1
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Cook SL, Stout C, Kirkeby L, Vidal-Folch N, Oglesbee D, Hasadsri L, Selcen D, Milone M, Anderson D, Staff NP. SMN1 c.5C>G (p.Ala2Gly) missense variant, a challenging molecular SMA diagnosis associated with mild disease, preserves SMN nuclear gems in patient-specific fibroblasts. Front Genet 2024; 15:1406819. [PMID: 39139818 PMCID: PMC11319185 DOI: 10.3389/fgene.2024.1406819] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2024] [Accepted: 06/25/2024] [Indexed: 08/15/2024] Open
Abstract
Introduction Spinal muscular atrophy (SMA) is caused by homozygous loss of the SMN1 gene with SMN2 gene copy number correlating with disease severity. Rarely SMA is caused by a deletion on one allele and a pathogenic variant on the other. The pathogenic missense variant c.5C>G (p.Ala2Gly) correlates with a mild disease phenotype that does not correlate with SMN2 copy number. In a mouse model the c.5C>G transgene produces SMN that is thought to form partially functional SMN complexes, but levels in humans have not yet been investigated. Methods We identified two patients with mild SMA caused by a heterozygous deletion of SMN1 and the heterozygous variant, c.5C>G. Molecular findings were confirmed with deletion/duplication analysis and Sanger sequencing. Skin fibroblasts were collected and cultured, and SMN expression was analyzed using immunofluorescence. Results Two patients with slowly progressing mild weakness were confirmed to have heterozygous pathogenic missense variant c.5C>G and a heterozygous deletion of SMN1. Their clinical presentation revealed much milder disease progression than patients with matched SMN2 copy number. Analysis of the patients' fibroblasts revealed much higher numbers of SMN nuclear complexes than a patient with a homozygous SMN1 deletion and matched SMN2 copy number. Conclusions These case reports reinforce that the rare c.5C>G variant causes mild disease. Furthermore, the analysis of SMA nuclear gems in patient samples supports the theory that the p.Ala2Gly SMN can form partially functional SMN complexes that may carry out essential cellular functions and result in mild disease.
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Affiliation(s)
- Sara L. Cook
- Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, MN, United States
| | - Christian Stout
- Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, MN, United States
| | - Lindsey Kirkeby
- Center for Regenerative Medicine, Mayo Clinic, Rochester, MN, United States
| | - Noemi Vidal-Folch
- Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, MN, United States
| | - Devin Oglesbee
- Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, MN, United States
| | - Linda Hasadsri
- Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, MN, United States
| | - Duygu Selcen
- Department of Neurology, Mayo Clinic, Rochester, MN, United States
| | | | - Daniel Anderson
- Department of Neurology, Mayo Clinic Health System, La Crosse, WI, United States
| | - Nathan P. Staff
- Department of Neurology, Mayo Clinic, Rochester, MN, United States
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2
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Grass T, Dokuzluoglu Z, Buchner F, Rosignol I, Thomas J, Caldarelli A, Dalinskaya A, Becker J, Rost F, Marass M, Wirth B, Beyer M, Bonaguro L, Rodriguez-Muela N. Isogenic patient-derived organoids reveal early neurodevelopmental defects in spinal muscular atrophy initiation. Cell Rep Med 2024:101659. [PMID: 39067446 DOI: 10.1016/j.xcrm.2024.101659] [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: 07/25/2023] [Revised: 02/26/2024] [Accepted: 07/02/2024] [Indexed: 07/30/2024]
Abstract
Whether neurodevelopmental defects underlie postnatal neuronal death in neurodegeneration is an intriguing hypothesis only recently explored. Here, we focus on spinal muscular atrophy (SMA), a neuromuscular disorder caused by reduced survival of motor neuron (SMN) protein levels leading to spinal motor neuron (MN) loss and muscle wasting. Using the first isogenic patient-derived induced pluripotent stem cell (iPSC) model and a spinal cord organoid (SCO) system, we show that SMA SCOs exhibit abnormal morphological development, reduced expression of early neural progenitor markers, and accelerated expression of MN progenitor and MN markers. Longitudinal single-cell RNA sequencing reveals marked defects in neural stem cell specification and fewer MNs, favoring mesodermal progenitors and muscle cells, a bias also seen in early SMA mouse embryos. Surprisingly, SMN2-to-SMN1 conversion does not fully reverse these developmental abnormalities. These suggest that early neurodevelopmental defects may underlie later MN degeneration, indicating that postnatal SMN-increasing interventions might not completely amend SMA pathology in all patients.
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Affiliation(s)
- Tobias Grass
- German Center for Neurodegenerative Diseases e.V. (DZNE), Dresden, Germany.
| | - Zeynep Dokuzluoglu
- German Center for Neurodegenerative Diseases e.V. (DZNE), Dresden, Germany
| | - Felix Buchner
- German Center for Neurodegenerative Diseases e.V. (DZNE), Dresden, Germany
| | - Ines Rosignol
- German Center for Neurodegenerative Diseases e.V. (DZNE), Dresden, Germany; Technische Universität Dresden (TUD), Center for Regenerative Therapies Dresden, Dresden, Germany
| | - Joshua Thomas
- German Center for Neurodegenerative Diseases e.V. (DZNE), Dresden, Germany
| | - Antonio Caldarelli
- German Center for Neurodegenerative Diseases e.V. (DZNE), Dresden, Germany
| | - Anna Dalinskaya
- German Center for Neurodegenerative Diseases e.V. (DZNE), Dresden, Germany
| | - Jutta Becker
- Institute of Human Genetics, University Hospital of Cologne, Cologne, Germany
| | - Fabian Rost
- DRESDEN-concept Genome Center, Technology Platform at the Center for Molecular and Cellular Bioengineering, TUD, Dresden, Germany
| | - Michele Marass
- Max Planck Institute for Molecular Cell Biology and Genetics, Dresden, Germany; Center for Systems Biology Dresden, Dresden, Germany
| | - Brunhilde Wirth
- Institute of Human Genetics, University Hospital of Cologne, Cologne, Germany; Center for Molecular Medicine Cologne, University of Cologne, Cologne, Germany; Center for Rare Diseases, University Hospital of Cologne, Cologne, Germany
| | - Marc Beyer
- Systems Medicine, DZNE, Bonn, Germany; PRECISE Platform for Single Cell Genomics and Epigenomics, DZNE & University of Bonn and West German Genome Center, Bonn, Germany; Immunogenomics & Neurodegeneration, DZNE, Bonn, Germany
| | - Lorenzo Bonaguro
- Systems Medicine, DZNE, Bonn, Germany; Genomics & Immunoregulation, LIMES Institute, University of Bonn, Bonn, Germany
| | - Natalia Rodriguez-Muela
- German Center for Neurodegenerative Diseases e.V. (DZNE), Dresden, Germany; Technische Universität Dresden (TUD), Center for Regenerative Therapies Dresden, Dresden, Germany; Max Planck Institute for Molecular Cell Biology and Genetics, Dresden, Germany.
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3
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Weisburd B, Sharma R, Pata V, Reimand T, Ganesh VS, Austin-Tse C, Osei-Owusu I, O’Heir E, O’Leary M, Pais L, Stafki SA, Daugherty AL, Folland C, Perić S, Fahmy N, Udd B, Horakova M, Łusakowska A, Manoj R, Nalini A, Karcagi V, Polavarapu K, Lochmüller H, Horvath R, Bönnemann CG, Donkervoort S, Haliloğlu G, Herguner O, Kang PB, Ravenscroft G, Laing N, Scott HS, Töpf A, Straub V, Pajusalu S, Õunap K, Tiao G, Rehm HL, O’Donnell-Luria A. Diagnosing missed cases of spinal muscular atrophy in genome, exome, and panel sequencing datasets. MEDRXIV : THE PREPRINT SERVER FOR HEALTH SCIENCES 2024:2024.02.11.24302646. [PMID: 38405995 PMCID: PMC10889006 DOI: 10.1101/2024.02.11.24302646] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/27/2024]
Abstract
Spinal muscular atrophy (SMA) is a genetic disorder that causes progressive degeneration of lower motor neurons and the subsequent loss of muscle function throughout the body. It is the second most common recessive disorder in individuals of European descent and is present in all populations. Accurate tools exist for diagnosing SMA from genome sequencing data. However, there are no publicly available tools for GRCh38-aligned data from panel or exome sequencing assays which continue to be used as first line tests for neuromuscular disorders. This deficiency creates a critical gap in our ability to diagnose SMA in large existing rare disease cohorts, as well as newly sequenced exome and panel datasets. We therefore developed and extensively validated a new tool - SMA Finder - that can diagnose SMA not only in genome, but also exome and panel sequencing samples aligned to GRCh37, GRCh38, or T2T-CHM13. It works by evaluating aligned reads that overlap the c.840 position of SMN1 and SMN2 in order to detect the most common molecular causes of SMA. We applied SMA Finder to 16,626 exomes and 3,911 genomes from heterogeneous rare disease cohorts sequenced at the Broad Institute Center for Mendelian Genomics as well as 1,157 exomes and 8,762 panel sequencing samples from Tartu University Hospital. SMA Finder correctly identified all 16 known SMA cases and reported nine novel diagnoses which have since been confirmed by clinical testing, with another four novel diagnoses undergoing validation. Notably, out of the 29 total SMA positive cases, 23 had an initial clinical diagnosis of muscular dystrophy, congenital myasthenic syndrome, or myopathy. This underscored the frequency with which SMA can be misdiagnosed as other neuromuscular disorders and confirmed the utility of using SMA Finder to reanalyze phenotypically diverse neuromuscular disease cohorts. Finally, we evaluated SMA Finder on 198,868 individuals that had both exome and genome sequencing data within the UK Biobank (UKBB) and found that SMA Finder's overall false positive rate was less than 1 / 200,000 exome samples, and its positive predictive value (PPV) was 97%. We also observed 100% concordance between UKBB exome and genome calls. This analysis showed that, even though it is located within a segmental duplication, the most common causal variant for SMA can be detected with comparable accuracy to monogenic disease variants in non-repetitive regions. Additionally, the high PPV demonstrated by SMA Finder, the existence of treatment options for SMA in which early diagnosis is imperative for therapeutic benefit, as well as widespread availability of clinical confirmatory testing for SMA, warrants the addition of SMN1 to the ACMG list of genes with reportable secondary findings after genome and exome sequencing.
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Affiliation(s)
- Ben Weisburd
- Program in Medical and Population Genetics, Broad Institute of MIT and Harvard, Cambridge, MA, USA
- Center for Genomic Medicine, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - Rakshya Sharma
- Program in Medical and Population Genetics, Broad Institute of MIT and Harvard, Cambridge, MA, USA
- UC Santa Cruz Genomics Institute, UCSC, Santa Cruz, CA, USA
| | - Villem Pata
- Department of Clinical Genetics, Institute of Clinical Medicine, University of Tartu, Tartu, Estonia
- Anesthesiology and Intensive Care Clinic, Tartu University Hospital, Tartu, Estonia
| | - Tiia Reimand
- Department of Clinical Genetics, Institute of Clinical Medicine, University of Tartu, Tartu, Estonia
- Genetics and Personalized Medicine Clinic, Tartu University Hospital, Tartu, Estonia
| | - Vijay S. Ganesh
- Program in Medical and Population Genetics, Broad Institute of MIT and Harvard, Cambridge, MA, USA
- Center for Genomic Medicine, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
- Department of Neurology, Brigham & Women’s Hospital,Boston, MA, USA
- Division of Genetics and Genomics, Boston Children’s Hospital, Harvard Medical School, Boston, MA, USA
| | - Christina Austin-Tse
- Program in Medical and Population Genetics, Broad Institute of MIT and Harvard, Cambridge, MA, USA
- Center for Genomic Medicine, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - Ikeoluwa Osei-Owusu
- Program in Medical and Population Genetics, Broad Institute of MIT and Harvard, Cambridge, MA, USA
- Division of Genetics and Genomics, Boston Children’s Hospital, Harvard Medical School, Boston, MA, USA
| | - Emily O’Heir
- Program in Medical and Population Genetics, Broad Institute of MIT and Harvard, Cambridge, MA, USA
- Division of Genetics and Genomics, Boston Children’s Hospital, Harvard Medical School, Boston, MA, USA
| | - Melanie O’Leary
- Program in Medical and Population Genetics, Broad Institute of MIT and Harvard, Cambridge, MA, USA
| | - Lynn Pais
- Program in Medical and Population Genetics, Broad Institute of MIT and Harvard, Cambridge, MA, USA
- Division of Genetics and Genomics, Boston Children’s Hospital, Harvard Medical School, Boston, MA, USA
| | - Seth A. Stafki
- Greg Marzolf Jr. Muscular Dystrophy Center, Department of Neurology, and Institute for Translational Neuroscience, University of Minnesota, Minneapolis, MN, USA
| | - Audrey L. Daugherty
- Greg Marzolf Jr. Muscular Dystrophy Center, Department of Neurology, and Institute for Translational Neuroscience, University of Minnesota, Minneapolis, MN, USA
| | - Chiara Folland
- Centre of Medical Research, The University of Western Australia, Perth, Western Australia, Australia
| | - Stojan Perić
- University of Belgrade, Faculty of Medicine, Belgrade, Serbia
- University Clinical Centre of Serbia, Neurology Clinic, Belgrade, Serbia
| | - Nagia Fahmy
- Neuromuscular Center, Ain Shams University, Cairo, Egypt
| | - Bjarne Udd
- Tampere Neuromuscular Center and Folkhalsan Research Center, Helsinki, Finland
| | - Magda Horakova
- Department of Neurology, Neuromuscular Center ERN, University Hospital Brno, Brno, Czech Republic
- Faculty of Medicine, Masaryk University, Brno, Czech Republic
| | - Anna Łusakowska
- Department of Neurology, Medical University of Warsaw, Warsaw, Poland
| | - Rajanna Manoj
- National Institute of Mental Health and Neuro Sciences, Bengaluru, India
| | - Atchayaram Nalini
- National Institute of Mental Health and Neuro Sciences, Bengaluru, India
| | - Veronika Karcagi
- Istenhegyi Genetic Diagnostic Centre, Molecular Genetic Laboratory, Budapest, Hungary
| | - Kiran Polavarapu
- Children’s Hospital of Eastern Ontario Research Institute, Ottawa, ON, Canada
| | - Hanns Lochmüller
- Children’s Hospital of Eastern Ontario Research Institute, Ottawa, ON, Canada
- Division of Neurology, Department of Medicine, The Ottawa Hospital, Ottawa, ON, Canada
- Brain and Mind Research Institute, University of Ottawa, Ottawa, ON, Canada
| | - Rita Horvath
- Department of Clinical Neurosciences, University of Cambridge, Cambridge, UK
| | - Carsten G. Bönnemann
- Neuromuscular and Neurogenetic Disorders of Childhood Section, Neurogenetics Branch, National Institute of Neurological Disorders and Stroke, NIH, Bethesda, MD, USA
| | - Sandra Donkervoort
- Neuromuscular and Neurogenetic Disorders of Childhood Section, Neurogenetics Branch, National Institute of Neurological Disorders and Stroke, NIH, Bethesda, MD, USA
| | - Göknur Haliloğlu
- Neuromuscular and Neurogenetic Disorders of Childhood Section, Neurogenetics Branch, National Institute of Neurological Disorders and Stroke, NIH, Bethesda, MD, USA
- Division of Pediatric Neurology, Department of Pediatrics, Hacettepe University Faculty of Medicine, Ankara, Turkey
| | - Ozlem Herguner
- Çukurova University Faculty of Medicine, Department of Pediatrics, Division of Pediatric Neurology, Adana, Turkey
| | - Peter B. Kang
- Greg Marzolf Jr. Muscular Dystrophy Center, Department of Neurology, and Institute for Translational Neuroscience, University of Minnesota, Minneapolis, MN, USA
| | - Gianina Ravenscroft
- Centre of Medical Research, The University of Western Australia, Perth, Western Australia, Australia
- Harry Perkins Institute for Medical Research, Perth, Western Australia, Australia
| | - Nigel Laing
- Centre of Medical Research, The University of Western Australia, Perth, Western Australia, Australia
- Harry Perkins Institute for Medical Research, Perth, Western Australia, Australia
| | - Hamish S. Scott
- Centre for Cancer Biology, An SA Pathology & UniSA Alliance, Adelaide, SA, Australia
| | - Ana Töpf
- John Walton Muscular Dystrophy Research Centre, Newcastle University and Newcastle Hospitals NHS Foundation Trust, Newcastle upon Tyne, UK
| | - Volker Straub
- John Walton Muscular Dystrophy Research Centre, Newcastle University and Newcastle Hospitals NHS Foundation Trust, Newcastle upon Tyne, UK
| | - Sander Pajusalu
- Department of Clinical Genetics, Institute of Clinical Medicine, University of Tartu, Tartu, Estonia
- Genetics and Personalized Medicine Clinic, Tartu University Hospital, Tartu, Estonia
| | - Katrin Õunap
- Department of Clinical Genetics, Institute of Clinical Medicine, University of Tartu, Tartu, Estonia
- Genetics and Personalized Medicine Clinic, Tartu University Hospital, Tartu, Estonia
| | - Grace Tiao
- Program in Medical and Population Genetics, Broad Institute of MIT and Harvard, Cambridge, MA, USA
| | - Heidi L. Rehm
- Program in Medical and Population Genetics, Broad Institute of MIT and Harvard, Cambridge, MA, USA
- Center for Genomic Medicine, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - Anne O’Donnell-Luria
- Program in Medical and Population Genetics, Broad Institute of MIT and Harvard, Cambridge, MA, USA
- Center for Genomic Medicine, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
- Division of Genetics and Genomics, Boston Children’s Hospital, Harvard Medical School, Boston, MA, USA
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4
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Hanson B, Shaw J, Povarnitsyn N, Bowns B, Young E, Gerrish A, Allen S, Scotchman E, Chitty LS, Chandler NJ. Expanding Access to Noninvasive Prenatal Diagnosis for Monogenic Conditions to Consanguineous Families. Clin Chem 2024; 70:727-736. [PMID: 38592422 DOI: 10.1093/clinchem/hvae023] [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: 11/02/2023] [Accepted: 01/16/2024] [Indexed: 04/10/2024]
Abstract
BACKGROUND Cell-free fetal DNA exists within the maternal bloodstream during pregnancy and provides a means for noninvasive prenatal diagnosis (NIPD). Our accredited clinical service offers definitive NIPD for several autosomal recessive (AR) and X-linked conditions using relative haplotype dosage analysis (RHDO). RHDO involves next-generation sequencing (NGS) of thousands of common single nucleotide polymorphism (SNPs) surrounding the gene of interest in the parents and an affected or unaffected offspring to conduct haplotype phasing of the high- and low-risk alleles. NGS is carried out in parallel on the maternal cell-free DNA, and fetal inheritance is predicted using sensitive dosage calculations performed at sites where the parental genotypes differ. RHDO is not currently offered to consanguineous couples owing to the shared haplotype between parents. Here we test the expansion of RHDO for AR monogenic conditions to include consanguineous couples. METHODS The existing sequential probability ratio test analysis pipeline was modified to apply to SNPs where both parents are heterozygous for the same genotype. Quality control thresholds were developed using 33 nonconsanguineous cases. The performance of the adapted RHDO pipeline was tested on 8 consanguineous cases. RESULTS The correct fetal genotype was predicted by our revised RHDO approach in all conclusive cases with known genotypes (n = 5). Haplotype block classification accuracies of 94.5% and 93.9% were obtained for the nonconsanguineous and consanguineous case cohorts, respectively. CONCLUSIONS Our modified RHDO pipeline correctly predicts the genotype in fetuses from consanguineous families, allowing the potential to expand access to NIPD services for these families.
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Affiliation(s)
- Britt Hanson
- North Thames Genomic Laboratory Hub, Great Ormond Street NHS Foundation Trust, London, United Kingdom
| | - Joe Shaw
- North Thames Genomic Laboratory Hub, Great Ormond Street NHS Foundation Trust, London, United Kingdom
| | - Nikita Povarnitsyn
- North Thames Genomic Laboratory Hub, Great Ormond Street NHS Foundation Trust, London, United Kingdom
| | - Benjamin Bowns
- West Midlands Regional Genetics Laboratory, Birmingham Women's and Children's NHS Foundation Trust, Birmingham, United Kingdom
| | - Elizabeth Young
- West Midlands Regional Genetics Laboratory, Birmingham Women's and Children's NHS Foundation Trust, Birmingham, United Kingdom
| | - Amy Gerrish
- West Midlands Regional Genetics Laboratory, Birmingham Women's and Children's NHS Foundation Trust, Birmingham, United Kingdom
| | - Stephanie Allen
- West Midlands Regional Genetics Laboratory, Birmingham Women's and Children's NHS Foundation Trust, Birmingham, United Kingdom
| | - Elizabeth Scotchman
- North Thames Genomic Laboratory Hub, Great Ormond Street NHS Foundation Trust, London, United Kingdom
| | - Lyn S Chitty
- North Thames Genomic Laboratory Hub, Great Ormond Street NHS Foundation Trust, London, United Kingdom
- Genetic and Genomic Medicine, UCL Great Ormond Street Institute of Child Health, London, United Kingdom
| | - Natalie J Chandler
- North Thames Genomic Laboratory Hub, Great Ormond Street NHS Foundation Trust, London, United Kingdom
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5
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Vill K, Tacke M, König A, Baumann M, Baumgartner M, Steinbach M, Bernert G, Blaschek A, Deschauer M, Flotats-Bastardas M, Friese J, Goldbach S, Gross M, Günther R, Hahn A, Hagenacker T, Hauser E, Horber V, Illsinger S, Johannsen J, Kamm C, Koch JC, Koelbel H, Koehler C, Kolzter K, Lochmüller H, Ludolph A, Mensch A, Meyer Zu Hoerste G, Mueller M, Mueller-Felber W, Neuwirth C, Petri S, Probst-Schendzielorz K, Pühringer M, Steinbach R, Schara-Schmidt U, Schimmel M, Schrank B, Schwartz O, Schlachter K, Schwerin-Nagel A, Schreiber G, Smitka M, Topakian R, Trollmann R, Tuerk M, Theophil M, Rauscher C, Vorgerd M, Walter MC, Weiler M, Weiss C, Wilichowski E, Wurster CD, Wunderlich G, Zeller D, Ziegler A, Kirschner J, Pechmann A. 5qSMA: standardised retrospective natural history assessment in 268 patients with four copies of SMN2. J Neurol 2024; 271:2787-2797. [PMID: 38409538 PMCID: PMC11055798 DOI: 10.1007/s00415-024-12188-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2023] [Revised: 12/29/2023] [Accepted: 01/05/2024] [Indexed: 02/28/2024]
Abstract
Newborn screening for 5qSMA offers the potential for early, ideally pre-symptomatic, therapeutic intervention. However, limited data exist on the outcomes of individuals with 4 copies of SMN2, and there is no consensus within the SMA treatment community regarding early treatment initiation in this subgroup. To provide evidence-based insights into disease progression, we performed a retrospective analysis of 268 patients with 4 copies of SMN2 from the SMArtCARE registry in Germany, Austria and Switzerland. Inclusion criteria required comprehensive baseline data and diagnosis outside of newborn screening. Only data prior to initiation of disease-modifying treatment were included. The median age at disease onset was 3.0 years, with a mean of 6.4 years. Significantly, 55% of patients experienced symptoms before the age of 36 months. 3% never learned to sit unaided, a further 13% never gained the ability to walk independently and 33% of ambulatory patients lost this ability during the course of the disease. 43% developed scoliosis, 6.3% required non-invasive ventilation and 1.1% required tube feeding. In conclusion, our study, in line with previous observations, highlights the substantial phenotypic heterogeneity in SMA. Importantly, this study provides novel insights: the median age of disease onset in patients with 4 SMN2 copies typically occurs before school age, and in half of the patients even before the age of three years. These findings support a proactive approach, particularly early treatment initiation, in this subset of SMA patients diagnosed pre-symptomatically. However, it is important to recognize that the register will not include asymptomatic individuals.
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Affiliation(s)
- Katharina Vill
- Department of Pediatric Neurology and Developmental Medicine and LMU Center for Children With Medical Complexity, Dr. Von Hauner Children's Hospital, LMU Hospital, Ludwig-Maximilians-University, 80337, Munich, Germany.
- School of Medicine, Klinikum Rechts Der Isar, Department of Human Genetics, Technical University of Munich, Munich, Germany.
| | - Moritz Tacke
- Department of Pediatric Neurology and Developmental Medicine and LMU Center for Children With Medical Complexity, Dr. Von Hauner Children's Hospital, LMU Hospital, Ludwig-Maximilians-University, 80337, Munich, Germany
| | - Anna König
- Department of Pediatric Neurology and Developmental Medicine and LMU Center for Children With Medical Complexity, Dr. Von Hauner Children's Hospital, LMU Hospital, Ludwig-Maximilians-University, 80337, Munich, Germany
| | - Matthias Baumann
- Division of Pediatric Neurology, Department of Pediatrics I, Medical University of Innsbruck, Innsbruck, Austria
| | - Manuela Baumgartner
- Department of Children and Adolescents, Ordensklinikum Linz Barmherzige Schwestern, Linz, Austria
| | - Meike Steinbach
- Department of Neurology, University Medical Center Schleswig-Holstein, Kiel, Germany
| | | | - Astrid Blaschek
- Department of Pediatric Neurology and Developmental Medicine and LMU Center for Children With Medical Complexity, Dr. Von Hauner Children's Hospital, LMU Hospital, Ludwig-Maximilians-University, 80337, Munich, Germany
| | - Marcus Deschauer
- School of Medicine, Klinikum Rechts Der Isar, Department of Neurology, Technical University of Munich, Munich, Germany
| | | | - Johannes Friese
- Department of Neuropediatrics, University Hospital Bonn, Center for Pediatrics, Bonn, Germany
| | | | - Martin Gross
- Department of Neurological Intensive Care and Rehabilitation, Evangelisches Krankenhaus Oldenburg, Oldenburg, Germany
| | - René Günther
- University Hospital Carl Gustav Carus Dresden at Technische Universität Dresden, Dresden, Germany
| | - Andreas Hahn
- Department of Child Neurology, Justus-Liebig-University Gießen, Gießen, Germany
| | - Tim Hagenacker
- Department of Neurology, and Center for Translational Neuro- and Behavioral Sciences (C-TNBS), University Medicine Essen, Essen, Germany
| | - Erwin Hauser
- Department for Neuropädiatrie, Landeskrankenhaus Mödling, Mödling, Austria
| | - Veronka Horber
- Department of Paediatric Neurology, University Children's Hospital Tübingen, Tübingen, Germany
| | - Sabine Illsinger
- Hannover Medical School, Clinic for Pediatric Kidney-, Liver- and Metabolic Diseases, Hannover, Germany
| | - Jessika Johannsen
- Department of Pediatrics, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Christoph Kamm
- Department of Neurology, University of Rostock, Rostock, Germany
| | - Jan C Koch
- Klinik Für Neurologie Universitätsmedizin Göttingen, Göttingen, Germany
| | - Heike Koelbel
- Department of Pediatric Neurology, Centre for Neuromuscular Disorders, Centre for Translational Neuro- and Behavioral Sciences, University Duisburg-Essen, Essen, Germany
| | - Cornelia Koehler
- Klinik Für Kinder-Und Jugendmedizin der Ruhr-Universität Bochum Im St. Josef-Hospital, Bochum, Germany
| | - Kirsten Kolzter
- Kliniken Köln, Sozialpädiatrisches Zentrum, Cologne, Germany
| | - Hanns Lochmüller
- Division of Neurology, Department of Medicine, Children's Hospital of Eastern Ontario Research Institute, The Ottawa Hospital and Brain and Mind Research Institute, University of Ottawa, Ottawa, Canada
- Department of Neuropediatrics and Muscle Disorders, Medical Center, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Albert Ludolph
- Department for Neurology, University of Ulm, Ulm, Germany
- Department of Neurology, Ulm University, Ulm, Germany
| | - Alexander Mensch
- Department of Neurology, University Medicine Halle, Halle, Saale, Germany
| | | | - Monika Mueller
- Department for Neuropediatrics, University of Wuerzburg, Würzburg, Germany
| | - Wolfgang Mueller-Felber
- Department of Pediatric Neurology and Developmental Medicine and LMU Center for Children With Medical Complexity, Dr. Von Hauner Children's Hospital, LMU Hospital, Ludwig-Maximilians-University, 80337, Munich, Germany
| | - Christoph Neuwirth
- Neuromuscular Diseases Unit/ALS Clinic, Kantonsspital St. Gallen, St. Gallen, Switzerland
| | - Susanne Petri
- Department of Neurology, Hannover Medical School, Hannover, Germany
| | | | - Manuel Pühringer
- Department of Pediatrics and Adolescent Medicine, Kepler University Hospital Linz, Linz, Austria
| | - Robert Steinbach
- Department of Neurology, University Hospital Jena, Jena, Germany
| | - Ulrike Schara-Schmidt
- Department of Pediatric Neurology, Centre for Neuromuscular Disorders, Centre for Translational Neuro- and Behavioral Sciences, University Duisburg-Essen, Essen, Germany
| | - Mareike Schimmel
- Pediatric Neurology, Pediatrics and Adolescent Medicine, University Medical Center Augsburg, Augsburg, Germany
| | - Bertold Schrank
- Department of Neurology, DKD Helios Klinik Wiesbaden, Wiesbaden, Germany
| | - Oliver Schwartz
- Universitätsklinikum Münster Klinik Für Kinder- Und Jugendpädiatrie- Neuropädiatrie, Albert-Schweitzer-Campus 1, Münster, Germany
| | - Kurt Schlachter
- Department of Neuropediatrics, Landeskrankenhaus Bregenz, Bregenz, Austria
| | | | | | - Martin Smitka
- Department of Neuropediatrics, Medical Faculty Carl Gustav Carus, Technical University Dresden, Dresden, Germany
| | - Raffi Topakian
- Department of Neurology, Academic Teaching Hospital Wels-Grieskirchen, Wels, Austria
| | - Regina Trollmann
- Department of Pediatrics, Friedrich-Alexander Universität Erlangen-Nürnberg Pediatric Neurology, Erlangen, Germany
| | - Matthias Tuerk
- Department of Neurology, University Hospital Erlangen, Friedrich-Alexander University Erlangen-Nuremberg, Erlangen, Germany
- Centre for Rare Diseases Erlangen (ZSEER), University Hospital Erlangen, Friedrich-Alexander University Erlangen-Nuremberg (FAU), Erlangen, Germany
| | | | - Christian Rauscher
- Department for Neuropediatrics, University of Salzburg, Salzburg, Austria
| | - Mathias Vorgerd
- Department of Neurology, BG-University Hospital Bergmannsheil gGmbH, Heimer Institute for Muscle Research, Ruhr-University Bochum, Bochum, Germany
| | - Maggie C Walter
- Friedrich Baur Institute at the Department of Neurology, LMU University Hospital, Ludwig Maximilians University, Munich, Germany
| | - Markus Weiler
- Department of Neurology, Heidelberg University Hospital, Heidelberg, Germany
| | - Claudia Weiss
- Charité - University Medicine Berlin, Center for Chronically Sick Children, Berlin, Germany
| | | | | | - Gilbert Wunderlich
- German Center for Neurodegenerative Diseases, DZNE, Site Ulm, Ulm, Germany
- Faculty of Medicine and University Hospital, Department of Neurology and Center for Rare Diseases, University of Cologne, Cologne, Germany
| | - Daniel Zeller
- Department of Neurology, University Hospital Würzburg, Würzburg, Germany
| | - Andreas Ziegler
- Center for Childhood and Adolescent Medicine, Department of Metabolic Medicine and Pediatric Neurology, University Hospital Heidelberg, Heidelberg, Germany
| | - Janbernd Kirschner
- Klinik Für Kinder-Und Jugendmedizin der Ruhr-Universität Bochum Im St. Josef-Hospital, Bochum, Germany
| | - Astrid Pechmann
- Klinik Für Kinder-Und Jugendmedizin der Ruhr-Universität Bochum Im St. Josef-Hospital, Bochum, Germany
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6
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Shekhawat DS, Didel S, Dixit SG, Singh P, Singh K. Carrier Screening and Diagnosis for Spinal Muscular Atrophy Using Droplet Digital PCR Versus MLPA: Analytical Validation and Early Test Outcome. Genet Test Mol Biomarkers 2024; 28:207-212. [PMID: 38533877 DOI: 10.1089/gtmb.2023.0073] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/28/2024] Open
Abstract
Background: Spinal muscular atrophy (SMA) is an autosomal recessive neuromuscular life-threatening disorder. Owing to high carrier frequency, population-wide SMA screening to quantify the copy number of SMN gene is recommended by American College of Medical Genetics and Genomics. An accurate, reliable, short runaround time and cost-effective method may be helpful in mass population screening for SMA. Methods: Multiplex ligation-dependent probe amplification (MLPA) is a gold standard to estimate the copy number variation (CNV) for SMN1 and SMN2 genes. In this study, we validated droplet digital polymerase chain reaction (ddPCR) for the determination of CNV for both SMN1 and SMN2 exon 7 for a diagnostic purpose. In total, 66 clinical samples were tested using ddPCR, and results were compared with the MLPA as a reference test. Results: For all samples, CNV for SMN1 and SMN2 exon 7 was consentaneous between ddPCR and MLPA test results (κ = 1.000, p < 0.0001). In addition, ddPCR also showed a significant acceptable degree of test repeatability, coefficient of variation < 4%. Conclusion: ddPCR is expected to be utilitarian for CNV detection for carrier screening and diagnosis of SMA. ddPCR test results for CNV detection for SMN1/SMN2 exon 7 are concordant with the gold standard. ddPCR is a more cost-effective and time-saving diagnostic test for SMA than MLPA. Furthermore, it can be used for population-wide carrier screening for SMA.
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Affiliation(s)
- Dolat Singh Shekhawat
- Department of Pediatrics, All India Institute of Medical Science Jodhpur, Jodhpur, Rajasthan, India
- Department of Medical Genetics, All India Institute of Medical Science Jodhpur, Jodhpur, Rajasthan, India
- NIDAN Kendra, Genetic Laboratory, All India Institute of Medical Science Jodhpur, Jodhpur, Rajasthan, India
| | - Siyaram Didel
- Department of Pediatrics, All India Institute of Medical Science Jodhpur, Jodhpur, Rajasthan, India
| | - Shilpi Gupta Dixit
- NIDAN Kendra, Genetic Laboratory, All India Institute of Medical Science Jodhpur, Jodhpur, Rajasthan, India
- Department of Anatomy, All India Institute of Medical Science Jodhpur, Jodhpur, Rajasthan, India
| | - Pratibha Singh
- NIDAN Kendra, Genetic Laboratory, All India Institute of Medical Science Jodhpur, Jodhpur, Rajasthan, India
- Department of Obstetrics & Gynaecology, All India Institute of Medical Science Jodhpur, Jodhpur, Rajasthan, India
| | - Kuldeep Singh
- Department of Pediatrics, All India Institute of Medical Science Jodhpur, Jodhpur, Rajasthan, India
- Department of Medical Genetics, All India Institute of Medical Science Jodhpur, Jodhpur, Rajasthan, India
- NIDAN Kendra, Genetic Laboratory, All India Institute of Medical Science Jodhpur, Jodhpur, Rajasthan, India
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7
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Wang N, Jiao K, He J, Zhu B, Cheng N, Sun J, Chen L, Chen W, Gong L, Qiao K, Xi J, Wu Q, Zhao C, Zhu W. Diagnosis of Challenging Spinal Muscular Atrophy Cases with Long-Read Sequencing. J Mol Diagn 2024; 26:364-373. [PMID: 38490302 DOI: 10.1016/j.jmoldx.2024.02.004] [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: 09/21/2023] [Revised: 01/17/2024] [Accepted: 02/07/2024] [Indexed: 03/17/2024] Open
Abstract
Spinal muscular atrophy (SMA) is an autosomal recessive neuromuscular disorder primarily caused by the deletion or mutation of the survival motor neuron 1 (SMN1) gene. This study assesses the diagnostic potential of long-read sequencing (LRS) in three patients with SMA. For Patient 1, who has a heterozygous SMN1 deletion, LRS unveiled a missense mutation in SMN1 exon 5. In Patient 2, an Alu/Alu-mediated rearrangement covering the SMN1 promoter and exon 1 was identified through a blend of multiplex ligation-dependent probe amplification, LRS, and PCR across the breakpoint. The third patient, born to a consanguineous family, bore four copies of hybrid SMN genes. LRS determined the genomic structures, indicating two distinct hybrids of SMN2 exon 7 and SMN1 exon 8. However, a discrepancy was found between the SMN1/SMN2 ratio interpretations by LRS (0:2) and multiplex ligation-dependent probe amplification (0:4), which suggested a limitation of LRS in SMA diagnosis. In conclusion, this newly adapted long PCR-based third-generation sequencing introduces an additional avenue for SMA diagnosis.
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Affiliation(s)
- Ningning Wang
- Department of Neurology, Huashan Hospital, Fudan University, Shanghai, China; National Center for Neurological Disorders, Shanghai, China; Huashan Rare Disease Center, Huashan Hospital, Shanghai Medical College, Fudan University, Shanghai, China
| | - Kexin Jiao
- Department of Neurology, Huashan Hospital, Fudan University, Shanghai, China; National Center for Neurological Disorders, Shanghai, China; Huashan Rare Disease Center, Huashan Hospital, Shanghai Medical College, Fudan University, Shanghai, China
| | - Jin He
- Department of Neurology and Institute of Neurology of First Affiliated Hospital, Institute of Neuroscience, and Fujian Key Laboratory of Molecular Neurology, Fujian Medical University, Fuzhou, China
| | - Bochen Zhu
- Department of Neurology, Huashan Hospital, Fudan University, Shanghai, China; National Center for Neurological Disorders, Shanghai, China; Huashan Rare Disease Center, Huashan Hospital, Shanghai Medical College, Fudan University, Shanghai, China
| | - Nachuan Cheng
- Department of Neurology, Huashan Hospital, Fudan University, Shanghai, China; National Center for Neurological Disorders, Shanghai, China; Huashan Rare Disease Center, Huashan Hospital, Shanghai Medical College, Fudan University, Shanghai, China
| | - Jian Sun
- Department of Neurology, Huashan Hospital, Fudan University, Shanghai, China; National Center for Neurological Disorders, Shanghai, China; Huashan Rare Disease Center, Huashan Hospital, Shanghai Medical College, Fudan University, Shanghai, China
| | - Lan Chen
- Department of Neurology, Nantong First People's Hospital, Nantong, China
| | - Wanjin Chen
- Department of Neurology and Institute of Neurology of First Affiliated Hospital, Institute of Neuroscience, and Fujian Key Laboratory of Molecular Neurology, Fujian Medical University, Fuzhou, China
| | - Lingyun Gong
- Department of Neurology, Huashan Hospital, Fudan University, Shanghai, China; National Center for Neurological Disorders, Shanghai, China; Huashan Rare Disease Center, Huashan Hospital, Shanghai Medical College, Fudan University, Shanghai, China
| | - Kai Qiao
- Department of Neurology, Huashan Hospital, Fudan University, Shanghai, China; National Center for Neurological Disorders, Shanghai, China; Huashan Rare Disease Center, Huashan Hospital, Shanghai Medical College, Fudan University, Shanghai, China
| | - Jianying Xi
- Department of Neurology, Huashan Hospital, Fudan University, Shanghai, China; National Center for Neurological Disorders, Shanghai, China; Huashan Rare Disease Center, Huashan Hospital, Shanghai Medical College, Fudan University, Shanghai, China
| | - Qihan Wu
- Shanghai Ministry of Science and Technology Key Laboratory of Health and Disease Genomics, National Health Commission Key Lab of Reproduction Regulation, Shanghai Institute for Biomedical and Pharmaceutical Technologies, Shanghai, China
| | - Chongbo Zhao
- Department of Neurology, Huashan Hospital, Fudan University, Shanghai, China; National Center for Neurological Disorders, Shanghai, China; Huashan Rare Disease Center, Huashan Hospital, Shanghai Medical College, Fudan University, Shanghai, China
| | - Wenhua Zhu
- Department of Neurology, Huashan Hospital, Fudan University, Shanghai, China; National Center for Neurological Disorders, Shanghai, China; Huashan Rare Disease Center, Huashan Hospital, Shanghai Medical College, Fudan University, Shanghai, China.
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8
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Mahmoud M, Harting J, Corbitt H, Chen X, Jhangiani SN, Doddapaneni H, Meng Q, Han T, Lambert C, Zhang S, Baybayan P, Henno G, Shen H, Hu J, Han Y, Riegler C, Metcalf G, Henno G, Chinn IK, Eberle MA, Kingan S, Farinholt T, Carvalho CM, Gibbs RA, Kronenberg Z, Muzny D, Sedlazeck FJ. Closing the gap: Solving complex medically relevant genes at scale. MEDRXIV : THE PREPRINT SERVER FOR HEALTH SCIENCES 2024:2024.03.14.24304179. [PMID: 38562723 PMCID: PMC10984040 DOI: 10.1101/2024.03.14.24304179] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/04/2024]
Abstract
Comprehending the mechanism behind human diseases with an established heritable component represents the forefront of personalized medicine. Nevertheless, numerous medically important genes are inaccurately represented in short-read sequencing data analysis due to their complexity and repetitiveness or the so-called 'dark regions' of the human genome. The advent of PacBio as a long-read platform has provided new insights, yet HiFi whole-genome sequencing (WGS) cost remains frequently prohibitive. We introduce a targeted sequencing and analysis framework, Twist Alliance Dark Genes Panel (TADGP), designed to offer phased variants across 389 medically important yet complex autosomal genes. We highlight TADGP accuracy across eleven control samples and compare it to WGS. This demonstrates that TADGP achieves variant calling accuracy comparable to HiFi-WGS data, but at a fraction of the cost. Thus, enabling scalability and broad applicability for studying rare diseases or complementing previously sequenced samples to gain insights into these complex genes. TADGP revealed several candidate variants across all cases and provided insight into LPA diversity when tested on samples from rare disease and cardiovascular disease cohorts. In both cohorts, we identified novel variants affecting individual disease-associated genes (e.g., IKZF1, KCNE1). Nevertheless, the annotation of the variants across these 389 medically important genes remains challenging due to their underrepresentation in ClinVar and gnomAD. Consequently, we also offer an annotation resource to enhance the evaluation and prioritization of these variants. Overall, we can demonstrate that TADGP offers a cost-efficient and scalable approach to routinely assess the dark regions of the human genome with clinical relevance.
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Affiliation(s)
- Medhat Mahmoud
- Baylor College of Medicine, Human Genome Sequencing Center, Houston, Texas, USA
| | - John Harting
- Pacific Biosciences, Menlo Park, California, USA
| | | | - Xiao Chen
- Pacific Biosciences, Menlo Park, California, USA
| | | | - Harsha Doddapaneni
- Baylor College of Medicine, Human Genome Sequencing Center, Houston, Texas, USA
| | - Qingchang Meng
- Baylor College of Medicine, Human Genome Sequencing Center, Houston, Texas, USA
| | - Tina Han
- Twist Bioscience, South San Francisco, USA
| | | | - Siyuan Zhang
- Pacific Biosciences, Menlo Park, California, USA
| | | | - Geoff Henno
- Pacific Biosciences, Menlo Park, California, USA
| | - Hua Shen
- Baylor College of Medicine, Human Genome Sequencing Center, Houston, Texas, USA
| | - Jianhong Hu
- Baylor College of Medicine, Human Genome Sequencing Center, Houston, Texas, USA
| | - Yi Han
- Baylor College of Medicine, Human Genome Sequencing Center, Houston, Texas, USA
| | | | - Ginger Metcalf
- Baylor College of Medicine, Human Genome Sequencing Center, Houston, Texas, USA
| | - Geoff Henno
- Pacific Biosciences, Menlo Park, California, USA
| | - Ivan K. Chinn
- Department of Pediatrics, Section of Immunology Allergy and Rheumatology, Center for Human Immunobiology, Texas Children’s Hospital and Baylor College of Medicine, Houston, Texas, USA
| | | | - Sarah Kingan
- Pacific Biosciences, Menlo Park, California, USA
| | | | | | - Richard A. Gibbs
- Baylor College of Medicine, Human Genome Sequencing Center, Houston, Texas, USA
| | | | - Donna Muzny
- Baylor College of Medicine, Human Genome Sequencing Center, Houston, Texas, USA
| | - Fritz J. Sedlazeck
- Baylor College of Medicine, Human Genome Sequencing Center, Houston, Texas, USA
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, USA
- Department of Computer Science, Rice University, Houston, Texas, USA
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9
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Olivucci G, Iovino E, Innella G, Turchetti D, Pippucci T, Magini P. Long read sequencing on its way to the routine diagnostics of genetic diseases. Front Genet 2024; 15:1374860. [PMID: 38510277 PMCID: PMC10951082 DOI: 10.3389/fgene.2024.1374860] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2024] [Accepted: 02/26/2024] [Indexed: 03/22/2024] Open
Abstract
The clinical application of technological progress in the identification of DNA alterations has always led to improvements of diagnostic yields in genetic medicine. At chromosome side, from cytogenetic techniques evaluating number and gross structural defects to genomic microarrays detecting cryptic copy number variants, and at molecular level, from Sanger method studying the nucleotide sequence of single genes to the high-throughput next-generation sequencing (NGS) technologies, resolution and sensitivity progressively increased expanding considerably the range of detectable DNA anomalies and alongside of Mendelian disorders with known genetic causes. However, particular genomic regions (i.e., repetitive and GC-rich sequences) are inefficiently analyzed by standard genetic tests, still relying on laborious, time-consuming and low-sensitive approaches (i.e., southern-blot for repeat expansion or long-PCR for genes with highly homologous pseudogenes), accounting for at least part of the patients with undiagnosed genetic disorders. Third generation sequencing, generating long reads with improved mappability, is more suitable for the detection of structural alterations and defects in hardly accessible genomic regions. Although recently implemented and not yet clinically available, long read sequencing (LRS) technologies have already shown their potential in genetic medicine research that might greatly impact on diagnostic yield and reporting times, through their translation to clinical settings. The main investigated LRS application concerns the identification of structural variants and repeat expansions, probably because techniques for their detection have not evolved as rapidly as those dedicated to single nucleotide variants (SNV) identification: gold standard analyses are karyotyping and microarrays for balanced and unbalanced chromosome rearrangements, respectively, and southern blot and repeat-primed PCR for the amplification and sizing of expanded alleles, impaired by limited resolution and sensitivity that have not been significantly improved by the advent of NGS. Nevertheless, more recently, with the increased accuracy provided by the latest product releases, LRS has been tested also for SNV detection, especially in genes with highly homologous pseudogenes and for haplotype reconstruction to assess the parental origin of alleles with de novo pathogenic variants. We provide a review of relevant recent scientific papers exploring LRS potential in the diagnosis of genetic diseases and its potential future applications in routine genetic testing.
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Affiliation(s)
- Giulia Olivucci
- IRCCS Azienda Ospedaliero-Universitaria di Bologna, Bologna, Italy
- Department of Surgical and Oncological Sciences, University of Palermo, Palermo, Italy
| | - Emanuela Iovino
- IRCCS Azienda Ospedaliero-Universitaria di Bologna, Bologna, Italy
| | - Giovanni Innella
- Department of Medical and Surgical Sciences (DIMEC), University of Bologna, Bologna, Italy
- Medical Genetics Unit, IRCCS Azienda Ospedaliero-Universitaria di Bologna, Bologna, Italy
| | - Daniela Turchetti
- Department of Medical and Surgical Sciences (DIMEC), University of Bologna, Bologna, Italy
- Medical Genetics Unit, IRCCS Azienda Ospedaliero-Universitaria di Bologna, Bologna, Italy
| | - Tommaso Pippucci
- IRCCS Azienda Ospedaliero-Universitaria di Bologna, Bologna, Italy
| | - Pamela Magini
- Medical Genetics Unit, IRCCS Azienda Ospedaliero-Universitaria di Bologna, Bologna, Italy
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10
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Bai J, Qu Y, Huang W, Meng W, Zhan J, Wang H, Hou W, Jin Y, Mao A, Song F. A high-fidelity long-read sequencing-based approach enables accurate and effective genetic diagnosis of spinal muscular atrophy. Clin Chim Acta 2024; 553:117743. [PMID: 38158006 DOI: 10.1016/j.cca.2023.117743] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2023] [Revised: 12/08/2023] [Accepted: 12/21/2023] [Indexed: 01/03/2024]
Abstract
BACKGROUND We aimed to develop a high-fidelity long-read sequencing (LRS)-based approach to detect SMN gene variants in one step. It is challenging for conventional step-wise methods to simultaneously detect all kinds of variations between homologous SMN1 and SMN2. METHODS In this study, LRS was developed to analyze copy numbers (CNs), full sequences, and structure of SMN1 and SMN2. The results were compared with those from the step-wise methods in 202 samples from 67 families. RESULTS LRS achieved 100% (202/202) and 99.5% (201/202) accuracy for SMN1 and SMN2 CNs, respectively. It corrected SMN1 CNs from MLPA, which was caused by SNVs/indels that located in probe-binding region. LRS identified 23 SNVs/indels distributing throughout SMN1, including c.22dup and c.884A > T in trans-configuration, and a de novo variant c.41_42delinsC for the first time. LRS also identified a SMN2 variant c.346A > G. Moreover, it successfully determined Alu-mediated 8978-bp deletion encompassing exon 2a-5 and 1415-bp deletion disrupting exon 1, and the exact breakpoints of large deletions. Through haplotype-based pedigree trio analysis, LRS identified SMN1 2 + 0 carriers, and determined the distribution of SMN1 and SMN2 on two chromosomes. CONCLUSIONS LRS represents a more comprehensive and accurate diagnosis approach that is beneficial to early treatment and effective management of SMA.
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Affiliation(s)
- Jinli Bai
- Department of Medical Genetics, Capital Institute of Pediatrics, Beijing 100020, China
| | - Yujin Qu
- Department of Medical Genetics, Capital Institute of Pediatrics, Beijing 100020, China
| | - Wenchen Huang
- Department of Medical Genetics, Capital Institute of Pediatrics, Beijing 100020, China
| | - Wanli Meng
- Berry Genomics Corporation, Beijing 102200, China
| | - Jiahan Zhan
- Berry Genomics Corporation, Beijing 102200, China
| | - Hong Wang
- Department of Medical Genetics, Capital Institute of Pediatrics, Beijing 100020, China
| | - Wenqi Hou
- Berry Genomics Corporation, Beijing 102200, China
| | - Yuwei Jin
- Department of Medical Genetics, Capital Institute of Pediatrics, Beijing 100020, China
| | - Aiping Mao
- Berry Genomics Corporation, Beijing 102200, China.
| | - Fang Song
- Department of Medical Genetics, Capital Institute of Pediatrics, Beijing 100020, China.
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11
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Owusu R, Savarese M. Long-read sequencing improves diagnostic rate in neuromuscular disorders. ACTA MYOLOGICA : MYOPATHIES AND CARDIOMYOPATHIES : OFFICIAL JOURNAL OF THE MEDITERRANEAN SOCIETY OF MYOLOGY 2023; 42:123-128. [PMID: 38406378 PMCID: PMC10883326 DOI: 10.36185/2532-1900-394] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/30/2023] [Accepted: 12/05/2023] [Indexed: 02/27/2024]
Abstract
Massive parallel sequencing methods, such as exome, genome, and targeted DNA sequencing, have aided molecular diagnosis of genetic diseases in the last 20 years. However, short-read sequencing methods still have several limitations, such inaccurate genome assembly, the inability to detect large structural variants, and variants located in hard-to-sequence regions like highly repetitive areas. The recently emerged PacBio single-molecule real-time (SMRT) and Oxford nanopore technology (ONT) long-read sequencing (LRS) methods have been shown to overcome most of these technical issues, leading to an increase in diagnostic rate. LRS methods are contributing to the detection of repeat expansions in novel disease-causing genes (e.g., ABCD3, NOTCH2NLC and RILPL1 causing an Oculopharyngodistal myopathy or PLIN4 causing a Myopathy with rimmed ubiquitin-positive autophagic vacuolation), of structural variants (e.g., in DMD), and of single nucleotide variants in repetitive regions (TTN and NEB). Moreover, these methods have simplified the characterization of the D4Z4 repeats in DUX4, facilitating the diagnosis of Facioscapulohumeral muscular dystrophy (FSHD). We review recent studies that have used either ONT or PacBio SMRT sequencing methods and discuss different types of variants that have been detected using these approaches in individuals with neuromuscular disorders.
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Affiliation(s)
| | - Marco Savarese
- Folkhälsan Research Center, Helsinki, Finland
- University of Helsinki, Faculty of Medicine, Helsinki, Finland
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12
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Zhou Y, Jiang Y. Current Advances in Genetic Testing for Spinal Muscular Atrophy. Curr Genomics 2023; 24:273-286. [PMID: 38235355 PMCID: PMC10790334 DOI: 10.2174/0113892029273388231023072050] [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: 07/25/2023] [Revised: 09/22/2023] [Accepted: 10/02/2023] [Indexed: 01/19/2024] Open
Abstract
Spinal muscular atrophy (SMA) is one of the most common genetic disorders worldwide, and genetic testing plays a key role in its diagnosis and prevention. The last decade has seen a continuous flow of new methods for SMA genetic testing that, along with traditional approaches, have affected clinical practice patterns to some degree. Targeting different application scenarios and selecting the appropriate technique for genetic testing have become priorities for optimizing the clinical pathway for SMA. In this review, we summarize the latest technological innovations in genetic testing for SMA, including MassArray®, digital PCR (dPCR), next-generation sequencing (NGS), and third-generation sequencing (TGS). Implementation recommendations for rationally choosing different technical strategies in the tertiary prevention of SMA are also explored.
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Affiliation(s)
- Yulin Zhou
- United Diagnostic and Research Center for Clinical Genetics, Women and Children’s Hospital, School of Medicine & School of Public Health, Xiamen University, Xiamen, Fujian 361003, P.R. China
- Biobank, Women and Children’s Hospital, School of Medicine, Xiamen University, Xiamen, Fujian 361003, P.R. China
| | - Yu Jiang
- United Diagnostic and Research Center for Clinical Genetics, Women and Children’s Hospital, School of Medicine & School of Public Health, Xiamen University, Xiamen, Fujian 361003, P.R. China
- Biobank, Women and Children’s Hospital, School of Medicine, Xiamen University, Xiamen, Fujian 361003, P.R. China
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13
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Yu SY, Xi YL, Xu FQ, Zhang J, Liu YS. Application of long read sequencing in rare diseases: The longer, the better? Eur J Med Genet 2023; 66:104871. [PMID: 38832911 DOI: 10.1016/j.ejmg.2023.104871] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2023] [Revised: 10/11/2023] [Accepted: 10/22/2023] [Indexed: 06/06/2024]
Abstract
Rare diseases encompass a diverse group of genetic disorders that affect a small proportion of the population. Identifying the underlying genetic causes of these conditions presents significant challenges due to their genetic heterogeneity and complexity. Conventional short-read sequencing (SRS) techniques have been widely used in diagnosing and investigating of rare diseases, with limitations due to the nature of short-read lengths. In recent years, long read sequencing (LRS) technologies have emerged as a valuable tool in overcoming these limitations. This minireview provides a concise overview of the applications of LRS in rare disease research and diagnosis, including the identification of disease-causing tandem repeat expansions, structural variations, and comprehensive analysis of pathogenic variants with LRS.
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Affiliation(s)
- Si-Yan Yu
- Department of Pediatric Laboratory, Affiliated Children's Hospital of Jiangnan University (Wuxi Children's Hospital), Wuxi, Jiangsu, China; The First School of Clinical Medicine, Nanjing Medical University, Nanjing, Jiangsu, China
| | - Yu-Lin Xi
- Wuxi School of Medicine, Jiangnan University, Wuxi, Jiangsu, China
| | - Fu-Qiang Xu
- Department of Gynecology, Beijing Youan Hospital, Capital Medical University, Beijing, China
| | - Jian Zhang
- Department of Medical Laboratory, Affiliated Children's Hospital of Jiangnan University (Wuxi Children's Hospital), Wuxi, Jiangsu, China.
| | - Yan-Shan Liu
- Department of Pediatric Laboratory, Affiliated Children's Hospital of Jiangnan University (Wuxi Children's Hospital), Wuxi, Jiangsu, China; Wuxi School of Medicine, Jiangnan University, Wuxi, Jiangsu, China.
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14
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Li S, Han X, Zhang L, Xu Y, Chang C, Gao L, Zhan J, Hua R, Mao A, Wang Y. An Effective and Universal Long-Read Sequencing-Based Approach for SMN1 2 + 0 Carrier Screening through Family Trio Analysis. Clin Chem 2023; 69:1295-1306. [PMID: 37932106 DOI: 10.1093/clinchem/hvad152] [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: 07/05/2023] [Accepted: 08/28/2023] [Indexed: 11/08/2023]
Abstract
BACKGROUND Population-wide carrier screening for spinal muscular atrophy (SMA) is recommended by professional organizations to facilitate informed reproductive options. However, genetic screening for SMN1 2 + 0 carriers, accounting for 3%-8% of all SMA carriers, has been challenging due to the large gene size and long distance between the 2 SMN genes. METHODS Here we repurposed a previously developed long-read sequencing-based approach, termed comprehensive analysis of SMA (CASMA), to identify SMN1 2 + 0 carriers through haplotype analysis in family trios (CASMA-trio). Bioinformatics pipelines were developed for accurate haplotype analysis and SMN1 2 + 0 deduction. Seventy-nine subjects from 24 families composed of, at the minimum, 3 were enrolled, and CASMA-trio was employed to determine whether an index subject with 2 SMN1 copies was a 2 + 0 carrier in these families. For the proof-of-principle, SMN2 2 + 0 was also analyzed. RESULTS Among the 16 subjects with 2 SMN1 copies, CASMA-trio identified 5 subjects from 4 families as SMN1 2 + 0 carriers, which was consistent with pedigree analysis involving an affected proband. CASMA-trio also identified SMN2 2 + 0 in six out of 43 subjects with 2 SMN2 copies. Additionally, CASMA-trio successfully determined the distribution pattern of SMN1 and SMN2 genes on 2 alleles in all 79 subjects. CONCLUSIONS CASMA-trio represents an effective and universal approach for SMN1 2 + 0 carriers screening, as it does not reply on the presence of an affected proband, certain single-nucleotide polymorphisms, ethnicity-specific haplotypes, or complicated single-nucleotide polymorphism analysis across 3 generations. Incorporating CASMA-trio into existing SMA carrier screening programs will greatly reduce residual risk ratio.
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Affiliation(s)
- Shuyuan Li
- International Peace Maternity and Child Health Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai 200030, China
- Shanghai Key Laboratory of Embryo Original Diseases, Shanghai 200030, China
- Institute of Birth Defects and Rare Diseases, School of Medicine, Shanghai Jiao Tong University, Shanghai 200030, China
| | - Xu Han
- International Peace Maternity and Child Health Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai 200030, China
- Shanghai Key Laboratory of Embryo Original Diseases, Shanghai 200030, China
- Institute of Birth Defects and Rare Diseases, School of Medicine, Shanghai Jiao Tong University, Shanghai 200030, China
| | - Liang Zhang
- International Peace Maternity and Child Health Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai 200030, China
- Shanghai Key Laboratory of Embryo Original Diseases, Shanghai 200030, China
- Institute of Birth Defects and Rare Diseases, School of Medicine, Shanghai Jiao Tong University, Shanghai 200030, China
| | - Yan Xu
- International Peace Maternity and Child Health Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai 200030, China
- Shanghai Key Laboratory of Embryo Original Diseases, Shanghai 200030, China
- Institute of Birth Defects and Rare Diseases, School of Medicine, Shanghai Jiao Tong University, Shanghai 200030, China
| | - Chunxin Chang
- International Peace Maternity and Child Health Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai 200030, China
- Shanghai Key Laboratory of Embryo Original Diseases, Shanghai 200030, China
- Institute of Birth Defects and Rare Diseases, School of Medicine, Shanghai Jiao Tong University, Shanghai 200030, China
| | - Li Gao
- International Peace Maternity and Child Health Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai 200030, China
- Shanghai Key Laboratory of Embryo Original Diseases, Shanghai 200030, China
- Institute of Birth Defects and Rare Diseases, School of Medicine, Shanghai Jiao Tong University, Shanghai 200030, China
| | - Jiahan Zhan
- Berry Genomics Corporation, Beijing 102200, China
| | - Renyi Hua
- International Peace Maternity and Child Health Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai 200030, China
- Shanghai Key Laboratory of Embryo Original Diseases, Shanghai 200030, China
- Institute of Birth Defects and Rare Diseases, School of Medicine, Shanghai Jiao Tong University, Shanghai 200030, China
| | - Aiping Mao
- Berry Genomics Corporation, Beijing 102200, China
| | - Yanlin Wang
- International Peace Maternity and Child Health Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai 200030, China
- Shanghai Key Laboratory of Embryo Original Diseases, Shanghai 200030, China
- Institute of Birth Defects and Rare Diseases, School of Medicine, Shanghai Jiao Tong University, Shanghai 200030, China
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15
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Ling X, Wang C, Li L, Pan L, Huang C, Zhang C, Huang Y, Qiu Y, Lin F, Huang Y. Third-generation sequencing for genetic disease. Clin Chim Acta 2023; 551:117624. [PMID: 37923104 DOI: 10.1016/j.cca.2023.117624] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2023] [Revised: 10/31/2023] [Accepted: 10/31/2023] [Indexed: 11/07/2023]
Abstract
Third-generation sequencing (TGS) has led to a brave new revolution in detecting genetic diseases over the last few years. TGS has been rapidly developed for genetic disease applications owing to its significant advantages such as long read length, rapid detection, and precise detection of complex and rare structural variants. This approach greatly improves the efficiency of disease diagnosis and complements the shortcomings of short-read sequencing. In this paper, we first briefly introduce the working mechanism of one of the most important representatives of TGS, single-molecule real-time (SMRT) sequencing by Pacific Bioscience (PacBio), followed by a review and comparison of the advantages and disadvantages of different sequencing technologies. Finally, we focused on the progress of SMRT sequencing applications in genetic disease detection. Future perspectives on the applications of TGS in other fields were also presented. With the continuous innovation of the SMRT technologies and the expansion of their fields of application, SMRT sequencing has broad clinical application prospects in genetic diseases detection, and is expected to become an important tool for the molecular diagnosis of other diseases.
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Affiliation(s)
- Xiaoting Ling
- Department of Clinical Laboratory, The First Affiliated Hospital of Guangxi Medical University, Key Laboratory of Clinical Laboratory Medicine of Guangxi Department of Education, Guangxi Medical University, Nanning 530021, China
| | - Chenghan Wang
- Department of Clinical Laboratory, The First Affiliated Hospital of Guangxi Medical University, Key Laboratory of Clinical Laboratory Medicine of Guangxi Department of Education, Guangxi Medical University, Nanning 530021, China
| | - Linlin Li
- Department of Clinical Laboratory, The First Affiliated Hospital of Guangxi Medical University, Key Laboratory of Clinical Laboratory Medicine of Guangxi Department of Education, Guangxi Medical University, Nanning 530021, China
| | - Liqiu Pan
- Department of Clinical Laboratory, The First Affiliated Hospital of Guangxi Medical University, Key Laboratory of Clinical Laboratory Medicine of Guangxi Department of Education, Guangxi Medical University, Nanning 530021, China
| | - Chaoyu Huang
- Department of Clinical Laboratory, The First Affiliated Hospital of Guangxi Medical University, Key Laboratory of Clinical Laboratory Medicine of Guangxi Department of Education, Guangxi Medical University, Nanning 530021, China
| | - Caixia Zhang
- Department of Clinical Laboratory, The First Affiliated Hospital of Guangxi Medical University, Key Laboratory of Clinical Laboratory Medicine of Guangxi Department of Education, Guangxi Medical University, Nanning 530021, China
| | - Yunhua Huang
- Department of Clinical Laboratory, The First Affiliated Hospital of Guangxi Medical University, Key Laboratory of Clinical Laboratory Medicine of Guangxi Department of Education, Guangxi Medical University, Nanning 530021, China
| | - Yuling Qiu
- NHC Key Laboratory of Thalassemia Medicine, Guangxi Medical University, Nanning 530021, China; Guangxi Key Laboratory of Thalassemia Research, Guangxi Medical University, Nanning 530021, China
| | - Faquan Lin
- Department of Clinical Laboratory, The First Affiliated Hospital of Guangxi Medical University, Key Laboratory of Clinical Laboratory Medicine of Guangxi Department of Education, Guangxi Medical University, Nanning 530021, China.
| | - Yifang Huang
- Department of Clinical Laboratory, The First Affiliated Hospital of Guangxi Medical University, Key Laboratory of Clinical Laboratory Medicine of Guangxi Department of Education, Guangxi Medical University, Nanning 530021, China.
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16
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Shalata A, Bar-Shai M, Hadid Y, Mahroum M, Mintz H, Shalata ZE, Radzishevsky E, Genizi J, Lorber A, Ben-Yosef T, Yaniv L. Danon Disease: Entire LAMP2 Gene Deletion with Unusual Clinical Presentation-Case Report and Review of the Literature. Genes (Basel) 2023; 14:1539. [PMID: 37628591 PMCID: PMC10454823 DOI: 10.3390/genes14081539] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2023] [Revised: 07/17/2023] [Accepted: 07/25/2023] [Indexed: 08/27/2023] Open
Abstract
Danon disease is a rare x-linked dominant multisystemic disorder with a clinical triad of severe cardiomyopathy, skeletal myopathy, and intellectual disability. It is caused by defects in the lysosome-associated membrane protein-2 (LAMP2) gene. Numerous different mutations in the LAMP2 protein have been described. Danon disease is typically lethal by the mid-twenties in male patients due to cardiomyopathy and heart failure. Female patients usually present with milder and variable symptoms. This report describes a 42-year-old father and his 3-year-old daughter presenting with mild manifestations of the disease. The father has normal intellectual development and normal physical activity. At the age of 13, he was diagnosed with mild ventricular pre-excitation known as Wolf-Parkinson-White syndrome (WPWs), very mild and mostly asymptomatic cardiomyopathy and left ventricular hypertrophy, and at about the age of 25 presented with visual impairment due to cone-rod dystrophy. His daughter showed normal development and very mild asymptomatic electrocardiographic WPWs abnormalities with left mild ventricular hypertrophy. Genetic testing revealed an Xq24 microdeletion encompassing the entire LAMP2 gene. Relevant literature was reviewed as a reference for the etiology, diagnosis, treatment and case management.
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Affiliation(s)
- Adel Shalata
- The Simon Winter Institute for Human Genetics, Bnai Zion Medical Center, Haifa 32000, Israel; (Y.H.); (M.M.); (H.M.)
- Ruth and Bruce Rappaport Faculty of Medicine, Technion-Israel Institute of Technology, Haifa 32000, Israel; (E.R.); (J.G.); (A.L.); (T.B.-Y.); (L.Y.)
| | - Marina Bar-Shai
- The Institute of Medical Genetics, Carmel Medical Center, Haifa 34362, Israel;
| | - Yarin Hadid
- The Simon Winter Institute for Human Genetics, Bnai Zion Medical Center, Haifa 32000, Israel; (Y.H.); (M.M.); (H.M.)
| | - Muhammad Mahroum
- The Simon Winter Institute for Human Genetics, Bnai Zion Medical Center, Haifa 32000, Israel; (Y.H.); (M.M.); (H.M.)
| | - Hila Mintz
- The Simon Winter Institute for Human Genetics, Bnai Zion Medical Center, Haifa 32000, Israel; (Y.H.); (M.M.); (H.M.)
| | | | - Evgeny Radzishevsky
- Ruth and Bruce Rappaport Faculty of Medicine, Technion-Israel Institute of Technology, Haifa 32000, Israel; (E.R.); (J.G.); (A.L.); (T.B.-Y.); (L.Y.)
- Cardiology Department, Bnai Zion Medical Center, Haifa 32000, Israel
| | - Jacob Genizi
- Ruth and Bruce Rappaport Faculty of Medicine, Technion-Israel Institute of Technology, Haifa 32000, Israel; (E.R.); (J.G.); (A.L.); (T.B.-Y.); (L.Y.)
- Department of Pediatric, Bnai Zion Medical Center, Haifa 32000, Israel
| | - Avraham Lorber
- Ruth and Bruce Rappaport Faculty of Medicine, Technion-Israel Institute of Technology, Haifa 32000, Israel; (E.R.); (J.G.); (A.L.); (T.B.-Y.); (L.Y.)
- Pediatric Cardiology Unit, Rambam Medical Centre, Haifa 31096, Israel
| | - Tamar Ben-Yosef
- Ruth and Bruce Rappaport Faculty of Medicine, Technion-Israel Institute of Technology, Haifa 32000, Israel; (E.R.); (J.G.); (A.L.); (T.B.-Y.); (L.Y.)
| | - Liat Yaniv
- Ruth and Bruce Rappaport Faculty of Medicine, Technion-Israel Institute of Technology, Haifa 32000, Israel; (E.R.); (J.G.); (A.L.); (T.B.-Y.); (L.Y.)
- Department of Pediatric, Bnai Zion Medical Center, Haifa 32000, Israel
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17
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Zeng W, Kong X, Alamana C, Liu Y, Guzman J, Pang PD, Day JW, Wu JC. Generation of two induced pluripotent stem cell lines from spinal muscular atrophy type 1 patients carrying no functional copies of SMN1 gene. Stem Cell Res 2023; 69:103095. [PMID: 37087898 PMCID: PMC11068589 DOI: 10.1016/j.scr.2023.103095] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/06/2023] [Revised: 04/10/2023] [Accepted: 04/12/2023] [Indexed: 04/25/2023] Open
Abstract
Spinal muscular atrophy (SMA) is a severe neurodegenerative muscular disease caused by the homozygous loss of survival of motor neuron 1 (SMN1) genes. SMA patients exhibit marked skeletal muscle (SKM) loss, eventually leading to death. Here we generated two iPSC lines from two SMA type I patients with homozygous SMN1 mutations and validated the pluripotency and the ability to differentiate into three germ layers. The iPSC lines can be applied to generate skeletal muscles to model muscle atrophy of SMA that persists after treatment of motor neurons and will serve as a complementary platform for drug screening in vitro.
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Affiliation(s)
- Wenshu Zeng
- Stanford Cardiovascular Institute, Stanford University, Stanford, CA 94305, USA; Department of Medicine, Division of Cardiology, Stanford University, Stanford, CA 94305, USA
| | - Xiaohui Kong
- Stanford Cardiovascular Institute, Stanford University, Stanford, CA 94305, USA; Department of Medicine, Division of Cardiology, Stanford University, Stanford, CA 94305, USA
| | - Christina Alamana
- Stanford Cardiovascular Institute, Stanford University, Stanford, CA 94305, USA; Department of Medicine, Division of Cardiology, Stanford University, Stanford, CA 94305, USA
| | - Yu Liu
- Stanford Cardiovascular Institute, Stanford University, Stanford, CA 94305, USA; Department of Medicine, Division of Cardiology, Stanford University, Stanford, CA 94305, USA
| | - Jessica Guzman
- Department of Neurology, Stanford University, Stanford, CA 94305, USA
| | - Paul D Pang
- Greenstone Biosciences, Palo Alto, CA 94304, USA
| | - John W Day
- Department of Neurology, Stanford University, Stanford, CA 94305, USA
| | - Joseph C Wu
- Stanford Cardiovascular Institute, Stanford University, Stanford, CA 94305, USA; Department of Medicine, Division of Cardiology, Stanford University, Stanford, CA 94305, USA; Greenstone Biosciences, Palo Alto, CA 94304, USA.
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18
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Kleinle S, Scholz V, Benet-Pagés A, Wohlfrom T, Gehling S, Scharf F, Rost S, Prott EC, Grinzinger S, Hotter A, Haug V, Niemeier S, Wiethoff-Ubrig L, Hagenacker T, Goldhahn K, von Moers A, Walter MC, Reilich P, Eggermann K, Kraft F, Kurth I, Erdmann H, Holinski-Feder E, Neuhann T, Abicht A. Closing the Gap - Detection of 5q-Spinal Muscular Atrophy by Short-Read Next-Generation Sequencing and Unexpected Results in a Diagnostic Patient Cohort. J Neuromuscul Dis 2023; 10:835-846. [PMID: 37424474 PMCID: PMC10578226 DOI: 10.3233/jnd-221668] [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] [Accepted: 06/20/2023] [Indexed: 07/11/2023]
Abstract
BACKGROUND The importance of early diagnosis of 5q-Spinal muscular atrophy (5q-SMA) has heightened as early intervention can significantly improve clinical outcomes. In 96% of cases, 5q-SMA is caused by a homozygous deletion of SMN1. Around 4 % of patients carry a SMN1 deletion and a single-nucleotide variant (SNV) on the other allele. Traditionally, diagnosis is based on multiplex ligation probe amplification (MLPA) to detect homozygous or heterozygous exon 7 deletions in SMN1. Due to high homologies within the SMN1/SMN2 locus, sequence analysis to identify SNVs of the SMN1 gene is unreliable by standard Sanger or short-read next-generation sequencing (srNGS) methods. OBJECTIVE The objective was to overcome the limitations in high-throughput srNGS with the aim of providing SMA patients with a fast and reliable diagnosis to enable their timely therapy. METHODS A bioinformatics workflow to detect homozygous SMN1 deletions and SMN1 SNVs on srNGS analysis was applied to diagnostic whole exome and panel testing for suggested neuromuscular disorders (1684 patients) and to fetal samples in prenatal diagnostics (260 patients). SNVs were detected by aligning sequencing reads from SMN1 and SMN2 to an SMN1 reference sequence. Homozygous SMN1 deletions were identified by filtering sequence reads for the ,, gene-determining variant" (GDV). RESULTS 10 patients were diagnosed with 5q-SMA based on (i) SMN1 deletion and hemizygous SNV (2 patients), (ii) homozygous SMN1 deletion (6 patients), and (iii) compound heterozygous SNVs in SMN1 (2 patients). CONCLUSIONS Applying our workflow in srNGS-based panel and whole exome sequencing (WES) is crucial in a clinical laboratory, as otherwise patients with an atypical clinical presentation initially not suspected to suffer from SMA remain undiagnosed.
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Affiliation(s)
| | | | - Anna Benet-Pagés
- Medical Genetics Center, Munich, Germany
- Institute of Neurogenomics, Helmholtz Center Munich, Neuherberg, Germany
| | | | | | | | | | | | - Susanne Grinzinger
- Christian Doppler Clinic, Neurology, University Hospital Salzburg, Salzburg, Austria
| | - Anna Hotter
- Department of Neurology, Medical University of Innsbruck, Innsbruck, Austria
| | - Verena Haug
- Neuropediatrics, University Medical Center Mainz, Mainz, Germany
| | | | - Lucia Wiethoff-Ubrig
- Children’s and Adolescents’ Hospital Datteln, Neuropediatrics, Witten/Herdecke University, Datteln, Germany
| | - Tim Hagenacker
- Department of Neurology and Center for Translational Neuro- and Behavioral Sciences (C-TNBS), University Hospital Essen, Essen, Germany
| | - Klaus Goldhahn
- Department of Pediatrics and Neuropediatrics, DRK Clinics Berlin, Berlin, Germany
| | - Arpad von Moers
- Department of Pediatrics and Neuropediatrics, DRK Clinics Berlin, Berlin, Germany
| | - Maggie C. Walter
- Friedrich Baur Institute at the Department of Neurology, University Hospital, LMU Munich, Munich, Germany
| | - Peter Reilich
- Friedrich Baur Institute at the Department of Neurology, University Hospital, LMU Munich, Munich, Germany
| | - Katja Eggermann
- Institute for Human Genetics and Genomic Medicine, Medical Faculty, RWTH Aachen University, Aachen, Germany
| | - Florian Kraft
- Institute for Human Genetics and Genomic Medicine, Medical Faculty, RWTH Aachen University, Aachen, Germany
| | - Ingo Kurth
- Institute for Human Genetics and Genomic Medicine, Medical Faculty, RWTH Aachen University, Aachen, Germany
| | - Hannes Erdmann
- Medical Genetics Center, Munich, Germany
- Friedrich Baur Institute at the Department of Neurology, University Hospital, LMU Munich, Munich, Germany
| | - Elke Holinski-Feder
- Medical Genetics Center, Munich, Germany
- Department of Medicine IV, University Hospital, LMU Munich, Munich, Germany
| | | | - Angela Abicht
- Medical Genetics Center, Munich, Germany
- Friedrich Baur Institute at the Department of Neurology, University Hospital, LMU Munich, Munich, Germany
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