriatrics, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima, Japan
| | - Junhui Yuan
- 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 Mitsui
- Department of Neurology, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan
| | - Hiroyuki Ishiura
- Department of Neurology, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan
| | - Ayako Umemura
- Department of Pediatric Neurology, Aichi Prefectural Colony Central Hospital, Aichi, Japan
| | - Koichi Maruyama
- Department of Pediatric Neurology, Aichi Prefectural Colony Central Hospital, Aichi, Japan
| | - Takeshi Matsushige
- Department of Pediatrics, Yamaguchi University Graduate School of Medicine, Yamaguchi, Japan
| | - Shinichi Morishita
- Department of Computational Biology and Medical Sciences, Graduate School of Frontier Sciences, The University of Tokyo, Chiba, Japan
| | - Masanori Nakagawa
- Department of Neurology, North Medical Center, Kyoto Prefectural University of Medicine, Kyoto, Japan
| | - Shoji Tsuji
- Department of Neurology, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan
| | - Hiroshi Takashima
- Department of Neurology and Geriatrics, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima, Japan
| |
Collapse
|
62
|
Nishihara H, Omoto M, Takao M, Higuchi Y, Koga M, Kawai M, Kawano H, Ikeda E, Takashima H, Kanda T. Autopsy case of the C12orf65 mutation in a patient with signs of mitochondrial dysfunction. NEUROLOGY-GENETICS 2017; 3:e171. [PMID: 28804760 PMCID: PMC5532748 DOI: 10.1212/nxg.0000000000000171] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/06/2017] [Accepted: 05/08/2017] [Indexed: 11/16/2022]
Abstract
Objective: To describe the autopsy case of a patient with a homozygous 2-base deletion, c171_172delGA (p.N58fs), in the C12orf65 gene. Methods: We described the clinical history, neuroimaging data, neuropathology, and genetic analysis of the patients with C12orf65 mutations. Results: The patient was a Japanese woman with a history of delayed psychomotor development, primary amenorrhea, and gait disturbance in her 20s. She was hospitalized because of respiratory failure at the age of 60. Pectus excavatum, long fingers and toes, and pes cavus were revealed by physical examination. Her IQ score was 44. Neurologic examination revealed ophthalmoplegia, optic atrophy, dysphagia, distal dominant muscle weakness and atrophy, hyperreflexia at patellar tendon reflex, hyporeflexia at Achilles tendon reflex, and extensor plantar reflexes. At age 60, she died of pneumonia. Lactate levels were elevated in the patient's serum and CSF. T2-weighted brain MRI showed symmetrical hyperintense brainstem lesions. At autopsy, axial sections exposed symmetrical cyst formation with brownish lesions in the upper spinal cord, ventral medulla, pons, dorsal midbrain, and medial hypothalamus. Microscopic analysis of these areas demonstrated mild gliosis with rarefaction. Cell bodies in the choroid plexuses were eosinophilic and swollen. Electron microscopic examination revealed that these cells contained numerous abnormal mitochondria. Whole-exome sequencing revealed the 2-base deletion in C12orf65. Conclusions: We report an autopsy case of the C12orf65 mutation, and findings suggest that mitochondrial dysfunction may underlie the unique clinical presentations.
Collapse
Affiliation(s)
- Hideaki Nishihara
- Department of Neurology and Clinical Neuroscience (H.N., M.O., M. Koga, M. Kawai, T.K.), Department of Laboratory Science (H.K.), Department of Pathology (E.I.), Yamaguchi University Graduate School of Medicine, Japan; Department of Neurology and Cerebrovascular Medicine (M.T.), Saitama International Medical Center, Saitama Medical University, Japan; and Department of Neurology and Geriatrics (Y.H., H.T.), Kagoshima University Graduate School of Medical and Dental Sciences, Japan
| | - Masatoshi Omoto
- Department of Neurology and Clinical Neuroscience (H.N., M.O., M. Koga, M. Kawai, T.K.), Department of Laboratory Science (H.K.), Department of Pathology (E.I.), Yamaguchi University Graduate School of Medicine, Japan; Department of Neurology and Cerebrovascular Medicine (M.T.), Saitama International Medical Center, Saitama Medical University, Japan; and Department of Neurology and Geriatrics (Y.H., H.T.), Kagoshima University Graduate School of Medical and Dental Sciences, Japan
| | - Masaki Takao
- Department of Neurology and Clinical Neuroscience (H.N., M.O., M. Koga, M. Kawai, T.K.), Department of Laboratory Science (H.K.), Department of Pathology (E.I.), Yamaguchi University Graduate School of Medicine, Japan; Department of Neurology and Cerebrovascular Medicine (M.T.), Saitama International Medical Center, Saitama Medical University, Japan; and Department of Neurology and Geriatrics (Y.H., H.T.), Kagoshima University Graduate School of Medical and Dental Sciences, Japan
| | - Yujiro Higuchi
- Department of Neurology and Clinical Neuroscience (H.N., M.O., M. Koga, M. Kawai, T.K.), Department of Laboratory Science (H.K.), Department of Pathology (E.I.), Yamaguchi University Graduate School of Medicine, Japan; Department of Neurology and Cerebrovascular Medicine (M.T.), Saitama International Medical Center, Saitama Medical University, Japan; and Department of Neurology and Geriatrics (Y.H., H.T.), Kagoshima University Graduate School of Medical and Dental Sciences, Japan
| | - Michiaki Koga
- Department of Neurology and Clinical Neuroscience (H.N., M.O., M. Koga, M. Kawai, T.K.), Department of Laboratory Science (H.K.), Department of Pathology (E.I.), Yamaguchi University Graduate School of Medicine, Japan; Department of Neurology and Cerebrovascular Medicine (M.T.), Saitama International Medical Center, Saitama Medical University, Japan; and Department of Neurology and Geriatrics (Y.H., H.T.), Kagoshima University Graduate School of Medical and Dental Sciences, Japan
| | - Motoharu Kawai
- Department of Neurology and Clinical Neuroscience (H.N., M.O., M. Koga, M. Kawai, T.K.), Department of Laboratory Science (H.K.), Department of Pathology (E.I.), Yamaguchi University Graduate School of Medicine, Japan; Department of Neurology and Cerebrovascular Medicine (M.T.), Saitama International Medical Center, Saitama Medical University, Japan; and Department of Neurology and Geriatrics (Y.H., H.T.), Kagoshima University Graduate School of Medical and Dental Sciences, Japan
| | - Hiroo Kawano
- Department of Neurology and Clinical Neuroscience (H.N., M.O., M. Koga, M. Kawai, T.K.), Department of Laboratory Science (H.K.), Department of Pathology (E.I.), Yamaguchi University Graduate School of Medicine, Japan; Department of Neurology and Cerebrovascular Medicine (M.T.), Saitama International Medical Center, Saitama Medical University, Japan; and Department of Neurology and Geriatrics (Y.H., H.T.), Kagoshima University Graduate School of Medical and Dental Sciences, Japan
| | - Eiji Ikeda
- Department of Neurology and Clinical Neuroscience (H.N., M.O., M. Koga, M. Kawai, T.K.), Department of Laboratory Science (H.K.), Department of Pathology (E.I.), Yamaguchi University Graduate School of Medicine, Japan; Department of Neurology and Cerebrovascular Medicine (M.T.), Saitama International Medical Center, Saitama Medical University, Japan; and Department of Neurology and Geriatrics (Y.H., H.T.), Kagoshima University Graduate School of Medical and Dental Sciences, Japan
| | - Hiroshi Takashima
- Department of Neurology and Clinical Neuroscience (H.N., M.O., M. Koga, M. Kawai, T.K.), Department of Laboratory Science (H.K.), Department of Pathology (E.I.), Yamaguchi University Graduate School of Medicine, Japan; Department of Neurology and Cerebrovascular Medicine (M.T.), Saitama International Medical Center, Saitama Medical University, Japan; and Department of Neurology and Geriatrics (Y.H., H.T.), Kagoshima University Graduate School of Medical and Dental Sciences, Japan
| | - Takashi Kanda
- Department of Neurology and Clinical Neuroscience (H.N., M.O., M. Koga, M. Kawai, T.K.), Department of Laboratory Science (H.K.), Department of Pathology (E.I.), Yamaguchi University Graduate School of Medicine, Japan; Department of Neurology and Cerebrovascular Medicine (M.T.), Saitama International Medical Center, Saitama Medical University, Japan; and Department of Neurology and Geriatrics (Y.H., H.T.), Kagoshima University Graduate School of Medical and Dental Sciences, Japan
| |
Collapse
|
63
|
Liu L, Li XB, Hu ZHM, Zi XH, Zhao X, Xie YZ, Huang SHX, Xia K, Tang BS, Zhang RX. Phenotypes and cellular effects of GJB1 mutations causing CMT1X in a cohort of 226 Chinese CMT families. Clin Genet 2017; 91:881-891. [PMID: 27804109 DOI: 10.1111/cge.12913] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2016] [Revised: 10/26/2016] [Accepted: 10/28/2016] [Indexed: 12/23/2022]
Abstract
The aim of this study is to explore the phenotypic and genotypic features of X-linked Charcot-Marie-Tooth (CMT) disease in the mainland of China and to study the cellular effects of six novel Gap junction protein beta-1 variants. We identified 25 missense and 1 non-sense mutations of GJB1 in 31 unrelated families out of 226 CMT families. The frequency of GJB1 mutations was 13.7% of the total and 65% of intermediate CMT. Six novel GJB1 variants (c.5A>G, c.8G>A, c.242T>C, c.269T>C, c.317T>C and c.434T>G) were detected in six unrelated intermediate CMT families. Fluorescence revealed that HeLa cells transfected with EGFP-GJB1-V74M, EGFP-GJB1-L81P or EGFP-GJB1-L90P had diffuse endoplasmic reticulum staining, HeLa cells transfected with EGFP-GJB1-L106P had diffuse intracellular staining, and HeLa cells transfected with EGFP-GJB1-N2S had cytoplasmic and nuclear staining. The distribution of Cx32 in HeLa cells transfected with EGFP-GJB1-F145C was similar to that of those transfected with wild-type (WT). These six variants resulted in a higher percentage of apoptosis than did WT as detected by flow cytometry and Hoechst staining. In conclusion, mutation screening should be first performed in intermediate CMT patients, especially those with additional features. The novel GJB1 variants c.5A>G, c.8G>A, c.242T>C and c.269T>C are considered pathogenic, and c.317T>C and c.434T>G are classified as probably pathogenic.
Collapse
Affiliation(s)
- L Liu
- Department of Neurology, The Third Xiangya Hospital, Central South University, Changsha, China
| | - X B Li
- Department of Neurology, The Third Xiangya Hospital, Central South University, Changsha, China
| | - Z H M Hu
- National Key Lab of Medical Genetics, Central South University, Changsha, China
| | - X H Zi
- Department of Neurology, The Third Xiangya Hospital, Central South University, Changsha, China
| | - X Zhao
- Department of Neurology, The Third Xiangya Hospital, Central South University, Changsha, China
| | - Y Z Xie
- Department of Neurology, The Third Xiangya Hospital, Central South University, Changsha, China
| | - S H X Huang
- Department of Neurology, The Third Xiangya Hospital, Central South University, Changsha, China
| | - K Xia
- National Key Lab of Medical Genetics, Central South University, Changsha, China
| | - B S Tang
- National Key Lab of Medical Genetics, Central South University, Changsha, China
- Department of Neurology, Xiangya Hospital, Central South University, Changsha, China
| | - R X Zhang
- Department of Neurology, The Third Xiangya Hospital, Central South University, Changsha, China
| |
Collapse
|
64
|
Yoshimura A, Yuan JH, Hashiguchi A, Hiramatsu Y, Ando M, Higuchi Y, Nakamura T, Okamoto Y, Matsumura K, Hamano T, Sawaura N, Shimatani Y, Kumada S, Okumura Y, Miyahara J, Yamaguchi Y, Kitamura S, Haginoya K, Mitsui J, Ishiura H, Tsuji S, Takashima H. Clinical and mutational spectrum of Japanese patients with Charcot-Marie-Tooth disease caused by GDAP1 variants. Clin Genet 2017; 92:274-280. [PMID: 28244113 DOI: 10.1111/cge.13002] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2016] [Revised: 02/09/2017] [Accepted: 02/23/2017] [Indexed: 12/13/2022]
Abstract
BACKGROUND Mutations in GDAP1 are responsible for heterogeneous clinical and electrophysiological phenotypes of Charcot-Marie-Tooth disease (CMT), with autosomal dominant or recessive inheritance pattern. The aim of this study is to identify the clinical and mutational spectrum of CMT patients with GDAP1 variants in Japan. MATERIALS AND METHODS From April 2007 to October 2014, using three state-of-art technologies, we conducted gene panel sequencing in a cohort of 1,030 patients with inherited peripheral neuropathies (IPNs), and 398 mutation-negative cases were further analyzed with whole-exome sequencing. RESULTS We identified GDAP1 variants from 10 patients clinically diagnosed with CMT. The most frequent recessive variant in our cohort (5/10), c.740C>T (p.A247V), was verified to be associated with a founder event. We also detected three novel likely pathogenic variants: c.928C>T (p.R310W) and c.546delA (p.E183Kfs*23) in Case 2 and c.376G>A (p.E126K) in Case 8. Nerve conduction study or sural nerve biopsy of all 10 patients indicated axonal type peripheral neuropathy. CONCLUSION We identified GDAP1 variants in approximately 1% of our cohort with IPNs, and established a founder mutation in half of these patients. Our study originally described the mutational spectrum and clinical features of GDAP1-related CMT patients in Japan.
Collapse
Affiliation(s)
- A Yoshimura
- Department of Neurology and Geriatrics, Kagoshima University, Graduate School of Medical and Dental Sciences, Kagoshima, Japan
| | - J-H Yuan
- Department of Neurology and Geriatrics, Kagoshima University, Graduate School of Medical and Dental Sciences, Kagoshima, Japan
| | - A Hashiguchi
- Department of Neurology and Geriatrics, Kagoshima University, Graduate School of Medical and Dental Sciences, Kagoshima, Japan
| | - Y Hiramatsu
- Department of Neurology and Geriatrics, Kagoshima University, Graduate School of Medical and Dental Sciences, Kagoshima, Japan
| | - M Ando
- Department of Neurology and Geriatrics, Kagoshima University, Graduate School of Medical and Dental Sciences, Kagoshima, Japan
| | - Y Higuchi
- Department of Neurology and Geriatrics, Kagoshima University, Graduate School of Medical and Dental Sciences, Kagoshima, Japan
| | - T Nakamura
- Department of Neurology and Geriatrics, Kagoshima University, Graduate School of Medical and Dental Sciences, Kagoshima, Japan
| | - Y Okamoto
- Department of Neurology and Geriatrics, Kagoshima University, Graduate School of Medical and Dental Sciences, Kagoshima, Japan
| | - K Matsumura
- Department of Neurology, Teikyo University, Tokyo, Japan
| | - T Hamano
- Department of Neurology, Kansai Electric Power Hospital, Osaka, Japan
| | - N Sawaura
- Department of Pediatrics, Gunma University Graduate School of Medicine, Gunma, Japan
| | - Y Shimatani
- Department of Clinical Neuroscience, Tokushima University Graduate School, Tokushima, Japan
| | - S Kumada
- Department of Neuropediatrics, Tokyo Metropolitan Neurological Hospital, Tokyo, Japan
| | - Y Okumura
- Department of Pediatric Neurology, Shizuoka Children's Hospital, Shizuoka, Japan
| | - J Miyahara
- Department of Neurology, Tominaga Hospital, Osaka, Japan
| | - Y Yamaguchi
- Department of Neurology, Hematology, Metabolism, Endocrinology and Diabetology, Yamagata University Faculty of Medicine, Yamagata, Japan
| | - S Kitamura
- Department of Neurology, Konan Hospital, Hyogo, Japan
| | - K Haginoya
- Department of Pediatric Neurology, Miyagi Children's Hospital, Miyagi, Japan
| | - J Mitsui
- Department of Neurology, Graduate School of Medicine, University of Tokyo, Tokyo, Japan
| | - H Ishiura
- Department of Neurology, Graduate School of Medicine, University of Tokyo, Tokyo, Japan
| | - S Tsuji
- Department of Neurology, Graduate School of Medicine, University of Tokyo, Tokyo, Japan
| | - H Takashima
- Department of Neurology and Geriatrics, Kagoshima University, Graduate School of Medical and Dental Sciences, Kagoshima, Japan
| |
Collapse
|
65
|
Weis J, Claeys KG, Roos A, Azzedine H, Katona I, Schröder JM, Senderek J. Towards a functional pathology of hereditary neuropathies. Acta Neuropathol 2017; 133:493-515. [PMID: 27896434 DOI: 10.1007/s00401-016-1645-y] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2016] [Revised: 11/10/2016] [Accepted: 11/13/2016] [Indexed: 12/11/2022]
Abstract
A growing number of hereditary neuropathies have been assigned to causative gene defects in recent years. The study of human nerve biopsy samples has contributed substantially to the discovery of many of these neuropathy genes. Genotype-phenotype correlations based on peripheral nerve pathology have provided a comprehensive picture of the consequences of these mutations. Intriguingly, several gene defects lead to distinguishable lesion patterns that can be studied in nerve biopsies. These characteristic features include the loss of certain nerve fiber populations and a large spectrum of distinct structural changes of axons, Schwann cells and other components of peripheral nerves. In several instances the lesion patterns are directly or indirectly linked to the known functions of the mutated gene. The present review is designed to provide an overview on these characteristic patterns. It also considers other aspects important for the manifestation and pathology of hereditary neuropathies including the role of inflammation, effects of chemotherapeutic agents and alterations detectable in skin biopsies.
Collapse
Affiliation(s)
- Joachim Weis
- Institute of Neuropathology, RWTH Aachen University Medical School, Pauwelsstr. 30, 52074, Aachen, Germany.
| | - Kristl G Claeys
- Institute of Neuropathology, RWTH Aachen University Medical School, Pauwelsstr. 30, 52074, Aachen, Germany
- Department of Neurology, RWTH Aachen University Medical School, Pauwelsstr. 30, 52074, Aachen, Germany
- Department of Neurology, University Hospitals Leuven and University of Leuven (KU Leuven), Leuven, Belgium
| | - Andreas Roos
- Institute of Neuropathology, RWTH Aachen University Medical School, Pauwelsstr. 30, 52074, Aachen, Germany
- Leibniz-Institut für Analytische Wissenschaften-ISAS-e.V., Otto-Hahn-Str. 6b, 44227, Dortmund, Germany
| | - Hamid Azzedine
- Institute of Neuropathology, RWTH Aachen University Medical School, Pauwelsstr. 30, 52074, Aachen, Germany
| | - Istvan Katona
- Institute of Neuropathology, RWTH Aachen University Medical School, Pauwelsstr. 30, 52074, Aachen, Germany
| | - J Michael Schröder
- Institute of Neuropathology, RWTH Aachen University Medical School, Pauwelsstr. 30, 52074, Aachen, Germany
| | - Jan Senderek
- Friedrich-Baur-Institute, Department of Neurology, Ludwig-Maximilians-University, Ziemssenstr. 1a, 80336, Munich, Germany.
| |
Collapse
|
66
|
Abstract
Neprilysin has a major role in both the generation and degradation of bioactive peptides. LCZ696 (valsartan/sacubitril, Entresto), the first of the new ARNI (dual-acting angiotensin-receptor-neprilysin inhibitor) drug class, contains equimolar amounts of valsartan, an angiotensin-receptor blocker, and sacubitril, a prodrug for the neprilysin inhibitor LBQ657. LCZ696 reduced blood pressure more than valsartan alone in patients with hypertension. In the PARADIGM-HF study, LCZ696 was superior to the angiotensin-converting enzyme inhibitor enalapril for the treatment of heart failure with reduced ejection fraction, and LCZ696 was approved by the FDA for this purpose in 2015. This approval was the first for chronic neprilysin inhibition. The many peptides metabolized by neprilysin suggest many potential consequences of chronic neprilysin inhibitor therapy, both beneficial and adverse. Moreover, LBQ657 might inhibit enzymes other than neprilysin. Chronic neprilysin inhibition might have an effect on angio-oedema, bronchial reactivity, inflammation, and cancer, and might predispose to polyneuropathy. Additionally, inhibition of neprilysin metabolism of amyloid-β peptides might have an effect on Alzheimer disease, age-related macular degeneration, and cerebral amyloid angiopathy. Much of the evidence for possible adverse consequences of chronic neprilysin inhibition comes from studies in animal models, and the relevance of this evidence to humans is unknown. This Review summarizes current knowledge of neprilysin function and possible consequences of chronic neprilysin inhibition that indicate a need for vigilance in the use of neprilysin inhibitor therapy.
Collapse
Affiliation(s)
- Duncan J Campbell
- St Vincent's Institute of Medical Research, 41 Victoria Parade, Fitzroy, Victoria 3065, Australia.,University of Melbourne, Parkville, Melbourne, Victoria 3010, Australia
| |
Collapse
|
67
|
Bacchelli E, Cainazzo MM, Cameli C, Guerzoni S, Martinelli A, Zoli M, Maestrini E, Pini LA. A genome-wide analysis in cluster headache points to neprilysin and PACAP receptor gene variants. J Headache Pain 2016; 17:114. [PMID: 27957625 PMCID: PMC5153392 DOI: 10.1186/s10194-016-0705-y] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2016] [Accepted: 11/29/2016] [Indexed: 01/03/2023] Open
Abstract
Background Cluster Headache (CH) is a severe primary headache, with a poorly understood pathophysiology. Complex genetic factors are likely to play a role in CH etiology; however, no confirmed gene associations have been identified. The aim of this study is to identify genetic variants influencing risk to CH and to explore the potential pathogenic mechanisms. Methods We have performed a genome-wide association study (GWAS) in a clinically well-defined cohort of 99 Italian patients with CH and in a control sample of 360 age-matched sigarette smoking healthy individuals, using the Infinium PsychArray (Illumina), which combines common highly-informative genome-wide tag SNPs and exonic SNPs. Genotype data were used to carry out a genome-wide single marker case-control association analysis using common SNPs, and a gene-based association analysis focussing on rare protein altering variants in 745 candidate genes with a putative role in CH. Results Although no single variant showed statistically significant association at the genome-wide threshold, we identified an interesting suggestive association (P = 9.1 × 10−6) with a common variant of the PACAP receptor gene (ADCYAP1R1). Furthermore, gene-based analysis provided significant evidence of association (P = 2.5 × 10−5) for a rare potentially damaging missense variant in the MME gene, encoding for the membrane metallo-endopeptidase neprilysin. Conclusions Our study represents the first genome-wide association study of common SNPs and rare exonic variants influencing risk for CH. The most interesting results implicate ADCYAP1R1 and MME gene variants in CH susceptibility and point to a role for genes involved in pain processing. These findings provide new insights into the pathogenesis of CH that need further investigation and replication in larger CH samples. Electronic supplementary material The online version of this article (doi:10.1186/s10194-016-0705-y) contains supplementary material, which is available to authorized users.
Collapse
Affiliation(s)
- Elena Bacchelli
- Department of Pharmacy and Biotechnology, University of Bologna, Via Selmi 3, 40126, Bologna, Italy
| | - Maria Michela Cainazzo
- Headache and Drug Abuse Unit, Policlinico Hospital, University of Modena and Reggio Emilia, Modena, Italy
| | - Cinzia Cameli
- Department of Pharmacy and Biotechnology, University of Bologna, Via Selmi 3, 40126, Bologna, Italy
| | - Simona Guerzoni
- Headache and Drug Abuse Unit, Policlinico Hospital, University of Modena and Reggio Emilia, Modena, Italy
| | - Angela Martinelli
- Department of Pharmacy and Biotechnology, University of Bologna, Via Selmi 3, 40126, Bologna, Italy.,Present address: School of Medicine, University of St Andrews, St Andrews, UK
| | - Michele Zoli
- Department of Biomedical, Metabolic and Neural Sciences, Center for Neuroscience and Neurotechnology, University of Modena and Reggio Emilia, Modena, Italy
| | - Elena Maestrini
- Department of Pharmacy and Biotechnology, University of Bologna, Via Selmi 3, 40126, Bologna, Italy.
| | - Luigi Alberto Pini
- Center for Neuroscience and Neurotechnology, Policlinico Hospital, University of Modena and Reggio Emilia, Via del Pozzo 71, 41100, Modena, Italy.
| |
Collapse
|
68
|
Higuchi Y, Yuan J, Takashima H. Reply. Ann Neurol 2016; 80:477-8. [DOI: 10.1002/ana.24742] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2016] [Accepted: 07/25/2016] [Indexed: 11/09/2022]
Affiliation(s)
- Yujiro Higuchi
- Department of Neurology and GeriatricsKagoshima University Graduate School of Medical and Dental SciencesKagoshima Japan
| | - Junhui Yuan
- Department of Neurology and GeriatricsKagoshima University Graduate School of Medical and Dental SciencesKagoshima Japan
| | - Hiroshi Takashima
- Department of Neurology and GeriatricsKagoshima University Graduate School of Medical and Dental SciencesKagoshima Japan
| |
Collapse
|
69
|
Auer-Grumbach M, Toegel S, Schabhüttl M, Weinmann D, Chiari C, Bennett D, Beetz C, Klein D, Andersen P, Böhme I, Fink-Puches R, Gonzalez M, Harms M, Motley W, Reilly M, Renner W, Rudnik-Schöneborn S, Schlotter-Weigel B, Themistocleous A, Weishaupt J, Ludolph A, Wieland T, Tao F, Abreu L, Windhager R, Zitzelsberger M, Strom T, Walther T, Scherer S, Züchner S, Martini R, Senderek J. Rare Variants in MME, Encoding Metalloprotease Neprilysin, Are Linked to Late-Onset Autosomal-Dominant Axonal Polyneuropathies. Am J Hum Genet 2016; 99:607-623. [PMID: 27588448 DOI: 10.1016/j.ajhg.2016.07.008] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2016] [Accepted: 07/07/2016] [Indexed: 12/11/2022] Open
Abstract
Axonal polyneuropathies are a frequent cause of progressive disability in the elderly. Common etiologies comprise diabetes mellitus, paraproteinaemia, and inflammatory disorders, but often the underlying causes remain elusive. Late-onset axonal Charcot-Marie-Tooth neuropathy (CMT2) is an autosomal-dominantly inherited condition that manifests in the second half of life and is genetically largely unexplained. We assumed age-dependent penetrance of mutations in a so far unknown gene causing late-onset CMT2. We screened 51 index case subjects with late-onset CMT2 for mutations by whole-exome (WES) and Sanger sequencing and subsequently queried WES repositories for further case subjects carrying mutations in the identified candidate gene. We studied nerve pathology and tissue levels and function of the abnormal protein in order to explore consequences of the mutations. Altogether, we observed heterozygous rare loss-of-function and missense mutations in MME encoding the metalloprotease neprilysin in 19 index case subjects diagnosed with axonal polyneuropathies or neurodegenerative conditions involving the peripheral nervous system. MME mutations segregated in an autosomal-dominant fashion with age-related incomplete penetrance and some affected individuals were isolated case subjects. We also found that MME mutations resulted in strongly decreased tissue availability of neprilysin and impaired enzymatic activity. Although neprilysin is known to degrade β-amyloid, we observed no increased amyloid deposition or increased incidence of dementia in individuals with MME mutations. Detection of MME mutations is expected to increase the diagnostic yield in late-onset polyneuropathies, and it will be tempting to explore whether substances that can elevate neprilysin activity could be a rational option for treatment.
Collapse
|
70
|
Depondt C, Donatello S, Rai M, Wang FC, Manto M, Simonis N, Pandolfo M. MME mutation in dominant spinocerebellar ataxia with neuropathy (SCA43). NEUROLOGY-GENETICS 2016; 2:e94. [PMID: 27583304 PMCID: PMC4991603 DOI: 10.1212/nxg.0000000000000094] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/07/2016] [Accepted: 07/01/2016] [Indexed: 12/31/2022]
Abstract
Objective: To identify the causative gene mutation in a 5-generation Belgian family with dominantly inherited spinocerebellar ataxia and polyneuropathy, in which known genetic etiologies had been excluded. Methods: We collected DNA samples of 28 family members, including 7 living affected individuals, whose clinical records were reviewed by a neurologist experienced in ataxia. We combined linkage data of 21 family members with whole exome sequencing in 2 affected individuals to identify shared heterozygous variants mapping to potentially linked regions. Variants were screened for rarity and for predicted damaging effect. A candidate mutation was confirmed by Sanger sequencing and tested for cosegregation with the disease. Results: Affected individuals presented with late-onset sensorimotor axonal polyneuropathy; all but one also had cerebellar ataxia. We identified a variant in the MME gene, p.C143Y, that was absent from control databases, cosegregated with the phenotype, and was predicted to have a strong damaging effect on the encoded protein by all algorithms we used. Conclusions: MME encodes neprilysin (NEP), a zinc-dependent metalloprotease expressed in most tissues, including the central and peripheral nervous systems. The mutated cysteine 143 forms a disulfide bridge, which is 100% conserved in NEP and in similar enzymes. The recent identification of recessive MME mutations in 10 unrelated individuals from Japan with axonal polyneuropathy further supports the causality of the mutation, despite the dominant mode of inheritance and the presence of cerebellar involvement in our study family. Functional studies are needed to identify the mechanisms underlying these differences.
Collapse
Affiliation(s)
- Chantal Depondt
- Department of Neurology (C.D., M.M., M.P.), Department of Medical Genetics (N.S.), Hôpital Erasme, Laboratory of Experimental Neurology (C.D., S.D., M.R., M.M.), Université Libre de Bruxelles; Department of Physical Medicine and Rehabilitation (F.C.W.), University of Liège, University Hospital; and Fonds National de la Recherche Scientifique (M.M.), Brussels, Belgium
| | - Simona Donatello
- Department of Neurology (C.D., M.M., M.P.), Department of Medical Genetics (N.S.), Hôpital Erasme, Laboratory of Experimental Neurology (C.D., S.D., M.R., M.M.), Université Libre de Bruxelles; Department of Physical Medicine and Rehabilitation (F.C.W.), University of Liège, University Hospital; and Fonds National de la Recherche Scientifique (M.M.), Brussels, Belgium
| | - Myriam Rai
- Department of Neurology (C.D., M.M., M.P.), Department of Medical Genetics (N.S.), Hôpital Erasme, Laboratory of Experimental Neurology (C.D., S.D., M.R., M.M.), Université Libre de Bruxelles; Department of Physical Medicine and Rehabilitation (F.C.W.), University of Liège, University Hospital; and Fonds National de la Recherche Scientifique (M.M.), Brussels, Belgium
| | - François Charles Wang
- Department of Neurology (C.D., M.M., M.P.), Department of Medical Genetics (N.S.), Hôpital Erasme, Laboratory of Experimental Neurology (C.D., S.D., M.R., M.M.), Université Libre de Bruxelles; Department of Physical Medicine and Rehabilitation (F.C.W.), University of Liège, University Hospital; and Fonds National de la Recherche Scientifique (M.M.), Brussels, Belgium
| | - Mario Manto
- Department of Neurology (C.D., M.M., M.P.), Department of Medical Genetics (N.S.), Hôpital Erasme, Laboratory of Experimental Neurology (C.D., S.D., M.R., M.M.), Université Libre de Bruxelles; Department of Physical Medicine and Rehabilitation (F.C.W.), University of Liège, University Hospital; and Fonds National de la Recherche Scientifique (M.M.), Brussels, Belgium
| | - Nicolas Simonis
- Department of Neurology (C.D., M.M., M.P.), Department of Medical Genetics (N.S.), Hôpital Erasme, Laboratory of Experimental Neurology (C.D., S.D., M.R., M.M.), Université Libre de Bruxelles; Department of Physical Medicine and Rehabilitation (F.C.W.), University of Liège, University Hospital; and Fonds National de la Recherche Scientifique (M.M.), Brussels, Belgium
| | - Massimo Pandolfo
- Department of Neurology (C.D., M.M., M.P.), Department of Medical Genetics (N.S.), Hôpital Erasme, Laboratory of Experimental Neurology (C.D., S.D., M.R., M.M.), Université Libre de Bruxelles; Department of Physical Medicine and Rehabilitation (F.C.W.), University of Liège, University Hospital; and Fonds National de la Recherche Scientifique (M.M.), Brussels, Belgium
| |
Collapse
|
71
|
Mathis S, Goizet C, Tazir M, Magy L, Vallat J. Reasons Charcot–Marie–Tooth disease due to mutations in the
MME
gene should not be named AR‐CMT2T. Ann Neurol 2016; 80:477. [DOI: 10.1002/ana.24741] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2016] [Revised: 06/21/2016] [Accepted: 06/22/2016] [Indexed: 11/06/2022]
Affiliation(s)
- Stéphane Mathis
- Department of NeurologyPoitiers University Hospital CenterPoitiers France
| | - Cyril Goizet
- Department of Medical Genetics(national reference center “Neuromuscular Diseases of the Great Southwest”), University Hospital (Pellegrin University Hospital Center), and Maladies Rares: Génétique et Métabolisme (MRGM) Laboratory, National Institute of Health and Medical Research U1211, University of BordeauxBordeaux France
| | - Meriem Tazir
- Department of NeurologyMustapha Bacha University HospitalAlgiers Algeria
| | - Laurent Magy
- Department of Neurology(National reference center “Rare Peripheral Neuropathies”), Dupuytren University HospitalLimoges France
| | - Jean‐Michel Vallat
- Department of Neurology(National reference center “Rare Peripheral Neuropathies”), Dupuytren University HospitalLimoges France
| |
Collapse
|
72
|
Drew AP, Cutrupi AN, Brewer MH, Nicholson GA, Kennerson ML. A 1.35 Mb DNA fragment is inserted into the DHMN1 locus on chromosome 7q34–q36.2. Hum Genet 2016; 135:1269-1278. [DOI: 10.1007/s00439-016-1720-4] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2016] [Accepted: 07/25/2016] [Indexed: 10/21/2022]
|