1
|
Rajan-Babu IS, Dolzhenko E, Eberle MA, Friedman JM. Sequence composition changes in short tandem repeats: heterogeneity, detection, mechanisms and clinical implications. Nat Rev Genet 2024; 25:476-499. [PMID: 38467784 DOI: 10.1038/s41576-024-00696-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/19/2024] [Indexed: 03/13/2024]
Abstract
Short tandem repeats (STRs) are a class of repetitive elements, composed of tandem arrays of 1-6 base pair sequence motifs, that comprise a substantial fraction of the human genome. STR expansions can cause a wide range of neurological and neuromuscular conditions, known as repeat expansion disorders, whose age of onset, severity, penetrance and/or clinical phenotype are influenced by the length of the repeats and their sequence composition. The presence of non-canonical motifs, depending on the type, frequency and position within the repeat tract, can alter clinical outcomes by modifying somatic and intergenerational repeat stability, gene expression and mutant transcript-mediated and/or protein-mediated toxicities. Here, we review the diverse structural conformations of repeat expansions, technological advances for the characterization of changes in sequence composition, their clinical correlations and the impact on disease mechanisms.
Collapse
Affiliation(s)
- Indhu-Shree Rajan-Babu
- Department of Medical Genetics, The University of British Columbia, and Children's & Women's Hospital, Vancouver, British Columbia, Canada.
| | | | | | - Jan M Friedman
- Department of Medical Genetics, The University of British Columbia, and Children's & Women's Hospital, Vancouver, British Columbia, Canada
- BC Children's Hospital Research Institute, Vancouver, British Columbia, Canada
| |
Collapse
|
2
|
Jiraanont P, Zafarullah M, Sulaiman N, Espinal GM, Randol JL, Durbin-Johnson B, Schneider A, Hagerman RJ, Hagerman PJ, Tassone F. FMR1 Protein Expression Correlates with Intelligence Quotient in Both Peripheral Blood Mononuclear Cells and Fibroblasts from Individuals with an FMR1 Mutation. J Mol Diagn 2024; 26:498-509. [PMID: 38522837 DOI: 10.1016/j.jmoldx.2024.02.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2023] [Revised: 02/15/2024] [Accepted: 02/23/2024] [Indexed: 03/26/2024] Open
Abstract
Fragile X syndrome (FXS) is the most common heritable form of intellectual disability and is caused by CGG repeat expansions exceeding 200 (full mutation). Such expansions lead to hypermethylation and transcriptional silencing of the fragile X messenger ribonucleoprotein 1 (FMR1) gene. As a consequence, little or no FMR1 protein (FMRP) is produced; absence of the protein, which normally is responsible for neuronal development and maintenance, causes the syndrome. Previous studies have demonstrated the causal relationship between FMRP levels and cognitive abilities in peripheral blood mononuclear cells (PBMCs) and dermal fibroblast cell lines of patients with FXS. However, it is arguable whether PBMCs or fibroblasts would be the preferred surrogate for measuring molecular markers, particularly FMRP, to represent the cognitive impairment, a core symptom of FXS. To address this concern, CGG repeats, methylation status, FMR1 mRNA, and FMRP levels were measured in both PBMCs and fibroblasts derived from 66 individuals. The findings indicated a strong association between FMR1 mRNA expression levels and CGG repeat numbers in PBMCs of premutation males after correcting for methylation status. Moreover, FMRP expression levels from both PBMCs and fibroblasts of male participants with a hypermethylated full mutation and with mosaicism demonstrated significant association between the intelligence quotient levels and FMRP levels, suggesting that PBMCs may be preferable for FXS clinical studies, because of their greater accessibility.
Collapse
Affiliation(s)
- Poonnada Jiraanont
- Division of Molecular and Cellular Medicine, Faculty of Medicine, King Mongkut's Institute of Technology Ladkrabang, Bangkok, Thailand
| | - Marwa Zafarullah
- Department of Biochemistry and Molecular Medicine, University of California, Davis, School of Medicine, Davis, California
| | - Noor Sulaiman
- Department of Biochemistry and Molecular Medicine, University of California, Davis, School of Medicine, Davis, California
| | - Glenda M Espinal
- Department of Biochemistry and Molecular Medicine, University of California, Davis, School of Medicine, Davis, California
| | - Jamie L Randol
- Department of Biochemistry and Molecular Medicine, University of California, Davis, School of Medicine, Davis, California
| | - Blythe Durbin-Johnson
- Division of Biostatistics, University of California, Davis, School of Medicine, Davis, California
| | - Andrea Schneider
- Department of Pediatrics, University of California, Davis, School of Medicine, Davis, California; UC Davis MIND Institute, University of California, Davis, Sacramento, California
| | - Randi J Hagerman
- Department of Pediatrics, University of California, Davis, School of Medicine, Davis, California; UC Davis MIND Institute, University of California, Davis, Sacramento, California
| | - Paul J Hagerman
- Department of Biochemistry and Molecular Medicine, University of California, Davis, School of Medicine, Davis, California; UC Davis MIND Institute, University of California, Davis, Sacramento, California
| | - Flora Tassone
- Department of Biochemistry and Molecular Medicine, University of California, Davis, School of Medicine, Davis, California; UC Davis MIND Institute, University of California, Davis, Sacramento, California.
| |
Collapse
|
3
|
Sanchez-Flores M, Corral-Juan M, Gasch-Navalón E, Cirillo D, Sanchez I, Matilla-Dueñas A. Novel genotype-phenotype correlations, differential cerebellar allele-specific methylation, and a common origin of the (ATTTC) n insertion in spinocerebellar ataxia type 37. Hum Genet 2024; 143:211-232. [PMID: 38396267 PMCID: PMC11043136 DOI: 10.1007/s00439-024-02644-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2023] [Accepted: 01/17/2024] [Indexed: 02/25/2024]
Abstract
Spinocerebellar ataxia subtype 37 (SCA37) is a rare disease originally identified in ataxia patients from the Iberian Peninsula with a pure cerebellar syndrome. SCA37 patients carry a pathogenic intronic (ATTTC)n repeat insertion flanked by two polymorphic (ATTTT)n repeats in the Disabled-1 (DAB1) gene leading to cerebellar dysregulation. Herein, we determine the precise configuration of the pathogenic 5'(ATTTT)n-(ATTTC)n-3'(ATTTT)n SCA37 alleles by CRISPR-Cas9 and long-read nanopore sequencing, reveal their epigenomic signatures in SCA37 lymphocytes, fibroblasts, and cerebellar samples, and establish new molecular and clinical correlations. The 5'(ATTTT)n-(ATTTC)n-3'(ATTTT)n pathogenic allele configurations revealed repeat instability and differential methylation signatures. Disease age of onset negatively correlated with the (ATTTC)n, and positively correlated with the 3'(ATTTT)n. Geographic origin and gender significantly correlated with age of onset. Furthermore, significant predictive regression models were obtained by machine learning for age of onset and disease evolution by considering gender, the (ATTTC)n, the 3'(ATTTT)n, and seven CpG positions differentially methylated in SCA37 cerebellum. A common 964-kb genomic region spanning the (ATTTC)n insertion was identified in all SCA37 patients analysed from Portugal and Spain, evidencing a common origin of the SCA37 mutation in the Iberian Peninsula originating 859 years ago (95% CI 647-1378). In conclusion, we demonstrate an accurate determination of the size and configuration of the regulatory 5'(ATTTT)n-(ATTTC)n-3'(ATTTT)n repeat tract, avoiding PCR bias amplification using CRISPR/Cas9-enrichment and nanopore long-read sequencing, resulting relevant for accurate genetic diagnosis of SCA37. Moreover, we determine novel significant genotype-phenotype correlations in SCA37 and identify differential cerebellar allele-specific methylation signatures that may underlie DAB1 pathogenic dysregulation.
Collapse
Affiliation(s)
- Marina Sanchez-Flores
- Neurogenetics Unit, Department of Neuroscience, Germans Trias i Pujol Research Institute (IGTP), Universitat Autònoma de Barcelona-Can Ruti Campus, Carretera de Can Ruti, Camí de les Escoles s/n, 08916, Badalona, Spain
| | - Marc Corral-Juan
- Neurogenetics Unit, Department of Neuroscience, Germans Trias i Pujol Research Institute (IGTP), Universitat Autònoma de Barcelona-Can Ruti Campus, Carretera de Can Ruti, Camí de les Escoles s/n, 08916, Badalona, Spain
| | - Esther Gasch-Navalón
- Neurogenetics Unit, Department of Neuroscience, Germans Trias i Pujol Research Institute (IGTP), Universitat Autònoma de Barcelona-Can Ruti Campus, Carretera de Can Ruti, Camí de les Escoles s/n, 08916, Badalona, Spain
| | | | - Ivelisse Sanchez
- Neurogenetics Unit, Department of Neuroscience, Germans Trias i Pujol Research Institute (IGTP), Universitat Autònoma de Barcelona-Can Ruti Campus, Carretera de Can Ruti, Camí de les Escoles s/n, 08916, Badalona, Spain
| | - Antoni Matilla-Dueñas
- Neurogenetics Unit, Department of Neuroscience, Germans Trias i Pujol Research Institute (IGTP), Universitat Autònoma de Barcelona-Can Ruti Campus, Carretera de Can Ruti, Camí de les Escoles s/n, 08916, Badalona, Spain.
| |
Collapse
|
4
|
Kumar M, Tyagi N, Faruq M. The molecular mechanisms of spinocerebellar ataxias for DNA repeat expansion in disease. Emerg Top Life Sci 2023; 7:289-312. [PMID: 37668011 DOI: 10.1042/etls20230013] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2023] [Revised: 08/01/2023] [Accepted: 08/16/2023] [Indexed: 09/06/2023]
Abstract
Spinocerebellar ataxias (SCAs) are a heterogenous group of neurodegenerative disorders which commonly inherited in an autosomal dominant manner. They cause muscle incoordination due to degeneration of the cerebellum and other parts of nervous system. Out of all the characterized (>50) SCAs, 14 SCAs are caused due to microsatellite repeat expansion mutations. Repeat expansions can result in toxic protein gain-of-function, protein loss-of-function, and/or RNA gain-of-function effects. The location and the nature of mutation modulate the underlying disease pathophysiology resulting in varying disease manifestations. Potential toxic effects of these mutations likely affect key major cellular processes such as transcriptional regulation, mitochondrial functioning, ion channel dysfunction and synaptic transmission. Involvement of several common pathways suggests interlinked function of genes implicated in the disease pathogenesis. A better understanding of the shared and distinct molecular pathogenic mechanisms in these diseases is required to develop targeted therapeutic tools and interventions for disease management. The prime focus of this review is to elaborate on how expanded 'CAG' repeats contribute to the common modes of neurotoxicity and their possible therapeutic targets in management of such devastating disorders.
Collapse
Affiliation(s)
- Manish Kumar
- CSIR-Institute of Genomics and Integrative Biology, Mall Road, Delhi 110007, India
| | - Nishu Tyagi
- CSIR-Institute of Genomics and Integrative Biology, Mall Road, Delhi 110007, India
| | - Mohammed Faruq
- CSIR-Institute of Genomics and Integrative Biology, Mall Road, Delhi 110007, India
| |
Collapse
|
5
|
Coarelli G, Coutelier M, Durr A. Autosomal dominant cerebellar ataxias: new genes and progress towards treatments. Lancet Neurol 2023; 22:735-749. [PMID: 37479376 DOI: 10.1016/s1474-4422(23)00068-6] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2022] [Revised: 01/07/2023] [Accepted: 02/22/2023] [Indexed: 07/23/2023]
Abstract
Dominantly inherited spinocerebellar ataxias (SCAs) are associated with phenotypes that range from pure cerebellar to multisystemic. The list of implicated genes has lengthened in the past 5 years with the inclusion of SCA37/DAB1, SCA45/FAT2, SCA46/PLD3, SCA47/PUM1, SCA48/STUB1, SCA50/NPTX1, SCA25/PNPT1, SCA49/SAM9DL, and SCA27B/FGF14. In some patients, co-occurrence of multiple potentially pathogenic variants can explain variable penetrance or more severe phenotypes. Given this extreme clinical and genetic heterogeneity, genome sequencing should become the diagnostic tool of choice but is still not available in many clinical settings. Treatments tested in phase 2 and phase 3 studies, such as riluzole and transcranial direct current stimulation of the cerebellum and spinal cord, have given conflicting results. To enable early intervention, preataxic carriers of pathogenic variants should be assessed with biomarkers, such as neurofilament light chain and brain MRI; these biomarkers could also be used as outcome measures, given that clinical outcomes are not useful in the preataxic phase. The development of bioassays measuring the concentration of the mutant protein (eg, ataxin-3) might facilitate monitoring of target engagement by gene therapies.
Collapse
Affiliation(s)
- Giulia Coarelli
- Sorbonne Université, ICM Institut du Cerveau, Pitié-Salpeêtrieère University Hospital, Paris, France; Institut National de la Santé Et de la Recherche Médicale, Paris, France; Centre National de la Recherche Scientifique, Paris, France; Assistance Publique-Hôpitaux de Paris, Paris, France
| | - Marie Coutelier
- Sorbonne Université, ICM Institut du Cerveau, Pitié-Salpeêtrieère University Hospital, Paris, France; Institut National de la Santé Et de la Recherche Médicale, Paris, France; Centre National de la Recherche Scientifique, Paris, France; Assistance Publique-Hôpitaux de Paris, Paris, France
| | - Alexandra Durr
- Sorbonne Université, ICM Institut du Cerveau, Pitié-Salpeêtrieère University Hospital, Paris, France; Institut National de la Santé Et de la Recherche Médicale, Paris, France; Centre National de la Recherche Scientifique, Paris, France; Assistance Publique-Hôpitaux de Paris, Paris, France.
| |
Collapse
|
6
|
Kerkhof LMC, van de Warrenburg BPC, van Roon-Mom WMC, Buijsen RAM. Therapeutic Strategies for Spinocerebellar Ataxia Type 1. Biomolecules 2023; 13:biom13050788. [PMID: 37238658 DOI: 10.3390/biom13050788] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2023] [Revised: 04/28/2023] [Accepted: 04/29/2023] [Indexed: 05/28/2023] Open
Abstract
Spinocerebellar ataxia type 1 (SCA1) is an autosomal dominant neurodegenerative disorder that affects one or two individuals per 100,000. The disease is caused by an extended CAG repeat in exon 8 of the ATXN1 gene and is characterized mostly by a profound loss of cerebellar Purkinje cells, leading to disturbances in coordination, balance, and gait. At present, no curative treatment is available for SCA1. However, increasing knowledge on the cellular and molecular mechanisms of SCA1 has led the way towards several therapeutic strategies that can potentially slow disease progression. SCA1 therapeutics can be classified as genetic, pharmacological, and cell replacement therapies. These different therapeutic strategies target either the (mutant) ATXN1 RNA or the ataxin-1 protein, pathways that play an important role in downstream SCA1 disease mechanisms or which help restore cells that are lost due to SCA1 pathology. In this review, we will provide a summary of the different therapeutic strategies that are currently being investigated for SCA1.
Collapse
Affiliation(s)
- Laurie M C Kerkhof
- Department of Human Genetics, Leiden University Medical Center, 2333 ZA Leiden, The Netherlands
- Dutch Center for RNA Therapeutics, Leiden University Medical Center, 2333 ZA Leiden, The Netherlands
| | - Bart P C van de Warrenburg
- Department of Neurology, Donders Institute for Brain, Cognition, and Behaviour, Radboud University Medical Center, 6525 GA Nijmegen, The Netherlands
| | - Willeke M C van Roon-Mom
- Department of Human Genetics, Leiden University Medical Center, 2333 ZA Leiden, The Netherlands
- Dutch Center for RNA Therapeutics, Leiden University Medical Center, 2333 ZA Leiden, The Netherlands
| | - Ronald A M Buijsen
- Department of Human Genetics, Leiden University Medical Center, 2333 ZA Leiden, The Netherlands
| |
Collapse
|
7
|
Malekshoar M, Azimi SA, Kaki A, Mousazadeh L, Motaei J, Vatankhah M. CRISPR-Cas9 Targeted Enrichment and Next-Generation Sequencing for Mutation Detection. J Mol Diagn 2023; 25:249-262. [PMID: 36841425 DOI: 10.1016/j.jmoldx.2023.01.010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2022] [Revised: 01/08/2023] [Accepted: 01/27/2023] [Indexed: 02/27/2023] Open
Abstract
Despite the rapid application of next-generation sequencing (NGS) technologies, target sequencing in regions of the genome is often required to diagnose many genetic diseases. Target enrichment can be an effective factor in reducing the cost of sequencing and the duration of sequencing. Recently, several clustered system regularly interspaced short palindromic repeats (CRISPR)-based methods (amplification-free sequencing) have been developed to target enrichment in combination with one of the NGS platforms. CRISPR-based target enrichment strategies act as an auxiliary tool to improve NGS analytical performance, thereby indirectly facilitating nucleic acid detection. The direct DNA cleavage approach by CRISPR-Cas at genome-specific sites enhances the possibility of separating native large fragments from disease-related genomic regions. The CRISPR-Cas can isolate the target region without any amplification; subsequently, long-read sequencing technologies were also implemented. These methods, as promising tools, have the ability to assess genetic and epigenetic composition for clinical application and treatment responses in cancer precision medicine. By modifying CRISPR-based enrichment protocols, it was possible to identify different types of mutations, including structural variants, short tandem repeats, fusion genes, and mobile elements. The Cas9 can specifically eliminate wild-type sequences, and it also enables the enrichment and detection of small amounts of tumor DNA fragments among the highly heterogeneous fragments of wild-type DNA.
Collapse
Affiliation(s)
- Mehrdad Malekshoar
- Anesthesiology, Critical Care and Pain Management Research Center, Hormozgan University of Medical Sciences, Bandar Abbas, Iran
| | - Sajad Ataei Azimi
- Department of Hematology-Oncology, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Arastoo Kaki
- Department of Medical Genetics, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran
| | - Leila Mousazadeh
- Department of Medical Biotechnology, School of Advanced Medical Sciences, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Jamshid Motaei
- Department of Medical Genetics, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran.
| | - Majid Vatankhah
- Anesthesiology, Critical Care and Pain Management Research Center, Hormozgan University of Medical Sciences, Bandar Abbas, Iran.
| |
Collapse
|
8
|
CNS Delivery of Nucleic Acid Therapeutics: Beyond the Blood-Brain Barrier and Towards Specific Cellular Targeting. Pharm Res 2023; 40:77-105. [PMID: 36380168 DOI: 10.1007/s11095-022-03433-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2022] [Accepted: 11/03/2022] [Indexed: 11/16/2022]
Abstract
Nucleic acid-based therapeutic molecules including small interfering RNA (siRNA), microRNA(miRNA), antisense oligonucleotides (ASOs), messenger RNA (mRNA), and DNA-based gene therapy have tremendous potential for treating diseases in the central nervous system (CNS). However, achieving clinically meaningful delivery to the brain and particularly to target cells and sub-cellular compartments is typically very challenging. Mediating cell-specific delivery in the CNS would be a crucial advance that mitigates off-target effects and toxicities. In this review, we describe these challenges and provide contemporary evidence of advances in cellular and sub-cellular delivery using a variety of delivery mechanisms and alternative routes of administration, including the nose-to-brain approach. Strategies to achieve subcellular localization, endosomal escape, cytosolic bioavailability, and nuclear transfer are also discussed. Ultimately, there are still many challenges to translating these experimental strategies into effective and clinically viable approaches for treating patients.
Collapse
|
9
|
Taylor A, Barros D, Gobet N, Schuepbach T, McAllister B, Aeschbach L, Randall E, Trofimenko E, Heuchan E, Barszcz P, Ciosi M, Morgan J, Hafford-Tear N, Davidson A, Massey T, Monckton D, Jones L, network REGISTRYH, Xenarios I, Dion V. Repeat Detector: versatile sizing of expanded tandem repeats and identification of interrupted alleles from targeted DNA sequencing. NAR Genom Bioinform 2022; 4:lqac089. [PMID: 36478959 PMCID: PMC9719798 DOI: 10.1093/nargab/lqac089] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2022] [Revised: 10/25/2022] [Accepted: 11/08/2022] [Indexed: 12/07/2022] Open
Abstract
Targeted DNA sequencing approaches will improve how the size of short tandem repeats is measured for diagnostic tests and preclinical studies. The expansion of these sequences causes dozens of disorders, with longer tracts generally leading to a more severe disease. Interrupted alleles are sometimes present within repeats and can alter disease manifestation. Determining repeat size mosaicism and identifying interruptions in targeted sequencing datasets remains a major challenge. This is in part because standard alignment tools are ill-suited for repetitive and unstable sequences. To address this, we have developed Repeat Detector (RD), a deterministic profile weighting algorithm for counting repeats in targeted sequencing data. We tested RD using blood-derived DNA samples from Huntington's disease and Fuchs endothelial corneal dystrophy patients sequenced using either Illumina MiSeq or Pacific Biosciences single-molecule, real-time sequencing platforms. RD was highly accurate in determining repeat sizes of 609 blood-derived samples from Huntington's disease individuals and did not require prior knowledge of the flanking sequences. Furthermore, RD can be used to identify alleles with interruptions and provide a measure of repeat instability within an individual. RD is therefore highly versatile and may find applications in the diagnosis of expanded repeat disorders and in the development of novel therapies.
Collapse
Affiliation(s)
- Alysha S Taylor
- UK Dementia Research Institute, Cardiff University, Hadyn Ellis Building, Maindy Road, Cardiff, CF24 4HQ, UK
| | - Dinis Barros
- Centre for Integrative Genomics, University of Lausanne, Bâtiment Génopode, 1015 Lausanne, Switzerland
| | - Nastassia Gobet
- Centre for Integrative Genomics, University of Lausanne, Bâtiment Génopode, 1015 Lausanne, Switzerland
| | - Thierry Schuepbach
- Vital-IT Group, Swiss Institute of Bioinformatics, 1015 Lausanne, Switzerland
- Newbiologix, Ch. De la corniche 6-8, 1066 Epalinges, Switzerland
| | - Branduff McAllister
- MRC Centre for Neuropsychiatric Genetics and Genomics, Cardiff University, Hadyn Ellis Building, Maindy Road, Cardiff CF24 4HQ, UK
- Molecular Neurogenetics Unit, Center for Genomic Medicine, Massachusetts General Hospital, Boston, MA 02114, USA
| | - Lorene Aeschbach
- Centre for Integrative Genomics, University of Lausanne, Bâtiment Génopode, 1015 Lausanne, Switzerland
| | - Emma L Randall
- UK Dementia Research Institute, Cardiff University, Hadyn Ellis Building, Maindy Road, Cardiff, CF24 4HQ, UK
| | - Evgeniya Trofimenko
- Centre for Integrative Genomics, University of Lausanne, Bâtiment Génopode, 1015 Lausanne, Switzerland
- Sorbonne Université, École normale supérieure, PSL University, CNRS, Laboratoire des biomolécules, LBM, 75005 Paris, France
| | - Eleanor R Heuchan
- UK Dementia Research Institute, Cardiff University, Hadyn Ellis Building, Maindy Road, Cardiff, CF24 4HQ, UK
| | - Paula Barszcz
- Centre for Integrative Genomics, University of Lausanne, Bâtiment Génopode, 1015 Lausanne, Switzerland
| | - Marc Ciosi
- School of Molecular Biosciences, College of Medical, Veterinary and Life Sciences, Davidson Building, University of Glasgow, Glasgow, G12 8QQ, UK
| | - Joanne Morgan
- MRC Centre for Neuropsychiatric Genetics and Genomics, Cardiff University, Hadyn Ellis Building, Maindy Road, Cardiff CF24 4HQ, UK
| | | | - Alice E Davidson
- UCL Institute of Ophthalmology, 11-43 Bath Street, London, EC1V 9EL UK
| | - Thomas H Massey
- MRC Centre for Neuropsychiatric Genetics and Genomics, Cardiff University, Hadyn Ellis Building, Maindy Road, Cardiff CF24 4HQ, UK
| | - Darren G Monckton
- School of Molecular Biosciences, College of Medical, Veterinary and Life Sciences, Davidson Building, University of Glasgow, Glasgow, G12 8QQ, UK
| | - Lesley Jones
- MRC Centre for Neuropsychiatric Genetics and Genomics, Cardiff University, Hadyn Ellis Building, Maindy Road, Cardiff CF24 4HQ, UK
| | | | - Ioannis Xenarios
- Centre for Integrative Genomics, University of Lausanne, Bâtiment Génopode, 1015 Lausanne, Switzerland
- Health2030 Genome Center, Ch des Mines 14, 1202 Genève, Switzerland
| | - Vincent Dion
- UK Dementia Research Institute, Cardiff University, Hadyn Ellis Building, Maindy Road, Cardiff, CF24 4HQ, UK
| |
Collapse
|
10
|
Dawson J, Baine-Savanhu FK, Ciosi M, Maxwell A, Monckton DG, Krause A. A probable cis-acting genetic modifier of Huntington disease frequent in individuals with African ancestry. HGG ADVANCES 2022; 3:100130. [PMID: 35935919 PMCID: PMC9352962 DOI: 10.1016/j.xhgg.2022.100130] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2021] [Accepted: 07/07/2022] [Indexed: 11/21/2022] Open
Abstract
Huntington disease (HD)is a dominantly inherited neurodegenerative disorder caused by the expansion of a polyglutamine encoding CAG repeat in the huntingtin gene. Recently, it has been established that disease severity in HD is best predicted by the number of pure CAG repeats rather than total glutamines encoded. Along with uncovering DNA repair gene variants as trans-acting modifiers of HD severity, these data reveal somatic expansion of the CAG repeat as a key driver of HD onset. Using high-throughput DNA sequencing, we have determined the precise sequence and somatic expansion profiles of the HTT repeat tract of 68 HD-affected and 158 HD-unaffected African ancestry individuals. A high level of HTT repeat sequence diversity was observed, with three likely African-specific alleles identified. In the most common disease allele (30 out of 68), the typical proline-encoding CCGCCA sequence was absent. This CCGCCA-loss disease allele was associated with an earlier age of diagnosis of approximately 7.1 years and occurred exclusively on haplotype B2. Although somatic expansion was associated with an earlier age of diagnosis in the study overall, the CCGCCA-loss disease allele displayed reduced somatic expansion relative to the typical HTT expansions in blood DNA. We propose that the CCGCCA loss occurring on haplotype B2 is an African cis-acting modifier that appears to alter disease diagnosis of HD through a mechanism that is not driven by somatic expansion. The assessment of a group of individuals from an understudied population has highlighted population-specific differences that emphasize the importance of studying genetically diverse populations in the context of disease.
Collapse
Affiliation(s)
- Jessica Dawson
- Division of Human Genetics, National Health Laboratory Service and School of Pathology, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg 2000, South Africa
| | - Fiona K. Baine-Savanhu
- Division of Human Genetics, National Health Laboratory Service and School of Pathology, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg 2000, South Africa
| | - Marc Ciosi
- Institute of Molecular, Cell and Systems Biology, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow G12 8QQ, UK
| | - Alastair Maxwell
- Institute of Molecular, Cell and Systems Biology, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow G12 8QQ, UK
| | - Darren G. Monckton
- Institute of Molecular, Cell and Systems Biology, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow G12 8QQ, UK
| | - Amanda Krause
- Division of Human Genetics, National Health Laboratory Service and School of Pathology, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg 2000, South Africa
- Corresponding author
| |
Collapse
|
11
|
Dolzhenko E, Weisburd B, Ibañez K, Rajan-Babu IS, Anyansi C, Bennett MF, Billingsley K, Carroll A, Clamons S, Danzi MC, Deshpande V, Ding J, Fazal S, Halman A, Jadhav B, Qiu Y, Richmond PA, Saunders CT, Scheffler K, van Vugt JJFA, Zwamborn RRAJ, Chong SS, Friedman JM, Tucci A, Rehm HL, Eberle MA. REViewer: haplotype-resolved visualization of read alignments in and around tandem repeats. Genome Med 2022; 14:84. [PMID: 35948990 PMCID: PMC9367089 DOI: 10.1186/s13073-022-01085-z] [Citation(s) in RCA: 18] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2021] [Accepted: 07/11/2022] [Indexed: 01/28/2023] Open
Abstract
BACKGROUND Expansions of short tandem repeats are the cause of many neurogenetic disorders including familial amyotrophic lateral sclerosis, Huntington disease, and many others. Multiple methods have been recently developed that can identify repeat expansions in whole genome or exome sequencing data. Despite the widely recognized need for visual assessment of variant calls in clinical settings, current computational tools lack the ability to produce such visualizations for repeat expansions. Expanded repeats are difficult to visualize because they correspond to large insertions relative to the reference genome and involve many misaligning and ambiguously aligning reads. RESULTS We implemented REViewer, a computational method for visualization of sequencing data in genomic regions containing long repeat expansions and FlipBook, a companion image viewer designed for manual curation of large collections of REViewer images. To generate a read pileup, REViewer reconstructs local haplotype sequences and distributes reads to these haplotypes in a way that is most consistent with the fragment lengths and evenness of read coverage. To create appropriate training materials for onboarding new users, we performed a concordance study involving 12 scientists involved in short tandem repeat research. We used the results of this study to create a user guide that describes the basic principles of using REViewer as well as a guide to the typical features of read pileups that correspond to low confidence repeat genotype calls. Additionally, we demonstrated that REViewer can be used to annotate clinically relevant repeat interruptions by comparing visual assessment results of 44 FMR1 repeat alleles with the results of triplet repeat primed PCR. For 38 of these alleles, the results of visual assessment were consistent with triplet repeat primed PCR. CONCLUSIONS Read pileup plots generated by REViewer offer an intuitive way to visualize sequencing data in regions containing long repeat expansions. Laboratories can use REViewer and FlipBook to assess the quality of repeat genotype calls as well as to visually detect interruptions or other imperfections in the repeat sequence and the surrounding flanking regions. REViewer and FlipBook are available under open-source licenses at https://github.com/illumina/REViewer and https://github.com/broadinstitute/flipbook respectively.
Collapse
Affiliation(s)
- Egor Dolzhenko
- grid.185669.50000 0004 0507 3954Illumina Inc., San Diego, CA 92122 USA
| | - Ben Weisburd
- grid.66859.340000 0004 0546 1623Program in Medical and Population Genetics, Broad Institute of MIT and Harvard, Cambridge, USA ,grid.32224.350000 0004 0386 9924Center for Genomic Medicine, Massachusetts General Hospital, Boston, USA
| | - Kristina Ibañez
- grid.4868.20000 0001 2171 1133William Harvey Research Institute, Queen Mary University of London, London, EC1M 6BQ UK
| | - Indhu-Shree Rajan-Babu
- grid.17091.3e0000 0001 2288 9830Department of Medical Genetics, University of British Columbia and Children’s & Women’s Hospital, Vancouver, BC V6H3N1 Canada ,grid.13097.3c0000 0001 2322 6764Department of Medical and Molecular Genetics, King’s College London, Strand, London, WC2R 2LS UK
| | - Christine Anyansi
- grid.185669.50000 0004 0507 3954Illumina Inc., San Diego, CA 92122 USA
| | - Mark F. Bennett
- grid.1042.70000 0004 0432 4889Population Health and Immunity Division, The Walter and Eliza Hall Institute of Medical Research, Parkville, VIC 3052 Australia ,grid.1008.90000 0001 2179 088XDepartment of Medical Biology, University of Melbourne, Parkville, VIC 3052 Australia ,grid.410678.c0000 0000 9374 3516Epilepsy Research Centre, Department of Medicine, University of Melbourne, Austin Health, Heidelberg, VIC 3084 Australia
| | - Kimberley Billingsley
- grid.419475.a0000 0000 9372 4913Center for Alzheimer’s and Related Dementias, National Institute on Aging, Bethesda, MD USA ,grid.419475.a0000 0000 9372 4913Laboratory of Neurogenetics, National Institute on Aging, Bethesda, MD USA
| | - Ashley Carroll
- grid.185669.50000 0004 0507 3954Illumina Inc., San Diego, CA 92122 USA
| | - Samuel Clamons
- grid.185669.50000 0004 0507 3954Illumina Inc., San Diego, CA 92122 USA
| | - Matt C. Danzi
- grid.26790.3a0000 0004 1936 8606Dr. John T. Macdonald Foundation Department of Human Genetics and John P. Hussman Institute for Human Genomics, University of Miami, Miller School of Medicine, Miami, FL 33136 USA
| | - Viraj Deshpande
- grid.185669.50000 0004 0507 3954Illumina Inc., San Diego, CA 92122 USA
| | - Jinhui Ding
- grid.419475.a0000 0000 9372 4913Computational Biology Group, Laboratory of Neurogenetics, National Institute on Aging, NIH, Bethesda, MD 20892 USA
| | - Sarah Fazal
- grid.26790.3a0000 0004 1936 8606Dr. John T. Macdonald Foundation Department of Human Genetics and John P. Hussman Institute for Human Genomics, University of Miami, Miller School of Medicine, Miami, FL 33136 USA
| | - Andreas Halman
- grid.1055.10000000403978434Peter MacCallum Cancer Centre, Melbourne, VIC 3000 Australia ,grid.1008.90000 0001 2179 088XSir Peter MacCallum Department of Oncology, The University of Melbourne, Parkville, VIC 3010 Australia
| | - Bharati Jadhav
- grid.59734.3c0000 0001 0670 2351Department of Genetics and Genomic Sciences and Mindich Child Health and Development Institute, Icahn School of Medicine at Mount Sinai, New York, NY 10029 USA
| | - Yunjiang Qiu
- grid.185669.50000 0004 0507 3954Illumina Inc., San Diego, CA 92122 USA
| | - Phillip A. Richmond
- grid.414137.40000 0001 0684 7788BC Children’s Hospital Research Institute, Vancouver, BC V5Z 4H4 Canada
| | | | - Konrad Scheffler
- grid.185669.50000 0004 0507 3954Illumina Inc., San Diego, CA 92122 USA
| | - Joke J. F. A. van Vugt
- grid.5477.10000000120346234Department of Neurology, University Medical Center Utrecht Brain Center, Utrecht University, Utrecht, The Netherlands
| | - Ramona R. A. J. Zwamborn
- grid.5477.10000000120346234Department of Neurology, University Medical Center Utrecht Brain Center, Utrecht University, Utrecht, The Netherlands
| | | | - Samuel S. Chong
- grid.4280.e0000 0001 2180 6431Department of Pediatrics, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, 119228 Singapore ,grid.4280.e0000 0001 2180 6431Department of Obstetrics and Gynecology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, 119228 Singapore ,grid.412106.00000 0004 0621 9599Department of Laboratory Medicine, National University Hospital, Singapore, 119074 Singapore
| | - Jan M. Friedman
- grid.17091.3e0000 0001 2288 9830Department of Medical Genetics, University of British Columbia and Children’s & Women’s Hospital, Vancouver, BC V6H3N1 Canada
| | - Arianna Tucci
- grid.4868.20000 0001 2171 1133William Harvey Research Institute, Queen Mary University of London, London, EC1M 6BQ UK
| | - Heidi L. Rehm
- grid.66859.340000 0004 0546 1623Program in Medical and Population Genetics, Broad Institute of MIT and Harvard, Cambridge, USA ,grid.32224.350000 0004 0386 9924Center for Genomic Medicine, Massachusetts General Hospital, Boston, USA
| | - Michael A. Eberle
- grid.185669.50000 0004 0507 3954Illumina Inc., San Diego, CA 92122 USA
| |
Collapse
|
12
|
Jang JH, Yoon SJ, Kim SK, Cho JW, Kim JW. Detection Methods and Status of CAT Interruption of ATXN1 in Korean Patients With Spinocerebellar Ataxia Type 1. Ann Lab Med 2022; 42:274-277. [PMID: 34635619 PMCID: PMC8548249 DOI: 10.3343/alm.2022.42.2.274] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2021] [Revised: 02/09/2021] [Accepted: 09/17/2021] [Indexed: 11/19/2022] Open
Abstract
Spinocerebellar ataxia type 1 (SCA1) is an autosomal dominant disease caused by abnormal CAG repeat expansion in the ataxin 1 gene (ATXN1). The presence of CAT interruption(s) is important for diagnosing SCA1 in patients with 39–44 repeat alleles, as only uninterrupted alleles are considered abnormal. Determining the CAT interruption status might also be important for patients with >44 repeats, as the length of the longest uninterrupted CAG repeat stretch has been correlated with age at SCA1 onset. We detected CAT interruption(s) in the archived samples of Korean SCA1 patients using a traditional restriction enzyme method and validated the usefulness of a fluorescence-based tethering PCR procedure. Among the 2,312 alleles analyzed from 1,156 patients, we found 17 expanded alleles with ≥39 repeats, 71% of which harbored 39–44 repeats. Restriction enzyme method of six samples (four with 39–44 repeats and two with >44 repeats) revealed that none of the expanded alleles had CAT interruption(s). Tethering PCR showed the characteristic electropherogram pattern expected without CAT interruption(s). Along with the enzyme restriction method, tethering PCR can be applied to determine the number of allele repeats and provide information on CAT interruption(s) in clinical laboratories.
Collapse
Affiliation(s)
- Ja-Hyun Jang
- Department of Laboratory Medicine and Genetics, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - Sun Joo Yoon
- Department of Laboratory Medicine and Genetics, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - Sun-Kyung Kim
- Department of Laboratory Medicine and Genetics, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - Jin Whan Cho
- Department of Neurology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.,Neuroscience Center, Samsung Medical Center, Seoul, Korea
| | - Jong-Won Kim
- Department of Laboratory Medicine and Genetics, Sungkyunkwan University School of Medicine, Seoul, Korea
| |
Collapse
|
13
|
Fourier A, Quadrio I. Proteinopathies associated to repeat expansion disorders. J Neural Transm (Vienna) 2022; 129:173-185. [DOI: 10.1007/s00702-021-02454-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2021] [Accepted: 12/13/2021] [Indexed: 12/11/2022]
|
14
|
Huang H, Toker N, Burr E, Okoro J, Moog M, Hearing C, Lagalwar S. Intercellular Propagation and Aggregate Seeding of Mutant Ataxin-1. J Mol Neurosci 2021; 72:708-718. [PMID: 34826062 PMCID: PMC8986690 DOI: 10.1007/s12031-021-01944-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2021] [Accepted: 11/06/2021] [Indexed: 01/07/2023]
Abstract
Intercellular propagation of aggregated protein inclusions along actin-based tunneling nanotubes (TNTs) has been reported as a means of pathogenic spread in Alzheimer’s, Parkinson’s, and Huntington’s diseases. Propagation of oligomeric-structured polyglutamine-expanded ataxin-1 (Atxn1[154Q]) has been reported in the cerebellum of a Spinocerebellar ataxia type 1 (SCA1) knock-in mouse to correlate with disease propagation. In this study, we investigated whether a physiologically relevant polyglutamine-expanded ATXN1 protein (ATXN1[82Q]) could propagate intercellularly. Using a cerebellar-derived live cell model, we observed ATXN1 aggregates form in the nucleus, subsequently form in the cytoplasm, and finally, propagate to neighboring cells along actin-based intercellular connections. Additionally, we observed the facilitation of aggregate-resistant proteins into aggregates given the presence of aggregation-prone proteins within cells. Taken together, our results support a pathogenic role of intercellular propagation of polyglutamine-expanded ATXN1 inclusions.
Collapse
Affiliation(s)
- Haoyang Huang
- Neuroscience Program, Skidmore College, Saratoga Springs, NY, USA
| | - Nicholas Toker
- Neuroscience Program, Skidmore College, Saratoga Springs, NY, USA
| | - Eliza Burr
- Neuroscience Program, Skidmore College, Saratoga Springs, NY, USA
| | - Jeff Okoro
- Neuroscience Program, Skidmore College, Saratoga Springs, NY, USA
| | - Maia Moog
- Neuroscience Program, Skidmore College, Saratoga Springs, NY, USA
| | - Casey Hearing
- Neuroscience Program, Skidmore College, Saratoga Springs, NY, USA
| | - Sarita Lagalwar
- Neuroscience Program, Skidmore College, Saratoga Springs, NY, USA.
| |
Collapse
|
15
|
Cao L, Yan Y, Zhao G. NOTCH2NLC-related repeat expansion disorders: an expanding group of neurodegenerative disorders. Neurol Sci 2021; 42:4055-4062. [PMID: 34333668 DOI: 10.1007/s10072-021-05498-3] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2021] [Accepted: 07/18/2021] [Indexed: 12/22/2022]
Abstract
The NOTCH2NLC gene 5' untranslated region (UTR) GGC repeat expansion mutations were identified as a genetic contributor of neuronal intranuclear inclusion disease (NIID) in 2019. Since then, the number of reported cases with NOTCH2NLC GGC repeat expansion in Asian and European populations has increased rapidly, indicating that the expanded mutation not only leads to the onset or progression of the NIID, but also may play an important role in multiple progressive neurological disorders, including Parkinson's disease, essential tremor, multiple system atrophy, Alzheimer's disease, frontotemporal dementia, amyotrophic lateral sclerosis, leukoencephalopathy, and oculopharyngodistal myopathy type 3. Nevertheless, the underlying pathogenic mechanism of the NOTCH2NLC 5' UTR region GGC repeat expansion in these disorders remains largely unknown. This review aims to present recent breakthroughs on this mutation and improve our knowledge of a newly defined spectrum of disease: NOTCH2NLC-related repeat expansion disorder.
Collapse
Affiliation(s)
- Lanxiao Cao
- Department of Neurology, The Fourth Affiliated Hospital, Zhejiang University School of Medicine, N1 Shangcheng Avenue, Yiwu, 322000, Zhejiang Province, China
| | - Yaping Yan
- Department of Neurology, The Second Affiliated Hospital, Zhejiang University School of Medicine, No.88 Jiefang Road, Hangzhou, 310009, Zhejiang Province, China.
| | - Guohua Zhao
- Department of Neurology, The Fourth Affiliated Hospital, Zhejiang University School of Medicine, N1 Shangcheng Avenue, Yiwu, 322000, Zhejiang Province, China.
- Department of Neurology, The Second Affiliated Hospital, Zhejiang University School of Medicine, No.88 Jiefang Road, Hangzhou, 310009, Zhejiang Province, China.
| |
Collapse
|
16
|
Genomic Mosaicism Formed by Somatic Variation in the Aging and Diseased Brain. Genes (Basel) 2021; 12:genes12071071. [PMID: 34356087 PMCID: PMC8305509 DOI: 10.3390/genes12071071] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2021] [Revised: 07/09/2021] [Accepted: 07/12/2021] [Indexed: 12/22/2022] Open
Abstract
Over the past 20 years, analyses of single brain cell genomes have revealed that the brain is composed of cells with myriad distinct genomes: the brain is a genomic mosaic, generated by a host of DNA sequence-altering processes that occur somatically and do not affect the germline. As such, these sequence changes are not heritable. Some processes appear to occur during neurogenesis, when cells are mitotic, whereas others may also function in post-mitotic cells. Here, we review multiple forms of DNA sequence alterations that have now been documented: aneuploidies and aneusomies, smaller copy number variations (CNVs), somatic repeat expansions, retrotransposons, genomic cDNAs (gencDNAs) associated with somatic gene recombination (SGR), and single nucleotide variations (SNVs). A catch-all term of DNA content variation (DCV) has also been used to describe the overall phenomenon, which can include multiple forms within a single cell’s genome. A requisite step in the analyses of genomic mosaicism is ongoing technology development, which is also discussed. Genomic mosaicism alters one of the most stable biological molecules, DNA, which may have many repercussions, ranging from normal functions including effects of aging, to creating dysfunction that occurs in neurodegenerative and other brain diseases, most of which show sporadic presentation, unlinked to causal, heritable genes.
Collapse
|
17
|
Elsaey MA, Namikawa K, Köster RW. Genetic Modeling of the Neurodegenerative Disease Spinocerebellar Ataxia Type 1 in Zebrafish. Int J Mol Sci 2021; 22:7351. [PMID: 34298970 PMCID: PMC8306488 DOI: 10.3390/ijms22147351] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2021] [Revised: 06/29/2021] [Accepted: 07/06/2021] [Indexed: 12/26/2022] Open
Abstract
Dominant spinocerebellar ataxias (SCAs) are progredient neurodegenerative diseases commonly affecting the survival of Purkinje cells (PCs) in the human cerebellum. Spinocerebellar ataxia type 1 (SCA1) is caused by the mutated ataxin1 (Atx1) gene product, in which a polyglutamine stretch encoded by CAG repeats is extended in affected SCA1 patients. As a monogenetic disease with the Atx1-polyQ protein exerting a gain of function, SCA1 can be genetically modelled in animals by cell type-specific overexpression. We have established a transgenic PC-specific SCA1 model in zebrafish coexpressing the fluorescent reporter protein mScarlet together with either human wild type Atx1[30Q] as control or SCA1 patient-derived Atx1[82Q]. SCA1 zebrafish display an age-dependent PC degeneration starting at larval stages around six weeks postfertilization, which continuously progresses during further juvenile and young adult stages. Interestingly, PC degeneration is observed more severely in rostral than in caudal regions of the PC population. Although such a neuropathology resulted in no gross locomotor control deficits, SCA1-fish with advanced PC loss display a reduced exploratory behaviour. In vivo imaging in this SCA1 model may help to better understand such patterned PC death known from PC neurodegeneration diseases, to elucidate disease mechanisms and to provide access to neuroprotective compound characterization in vivo.
Collapse
Affiliation(s)
- Mohamed A. Elsaey
- Division of Cellular & Molecular Neurobiology, Zoological Institute, Technische Universität Braunschweig, Spielmannstraße 7, 38106 Braunschweig, Germany;
- Zoology Department, Faculty of Science, Suez Canal University, Ismailia 41522, Egypt
| | - Kazuhiko Namikawa
- Division of Cellular & Molecular Neurobiology, Zoological Institute, Technische Universität Braunschweig, Spielmannstraße 7, 38106 Braunschweig, Germany;
| | - Reinhard W. Köster
- Division of Cellular & Molecular Neurobiology, Zoological Institute, Technische Universität Braunschweig, Spielmannstraße 7, 38106 Braunschweig, Germany;
| |
Collapse
|
18
|
Ma D, Tan YJ, Ng ASL, Ong HL, Sim W, Lim WK, Teo JX, Ng EYL, Lim EC, Lim EW, Chan LL, Tan LCS, Yi Z, Tan EK. Association of NOTCH2NLC Repeat Expansions With Parkinson Disease. JAMA Neurol 2021; 77:1559-1563. [PMID: 32852534 DOI: 10.1001/jamaneurol.2020.3023] [Citation(s) in RCA: 58] [Impact Index Per Article: 19.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Importance The presence of Notch homolog 2 N-terminal-like C (NOTCH2NLC) repeat expansions are associated with neuronal intranuclear inclusion body disease (NIID), with varied neurological signs, including neuropathy, ataxia, parkinsonism, and tremor. To date, genetic screening of NOTCH2NLC GGC repeats in a cohort with typical Parkinson disease (PD) appears not to have been reported. Objective To investigate if NOTCH2NLC GGC expansions are present in a cohort of patients with PD and controls. Design, Setting, and Participants This case-control study was conducted in 2 tertiary movement disorder centers in Singapore. Participants were recruited and followed up from January 2005 to January 2020. The presence of NOTCH2NLC GGC expansion repeats was screened using polymerase chain reaction tests, and representative samples were verified with long-read genome sequencing. Main Outcomes and Measures Qualitative and quantitative comparisons between participants with sporadic PD, healthy control participants, and individuals with NIID. Results A total of 2076 participants, including 1000 with sporadic PD (600 men [60.0%]; mean age at onset, 62.6 [7.7] years) and 1076 healthy controls (581 men [54.0%]; mean age at study recruitment, 54.9 [9.4] years) were recruited. A total of 13 patients with PD and no healthy control participants were identified as carrying NOTCH2NLC GGC repeat expansions of more than 40 units; the frequency of more than 40 repeat expansions was higher in participants with PD than controls (P < .001). None of the patients with PD were carriers of known PD-associated genes. Ten patients with PD carried a GGC expansion of between 41 and 64 repeats (1% of patients with sporadic PD; mean [SD], 49.4 [9.2] repeats). The other 3 patients carried GGC repeats of 79 or more units, 2 with 122 and 79 repeats, respectively, exhibited typical parkinsonism and were responsive to small dosages of levodopa over many years, with no clinical or imaging features of NIID. The other patient with PD, who had 130 repeats, only developed cognitive impairment before death. Within the GGC expansions, there was no GGA interruptions (mean [SD] GGA percentage in the 3 patients with PD vs patients with NIID, 0% vs 12% [9%]), and the frequency of AGC interruptions was 3 times higher in these patients with PD than patients with NIID (mean [SD], 25% [12%] vs 8% [8%]). Conclusions and Relevance This study demonstrated that individuals with sporadic PD who carried pathogenic NOTCH2NLC GGC repeat expansions can present with typical parkinsonism, requiring only low dosages of levodopa, without displaying other clinical or imaging features of NIID even after several years of follow-up. None of the patients with PD had GGA interruptions within their GGC expansions, and the frequency of AGC interruptions was much higher than that of patients with NIID. The functional significance of a higher moderate repeat expansion in patients with PD compared with healthy controls needs to be further investigated.
Collapse
Affiliation(s)
- Dongrui Ma
- Department of Neurology, Singapore General Hospital, Singapore
| | - Yi Jayne Tan
- National Neuroscience Institute, Department of Neurology, Tan Tock Seng Hospital, Singapore
| | - Adeline S L Ng
- National Neuroscience Institute, Department of Neurology, Tan Tock Seng Hospital, Singapore.,Neuroscience and Behavioural Disorders, Duke-NUS Medical School, Singapore
| | - Helen L Ong
- Department of Clinical Translational Research, Singapore General Hospital, Singapore
| | - Weiying Sim
- Department of Clinical Translational Research, Singapore General Hospital, Singapore
| | - Weng Khong Lim
- SingHealth Duke-NUS Institute of Precision Medicine, Singapore.,Cancer and Stem Cell Biology Program, Duke-NUS Medical School, Singapore
| | - Jing Xian Teo
- SingHealth Duke-NUS Institute of Precision Medicine, Singapore
| | - Ebonne Y L Ng
- National Neuroscience Institute, Department of Neurology, Singapore General Hospital, Singapore
| | - Ee-Chien Lim
- National Neuroscience Institute, Department of Neurology, Singapore General Hospital, Singapore
| | - Ee-Wei Lim
- National Neuroscience Institute, Department of Neurology, Singapore General Hospital, Singapore
| | - Ling-Ling Chan
- Department of Radiology, Singapore General Hospital, Singapore
| | - Louis C S Tan
- National Neuroscience Institute, Department of Neurology, Tan Tock Seng Hospital, Singapore
| | - Zhao Yi
- Department of Clinical Translational Research, Singapore General Hospital, Singapore
| | - Eng-King Tan
- Neuroscience and Behavioural Disorders, Duke-NUS Medical School, Singapore.,National Neuroscience Institute, Department of Neurology, Singapore General Hospital, Singapore
| |
Collapse
|
19
|
Brooker SM, Edamakanti CR, Akasha SM, Kuo SH, Opal P. Spinocerebellar ataxia clinical trials: opportunities and challenges. Ann Clin Transl Neurol 2021; 8:1543-1556. [PMID: 34019331 PMCID: PMC8283160 DOI: 10.1002/acn3.51370] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2021] [Revised: 04/02/2021] [Accepted: 04/05/2021] [Indexed: 12/14/2022] Open
Abstract
The spinocerebellar ataxias (SCAs) are a group of dominantly inherited diseases that share the defining feature of progressive cerebellar ataxia. The disease process, however, is not confined to the cerebellum; other areas of the brain, in particular, the brainstem, are also affected, resulting in a high burden of morbidity and mortality. Currently, there are no disease‐modifying treatments for the SCAs, but preclinical research has led to the development of therapeutic agents ripe for testing in patients. Unfortunately, due to the rarity of these diseases and their slow and variable progression, there are substantial hurdles to overcome in conducting clinical trials. While the epidemiological features of the SCAs are immutable, the feasibility of conducting clinical trials is being addressed through a combination of strategies. These include improvements in clinical outcome measures, the identification of imaging and fluid biomarkers, and innovations in clinical trial design. In this review, we highlight current challenges in initiating clinical trials for the SCAs and also discuss pathways for researchers and clinicians to mitigate these challenges and harness opportunities for clinical trial development.
Collapse
Affiliation(s)
- Sarah M Brooker
- Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, Illinois, USA
| | | | - Sara M Akasha
- Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, Illinois, USA
| | - Sheng-Han Kuo
- Department of Neurology, Columbia University, New York, New York, USA.,Initiative for Columbia Ataxia and Tremor, Columbia University, New York, New York, USA
| | - Puneet Opal
- Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, Illinois, USA
| |
Collapse
|
20
|
Depienne C, Mandel JL. 30 years of repeat expansion disorders: What have we learned and what are the remaining challenges? Am J Hum Genet 2021; 108:764-785. [PMID: 33811808 DOI: 10.1016/j.ajhg.2021.03.011] [Citation(s) in RCA: 162] [Impact Index Per Article: 54.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2020] [Accepted: 03/05/2021] [Indexed: 12/13/2022] Open
Abstract
Tandem repeats represent one of the most abundant class of variations in human genomes, which are polymorphic by nature and become highly unstable in a length-dependent manner. The expansion of repeat length across generations is a well-established process that results in human disorders mainly affecting the central nervous system. At least 50 disorders associated with expansion loci have been described to date, with half recognized only in the last ten years, as prior methodological difficulties limited their identification. These limitations still apply to the current widely used molecular diagnostic methods (exome or gene panels) and thus result in missed diagnosis detrimental to affected individuals and their families, especially for disorders that are very rare and/or clinically not recognizable. Most of these disorders have been identified through family-driven approaches and many others likely remain to be identified. The recent development of long-read technologies provides a unique opportunity to systematically investigate the contribution of tandem repeats and repeat expansions to the genetic architecture of human disorders. In this review, we summarize the current and most recent knowledge about the genetics of repeat expansion disorders and the diversity of their pathophysiological mechanisms and outline the perspectives of developing personalized treatments in the future.
Collapse
|
21
|
Mangin A, de Pontual L, Tsai YC, Monteil L, Nizon M, Boisseau P, Mercier S, Ziegle J, Harting J, Heiner C, Gourdon G, Tomé S. Robust Detection of Somatic Mosaicism and Repeat Interruptions by Long-Read Targeted Sequencing in Myotonic Dystrophy Type 1. Int J Mol Sci 2021; 22:2616. [PMID: 33807660 PMCID: PMC7962047 DOI: 10.3390/ijms22052616] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2021] [Revised: 02/26/2021] [Accepted: 02/27/2021] [Indexed: 02/07/2023] Open
Abstract
Myotonic dystrophy type 1 (DM1) is the most complex and variable trinucleotide repeat disorder caused by an unstable CTG repeat expansion, reaching up to 4000 CTG in the most severe cases. The genetic and clinical variability of DM1 depend on the sex and age of the transmitting parent, but also on the CTG repeat number, presence of repeat interruptions and/or on the degree of somatic instability. Currently, it is difficult to simultaneously and accurately determine these contributing factors in DM1 patients due to the limitations of gold standard methods used in molecular diagnostics and research laboratories. Our study showed the efficiency of the latest PacBio long-read sequencing technology to sequence large CTG trinucleotides, detect multiple and single repeat interruptions and estimate the levels of somatic mosaicism in DM1 patients carrying complex CTG repeat expansions inaccessible to most methods. Using this innovative approach, we revealed the existence of de novo CCG interruptions associated with CTG stabilization/contraction across generations in a new DM1 family. We also demonstrated that our method is suitable to sequence the DM1 locus and measure somatic mosaicism in DM1 families carrying more than 1000 pure CTG repeats. Better characterization of expanded alleles in DM1 patients can significantly improve prognosis and genetic counseling, not only in DM1 but also for other tandem DNA repeat disorders.
Collapse
Affiliation(s)
- Antoine Mangin
- Centre de Recherche en Myologie, Inserm, Institut de Myologie, Sorbonne Université, F-75013 Paris, France; (A.M.); (L.d.P.); (G.G.)
- Dementia Research Institute, Cardiff University, Cardiff CF10 3AT, UK
| | - Laure de Pontual
- Centre de Recherche en Myologie, Inserm, Institut de Myologie, Sorbonne Université, F-75013 Paris, France; (A.M.); (L.d.P.); (G.G.)
| | - Yu-Chih Tsai
- Pacific Biosciences, Menlo Park, CA 94025, USA; (Y.-C.T.); (J.Z.); (J.H.); (C.H.)
| | - Laetitia Monteil
- Genetics Department of the Hospital of Toulouse, F-31059 Toulouse, France;
| | - Mathilde Nizon
- CHU de Nantes, Service de Génétique Médicale, Laboratoire de Génétique Moléculaire, F-44000 Nantes, France; (M.N.); (P.B.)
| | - Pierre Boisseau
- CHU de Nantes, Service de Génétique Médicale, Laboratoire de Génétique Moléculaire, F-44000 Nantes, France; (M.N.); (P.B.)
| | - Sandra Mercier
- CHU Nantes, Service de Génétique Médicale, Centre de Référence des Maladies Neuromusculaires AOC, F-44000 Nantes, France;
| | - Janet Ziegle
- Pacific Biosciences, Menlo Park, CA 94025, USA; (Y.-C.T.); (J.Z.); (J.H.); (C.H.)
| | - John Harting
- Pacific Biosciences, Menlo Park, CA 94025, USA; (Y.-C.T.); (J.Z.); (J.H.); (C.H.)
| | - Cheryl Heiner
- Pacific Biosciences, Menlo Park, CA 94025, USA; (Y.-C.T.); (J.Z.); (J.H.); (C.H.)
| | - Geneviève Gourdon
- Centre de Recherche en Myologie, Inserm, Institut de Myologie, Sorbonne Université, F-75013 Paris, France; (A.M.); (L.d.P.); (G.G.)
| | - Stéphanie Tomé
- Centre de Recherche en Myologie, Inserm, Institut de Myologie, Sorbonne Université, F-75013 Paris, France; (A.M.); (L.d.P.); (G.G.)
| |
Collapse
|
22
|
Lian M, Zhao M, Phang GP, Soong YT, Yoon CS, Lee CG, Law HY, Chong SS. Rapid Molecular Screen of Spinocerebellar Ataxia Types 1, 2, and 3 by Triplet-Primed PCR and Melting Curve Analysis. J Mol Diagn 2021; 23:565-576. [PMID: 33618058 DOI: 10.1016/j.jmoldx.2021.01.012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2020] [Revised: 12/02/2020] [Accepted: 01/12/2021] [Indexed: 11/16/2022] Open
Abstract
The autosomal dominantly inherited spinocerebellar ataxias (SCAs) can be caused by dynamic mutations of short tandem repeats within various genes. Because of the significant clinical overlap among the various SCA types, molecular screening of multiple genetic loci by fluorescent PCR and capillary electrophoresis is necessary to identify the causative repeat expansion. We describe a simple, rapid, and inexpensive strategy to screen for CAG repeat expansion mutations at the ATXN1, ATXN2, and ATXN3 loci using melting curve analysis of triplet-primed PCR products. Plasmid DNAs of known repeat sizes were used to generate threshold melt peak temperatures, which rapidly and effectively distinguish samples carrying an expanded allele from those carrying nonexpanded alleles. Melting curve analysis-positive samples were confirmed by capillary electrophoresis sizing of the triplet-primed PCR products. All three assays achieved 100% sensitivity, with 95% CIs of 67.86% to 100% (SCA1), 74.65% to 100% (SCA2), and 91.58% to 100% (SCA3). The SCA1 assay also achieved 100% specificity (95% CI, 97.52%-100%), whereas the SCA2 and SCA3 assays achieved specificity of 99.46% (95% CI, 96.56%-99.97%) and 99.32% (95% CI, 95.70%-99.96%), respectively. These screening assays provide robust and highly accurate detection of expanded alleles and are amenable to large-scale screening while minimizing the need for capillary electrophoresis sizing for every sample.
Collapse
Affiliation(s)
- Mulias Lian
- Khoo Teck Puat-National University Children's Medical Institute, National University Health System, Singapore
| | - Mingjue Zhao
- Department of Pediatrics, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
| | - Gui-Ping Phang
- Department of Pediatrics, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
| | - Yun-Ting Soong
- Department of Pediatrics, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
| | - Chui-Sheun Yoon
- Department of Pediatric Medicine, KK Women's and Children's Hospital, Singapore
| | - Caroline G Lee
- Department of Biochemistry, Yong Loo Lin School of Medicine, National University of Singapore, Singapore; Cancer and Stem Cell Biology Program, Duke-NUS Graduate Medical School, Singapore; Division of Medical Sciences, National Cancer Center Singapore, Singapore
| | - Hai-Yang Law
- Department of Pediatric Medicine, KK Women's and Children's Hospital, Singapore; Pediatrics Academic Clinical Program, Duke-NUS Graduate Medical School, Singapore
| | - Samuel S Chong
- Khoo Teck Puat-National University Children's Medical Institute, National University Health System, Singapore; Department of Pediatrics, Yong Loo Lin School of Medicine, National University of Singapore, Singapore; Department of Laboratory Medicine, National University Hospital, Singapore.
| |
Collapse
|
23
|
Khampang S, Parnpai R, Mahikul W, Easley CA, Cho IK, Chan AWS. CAG repeat instability in embryonic stem cells and derivative spermatogenic cells of transgenic Huntington's disease monkey. J Assist Reprod Genet 2021; 38:1215-1229. [PMID: 33611676 DOI: 10.1007/s10815-021-02106-3] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2020] [Accepted: 02/08/2021] [Indexed: 12/16/2022] Open
Abstract
PURPOSE The expansion of CAG (glutamine; Q) trinucleotide repeats (TNRs) predominantly occurs through male lineage in Huntington's disease (HD). As a result, offspring will have larger CAG repeats compared to their fathers, which causes an earlier onset of the disease called genetic anticipation. This study aims to develop a novel in vitro model to replicate CAG repeat instability in early spermatogenesis and demonstrate the biological process of genetic anticipation by using the HD stem cell model for the first time. METHODS HD rhesus monkey embryonic stem cells (rESCs) were cultured in vitro for an extended period. Male rESCs were used to derive spermatogenic cells in vitro with a 10-day differentiation. The assessment of CAG repeat instability was performed by GeneScan and curve fit analysis. RESULTS Spermatogenic cells derived from rESCs exhibit progressive expansion of CAG repeats with high daily expansion rates compared to the extended culture of rESCs. The expansion of CAG repeats is cell type-specific and size-dependent. CONCLUSIONS Here, we report a novel stem cell model that replicates genome instability and CAG repeat expansion in in vitro derived HD monkey spermatogenic cells. The in vitro spermatogenic cell model opens a new opportunity for studying TNR instability and the underlying mechanism of genetic anticipation, not only in HD but also in other TNR diseases.
Collapse
Affiliation(s)
- Sujittra Khampang
- Division of Neuropharmacology and Neurologic Diseases, Yerkes National Primate Research Center, Atlanta, GA, USA.,Embryo Technology and Stem Cell Research Center, School of Biotechnology, Suranaree University of Technology, Nakhon Ratchasima, Thailand
| | - Rangsun Parnpai
- Embryo Technology and Stem Cell Research Center, School of Biotechnology, Suranaree University of Technology, Nakhon Ratchasima, Thailand
| | - Wiriya Mahikul
- Faculty of Medicine and Public Health, HRH Princess Chulabhorn College of Medical Science, Chulabhorn Royal Academy, Bangkok, Thailand
| | - Charles A Easley
- Division of Neuropharmacology and Neurologic Diseases, Yerkes National Primate Research Center, Atlanta, GA, USA.,Department of Environmental Health Science, College of Public Health, University of Georgia, Athens, GA, USA.,Regenerative Bioscience Center, University of Georgia, Athens, GA, USA
| | - In Ki Cho
- Division of Neuropharmacology and Neurologic Diseases, Yerkes National Primate Research Center, Atlanta, GA, USA. .,Department of Human Genetics, Emory University, Atlanta, GA, 30322, USA.
| | - Anthony W S Chan
- Division of Neuropharmacology and Neurologic Diseases, Yerkes National Primate Research Center, Atlanta, GA, USA. .,Department of Human Genetics, Emory University, Atlanta, GA, 30322, USA.
| |
Collapse
|
24
|
Tejwani L, Lim J. Pathogenic mechanisms underlying spinocerebellar ataxia type 1. Cell Mol Life Sci 2020; 77:4015-4029. [PMID: 32306062 PMCID: PMC7541529 DOI: 10.1007/s00018-020-03520-z] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2019] [Revised: 03/06/2020] [Accepted: 04/06/2020] [Indexed: 02/06/2023]
Abstract
The family of hereditary cerebellar ataxias is a large group of disorders with heterogenous clinical manifestations and genetic etiologies. Among these, over 30 autosomal dominantly inherited subtypes have been identified, collectively referred to as the spinocerebellar ataxias (SCAs). Generally, the SCAs are characterized by a progressive gait impairment with classical cerebellar features, and in a subset of SCAs, accompanied by extra-cerebellar features. Beyond the common gait impairment and cerebellar atrophy, the wide range of additional clinical features observed across the SCAs is likely explained by the diverse set of mutated genes that encode proteins with seemingly disparate functional roles in nervous system biology. By synthesizing knowledge obtained from studies of the various SCAs over the past several decades, convergence onto a few key cellular changes, namely ion channel dysfunction and transcriptional dysregulation, has become apparent and may represent central mechanisms of cerebellar disease pathogenesis. This review will detail our current understanding of the molecular pathogenesis of the SCAs, focusing primarily on the first described autosomal dominant spinocerebellar ataxia, SCA1, as well as the emerging common core mechanisms across the various SCAs.
Collapse
Affiliation(s)
- Leon Tejwani
- Interdepartmental Neuroscience Program, Yale School of Medicine, 295 Congress Avenue, New Haven, CT, 06510, USA
- Department of Neuroscience, Yale School of Medicine, New Haven, CT, 06510, USA
| | - Janghoo Lim
- Interdepartmental Neuroscience Program, Yale School of Medicine, 295 Congress Avenue, New Haven, CT, 06510, USA.
- Department of Neuroscience, Yale School of Medicine, New Haven, CT, 06510, USA.
- Department of Genetics, Yale School of Medicine, New Haven, CT, 06510, USA.
- Program in Cellular Neuroscience, Neurodegeneration and Repair, Yale School of Medicine, New Haven, CT, 06510, USA.
- Yale Stem Cell Center, Yale School of Medicine, New Haven, CT, 06510, USA.
| |
Collapse
|
25
|
Proukakis C. Somatic mutations in neurodegeneration: An update. Neurobiol Dis 2020; 144:105021. [PMID: 32712267 DOI: 10.1016/j.nbd.2020.105021] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2020] [Revised: 06/12/2020] [Accepted: 07/13/2020] [Indexed: 12/20/2022] Open
Abstract
Mosaicism, the presence of genomic differences between cells due to post-zygotic somatic mutations, is widespread in the human body, including within the brain. A role for this in neurodegenerative diseases has long been hypothesised, and technical developments are now allowing the question to be addressed in detail. The rapidly accumulating evidence is discussed in this review, with a focus on recent developments. Somatic mutations of numerous types may occur, including single nucleotide variants (SNVs), copy number variants (CNVs), and retrotransposon insertions. They could act as initiators or risk factors, especially if they arise in development, although they could also result from the disease process, potentially contributing to progression. In common sporadic neurodegenerative disorders, relevant mutations have been reported in synucleinopathies, comprising somatic gains of SNCA in Parkinson's disease and multiple system atrophy, and in Alzheimer's disease, where a novel recombination mechanism leading to somatic variants of APP, as well as an excess of somatic SNVs affecting tau phosphorylation, have been reported. In Mendelian repeat expansion disorders, mosaicism due to somatic instability, first detected 25 years ago, has come to the forefront. Brain somatic SNVs occur in DNA repair disorders, and there is evidence for a role of several ALS genes in DNA repair. While numerous challenges, and need for further validation, remain, this new, or perhaps rediscovered, area of research has the potential to transform our understanding of neurodegeneration.
Collapse
Affiliation(s)
- Christos Proukakis
- Department of Clinical and Movement Neurosciences, Queen Square Institute of Neurology, University College London, London, UK.
| |
Collapse
|
26
|
Xu P, Pan F, Roland C, Sagui C, Weninger K. Dynamics of strand slippage in DNA hairpins formed by CAG repeats: roles of sequence parity and trinucleotide interrupts. Nucleic Acids Res 2020; 48:2232-2245. [PMID: 31974547 PMCID: PMC7049705 DOI: 10.1093/nar/gkaa036] [Citation(s) in RCA: 34] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2019] [Revised: 12/11/2019] [Accepted: 01/15/2020] [Indexed: 01/08/2023] Open
Abstract
DNA trinucleotide repeats (TRs) can exhibit dynamic expansions by integer numbers of trinucleotides that lead to neurodegenerative disorders. Strand slipped hairpins during DNA replication, repair and/or recombination may contribute to TR expansion. Here, we combine single-molecule FRET experiments and molecular dynamics studies to elucidate slipping dynamics and conformations of (CAG)n TR hairpins. We directly resolve slipping by predominantly two CAG units. The slipping kinetics depends on the even/odd repeat parity. The populated states suggest greater stability for 5′-AGCA-3′ tetraloops, compared with alternative 5′-CAG-3′ triloops. To accommodate the tetraloop, even(odd)-numbered repeats have an even(odd) number of hanging bases in the hairpin stem. In particular, a paired-end tetraloop (no hanging TR) is stable in (CAG)n = even, but such situation cannot occur in (CAG)n = odd, where the hairpin is “frustrated’’ and slips back and forth between states with one TR hanging at the 5′ or 3′ end. Trinucleotide interrupts in the repeating CAG pattern associated with altered disease phenotypes select for specific conformers with favorable loop sequences. Molecular dynamics provide atomic-level insight into the loop configurations. Reducing strand slipping in TR hairpins by sequence interruptions at the loop suggests disease-associated variations impact expansion mechanisms at the level of slipped hairpins.
Collapse
Affiliation(s)
- Pengning Xu
- Department of Physics, North Carolina State University, Raleigh, NC 27695-8202, USA
| | - Feng Pan
- Department of Physics, North Carolina State University, Raleigh, NC 27695-8202, USA
| | - Christopher Roland
- Department of Physics, North Carolina State University, Raleigh, NC 27695-8202, USA
| | - Celeste Sagui
- Department of Physics, North Carolina State University, Raleigh, NC 27695-8202, USA
| | - Keith Weninger
- Department of Physics, North Carolina State University, Raleigh, NC 27695-8202, USA
| |
Collapse
|
27
|
Volovikov EA, Davidenko AV, Lagarkova MA. Molecular Mechanisms of Spinocerebellar Ataxia Type 1. RUSS J GENET+ 2020. [DOI: 10.1134/s102279542002012x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
|
28
|
De Roeck A, De Coster W, Bossaerts L, Cacace R, De Pooter T, Van Dongen J, D’Hert S, De Rijk P, Strazisar M, Van Broeckhoven C, Sleegers K. NanoSatellite: accurate characterization of expanded tandem repeat length and sequence through whole genome long-read sequencing on PromethION. Genome Biol 2019; 20:239. [PMID: 31727106 PMCID: PMC6857246 DOI: 10.1186/s13059-019-1856-3] [Citation(s) in RCA: 39] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2019] [Accepted: 10/10/2019] [Indexed: 12/13/2022] Open
Abstract
Technological limitations have hindered the large-scale genetic investigation of tandem repeats in disease. We show that long-read sequencing with a single Oxford Nanopore Technologies PromethION flow cell per individual achieves 30× human genome coverage and enables accurate assessment of tandem repeats including the 10,000-bp Alzheimer's disease-associated ABCA7 VNTR. The Guppy "flip-flop" base caller and tandem-genotypes tandem repeat caller are efficient for large-scale tandem repeat assessment, but base calling and alignment challenges persist. We present NanoSatellite, which analyzes tandem repeats directly on electric current data and improves calling of GC-rich tandem repeats, expanded alleles, and motif interruptions.
Collapse
Affiliation(s)
- Arne De Roeck
- Neurodegenerative Brain Diseases Group, VIB Center for Molecular Neurology, University of Antwerp-CDE, Universiteitsplein 1, B-2610 Antwerp, Belgium
- Biomedical Sciences, University of Antwerp, Antwerp, Belgium
| | - Wouter De Coster
- Neurodegenerative Brain Diseases Group, VIB Center for Molecular Neurology, University of Antwerp-CDE, Universiteitsplein 1, B-2610 Antwerp, Belgium
- Biomedical Sciences, University of Antwerp, Antwerp, Belgium
| | - Liene Bossaerts
- Neurodegenerative Brain Diseases Group, VIB Center for Molecular Neurology, University of Antwerp-CDE, Universiteitsplein 1, B-2610 Antwerp, Belgium
- Biomedical Sciences, University of Antwerp, Antwerp, Belgium
| | - Rita Cacace
- Neurodegenerative Brain Diseases Group, VIB Center for Molecular Neurology, University of Antwerp-CDE, Universiteitsplein 1, B-2610 Antwerp, Belgium
- Biomedical Sciences, University of Antwerp, Antwerp, Belgium
| | - Tim De Pooter
- Neuromics Support Facility, Center for Molecular Neurology, VIB - University of Antwerp, Antwerp, Belgium
| | - Jasper Van Dongen
- Neurodegenerative Brain Diseases Group, VIB Center for Molecular Neurology, University of Antwerp-CDE, Universiteitsplein 1, B-2610 Antwerp, Belgium
- Biomedical Sciences, University of Antwerp, Antwerp, Belgium
| | - Svenn D’Hert
- Neuromics Support Facility, Center for Molecular Neurology, VIB - University of Antwerp, Antwerp, Belgium
| | - Peter De Rijk
- Neuromics Support Facility, Center for Molecular Neurology, VIB - University of Antwerp, Antwerp, Belgium
| | - Mojca Strazisar
- Neuromics Support Facility, Center for Molecular Neurology, VIB - University of Antwerp, Antwerp, Belgium
| | - Christine Van Broeckhoven
- Neurodegenerative Brain Diseases Group, VIB Center for Molecular Neurology, University of Antwerp-CDE, Universiteitsplein 1, B-2610 Antwerp, Belgium
- Biomedical Sciences, University of Antwerp, Antwerp, Belgium
| | - Kristel Sleegers
- Neurodegenerative Brain Diseases Group, VIB Center for Molecular Neurology, University of Antwerp-CDE, Universiteitsplein 1, B-2610 Antwerp, Belgium
- Biomedical Sciences, University of Antwerp, Antwerp, Belgium
| |
Collapse
|
29
|
Dolzhenko E, Deshpande V, Schlesinger F, Krusche P, Petrovski R, Chen S, Emig-Agius D, Gross A, Narzisi G, Bowman B, Scheffler K, van Vugt JJFA, French C, Sanchis-Juan A, Ibáñez K, Tucci A, Lajoie BR, Veldink JH, Raymond FL, Taft RJ, Bentley DR, Eberle MA. ExpansionHunter: a sequence-graph-based tool to analyze variation in short tandem repeat regions. BIOINFORMATICS (OXFORD, ENGLAND) 2019; 35:4754-4756. [PMID: 31134279 DOI: 10.1101/361162] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/10/2019] [Revised: 04/26/2019] [Accepted: 05/23/2019] [Indexed: 05/25/2023]
Abstract
SUMMARY We describe a novel computational method for genotyping repeats using sequence graphs. This method addresses the long-standing need to accurately genotype medically important loci containing repeats adjacent to other variants or imperfect DNA repeats such as polyalanine repeats. Here we introduce a new version of our repeat genotyping software, ExpansionHunter, that uses this method to perform targeted genotyping of a broad class of such loci. AVAILABILITY AND IMPLEMENTATION ExpansionHunter is implemented in C++ and is available under the Apache License Version 2.0. The source code, documentation, and Linux/macOS binaries are available at https://github.com/Illumina/ExpansionHunter/. SUPPLEMENTARY INFORMATION Supplementary data are available at Bioinformatics online.
Collapse
Affiliation(s)
| | | | | | - Peter Krusche
- Illumina Cambridge Ltd, Illumina Centre, 19 Granta Park, Great Abington, Cambridge CB21 6DF, UK
| | - Roman Petrovski
- Illumina Cambridge Ltd, Illumina Centre, 19 Granta Park, Great Abington, Cambridge CB21 6DF, UK
| | - Sai Chen
- Illumina Inc., San Diego, CA 92122, USA
| | | | | | - Giuseppe Narzisi
- Computational Biology, New York Genome Center, New York, NY 10013, USA
| | | | | | - Joke J F A van Vugt
- UMC Utrecht Brain Center, Utrecht University, 3508 AB Utrecht, The Netherlands
| | - Courtney French
- Department of Medical Genetics, NHS Blood and Transplant Centre, Cambridge, CB2 0PT, UK
| | - Alba Sanchis-Juan
- Department of Haematology, University of Cambridge, NHS Blood and Transplant Centre, Cambridge, CB2 0PT, UK
- NIHR BioResource, Cambridge University Hospitals NHS Foundation Trust, Cambridge Biomedical Campus, Cambridge, CB2 0QQ, UK
| | - Kristina Ibáñez
- Genomics England, Queen Mary University London, London EC1M 6BQ, UK
| | - Arianna Tucci
- Genomics England, Queen Mary University London, London EC1M 6BQ, UK
| | | | - Jan H Veldink
- UMC Utrecht Brain Center, Utrecht University, 3508 AB Utrecht, The Netherlands
| | - F Lucy Raymond
- Department of Medical Genetics, NHS Blood and Transplant Centre, Cambridge, CB2 0PT, UK
| | | | - David R Bentley
- Illumina Cambridge Ltd, Illumina Centre, 19 Granta Park, Great Abington, Cambridge CB21 6DF, UK
| | | |
Collapse
|
30
|
Mousavi N, Shleizer-Burko S, Yanicky R, Gymrek M. Profiling the genome-wide landscape of tandem repeat expansions. Nucleic Acids Res 2019; 47:e90. [PMID: 31194863 PMCID: PMC6735967 DOI: 10.1093/nar/gkz501] [Citation(s) in RCA: 123] [Impact Index Per Article: 24.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2019] [Revised: 05/15/2019] [Accepted: 05/28/2019] [Indexed: 12/15/2022] Open
Abstract
Tandem repeat (TR) expansions have been implicated in dozens of genetic diseases, including Huntington's Disease, Fragile X Syndrome, and hereditary ataxias. Furthermore, TRs have recently been implicated in a range of complex traits, including gene expression and cancer risk. While the human genome harbors hundreds of thousands of TRs, analysis of TR expansions has been mainly limited to known pathogenic loci. A major challenge is that expanded repeats are beyond the read length of most next-generation sequencing (NGS) datasets and are not profiled by existing genome-wide tools. We present GangSTR, a novel algorithm for genome-wide genotyping of both short and expanded TRs. GangSTR extracts information from paired-end reads into a unified model to estimate maximum likelihood TR lengths. We validate GangSTR on real and simulated data and show that GangSTR outperforms alternative methods in both accuracy and speed. We apply GangSTR to a deeply sequenced trio to profile the landscape of TR expansions in a healthy family and validate novel expansions using orthogonal technologies. Our analysis reveals that healthy individuals harbor dozens of long TR alleles not captured by current genome-wide methods. GangSTR will likely enable discovery of novel disease-associated variants not currently accessible from NGS.
Collapse
Affiliation(s)
- Nima Mousavi
- Department of Electrical and Computer Engineering, University of California San Diego, 9500 Gilman Drive, MC 0639, La Jolla, CA 92093, USA
| | - Sharona Shleizer-Burko
- Department of Medicine, University of California San Diego, 9500 Gilman Drive, MC 0639, La Jolla, CA 92093, USA
| | - Richard Yanicky
- Department of Medicine, University of California San Diego, 9500 Gilman Drive, MC 0639, La Jolla, CA 92093, USA
| | - Melissa Gymrek
- Department of Medicine, University of California San Diego, 9500 Gilman Drive, MC 0639, La Jolla, CA 92093, USA
- Department of Computer Science and Engineering, University of California San Diego, 9500 Gilman Drive, MC 0639, La Jolla, CA 92093, USA
| |
Collapse
|
31
|
De Coster W, Van Broeckhoven C. Newest Methods for Detecting Structural Variations. Trends Biotechnol 2019; 37:973-982. [DOI: 10.1016/j.tibtech.2019.02.003] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2018] [Revised: 02/08/2019] [Accepted: 02/11/2019] [Indexed: 01/28/2023]
|
32
|
Hafford-Tear NJ, Tsai YC, Sadan AN, Sanchez-Pintado B, Zarouchlioti C, Maher GJ, Liskova P, Tuft SJ, Hardcastle AJ, Clark TA, Davidson AE. CRISPR/Cas9-targeted enrichment and long-read sequencing of the Fuchs endothelial corneal dystrophy-associated TCF4 triplet repeat. Genet Med 2019; 21:2092-2102. [PMID: 30733599 PMCID: PMC6752322 DOI: 10.1038/s41436-019-0453-x] [Citation(s) in RCA: 41] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2018] [Accepted: 01/24/2019] [Indexed: 12/15/2022] Open
Abstract
PURPOSE To demonstrate the utility of an amplification-free long-read sequencing method to characterize the Fuchs endothelial corneal dystrophy (FECD)-associated intronic TCF4 triplet repeat (CTG18.1). METHODS We applied an amplification-free method, utilizing the CRISPR/Cas9 system, in combination with PacBio single-molecule real-time (SMRT) long-read sequencing, to study CTG18.1. FECD patient samples displaying a diverse range of CTG18.1 allele lengths and zygosity status (n = 11) were analyzed. A robust data analysis pipeline was developed to effectively filter, align, and interrogate CTG18.1-specific reads. All results were compared with conventional polymerase chain reaction (PCR)-based fragment analysis. RESULTS CRISPR-guided SMRT sequencing of CTG18.1 provided accurate genotyping information for all samples and phasing was possible for 18/22 alleles sequenced. Repeat length instability was observed for all expanded (≥50 repeats) phased CTG18.1 alleles analyzed. Furthermore, higher levels of repeat instability were associated with increased CTG18.1 allele length (mode length ≥91 repeats) indicating that expanded alleles behave dynamically. CONCLUSION CRISPR-guided SMRT sequencing of CTG18.1 has revealed novel insights into CTG18.1 length instability. Furthermore, this study provides a framework to improve the molecular diagnostic accuracy for CTG18.1-mediated FECD, which we anticipate will become increasingly important as gene-directed therapies are developed for this common age-related and sight threatening disease.
Collapse
Affiliation(s)
| | | | | | | | | | - Geoffrey J Maher
- Clinical Genetics Group, MRC Weatherall Institute of Molecular Medicine, University of Oxford, John Radcliffe Hospital, Oxford, UK
| | - Petra Liskova
- UCL Institute of Ophthalmology, London, UK
- Department of Ophthalmology, First Faculty of Medicine, Charles University and General University Hospital in Prague, Prague, Czech Republic
| | - Stephen J Tuft
- UCL Institute of Ophthalmology, London, UK
- Moorfields Eye Hospital, London, UK
| | | | | | | |
Collapse
|
33
|
Wieben ED, Aleff RA, Basu S, Sarangi V, Bowman B, McLaughlin IJ, Mills JR, Butz ML, Highsmith EW, Ida CM, Ekholm JM, Baratz KH, Fautsch MP. Amplification-free long-read sequencing of TCF4 expanded trinucleotide repeats in Fuchs Endothelial Corneal Dystrophy. PLoS One 2019; 14:e0219446. [PMID: 31276570 PMCID: PMC6611681 DOI: 10.1371/journal.pone.0219446] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2019] [Accepted: 06/24/2019] [Indexed: 11/18/2022] Open
Abstract
Amplification of a CAG trinucleotide motif (CTG18.1) within the TCF4 gene has been strongly associated with Fuchs Endothelial Corneal Dystrophy (FECD). Nevertheless, a small minority of clinically unaffected elderly patients who have expanded CTG18.1 sequences have been identified. To test the hypothesis that the CAG expansions in these patients are protected from FECD because they have interruptions within the CAG repeats, we utilized a combination of an amplification-free, long-read sequencing method and a new target-enrichment sequence analysis tool developed by Pacific Biosciences to interrogate the sequence structure of expanded repeats. The sequencing was successful in identifying a previously described interruption within an unexpanded allele and provided sequence data on expanded alleles greater than 2000 bases in length. The data revealed considerable heterogeneity in the size distribution of expanded repeats within each patient. Detailed analysis of the long sequence reads did not reveal any instances of interruptions to the expanded CAG repeats, but did reveal novel variants within the AGG repeats that flank the CAG repeats in two of the five samples from clinically unaffected patients with expansions. This first examination of the sequence structure of CAG repeats in CTG18.1 suggests that factors other than interruptions to the repeat structure account for the absence of disease in some elderly patients with repeat expansions in the TCF4 gene.
Collapse
Affiliation(s)
- Eric D. Wieben
- Department of Biochemistry and Molecular Biology, Mayo Clinic, Rochester, Minnesota, United States of America
| | - Ross A. Aleff
- Department of Biochemistry and Molecular Biology, Mayo Clinic, Rochester, Minnesota, United States of America
| | - Shubham Basu
- Division of Biostatistics and Bioinformatics and Department of Health Sciences Research, Mayo Clinic, Rochester, Minnesota, United States of America
| | - Vivekananda Sarangi
- Division of Biostatistics and Bioinformatics and Department of Health Sciences Research, Mayo Clinic, Rochester, Minnesota, United States of America
| | - Brett Bowman
- Pacific Biosciences of California, Inc., Menlo Park, CA, United States of America
| | - Ian J. McLaughlin
- Pacific Biosciences of California, Inc., Menlo Park, CA, United States of America
| | - John R. Mills
- Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, MN, United States of America
| | - Malinda L. Butz
- Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, MN, United States of America
| | - Edward W. Highsmith
- Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, MN, United States of America
| | - Cristiane M. Ida
- Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, MN, United States of America
| | - Jenny M. Ekholm
- Pacific Biosciences of California, Inc., Menlo Park, CA, United States of America
| | - Keith H. Baratz
- Department of Ophthalmology, Mayo Clinic, Rochester, Minnesota, United States of America
| | - Michael P. Fautsch
- Department of Ophthalmology, Mayo Clinic, Rochester, Minnesota, United States of America
| |
Collapse
|
34
|
Rafehi H, Szmulewicz DJ, Bennett MF, Sobreira NLM, Pope K, Smith KR, Gillies G, Diakumis P, Dolzhenko E, Eberle MA, Barcina MG, Breen DP, Chancellor AM, Cremer PD, Delatycki MB, Fogel BL, Hackett A, Halmagyi GM, Kapetanovic S, Lang A, Mossman S, Mu W, Patrikios P, Perlman SL, Rosemergy I, Storey E, Watson SRD, Wilson MA, Zee DS, Valle D, Amor DJ, Bahlo M, Lockhart PJ. Bioinformatics-Based Identification of Expanded Repeats: A Non-reference Intronic Pentamer Expansion in RFC1 Causes CANVAS. Am J Hum Genet 2019; 105:151-165. [PMID: 31230722 PMCID: PMC6612533 DOI: 10.1016/j.ajhg.2019.05.016] [Citation(s) in RCA: 146] [Impact Index Per Article: 29.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2019] [Accepted: 05/21/2019] [Indexed: 01/28/2023] Open
Abstract
Genomic technologies such as next-generation sequencing (NGS) are revolutionizing molecular diagnostics and clinical medicine. However, these approaches have proven inefficient at identifying pathogenic repeat expansions. Here, we apply a collection of bioinformatics tools that can be utilized to identify either known or novel expanded repeat sequences in NGS data. We performed genetic studies of a cohort of 35 individuals from 22 families with a clinical diagnosis of cerebellar ataxia with neuropathy and bilateral vestibular areflexia syndrome (CANVAS). Analysis of whole-genome sequence (WGS) data with five independent algorithms identified a recessively inherited intronic repeat expansion [(AAGGG)exp] in the gene encoding Replication Factor C1 (RFC1). This motif, not reported in the reference sequence, localized to an Alu element and replaced the reference (AAAAG)11 short tandem repeat. Genetic analyses confirmed the pathogenic expansion in 18 of 22 CANVAS-affected families and identified a core ancestral haplotype, estimated to have arisen in Europe more than twenty-five thousand years ago. WGS of the four RFC1-negative CANVAS-affected families identified plausible variants in three, with genomic re-diagnosis of SCA3, spastic ataxia of the Charlevoix-Saguenay type, and SCA45. This study identified the genetic basis of CANVAS and demonstrated that these improved bioinformatics tools increase the diagnostic utility of WGS to determine the genetic basis of a heterogeneous group of clinically overlapping neurogenetic disorders.
Collapse
Affiliation(s)
- Haloom Rafehi
- Population Health and Immunity Division, The Walter and Eliza Hall Institute of Medical Research, 1G Royal Parade, Parkville, VIC 3052, Australia; Department of Medical Biology, University of Melbourne, 1G Royal Parade, Parkville, VIC 3052, Australia
| | - David J Szmulewicz
- Cerebellar Ataxia Clinic, Neuroscience Department, Alfred Health, Melbourne, VIC 3004, Australia; Balance Disorders and Ataxia Service, Royal Victorian Eye & Ear Hospital, East Melbourne, VIC 3002, Australia
| | - Mark F Bennett
- Population Health and Immunity Division, The Walter and Eliza Hall Institute of Medical Research, 1G Royal Parade, Parkville, VIC 3052, Australia; Department of Medical Biology, University of Melbourne, 1G Royal Parade, Parkville, VIC 3052, Australia; Epilepsy Research Centre, Department of Medicine, University of Melbourne, Austin Health, 245 Burgundy Street, Heidelberg, VIC 3084, Australia
| | - Nara L M Sobreira
- McKusick-Nathans Institute of Genetic Medicine, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Kate Pope
- Bruce Lefroy Centre, Murdoch Children's Research Institute, Flemington Rd, Parkville, VIC 3052, Australia
| | - Katherine R Smith
- Population Health and Immunity Division, The Walter and Eliza Hall Institute of Medical Research, 1G Royal Parade, Parkville, VIC 3052, Australia
| | - Greta Gillies
- Bruce Lefroy Centre, Murdoch Children's Research Institute, Flemington Rd, Parkville, VIC 3052, Australia
| | - Peter Diakumis
- University of Melbourne Centre for Cancer Research, Victorian Comprehensive Cancer Centre, 305 Grattan Street, Melbourne, VIC 3000, Australia
| | - Egor Dolzhenko
- Illumina Inc, 5200 Illumina Way, San Diego, CA 92122, USA
| | | | - María García Barcina
- Genetic Unit, Basurto University Hospital, OSI Bilbao-Basurto, avenida Montevideo 18, 48013 Bilbao, Spain
| | - David P Breen
- Centre for Clinical Brain Sciences, University of Edinburgh, Edinburgh EH16 4SB, Scotland; Anne Rowling Regenerative Neurology Clinic, University of Edinburgh, Edinburgh EH16 4SB, Scotland; Usher Institute of Population Health Sciences and Informatics, University of Edinburgh, Edinburgh EH16 4UX, Scotland
| | - Andrew M Chancellor
- Department of Neurology, Tauranga Hospital, Private Bag, Cameron Road, Tauranga 3171, New Zealand
| | - Phillip D Cremer
- University of Sydney, Camperdown, NSW 2006, Australia; Royal North Shore Hospital, Pacific Hwy, St Leonards, NSW 2065, Australia
| | - Martin B Delatycki
- Bruce Lefroy Centre, Murdoch Children's Research Institute, Flemington Rd, Parkville, VIC 3052, Australia; Department of Paediatrics, University of Melbourne, Royal Children's Hospital, Flemington Rd, Parkville, VIC 3052, Australia
| | - Brent L Fogel
- Departments of Neurology and Human Genetics, David Geffen School of Medicine, University of California, Los Angeles, CA 90095, USA
| | - Anna Hackett
- Hunter Genetics, Hunter New England Health Service, Waratah, Newcastle, NSW 2300, Australia; University of Newcastle, Newcastle, NSW 2300, Australia
| | - G Michael Halmagyi
- Neurology Department, Royal Prince Alfred Hospital, Camperdown, NSW 2050, Australia; Central Clinical School, University of Sydney, Camperdown, NSW 2050, Australia
| | - Solange Kapetanovic
- Servicio de Neurología, Hospital de Basurto, Avenida de Montevideo 18, 48013 Bilbao, Bizkaia, Spain
| | - Anthony Lang
- Edmond J. Safra Program in Parkinson disease and the Morton and Gloria Shulman Movement Disorders Clinic, Toronto Western Hospital, Toronto, ON M5T 2S8, Canada; Department of Medicine, Division of Neurology, University Health Network and the University of Toronto, Toronto, ON M5T 2S8, Canada
| | - Stuart Mossman
- Department of Neurology, Wellington Hospital, Wellington 6021, New Zealand
| | - Weiyi Mu
- McKusick-Nathans Institute of Genetic Medicine, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | | | - Susan L Perlman
- Department of Neurology, David Geffen School of Medicine, University of California, Los Angeles, CA 90095, USA
| | - Ian Rosemergy
- Department of Neurology, Wellington Hospital, Newtown, Wellington 6021, New Zealand
| | - Elsdon Storey
- Department of Neuroscience, Central Clinical School, Monash University, Alfred Hospital Campus, Commercial Road, Melbourne, VIC 3004, Australia
| | - Shaun R D Watson
- Institute of Neurological Sciences, Prince of Wales Hospital, Randwick, NSW 2031, Australia
| | - Michael A Wilson
- Bruce Lefroy Centre, Murdoch Children's Research Institute, Flemington Rd, Parkville, VIC 3052, Australia
| | - David S Zee
- Department of Neurology, Johns Hopkins Hospital, Baltimore, MD 21287, USA
| | - David Valle
- McKusick-Nathans Institute of Genetic Medicine, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - David J Amor
- Bruce Lefroy Centre, Murdoch Children's Research Institute, Flemington Rd, Parkville, VIC 3052, Australia; Department of Paediatrics, University of Melbourne, Royal Children's Hospital, Flemington Rd, Parkville, VIC 3052, Australia
| | - Melanie Bahlo
- Population Health and Immunity Division, The Walter and Eliza Hall Institute of Medical Research, 1G Royal Parade, Parkville, VIC 3052, Australia; Department of Medical Biology, University of Melbourne, 1G Royal Parade, Parkville, VIC 3052, Australia
| | - Paul J Lockhart
- Bruce Lefroy Centre, Murdoch Children's Research Institute, Flemington Rd, Parkville, VIC 3052, Australia; Department of Paediatrics, University of Melbourne, Royal Children's Hospital, Flemington Rd, Parkville, VIC 3052, Australia.
| |
Collapse
|
35
|
Rohrback S, Siddoway B, Liu CS, Chun J. Genomic mosaicism in the developing and adult brain. Dev Neurobiol 2018; 78:1026-1048. [PMID: 30027562 PMCID: PMC6214721 DOI: 10.1002/dneu.22626] [Citation(s) in RCA: 68] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2018] [Revised: 05/31/2018] [Accepted: 06/01/2018] [Indexed: 12/18/2022]
Abstract
Since the discovery of DNA, the normal developing and functioning brain has been assumed to be composed of cells with identical genomes, which remains the dominant view even today. However, this pervasive assumption is incorrect, as proven by increasing numbers of reports within the last 20 years that have identified multiple forms of somatically produced genomic mosaicism (GM), wherein brain cells-especially neurons-from a single individual show diverse alterations in DNA, distinct from the germline. Critically, these changes alter the actual DNA nucleotide sequences-in contrast to epigenetic mechanisms-and almost certainly contribute to the remarkably diverse phenotypes of single brain cells, including single-cell transcriptomic profiles. Here, we review the history of GM within the normal brain, including its major forms, initiating mechanisms, and possible functions. GM forms include aneuploidies and aneusomies, smaller copy number variations (CNVs), long interspersed nuclear element type 1 (LINE1) repeat elements, and single nucleotide variations (SNVs), as well as DNA content variation (DCV) that reflects all forms of GM with greatest coverage of large, brain cell populations. In addition, technical considerations are examined, along with relationships among GM forms and multiple brain diseases. GM affecting genes and loci within the brain contrast with current neural discovery approaches that rely on sequencing nonbrain DNA (e.g., genome-wide association studies (GWAS)). Increasing knowledge of neural GM has implications for mechanisms of development, diversity, and function, as well as understanding diseases, particularly considering the overwhelming prevalence of sporadic brain diseases that are unlinked to germline mutations. © 2018 The Authors. Developmental Neurobiology Published by Wiley Periodicals, Inc. Develop Neurobiol, 2018.
Collapse
Affiliation(s)
- Suzanne Rohrback
- Biomedical Sciences Graduate Program, School of MedicineUniversity of California San DiegoLa JollaCalifornia92093
- Sanford Burnham Prebys Medical Discovery InstituteLa JollaCalifornia
- Present address:
Illumina, Inc.San DiegoCA 92122USA
| | - Benjamin Siddoway
- Sanford Burnham Prebys Medical Discovery InstituteLa JollaCalifornia
| | - Christine S. Liu
- Biomedical Sciences Graduate Program, School of MedicineUniversity of California San DiegoLa JollaCalifornia92093
- Sanford Burnham Prebys Medical Discovery InstituteLa JollaCalifornia
| | - Jerold Chun
- Sanford Burnham Prebys Medical Discovery InstituteLa JollaCalifornia
| |
Collapse
|
36
|
Ebbert MTW, Farrugia SL, Sens JP, Jansen-West K, Gendron TF, Prudencio M, McLaughlin IJ, Bowman B, Seetin M, DeJesus-Hernandez M, Jackson J, Brown PH, Dickson DW, van Blitterswijk M, Rademakers R, Petrucelli L, Fryer JD. Long-read sequencing across the C9orf72 'GGGGCC' repeat expansion: implications for clinical use and genetic discovery efforts in human disease. Mol Neurodegener 2018; 13:46. [PMID: 30126445 PMCID: PMC6102925 DOI: 10.1186/s13024-018-0274-4] [Citation(s) in RCA: 70] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2018] [Accepted: 07/20/2018] [Indexed: 12/12/2022] Open
Abstract
BACKGROUND Many neurodegenerative diseases are caused by nucleotide repeat expansions, but most expansions, like the C9orf72 'GGGGCC' (G4C2) repeat that causes approximately 5-7% of all amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD) cases, are too long to sequence using short-read sequencing technologies. It is unclear whether long-read sequencing technologies can traverse these long, challenging repeat expansions. Here, we demonstrate that two long-read sequencing technologies, Pacific Biosciences' (PacBio) and Oxford Nanopore Technologies' (ONT), can sequence through disease-causing repeats cloned into plasmids, including the FTD/ALS-causing G4C2 repeat expansion. We also report the first long-read sequencing data characterizing the C9orf72 G4C2 repeat expansion at the nucleotide level in two symptomatic expansion carriers using PacBio whole-genome sequencing and a no-amplification (No-Amp) targeted approach based on CRISPR/Cas9. RESULTS Both the PacBio and ONT platforms successfully sequenced through the repeat expansions in plasmids. Throughput on the MinION was a challenge for whole-genome sequencing; we were unable to attain reads covering the human C9orf72 repeat expansion using 15 flow cells. We obtained 8× coverage across the C9orf72 locus using the PacBio Sequel, accurately reporting the unexpanded allele at eight repeats, and reading through the entire expansion with 1324 repeats (7941 nucleotides). Using the No-Amp targeted approach, we attained > 800× coverage and were able to identify the unexpanded allele, closely estimate expansion size, and assess nucleotide content in a single experiment. We estimate the individual's repeat region was > 99% G4C2 content, though we cannot rule out small interruptions. CONCLUSIONS Our findings indicate that long-read sequencing is well suited to characterizing known repeat expansions, and for discovering new disease-causing, disease-modifying, or risk-modifying repeat expansions that have gone undetected with conventional short-read sequencing. The PacBio No-Amp targeted approach may have future potential in clinical and genetic counseling environments. Larger and deeper long-read sequencing studies in C9orf72 expansion carriers will be important to determine heterogeneity and whether the repeats are interrupted by non-G4C2 content, potentially mitigating or modifying disease course or age of onset, as interruptions are known to do in other repeat-expansion disorders. These results have broad implications across all diseases where the genetic etiology remains unclear.
Collapse
Affiliation(s)
- Mark T. W. Ebbert
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL 32224 USA
- Mayo Graduate School, Mayo Clinic, Rochester, MN 55905 USA
| | | | - Jonathon P. Sens
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL 32224 USA
- Mayo Graduate School, Mayo Clinic, Rochester, MN 55905 USA
| | | | - Tania F. Gendron
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL 32224 USA
| | | | | | | | | | | | - Jazmyne Jackson
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL 32224 USA
| | | | | | | | - Rosa Rademakers
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL 32224 USA
| | - Leonard Petrucelli
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL 32224 USA
- Mayo Graduate School, Mayo Clinic, Rochester, MN 55905 USA
| | - John D. Fryer
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL 32224 USA
- Mayo Graduate School, Mayo Clinic, Rochester, MN 55905 USA
| |
Collapse
|
37
|
Validation of a Long-Read PCR Assay for Sensitive Detection and Sizing of C9orf72 Hexanucleotide Repeat Expansions. J Mol Diagn 2018; 20:871-882. [PMID: 30138726 DOI: 10.1016/j.jmoldx.2018.07.001] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2018] [Revised: 06/09/2018] [Accepted: 07/09/2018] [Indexed: 12/13/2022] Open
Abstract
A hexanucleotide GGGGCC repeat expansion in C9orf72 is the most common genetic cause of amyotrophic lateral sclerosis and frontotemporal degeneration. Accurate determination and quantitation of the repeat length is critical in both clinical and research settings. However, because of the complexity of the C9orf72 expansion with high GC content, large size of repeats, and high rate of insertions/deletions (indels) and sequence variations in the flanking regions, molecular genetic analysis of the locus is challenging. To improve the performance characteristics for clinical testing, we evaluated a commercially available long-read C9orf72 PCR assay for research use only, AmplideX PCR/CE C9orf72 assay (AmplideX-C9), and compared its performance with our existing laboratory-developed C9orf72 expansion procedure. Overall, in comparison to the laboratory-developed C9orf72 expansion procedure, AmplideX-C9 demonstrated a more efficient workflow, greater PCR efficiency for sizing of repeat expansions, and improved peak amplitude with lower DNA input and higher analytic sensitivity. This, in turn, permitted detection of indels in the 3' downstream of the repeat expansion region in expanded alleles, showed a higher success rate with formalin-fixed, paraffin-embedded tissue specimens, and facilitated the assessment of repeat mosaicism. In summary, AmplideX-C9 will not only help to improve clinical testing for C9orf72-associated amyotrophic lateral sclerosis and frontotemporal degeneration but will also be a valuable research tool to better characterize the complexity of expansions and study the effects of indels/sequence variations in the flanking region.
Collapse
|
38
|
Pérez Ortiz JM, Mollema N, Toker N, Adamski CJ, O'Callaghan B, Duvick L, Friedrich J, Walters MA, Strasser J, Hawkinson JE, Zoghbi HY, Henzler C, Orr HT, Lagalwar S. Reduction of protein kinase A-mediated phosphorylation of ATXN1-S776 in Purkinje cells delays onset of Ataxia in a SCA1 mouse model. Neurobiol Dis 2018; 116:93-105. [PMID: 29758256 DOI: 10.1016/j.nbd.2018.05.002] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2017] [Revised: 04/17/2018] [Accepted: 05/09/2018] [Indexed: 12/27/2022] Open
Abstract
Spinocerebellar ataxia type 1 (SCA1) is a polyglutamine (polyQ) repeat neurodegenerative disease in which a primary site of pathogenesis are cerebellar Purkinje cells. In addition to polyQ expansion of ataxin-1 protein (ATXN1), phosphorylation of ATXN1 at the serine 776 residue (ATXN1-pS776) plays a significant role in protein toxicity. Utilizing a biochemical approach, pharmacological agents and cell-based assays, including SCA1 patient iPSC-derived neurons, we examine the role of Protein Kinase A (PKA) as an effector of ATXN1-S776 phosphorylation. We further examine the implications of PKA-mediated phosphorylation at ATXN1-S776 on SCA1 through genetic manipulation of the PKA catalytic subunit Cα in Pcp2-ATXN1[82Q] mice. Here we show that pharmacologic inhibition of S776 phosphorylation in transfected cells and SCA1 patient iPSC-derived neuronal cells lead to a decrease in ATXN1. In vivo, reduction of PKA-mediated ATXN1-pS776 results in enhanced degradation of ATXN1 and improved cerebellar-dependent motor performance. These results provide evidence that PKA is a biologically important kinase for ATXN1-pS776 in cerebellar Purkinje cells.
Collapse
Affiliation(s)
- Judit M Pérez Ortiz
- Institute for Translational Neuroscience, University of Minnesota, Minneapolis, MN, United States; Graduate Program in Neuroscience, University of Minnesota, Minneapolis, MN, United States
| | - Nissa Mollema
- Institute for Translational Neuroscience, University of Minnesota, Minneapolis, MN, United States; Department of Laboratory Medicine and Pathology, University of Minnesota, Minneapolis, MN, United States
| | - Nicholas Toker
- Skidmore College Neuroscience Program, Saratoga Springs, NY, United States
| | - Carolyn J Adamski
- Jan and Dan Duncan Neurological Research Institute at Texas Children's Hospital, and Department of Molecular and Human Genetics, Howard Hughes Medical Institute, Baylor College of Medicine, Houston, TX, United States
| | - Brennon O'Callaghan
- Institute for Translational Neuroscience, University of Minnesota, Minneapolis, MN, United States; Department of Laboratory Medicine and Pathology, University of Minnesota, Minneapolis, MN, United States
| | - Lisa Duvick
- Institute for Translational Neuroscience, University of Minnesota, Minneapolis, MN, United States; Department of Laboratory Medicine and Pathology, University of Minnesota, Minneapolis, MN, United States
| | - Jillian Friedrich
- Institute for Translational Neuroscience, University of Minnesota, Minneapolis, MN, United States; Department of Laboratory Medicine and Pathology, University of Minnesota, Minneapolis, MN, United States
| | - Michael A Walters
- Department of Medicinal Chemistry, Institute for Therapeutics Discovery and Development, University of Minnesota, United States
| | - Jessica Strasser
- Department of Medicinal Chemistry, Institute for Therapeutics Discovery and Development, University of Minnesota, United States
| | - Jon E Hawkinson
- Department of Medicinal Chemistry, Institute for Therapeutics Discovery and Development, University of Minnesota, United States
| | - Huda Y Zoghbi
- Jan and Dan Duncan Neurological Research Institute at Texas Children's Hospital, and Department of Molecular and Human Genetics, Howard Hughes Medical Institute, Baylor College of Medicine, Houston, TX, United States
| | - Christine Henzler
- RISS Bioinformatics, Minnesota Supercomputing Institute, University of Minnesota, Minneapolis, MN, United States
| | - Harry T Orr
- Institute for Translational Neuroscience, University of Minnesota, Minneapolis, MN, United States; Department of Laboratory Medicine and Pathology, University of Minnesota, Minneapolis, MN, United States.
| | - Sarita Lagalwar
- Institute for Translational Neuroscience, University of Minnesota, Minneapolis, MN, United States; Department of Laboratory Medicine and Pathology, University of Minnesota, Minneapolis, MN, United States; Skidmore College Neuroscience Program, Saratoga Springs, NY, United States.
| |
Collapse
|
39
|
Mier P, Andrade-Navarro MA. Glutamine Codon Usage and polyQ Evolution in Primates Depend on the Q Stretch Length. Genome Biol Evol 2018; 10:816-825. [PMID: 29608721 PMCID: PMC5841385 DOI: 10.1093/gbe/evy046] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/19/2018] [Indexed: 12/16/2022] Open
Abstract
Amino acid usage in a proteome depends mostly on its taxonomy, as it does the codon usage in transcriptomes. Here, we explore the level of variation in the codon usage of a specific amino acid, glutamine, in relation to the number of consecutive glutamine residues. We show that CAG triplets are consistently more abundant in short glutamine homorepeats (polyQ, four to eight residues) than in shorter glutamine stretches (one to three residues), leading to the evolutionary growth of the repeat region in a CAG-dependent manner. The length of orthologous polyQ regions is mostly stable in primates, particularly the short ones. Interestingly, given a short polyQ the CAG usage is higher in unstable-in-length orthologous polyQ regions. This indicates that CAG triplets produce the necessary instability for a glutamine stretch to grow. Proteins related to polyQ-associated diseases behave in a more extreme way, with longer glutamine stretches in human and evolutionarily closer nonhuman primates, and an overall higher CAG usage. In the light of our results, we suggest an evolutionary model to explain the glutamine codon usage in polyQ regions.
Collapse
Affiliation(s)
- Pablo Mier
- Faculty of Biology, Johannes Gutenberg University Mainz, Germany
- Institute of Molecular Biology, Mainz, Germany
| | - Miguel A Andrade-Navarro
- Faculty of Biology, Johannes Gutenberg University Mainz, Germany
- Institute of Molecular Biology, Mainz, Germany
| |
Collapse
|
40
|
Cagnoli C, Brussino A, Mancini C, Ferrone M, Orsi L, Salmin P, Pappi P, Giorgio E, Pozzi E, Cavalieri S, Di Gregorio E, Ferrero M, Filla A, De Michele G, Gellera C, Mariotti C, Nethisinghe S, Giunti P, Stevanin G, Brusco A. Spinocerebellar Ataxia Tethering PCR: A Rapid Genetic Test for the Diagnosis of Spinocerebellar Ataxia Types 1, 2, 3, 6, and 7 by PCR and Capillary Electrophoresis. J Mol Diagn 2018; 20:289-297. [PMID: 29462666 DOI: 10.1016/j.jmoldx.2017.12.006] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2017] [Revised: 11/17/2017] [Accepted: 12/19/2017] [Indexed: 12/14/2022] Open
Abstract
Spinocerebellar ataxia (SCA) types 1, 2, 3, 6, and 7, associated with a (CAG)n repeat expansion in coding sequences, are the most prevalent autosomal dominant ataxias worldwide (approximately 60% of the cases). In addition, the phenotype of SCA2 expansions has been now extended to Parkinson disease and amyotrophic lateral sclerosis. Their diagnosis is currently based on a PCR to identify small expanded alleles, followed by a second-level test whenever a false normal homozygous or a CAT interruption in SCA1 needs to be verified. Next-generation sequencing still does not allow efficient detection of these repeats. Here, we show the efficacy of a novel, rapid, and cost-effective method to identify and size pathogenic expansions in SCA1, 2, 3, 6, and 7 and recognize large alleles or interruptions without a second-level test. Twenty-five healthy controls and 33 expansion carriers were analyzed: alleles migrated consistently in different PCRs and capillary runs, and homozygous individuals were always distinguishable from heterozygous carriers of both common and large (>100 repeats) pathogenic CAG expansions. Repeat number could be calculated counting the number of peaks, except for the largest SCA2 and SCA7 alleles. Interruptions in SCA1 were always visible. Overall, our method allows a simpler, cost-effective, and sensibly faster SCA diagnostic protocol compared with the standard technique and to the still unadapted next-generation sequencing.
Collapse
Affiliation(s)
- Claudia Cagnoli
- Department of Medical Sciences, University of Turin, Turin, Italy
| | | | - Cecilia Mancini
- Department of Medical Sciences, University of Turin, Turin, Italy
| | - Marina Ferrone
- Department of Medical Sciences, University of Turin, Turin, Italy; Medical Genetics Unit, Città della Salute e della Scienza University Hospital, Turin, Italy
| | - Laura Orsi
- Department of Laboratory Medicine, and the Neurologic Division I, Department of Neuroscience and Mental Health, Città della Salute e della Scienza University Hospital, Turin, Italy
| | - Paola Salmin
- Medical Genetics Unit, Città della Salute e della Scienza University Hospital, Turin, Italy
| | - Patrizia Pappi
- Medical Genetics Unit, Città della Salute e della Scienza University Hospital, Turin, Italy
| | - Elisa Giorgio
- Department of Medical Sciences, University of Turin, Turin, Italy
| | - Elisa Pozzi
- Department of Medical Sciences, University of Turin, Turin, Italy
| | - Simona Cavalieri
- Department of Medical Sciences, University of Turin, Turin, Italy
| | | | - Marta Ferrero
- Department of Medical Sciences, University of Turin, Turin, Italy
| | - Alessandro Filla
- Department of Neurosciences, Odontostomatological and Reproductive Sciences, University Federico II, Naples, Italy
| | - Giuseppe De Michele
- Department of Neurosciences, Odontostomatological and Reproductive Sciences, University Federico II, Naples, Italy
| | - Cinzia Gellera
- Unit of Genetics of Neurodegenerative and Metabolic Diseases, Fondazione IRCCS Carlo Besta Neurological Institute, Milan, Italy
| | - Caterina Mariotti
- Unit of Genetics of Neurodegenerative and Metabolic Diseases, Fondazione IRCCS Carlo Besta Neurological Institute, Milan, Italy
| | - Suran Nethisinghe
- Ataxia Centre, Department of Molecular Neuroscience, Institute of Neurology, University College London, London, United Kingdom
| | - Paola Giunti
- Ataxia Centre, Department of Molecular Neuroscience, Institute of Neurology, University College London, London, United Kingdom
| | - Giovanni Stevanin
- INSERM, U 1127, Institut du Cerveau et de la Moelle epinière, Paris, France; Centre National de la Recherche Scientifique UMR 7225, Paris, France; UMRS 1127, Université Pierre et Marie Curie (Paris 06), Sorbonne Universités, Paris, France; Ecole Pratique des Hautes Etudes, PSL Research University, Paris, France; Centre de Référence de Neurogénétique, Hôpital de la Pitié-Salpêtrière, Assistance Publique - Hôpitaux de Paris, Paris, France
| | - Alfredo Brusco
- Department of Medical Sciences, University of Turin, Turin, Italy; Medical Genetics Unit, Città della Salute e della Scienza University Hospital, Turin, Italy.
| |
Collapse
|
41
|
Hashimoto M, Ho G, Takamatsu Y, Wada R, Sugama S, Takenouchi T, Masliah E, Waragai M. Possible Role of the Polyglutamine Elongation in Evolution of Amyloid-Related Evolvability. J Huntingtons Dis 2018; 7:297-307. [PMID: 30372687 PMCID: PMC6294593 DOI: 10.3233/jhd-180309] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The polyglutamine (polyQ) diseases, such as Huntington's disease and the spinocerebellar ataxias, are characterized by the accumulation of elongated polyQ sequences (epolyQ) and mostly occur during midlife. Considering that polyQ disorders have not been selected out in evolution, there might be important physiological functions of epolyQ during development and/or reproduction. In a similar context, the physiological functions of neurodegeneration-associated amyloidogenic proteins (APs), such as β-amyloid in Alzheimer's disease and α-synuclein in Parkinson's disease, remain elusive. In this regard, we recently proposed that evolvability for coping with diverse stressors in the brain, which is beneficial for offspring, might be relevant to the physiological functions of APs. Given analogous properties of APs and epolyQ in terms of neurotoxic amyloid-fibril formation, the objective of this paper is to determine whether evolvability could also be applied to the physiological functions of epolyQ. Indeed, APs and epolyQ are similar in many ways, including functional redundancy of non-amyloidogenic homologues, hormesis conferred by the heterogeneity of the stress-induced protein aggregates, the transgenerational prion-like transmission of the protein aggregates via germ cells, and the antagonistic pleiotropy relationship between evolvability and neurodegenerative disease. Given that epolyQ is widely expressed from microorganisms to human brain, whereas APs are only identified in vertebrates, evolvability of epolyQ is considered to be much more primitive compared to those of APs during evolution. Collectively, epolyQ may be not only be important in the pathophysiology of polyQ diseases, but also in the evolution of amyloid-related evolvability.
Collapse
Affiliation(s)
- Makoto Hashimoto
- Tokyo Metropolitan Institute of Medical Science, Kamikitazawa, Setagaya-ku, Tokyo, Japan
| | - Gilbert Ho
- PCND Neuroscience Research Institute, Poway, CA, USA
| | - Yoshiki Takamatsu
- Tokyo Metropolitan Institute of Medical Science, Kamikitazawa, Setagaya-ku, Tokyo, Japan
| | - Ryoko Wada
- Tokyo Metropolitan Institute of Medical Science, Kamikitazawa, Setagaya-ku, Tokyo, Japan
| | - Shuei Sugama
- Department of Physiology, Nippon Medical School, Tokyo, Japan
| | - Takato Takenouchi
- Institute of Agrobiological Sciences, National Agriculture and Food Research Organization, Tsukuba, Ibaraki, Japan
| | - Eliezer Masliah
- Division of Neurosciences, National Institute on Aging, National Institutes of Health, Bethesda, MD, USA
| | - Masaaki Waragai
- Tokyo Metropolitan Institute of Medical Science, Kamikitazawa, Setagaya-ku, Tokyo, Japan
| |
Collapse
|
42
|
Kang AR, An HT, Ko J, Choi EJ, Kang S. Ataxin-1 is involved in tumorigenesis of cervical cancer cells via the EGFR-RAS-MAPK signaling pathway. Oncotarget 2017; 8:94606-94618. [PMID: 29212253 PMCID: PMC5706899 DOI: 10.18632/oncotarget.21814] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2017] [Accepted: 09/20/2017] [Indexed: 12/24/2022] Open
Abstract
Ataxin-1 (ATXN1) is a coregulator protein within which expansion of the polyglutamine tract causes spinocerebellar ataxia type 1, an autosomal dominant neurodegenerative disorder. Previously, we reported that ATXN1 regulates the epithelial–mesenchymal transition of cervical cancer cells. In the present study, we demonstrate that ATXN1 is involved in cervical cancer tumorigenesis by promoting the proliferation of human cervical cancer cells. Chromatin immunoprecipitation assays showed that ATXN1 bound to the promoter region within cyclin D1 and activated cyclin D1 transcription, resulting in cell proliferation. ATXN1 promoted cyclin D1 expression through the EGFR–RAS–MAPK signaling pathway. Mouse xenograft tumorigenicity assays showed that ATXN1 downregulation inhibited tumorigenesis in cervical cancer cell lines in nude mice. Human cervical cancer tissue microarrays and immunohistochemical techniques showed that ATXN1 was significantly upregulated in many such tissues. Our results suggest that ATXN1 plays an important role in cervical cancer tumorigenesis and is a prognostic marker for cervical cancer.
Collapse
Affiliation(s)
- A-Ram Kang
- Division of Life Sciences, College of Life Sciences and Biotechnology, Korea University, Seoul 02841, Korea
| | - Hyoung-Tae An
- Division of Life Sciences, College of Life Sciences and Biotechnology, Korea University, Seoul 02841, Korea
| | - Jesang Ko
- Division of Life Sciences, College of Life Sciences and Biotechnology, Korea University, Seoul 02841, Korea
| | - Eui-Ju Choi
- Division of Life Sciences, College of Life Sciences and Biotechnology, Korea University, Seoul 02841, Korea
| | - Seongman Kang
- Division of Life Sciences, College of Life Sciences and Biotechnology, Korea University, Seoul 02841, Korea
| |
Collapse
|
43
|
Huo Z, Luo X, Zhan X, Chu Q, Xu Q, Yao J, Pang H. Genetic analysis of indel markers in three loci associated with Parkinson's disease. PLoS One 2017; 12:e0184269. [PMID: 28873462 PMCID: PMC5584932 DOI: 10.1371/journal.pone.0184269] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2017] [Accepted: 08/21/2017] [Indexed: 11/19/2022] Open
Abstract
The causal mutations and genetic polymorphisms associated with susceptibility to Parkinson’s disease (PD) have been extensively described. To explore the potential contribution of insertion (I)/deletion (D) polymorphisms (indels) to the risk of PD in a Chinese population, we performed genetic analyses of indel loci in ACE, DJ-1, and GIGYF2 genes. Genomic DNA was extracted from venous blood of 348 PD patients and 325 age- and sex-matched controls without neurodegenerative disease. Genotyping of the indel loci was performed by fragment length analysis after PCR and DNA sequencing. Our results showed a statistically significant association for both allele X (alleles without 5) vs. 5 (odds ratio = 1.378, 95% confidence interval = 1.112–1.708, P = 0.003) and genotype 5/X+X/X vs. 5/5 (odds ratio = 1.681, 95% confidence interval = 1.174–2.407, P = 0.004) in the GIGYF2 locus; however, no significant differences were detected for the ACE and DJ-1 indels. After stratification by gender, no significant differences were observed in any indels. These results indicate that the GIGYF2 indel may be associated with increased risk of PD in northern China.
Collapse
Affiliation(s)
- Zhixin Huo
- Department of Forensic Genetics and Biology, China Medical University, Shenyang North New Area, Shenyang, P.R., China
| | - Xiaoguang Luo
- Department of Neurology, 1st Affiliated Hospital of China Medical University, Shenyang, P.R., China
| | - Xiaoni Zhan
- Department of Forensic Genetics and Biology, China Medical University, Shenyang North New Area, Shenyang, P.R., China
| | - Qiaohong Chu
- Department of Forensic Genetics and Biology, China Medical University, Shenyang North New Area, Shenyang, P.R., China
| | - Qin Xu
- Department of Forensic Genetics and Biology, China Medical University, Shenyang North New Area, Shenyang, P.R., China
| | - Jun Yao
- Department of Forensic Genetics and Biology, China Medical University, Shenyang North New Area, Shenyang, P.R., China
| | - Hao Pang
- Department of Forensic Genetics and Biology, China Medical University, Shenyang North New Area, Shenyang, P.R., China
- * E-mail:
| |
Collapse
|
44
|
Sequence configuration of spinocerebellar ataxia type 8 repeat expansions in a Japanese cohort of 797 ataxia subjects. J Neurol Sci 2017; 382:87-90. [PMID: 29111027 DOI: 10.1016/j.jns.2017.08.3256] [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: 01/30/2017] [Revised: 08/04/2017] [Accepted: 08/28/2017] [Indexed: 11/23/2022]
Abstract
Spinocerebellar ataxia type 8 (SCA8), an autosomal dominant neurodegenerative disorder showing slowly progressive cerebellar ataxia, is caused by a tri-nucleotide CTG repeat expansion (CTGexp) in the SCA8 gene. As the CTGexp is not fully penetrant, the significance of screening CTGexp in ataxia subjects remains obscure. We tested SCA8 CTGexp in a cohort of 797 ataxia subjects, and if present, its sequence configuration was analyzed. CTGexp was found in 16 alleles from 14 individuals, 2 of which was homozygous for CTGexp. Nucleotide sequencing disclosed 3 types of CTGexp sequence configurations: uninterrupted CTGexp, tri-nucleotide CTA interruption and CCG interruption. The 2 individuals with homozygous expansions were both sporadic cases with clinical features compatible with SCA8, supporting gene dosage effect. Seven out of 14 CTGexp-positive subjects were also carriers of other SCA expansions [Machado-Joseph disease (n=1), SCA6 (n=3) and SCA31 (n=3)], whereas 7 others were not complicated with such major SCAs. Ages of onset in subjects with pure CTGexp tended to be earlier than those with interrupted CTGexp among the 7 subjects not complicated by major SCAs, suggesting that pure CTGexp have stronger pathogenic effect than interrupted CTGexps. The present study underscores importance of disclosing sequence configuration when testing SCA8.
Collapse
|