1
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Massuyama BK, Gama MTD, Silva TYT, Braga-Neto P, Pedroso JL, Barsottini OGP. Ataxias in Brazil: 17 years of experience in an ataxia center. ARQUIVOS DE NEURO-PSIQUIATRIA 2024; 82:1-8. [PMID: 38964341 DOI: 10.1055/s-0044-1787800] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/06/2024]
Abstract
BACKGROUND Cerebellar ataxias comprise sporadic and genetic etiologies. Ataxia may also be a presenting feature in hereditary spastic paraplegias (HSPs). OBJECTIVE To report a descriptive analysis of the frequency of different forms of cerebellar ataxia evaluated over 17 years in the Ataxia Unit of Universidade Federal de São Paulo, Brazil. METHODS Charts of patients who were being followed from January 2007 to December 2023 were reviewed. We used descriptive statistics to present our results as frequencies and percentages of the overall analysis. Diagnosed patients were classified according to the following 9 groups: sporadic ataxia, spinocerebellar ataxias (SCAs), other autosomal dominant cerebellar ataxias, autosomal recessive cerebellar ataxias (ARCAs), mitochondrial ataxias, congenital ataxias, X-linked ataxias, HSPs, and others. RESULTS There were 1,332 patients with ataxias or spastic paraplegias. Overall, 744 (55.85%) of all cases were successfully diagnosed: 101 sporadic ataxia, 326 SCAs, 20 of other autosomal dominant cerebellar ataxias, 186 ARCAs, 6 X-linked ataxias, 2 mitochondrial ataxias, 4 congenital ataxias, and 51 HSPs. CONCLUSION This study describes the frequency of cerebellar ataxias in a large group of patients followed for the past 17 years, of whom 55% obtained a definitive clinical or molecular diagnosis. Future demographic surveys in Brazil or Latin American remain necessary.
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Affiliation(s)
- Breno Kazuo Massuyama
- Universidade Federal de São Paulo, Escola Paulista de Medicina, Disciplina de Neurologia Clínica, Setor de Ataxias, São Paulo SP, Brazil
| | - Maria Thereza Drumond Gama
- Universidade Federal de São Paulo, Escola Paulista de Medicina, Disciplina de Neurologia Clínica, Setor de Ataxias, São Paulo SP, Brazil
| | - Thiago Yoshinaga Tonholo Silva
- Universidade Federal de São Paulo, Escola Paulista de Medicina, Disciplina de Neurologia Clínica, Setor de Ataxias, São Paulo SP, Brazil
| | - Pedro Braga-Neto
- Universidade Federal do Ceará, Faculdade de Medicina, Departamento de Clínica Médica, Fortaleza CE, Brazil
- Universidade Estadual do Ceará, Centro de Ciências da Saúde, Fortaleza CE, Brazil
| | - José Luiz Pedroso
- Universidade Federal de São Paulo, Escola Paulista de Medicina, Disciplina de Neurologia Clínica, Setor de Ataxias, São Paulo SP, Brazil
| | - Orlando Graziani Povoas Barsottini
- Universidade Federal de São Paulo, Escola Paulista de Medicina, Disciplina de Neurologia Clínica, Setor de Ataxias, São Paulo SP, Brazil
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2
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Avila-Jaque D, Martin F, Bustamante ML, Luna Álvarez M, Fernández JM, Dávila Ortiz de Montellano DJ, Pardo R, Varela D, Miranda M. The Phenotypic Spectrum of Spinocerebellar Ataxia Type 19 in a Series of Latin American Patients. CEREBELLUM (LONDON, ENGLAND) 2024; 23:1727-1732. [PMID: 38180701 DOI: 10.1007/s12311-023-01654-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 12/23/2023] [Indexed: 01/06/2024]
Abstract
Spinocerebellar ataxia 19 (SCA19) represents a rare autosomal dominant genetic disorder resulting in progressive ataxia and cerebellar atrophy. SCA19 is caused by variants in the KCND3 gene, which encodes a voltage-gated potassium channel subunit essential for cerebellar Purkinje cell function. We describe six cases from Chile and Mexico, representing the largest report on SCA19 in Latin America. These cases encompass a range of clinical presentations, highlighting the phenotypic variability within SCA19 from an early-onset, severe disease to a late-onset, slowly progressive condition with normal lifespan. While some patients present with pure ataxia, others also show cognitive impairment, dystonia, and other neurological symptoms. The correlations between specific KCND3 variants and phenotypic outcomes are complex and warrant further investigation. As the genomic landscape of spinocerebellar ataxias evolves, comprehensive genetic testing is becoming pivotal in improving diagnostic accuracy. This study contributes to a better understanding of the clinical spectrum of SCA19, laying the groundwork for further genotype-phenotype correlations and functional studies to elucidate the underlying pathophysiology.
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Affiliation(s)
| | | | - M Leonor Bustamante
- Fundación Diagnosis, Santiago, Chile
- Programa de Genética Humana, Instituto de Ciencias Biomédicas, Facultad de Medicina Universidad de Chile, Santiago, Chile
| | | | - José Manuel Fernández
- Clínica Alemana, Santiago, Chile
- Centro de Trastornos del Movimiento (CETRAM), Santiago, Chile
| | | | - Rosa Pardo
- Sección de Genética, Departamento de Medicina, Hospital Clínico de la Universidad de Chile, Santiago, Chile
| | - Diego Varela
- Programa de Fisiología y Biofísica, Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile, Santiago, Chile
- Millennium Nucleus of Ion Channels-Associated Diseases (MiNICAD), Universidad de Chile, Santiago, Chile
| | - Marcelo Miranda
- Fundación Diagnosis, Santiago, Chile.
- Clínica MEDS, Santiago, Chile.
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3
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Ibañez K, Jadhav B, Zanovello M, Gagliardi D, Clarkson C, Facchini S, Garg P, Martin-Trujillo A, Gies SJ, Deforie VG, Dalmia A, Hensman Moss DJ, Vandrovcova J, Rocca C, Moutsianas L, Marini-Bettolo C, Walker H, Turner C, Shoai M, Long JD, Fratta P, Langbehn DR, Tabrizi SJ, Caulfield MJ, Cortese A, Escott-Price V, Hardy J, Houlden H, Sharp AJ, Tucci A. Increased frequency of repeat expansion mutations across different populations. MEDRXIV : THE PREPRINT SERVER FOR HEALTH SCIENCES 2024:2023.07.03.23292162. [PMID: 37461547 PMCID: PMC10350132 DOI: 10.1101/2023.07.03.23292162] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 07/25/2023]
Abstract
Repeat expansion disorders (REDs) are a devastating group of predominantly neurological diseases. Together they are common, affecting 1 in 3,000 people worldwide with population-specific differences. However, prevalence estimates of REDs are hampered by heterogeneous clinical presentation, variable geographic distributions, and technological limitations leading to under-ascertainment. Here, leveraging whole genome sequencing data from 82,176 individuals from different populations, we found an overall disease allele frequency of REDs of 1 in 283 individuals. Modelling disease prevalence using genetic data, age at onset and survival, we show that the expected number of people with REDs would be two to three times higher than currently reported figures, indicating under-diagnosis and/or incomplete penetrance. While some REDs are population-specific, e.g. Huntington disease-like 2 in Africans, most REDs are represented in all broad genetic ancestries (i.e. Europeans, Africans, Americans, East Asians, and South Asians), challenging the notion that some REDs are found only in specific populations. These results have worldwide implications for local and global health communities in the diagnosis and counselling of REDs.
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Affiliation(s)
- Kristina Ibañez
- William Harvey Research Institute, Queen Mary University of London, London, EC1M 6BQ, UK
| | - Bharati Jadhav
- Department of Genetics and Genomic Sciences and Mindich Child Health and Development Institute, Icahn School of Medicine at Mount Sinai, New York, NY 10029
| | - Matteo Zanovello
- Department of Neuromuscular Diseases, Institute of Neurology, UCL, London, UK
| | - Delia Gagliardi
- William Harvey Research Institute, Queen Mary University of London, London, EC1M 6BQ, UK
- Department of Neuromuscular Diseases, Institute of Neurology, UCL, London, UK
| | - Christopher Clarkson
- William Harvey Research Institute, Queen Mary University of London, London, EC1M 6BQ, UK
| | - Stefano Facchini
- Department of Neuromuscular Diseases, Institute of Neurology, UCL, London, UK
- IRCCS Mondino Foundation, Pavia, Italy
| | - Paras Garg
- Department of Genetics and Genomic Sciences and Mindich Child Health and Development Institute, Icahn School of Medicine at Mount Sinai, New York, NY 10029
| | - Alejandro Martin-Trujillo
- Department of Genetics and Genomic Sciences and Mindich Child Health and Development Institute, Icahn School of Medicine at Mount Sinai, New York, NY 10029
| | - Scott J Gies
- Department of Genetics and Genomic Sciences and Mindich Child Health and Development Institute, Icahn School of Medicine at Mount Sinai, New York, NY 10029
| | | | | | - Davina J. Hensman Moss
- St George’s, University of London, London, SW17 0RE, UK
- Department of Neurodegenerative Disorders, Queen Square Institute of Neurology, UCL, London, UK
| | - Jana Vandrovcova
- Department of Neuromuscular Diseases, Institute of Neurology, UCL, London, UK
| | - Clarissa Rocca
- Department of Neuromuscular Diseases, Institute of Neurology, UCL, London, UK
| | | | - Chiara Marini-Bettolo
- The John Walton Muscular Dystrophy Research Centre, Translational and Clinical Research Institute, Newcastle University and Newcastle Hospitals NHS Foundation Trust, Newcastle upon Tyne, UK
| | - Helen Walker
- The John Walton Muscular Dystrophy Research Centre, Translational and Clinical Research Institute, Newcastle University and Newcastle Hospitals NHS Foundation Trust, Newcastle upon Tyne, UK
| | - Chris Turner
- MRC Centre for Neuromuscular Disease, National Hospital for Neurology and Neurosurgery, Queen Square, London, WC1N 3BG
| | - Maryam Shoai
- Department of Neurodegenerative Disorders, Queen Square Institute of Neurology, UCL, London, UK
| | - Jeffrey D Long
- Departments of Psychiatry and Biostatistics, The University of Iowa, Iowa City, IA 52242, USA
| | | | - Pietro Fratta
- Department of Neuromuscular Diseases, Institute of Neurology, UCL, London, UK
| | - Douglas R Langbehn
- Departments of Psychiatry and Biostatistics, The University of Iowa, Iowa City, IA 52242, USA
| | - Sarah J Tabrizi
- UK Dementia Research Institute, UCL, London, UK
- Department of Neurodegenerative Disorders, Queen Square Institute of Neurology, UCL, London, UK
- Huntington’s Disease Centre, UCL, London, UK
| | - Mark J Caulfield
- William Harvey Research Institute, Queen Mary University of London, London, EC1M 6BQ, UK
| | - Andrea Cortese
- Department of Neuromuscular Diseases, Institute of Neurology, UCL, London, UK
| | - Valentina Escott-Price
- Department of Psychological Medicine and Clinical Neuroscience, School of Medicine, Cardiff University, UK
- Dementia Research Institute, Cardiff University, UK
| | - John Hardy
- Department of Neurodegenerative Disorders, Queen Square Institute of Neurology, UCL, London, UK
| | - Henry Houlden
- Department of Neurodegenerative Disorders, Queen Square Institute of Neurology, UCL, London, UK
- Neurogenetics Unit, National Hospital for Neurology and Neurosurgery, London, UK
| | - Andrew J Sharp
- Department of Genetics and Genomic Sciences and Mindich Child Health and Development Institute, Icahn School of Medicine at Mount Sinai, New York, NY 10029
| | - Arianna Tucci
- William Harvey Research Institute, Queen Mary University of London, London, EC1M 6BQ, UK
- Department of Neuromuscular Diseases, Institute of Neurology, UCL, London, UK
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Potashman M, Popoff E, Powell L, Mackenzie A, Beiner MW, Coric V, Schmahmann J, L'Italien G. Psychometric Validation of the Modified Functional Scale for the Assessment and Rating of Ataxia (f-SARA) in Patients With Spinocerebellar Ataxia. CEREBELLUM (LONDON, ENGLAND) 2024:10.1007/s12311-024-01707-9. [PMID: 38865059 DOI: 10.1007/s12311-024-01707-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 05/27/2024] [Indexed: 06/13/2024]
Abstract
This study aimed to generate evidence to support psychometric validity of the modified functional Scale for the Assessment and Rating of Ataxia (f-SARA) among patients with spinocerebellar ataxia (SCA). Psychometric measurement properties and minimal change thresholds of the f-SARA were evaluated using data from a cohort of SCA subjects (recruited at Massachusetts General Hospital [MGH]; n = 33) and data from a phase 3 trial of troriluzole in adults with SCA (NCT03701399 [Study 206]; n = 217), including a subset of patients with the SCA3 genotype (n = 89). f-SARA item ceiling effects were absent within the MGH cohort, while floor effects were present. Excellent internal consistency reliability was demonstrated (αtotal = 0.90; αitems-removed = 0.86-0.90), and item-to-total correlations were strong (r = 0.82-0.91, per item). High test-retest reliability was demonstrated with intraclass correlation coefficients of 0.91 (total) and 0.73-0.92 (items). Convergent and divergent validity was supported, with strong correlations observed between the f-SARA and similarly constructed scales (FARS-FUNC, BARS, PROM-ADL, and FARS-ADL; all p < 0.001) and weaker correlations observed among measures of differing constructs. Mean item and total scores increased with disease severity (by FARS-FUNC quartile; p < 0.001). A 1-point threshold for meaningful changes was supported as 0.5 × SD = 0.89, SEM = 1.12, and mean changes from baseline for patients classified as "improved," "no change," or "deteriorated" were -0.68, 0.02, and 0.58, respectively. Similar trends were observed in Study 206 all-SCA and SCA3 cohorts. The measurement properties of the f-SARA provide evidence of its psychometric validity, responsiveness, and suitability as a clinical outcome measure in patients with SCA, including those with SCA3.
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Affiliation(s)
- Michele Potashman
- Biohaven Pharmaceuticals, Inc, 215 Church Street, New Haven, CT, 06510, USA.
| | - Evan Popoff
- Broadstreet Health Economics & Outcomes Research, Vancouver, BC, Canada
| | - Lauren Powell
- Broadstreet Health Economics & Outcomes Research, Vancouver, BC, Canada
| | - Ainsley Mackenzie
- Biohaven Pharmaceuticals, Inc, 215 Church Street, New Haven, CT, 06510, USA
| | | | - Vlad Coric
- Biohaven Pharmaceuticals, Inc, 215 Church Street, New Haven, CT, 06510, USA
| | - Jeremy Schmahmann
- Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA
| | - Gilbert L'Italien
- Biohaven Pharmaceuticals, Inc, 215 Church Street, New Haven, CT, 06510, USA
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5
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Rudaks LI, Yeow D, Ng K, Deveson IW, Kennerson ML, Kumar KR. An Update on the Adult-Onset Hereditary Cerebellar Ataxias: Novel Genetic Causes and New Diagnostic Approaches. CEREBELLUM (LONDON, ENGLAND) 2024:10.1007/s12311-024-01703-z. [PMID: 38760634 DOI: 10.1007/s12311-024-01703-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 05/07/2024] [Indexed: 05/19/2024]
Abstract
The hereditary cerebellar ataxias (HCAs) are rare, progressive neurologic disorders caused by variants in many different genes. Inheritance may follow autosomal dominant, autosomal recessive, X-linked or mitochondrial patterns. The list of genes associated with adult-onset cerebellar ataxia is continuously growing, with several new genes discovered in the last few years. This includes short-tandem repeat (STR) expansions in RFC1, causing cerebellar ataxia, neuropathy, vestibular areflexia syndrome (CANVAS), FGF14-GAA causing spinocerebellar ataxia type 27B (SCA27B), and THAP11. In addition, the genetic basis for SCA4, has recently been identified as a STR expansion in ZFHX3. Given the large and growing number of genes, and different gene variant types, the approach to diagnostic testing for adult-onset HCA can be complex. Testing methods include targeted evaluation of STR expansions (e.g. SCAs, Friedreich ataxia, fragile X-associated tremor/ataxia syndrome, dentatorubral-pallidoluysian atrophy), next generation sequencing for conventional variants, which may include targeted gene panels, whole exome, or whole genome sequencing, followed by various potential additional tests. This review proposes a diagnostic approach for clinical testing, highlights the challenges with current testing technologies, and discusses future advances which may overcome these limitations. Implementing long-read sequencing has the potential to transform the diagnostic approach in HCA, with the overall aim to improve the diagnostic yield.
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Affiliation(s)
- Laura Ivete Rudaks
- Molecular Medicine Laboratory and Neurology Department, Concord Repatriation General Hospital, Sydney, Australia.
- Faculty of Medicine and Health, The University of Sydney, Sydney, Australia.
- Genomics and Inherited Disease Program, The Garvan Institute of Medical Research, Sydney, Australia.
- Clinical Genetics Unit, Royal North Shore Hospital, Sydney, Australia.
| | - Dennis Yeow
- Molecular Medicine Laboratory and Neurology Department, Concord Repatriation General Hospital, Sydney, Australia
- Faculty of Medicine and Health, The University of Sydney, Sydney, Australia
- Genomics and Inherited Disease Program, The Garvan Institute of Medical Research, Sydney, Australia
- Neurodegenerative Service, Prince of Wales Hospital, Sydney, Australia
- Neuroscience Research Australia, Sydney, Australia
| | - Karl Ng
- Faculty of Medicine and Health, The University of Sydney, Sydney, Australia
- Neurology Department, Royal North Shore Hospital, Sydney, Australia
| | - Ira W Deveson
- Genomics and Inherited Disease Program, The Garvan Institute of Medical Research, Sydney, Australia
- Faculty of Medicine, University of New South Wales, Sydney, Australia
| | - Marina L Kennerson
- Molecular Medicine Laboratory and Neurology Department, Concord Repatriation General Hospital, Sydney, Australia
- Faculty of Medicine and Health, The University of Sydney, Sydney, Australia
- The Northcott Neuroscience Laboratory, ANZAC Research Institute, Sydney Local Health District, Sydney, Australia
| | - Kishore Raj Kumar
- Molecular Medicine Laboratory and Neurology Department, Concord Repatriation General Hospital, Sydney, Australia
- Faculty of Medicine and Health, The University of Sydney, Sydney, Australia
- Genomics and Inherited Disease Program, The Garvan Institute of Medical Research, Sydney, Australia
- Faculty of Medicine, University of New South Wales, Sydney, Australia
- Faculty of Medicine, St Vincent's Healthcare Campus, UNSW Sydney, Sydney, Australia
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6
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Moraes DBV, Coradine TLC, Silva EVL, Sobreira-Neto MA, Marques W, Gitaí LLG, Tumas V. Genetic Epidemiology and Clinical Characteristics of Patients with Spinocerebellar Ataxias in an Unexplored Brazilian State, Using Strategies for Resource-Limited Settings. CEREBELLUM (LONDON, ENGLAND) 2024; 23:609-619. [PMID: 37454040 DOI: 10.1007/s12311-023-01581-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 06/25/2023] [Indexed: 07/18/2023]
Abstract
Spinocerebellar ataxias (SCAs) have a worldwide average prevalence of 2.7 cases per 100,000 individuals, with significant geographic variability. This study aimed to develop resource-limited strategies to detect and characterize the frequency and genetic-clinical profile of SCAs in an unexplored population from Alagoas State, a low Human Development Index state in northeastern Brazil. Active search strategies were employed to identify individuals with a diagnosis or clinical suspicion of SCAs, and a protocol for clinical and molecular evaluation was applied in collaboration with a reference center in Neurogenetics. A total of 73 individuals with SCAs were identified, with a minimum estimated prevalence of 2.17 cases per 100,000 inhabitants. SCA3 was the most common type (75.3%), followed by SCA7 (15.1%), SCA1 (6.8%), and SCA2 (2.7%). Patients with SCA3 subphenotype 2 were the most predominant. Detailed analysis of patients with SCA3 and SCA7 revealed age at onset and clinical features congruent with other studies, with gait disturbance and reduced visual capacity in SCA7 as the main initial manifestations. The study also identified many asymptomatic individuals at risk of developing SCAs. These findings demonstrate that simple and collaborative strategies can enhance the detection capacity of rare diseases such as SCAs in resource-limited settings and that Alagoas State has a minimum estimated prevalence of SCAs similar to the world average.
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Affiliation(s)
- Débora Beserra Vilar Moraes
- Postgraduate Program, Department of Neurosciences and Behavioral Sciences, Ribeirão Preto Medical School, University of São Paulo, Campus Universitário - Rua Bernardino de Campos, 1000 - Centro, Ribeirão Preto, SP, 65470-000, Brazil
| | - Tácio Luis Cavalcante Coradine
- Graduation Course, Faculty of Medicine, Federal University of Alagoas, Campus Universitário, Avenida Lourival Melo Mota S/N, Tabuleiro dos Martins, CEP 57.072-900, Maceió, Alagoas, Brazil
| | - Everton Vieira Lopes Silva
- Graduation Course, Faculty of Medicine, Federal University of Alagoas, Campus Universitário, Avenida Lourival Melo Mota S/N, Tabuleiro dos Martins, CEP 57.072-900, Maceió, Alagoas, Brazil
| | - Manoel Alves Sobreira-Neto
- Division of Neurology, Faculty of Medicine, Federal University of Ceará, Rua Prof. Costa Mendes, 1408 - 4°, Andar, CEP: 60.430-140, Fortaleza, Brazil
| | - Wilson Marques
- Department of Neurosciences and Behavioral Sciences, Ribeirão Preto Medical School, University of São Paulo, Campus Universitário - Rua Bernardino de Campos, 1000 - Centro, Ribeirão Preto, SP, 65470-000, Brazil
| | - Lívia Leite Góes Gitaí
- Division of Neurology, Faculty of Medicine, Federal University of Alagoas, Campus Universitário, Avenida Lourival Melo Mota S/N, Tabuleiro dos Martins, CEP 57.072-900, Maceió, Alagoas, Brazil.
- , Maceió, Brazil.
| | - Vitor Tumas
- Department of Neurosciences and Behavioral Sciences, Ribeirão Preto Medical School, University of São Paulo, Campus Universitário - Rua Bernardino de Campos, 1000 - Centro, Ribeirão Preto, SP, 65470-000, Brazil.
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7
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Rahman MA, Orfali R, Dave N, Lam E, Naguib N, Nam YW, Zhang M. K Ca 2.2 (KCNN2): A physiologically and therapeutically important potassium channel. J Neurosci Res 2023; 101:1699-1710. [PMID: 37466411 PMCID: PMC10932612 DOI: 10.1002/jnr.25233] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2023] [Revised: 07/05/2023] [Accepted: 07/08/2023] [Indexed: 07/20/2023]
Abstract
One group of the K+ ion channels, the small-conductance Ca2+ -activated potassium channels (KCa 2.x, also known as SK channels family), is widely expressed in neurons as well as the heart, endothelial cells, etc. They are named small-conductance Ca2+ -activated potassium channels (SK channels) due to their comparatively low single-channel conductance of about ~10 pS. These channels are insensitive to changes in membrane potential and are activated solely by rises in the intracellular Ca2+ . According to the phylogenic research done on the KCa 2.x channels family, there are three channels' subtypes: KCa 2.1, KCa 2.2, and KCa 2.3, which are encoded by KCNN1, KCNN2, and KCNN3 genes, respectively. The KCa 2.x channels regulate neuronal excitability and responsiveness to synaptic input patterns. KCa 2.x channels inhibit excitatory postsynaptic potentials (EPSPs) in neuronal dendrites and contribute to the medium afterhyperpolarization (mAHP) that follows the action potential bursts. Multiple brain regions, including the hippocampus, express the KCa 2.2 channel encoded by the KCNN2 gene on chromosome 5. Of particular interest, rat cerebellar Purkinje cells express KCa 2.2 channels, which are crucial for various cellular processes during development and maturation. Patients with a loss-of-function of KCNN2 mutations typically exhibit extrapyramidal symptoms, cerebellar ataxia, motor and language developmental delays, and intellectual disabilities. Studies have revealed that autosomal dominant neurodevelopmental movement disorders resembling rodent symptoms are caused by heterozygous loss-of-function mutations, which are most likely to induce KCNN2 haploinsufficiency. The KCa 2.2 channel is a promising drug target for spinocerebellar ataxias (SCAs). SCAs exhibit the dysregulation of firing in cerebellar Purkinje cells which is one of the first signs of pathology. Thus, selective KCa 2.2 modulators are promising potential therapeutics for SCAs.
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Affiliation(s)
- Mohammad Asikur Rahman
- Department of Biomedical and Pharmaceutical Sciences, Chapman University School of Pharmacy, Irvine, California 92618, USA
| | - Razan Orfali
- Department of Biomedical and Pharmaceutical Sciences, Chapman University School of Pharmacy, Irvine, California 92618, USA
| | - Nikita Dave
- Department of Biomedical and Pharmaceutical Sciences, Chapman University School of Pharmacy, Irvine, California 92618, USA
| | - Elyn Lam
- Department of Biomedical and Pharmaceutical Sciences, Chapman University School of Pharmacy, Irvine, California 92618, USA
| | - Nadeen Naguib
- Department of Biomedical and Pharmaceutical Sciences, Chapman University School of Pharmacy, Irvine, California 92618, USA
| | - Young-Woo Nam
- Department of Biomedical and Pharmaceutical Sciences, Chapman University School of Pharmacy, Irvine, California 92618, USA
| | - Miao Zhang
- Department of Biomedical and Pharmaceutical Sciences, Chapman University School of Pharmacy, Irvine, California 92618, USA
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Linares AJ, Fogel BL. Late-onset hereditary ataxias with dementia. Curr Opin Neurol 2023; 36:324-334. [PMID: 37382141 PMCID: PMC10524827 DOI: 10.1097/wco.0000000000001170] [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: 06/30/2023]
Abstract
PURPOSE OF REVIEW Late-onset genetic cerebellar ataxias are clinically heterogenous with variable phenotypes. Several of these conditions are commonly associated with dementia. Recognition of the relationship between ataxia and dementia can guide clinical genetic evaluation. RECENT FINDINGS Spinocerebellar ataxias often present with variable phenotypes that may include dementia. Genomic studies have begun to identify links between incomplete penetrance and such variable phenotypes in certain hereditary ataxias. Recent studies evaluating the interaction of TBP repeat expansions and STUB1 sequence variants provide a framework to understand how genetic interactions influence disease penetrance and dementia risk in spinocerebellar ataxia types 17 and 48. Further advances in next generation sequencing methods will continue to improve diagnosis and create new insights into the expressivity of existing disorders. SUMMARY The late-onset hereditary ataxias are a clinically heterogenous group of disorders with complex presentations that can include cognitive impairment and/or dementia. Genetic evaluation of late-onset ataxia patients with dementia follows a systemic testing approach that often utilizes repeat expansion testing followed by next-generation sequencing. Advances in bioinformatics and genomics is improving both diagnostic evaluation and establishing a basis for phenotypic variability. Whole genome sequencing will likely replace exome sequencing as a more comprehensive means of routine testing.
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Affiliation(s)
- Anthony J. Linares
- Department of Neurology, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA, 90095 USA
| | - Brent L. Fogel
- Department of Neurology, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA, 90095 USA
- Department of Human Genetics, David Geffen School of Medicine, University of California Los Angeles, 90095 USA
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9
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Duggirala N, Ngo KJ, Pagnoni SM, Rosa AL, Fogel BL. Spinocerebellar ataxia type 14 (SCA14) in an Argentinian family: a case report. J Med Case Rep 2023; 17:168. [PMID: 37101238 PMCID: PMC10134643 DOI: 10.1186/s13256-023-03897-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2022] [Accepted: 03/19/2023] [Indexed: 04/28/2023] Open
Abstract
BACKGROUND Hereditary spinocerebellar ataxias are a group of genetic neurological disorders that result in degeneration of the cerebellum and brainstem, leading to difficulty in controlling balance and muscle coordination. CASE PRESENTATION A family affected by spinocerebellar ataxia was identified in Argentina and investigated using whole exome sequencing to determine the genetic etiology. The proband, a female white Hispanic aged 48, was noted to have slowly progressive gait ataxia, dysarthria, nystagmus, and moderate cerebellar atrophy. Whole exome sequencing was performed on three affected and two unaffected family members and revealed a dominant pathogenic variant, p.Gln127Arg (19:54392986 A>G), in the protein kinase C gamma gene, and the family was diagnosed with spinocerebellar ataxia type 14. CONCLUSIONS To our knowledge, no previous cases of spinocerebellar ataxia type 14 have been reported in Argentina, expanding the global presence of this neurological disorder. This diagnosis supports whole exome sequencing as a high-yield method for identifying coding variants causing cerebellar ataxias and emphasizes the importance of broadening the clinical availability of whole exome sequencing for undiagnosed patients and families.
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Affiliation(s)
- Niharika Duggirala
- Department of Neurology, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA, 90095, USA
| | - Kathie J Ngo
- Department of Neurology, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA, 90095, USA
| | - Sabrina M Pagnoni
- Laboratorio de Genética y Biología Molecular, Fundación Allende Y Sanatorio Allende, Córdoba, Argentina
- Facultad de Ciencias Químicas, IRNASUS-CONICET, Universidad Católica de Cordoba, Córdoba, Argentina
- Departamento de Farmacología, IFEC-CONICET, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Córdoba, Argentina
| | - Alberto L Rosa
- Laboratorio de Genética y Biología Molecular, Fundación Allende Y Sanatorio Allende, Córdoba, Argentina
- Facultad de Ciencias Químicas, IRNASUS-CONICET, Universidad Católica de Cordoba, Córdoba, Argentina
- Departamento de Farmacología, IFEC-CONICET, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Córdoba, Argentina
| | - Brent L Fogel
- Department of Neurology, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA, 90095, USA.
- Department of Human Genetics, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA, 90095, USA.
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10
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Alshimemeri S, Abo Alsamh D, Zhou L, Furtado S, Kraft S, Bruno V, Duquette A, Brais B, Suchowersky O, Munhoz RP, Slow E. Demographics and Clinical Characteristics of Autosomal Dominant Spinocerebellar Ataxia in Canada. Mov Disord Clin Pract 2023; 10:440-451. [PMID: 36949783 PMCID: PMC10026276 DOI: 10.1002/mdc3.13666] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2022] [Accepted: 01/02/2023] [Indexed: 01/27/2023] Open
Abstract
Background Autosomal dominant (AD) spinocerebellar ataxias (SCAs) encompass a large group of rare disorders, which occurs in individuals of different ethnic backgrounds. To date, demographics, and clinical descriptions of AD SCA in Canada are lacking. Methods A retrospective chart review of patients with a genetically confirmed diagnosis of AD SCAs was performed at five tertiary centers across Canada in the provinces of Quebec, Alberta, and Ontario. Demographic, genetic, and clinical information were collected and analyzed. Results A total of 203 patients with AD SCA were identified. Weighted estimated prevalence of AD SCA in three large Canadian provinces was calculated (2.25 cases per 100.000) which is in keeping with the figures documented worldwide. We found that the distribution of the most common SCA differed when comparing provinces. The most prevalent SCA diagnosis in Ontario was SCA3 (49%), while the most prevalent SCA diagnosis in Alberta and Quebec was SCA2 in 26% and 47%, respectively. SCA6 was the third most prevalent SCA subtype in Quebec (14%), which was not seen as commonly in other provinces. SCA1 was uncommonly seen in both Alberta and Quebec, despite being common in Ontario. Conclusions In this largest Canadian study, we describe the prevalence, distribution, and clinical characteristics of AD SCA. We found that the distribution of the most common SCA differed in the three provinces studied. This finding reflects the heterogenous nature of the Canadian population.
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Affiliation(s)
- Sohaila Alshimemeri
- King Saud UniversityRiyadhSaudi Arabia
- University of TorontoTorontoOntarioCanada
| | | | - Lily Zhou
- University of British ColumbiaVancouverBritish ColumbiaCanada
| | | | | | | | | | | | | | - Renato P. Munhoz
- University of TorontoTorontoOntarioCanada
- University Health NetworkTorontoOntarioCanada
| | - Elizabeth Slow
- University of TorontoTorontoOntarioCanada
- University Health NetworkTorontoOntarioCanada
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11
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Lopes da Cunha P, Fittipaldi S, González Campo C, Kauffman M, Rodríguez-Quiroga S, Yacovino DA, Ibáñez A, Birba A, García AM. Social concepts and the cerebellum: behavioural and functional connectivity signatures in cerebellar ataxic patients. Philos Trans R Soc Lond B Biol Sci 2023; 378:20210364. [PMID: 36571119 PMCID: PMC9791482 DOI: 10.1098/rstb.2021.0364] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2021] [Accepted: 09/26/2022] [Indexed: 12/27/2022] Open
Abstract
Neurocognitive research on social concepts underscores their reliance on fronto-temporo-limbic regions mediating broad socio-cognitive skills. Yet, the field has neglected another structure increasingly implicated in social cognition: the cerebellum. The present exploratory study examines this link combining a novel naturalistic text paradigm, a relevant atrophy model and functional magnetic resonance imaging. Fifteen cerebellar ataxia (CA) patients with focal cerebellar atrophy and 29 matched controls listened to a social text (highlighting interpersonal events) as well as a non-social text (focused on a single person's actions), and answered comprehension questionnaires. We compared behavioural outcomes between groups and examined their association with cerebellar connectivity. CA patients showed deficits in social text comprehension and normal scores in the non-social text. Also, social text outcomes in controls selectively correlated with connectivity between the cerebellum and key regions subserving multi-modal semantics and social cognition, including the superior and medial temporal gyri, the temporal pole and the insula. Conversely, brain-behaviour associations involving the cerebellum were abolished in the patients. Thus, cerebellar structures and connections seem involved in processing social concepts evoked by naturalistic discourse. Such findings invite new theoretical and translational developments integrating social neuroscience with embodied semantics. This article is part of the theme issue 'Concepts in interaction: social engagement and inner experiences'.
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Affiliation(s)
- Pamela Lopes da Cunha
- Cognitive Neuroscience Center, University of San Andrés, Buenos Aires B1644BID, Argentina
- National Agency for Scientific Promotion and Technology (ANPCyT), Buenos Aires, C1425FQD, Argentina
| | - Sol Fittipaldi
- Cognitive Neuroscience Center, University of San Andrés, Buenos Aires B1644BID, Argentina
- National Scientific and Technical Research Council (CONICET), Buenos Aires, C1425FQB, Argentina
- Global Brain Health Institute, University of California San Francisco, 94158-2324, US and Trinity College Dublin, D02 PN40, Ireland
- Latin American Brain Health Institute (BrainLat), Adolfo Ibáñez University, Santiago, 7550344, Chile
| | - Cecilia González Campo
- Cognitive Neuroscience Center, University of San Andrés, Buenos Aires B1644BID, Argentina
- National Scientific and Technical Research Council (CONICET), Buenos Aires, C1425FQB, Argentina
| | - Marcelo Kauffman
- Consultorio y Laboratorio de Neurogenética, Centro Universitario de Neurología “José María Ramos Mejía” y División Neurología, Hospital JM Ramos Mejía, Facultad de Medicina, UBA, Buenos Aires, C1221ADC, Argentina
- School of Medicine, UBA, CONICET, Buenos Aires, C1121ABG, Argentina
| | - Sergio Rodríguez-Quiroga
- Consultorio y Laboratorio de Neurogenética, Centro Universitario de Neurología “José María Ramos Mejía” y División Neurología, Hospital JM Ramos Mejía, Facultad de Medicina, UBA, Buenos Aires, C1221ADC, Argentina
| | - Darío Andrés Yacovino
- Department of Neurology, Dr. Cesar Milstein Hospital, Buenos Aires, C1221ACI, Argentina
- Memory and Balance Clinic, Buenos Aires, C1425BPC, Argentina
| | - Agustín Ibáñez
- Cognitive Neuroscience Center, University of San Andrés, Buenos Aires B1644BID, Argentina
- National Scientific and Technical Research Council (CONICET), Buenos Aires, C1425FQB, Argentina
- Global Brain Health Institute, University of California San Francisco, 94158-2324, US and Trinity College Dublin, D02 PN40, Ireland
- Latin American Brain Health Institute (BrainLat), Adolfo Ibáñez University, Santiago, 7550344, Chile
| | - Agustina Birba
- Cognitive Neuroscience Center, University of San Andrés, Buenos Aires B1644BID, Argentina
- National Scientific and Technical Research Council (CONICET), Buenos Aires, C1425FQB, Argentina
| | - Adolfo M. García
- Cognitive Neuroscience Center, University of San Andrés, Buenos Aires B1644BID, Argentina
- National Scientific and Technical Research Council (CONICET), Buenos Aires, C1425FQB, Argentina
- Global Brain Health Institute, University of California San Francisco, 94158-2324, US and Trinity College Dublin, D02 PN40, Ireland
- Departamento de Lingüística y Literatura, Facultad de Humanidades, Universidad de Santiago de Chile, Santiago, 9170022, Chile
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12
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Spinocerebellar ataxia in a cohort of patients from Rio de Janeiro. Neurol Sci 2022; 43:4997-5005. [DOI: 10.1007/s10072-022-06084-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2022] [Accepted: 04/14/2022] [Indexed: 10/18/2022]
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13
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Zotin MCZ. Keeping our balance in cerebellar ataxia: the contribution of neuroimaging to clinical investigation. Radiol Bras 2022; 55:VII-VIII. [PMID: 36320368 PMCID: PMC9620850 DOI: 10.1590/0100-3984.2022.55.5e2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/03/2022] Open
Affiliation(s)
- Maria Clara Zanon Zotin
- Center for Imaging Sciences and Medical Physics, Department of
Medical Imaging, Hematology, and Clinical Oncology, Faculdade de Medicina de
Ribeirão Preto da Universidade de São Paulo (FMRP-USP),
Ribeirão Preto, SP, Brazil. , Philip Kistler Stroke Research Center, Department of Neurology,
Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
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14
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van Prooije T, Ibrahim NM, Azmin S, van de Warrenburg B. Spinocerebellar ataxias in Asia: Prevalence, phenotypes and management. Parkinsonism Relat Disord 2021; 92:112-118. [PMID: 34711523 DOI: 10.1016/j.parkreldis.2021.10.023] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/27/2021] [Revised: 10/05/2021] [Accepted: 10/19/2021] [Indexed: 11/19/2022]
Abstract
This paper reviews and summarizes three main aspects of spinocerebellar ataxias (SCA) in the Asian population. First, epidemiological studies were comprehensively reviewed. Overall, the most common subtypes include SCA1, SCA2, SCA3, and SCA6, but there are large differences in the relative prevalence of these and other SCA subtypes between Asian countries. Some subtypes such as SCA12 and SCA31 are rather specific to certain Asian populations. Second, we summarized distinctive phenotypic manifestations of SCA patients of Asian origin, for example a frequent co-occurrence of parkinsonism in some SCA subtypes. Lastly, we have conducted an exploratory survey study to map SCA-specific expertise, resources, and management in various Asian countries. This showed large differences in accessibility, genetic testing facilities, and treatment options between lower and higher income Asian countries. Currently, many Asian SCA patients remain without a final genetic diagnosis. Lack of prevalence data on SCA, lack of patient registries, and insufficient access to genetic testing facilities hamper a wider understanding of these diseases in several (particularly lower income) Asian countries.
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Affiliation(s)
- Teije van Prooije
- Department of Neurology, Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center, 6500 HB, Nijmegen, the Netherlands
| | - Norlinah Mohamed Ibrahim
- Neurology Unit, Department of Medicine, Universiti Kebangsaan Malaysia Medical Centre, Kuala Lumpur, Malaysia
| | - Shahrul Azmin
- Neurology Unit, Department of Medicine, Universiti Kebangsaan Malaysia Medical Centre, Kuala Lumpur, Malaysia
| | - Bart van de Warrenburg
- Department of Neurology, Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center, 6500 HB, Nijmegen, the Netherlands.
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15
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Hommersom MP, Buijsen RAM, van Roon-Mom WMC, van de Warrenburg BPC, van Bokhoven H. Human Induced Pluripotent Stem Cell-Based Modelling of Spinocerebellar Ataxias. Stem Cell Rev Rep 2021; 18:441-456. [PMID: 34031815 PMCID: PMC8930896 DOI: 10.1007/s12015-021-10184-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/11/2021] [Indexed: 12/13/2022]
Abstract
Abstract Dominant spinocerebellar ataxias (SCAs) constitute a large group of phenotypically and genetically heterogeneous disorders that mainly present with dysfunction of the cerebellum as their main hallmark. Although animal and cell models have been highly instrumental for our current insight into the underlying disease mechanisms of these neurodegenerative disorders, they do not offer the full human genetic and physiological context. The advent of human induced pluripotent stem cells (hiPSCs) and protocols to differentiate these into essentially every cell type allows us to closely model SCAs in a human context. In this review, we systematically summarize recent findings from studies using hiPSC-based modelling of SCAs, and discuss what knowledge has been gained from these studies. We conclude that hiPSC-based models are a powerful tool for modelling SCAs as they contributed to new mechanistic insights and have the potential to serve the development of genetic therapies. However, the use of standardized methods and multiple clones of isogenic lines are essential to increase validity and reproducibility of the insights gained. Graphical Abstract ![]()
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Affiliation(s)
- Marina P Hommersom
- Department of Human Genetics, Donders Institute for Brain, Cognition, and Behaviour, Radboud University Medical Center, 6500 HB, Nijmegen, The Netherlands
| | - Ronald A M Buijsen
- Department of Human Genetics, Leiden University Medical Center, 2300 RC, Leiden, The Netherlands
| | - Willeke M C van Roon-Mom
- Department of Human Genetics, Leiden University Medical Center, 2300 RC, Leiden, The Netherlands
| | - Bart P C van de Warrenburg
- Department of Neurology, Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center, 6500 HB, Nijmegen, The Netherlands.
| | - Hans van Bokhoven
- Department of Human Genetics, Donders Institute for Brain, Cognition, and Behaviour, Radboud University Medical Center, 6500 HB, Nijmegen, The Netherlands. .,Department of Cognitive Neuroscience, Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center, 6500 HB, Nijmegen, Netherlands.
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16
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Filling a Knowledge Gap: Prevalence of Ataxia and Spastic Paraplegia in Eastern Quebec. Can J Neurol Sci 2021; 48:601-602. [PMID: 33504375 DOI: 10.1017/cjn.2021.15] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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17
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Perez Maturo J, Zavala L, Vega P, González-Morón D, Medina N, Salinas V, Rosales J, Córdoba M, Arakaki T, Garretto N, Rodríguez-Quiroga S, Kauffman MA. Overwhelming genetic heterogeneity and exhausting molecular diagnostic process in chronic and progressive ataxias: facing it up with an algorithm, a gene, a panel at a time. J Hum Genet 2020; 65:895-902. [DOI: 10.1038/s10038-020-0785-z] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2020] [Revised: 05/19/2020] [Accepted: 05/20/2020] [Indexed: 12/18/2022]
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18
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Teive HAG, Camargo CHF, Munhoz RP. Reply to Comment on: The Geographic Diversity of Spinocerebellar Ataxias (SCAs) in the Americas. Mov Disord Clin Pract 2020; 7:347. [PMID: 32258241 PMCID: PMC7111575 DOI: 10.1002/mdc3.12909] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2020] [Accepted: 02/02/2020] [Indexed: 11/09/2022] Open
Affiliation(s)
- Hélio A. G. Teive
- Movement Disorders Unit–Neurology Service and Internal Medicine Post‐Graduation Program, Internal Medicine Department, Hospital de ClínicasFederal University of ParanáCuritibaPRBrazil
| | - Carlos Henrique F. Camargo
- Movement Disorders Unit–Neurology Service and Internal Medicine Post‐Graduation Program, Internal Medicine Department, Hospital de ClínicasFederal University of ParanáCuritibaPRBrazil
| | - Renato P. Munhoz
- Morton and Gloria Shulman Movement Disorders Centre and the Edmond J. Safra Program in Parkinson's Disease, Toronto Western Hospital, Division of NeurologyUniversity of TorontoTorontoOntarioCanada
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19
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Guarnaschelli M, Rossi M, Zajd A, Igarreta P. Comment on: The Geographic Diversity of Spinocerebellar Ataxias (SCAs) in the Americas. Mov Disord Clin Pract 2020; 7:346. [PMID: 32258240 DOI: 10.1002/mdc3.12910] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2020] [Accepted: 01/22/2020] [Indexed: 01/21/2023] Open
Affiliation(s)
- Marlen Guarnaschelli
- Movement Disorders Section, Neuroscience Department Raul Carrea Institute for Neurological Research (FLENI) Buenos Aires Argentina
| | - Malco Rossi
- Movement Disorders Section, Neuroscience Department Raul Carrea Institute for Neurological Research (FLENI) Buenos Aires Argentina.,Argentine National Scientific and Technological Research Council (CONICET) Buenos Aires Argentina
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20
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Teive HAG, Camargo CHF, Munhoz RP. Reply to Comment on: "The Geographic Diversity of Spinocerebellar Ataxias (SCAs) in the Americas: A Systematic Review". Mov Disord Clin Pract 2020; 7:239. [PMID: 32071950 PMCID: PMC7011827 DOI: 10.1002/mdc3.12877] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2019] [Accepted: 11/15/2019] [Indexed: 11/05/2022] Open
Affiliation(s)
- Hélio A. G. Teive
- Movement Disorders Unit, Neurology Service, Internal Medicine Department, and Internal Medicine Post‐Graduation Program, Hospital de ClínicasFederal University of ParanáCuritibaParanáBrazil
| | - Carlos Henrique F. Camargo
- Movement Disorders Unit, Neurology Service, Internal Medicine Department, and Internal Medicine Post‐Graduation Program, Hospital de ClínicasFederal University of ParanáCuritibaParanáBrazil
| | - Renato P. Munhoz
- Morton and Gloria Shulman Movement Disorders Centre and the Edmond J. Safra Program in Parkinson's Disease, Torotno Western Hospital, Division of NeuroogyUniversity of TorontoOntarioTorontoCanada
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21
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Hanna Al-Shaikh R, Wszolek ZK. Comment on: "The Geographic Diversity of Spinocerebellar Ataxias (SCAs) in the Americas: A Systematic Review". Mov Disord Clin Pract 2020; 7:237-238. [PMID: 32071949 DOI: 10.1002/mdc3.12878] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2019] [Accepted: 11/13/2019] [Indexed: 12/21/2022] Open
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