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Spencer D, Polke J, Campbell J, Houlden H, Radunovic A. 'Outcomes of genetic testing in the London MND Center: the importance of achieving timely results and correlations to family history'. Amyotroph Lateral Scler Frontotemporal Degener 2024:1-6. [PMID: 38932488 DOI: 10.1080/21678421.2024.2370808] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2024] [Accepted: 06/14/2024] [Indexed: 06/28/2024]
Abstract
Background: Despite recognition of the importance of genetic factors in the pathogenesis of MND and the increasing availability of genetic testing, testing practice remains highly variable. With the arrival of gene-targeted therapies there is a growing need to promptly identify actionable genetic results and patient death before receipt of results raises ethical dilemmas and limits access to novel therapies. Objective: To identify pathogenic mutations within a London tertiary MND center and their correlation with family history. To record waiting times for genetic results and deaths prior to receipt of results. Methods: In this series of 100 cases, genetic testing was offered to all patients with an MND diagnosis from the tertiary clinic. Data on demographics, disease progression and a detailed family history were taken. Time to receipt of genetic results and patient deaths prior to this were recorded. Results: Of the 97 patients who accepted testing a genetic cause was identified in 10%, including seven C9orf72 and two positive SOD1 cases. Only three patients with positive genetic findings had a family history of MND, although alternative neurological diagnoses and symptoms in the family were frequently reported. 14% of patients who underwent testing were deceased by the time results were received, including one actionable SOD1 case. Conclusions: Genetic testing should be made available to all patients who receive an MND diagnosis as family history alone is inadequate to identify potential familial cases. Time to receipt of results remains a significant issue due to the limited life expectancy following diagnosis.
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Affiliation(s)
- Dean Spencer
- Department of Neurology, Barts Health NHS Foundation Trust, London, UK and
| | - James Polke
- Neurogenetics Laboratory, National Hospital for Neurology and Neurosurgery and North Thames Genomics Laboratory Hub, London, UK
| | - Joanna Campbell
- Neurogenetics Laboratory, National Hospital for Neurology and Neurosurgery and North Thames Genomics Laboratory Hub, London, UK
| | - Henry Houlden
- Neurogenetics Laboratory, National Hospital for Neurology and Neurosurgery and North Thames Genomics Laboratory Hub, London, UK
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Roggenbuck J, Eubank BHF, Wright J, Harms MB, Kolb SJ. Evidence-based consensus guidelines for ALS genetic testing and counseling. Ann Clin Transl Neurol 2023; 10:2074-2091. [PMID: 37691292 PMCID: PMC10646996 DOI: 10.1002/acn3.51895] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2023] [Accepted: 08/12/2023] [Indexed: 09/12/2023] Open
Abstract
OBJECTIVE Advances in amyotrophic lateral sclerosis (ALS) gene discovery, ongoing gene therapy trials, and patient demand have driven increased use of ALS genetic testing. Despite this progress, the offer of genetic testing to persons with ALS is not yet "standard of care." Our primary goal is to develop clinical ALS genetic counseling and testing guidelines to improve and standardize genetic counseling and testing practice among neurologists, genetic counselors or any provider caring for persons with ALS. METHODS Core clinical questions were identified and a rapid review performed according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA-P) 2015 method. Guideline recommendations were drafted and the strength of evidence for each recommendation was assessed by combining two systems: the Grading of Recommendations, Assessment, Development and Evaluation (GRADE) System and the Evaluation of Genomic Applications in Practice and Prevention (EGAPP). A modified Delphi approach was used to reach consensus among a group of content experts for each guideline statement. RESULTS A total of 35 guideline statements were developed. In summary, all persons with ALS should be offered single-step genetic testing, consisting of a C9orf72 assay, along with sequencing of SOD1, FUS, and TARDBP, at a minimum. The key education and genetic risk assessments that should be provided before and after testing are delineated. Specific guidance regarding testing methods and reporting for C9orf72 and other genes is provided for commercial laboratories. INTERPRETATION These evidence-based, consensus guidelines will support all stakeholders in the ALS community in navigating benefits and challenges of genetic testing.
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Affiliation(s)
- Jennifer Roggenbuck
- Division of Human Genetics, Department of Internal MedicineThe Ohio State University Wexner Medical CenterColumbusOhioUSA
- Department of NeurologyThe Ohio State University Wexner Medical CenterColumbusOhioUSA
| | - Breda H. F. Eubank
- Health & Physical Education Department, Faculty of Health, Community, & EducationMount Royal University4825 Mount Royal Gate SWCalgaryAlbertaCanada
| | - Joshua Wright
- Department of NeurologyThe Ohio State University Wexner Medical CenterColumbusOhioUSA
| | - Matthew B. Harms
- Department of NeurologyColumbia University Vagelos College of Physicians and SurgeonsNew YorkNew YorkUSA
| | - Stephen J. Kolb
- Department of NeurologyThe Ohio State University Wexner Medical CenterColumbusOhioUSA
- Department of Biological Chemistry & PharmacologyThe Ohio State University Wexner Medical CenterColumbusOhioUSA
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Mahungu AC, Steyn E, Floudiotis N, Wilson LA, Vandrovcova J, Reilly MM, Record CJ, Benatar M, Wu G, Raga S, Wilmshurst JM, Naidu K, Hanna M, Nel M, Heckmann JM. The mutational profile in a South African cohort with inherited neuropathies and spastic paraplegia. Front Neurol 2023; 14:1239725. [PMID: 37712079 PMCID: PMC10497947 DOI: 10.3389/fneur.2023.1239725] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2023] [Accepted: 08/02/2023] [Indexed: 09/16/2023] Open
Abstract
Introduction Limited diagnostics are available for inherited neuromuscular diseases (NMD) in South Africa and (excluding muscle disease) are mainly aimed at the most frequent genes underlying genetic neuropathy (GN) and spastic ataxias in Europeans. In this study, we used next-generation sequencing to screen 61 probands with GN, hereditary spastic paraplegia (HSP), and spastic ataxias for a genetic diagnosis. Methods After identifying four GN probands with PMP22 duplication and one spastic ataxia proband with SCA1, the remaining probands underwent whole exome (n = 26) or genome sequencing (n = 30). The curation of coding/splice region variants using gene panels was guided by allele frequencies from internal African-ancestry control genomes (n = 537) and the Clinical Genome Resource's Sequence Variant Interpretation guidelines. Results Of 32 GN probands, 50% had African-genetic ancestry, and 44% were solved: PMP22 (n = 4); MFN2 (n = 3); one each of MORC2, ATP1A1, ADPRHL2, GJB1, GAN, MPZ, and ATM. Of 29 HSP probands (six with predominant ataxia), 66% had African-genetic ancestry, and 48% were solved: SPG11 (n = 3); KIF1A (n = 2); and one each of SPAST, ATL1, SPG7, PCYT2, PSEN1, ATXN1, ALDH18A1, CYP7B1, and RFT1. Structural variants in SPAST, SPG11, SPG7, MFN2, MPZ, KIF5A, and GJB1 were excluded by computational prediction and manual visualisation. Discussion In this preliminary cohort screening panel of disease genes using WES/WGS data, we solved ~50% of cases, which is similar to diagnostic yields reported for global cohorts. However, the mutational profile among South Africans with GN and HSP differs substantially from that in the Global North.
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Affiliation(s)
- Amokelani C. Mahungu
- Neurology Research Group, Division of Neurology, Department of Medicine, University of Cape Town, Cape Town, South Africa
- Neuroscience Institute, University of Cape Town, Cape Town, South Africa
| | - Elizabeth Steyn
- Neurology Research Group, Division of Neurology, Department of Medicine, University of Cape Town, Cape Town, South Africa
| | - Niki Floudiotis
- Neurology Research Group, Division of Neurology, Department of Medicine, University of Cape Town, Cape Town, South Africa
| | - Lindsay A. Wilson
- Department of Neuromuscular Diseases, Queen Square Institute of Neurology, University College London, London, United Kingdom
| | - Jana Vandrovcova
- Department of Neuromuscular Diseases, Queen Square Institute of Neurology, University College London, London, United Kingdom
| | - Mary M. Reilly
- Department of Neuromuscular Disease, Queen Square UCL Institute of Neurology and the National Hospital of Neurology and Neurosurgery, London, United Kingdom
| | - Christopher J. Record
- Department of Neuromuscular Disease, Queen Square UCL Institute of Neurology and the National Hospital of Neurology and Neurosurgery, London, United Kingdom
| | - Michael Benatar
- Department of Neurology, University of Miami Miller School of Medicine, Miami, FL, United States
| | - Gang Wu
- Center for Applied Bioinformatics, St. Jude Children's Research Hospital, Memphis, TN, United States
| | - Sharika Raga
- Neuroscience Institute, University of Cape Town, Cape Town, South Africa
- Division of Paediatric Neurology, Department of Paediatrics and Child Health, Red Cross War Memorial Children's Hospital, University of Cape Town, Cape Town, South Africa
| | - Jo M. Wilmshurst
- Neuroscience Institute, University of Cape Town, Cape Town, South Africa
- Division of Paediatric Neurology, Department of Paediatrics and Child Health, Red Cross War Memorial Children's Hospital, University of Cape Town, Cape Town, South Africa
| | - Kireshnee Naidu
- Neurology Research Group, Division of Neurology, Department of Medicine, University of Cape Town, Cape Town, South Africa
| | - Michael Hanna
- Department of Neuromuscular Diseases, Queen Square Institute of Neurology, University College London, London, United Kingdom
- NHS Highly Specialised Service for Rare Mitochondrial Disorders, Queen Square Centre for Neuromuscular Diseases, The National Hospital for Neurology and Neurosurgery, London, United Kingdom
| | - Melissa Nel
- Neurology Research Group, Division of Neurology, Department of Medicine, University of Cape Town, Cape Town, South Africa
- Neuroscience Institute, University of Cape Town, Cape Town, South Africa
| | - Jeannine M. Heckmann
- Neurology Research Group, Division of Neurology, Department of Medicine, University of Cape Town, Cape Town, South Africa
- Neuroscience Institute, University of Cape Town, Cape Town, South Africa
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Monnakgotla NR, Mahungu AC, Heckmann JM, Botha G, Mulder NJ, Wu G, Rampersaud E, Myers J, Van Blitterswijk M, Rademakers R, Taylor JP, Wuu J, Benatar M, Nel M. Analysis of Structural Variants Previously Associated With ALS in Europeans Highlights Genomic Architectural Differences in Africans. Neurol Genet 2023; 9:e200077. [PMID: 37346932 PMCID: PMC10281237 DOI: 10.1212/nxg.0000000000200077] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2023] [Accepted: 04/03/2023] [Indexed: 06/23/2023]
Abstract
Background and Objectives Amyotrophic lateral sclerosis (ALS) is a degenerative condition of the brain and spinal cord in which protein-coding variants in known ALS disease genes explain a minority of sporadic cases. There is a growing interest in the role of noncoding structural variants (SVs) as ALS risk variants or genetic modifiers of ALS phenotype. In small European samples, specific short SV alleles in noncoding regulatory regions of SCAF4, SQSTM1, and STMN2 have been reported to be associated with ALS, and several groups have investigated the possible role of SMN1/SMN2 gene copy numbers in ALS susceptibility and clinical severity. Methods Using short-read whole genome sequencing (WGS) data, we investigated putative ALS-susceptibility SCAF4 (3'UTR poly-T repeat), SQSTM1 (intron 5 AAAC insertion), and STMN2 (intron 3 CA repeat) alleles in African ancestry patients with ALS and described the architecture of the SMN1/SMN2 gene region. South African cases with ALS (n = 114) were compared with ancestry-matched controls (n = 150), 1000 Genomes Project samples (n = 2,336), and H3Africa Genotyping Chip Project samples (n = 347). Results There was no association with previously reported SCAF4 poly-T repeat, SQSTM1 AAAC insertion, and long STMN2 CA alleles with ALS risk in South Africans (p > 0.2). Similarly, SMN1 and SMN2 gene copy numbers did not differ between South Africans with ALS and matched population controls (p > 0.9). Notably, 20% of the African samples in this study had no SMN2 gene copies, which is a higher frequency than that reported in Europeans (approximately 7%). Discussion We did not replicate the reported association of SCAF4, SQSTM1, and STMN2 short SVs with ALS in a small South African sample. In addition, we found no link between SMN1 and SMN2 copy numbers and susceptibility to ALS in this South African sample, which is similar to the conclusion of a recent meta-analysis of European studies. However, the SMN gene region findings in Africans replicate previous results from East and West Africa and highlight the importance of including diverse population groups in disease gene discovery efforts. The clinically relevant differences in the SMN gene architecture between African and non-African populations may affect the effectiveness of targeted SMN2 gene therapy for related diseases such as spinal muscular atrophy.
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Affiliation(s)
- Nomakhosazana R Monnakgotla
- From the Neurology Research Group (N.R.M., A.C.M., J.M.H., M.N.), Division of Neurology, Department of Medicine; Neuroscience Institute (N.R.M., A.C.M., J.M.H., M.N.); Computational Biology Division (G.B., N.J.M.), Institute of Infectious Disease and Molecular Medicine, University of Cape Town, South Africa; Center for Applied Bioinformatics (G.W., E.R., J.M.), St. Jude Children's Research Hospital, Memphis, TN; Department of Neuroscience (M.V.B.), Mayo Clinic, Jacksonville, FL; Center for Molecular Neurology (R.R.), University of Antwerp, Belgium; Department of Cell and Molecular Biology (J.P.T.), St. Jude Children's Research Hospital, Memphis, TN; and Department of Neurology (J.W., M.B.), University of Miami, FL
| | - Amokelani C Mahungu
- From the Neurology Research Group (N.R.M., A.C.M., J.M.H., M.N.), Division of Neurology, Department of Medicine; Neuroscience Institute (N.R.M., A.C.M., J.M.H., M.N.); Computational Biology Division (G.B., N.J.M.), Institute of Infectious Disease and Molecular Medicine, University of Cape Town, South Africa; Center for Applied Bioinformatics (G.W., E.R., J.M.), St. Jude Children's Research Hospital, Memphis, TN; Department of Neuroscience (M.V.B.), Mayo Clinic, Jacksonville, FL; Center for Molecular Neurology (R.R.), University of Antwerp, Belgium; Department of Cell and Molecular Biology (J.P.T.), St. Jude Children's Research Hospital, Memphis, TN; and Department of Neurology (J.W., M.B.), University of Miami, FL
| | - Jeannine M Heckmann
- From the Neurology Research Group (N.R.M., A.C.M., J.M.H., M.N.), Division of Neurology, Department of Medicine; Neuroscience Institute (N.R.M., A.C.M., J.M.H., M.N.); Computational Biology Division (G.B., N.J.M.), Institute of Infectious Disease and Molecular Medicine, University of Cape Town, South Africa; Center for Applied Bioinformatics (G.W., E.R., J.M.), St. Jude Children's Research Hospital, Memphis, TN; Department of Neuroscience (M.V.B.), Mayo Clinic, Jacksonville, FL; Center for Molecular Neurology (R.R.), University of Antwerp, Belgium; Department of Cell and Molecular Biology (J.P.T.), St. Jude Children's Research Hospital, Memphis, TN; and Department of Neurology (J.W., M.B.), University of Miami, FL
| | - Gerrit Botha
- From the Neurology Research Group (N.R.M., A.C.M., J.M.H., M.N.), Division of Neurology, Department of Medicine; Neuroscience Institute (N.R.M., A.C.M., J.M.H., M.N.); Computational Biology Division (G.B., N.J.M.), Institute of Infectious Disease and Molecular Medicine, University of Cape Town, South Africa; Center for Applied Bioinformatics (G.W., E.R., J.M.), St. Jude Children's Research Hospital, Memphis, TN; Department of Neuroscience (M.V.B.), Mayo Clinic, Jacksonville, FL; Center for Molecular Neurology (R.R.), University of Antwerp, Belgium; Department of Cell and Molecular Biology (J.P.T.), St. Jude Children's Research Hospital, Memphis, TN; and Department of Neurology (J.W., M.B.), University of Miami, FL
| | - Nicola J Mulder
- From the Neurology Research Group (N.R.M., A.C.M., J.M.H., M.N.), Division of Neurology, Department of Medicine; Neuroscience Institute (N.R.M., A.C.M., J.M.H., M.N.); Computational Biology Division (G.B., N.J.M.), Institute of Infectious Disease and Molecular Medicine, University of Cape Town, South Africa; Center for Applied Bioinformatics (G.W., E.R., J.M.), St. Jude Children's Research Hospital, Memphis, TN; Department of Neuroscience (M.V.B.), Mayo Clinic, Jacksonville, FL; Center for Molecular Neurology (R.R.), University of Antwerp, Belgium; Department of Cell and Molecular Biology (J.P.T.), St. Jude Children's Research Hospital, Memphis, TN; and Department of Neurology (J.W., M.B.), University of Miami, FL
| | - Gang Wu
- From the Neurology Research Group (N.R.M., A.C.M., J.M.H., M.N.), Division of Neurology, Department of Medicine; Neuroscience Institute (N.R.M., A.C.M., J.M.H., M.N.); Computational Biology Division (G.B., N.J.M.), Institute of Infectious Disease and Molecular Medicine, University of Cape Town, South Africa; Center for Applied Bioinformatics (G.W., E.R., J.M.), St. Jude Children's Research Hospital, Memphis, TN; Department of Neuroscience (M.V.B.), Mayo Clinic, Jacksonville, FL; Center for Molecular Neurology (R.R.), University of Antwerp, Belgium; Department of Cell and Molecular Biology (J.P.T.), St. Jude Children's Research Hospital, Memphis, TN; and Department of Neurology (J.W., M.B.), University of Miami, FL
| | - Evadnie Rampersaud
- From the Neurology Research Group (N.R.M., A.C.M., J.M.H., M.N.), Division of Neurology, Department of Medicine; Neuroscience Institute (N.R.M., A.C.M., J.M.H., M.N.); Computational Biology Division (G.B., N.J.M.), Institute of Infectious Disease and Molecular Medicine, University of Cape Town, South Africa; Center for Applied Bioinformatics (G.W., E.R., J.M.), St. Jude Children's Research Hospital, Memphis, TN; Department of Neuroscience (M.V.B.), Mayo Clinic, Jacksonville, FL; Center for Molecular Neurology (R.R.), University of Antwerp, Belgium; Department of Cell and Molecular Biology (J.P.T.), St. Jude Children's Research Hospital, Memphis, TN; and Department of Neurology (J.W., M.B.), University of Miami, FL
| | - Jason Myers
- From the Neurology Research Group (N.R.M., A.C.M., J.M.H., M.N.), Division of Neurology, Department of Medicine; Neuroscience Institute (N.R.M., A.C.M., J.M.H., M.N.); Computational Biology Division (G.B., N.J.M.), Institute of Infectious Disease and Molecular Medicine, University of Cape Town, South Africa; Center for Applied Bioinformatics (G.W., E.R., J.M.), St. Jude Children's Research Hospital, Memphis, TN; Department of Neuroscience (M.V.B.), Mayo Clinic, Jacksonville, FL; Center for Molecular Neurology (R.R.), University of Antwerp, Belgium; Department of Cell and Molecular Biology (J.P.T.), St. Jude Children's Research Hospital, Memphis, TN; and Department of Neurology (J.W., M.B.), University of Miami, FL
| | - Marka Van Blitterswijk
- From the Neurology Research Group (N.R.M., A.C.M., J.M.H., M.N.), Division of Neurology, Department of Medicine; Neuroscience Institute (N.R.M., A.C.M., J.M.H., M.N.); Computational Biology Division (G.B., N.J.M.), Institute of Infectious Disease and Molecular Medicine, University of Cape Town, South Africa; Center for Applied Bioinformatics (G.W., E.R., J.M.), St. Jude Children's Research Hospital, Memphis, TN; Department of Neuroscience (M.V.B.), Mayo Clinic, Jacksonville, FL; Center for Molecular Neurology (R.R.), University of Antwerp, Belgium; Department of Cell and Molecular Biology (J.P.T.), St. Jude Children's Research Hospital, Memphis, TN; and Department of Neurology (J.W., M.B.), University of Miami, FL
| | - Rosa Rademakers
- From the Neurology Research Group (N.R.M., A.C.M., J.M.H., M.N.), Division of Neurology, Department of Medicine; Neuroscience Institute (N.R.M., A.C.M., J.M.H., M.N.); Computational Biology Division (G.B., N.J.M.), Institute of Infectious Disease and Molecular Medicine, University of Cape Town, South Africa; Center for Applied Bioinformatics (G.W., E.R., J.M.), St. Jude Children's Research Hospital, Memphis, TN; Department of Neuroscience (M.V.B.), Mayo Clinic, Jacksonville, FL; Center for Molecular Neurology (R.R.), University of Antwerp, Belgium; Department of Cell and Molecular Biology (J.P.T.), St. Jude Children's Research Hospital, Memphis, TN; and Department of Neurology (J.W., M.B.), University of Miami, FL
| | - J Paul Taylor
- From the Neurology Research Group (N.R.M., A.C.M., J.M.H., M.N.), Division of Neurology, Department of Medicine; Neuroscience Institute (N.R.M., A.C.M., J.M.H., M.N.); Computational Biology Division (G.B., N.J.M.), Institute of Infectious Disease and Molecular Medicine, University of Cape Town, South Africa; Center for Applied Bioinformatics (G.W., E.R., J.M.), St. Jude Children's Research Hospital, Memphis, TN; Department of Neuroscience (M.V.B.), Mayo Clinic, Jacksonville, FL; Center for Molecular Neurology (R.R.), University of Antwerp, Belgium; Department of Cell and Molecular Biology (J.P.T.), St. Jude Children's Research Hospital, Memphis, TN; and Department of Neurology (J.W., M.B.), University of Miami, FL
| | - Joanne Wuu
- From the Neurology Research Group (N.R.M., A.C.M., J.M.H., M.N.), Division of Neurology, Department of Medicine; Neuroscience Institute (N.R.M., A.C.M., J.M.H., M.N.); Computational Biology Division (G.B., N.J.M.), Institute of Infectious Disease and Molecular Medicine, University of Cape Town, South Africa; Center for Applied Bioinformatics (G.W., E.R., J.M.), St. Jude Children's Research Hospital, Memphis, TN; Department of Neuroscience (M.V.B.), Mayo Clinic, Jacksonville, FL; Center for Molecular Neurology (R.R.), University of Antwerp, Belgium; Department of Cell and Molecular Biology (J.P.T.), St. Jude Children's Research Hospital, Memphis, TN; and Department of Neurology (J.W., M.B.), University of Miami, FL
| | - Michael Benatar
- From the Neurology Research Group (N.R.M., A.C.M., J.M.H., M.N.), Division of Neurology, Department of Medicine; Neuroscience Institute (N.R.M., A.C.M., J.M.H., M.N.); Computational Biology Division (G.B., N.J.M.), Institute of Infectious Disease and Molecular Medicine, University of Cape Town, South Africa; Center for Applied Bioinformatics (G.W., E.R., J.M.), St. Jude Children's Research Hospital, Memphis, TN; Department of Neuroscience (M.V.B.), Mayo Clinic, Jacksonville, FL; Center for Molecular Neurology (R.R.), University of Antwerp, Belgium; Department of Cell and Molecular Biology (J.P.T.), St. Jude Children's Research Hospital, Memphis, TN; and Department of Neurology (J.W., M.B.), University of Miami, FL
| | - Melissa Nel
- From the Neurology Research Group (N.R.M., A.C.M., J.M.H., M.N.), Division of Neurology, Department of Medicine; Neuroscience Institute (N.R.M., A.C.M., J.M.H., M.N.); Computational Biology Division (G.B., N.J.M.), Institute of Infectious Disease and Molecular Medicine, University of Cape Town, South Africa; Center for Applied Bioinformatics (G.W., E.R., J.M.), St. Jude Children's Research Hospital, Memphis, TN; Department of Neuroscience (M.V.B.), Mayo Clinic, Jacksonville, FL; Center for Molecular Neurology (R.R.), University of Antwerp, Belgium; Department of Cell and Molecular Biology (J.P.T.), St. Jude Children's Research Hospital, Memphis, TN; and Department of Neurology (J.W., M.B.), University of Miami, FL
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Floudiotis N, Modi G, Mochan A. Motor neuron disease in black African patients at a tertiary care hospital in Soweto, South Africa. J Neurol Sci 2023; 451:120710. [PMID: 37379726 DOI: 10.1016/j.jns.2023.120710] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2023] [Revised: 06/07/2023] [Accepted: 06/08/2023] [Indexed: 06/30/2023]
Abstract
INTRODUCTION In this brief report, we describe the nature of ALS in a South African cohort of patients of Black African ancestry - a population which has been historically understudied. METHODS We performed a chart review of all patients attending the ALS/MND clinic at the Chris Hani Baragwanath Academic Hospital in Soweto, Johannesburg, South Africa, during the period 1 January 2015 to 30 June 2020. Cross-sectional demographic and clinical data captured at the time of diagnosis was collected. RESULTS Seventy-one patients were included in the study. Males constituted 66% (n = 47), with a male to female sex ratio of 2:1. The median age at onset of symptoms was 46 years (IQR 40-57) with a median disease duration at diagnosis (diagnostic delay) of 2 years (IQR 1-3). The onset was spinal in 76% and bulbar in 23%. The median ALSFRS-R score at time of presentation was 29 (IQR 23-38.5). The median ALSFRS-R slope (unit/month) was 0.80 (IQR 0.43-1.39). Sixty five patients (92%) were diagnosed with the classic ALS phenotype. Fourteen patients were known to be HIV positive, and of those, 12 were on antiretroviral treatment (ART). None of the patients had familial ALS. CONCLUSION Our findings of an earlier age at symptom onset and seemingly advanced disease at presentation in patients with Black African ancestry support the existing literature on the African population.
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Affiliation(s)
- Niki Floudiotis
- Division of Neurology, Department of Neurosciences, School of Clinical Medicine, Faculty of Health Sciences, University of the Witwatersrand, 7 York Road Parktown, 2193 Johannesburg, South Africa
| | - Girish Modi
- Division of Neurology, Department of Neurosciences, School of Clinical Medicine, Faculty of Health Sciences, University of the Witwatersrand, 7 York Road Parktown, 2193 Johannesburg, South Africa
| | - Andre Mochan
- Division of Neurology, Department of Neurosciences, School of Clinical Medicine, Faculty of Health Sciences, University of the Witwatersrand, 7 York Road Parktown, 2193 Johannesburg, South Africa.
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del Campo M, Zetterberg H, Gandy S, Onyike CU, Oliveira F, Udeh‐Momoh C, Lleó A, Teunissen CE, Pijnenburg Y. New developments of biofluid-based biomarkers for routine diagnosis and disease trajectories in frontotemporal dementia. Alzheimers Dement 2022; 18:2292-2307. [PMID: 35235699 PMCID: PMC9790674 DOI: 10.1002/alz.12643] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2021] [Revised: 02/04/2022] [Accepted: 02/04/2022] [Indexed: 01/31/2023]
Abstract
Frontotemporal dementia (FTD) covers a spectrum of neurodegenerative disorders with different phenotypes, genetic backgrounds, and pathological states. Its clinicopathological diversity challenges the diagnostic process and the execution of clinical trials, calling for specific diagnostic biomarkers of pathologic FTD types. There is also a need for biomarkers that facilitate disease staging, quantification of severity, monitoring in clinics and observational studies, and for evaluation of target engagement and treatment response in clinical trials. This review discusses current FTD biofluid-based biomarker knowledge taking into account the differing applications. The limitations, knowledge gaps, and challenges for the development and implementation of such markers are also examined. Strategies to overcome these hurdles are proposed, including the technologies available, patient cohorts, and collaborative research initiatives. Access to robust and reliable biomarkers that define the exact underlying pathophysiological FTD process will meet the needs for specific diagnosis, disease quantitation, clinical monitoring, and treatment development.
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Affiliation(s)
- Marta del Campo
- Departamento de Ciencias Farmacéuticas y de la SaludFacultad de FarmaciaUniversidad San Pablo‐CEUCEU UniversitiesMadridSpain
| | - Henrik Zetterberg
- Institute of Neuroscience and PhysiologyThe Sahlgrenska Academy at the University of GothenburgGothenburgSweden,Clinical Neurochemistry LaboratorySahlgrenska University HospitalMölndalSweden,UK Dementia Research Institute at UCLLondonUK,Department of Neurodegenerative DiseaseUCL Institute of NeurologyLondonUK,Hong Kong Center for Neurodegenerative DiseasesHong KongChina
| | - Sam Gandy
- Department of NeurologyIcahn School of Medicine at Mount SinaiNew YorkNew YorkUSA
| | - Chiadi U Onyike
- Division of Geriatric Psychiatry and NeuropsychiatryThe Johns Hopkins University School of MedicineBaltimoreMarylandUSA
| | - Fabricio Oliveira
- Department of Neurology and NeurosurgeryEscola Paulista de MedicinaFederal University of São Paulo (UNIFESP)São PauloSão PauloBrazil
| | - Chi Udeh‐Momoh
- Ageing Epidemiology Research UnitSchool of Public HealthFaculty of MedicineImperial College LondonLondonUK,Translational Health SciencesFaculty of MedicineUniversity of BristolBristolUK
| | - Alberto Lleó
- Neurology DepartmentHospital de la Santa Creu I Sant PauBarcelonaSpain
| | - Charlotte E. Teunissen
- Neurochemistry LaboratoryDepartment of Clinical ChemistryAmsterdam NeuroscienceAmsterdam University Medical CentersVrije UniversiteitAmsterdamthe Netherlands
| | - Yolande Pijnenburg
- Alzheimer Center AmsterdamDepartment of NeurologyAmsterdam NeuroscienceVrije Universiteit AmsterdamAmsterdam UMCAmsterdamthe Netherlands
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Breevoort S, Gibson S, Figueroa K, Bromberg M, Pulst S. Expanding Clinical Spectrum of C9ORF72-Related Disorders and Promising Therapeutic Strategies: A Review. Neurol Genet 2022; 8:e670. [PMID: 35620137 PMCID: PMC9128039 DOI: 10.1212/nxg.0000000000000670] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2022] [Accepted: 03/18/2022] [Indexed: 11/15/2022]
Abstract
In 2011, a pathogenic hexanucleotide repeat expansion in the C9ORF72 gene was discovered to be the leading genetic cause of amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD). Before this, the C9ORF72 gene and its protein were unknown. The repeat expansion was found to cause both haploinsufficiency and gain of toxicity through aggregating RNA products and dipeptide repeat proteins. A worldwide effort was then initiated to define C9ORF72 ALS/FTD and unravel the pathogenic mechanism for the development of therapeutic options. A decade later, C9ORF72 genetic testing is readily available. There is now an increasing appreciation that C9ORF72 not only is the leading genetic cause of ALS/FTD but may contribute to a spectrum of disorders. This article reviews what is currently known about the C9ORF72 expansion and how C9ORF72 expansion manifests in ALS, FTD, psychiatric disorders, and movement disorders. With therapeutic strategies fast approaching the clinic, earlier recognition of possible C9ORF72 expansion related disorders is even more paramount to improve patient care.
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Affiliation(s)
| | - Summer Gibson
- Department of Neurology, University of Utah, Salt Lake City
| | - Karla Figueroa
- Department of Neurology, University of Utah, Salt Lake City
| | - Mark Bromberg
- Department of Neurology, University of Utah, Salt Lake City
| | - Stefan Pulst
- Department of Neurology, University of Utah, Salt Lake City
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Hou X, Li W, Liu P, Liu Z, Yuan Y, Ni J, Shen L, Tang B, Wang J. The Clinical and Ploynucleotide Repeat Expansion Analysis of ATXN2, NOP56, AR and C9orf72 in Patients With ALS From Mainland China. Front Neurol 2022; 13:811202. [PMID: 35599735 PMCID: PMC9120572 DOI: 10.3389/fneur.2022.811202] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2021] [Accepted: 04/04/2022] [Indexed: 11/13/2022] Open
Abstract
Background Repeat expansions, including those in C9orf72 and ATXN2, have been implicated in amyotrophic lateral sclerosis (ALS). However, there have been few studies on the association of AR and NOP56 repeat expansion with ALS, especially in China. Accordingly, we aimed to evaluate the frequency of C9orf72 and ATXN2 repeat mutations and investigate whether NOP56 and AR repeat expansion are risk factors for ALS. Methods In this study, 736 ALS patients and several hundred healthy controls were recruited. Polymerase chain reaction (PCR) and repeat-primed PCR (RP-PCR) were performed to determine the repeat lengths in C9orf72, ATXN2, AR, and NOP56. Results GGGGCC repeats in C9orf72 were observed in six ALS patients (0.8%, 6/736) but not in any of the controls (0/365). The patients with pathogenic GGGGCC repeats showed shorter median survival times than those with a normal genotype (p = 0.006). Regarding ATXN2 CAG repeats, we identified that intermediate repeat lengths (29–34 copies) were associated with ALS (p = 0.033), and there was no difference in clinical characteristics between the groups with and without intermediate repeats (p > 0.05). Meanwhile, we observed that there was no association between the repeat size in AR and NOP56 and ALS (p > 0.05). Conclusions Our results demonstrated that pathogenetic repeats in C9orf72 are rare in China, while intermediate CAG repeats in ATXN2 are more frequent but have no effect on disease phenotypes; the repeat size in AR and NOP56 may not be a risk factor for ALS.
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Affiliation(s)
- Xiaorong Hou
- Department of Neurology, Xiangya Hospital, Central South University, Changsha, China
| | - Wanzhen Li
- Department of Neurology, Xiangya Hospital, Central South University, Changsha, China
| | - Pan Liu
- Department of Neurology, Xiangya Hospital, Central South University, Changsha, China
| | - Zhen Liu
- Department of Neurology, Xiangya Hospital, Central South University, Changsha, China
| | - Yanchun Yuan
- Department of Neurology, Xiangya Hospital, Central South University, Changsha, China
| | - Jie Ni
- Department of Neurology, Xiangya Hospital, Central South University, Changsha, China
| | - Lu Shen
- Department of Neurology, Xiangya Hospital, Central South University, Changsha, China
- National Clinical Research Center for Geriatric Diseases, Xiangya Hospital, Central South University, Changsha, China
- Key Laboratory of Hunan Province in Neurodegenerative Disorders, Central South University, Changsha, China
- Laboratory of Medical Genetics, Central South University, Changsha, China
- Engineering Research Center of Hunan Province in Cognitive Impairment Disorders, Central South University, Changsha, China
- Hunan International Scientific and Technological Cooperation Base of Neurodegenerative and Neurogenetic Diseases, Changsha, China
| | - Beisha Tang
- Department of Neurology, Xiangya Hospital, Central South University, Changsha, China
- National Clinical Research Center for Geriatric Diseases, Xiangya Hospital, Central South University, Changsha, China
- Key Laboratory of Hunan Province in Neurodegenerative Disorders, Central South University, Changsha, China
- Laboratory of Medical Genetics, Central South University, Changsha, China
- Engineering Research Center of Hunan Province in Cognitive Impairment Disorders, Central South University, Changsha, China
- Hunan International Scientific and Technological Cooperation Base of Neurodegenerative and Neurogenetic Diseases, Changsha, China
| | - Junling Wang
- Department of Neurology, Xiangya Hospital, Central South University, Changsha, China
- National Clinical Research Center for Geriatric Diseases, Xiangya Hospital, Central South University, Changsha, China
- Key Laboratory of Hunan Province in Neurodegenerative Disorders, Central South University, Changsha, China
- Laboratory of Medical Genetics, Central South University, Changsha, China
- Engineering Research Center of Hunan Province in Cognitive Impairment Disorders, Central South University, Changsha, China
- Hunan International Scientific and Technological Cooperation Base of Neurodegenerative and Neurogenetic Diseases, Changsha, China
- *Correspondence: Junling Wang
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Albertyn CH, Hardy A, Bakker LA, Hlangani M, Van Der Walt K, Zeilinga B, Thomas KGF, Heckmann JM. Adaptation and norming of the Edinburgh Cognitive and behavioural amyotrophic lateral sclerosis screen (ECAS) for three language groups in South Africa. Amyotroph Lateral Scler Frontotemporal Degener 2022; 23:532-541. [PMID: 35118918 DOI: 10.1080/21678421.2022.2030361] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022]
Abstract
Objectives: To adapt and translate the Edinburgh Cognitive and behavioural amyotrophic lateral sclerosis screen (ECAS); to generate preliminary normative data for three language groups in South Africa (SA); to assess the convergent validity of the ECAS in SA samples. Methods: The ECAS was linguistically and culturally adapted for Afrikaans-, isiXhosa-, and English-speaking SA adults (n = 108, 100, and 53, respectively). Each language group was stratified by age and educational level. Cutoff scores for cognitive impairment were set at the group mean minus two standard deviations (SDs). A pilot sample of ALS patients and controls (n = 21 each) were administered the ECAS and an extensive neuropsychological evaluation (NPE) and the Montreal Cognitive Assessment (MoCA) to assess convergent validity. Results: Across the three language groups, the total ECAS cutoff scores ranged from 68 to 97. The ECAS score correlated significantly positively with educational level (p < 0.001) and negatively with age (p < 0.005). The restricted letter fluency task demonstrated a floor effect, particularly in Afrikaans-speakers. The mean total ECAS score (±SD) was similar in ALS patients (103.52 ± 11.90) and controls (100.67 ± 20.49; p = 0.58). Three (14.3%) ALS patients scored below the cutoff for cognitive impairment. Correlations between individual ECAS subtests and analogous NPE tests ranged from weak to moderate. The MoCA score was significantly positively correlated with the ECAS total score (r = 0.59; p = < 0.001). Conclusions: The adapted ECAS and associated normative data will aid cognitive screening of African ALS patients. Larger participant numbers are needed to assess the validity of the adapted instrument.
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Affiliation(s)
- Christine H Albertyn
- Neurology Research Group, UCT Neuroscience Institute, University of Cape Town (UCT), Cape Town, South Africa
| | - Anneli Hardy
- Department of Statistical Sciences, Statistical Consulting Service, University of Cape Town, Cape Town, South Africa
| | - Leonhard A Bakker
- Department of Neurology, Brain Centre Rudolf Magnus, University Medical Centre Utrecht, Utrecht, The Netherlands
| | - Makhaya Hlangani
- Neurology Research Group, UCT Neuroscience Institute, University of Cape Town (UCT), Cape Town, South Africa
| | - Kristien Van Der Walt
- Neurology Research Group, UCT Neuroscience Institute, University of Cape Town (UCT), Cape Town, South Africa
| | - Braam Zeilinga
- Neurology Research Group, UCT Neuroscience Institute, University of Cape Town (UCT), Cape Town, South Africa.,Department of Psychology, and UCT Neuroscience Institute, University of Cape Town, Cape Town, South Africa
| | - Kevin G F Thomas
- Department of Psychology, and UCT Neuroscience Institute, University of Cape Town, Cape Town, South Africa
| | - Jeannine M Heckmann
- Neurology Research Group, UCT Neuroscience Institute, University of Cape Town (UCT), Cape Town, South Africa
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10
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Nel M, Mahungu AC, Monnakgotla N, Botha GR, Mulder NJ, Wu G, Rampersaud E, van Blitterswijk M, Wuu J, Cooley A, Myers J, Rademakers R, Taylor JP, Benatar M, Heckmann JM. Revealing the Mutational Spectrum in Southern Africans With Amyotrophic Lateral Sclerosis. Neurol Genet 2022; 8:e654. [PMID: 35047667 PMCID: PMC8756565 DOI: 10.1212/nxg.0000000000000654] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2021] [Accepted: 12/08/2021] [Indexed: 11/15/2022]
Abstract
Background and Objectives To perform the first screen of 44 amyotrophic lateral sclerosis (ALS) genes in a cohort of African genetic ancestry individuals with ALS using whole-genome sequencing (WGS) data. Methods One hundred three consecutive cases with probable/definite ALS (using the revised El Escorial criteria), and self-categorized as African genetic ancestry, underwent WGS using various Illumina platforms. As population controls, 238 samples from various African WGS data sets were included. Our analysis was restricted to 44 ALS genes, which were curated for rare sequence variants and classified according to the American College of Medical Genetics guidelines as likely benign, uncertain significance, likely pathogenic, or pathogenic variants. Results Thirteen percent of 103 ALS cases harbored pathogenic variants; 5 different SOD1 variants (N87S, G94D, I114T, L145S, and L145F) in 5 individuals (5%, 1 familial case), pathogenic C9orf72 repeat expansions in 7 individuals (7%, 1 familial case) and a likely pathogenic ANXA11 (G38R) variant in 1 individual. Thirty individuals (29%) harbored ≥1 variant of uncertain significance; 10 of these variants had limited pathogenic evidence, although this was insufficient to permit confident classification as pathogenic. Discussion Our findings show that known ALS genes can be expected to identify a genetic cause of disease in >11% of sporadic ALS cases of African genetic ancestry. Similar to European cohorts, the 2 most frequent genes harboring pathogenic variants in this population group are C9orf72 and SOD1.
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Affiliation(s)
- Melissa Nel
- Neurology Research Group (M.N., A.C.M., N.M., J.M.H.), Neuroscience Institute, University of Cape Town; Computational Biology Division (M.N., A.C.M., N.M., G.R.B., N.J.M.), Institute of Infectious Disease and Molecular Medicine, Cape Town, South Africa; Center for Applied Bioinformatics (G.W., E.R., J.M.), St. Jude Children's Research Hospital, Memphis, TN; Department of Neuroscience (M.v.B.), Mayo Clinic, Jacksonville, FL; Department of Neurology (J.W., A.C., M.B.), University of Miami, FL; Center for Molecular Neurology (R.R.), University of Antwerp, Belguim; Department of Cell and Molecular Biology (J.P.T.), St. Jude Children's Research Hospital, Memphis, TN; and Neurology (J.M.H.), Department of Medicine, University of Cape Town, South Africa
| | - Amokelani C Mahungu
- Neurology Research Group (M.N., A.C.M., N.M., J.M.H.), Neuroscience Institute, University of Cape Town; Computational Biology Division (M.N., A.C.M., N.M., G.R.B., N.J.M.), Institute of Infectious Disease and Molecular Medicine, Cape Town, South Africa; Center for Applied Bioinformatics (G.W., E.R., J.M.), St. Jude Children's Research Hospital, Memphis, TN; Department of Neuroscience (M.v.B.), Mayo Clinic, Jacksonville, FL; Department of Neurology (J.W., A.C., M.B.), University of Miami, FL; Center for Molecular Neurology (R.R.), University of Antwerp, Belguim; Department of Cell and Molecular Biology (J.P.T.), St. Jude Children's Research Hospital, Memphis, TN; and Neurology (J.M.H.), Department of Medicine, University of Cape Town, South Africa
| | - Nomakhosazana Monnakgotla
- Neurology Research Group (M.N., A.C.M., N.M., J.M.H.), Neuroscience Institute, University of Cape Town; Computational Biology Division (M.N., A.C.M., N.M., G.R.B., N.J.M.), Institute of Infectious Disease and Molecular Medicine, Cape Town, South Africa; Center for Applied Bioinformatics (G.W., E.R., J.M.), St. Jude Children's Research Hospital, Memphis, TN; Department of Neuroscience (M.v.B.), Mayo Clinic, Jacksonville, FL; Department of Neurology (J.W., A.C., M.B.), University of Miami, FL; Center for Molecular Neurology (R.R.), University of Antwerp, Belguim; Department of Cell and Molecular Biology (J.P.T.), St. Jude Children's Research Hospital, Memphis, TN; and Neurology (J.M.H.), Department of Medicine, University of Cape Town, South Africa
| | - Gerrit R Botha
- Neurology Research Group (M.N., A.C.M., N.M., J.M.H.), Neuroscience Institute, University of Cape Town; Computational Biology Division (M.N., A.C.M., N.M., G.R.B., N.J.M.), Institute of Infectious Disease and Molecular Medicine, Cape Town, South Africa; Center for Applied Bioinformatics (G.W., E.R., J.M.), St. Jude Children's Research Hospital, Memphis, TN; Department of Neuroscience (M.v.B.), Mayo Clinic, Jacksonville, FL; Department of Neurology (J.W., A.C., M.B.), University of Miami, FL; Center for Molecular Neurology (R.R.), University of Antwerp, Belguim; Department of Cell and Molecular Biology (J.P.T.), St. Jude Children's Research Hospital, Memphis, TN; and Neurology (J.M.H.), Department of Medicine, University of Cape Town, South Africa
| | - Nicola J Mulder
- Neurology Research Group (M.N., A.C.M., N.M., J.M.H.), Neuroscience Institute, University of Cape Town; Computational Biology Division (M.N., A.C.M., N.M., G.R.B., N.J.M.), Institute of Infectious Disease and Molecular Medicine, Cape Town, South Africa; Center for Applied Bioinformatics (G.W., E.R., J.M.), St. Jude Children's Research Hospital, Memphis, TN; Department of Neuroscience (M.v.B.), Mayo Clinic, Jacksonville, FL; Department of Neurology (J.W., A.C., M.B.), University of Miami, FL; Center for Molecular Neurology (R.R.), University of Antwerp, Belguim; Department of Cell and Molecular Biology (J.P.T.), St. Jude Children's Research Hospital, Memphis, TN; and Neurology (J.M.H.), Department of Medicine, University of Cape Town, South Africa
| | - Gang Wu
- Neurology Research Group (M.N., A.C.M., N.M., J.M.H.), Neuroscience Institute, University of Cape Town; Computational Biology Division (M.N., A.C.M., N.M., G.R.B., N.J.M.), Institute of Infectious Disease and Molecular Medicine, Cape Town, South Africa; Center for Applied Bioinformatics (G.W., E.R., J.M.), St. Jude Children's Research Hospital, Memphis, TN; Department of Neuroscience (M.v.B.), Mayo Clinic, Jacksonville, FL; Department of Neurology (J.W., A.C., M.B.), University of Miami, FL; Center for Molecular Neurology (R.R.), University of Antwerp, Belguim; Department of Cell and Molecular Biology (J.P.T.), St. Jude Children's Research Hospital, Memphis, TN; and Neurology (J.M.H.), Department of Medicine, University of Cape Town, South Africa
| | - Evadnie Rampersaud
- Neurology Research Group (M.N., A.C.M., N.M., J.M.H.), Neuroscience Institute, University of Cape Town; Computational Biology Division (M.N., A.C.M., N.M., G.R.B., N.J.M.), Institute of Infectious Disease and Molecular Medicine, Cape Town, South Africa; Center for Applied Bioinformatics (G.W., E.R., J.M.), St. Jude Children's Research Hospital, Memphis, TN; Department of Neuroscience (M.v.B.), Mayo Clinic, Jacksonville, FL; Department of Neurology (J.W., A.C., M.B.), University of Miami, FL; Center for Molecular Neurology (R.R.), University of Antwerp, Belguim; Department of Cell and Molecular Biology (J.P.T.), St. Jude Children's Research Hospital, Memphis, TN; and Neurology (J.M.H.), Department of Medicine, University of Cape Town, South Africa
| | - Marka van Blitterswijk
- Neurology Research Group (M.N., A.C.M., N.M., J.M.H.), Neuroscience Institute, University of Cape Town; Computational Biology Division (M.N., A.C.M., N.M., G.R.B., N.J.M.), Institute of Infectious Disease and Molecular Medicine, Cape Town, South Africa; Center for Applied Bioinformatics (G.W., E.R., J.M.), St. Jude Children's Research Hospital, Memphis, TN; Department of Neuroscience (M.v.B.), Mayo Clinic, Jacksonville, FL; Department of Neurology (J.W., A.C., M.B.), University of Miami, FL; Center for Molecular Neurology (R.R.), University of Antwerp, Belguim; Department of Cell and Molecular Biology (J.P.T.), St. Jude Children's Research Hospital, Memphis, TN; and Neurology (J.M.H.), Department of Medicine, University of Cape Town, South Africa
| | - Joanne Wuu
- Neurology Research Group (M.N., A.C.M., N.M., J.M.H.), Neuroscience Institute, University of Cape Town; Computational Biology Division (M.N., A.C.M., N.M., G.R.B., N.J.M.), Institute of Infectious Disease and Molecular Medicine, Cape Town, South Africa; Center for Applied Bioinformatics (G.W., E.R., J.M.), St. Jude Children's Research Hospital, Memphis, TN; Department of Neuroscience (M.v.B.), Mayo Clinic, Jacksonville, FL; Department of Neurology (J.W., A.C., M.B.), University of Miami, FL; Center for Molecular Neurology (R.R.), University of Antwerp, Belguim; Department of Cell and Molecular Biology (J.P.T.), St. Jude Children's Research Hospital, Memphis, TN; and Neurology (J.M.H.), Department of Medicine, University of Cape Town, South Africa
| | - Anne Cooley
- Neurology Research Group (M.N., A.C.M., N.M., J.M.H.), Neuroscience Institute, University of Cape Town; Computational Biology Division (M.N., A.C.M., N.M., G.R.B., N.J.M.), Institute of Infectious Disease and Molecular Medicine, Cape Town, South Africa; Center for Applied Bioinformatics (G.W., E.R., J.M.), St. Jude Children's Research Hospital, Memphis, TN; Department of Neuroscience (M.v.B.), Mayo Clinic, Jacksonville, FL; Department of Neurology (J.W., A.C., M.B.), University of Miami, FL; Center for Molecular Neurology (R.R.), University of Antwerp, Belguim; Department of Cell and Molecular Biology (J.P.T.), St. Jude Children's Research Hospital, Memphis, TN; and Neurology (J.M.H.), Department of Medicine, University of Cape Town, South Africa
| | - Jason Myers
- Neurology Research Group (M.N., A.C.M., N.M., J.M.H.), Neuroscience Institute, University of Cape Town; Computational Biology Division (M.N., A.C.M., N.M., G.R.B., N.J.M.), Institute of Infectious Disease and Molecular Medicine, Cape Town, South Africa; Center for Applied Bioinformatics (G.W., E.R., J.M.), St. Jude Children's Research Hospital, Memphis, TN; Department of Neuroscience (M.v.B.), Mayo Clinic, Jacksonville, FL; Department of Neurology (J.W., A.C., M.B.), University of Miami, FL; Center for Molecular Neurology (R.R.), University of Antwerp, Belguim; Department of Cell and Molecular Biology (J.P.T.), St. Jude Children's Research Hospital, Memphis, TN; and Neurology (J.M.H.), Department of Medicine, University of Cape Town, South Africa
| | - Rosa Rademakers
- Neurology Research Group (M.N., A.C.M., N.M., J.M.H.), Neuroscience Institute, University of Cape Town; Computational Biology Division (M.N., A.C.M., N.M., G.R.B., N.J.M.), Institute of Infectious Disease and Molecular Medicine, Cape Town, South Africa; Center for Applied Bioinformatics (G.W., E.R., J.M.), St. Jude Children's Research Hospital, Memphis, TN; Department of Neuroscience (M.v.B.), Mayo Clinic, Jacksonville, FL; Department of Neurology (J.W., A.C., M.B.), University of Miami, FL; Center for Molecular Neurology (R.R.), University of Antwerp, Belguim; Department of Cell and Molecular Biology (J.P.T.), St. Jude Children's Research Hospital, Memphis, TN; and Neurology (J.M.H.), Department of Medicine, University of Cape Town, South Africa
| | - J Paul Taylor
- Neurology Research Group (M.N., A.C.M., N.M., J.M.H.), Neuroscience Institute, University of Cape Town; Computational Biology Division (M.N., A.C.M., N.M., G.R.B., N.J.M.), Institute of Infectious Disease and Molecular Medicine, Cape Town, South Africa; Center for Applied Bioinformatics (G.W., E.R., J.M.), St. Jude Children's Research Hospital, Memphis, TN; Department of Neuroscience (M.v.B.), Mayo Clinic, Jacksonville, FL; Department of Neurology (J.W., A.C., M.B.), University of Miami, FL; Center for Molecular Neurology (R.R.), University of Antwerp, Belguim; Department of Cell and Molecular Biology (J.P.T.), St. Jude Children's Research Hospital, Memphis, TN; and Neurology (J.M.H.), Department of Medicine, University of Cape Town, South Africa
| | - Michael Benatar
- Neurology Research Group (M.N., A.C.M., N.M., J.M.H.), Neuroscience Institute, University of Cape Town; Computational Biology Division (M.N., A.C.M., N.M., G.R.B., N.J.M.), Institute of Infectious Disease and Molecular Medicine, Cape Town, South Africa; Center for Applied Bioinformatics (G.W., E.R., J.M.), St. Jude Children's Research Hospital, Memphis, TN; Department of Neuroscience (M.v.B.), Mayo Clinic, Jacksonville, FL; Department of Neurology (J.W., A.C., M.B.), University of Miami, FL; Center for Molecular Neurology (R.R.), University of Antwerp, Belguim; Department of Cell and Molecular Biology (J.P.T.), St. Jude Children's Research Hospital, Memphis, TN; and Neurology (J.M.H.), Department of Medicine, University of Cape Town, South Africa
| | - Jeannine M Heckmann
- Neurology Research Group (M.N., A.C.M., N.M., J.M.H.), Neuroscience Institute, University of Cape Town; Computational Biology Division (M.N., A.C.M., N.M., G.R.B., N.J.M.), Institute of Infectious Disease and Molecular Medicine, Cape Town, South Africa; Center for Applied Bioinformatics (G.W., E.R., J.M.), St. Jude Children's Research Hospital, Memphis, TN; Department of Neuroscience (M.v.B.), Mayo Clinic, Jacksonville, FL; Department of Neurology (J.W., A.C., M.B.), University of Miami, FL; Center for Molecular Neurology (R.R.), University of Antwerp, Belguim; Department of Cell and Molecular Biology (J.P.T.), St. Jude Children's Research Hospital, Memphis, TN; and Neurology (J.M.H.), Department of Medicine, University of Cape Town, South Africa
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Mesaros M, Lenz S, Lim W, Brown J, Drury L, Roggenbuck J. Investigating the Genetic Profile of the Amyotrophic Lateral Sclerosis/Frontotemporal Dementia (ALS-FTD) Continuum in Patients of Diverse Race, Ethnicity and Ancestry. Genes (Basel) 2021; 13:genes13010076. [PMID: 35052416 PMCID: PMC8775163 DOI: 10.3390/genes13010076] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2021] [Revised: 12/20/2021] [Accepted: 12/21/2021] [Indexed: 11/24/2022] Open
Abstract
Preliminary evidence suggests that commonly used genetic tests may be less likely to identify a genetic etiology for ALS-FTD in patients of underrepresented race, ethnicity, and ancestry (REA), as compared to European REA. Patients of underrepresented REA may therefore be less likely to receive accurate and specific genetic counseling information and less likely to have access to gene-targeted therapies currently in clinical trials. We compiled outcome data from 1911 ALS-FTD patients tested at a commercial laboratory over a seven-year period for C9orf72 hexanucleotide repeat expansion (HRE) alone or C9orf72 and multigene sequencing panel testing. We compared the incidence of pathogenic (P), likely pathogenic (LP), and uncertain variants in C9orf72 and other ALS-FTD genes, as well as age at testing, in patients of different REA. The diagnostic rate in patients of European REA (377/1595, 23.64%) was significantly higher than in patients of underrepresented REA (44/316, 13.92%) (p < 0.001). Patients of European REA were more likely to have the C9orf72 HRE (21.3%) than patients of underrepresented REA (10.4%) (p < 0.001). The overall distribution of positive test outcomes in all tested genes was significantly different between the two groups, with relatively more P and LP variants in genes other than C9orf72 identified in patients of underrepresented REA. The incidence of uncertain test outcomes was not significantly different between patients of European and underrepresented REA. Patients with positive test outcomes were more likely to be younger than those with negative or uncertain outcomes. Although C9orf72 HRE assay has been advocated as the first, and in some cases, only genetic test offered to patients with ALS-FTD in the clinical setting, this practice may result in the reduced ascertainment of genetic ALS-FTD in patients of diverse REA.
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Affiliation(s)
- Maysen Mesaros
- Department of Internal Medicine, The Ohio State University Wexner Medical Center, Columbus, OH 43212, USA; (J.B.); (J.R.)
- Division of Neuroscience, Medical University of South Carolina, Charleston, SC 29425, USA
- Correspondence:
| | - Steven Lenz
- PreventionGenetics, Marshfield, WI 54449, USA; (S.L.); (L.D.)
| | - Woobeen Lim
- Division of Biostatistics, College of Public Health, The Ohio State University, Columbus, OH 43210, USA;
| | - Jordan Brown
- Department of Internal Medicine, The Ohio State University Wexner Medical Center, Columbus, OH 43212, USA; (J.B.); (J.R.)
| | - Luke Drury
- PreventionGenetics, Marshfield, WI 54449, USA; (S.L.); (L.D.)
| | - Jennifer Roggenbuck
- Department of Internal Medicine, The Ohio State University Wexner Medical Center, Columbus, OH 43212, USA; (J.B.); (J.R.)
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12
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Nel M, Mavundla T, Gultig K, Botha G, Mulder N, Benatar M, Wuu J, Cooley A, Myers J, Rampersaud E, Wu G, Heckmann JM. Repeats expansions in ATXN2, NOP56, NIPA1 and ATXN1 are not associated with ALS in Africans. IBRO Neurosci Rep 2021; 10:130-135. [PMID: 34179866 PMCID: PMC8211917 DOI: 10.1016/j.ibneur.2021.02.002] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2020] [Accepted: 02/03/2021] [Indexed: 01/04/2023] Open
Abstract
Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease characterized primarily by progressive loss of motor neurons. Although ALS occurs worldwide and the frequency and spectrum of identifiable genetic causes of disease varies across populations, very few studies have included African subjects. In addition to a hexanucleotide repeat expansion (RE) in C9orf72, the most common genetic cause of ALS in Europeans, REs in ATXN2, NIPA1 and ATXN1 have shown variable associations with ALS in Europeans. Intermediate range expansions in some of these genes (e.g. ATXN2) have been reported as potential risk factors, or phenotypic modifiers, of ALS. Pathogenic expansions in NOP56 cause spinocerebellar ataxia-36, which can present with prominent motor neuron degeneration. Here we compare REs in these genes in a cohort of Africans with ALS and population controls using whole genome sequencing data. Targeting genotyping of short tandem repeats at known loci within ATXN2, NIPA1, ATXN1 and NOP56 was performed using ExpansionHunter software in 105 Southern African (SA) patients with ALS. African population controls were from an in-house SA population control database (n = 25), the SA Human Genome Program (n = 24), the Simons Genome Diversity Project (n = 39) and the Illumina Polaris Diversity Cohort (IPDC) dataset (n = 50). We found intermediate RE alleles in ATXN2 (27-33 repeats) and ATXN1 (33-35 repeats), and NIPA1 long alleles (≥8 repeats) were rare in Africans, and not associated with ALS (p > 0.17). NOP56 showed no expanded alleles in either ALS or controls. We also compared the differences in allele distributions between the African and n = 50 European controls (from the IPDC). There was a statistical significant difference in the distribution of the REs in the ATXN1 between African and European controls (Chi-test p < 0.001), and NIPA1 showed proportionately more longer alleles (RE > 8) in Europeans vs. Africans (Fisher's p = 0.016). The distribution of RE alleles in ATXN2 and NOP56 were similar amongst African and European controls. In conclusion, repeat expansions in ATXN2, NIPA1 and ATXN1, which showed associations with ALS in Europeans, were not replicated in Southern Africans with ALS.
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Affiliation(s)
- Melissa Nel
- Neurology Research Group, Neuroscience Institute, University of Cape Town, Cape Town, South Africa
- Computational Biology Division, Institute of Infectious Disease and Molecular Medicine, South Africa
| | - Thandeka Mavundla
- Neurology Research Group, Neuroscience Institute, University of Cape Town, Cape Town, South Africa
- Computational Biology Division, Institute of Infectious Disease and Molecular Medicine, South Africa
| | - Kayleigh Gultig
- Neurology Research Group, Neuroscience Institute, University of Cape Town, Cape Town, South Africa
| | - Gerrit Botha
- Computational Biology Division, Institute of Infectious Disease and Molecular Medicine, South Africa
| | - Nicola Mulder
- Computational Biology Division, Institute of Infectious Disease and Molecular Medicine, South Africa
| | - Michael Benatar
- Department of Neurology, University of Miami, Miami, FL, USA
| | - Joanne Wuu
- Department of Neurology, University of Miami, Miami, FL, USA
| | - Anne Cooley
- Department of Neurology, University of Miami, Miami, FL, USA
| | - Jason Myers
- Center for Applied Bioinformatics, St Jude Children’s Research Hospital, Memphis, USA
| | - Evadnie Rampersaud
- Center for Applied Bioinformatics, St Jude Children’s Research Hospital, Memphis, USA
| | - Gang Wu
- Center for Applied Bioinformatics, St Jude Children’s Research Hospital, Memphis, USA
| | - Jeannine M. Heckmann
- Neurology Research Group, Neuroscience Institute, University of Cape Town, Cape Town, South Africa
- Neurology division, Department of Medicine, University of Cape Town, Cape Town, South Africa
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13
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Henning F, Heckmann JM, Naidu K, Vlok L, Cross HM, Marin B. Incidence of motor neuron disease/amyotrophic lateral sclerosis in South Africa: a 4-year prospective study. Eur J Neurol 2020; 28:81-89. [PMID: 32888367 DOI: 10.1111/ene.14499] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2020] [Accepted: 08/26/2020] [Indexed: 12/12/2022]
Abstract
BACKGROUND AND PURPOSE Little is known about the epidemiological features of amyotrophic lateral sclerosis (ALS) in sub-Saharan Africa, and data from the region are limited to clinical series or case reports. The aim of the study was to investigate the incidence rate and presentation of ALS in an ethnically diverse region of South Africa. METHODS We performed a 4-year prospective incidence study in the Western Cape Province of South Africa between 1 July 2014 and 30 June 2018, and used a two-source capture-recapture method for case ascertainment. Age- and sex-adjusted incidence rates (ASAIRs) were calculated using the 2010 US population as the reference. RESULTS A total of 203 incident cases were identified over the study period, resulting in a crude incidence rate (IR) of 1.09 [95% confidence interval (CI) 0.94-1.24] per 100 000 person-years in the at-risk population (aged >15 years). Capture-recapture analysis resulted in an estimated IR of 1.11 (95% CI 1.01-1.22) per 100 000 person-years. The ASAIR was 1.67 (95% CI 1.09-2.26) overall; 1.99 (95% CI 1.60-2.39) for men and 1.37 (95% CI 1.06-1.68) for women. When analysed separately, there was a substantial difference in ASAIRs between the different population groups, with the highest in the European ancestry group (2.62; 95% CI 2.49-2.75), the lowest in the African ancestry group (0.56, 95% CI 0.0-1.23), and an ASAIR in between these two in the mixed ancestry group (1.09, 95% CI 0.80-1.37). CONCLUSION The overall incidence of ALS in the Western Cape Province of South Africa appears to be lower than in North African and Western countries, but higher than in Asian countries. As suggested by previous epidemiological studies, ALS may be less frequent in people of African ancestry.
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Affiliation(s)
- F Henning
- Division of Neurology, Department of Medicine, Faculty of Medicine and Health Sciences, Stellenbosch University, Cape Town, South Africa
| | - J M Heckmann
- Division of Neurology, Department of Medicine, Faculty of Health Sciences, University of Cape Town, Cape Town, South Africa
| | - K Naidu
- Division of Neurology, Department of Medicine, Faculty of Medicine and Health Sciences, Stellenbosch University, Cape Town, South Africa
| | - L Vlok
- Division of Neurology, Department of Medicine, Faculty of Medicine and Health Sciences, Stellenbosch University, Cape Town, South Africa
| | - H M Cross
- Division of Neurology, Department of Medicine, Faculty of Health Sciences, University of Cape Town, Cape Town, South Africa
| | - B Marin
- Ministere de la Sante et des Solidarites, Cellule Interministérielle Recherche MSS/MESRI, Paris, France
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