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Yang L, Huo Y, Wang M, Zhang D, Zhang T, Wu H, Rao X, Meng H, Yin S, Mei J, Zhang D, Chen X, Lv J, Liu M, Cheng Y, Guan Y, Feng B, Song G, Yi C, Liu M, Zeng F, Wang L, Li D. Engineering APOBEC3A deaminase for highly accurate and efficient base editing. Nat Chem Biol 2024; 20:1176-1187. [PMID: 38553609 DOI: 10.1038/s41589-024-01595-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2023] [Accepted: 02/29/2024] [Indexed: 08/30/2024]
Abstract
Cytosine base editors (CBEs) are effective tools for introducing C-to-T base conversions, but their clinical applications are limited by off-target and bystander effects. Through structure-guided engineering of human APOBEC3A (A3A) deaminase, we developed highly accurate A3A-CBE (haA3A-CBE) variants that efficiently generate C-to-T conversion with a narrow editing window and near-background level of DNA and RNA off-target activity, irrespective of methylation status and sequence context. The engineered deaminase domains are compatible with PAM-relaxed SpCas9-NG variant, enabling accurate correction of pathogenic mutations in homopolymeric cytosine sites through flexible positioning of the single-guide RNAs. Dual adeno-associated virus delivery of one haA3A-CBE variant to a mouse model of tyrosinemia induced up to 58.1% editing in liver tissues with minimal bystander editing, which was further reduced through single dose of lipid nanoparticle-based messenger RNA delivery of haA3A-CBEs. These results highlight the tremendous promise of haA3A-CBEs for precise genome editing to treat human diseases.
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Affiliation(s)
- Lei Yang
- Shanghai Frontiers Science Center of Genome Editing and Cell Therapy, Shanghai Key Laboratory of Regulatory Biology, Institute of Biomedical Sciences and School of Life Sciences, East China Normal University, Shanghai, China
| | - Yanan Huo
- Shanghai Frontiers Science Center of Genome Editing and Cell Therapy, Shanghai Key Laboratory of Regulatory Biology, Institute of Biomedical Sciences and School of Life Sciences, East China Normal University, Shanghai, China
| | - Man Wang
- Shanghai Frontiers Science Center of Genome Editing and Cell Therapy, Shanghai Key Laboratory of Regulatory Biology, Institute of Biomedical Sciences and School of Life Sciences, East China Normal University, Shanghai, China
| | - Dan Zhang
- Shanghai Frontiers Science Center of Genome Editing and Cell Therapy, Shanghai Key Laboratory of Regulatory Biology, Institute of Biomedical Sciences and School of Life Sciences, East China Normal University, Shanghai, China
| | - Tianai Zhang
- Shanghai Frontiers Science Center of Genome Editing and Cell Therapy, Shanghai Key Laboratory of Regulatory Biology, Institute of Biomedical Sciences and School of Life Sciences, East China Normal University, Shanghai, China
| | - Hao Wu
- Peking-Tsinghua Center for Life Sciences, Peking University, Beijing, China
| | - Xichen Rao
- Peking-Tsinghua Center for Life Sciences, Peking University, Beijing, China
| | - Haowei Meng
- Peking-Tsinghua Center for Life Sciences, Peking University, Beijing, China
| | - Shuming Yin
- Shanghai Frontiers Science Center of Genome Editing and Cell Therapy, Shanghai Key Laboratory of Regulatory Biology, Institute of Biomedical Sciences and School of Life Sciences, East China Normal University, Shanghai, China
| | - Jiale Mei
- Shanghai Frontiers Science Center of Genome Editing and Cell Therapy, Shanghai Key Laboratory of Regulatory Biology, Institute of Biomedical Sciences and School of Life Sciences, East China Normal University, Shanghai, China
| | - Dexin Zhang
- Xinhua Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Xi Chen
- BRL Medicine Inc., Shanghai, China
| | - Jia Lv
- Shanghai Frontiers Science Center of Genome Editing and Cell Therapy, Shanghai Key Laboratory of Regulatory Biology, Institute of Biomedical Sciences and School of Life Sciences, East China Normal University, Shanghai, China
| | - Meizhen Liu
- Shanghai Frontiers Science Center of Genome Editing and Cell Therapy, Shanghai Key Laboratory of Regulatory Biology, Institute of Biomedical Sciences and School of Life Sciences, East China Normal University, Shanghai, China
| | - Yiyun Cheng
- Shanghai Frontiers Science Center of Genome Editing and Cell Therapy, Shanghai Key Laboratory of Regulatory Biology, Institute of Biomedical Sciences and School of Life Sciences, East China Normal University, Shanghai, China
| | - Yuting Guan
- Shanghai Frontiers Science Center of Genome Editing and Cell Therapy, Shanghai Key Laboratory of Regulatory Biology, Institute of Biomedical Sciences and School of Life Sciences, East China Normal University, Shanghai, China
| | - Bo Feng
- School of Biomedical Sciences, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong SAR, China
| | - Gaojie Song
- Shanghai Frontiers Science Center of Genome Editing and Cell Therapy, Shanghai Key Laboratory of Regulatory Biology, Institute of Biomedical Sciences and School of Life Sciences, East China Normal University, Shanghai, China
| | - Chengqi Yi
- Peking-Tsinghua Center for Life Sciences, Peking University, Beijing, China
| | - Mingyao Liu
- Shanghai Frontiers Science Center of Genome Editing and Cell Therapy, Shanghai Key Laboratory of Regulatory Biology, Institute of Biomedical Sciences and School of Life Sciences, East China Normal University, Shanghai, China
- BRL Medicine Inc., Shanghai, China
| | - Fanyi Zeng
- Department of Histo-Embryology, Genetics and Developmental Biology, Shanghai Jiao Tong University School of Medicine, Shanghai, China.
| | - Liren Wang
- Shanghai Frontiers Science Center of Genome Editing and Cell Therapy, Shanghai Key Laboratory of Regulatory Biology, Institute of Biomedical Sciences and School of Life Sciences, East China Normal University, Shanghai, China.
| | - Dali Li
- Shanghai Frontiers Science Center of Genome Editing and Cell Therapy, Shanghai Key Laboratory of Regulatory Biology, Institute of Biomedical Sciences and School of Life Sciences, East China Normal University, Shanghai, China.
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Alpaslan M, Fastré E, Mestre S, van Haeringen A, Repetto GM, Keymolen K, Boon LM, Belva F, Giacalone G, Revencu N, Sznajer Y, Riches K, Keeley V, Mansour S, Gordon K, Martin-Almedina S, Dobbins S, Ostergaard P, Quere I, Brouillard P, Vikkula M. Pathogenic variants in HGF give rise to childhood-to-late onset primary lymphoedema by loss of function. Hum Mol Genet 2024; 33:1250-1261. [PMID: 38676400 PMCID: PMC11227619 DOI: 10.1093/hmg/ddae060] [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: 10/28/2023] [Revised: 03/01/2024] [Accepted: 03/19/2024] [Indexed: 04/28/2024] Open
Abstract
Developmental and functional defects in the lymphatic system are responsible for primary lymphoedema (PL). PL is a chronic debilitating disease caused by increased accumulation of interstitial fluid, predisposing to inflammation, infections and fibrosis. There is no cure, only symptomatic treatment is available. Thirty-two genes or loci have been linked to PL, and another 22 are suggested, including Hepatocyte Growth Factor (HGF). We searched for HGF variants in 770 index patients from the Brussels PL cohort. We identified ten variants predicted to cause HGF loss-of-function (six nonsense, two frameshifts, and two splice-site changes; 1.3% of our cohort), and 14 missense variants predicted to be pathogenic in 17 families (2.21%). We studied co-segregation within families, mRNA stability for non-sense variants, and in vitro functional effects of the missense variants. Analyses of the mRNA of patient cells revealed degradation of the nonsense mutant allele. Reduced protein secretion was detected for nine of the 14 missense variants expressed in COS-7 cells. Stimulation of lymphatic endothelial cells with these 14 HGF variant proteins resulted in decreased activation of the downstream targets AKT and ERK1/2 for three of them. Clinically, HGF-associated PL was diverse, but predominantly bilateral in the lower limbs with onset varying from early childhood to adulthood. Finally, aggregation study in a second independent cohort underscored that rare likely pathogenic variants in HGF explain about 2% of PL. Therefore, HGF signalling seems crucial for lymphatic development and/or maintenance in human beings and HGF should be included in diagnostic genetic screens for PL.
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Affiliation(s)
- Murat Alpaslan
- Human Molecular Genetics, de Duve Institute, University of Louvain, Avenue Hippocrate 74, Brussels 1200, Belgium
| | - Elodie Fastré
- Human Molecular Genetics, de Duve Institute, University of Louvain, Avenue Hippocrate 74, Brussels 1200, Belgium
| | - Sandrine Mestre
- Department of vascular medicine, Hospital Saint-Eloi, University Hospital of Montpellier, Avenue Augustin Fliche 80, Montpellier 34090, France
| | - Arie van Haeringen
- Leiden University Medical Center, Albinusdreef 2, Leiden 2333, the Netherlands
| | - Gabriela M Repetto
- Clinica Alemana Universidad del Desarrollo, Av Plaza 680, Las Condes, Lo Barnechea, Región Metropolitana 7710167, Chile
| | - Kathelijn Keymolen
- Clinical Sciences, Research Group Reproduction and Genetics, Centre for Medical Genetics, Vrije Universiteit Brussel (VUB), Universitair Ziekenhuis Brussel (UZ Brussel), Laarbeeklaan 101, Brussels 1090, Belgium
| | - Laurence M Boon
- Center for Vascular Anomalies, Division of Plastic Surgery, Cliniques Universitaires Saint-Luc, University of Louvain, Avenue Hippocrate 10, Brussels 1200, Belgium
| | - Florence Belva
- Department of Lymphatic Surgery, AZ Sint-Maarten Hospital, VASCERN PPL European Reference Centre, Liersesteenweg 435, Mechelen 2800, Belgium
| | - Guido Giacalone
- Department of Lymphatic Surgery, AZ Sint-Maarten Hospital, VASCERN PPL European Reference Centre, Liersesteenweg 435, Mechelen 2800, Belgium
| | - Nicole Revencu
- Center for Human Genetics, Cliniques Universitaires Saint-Luc, University of Louvain, Avenue Hippocrate 10, Brussels 1200, Belgium
| | - Yves Sznajer
- Center for Human Genetics, Cliniques Universitaires Saint-Luc, University of Louvain, Avenue Hippocrate 10, Brussels 1200, Belgium
| | - Katie Riches
- University Hospitals of Derby and Burton NHS Foundation Trust, Uttoxeter Rd, Derby DE22 3NE, United Kingdom
| | - Vaughan Keeley
- University Hospitals of Derby and Burton NHS Foundation Trust, Uttoxeter Rd, Derby DE22 3NE, United Kingdom
- University of Nottingham Medical School, Nottingham, East Block, Lenton, Nottingham NG7 2UH, United Kingdom
| | - Sahar Mansour
- Cardiovascular and Genomics Research Institute, St. George's University of London, Blackshaw Rd, London SW17 0QT, United Kingdom
- South West Thames Regional Centre for Genomics, St. George's Universities Hospitals NHS Foundation Trust, Blackshaw Rd, London SW17 0QT, United Kingdom
| | - Kristiana Gordon
- Cardiovascular and Genomics Research Institute, St. George's University of London, Blackshaw Rd, London SW17 0QT, United Kingdom
- Dermatology and Lymphovascular Medicine, St. George's Universities NHS Foundation Trust, Blackshaw Rd, London SW17 0QT, United Kingdom
| | - Silvia Martin-Almedina
- Cardiovascular and Genomics Research Institute, St. George's University of London, Blackshaw Rd, London SW17 0QT, United Kingdom
| | - Sara Dobbins
- Cardiovascular and Genomics Research Institute, St. George's University of London, Blackshaw Rd, London SW17 0QT, United Kingdom
| | - Pia Ostergaard
- Cardiovascular and Genomics Research Institute, St. George's University of London, Blackshaw Rd, London SW17 0QT, United Kingdom
| | - Isabelle Quere
- Department of vascular medicine, Hospital Saint-Eloi, University Hospital of Montpellier, Avenue Augustin Fliche 80, Montpellier 34090, France
| | - Pascal Brouillard
- Human Molecular Genetics, de Duve Institute, University of Louvain, Avenue Hippocrate 74, Brussels 1200, Belgium
| | - Miikka Vikkula
- Human Molecular Genetics, de Duve Institute, University of Louvain, Avenue Hippocrate 74, Brussels 1200, Belgium
- WELBIO Department, WEL Research Institute, Avenue Pasteur, 6, Wavre 1300, Belgium
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3
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Tlili A, Mahfood M, Al Mutery A, Chouchen J. Genetic analysis of 106 sporadic cases with hearing loss in the UAE population. Hum Genomics 2024; 18:59. [PMID: 38844983 PMCID: PMC11157727 DOI: 10.1186/s40246-024-00630-8] [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: 02/03/2024] [Accepted: 05/27/2024] [Indexed: 06/09/2024] Open
Abstract
BACKGROUND Hereditary hearing loss is a rare hereditary condition that has a significant presence in consanguineous populations. Despite its prevalence, hearing loss is marked by substantial genetic diversity, which poses challenges for diagnosis and screening, particularly in cases with no clear family history or when the impact of the genetic variant requires functional analysis, such as in the case of missense mutations and UTR variants. The advent of next-generation sequencing (NGS) has transformed the identification of genes and variants linked to various conditions, including hearing loss. However, there remains a high proportion of undiagnosed patients, attributable to various factors, including limitations in sequencing coverage and gaps in our knowledge of the entire genome, among other factors. In this study, our objective was to comprehensively identify the spectrum of genes and variants associated with hearing loss in a cohort of 106 affected individuals from the UAE. RESULTS In this study, we investigated 106 sporadic cases of hearing impairment and performed genetic analyses to identify causative mutations. Screening of the GJB2 gene in these cases revealed its involvement in 24 affected individuals, with specific mutations identified. For individuals without GJB2 mutations, whole exome sequencing (WES) was conducted. WES revealed 33 genetic variants, including 6 homozygous and 27 heterozygous DNA changes, two of which were previously implicated in hearing loss, while 25 variants were novel. We also observed multiple potential pathogenic heterozygous variants across different genes in some cases. Notably, a significant proportion of cases remained without potential pathogenic variants. CONCLUSIONS Our findings confirm the complex genetic landscape of hearing loss and the limitations of WES in achieving a 100% diagnostic rate, especially in conditions characterized by genetic heterogeneity. These results contribute to our understanding of the genetic basis of hearing loss and emphasize the need for further research and comprehensive genetic analyses to elucidate the underlying causes of this condition.
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Affiliation(s)
- Abdelaziz Tlili
- Department of Applied Biology, College of Sciences, University of Sharjah, Building W8 Room 107, P.O. Box: 27272, Sharjah, United Arab Emirates.
- Human Genetics and Stem Cell Laboratory, Research Institute of Sciences and Engineering, University of Sharjah, Sharjah, United Arab Emirates.
| | - Mona Mahfood
- Department of Applied Biology, College of Sciences, University of Sharjah, Building W8 Room 107, P.O. Box: 27272, Sharjah, United Arab Emirates
| | - Abdullah Al Mutery
- Department of Applied Biology, College of Sciences, University of Sharjah, Building W8 Room 107, P.O. Box: 27272, Sharjah, United Arab Emirates
| | - Jihen Chouchen
- Human Genetics and Stem Cell Laboratory, Research Institute of Sciences and Engineering, University of Sharjah, Sharjah, United Arab Emirates
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4
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Töpf A, Cox D, Zaharieva IT, Di Leo V, Sarparanta J, Jonson PH, Sealy IM, Smolnikov A, White RJ, Vihola A, Savarese M, Merteroglu M, Wali N, Laricchia KM, Venturini C, Vroling B, Stenton SL, Cummings BB, Harris E, Marini-Bettolo C, Diaz-Manera J, Henderson M, Barresi R, Duff J, England EM, Patrick J, Al-Husayni S, Biancalana V, Beggs AH, Bodi I, Bommireddipalli S, Bönnemann CG, Cairns A, Chiew MT, Claeys KG, Cooper ST, Davis MR, Donkervoort S, Erasmus CE, Fassad MR, Genetti CA, Grosmann C, Jungbluth H, Kamsteeg EJ, Lornage X, Löscher WN, Malfatti E, Manzur A, Martí P, Mongini TE, Muelas N, Nishikawa A, O'Donnell-Luria A, Ogonuki N, O'Grady GL, O'Heir E, Paquay S, Phadke R, Pletcher BA, Romero NB, Schouten M, Shah S, Smuts I, Sznajer Y, Tasca G, Taylor RW, Tuite A, Van den Bergh P, VanNoy G, Voermans NC, Wanschitz JV, Wraige E, Yoshimura K, Oates EC, Nakagawa O, Nishino I, Laporte J, Vilchez JJ, MacArthur DG, Sarkozy A, Cordell HJ, Udd B, Busch-Nentwich EM, Muntoni F, Straub V. Digenic inheritance involving a muscle-specific protein kinase and the giant titin protein causes a skeletal muscle myopathy. Nat Genet 2024; 56:395-407. [PMID: 38429495 PMCID: PMC10937387 DOI: 10.1038/s41588-023-01651-0] [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: 03/29/2021] [Accepted: 12/19/2023] [Indexed: 03/03/2024]
Abstract
In digenic inheritance, pathogenic variants in two genes must be inherited together to cause disease. Only very few examples of digenic inheritance have been described in the neuromuscular disease field. Here we show that predicted deleterious variants in SRPK3, encoding the X-linked serine/argenine protein kinase 3, lead to a progressive early onset skeletal muscle myopathy only when in combination with heterozygous variants in the TTN gene. The co-occurrence of predicted deleterious SRPK3/TTN variants was not seen among 76,702 healthy male individuals, and statistical modeling strongly supported digenic inheritance as the best-fitting model. Furthermore, double-mutant zebrafish (srpk3-/-; ttn.1+/-) replicated the myopathic phenotype and showed myofibrillar disorganization. Transcriptome data suggest that the interaction of srpk3 and ttn.1 in zebrafish occurs at a post-transcriptional level. We propose that digenic inheritance of deleterious changes impacting both the protein kinase SRPK3 and the giant muscle protein titin causes a skeletal myopathy and might serve as a model for other genetic diseases.
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Affiliation(s)
- Ana Töpf
- John Walton Muscular Dystrophy Research Centre, Translational and Clinical Research Institute, Newcastle University and Newcastle Hospitals NHS Foundation Trust, Newcastle upon Tyne, UK.
| | - Dan Cox
- John Walton Muscular Dystrophy Research Centre, Translational and Clinical Research Institute, Newcastle University and Newcastle Hospitals NHS Foundation Trust, Newcastle upon Tyne, UK
| | - Irina T Zaharieva
- Dubowitz Neuromuscular Centre, UCL Great Ormond Street Institute of Child Health & Great Ormond Street Hospital, London, UK
| | - Valeria Di Leo
- John Walton Muscular Dystrophy Research Centre, Translational and Clinical Research Institute, Newcastle University and Newcastle Hospitals NHS Foundation Trust, Newcastle upon Tyne, UK
- Department of Life Sciences, University of Trieste, Trieste, Italy
| | - Jaakko Sarparanta
- Folkhälsan Research Center, Helsinki, Finland
- Department of Medical and Clinical Genetics, Medicum, University of Helsinki, Helsinki, Finland
| | - Per Harald Jonson
- Folkhälsan Research Center, Helsinki, Finland
- Department of Medical and Clinical Genetics, Medicum, University of Helsinki, Helsinki, Finland
| | - Ian M Sealy
- School of Biological and Behavioural Sciences, Queen Mary University of London, London, UK
- Cambridge Institute of Therapeutic Immunology & Infectious Disease (CITIID), Department of Medicine, Jeffrey Cheah Biomedical Centre, University of Cambridge, Cambridge, UK
| | - Andrei Smolnikov
- School of Biotechnology and Biomolecular Sciences, University of New South Wales, Sydney, New South Wales, Australia
| | - Richard J White
- School of Biological and Behavioural Sciences, Queen Mary University of London, London, UK
- Cambridge Institute of Therapeutic Immunology & Infectious Disease (CITIID), Department of Medicine, Jeffrey Cheah Biomedical Centre, University of Cambridge, Cambridge, UK
| | - Anna Vihola
- Folkhälsan Research Center, Helsinki, Finland
- Department of Medical and Clinical Genetics, Medicum, University of Helsinki, Helsinki, Finland
- Neuromuscular Research Centre, Tampere University and University Hospital, Tampere, Finland
| | - Marco Savarese
- Folkhälsan Research Center, Helsinki, Finland
- Department of Medical and Clinical Genetics, Medicum, University of Helsinki, Helsinki, Finland
| | - Munise Merteroglu
- School of Biological and Behavioural Sciences, Queen Mary University of London, London, UK
- Laboratory of Angiogenesis and Cancer Metabolism, Department of Biology, University of Padua, Padua, Italy
| | - Neha Wali
- Wellcome Sanger Institute, Wellcome Genome Campus, Hinxton, UK
| | - Kristen M Laricchia
- Program in Medical and Population Genetics, Broad Institute of MIT and Harvard, Cambridge, MA, USA
- Analytic and Translational Genetics Unit, Massachusetts General Hospital, Boston, MA, USA
| | - Cristina Venturini
- Division of Infection and Immunity, University College London, London, UK
| | | | - Sarah L Stenton
- Program in Medical and Population Genetics, Broad Institute of MIT and Harvard, Cambridge, MA, USA
- Division of Genetics & Genomics, Department of Pediatrics, Boston Children's Hospital, Boston, MA, USA
| | - Beryl B Cummings
- Laboratory of Angiogenesis and Cancer Metabolism, Department of Biology, University of Padua, Padua, Italy
| | - Elizabeth Harris
- John Walton Muscular Dystrophy Research Centre, Translational and Clinical Research Institute, Newcastle University and Newcastle Hospitals NHS Foundation Trust, Newcastle upon Tyne, UK
- Northern Genetics Service, Institute of Genetics Medicine, Newcastle upon Tyne, UK
| | - Chiara Marini-Bettolo
- John Walton Muscular Dystrophy Research Centre, Translational and Clinical Research Institute, Newcastle University and Newcastle Hospitals NHS Foundation Trust, Newcastle upon Tyne, UK
| | - Jordi Diaz-Manera
- John Walton Muscular Dystrophy Research Centre, Translational and Clinical Research Institute, Newcastle University and Newcastle Hospitals NHS Foundation Trust, Newcastle upon Tyne, UK
| | - Matt Henderson
- Muscle Immunoanalysis Unit, Newcastle upon Tyne Hospitals NHS Foundation Trust, Newcastle upon Tyne, UK
| | | | - Jennifer Duff
- John Walton Muscular Dystrophy Research Centre, Translational and Clinical Research Institute, Newcastle University and Newcastle Hospitals NHS Foundation Trust, Newcastle upon Tyne, UK
| | - Eleina M England
- Program in Medical and Population Genetics, Broad Institute of MIT and Harvard, Cambridge, MA, USA
| | - Jane Patrick
- Wellcome Sanger Institute, Wellcome Genome Campus, Hinxton, UK
| | - Sundos Al-Husayni
- The Manton Center for Orphan Disease Research, Division of Genetics and Genomics, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Valerie Biancalana
- Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), Inserm U1258, Cnrs UMR7104, Université de Strasbourg, Illkirch, France
| | - Alan H Beggs
- The Manton Center for Orphan Disease Research, Division of Genetics and Genomics, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Istvan Bodi
- Department of Clinical Neuropathology, King's College Hospital NHS Foundation Trust, London, UK
| | - Shobhana Bommireddipalli
- Kids Neuroscience Centre, the Children's Hospital at Westmead, the University of Sydney and the Children's Medical Research Institute, Westmead, New South Wales, Australia
| | - Carsten G Bönnemann
- Neuromuscular and Neurogenetic Disorders of Childhood Section, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, USA
| | - Anita Cairns
- Neurosciences Department, Queensland Children's Hospital, Brisbane, Queensland, Australia
| | - Mei-Ting Chiew
- Department of Diagnostic Genomics, PathWest Laboratory Medicine, Perth, Western Australia, Australia
| | - Kristl G Claeys
- Department of Neurology, University Hospitals Leuven, Leuven, Belgium
- Laboratory for Muscle Diseases and Neuropathies, Department of Neurosciences, KU Leuven, Leuven, Belgium
| | - Sandra T Cooper
- Kids Neuroscience Centre, the Children's Hospital at Westmead, the University of Sydney and the Children's Medical Research Institute, Westmead, New South Wales, Australia
| | - Mark R Davis
- Department of Diagnostic Genomics, PathWest Laboratory Medicine, Perth, Western Australia, Australia
| | - Sandra Donkervoort
- Neuromuscular and Neurogenetic Disorders of Childhood Section, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, USA
| | - Corrie E Erasmus
- Department of Paediatric Neurology, Donders Institute for Brain, Cognition and Behavior, Radboud University Medical Centre, Amalia Children's Hospital, Nijmegen, The Netherlands
| | - Mahmoud R Fassad
- Wellcome Centre for Mitochondrial Research, Translational and Clinical Research Institute, Faculty of Medical Sciences, Newcastle University, Newcastle upon Tyne, UK
- NHS Highly Specialised Service for Rare Mitochondrial Disorders, Newcastle upon Tyne Hospitals NHS Foundation Trust, Newcastle upon Tyne, UK
| | - Casie A Genetti
- The Manton Center for Orphan Disease Research, Division of Genetics and Genomics, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Carla Grosmann
- Department of Neurology, Rady Children's Hospital University of California San Diego, San Diego, CA, USA
| | - Heinz Jungbluth
- Department of Paediatric Neurology, Neuromuscular Service, Evelina's Children Hospital, Guy's & St. Thomas' Hospital NHS Foundation Trust, London, UK
- Randall Centre for Cell and Molecular Biophysics, Muscle Signalling Section, Faculty of Life Sciences and Medicine (FoLSM), King's College London, London, UK
| | - Erik-Jan Kamsteeg
- Department of Human Genetics, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Xavière Lornage
- Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), Inserm U1258, Cnrs UMR7104, Université de Strasbourg, Illkirch, France
| | - Wolfgang N Löscher
- Department of Neurology, Medical University Innsbruck, Innsbruck, Austria
| | - Edoardo Malfatti
- APHP, Neuromuscular Reference Center Nord-Est-Ile-de-France, Henri Mondor Hospital, Université Paris Est, U955, INSERM, Creteil, France
| | - Adnan Manzur
- Dubowitz Neuromuscular Centre, UCL Great Ormond Street Institute of Child Health & Great Ormond Street Hospital, London, UK
| | - Pilar Martí
- Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), Madrid, Spain
- Neuromuscular Research Group, IIS La Fe, Valencia, Spain
| | - Tiziana E Mongini
- Department of Neurosciences Rita Levi Montalcini, Università degli Studi di Torino, Torino, Italy
| | - Nuria Muelas
- Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), Madrid, Spain
- Neuromuscular Research Group, IIS La Fe, Valencia, Spain
- Department of Medicine, Universitat de Valencia, Valencia, Spain
- Neuromuscular Diseases Unit, Neurology Department, Hospital Universitari I Politècnic La Fe, Valencia, Spain
| | - Atsuko Nishikawa
- Department of Neuromuscular Research, National Institute of Neuroscience, National Center of Neurology and Psychiatry, Tokyo, Japan
| | - Anne O'Donnell-Luria
- Program in Medical and Population Genetics, Broad Institute of MIT and Harvard, Cambridge, MA, USA
- Division of Genetics & Genomics, Department of Pediatrics, Boston Children's Hospital, Boston, MA, USA
| | | | - Gina L O'Grady
- Starship Children's Health, Auckland District Health Board, Auckland, New Zealand
| | - Emily O'Heir
- Program in Medical and Population Genetics, Broad Institute of MIT and Harvard, Cambridge, MA, USA
| | - Stéphanie Paquay
- Cliniques Universitaires St-Luc, Centre de Référence Neuromusculaire, Université de Louvain, Brussels, Belgium
| | - Rahul Phadke
- Dubowitz Neuromuscular Centre, UCL Great Ormond Street Institute of Child Health & Great Ormond Street Hospital, London, UK
| | - Beth A Pletcher
- Division of Clinical Genetics, Department of Pediatrics, Rutgers New Jersey Medical School, Newark, NJ, USA
| | - Norma B Romero
- Neuromuscular Morphology Unit, Myology Institute, Sorbonne Université, Centre de Référence de Pathologie Neuromusculaire Nord/Est/Ile-de-France (APHP), GH Pitié-Salpêtrière, Paris, France
| | - Meyke Schouten
- Department of Human Genetics, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Snehal Shah
- Department of Neurology, Perth Children's Hospital, Nedlands, Western Australia, Australia
| | - Izelle Smuts
- Department of Paediatrics, Steve Biko Academic Hospital, University of Pretoria, Pretoria, South Africa
| | - Yves Sznajer
- Center for Human Genetic, Cliniques Universitaires Saint Luc, UCLouvain, Brussels, Belgium
| | - Giorgio Tasca
- John Walton Muscular Dystrophy Research Centre, Translational and Clinical Research Institute, Newcastle University and Newcastle Hospitals NHS Foundation Trust, Newcastle upon Tyne, UK
| | - Robert W Taylor
- Wellcome Centre for Mitochondrial Research, Translational and Clinical Research Institute, Faculty of Medical Sciences, Newcastle University, Newcastle upon Tyne, UK
- NHS Highly Specialised Service for Rare Mitochondrial Disorders, Newcastle upon Tyne Hospitals NHS Foundation Trust, Newcastle upon Tyne, UK
| | - Allysa Tuite
- Division of Clinical Genetics, Department of Pediatrics, Rutgers New Jersey Medical School, Newark, NJ, USA
| | - Peter Van den Bergh
- Cliniques Universitaires St-Luc, Centre de Référence Neuromusculaire, Université de Louvain, Brussels, Belgium
| | - Grace VanNoy
- Program in Medical and Population Genetics, Broad Institute of MIT and Harvard, Cambridge, MA, USA
| | - Nicol C Voermans
- Department of Neurology, Donders Institute for Brain, Cognition and Behavior, Radboud University Medical Centre, Nijmegen, The Netherlands
| | - Julia V Wanschitz
- Department of Neurology, Medical University Innsbruck, Innsbruck, Austria
| | - Elizabeth Wraige
- Evelina's Children Hospital, Guy's & St. Thomas' Hospital NHS Foundation Trust, London, UK
| | | | - Emily C Oates
- School of Biotechnology and Biomolecular Sciences, University of New South Wales, Sydney, New South Wales, Australia
| | - Osamu Nakagawa
- Department of Molecular Physiology, National Cerebral and Cardiovascular Center Research Institute, Osaka, Japan
| | - Ichizo Nishino
- Department of Neuromuscular Research, National Institute of Neuroscience, National Center of Neurology and Psychiatry, Tokyo, Japan
| | - Jocelyn Laporte
- Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), Inserm U1258, Cnrs UMR7104, Université de Strasbourg, Illkirch, France
| | - Juan J Vilchez
- Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), Madrid, Spain
- Neuromuscular Research Group, IIS La Fe, Valencia, Spain
| | - Daniel G MacArthur
- Program in Medical and Population Genetics, Broad Institute of MIT and Harvard, Cambridge, MA, USA
- Centre for Population Genomics, Garvan Institute of Medical Research and UNSW, Sydney, New South Wales, Australia
- Centre for Population Genomics, Murdoch Children's Research Institute, Melbourne, Victoria, Australia
| | - Anna Sarkozy
- Dubowitz Neuromuscular Centre, UCL Great Ormond Street Institute of Child Health & Great Ormond Street Hospital, London, UK
| | - Heather J Cordell
- Population Health Sciences Institute, Faculty of Medical Sciences, Newcastle University, Newcastle upon Tyne, UK
| | - Bjarne Udd
- Folkhälsan Research Center, Helsinki, Finland
- Department of Medical and Clinical Genetics, Medicum, University of Helsinki, Helsinki, Finland
- Neuromuscular Research Centre, Tampere University and University Hospital, Tampere, Finland
| | - Elisabeth M Busch-Nentwich
- School of Biological and Behavioural Sciences, Queen Mary University of London, London, UK
- Cambridge Institute of Therapeutic Immunology & Infectious Disease (CITIID), Department of Medicine, Jeffrey Cheah Biomedical Centre, University of Cambridge, Cambridge, UK
| | - Francesco Muntoni
- Dubowitz Neuromuscular Centre, UCL Great Ormond Street Institute of Child Health & Great Ormond Street Hospital, London, UK
- NIHR Great Ormond Street Hospital Biomedical Research Centre, Great Ormond Street Institute of Child Health, UCL & Great Ormond Street Hospital Trust, London, UK
| | - Volker Straub
- John Walton Muscular Dystrophy Research Centre, Translational and Clinical Research Institute, Newcastle University and Newcastle Hospitals NHS Foundation Trust, Newcastle upon Tyne, UK.
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5
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Chiang YT, Lin PH, Lo MY, Chen HL, Lee CY, Tsai CY, Lin YH, Tsai SF, Liu TC, Hsu CJ, Chen PL, Hsu JSJ, Wu CC. Genetic Factors Contribute to the Phenotypic Variability in GJB2-Related Hearing Impairment. J Mol Diagn 2023; 25:827-837. [PMID: 37683890 DOI: 10.1016/j.jmoldx.2023.07.005] [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: 01/18/2023] [Revised: 07/19/2023] [Accepted: 07/24/2023] [Indexed: 09/10/2023] Open
Abstract
Recessive variants in GJB2 are the most important genetic cause of sensorineural hearing impairment (SNHI) worldwide. Phenotypes vary significantly in GJB2-related SNHI, even in patients with identical variants. For instance, patients homozygous for the GJB2 p.V37I variant, which is highly prevalent in the Asian populations, usually present with mild-to-moderate SNHI; yet severe-to-profound SNHI is occasionally observed in approximately 10% of p.V37I homozygotes. To investigate the genomic underpinnings of the phenotypic variability, we performed next-generation sequencing of GJB2 and other deafness genes in 63 p.V37I homozygotes with extreme phenotypic severities. Additional pathogenic variants of other deafness genes were identified in five of the 35 patients with severe-to-profound SNHI. Furthermore, case-control association analyses were conducted for 30 unrelated p.V37I homozygotes with severe-to-profound SNHI against 28 p.V37I homozygotes with mild-to-moderate SNHI, and 120 population controls from the Taiwan Biobank. The severe-to-profound group exhibited a higher frequency of the crystallin lambda 1 (CRYL1) variant (rs14236), located upstream of GJB2, than the mild-to-moderate and Taiwan Biobank groups. Our results demonstrated that pathogenic variants in other deafness genes and a possible modifier, the CRYL1 rs14236 variant, may contribute to phenotypic variability in GJB2-realted SNHI, highlighting the importance of comprehensive genomic surveys to delineate the genotype-phenotype correlations.
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Affiliation(s)
- Yu-Ting Chiang
- Graduate Institute of Medical Genomics and Proteomics, College of Medicine, National Taiwan University, Taipei, Taiwan; Graduate Institute of Clinical Medicine, College of Medicine, National Taiwan University, Taipei, Taiwan
| | - Pei-Hsuan Lin
- Graduate Institute of Clinical Medicine, College of Medicine, National Taiwan University, Taipei, Taiwan; Department of Otolaryngology Head and Neck Surgery, National Taiwan University Hospital, Taipei, Taiwan
| | - Ming-Yu Lo
- Graduate Institute of Clinical Medicine, College of Medicine, National Taiwan University, Taipei, Taiwan
| | - Hsin-Lin Chen
- Graduate Institute of Clinical Medicine, College of Medicine, National Taiwan University, Taipei, Taiwan; Department of Surgical Oncology, National Taiwan University Cancer Center, Taipei, Taiwan
| | - Chen-Yu Lee
- Graduate Institute of Clinical Medicine, College of Medicine, National Taiwan University, Taipei, Taiwan; Department of Medical Research, National Taiwan University Hospital Hsin-Chu Branch, Hsinchu, Taiwan
| | - Cheng-Yu Tsai
- Graduate Institute of Medical Genomics and Proteomics, College of Medicine, National Taiwan University, Taipei, Taiwan; Graduate Institute of Clinical Medicine, College of Medicine, National Taiwan University, Taipei, Taiwan
| | - Yin-Hung Lin
- Graduate Institute of Clinical Medicine, College of Medicine, National Taiwan University, Taipei, Taiwan
| | - Shih-Feng Tsai
- Department of Life Sciences and Institute of Genome Sciences, National Yang-Ming University, Taipei, Taiwan; Institute of Molecular and Genomic Medicine, National Health Research Institutes, Miaoli, Taiwan
| | - Tien-Chen Liu
- Graduate Institute of Clinical Medicine, College of Medicine, National Taiwan University, Taipei, Taiwan
| | - Chuan-Jen Hsu
- Graduate Institute of Clinical Medicine, College of Medicine, National Taiwan University, Taipei, Taiwan; Department of Otolaryngology, Taichung Tzu Chi Hospital, Buddhist Tzu Chi Medical Foundation, Taichung, Taiwan
| | - Pei-Lung Chen
- Graduate Institute of Medical Genomics and Proteomics, College of Medicine, National Taiwan University, Taipei, Taiwan; Department of Otolaryngology Head and Neck Surgery, National Taiwan University Hospital, Taipei, Taiwan; Department of Medical Genetics, National Taiwan University Hospital, Taipei, Taiwan
| | - Jacob Shu-Jui Hsu
- Graduate Institute of Medical Genomics and Proteomics, College of Medicine, National Taiwan University, Taipei, Taiwan.
| | - Chen-Chi Wu
- Graduate Institute of Clinical Medicine, College of Medicine, National Taiwan University, Taipei, Taiwan; Department of Medical Research, National Taiwan University Hospital Hsin-Chu Branch, Hsinchu, Taiwan
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6
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Tao Y, Lamas V, Du W, Zhu W, Li Y, Whittaker MN, Zuris JA, Thompson DB, Rameshbabu AP, Shu Y, Gao X, Hu JH, Pei C, Kong WJ, Liu X, Wu H, Kleinstiver BP, Liu DR, Chen ZY. Treatment of monogenic and digenic dominant genetic hearing loss by CRISPR-Cas9 ribonucleoprotein delivery in vivo. Nat Commun 2023; 14:4928. [PMID: 37582836 PMCID: PMC10427623 DOI: 10.1038/s41467-023-40476-7] [Citation(s) in RCA: 13] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2022] [Accepted: 07/31/2023] [Indexed: 08/17/2023] Open
Abstract
Mutations in Atp2b2, an outer hair cell gene, cause dominant hearing loss in humans. Using a mouse model Atp2b2Obl/+, with a dominant hearing loss mutation (Oblivion), we show that liposome-mediated in vivo delivery of CRISPR-Cas9 ribonucleoprotein complexes leads to specific editing of the Obl allele. Large deletions encompassing the Obl locus and indels were identified as the result of editing. In vivo genome editing promotes outer hair cell survival and restores their function, leading to hearing recovery. We further show that in a double-dominant mutant mouse model, in which the Tmc1 Beethoven mutation and the Atp2b2 Oblivion mutation cause digenic genetic hearing loss, Cas9/sgRNA delivery targeting both mutations leads to partial hearing recovery. These findings suggest that liposome-RNP delivery can be used as a strategy to recover hearing with dominant mutations in OHC genes and with digenic mutations in the auditory hair cells, potentially expanding therapeutics of gene editing to treat hearing loss.
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Affiliation(s)
- Yong Tao
- Department of Otolaryngology-Head and Neck Surgery, Graduate Program in Speech and Hearing Bioscience and Technology and Program in Neuroscience, Harvard Medical School, Boston, MA, 02115, USA
- Eaton-Peabody Laboratory, Massachusetts Eye and Ear Infirmary, 243 Charles St., Boston, MA, 02114, USA
- Department of Otolaryngology-Head and Neck Surgery, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, 200011, China
| | - Veronica Lamas
- Department of Otolaryngology-Head and Neck Surgery, Graduate Program in Speech and Hearing Bioscience and Technology and Program in Neuroscience, Harvard Medical School, Boston, MA, 02115, USA
- Eaton-Peabody Laboratory, Massachusetts Eye and Ear Infirmary, 243 Charles St., Boston, MA, 02114, USA
- Salk Institute for Biological Studies, La Jolla, CA, 92037, USA
| | - Wan Du
- Department of Otolaryngology-Head and Neck Surgery, Graduate Program in Speech and Hearing Bioscience and Technology and Program in Neuroscience, Harvard Medical School, Boston, MA, 02115, USA
- Eaton-Peabody Laboratory, Massachusetts Eye and Ear Infirmary, 243 Charles St., Boston, MA, 02114, USA
| | - Wenliang Zhu
- Department of Otolaryngology-Head and Neck Surgery, Graduate Program in Speech and Hearing Bioscience and Technology and Program in Neuroscience, Harvard Medical School, Boston, MA, 02115, USA
- Eaton-Peabody Laboratory, Massachusetts Eye and Ear Infirmary, 243 Charles St., Boston, MA, 02114, USA
| | - Yiran Li
- Department of Otolaryngology-Head and Neck Surgery, Graduate Program in Speech and Hearing Bioscience and Technology and Program in Neuroscience, Harvard Medical School, Boston, MA, 02115, USA
- Eaton-Peabody Laboratory, Massachusetts Eye and Ear Infirmary, 243 Charles St., Boston, MA, 02114, USA
- C.S. Mott Children's Hospital, Ann Harbor, MI, USA
| | - Madelynn N Whittaker
- Center for Genomic Medicine, Massachusetts General Hospital, Boston, MA, 02114, USA
- Department of Pathology, Massachusetts General hospital, Boston, MA, 02114, USA
| | - John A Zuris
- Merkin Institute of Transformative Technologies in Healthcare, Broad Institute of MIT and Harvard, Cambridge, MA, USA
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA, USA
- Howard Hughes Medical Institute, Harvard University, Cambridge, MA, USA
| | - David B Thompson
- Merkin Institute of Transformative Technologies in Healthcare, Broad Institute of MIT and Harvard, Cambridge, MA, USA
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA, USA
- Howard Hughes Medical Institute, Harvard University, Cambridge, MA, USA
| | - Arun Prabhu Rameshbabu
- Department of Otolaryngology-Head and Neck Surgery, Graduate Program in Speech and Hearing Bioscience and Technology and Program in Neuroscience, Harvard Medical School, Boston, MA, 02115, USA
- Eaton-Peabody Laboratory, Massachusetts Eye and Ear Infirmary, 243 Charles St., Boston, MA, 02114, USA
| | - Yilai Shu
- Department of Otolaryngology-Head and Neck Surgery, Graduate Program in Speech and Hearing Bioscience and Technology and Program in Neuroscience, Harvard Medical School, Boston, MA, 02115, USA
- Eaton-Peabody Laboratory, Massachusetts Eye and Ear Infirmary, 243 Charles St., Boston, MA, 02114, USA
- ENT Institute and Department of Otorhinolaryngology, Eye & ENT Hospital, State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, NHC Key Laboratory of Hearing Medicine, Institutes of Biomedical Sciences, Fudan University, Shanghai, 200031, China
| | - Xue Gao
- Merkin Institute of Transformative Technologies in Healthcare, Broad Institute of MIT and Harvard, Cambridge, MA, USA
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA, USA
- Howard Hughes Medical Institute, Harvard University, Cambridge, MA, USA
| | - Johnny H Hu
- Merkin Institute of Transformative Technologies in Healthcare, Broad Institute of MIT and Harvard, Cambridge, MA, USA
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA, USA
- Howard Hughes Medical Institute, Harvard University, Cambridge, MA, USA
| | - Charles Pei
- Eaton-Peabody Laboratory, Massachusetts Eye and Ear Infirmary, 243 Charles St., Boston, MA, 02114, USA
| | - Wei-Jia Kong
- Department of Otorhinolaryngology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Xuezhong Liu
- Department of Otolaryngology, University of Miami Miller School of Medicine, Miami, FL, USA
| | - Hao Wu
- Department of Otolaryngology-Head and Neck Surgery, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, 200011, China
| | - Benjamin P Kleinstiver
- Center for Genomic Medicine, Massachusetts General Hospital, Boston, MA, 02114, USA
- Department of Pathology, Massachusetts General hospital, Boston, MA, 02114, USA
- Department of Pathology, Harvard Medical School, Boston, MA, 02115, USA
| | - David R Liu
- Merkin Institute of Transformative Technologies in Healthcare, Broad Institute of MIT and Harvard, Cambridge, MA, USA.
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA, USA.
- Howard Hughes Medical Institute, Harvard University, Cambridge, MA, USA.
| | - Zheng-Yi Chen
- Department of Otolaryngology-Head and Neck Surgery, Graduate Program in Speech and Hearing Bioscience and Technology and Program in Neuroscience, Harvard Medical School, Boston, MA, 02115, USA.
- Eaton-Peabody Laboratory, Massachusetts Eye and Ear Infirmary, 243 Charles St., Boston, MA, 02114, USA.
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7
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Zhou M, Zheng M, Zhou X, Tian S, Yang X, Ning Y, Li Y, Zhang S. The roles of connexins and gap junctions in the progression of cancer. Cell Commun Signal 2023; 21:8. [PMID: 36639804 PMCID: PMC9837928 DOI: 10.1186/s12964-022-01009-9] [Citation(s) in RCA: 20] [Impact Index Per Article: 20.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2022] [Accepted: 12/03/2022] [Indexed: 01/15/2023] Open
Abstract
Gap junctions (GJs), which are composed of connexins (Cxs), provide channels for direct information exchange between cells. Cx expression has a strong spatial specificity; however, its influence on cell behavior and information exchange between cells cannot be ignored. A variety of factors in organisms can modulate Cxs and subsequently trigger a series of responses that have important effects on cellular behavior. The expression and function of Cxs and the number and function of GJs are in dynamic change. Cxs have been characterized as tumor suppressors in the past, but recent studies have highlighted the critical roles of Cxs and GJs in cancer pathogenesis. The complex mechanism underlying Cx and GJ involvement in cancer development is a major obstacle to the evolution of therapy targeting Cxs. In this paper, we review the post-translational modifications of Cxs, the interactions of Cxs with several chaperone proteins, and the effects of Cxs and GJs on cancer. Video Abstract.
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Affiliation(s)
- Mingming Zhou
- grid.265021.20000 0000 9792 1228Graduate School, Tianjin Medical University, Tianjin, 300070 People’s Republic of China
| | - Minying Zheng
- Department of Pathology, Tianjin Union Medical Center, Nankai University, Tianjin, 300121 People’s Republic of China
| | - Xinyue Zhou
- grid.265021.20000 0000 9792 1228Graduate School, Tianjin Medical University, Tianjin, 300070 People’s Republic of China
| | - Shifeng Tian
- grid.265021.20000 0000 9792 1228Graduate School, Tianjin Medical University, Tianjin, 300070 People’s Republic of China
| | - Xiaohui Yang
- grid.216938.70000 0000 9878 7032Nankai University School of Medicine, Nankai University, Tianjin, 300071 People’s Republic of China
| | - Yidi Ning
- grid.216938.70000 0000 9878 7032Nankai University School of Medicine, Nankai University, Tianjin, 300071 People’s Republic of China
| | - Yuwei Li
- grid.417031.00000 0004 1799 2675Department of Colorectal Surgery, Tianjin Union Medical Center, Tianjin, 300121 People’s Republic of China
| | - Shiwu Zhang
- Department of Pathology, Tianjin Union Medical Center, Nankai University, Tianjin, 300121 People’s Republic of China
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8
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Stepanova AA, Ismagilova OR, Galeeva NM, Markova TG, Tavartkiladze GA, Kvlividze O, Polyakov AV. Molecular Genetic Study of the Causes of Nonsyndromic Sensorineural Hearing Loss in Patients from Georgia. RUSS J GENET+ 2022. [DOI: 10.1134/s1022795422050106] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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9
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Yang L, Guo Q, Leng J, Wang K, Ding Y. Late onset of type 2 diabetes is associated with mitochondrial tRNA Trp A5514G and tRNA Ser(AGY) C12237T mutations. J Clin Lab Anal 2021; 36:e24102. [PMID: 34811812 PMCID: PMC8761459 DOI: 10.1002/jcla.24102] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2021] [Revised: 10/19/2021] [Accepted: 10/26/2021] [Indexed: 12/16/2022] Open
Abstract
Background Mitochondrial dysfunctions caused by mitochondrial DNA (mtDNA) pathogenic mutations play putative roles in type 2 diabetes mellitus (T2DM) progression. But the underlying mechanism remains poorly understood. Methods A large Chinese family with maternally inherited diabetes and deafness (MIDD) underwent clinical, genetic, and molecular assessment. PCR and sequence analysis are carried out to detect mtDNA variants in affected family members, in addition, phylogenetic conservation analysis, haplogroup classification, and pathogenicity scoring system are performed. Moreover, the GJB2, GJB3, GJB6, and TRMU genes mutations are screened by PCR‐Sanger sequencing. Results Six of 18 matrilineal subjects manifested different clinical phenotypes of diabetes. The average age at onset of diabetic patients is 52 years. Screening for the entire mitochondrial genomes suggests the co‐existence of two possibly pathogenic mutations: tRNATrp A5514G and tRNASer(AGY) C12237T, which belongs to East Asia haplogroup G2a. By molecular level, m.A5514G mutation resides at acceptor stem of tRNATrp (position 3), which is critical for steady‐state level of tRNATrp. Conversely, m.C12237T mutation occurs in the variable region of tRNASer(AGY) (position 31), which creates a novel base‐pairing (11A‐31T). Thus, the mitochondrial dysfunctions caused by tRNATrp A5514G and tRNASer(AGY) C12237T mutations, may be associated with T2DM in this pedigree. But we do not find any functional mutations in those nuclear genes. Conclusion Our findings suggest that m.A5514G and m.C12337T mutations are associated with T2DM, screening for mt‐tRNA mutations is useful for molecular diagnosis and prevention of mitochondrial diabetes.
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Affiliation(s)
- Liuchun Yang
- Central Laboratory, the Fourth School of Clinical Medicine, Zhejiang Chinese Medical University, Hangzhou, China
| | - Qinxian Guo
- Central Laboratory, the Affiliated Hangzhou First People's Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Jianhang Leng
- Central Laboratory, the Affiliated Hangzhou First People's Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Keyi Wang
- Central Laboratory, the Fourth School of Clinical Medicine, Zhejiang Chinese Medical University, Hangzhou, China.,Central Laboratory, the Affiliated Hangzhou First People's Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Yu Ding
- Central Laboratory, the Affiliated Hangzhou First People's Hospital, Zhejiang University School of Medicine, Hangzhou, China
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10
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Gap Junction Channelopathies and Calmodulinopathies. Do Disease-Causing Calmodulin Mutants Affect Direct Cell-Cell Communication? Int J Mol Sci 2021; 22:ijms22179169. [PMID: 34502077 PMCID: PMC8431743 DOI: 10.3390/ijms22179169] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2021] [Revised: 08/19/2021] [Accepted: 08/21/2021] [Indexed: 11/24/2022] Open
Abstract
The cloning of connexins cDNA opened the way to the field of gap junction channelopathies. Thus far, at least 35 genetic diseases, resulting from mutations of 11 different connexin genes, are known to cause numerous structural and functional defects in the central and peripheral nervous system as well as in the heart, skin, eyes, teeth, ears, bone, hair, nails and lymphatic system. While all of these diseases are due to connexin mutations, minimal attention has been paid to the potential diseases of cell–cell communication caused by mutations of Cx-associated molecules. An important Cx accessory protein is calmodulin (CaM), which is the major regulator of gap junction channel gating and a molecule relevant to gap junction formation. Recently, diseases caused by CaM mutations (calmodulinopathies) have been identified, but thus far calmodulinopathy studies have not considered the potential effect of CaM mutations on gap junction function. The major goal of this review is to raise awareness on the likely role of CaM mutations in defects of gap junction mediated cell communication. Our studies have demonstrated that certain CaM mutants affect gap junction channel gating or expression, so it would not be surprising to learn that CaM mutations known to cause diseases also affect cell communication mediated by gap junction channels.
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11
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Lin YH, Wu PC, Tsai CY, Lin YH, Lo MY, Hsu SJ, Lin PH, Erdenechuluun J, Wu HP, Hsu CJ, Wu CC, Chen PL. Hearing Impairment with Monoallelic GJB2 Variants: A GJB2 Cause or Non-GJB2 Cause? J Mol Diagn 2021; 23:1279-1291. [PMID: 34325055 DOI: 10.1016/j.jmoldx.2021.07.007] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2020] [Revised: 03/23/2021] [Accepted: 07/07/2021] [Indexed: 12/26/2022] Open
Abstract
Recessive variants in GJB2 are the most common genetic cause of sensorineural hearing impairment. However, in many patients, only one variant in the GJB2 coding region is identified using conventional sequencing strategy (eg, Sanger sequencing), resulting in nonconfirmative diagnosis. Conceivably, there might be other unidentified pathogenic variants in the noncoding region of GJB2 or other deafness-causing genes in these patients. To address this, a next-generation sequencing-based diagnostic panel targeting the entire GJB2 gene and the coding regions of 158 other known deafness-causing genes was designed and applied to 95 patients with nonsyndromic sensorineural hearing impairment (including 81 Han Taiwanese and 14 Mongolian patients) in whom only a single GJB2 variant had been detected using conventional Sanger sequencing. The panel confirmed the genetic diagnosis in 24 patients (25.3%). Twenty-two of them had causative variants in several deafness-causing genes other than GJB2, including MYO15A, MYO7A, TECTA, POU4F3, KCNQ4, SLC26A4, OTOF, MT-RNR1, MITF, WFS1, and USH2A. The other two patients had causative variants in GJB2, including a Taiwanese patient with a mosaic maternal uniparental disomy c.235delC variant (approximately 69% mosaicism) and a Mongolian patient with compound heterozygous c.35dupG and c.35delG variants, which occurred at the same site. This study demonstrates the utility of next-generation sequencing in clarifying the genetic diagnosis of hearing-impaired patients with nonconfirmative GJB2 genotypes on conventional genetic examinations.
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Affiliation(s)
- Yi-Hsin Lin
- Department of Otolaryngology, National Taiwan University Hospital, National Taiwan University Hospital, Taipei, Taiwan; Institute of Molecular Medicine, National Taiwan University College of Medicine, Taipei, Taiwan
| | - Ping-Che Wu
- College of Medicine, National Taiwan University, Taipei, Taiwan
| | - Cheng-Yu Tsai
- Department of Otolaryngology, National Taiwan University Hospital, National Taiwan University Hospital, Taipei, Taiwan; Graduate Institutes of Medical Genomic, National Taiwan University College of Medicine, Taipei, Taiwan
| | - Yin-Hung Lin
- Department of Otolaryngology, National Taiwan University Hospital, National Taiwan University Hospital, Taipei, Taiwan; Graduate Institutes of Medical Genomic, National Taiwan University College of Medicine, Taipei, Taiwan
| | - Ming-Yu Lo
- Department of Otolaryngology, National Taiwan University Hospital, National Taiwan University Hospital, Taipei, Taiwan; Institute of Molecular Medicine, National Taiwan University College of Medicine, Taipei, Taiwan
| | - Shu-Jui Hsu
- Graduate Institutes of Medical Genomic, National Taiwan University College of Medicine, Taipei, Taiwan
| | - Pei-Hsuan Lin
- Department of Otolaryngology, National Taiwan University Hospital Yunlin Branch, Yunlin, Taiwan
| | - Jargalkhuu Erdenechuluun
- Department of Otolaryngology, Mongolian National University of Medical Sciences, Ulaanbaatar, Mongolia; The EMJJ Otolaryngology Hospital, Ulaanbaatar, Mongolia
| | - Hung-Pin Wu
- Department of Otolaryngology Head and Neck Surgery, Taichung Tzu Chi Hospital, Buddhist Tzu Chi Medical Foundation, Taichung, Taiwan; School of Medicine, Tzu Chi University, Hualien, Taiwan
| | - Chuan-Jen Hsu
- Department of Otolaryngology, National Taiwan University Hospital, National Taiwan University Hospital, Taipei, Taiwan; Department of Otolaryngology Head and Neck Surgery, Taichung Tzu Chi Hospital, Buddhist Tzu Chi Medical Foundation, Taichung, Taiwan
| | - Chen-Chi Wu
- Department of Otolaryngology, National Taiwan University Hospital, National Taiwan University Hospital, Taipei, Taiwan; Clinical Medicine, National Taiwan University College of Medicine, Taipei, Taiwan.
| | - Pei-Lung Chen
- Institute of Molecular Medicine, National Taiwan University College of Medicine, Taipei, Taiwan; Graduate Institutes of Medical Genomic, National Taiwan University College of Medicine, Taipei, Taiwan; Clinical Medicine, National Taiwan University College of Medicine, Taipei, Taiwan; Department of Medical Genetics, National Taiwan University Hospital, National Taiwan University Hospital, Taipei, Taiwan; Department of Internal Medicine, National Taiwan University Hospital, National Taiwan University Hospital, Taipei, Taiwan.
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12
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Cai L, Liu Y, Xu Y, Yang H, Lv L, Li Y, Chen Q, Lin X, Yang Y, Hu G, Zheng G, Zhou J, Qian Q, Xu MA, Fang J, Ding J, Chen W, Gao J. Multi-Center in-Depth Screening of Neonatal Deafness Genes: Zhejiang, China. Front Genet 2021; 12:637096. [PMID: 34276761 PMCID: PMC8282931 DOI: 10.3389/fgene.2021.637096] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2020] [Accepted: 05/07/2021] [Indexed: 11/13/2022] Open
Abstract
Purpose The conventional genetic screening for deafness involves 9-20 variants from four genes. This study expands screening to analyze the mutation types and frequency of hereditary deafness genes in Zhejiang, China, and explore the significance of in-depth deafness genetic screening in newborns. Methods This was a multi-centre study conducted in 5,120 newborns from 12 major hospitals in the East-West (including mountains and islands) of Zhejiang Province. Concurrent hearing and genetic screening was performed. For genetic testing, 159 variants of 22 genes were screened, including CDH23, COL11A1, DFNA5, DFNB59, DSPP, GJB2, GJB3, KCNJ10, MT-RNR1, MT-TL1, MT-TS1, MYO15A, MYO7A, OTOF, PCDH15, SLC26A4, SOX10, TCOF1, TMC1, USH1G, WFS1, and WHRN using next-generation sequencing. Newborns who failed to have genetic mutations or hearing screening were diagnosed audiologically at the age of 6 months. Results A total of 4,893 newborns (95.57%) have passed the initial hearing screening, and 7 (0.14%) have failed in repeated screening. Of these, 446 (8.71%) newborns carried at least one genetic deafness-associated variant. High-risk pathogenic variants were found in 11 newborns (0.21%) (nine homozygotes and two compound heterozygotes), and eight of these infants have passed the hearing screening. The frequency of mutations in GJB2, GJB3, SLC26A4, 12SrRNA, and TMC1 was 5.43%, 0.59%, 1.91%, 0.98%, and 0.02%, respectively. The positive rate of in-depth screening was significantly increased when compared with 20 variants in four genes of traditional testing, wherein GJB2 was increased by 97.2%, SLC26A4 by 21% and MT-RNR1 by 150%. The most common mutation variants were GJB2c.235delC and SLC26A4c.919-2A > G, followed by GJB2c.299_300delAT. Homoplasmic mutation in MT-RNR1 was the most common, including m.1555A > G, m.961T > C, m.1095T > C. All these infants have passed routine hearing screening. The positive rate of MT-RNR1 mutation was significantly higher in newborns with high-risk factors of maternal pregnancy. Conclusion The positive rate of deafness gene mutations in the Zhejiang region is higher than that of the database, mainly in GJB2c.235delC, SLC26A4 c.919-2A > G, and m.1555A > G variants. The expanded genetic screening in the detection rate of diseasecausing variants was significantly improved. It is helpful in identifying high-risk children for follow-up intervention.
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Affiliation(s)
- Luhang Cai
- Department of Otorhinolaryngology, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Ya Liu
- Department of Otorhinolaryngology, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Yaping Xu
- Department of Otorhinolaryngology, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Hang Yang
- Department of Otorhinolaryngology, Jiangshan People's Hospital, Quzhou, China
| | - Lihui Lv
- Department of Otorhinolaryngology, Fenghua People's Hospital, Ningbo, China
| | - Yang Li
- Department of Obstetrics, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Qiongqiong Chen
- Department of Otorhinolaryngology, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Xiaojiang Lin
- Department of Otorhinolaryngology, Kaihua People's Hospital, Quzhou, China
| | - Yihui Yang
- Department of Otorhinolaryngology, Ningbo Women and Children's Hospital, Ningbo, China
| | - Guangwei Hu
- Department of Otorhinolaryngology, Zhoushan Hospital, Zhoushan, China
| | - Guofeng Zheng
- Department of Otorhinolaryngology, Shaoxing Second Hospital, Shaoxing, China
| | - Jing Zhou
- Department of Otorhinolaryngology, Ruian People's Hospital, Wenzhou, China
| | - Qiyong Qian
- Department of Otorhinolaryngology, Shengzhou People's Hospital, Shaoxing, China
| | - Mei-Ai Xu
- Department of Otorhinolaryngology, Sanmen People's Hospital, Taizhou, China
| | - Jin Fang
- Department of Otorhinolaryngology, Zhejiang Xin'an International Hospital, Jiaxing, China
| | - Jianjun Ding
- Department of Otorhinolaryngology, Linhai First People's Hospital, Taizhou, China
| | - Wei Chen
- Department of Otorhinolaryngology, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Jiong Gao
- Beijing Genomics Institute, Shenzhen, China
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Zhang Q, Qin T, Hu W, Janjua MU, Jin P. Putative Digenic GJB2/MYO7A Inheritance of Hearing Loss Detected in a Patient with 48,XXYY Klinefelter Syndrome. Hum Hered 2021; 85:117-124. [PMID: 34192699 DOI: 10.1159/000516854] [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: 01/09/2021] [Accepted: 04/01/2021] [Indexed: 11/19/2022] Open
Abstract
OBJECTIVES Nonsyndromic hearing loss (NSHL) is the most frequent type of hereditary hearing impairment. Here, we explored the underlying genetic cause of NSHL in a three-generation family using whole-exome sequencing. The proband had concomitant NSHL and rare 48,XXYY Klinefelter syndrome. MATERIAL AND METHODS Genomic DNA was extracted from the peripheral blood of the proband and their family members. Sanger sequencing and pedigree verification were performed on the pathogenic variants filtered by whole-exome sequencing. The function of the variants was analyzed using bioinformatics software. RESULTS The proband was digenic heterozygous for p.V37I in the GJB2 gene and p.L347I in the MYO7A gene. The proband's mother had normal hearing and did not have any variant. The proband's father and uncle both had NSHL and were compound for the GJB2 p.V37I and MYO7A p.L347I variants, thus indicating a possible GJB2/MYO7A digenic inheritance of NSHL. 48,XXYY Klinefelter syndrome was discovered in the proband after the karyotype analysis, while his parents both had normal karyotypes. CONCLUSIONS Our findings reported a putative GJB2/MYO7A digenic inheritance form of hearing loss, expanding the genotype and phenotype spectrum of NSHL. In addition, this is the first report of concomitant NSHL and 48,XXYY syndrome.
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Affiliation(s)
- Qin Zhang
- Department of Endocrinology, The Third Xiangya Hospital, Central South University, Changsha, China
| | - Tiantian Qin
- Department of Endocrinology, The Third Xiangya Hospital, Central South University, Changsha, China
| | - Wenmu Hu
- Department of Endocrinology, The Third Xiangya Hospital, Central South University, Changsha, China
| | - Muhammad Usman Janjua
- Department of Endocrinology, The Third Xiangya Hospital, Central South University, Changsha, China
| | - Ping Jin
- Department of Endocrinology, The Third Xiangya Hospital, Central South University, Changsha, China
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Aliazami F, Farhud D, Zarif-Yeganeh M, Salehi S, Hosseinipour A, Sasanfar R, Eslami M. Gjb3 Gene Mutations in Non-Syndromic Hearing Loss of Bloch, Kurd, and Turkmen Ethnicities in Iran. IRANIAN JOURNAL OF PUBLIC HEALTH 2021; 49:2128-2135. [PMID: 33708733 PMCID: PMC7917519 DOI: 10.18502/ijph.v49i11.4730] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Background: Hearing loss (HL) is one of the most common heterogeneous congenital disabilities worldwide. Gap junction protein β-3 (GJB3) gene encodes Connexin31 protein (Cx31). The hereditary type of hearing impairment in this gene are known to cause both autosomal recessive and autosomal dominant form. In addition, GJB3 mutations have been involved in sensorineural deafness, erythrokeratodermia variabilis (EKV), and neuropathy diseases. We aimed to investigate GJB3 mutations in people suffering from HL among three different ethnicities of Iranian population (Baloch, Kurd, and Turkmen). Methods: In this descriptive study, 50 GJB2-negative non-syndromic hearing loss (NSHL) Iranian individuals from 3 ethnic groups of Baloch (n=17), Kurd (n =15) and Turkmen (n=18) were enrolled. DNA extractions, PCR, and mutation detection was carried out for the two large deletions of the GJB6, del (GJB6 -D13S1830,) and del (GJB6 -D13S1854) followed by direct DNA sequencing method for the GJB3. Results: DNA sequencing of GJB3 was shown a missense heterozygous mutation rs199689484 (NM_024009.3) GJB3: c.340G>A (p.Ala114Thr) in a Baloch patient, and a polymorphism rs35983826 (NM_024009.3) GJB3: c.798C>T (p.Asn266=) in a Turkman patient, in coding region of the GJB3. We did not detect del (GJB6 -D13S1830) and del (GJB6 -D13S1854) among these three ethnicities in Iran. Conclusion: Deafness is a heterogeneous disorder. Specific genes and mutations contribute to hearing loss that varies from locus to locus as well as from population to population.
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Affiliation(s)
- Farnoush Aliazami
- Department of Genetics, Tehran Medical Branch, Islamic Azad University, Tehran, Iran.,Applied Biotechnology Research Center, Tehran Medical Branch, Islamic Azad University, Tehran, Iran
| | - Dariush Farhud
- School of Public Health, Tehran University of Medical Sciences, Tehran, Iran.,Department of Basic Sciences, Iranian Academy of Medical Sciences, Tehran, Iran
| | - Marjan Zarif-Yeganeh
- Cellular and Molecular Endocrine Research Center, Research Institute for Endocrine Sciences, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Siamak Salehi
- Institute of Liver Studies, King's College Hospital, London, United Kingdom
| | - Azam Hosseinipour
- Department of Exceptional Children, Ministry of Education and Training of the Islamic Republic of Iran, Tehran, Iran
| | - Roxana Sasanfar
- Psychiatric and Neurodevelopmental Genetic Unit, Massachusetts General Hospital, Harvard Medical School, Boston, USA
| | - Maryam Eslami
- Department of Genetics, Tehran Medical Branch, Islamic Azad University, Tehran, Iran.,Applied Biotechnology Research Center, Tehran Medical Branch, Islamic Azad University, Tehran, Iran
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15
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Wang H, Gao Y, Guan J, Lan L, Yang J, Xiong W, Zhao C, Xie L, Yu L, Wang D, Wang Q. Phenotypic Heterogeneity of Post-lingual and/or Milder Hearing Loss for the Patients With the GJB2 c.235delC Homozygous Mutation. Front Cell Dev Biol 2021; 9:647240. [PMID: 33718389 PMCID: PMC7953049 DOI: 10.3389/fcell.2021.647240] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2020] [Accepted: 02/08/2021] [Indexed: 01/01/2023] Open
Abstract
Objective To report the phenotypic heterogeneity of GJB2 c.235delC homozygotes associated with post-lingual and/or milder hearing loss, and explore the possible mechanism of these unconditional phenotypes. Methods Mutation screening of GJB2 was performed on all ascertained members from Family 1006983 and three sporadic patients by polymerase chain reaction (PCR) amplification and Sanger sequencing. Next generation sequencing (NGS) was successively performed on some of the affected members and normal controls from Family 1006983 to explore additional possible genetic codes. Reverse transcriptase–quantitative PCR was conducted to test the expression of Connexin30. Results We identified a Chinese autosomal recessive hearing loss family with the GJB2 c.235delC homozygous mutation, affected members from which had post-lingual moderate to profound hearing impairment, and three sporadic patients with post-lingual moderate hearing impairment, instead of congenital profound hearing loss. NGS showed no other particular variants. Overexpression of Connexin30 in some of these cases was verified. Conclusion Post-lingual and/or moderate hearing impairment phenotypes of GJB2 c.235delC homozygotes are not the most common phenotype, revealing the heterogeneity of GJB2 pathogenic mutations. To determine the possible mechanism that rescues part of the hearing or postpones onset age of these cases, more cases are required to confirm both Connexin30 overexpression and the existence of modifier genes.
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Affiliation(s)
- Hongyang Wang
- College of Otolaryngology, Head and Neck Surgery, Chinese People's Liberation Army (PLA) Institute of Otolaryngology, Chinese People's Liberation Army (PLA) General Hospital, Beijing, China
| | - Yun Gao
- College of Otolaryngology, Head and Neck Surgery, Chinese People's Liberation Army (PLA) Institute of Otolaryngology, Chinese People's Liberation Army (PLA) General Hospital, Beijing, China.,National Clinical Research Center for Otolaryngologic Diseases, Beijing, China.,Key Lab of Hearing Impairment Science of Ministry of Education, Beijing, China.,Key Lab of Hearing Impairment Prevention and Treatment of Beijing, Beijing, China
| | - Jing Guan
- College of Otolaryngology, Head and Neck Surgery, Chinese People's Liberation Army (PLA) Institute of Otolaryngology, Chinese People's Liberation Army (PLA) General Hospital, Beijing, China.,National Clinical Research Center for Otolaryngologic Diseases, Beijing, China.,Key Lab of Hearing Impairment Science of Ministry of Education, Beijing, China.,Key Lab of Hearing Impairment Prevention and Treatment of Beijing, Beijing, China
| | - Lan Lan
- College of Otolaryngology, Head and Neck Surgery, Chinese People's Liberation Army (PLA) Institute of Otolaryngology, Chinese People's Liberation Army (PLA) General Hospital, Beijing, China.,National Clinical Research Center for Otolaryngologic Diseases, Beijing, China.,Key Lab of Hearing Impairment Science of Ministry of Education, Beijing, China.,Key Lab of Hearing Impairment Prevention and Treatment of Beijing, Beijing, China
| | - Ju Yang
- College of Otolaryngology, Head and Neck Surgery, Chinese People's Liberation Army (PLA) Institute of Otolaryngology, Chinese People's Liberation Army (PLA) General Hospital, Beijing, China.,National Clinical Research Center for Otolaryngologic Diseases, Beijing, China.,Key Lab of Hearing Impairment Science of Ministry of Education, Beijing, China.,Key Lab of Hearing Impairment Prevention and Treatment of Beijing, Beijing, China
| | - Wenping Xiong
- College of Otolaryngology, Head and Neck Surgery, Chinese People's Liberation Army (PLA) Institute of Otolaryngology, Chinese People's Liberation Army (PLA) General Hospital, Beijing, China.,National Clinical Research Center for Otolaryngologic Diseases, Beijing, China.,Key Lab of Hearing Impairment Science of Ministry of Education, Beijing, China.,Key Lab of Hearing Impairment Prevention and Treatment of Beijing, Beijing, China
| | - Cui Zhao
- College of Otolaryngology, Head and Neck Surgery, Chinese People's Liberation Army (PLA) Institute of Otolaryngology, Chinese People's Liberation Army (PLA) General Hospital, Beijing, China.,National Clinical Research Center for Otolaryngologic Diseases, Beijing, China.,Key Lab of Hearing Impairment Science of Ministry of Education, Beijing, China.,Key Lab of Hearing Impairment Prevention and Treatment of Beijing, Beijing, China
| | - Linyi Xie
- College of Otolaryngology, Head and Neck Surgery, Chinese People's Liberation Army (PLA) Institute of Otolaryngology, Chinese People's Liberation Army (PLA) General Hospital, Beijing, China.,National Clinical Research Center for Otolaryngologic Diseases, Beijing, China.,Key Lab of Hearing Impairment Science of Ministry of Education, Beijing, China.,Key Lab of Hearing Impairment Prevention and Treatment of Beijing, Beijing, China
| | - Lan Yu
- College of Otolaryngology, Head and Neck Surgery, Chinese People's Liberation Army (PLA) Institute of Otolaryngology, Chinese People's Liberation Army (PLA) General Hospital, Beijing, China.,National Clinical Research Center for Otolaryngologic Diseases, Beijing, China.,Key Lab of Hearing Impairment Science of Ministry of Education, Beijing, China.,Key Lab of Hearing Impairment Prevention and Treatment of Beijing, Beijing, China
| | - Dayong Wang
- College of Otolaryngology, Head and Neck Surgery, Chinese People's Liberation Army (PLA) Institute of Otolaryngology, Chinese People's Liberation Army (PLA) General Hospital, Beijing, China.,National Clinical Research Center for Otolaryngologic Diseases, Beijing, China.,Key Lab of Hearing Impairment Science of Ministry of Education, Beijing, China.,Key Lab of Hearing Impairment Prevention and Treatment of Beijing, Beijing, China
| | - Qiuju Wang
- College of Otolaryngology, Head and Neck Surgery, Chinese People's Liberation Army (PLA) Institute of Otolaryngology, Chinese People's Liberation Army (PLA) General Hospital, Beijing, China.,National Clinical Research Center for Otolaryngologic Diseases, Beijing, China.,Key Lab of Hearing Impairment Science of Ministry of Education, Beijing, China.,Key Lab of Hearing Impairment Prevention and Treatment of Beijing, Beijing, China
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Adadey SM, Wonkam-Tingang E, Twumasi Aboagye E, Nayo-Gyan DW, Boatemaa Ansong M, Quaye O, Awandare GA, Wonkam A. Connexin Genes Variants Associated with Non-Syndromic Hearing Impairment: A Systematic Review of the Global Burden. Life (Basel) 2020; 10:life10110258. [PMID: 33126609 PMCID: PMC7693846 DOI: 10.3390/life10110258] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2020] [Revised: 10/18/2020] [Accepted: 10/27/2020] [Indexed: 12/21/2022] Open
Abstract
Mutations in connexins are the most common causes of hearing impairment (HI) in many populations. Our aim was to review the global burden of pathogenic and likely pathogenic (PLP) variants in connexin genes associated with HI. We conducted a systematic review of the literature based on targeted inclusion/exclusion criteria of publications from 1997 to 2020. The databases used were PubMed, Scopus, Africa-Wide Information, and Web of Science. The protocol was registered on PROSPERO, the International Prospective Register of Systematic Reviews, with the registration number “CRD42020169697”. The data extracted were analyzed using Microsoft Excel and SPSS version 25 (IBM, Armonk, New York, United States). A total of 571 independent studies were retrieved and considered for data extraction with the majority of studies (47.8% (n = 289)) done in Asia. Targeted sequencing was found to be the most common technique used in investigating connexin gene mutations. We identified seven connexin genes that were associated with HI, and GJB2 (520/571 publications) was the most studied among the seven. Excluding PLP in GJB2, GJB6, and GJA1 the other connexin gene variants (thus GJB3, GJB4, GJC3, and GJC1 variants) had conflicting association with HI. Biallelic GJB2 PLP variants were the most common and widespread variants associated with non-syndromic hearing impairment (NSHI) in different global populations but absent in most African populations. The most common GJB2 alleles found to be predominant in specific populations include; p.Gly12ValfsTer2 in Europeans, North Africans, Brazilians, and Americans; p.V37I and p.L79Cfs in Asians; p.W24X in Indians; p.L56Rfs in Americans; and the founder mutation p.R143W in Africans from Ghana, or with putative Ghanaian ancestry. The present review suggests that only GJB2 and GJB3 are recognized and validated HI genes. The findings call for an extensive investigation of the other connexin genes in many populations to elucidate their contributions to HI, in order to improve gene-disease pair curations, globally.
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Affiliation(s)
- Samuel Mawuli Adadey
- West African Centre for Cell Biology of Infectious Pathogens (WACCBIP), University of Ghana, P.O. Box LG 54, Legon GA184, Accra, Greater Accra Region, Ghana; (S.M.A.); (O.Q.); (G.A.A.)
- Department of Biochemistry, Cell and Molecular Biology, University of Ghana, P.O. Box LG 54, Legon Accra GA184, Greater Accra Region, Ghana; (E.T.A.); (M.B.A.)
- Division of Human Genetics, Faculty of Health Sciences, University of Cape Town, Anzio Road, Observatory, Cape Town 7925, South Africa;
| | - Edmond Wonkam-Tingang
- Division of Human Genetics, Faculty of Health Sciences, University of Cape Town, Anzio Road, Observatory, Cape Town 7925, South Africa;
| | - Elvis Twumasi Aboagye
- Department of Biochemistry, Cell and Molecular Biology, University of Ghana, P.O. Box LG 54, Legon Accra GA184, Greater Accra Region, Ghana; (E.T.A.); (M.B.A.)
- Division of Human Genetics, Faculty of Health Sciences, University of Cape Town, Anzio Road, Observatory, Cape Town 7925, South Africa;
| | - Daniel Wonder Nayo-Gyan
- Department of Applied Chemistry and Biochemistry, C. K. Tedam University of Technology and Applied Sciences, P.O. Box 24, Navrongo 00000, Upper East Region, Ghana;
| | - Maame Boatemaa Ansong
- Department of Biochemistry, Cell and Molecular Biology, University of Ghana, P.O. Box LG 54, Legon Accra GA184, Greater Accra Region, Ghana; (E.T.A.); (M.B.A.)
| | - Osbourne Quaye
- West African Centre for Cell Biology of Infectious Pathogens (WACCBIP), University of Ghana, P.O. Box LG 54, Legon GA184, Accra, Greater Accra Region, Ghana; (S.M.A.); (O.Q.); (G.A.A.)
- Department of Biochemistry, Cell and Molecular Biology, University of Ghana, P.O. Box LG 54, Legon Accra GA184, Greater Accra Region, Ghana; (E.T.A.); (M.B.A.)
| | - Gordon A. Awandare
- West African Centre for Cell Biology of Infectious Pathogens (WACCBIP), University of Ghana, P.O. Box LG 54, Legon GA184, Accra, Greater Accra Region, Ghana; (S.M.A.); (O.Q.); (G.A.A.)
- Department of Biochemistry, Cell and Molecular Biology, University of Ghana, P.O. Box LG 54, Legon Accra GA184, Greater Accra Region, Ghana; (E.T.A.); (M.B.A.)
| | - Ambroise Wonkam
- Division of Human Genetics, Faculty of Health Sciences, University of Cape Town, Anzio Road, Observatory, Cape Town 7925, South Africa;
- Correspondence: ; Tel.: +27-21-4066307
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Wu K, Wang H, Guan J, Lan L, Zhao C, Zhang M, Wang D, Wang Q. A novel variant in diaphanous homolog 1 (DIAPH1) as the cause of auditory neuropathy in a Chinese family. Int J Pediatr Otorhinolaryngol 2020; 133:109947. [PMID: 32087478 DOI: 10.1016/j.ijporl.2020.109947] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/19/2019] [Revised: 02/11/2020] [Accepted: 02/11/2020] [Indexed: 11/30/2022]
Abstract
OBJECTIVES To determine the genetic cause of non-syndromic autosomal dominant deafness segregating in a Chinese Auditory neuropathy (AN) family. INTRODUCTION AN is a genetically related rare disease characterized by sensorineural hearing loss and retention of hair cell function. Diaphanous Homolog 1 (DIAPH1) is the causative gene of DFNA1. To date, no evidence has been detected to reveal the connection between gene DIAPH1 and AN. MATERIAL AND METHODS Audiological and imageological examinations, genome-wide linkage analysis, and whole exome sequencing (WES) were carried out on the family members. RESULTS In the 13-member branch of the family, 4 patients with preserved otoacoustic emission or cochlear microphonic and abnormal auditory brainstem responses were diagnosed with AN. Linkage analysis detected an interval with a LOD (log odds) score >4 on chr5:138.845-149.509 cM. Using WES we identified a novel frameshift variant c.3551_3552del (p.Glu1184AlafsTer11) in exon 26 of DIAPH1 located in the linkage region. The variant was co-segregated with hearing impairment phenotype in the family except 4 members below the average age of onset. We have found sufficient evidence conforming with the American College of Medical Genetics and Genomics Guideline to consider c.3551_3552del as the genetic cause of the family patients. CONCLUSION It is the first report to expand DIAPH1-related phenotypic spectrum to include AN. Our findings could facilitate the clinical diagnosis and genetic counselling for AN, especially for those with DIAPH1 variants.
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Affiliation(s)
- Kan Wu
- Department of Otolaryngology-Head and Neck Surgery, Chinese PLA Institute of Otolaryngology, Chinese PLA General Hospital, Beijing, 100853, China
| | - Hongyang Wang
- Department of Otolaryngology-Head and Neck Surgery, Chinese PLA Institute of Otolaryngology, Chinese PLA General Hospital, Beijing, 100853, China
| | - Jing Guan
- Department of Otolaryngology-Head and Neck Surgery, Chinese PLA Institute of Otolaryngology, Chinese PLA General Hospital, Beijing, 100853, China
| | - Lan Lan
- Department of Otolaryngology-Head and Neck Surgery, Chinese PLA Institute of Otolaryngology, Chinese PLA General Hospital, Beijing, 100853, China
| | - Cui Zhao
- Department of Otolaryngology-Head and Neck Surgery, Chinese PLA Institute of Otolaryngology, Chinese PLA General Hospital, Beijing, 100853, China
| | - Mengqian Zhang
- Department of Otolaryngology-Head and Neck Surgery, Chinese PLA Institute of Otolaryngology, Chinese PLA General Hospital, Beijing, 100853, China
| | - Dayong Wang
- Department of Otolaryngology-Head and Neck Surgery, Chinese PLA Institute of Otolaryngology, Chinese PLA General Hospital, Beijing, 100853, China.
| | - Qiuju Wang
- Department of Otolaryngology-Head and Neck Surgery, Chinese PLA Institute of Otolaryngology, Chinese PLA General Hospital, Beijing, 100853, China
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Yu X, Lin Y, Xu J, Che T, Li L, Yang T, Wu H. Molecular epidemiology of Chinese Han deaf patients with bi-allelic and mono-allelic GJB2 mutations. Orphanet J Rare Dis 2020; 15:29. [PMID: 31992338 PMCID: PMC6986010 DOI: 10.1186/s13023-020-1311-2] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2019] [Accepted: 01/17/2020] [Indexed: 02/07/2023] Open
Abstract
Background Recessive mutations in GJB2 is the most common cause of genetic hearing loss worldwide. The aim of this study is to determine the spectrum and frequency of GJB2 variants in Chinese Han deaf patients and to investigate the underlying causative genes in patients with mono-allelic GJB2 mutations. Methods We analyzed the mutation screening results of GJB2 in 1852 Chinese Han probands with apparently autosomal-recessive hearing loss in our laboratory. Targeted next-generation sequencing of 139 known deafness-related genes were performed in 44 probands with mono-allelic GJB2 mutations. Results Bi-allelic GJB2 mutations was identified in 25.65% of patients, in which the c.235delC (p.L79Cfs*3) mutation is the most frequent cause for both severe-to-profound (84.93%) and mild-to-moderate hearing loss (54.05%), while the c.109G > A (p.V37I) mutation is another frequent cause for mild-to-moderate hearing loss (40.54%). In 3.89% of patients only one mutant allele can be identified in GJB2. Targeted next generation sequencing in 44 such probands revealed digenic heterozygous mutations in GJB2/GJB6 and GJB2/GJB3 as the likely pathogenic mechanism in three probands. In 13 probands, on the other hand, pathogenic mutations in other deafness-associated genes (STRC, EYA1, MITF, PCDH15, USH2A, MYO15A, CDH23, OTOF, SLC26A4, SMPX, and TIMM8A) can be identified as the independent genetic cause, suggesting that the mono-allelic GJB2 mutations in those probands is likely co-incidental. Conclusions Our results demonstrated that GJB2 should be a primary target for mutation screening in Chinese Han deaf patients, and those with mono-allelic GJB2 mutations should be further screened by next generation sequencing.
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Affiliation(s)
- Xiaoyu Yu
- Department of Otorhinolaryngology-Head and Neck Surgery, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China.,Ear Institute, Shanghai Jiao Tong University School of Medicine, Shanghai, China.,Shanghai Key Laboratory of Translational Medicine on Ear and Nose Diseases, Shanghai, China
| | - Yun Lin
- Department of Otorhinolaryngology-Head and Neck Surgery, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China.,Ear Institute, Shanghai Jiao Tong University School of Medicine, Shanghai, China.,Shanghai Key Laboratory of Translational Medicine on Ear and Nose Diseases, Shanghai, China
| | - Jun Xu
- Department of Otorhinolaryngology-Head and Neck Surgery, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China.,Ear Institute, Shanghai Jiao Tong University School of Medicine, Shanghai, China.,Shanghai Key Laboratory of Translational Medicine on Ear and Nose Diseases, Shanghai, China
| | - Tuanjie Che
- Key Laboratory of Functional Genomic and Molecular Diagnosis of Gansu Province, Lanzhou, 730030, China
| | - Lin Li
- Laboratory of Precision Medicine and Translational Medicine, Suzhou Hospital Affiliated to Nanjing Medical University, Suzhou Science and Technology Town Hospital, Suzhou, 215153, China
| | - Tao Yang
- Department of Otorhinolaryngology-Head and Neck Surgery, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China. .,Ear Institute, Shanghai Jiao Tong University School of Medicine, Shanghai, China. .,Shanghai Key Laboratory of Translational Medicine on Ear and Nose Diseases, Shanghai, China.
| | - Hao Wu
- Department of Otorhinolaryngology-Head and Neck Surgery, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China. .,Ear Institute, Shanghai Jiao Tong University School of Medicine, Shanghai, China. .,Shanghai Key Laboratory of Translational Medicine on Ear and Nose Diseases, Shanghai, China.
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20
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Wu X, Zhang W, Li Y, Lin X. Structure and Function of Cochlear Gap Junctions and Implications for the Translation of Cochlear Gene Therapies. Front Cell Neurosci 2019; 13:529. [PMID: 31827424 PMCID: PMC6892400 DOI: 10.3389/fncel.2019.00529] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2019] [Accepted: 11/13/2019] [Indexed: 12/23/2022] Open
Abstract
Connexins (Cxs) are ubiquitous membrane proteins that are found throughout vertebrate organs, acting as building blocks of the gap junctions (GJs) known to play vital roles in the normal function of many organs. Mutations in Cx genes (particularly GJB2, which encodes Cx26) cause approximately half of all cases of congenital hearing loss in newborns. Great progress has been made in understanding GJ function and the molecular mechanisms for the role of Cxs in the cochlea. Data reveal that multiple types of Cxs work together to ensure normal development and function of the cochlea. These findings include many aspects not proposed in the classic K+ recycling theory, such as the formation of normal cochlear morphology (e.g., the opening of the tunnel of Corti), the fine-tuning of the innervation of nerve fibers to the hair cells (HCs), the maturation of the ribbon synapses, and the initiation of the endocochlear potential (EP). New data, especially those collected from targeted modification of major Cx genes in the mouse cochlea, have demonstrated that Cx26 plays an essential role in the postnatal maturation of the cochlea. Studies also show that Cx26 and Cx30 assume very different roles in the EP generation, given that only Cx26 is required for normal hearing. This article will review our current understanding of the molecular structure, cellular distribution, and major functions of cochlear GJs. Potential implications of the knowledge of cochlear GJs on the design and implementation of translational studies of cochlear gene therapies for Cx mutations are also discussed.
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Affiliation(s)
- Xuewen Wu
- Department of Otolaryngology, Head-Neck and Surgery, Xiangya Hospital of Central South University, Changsha, China
- Department of Otolaryngology, Emory University School of Medicine, Atlanta, GA, United States
| | - Wenjuan Zhang
- Department of Otolaryngology, Wuhan Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Yihui Li
- Department of Pharmacy, Changsha Hospital of Traditional Medicine, Changsha, China
| | - Xi Lin
- Department of Otolaryngology, Emory University School of Medicine, Atlanta, GA, United States
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21
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Comprehensive genetic testing of Chinese SNHL patients and variants interpretation using ACMG guidelines and ethnically matched normal controls. Eur J Hum Genet 2019; 28:231-243. [PMID: 31541171 PMCID: PMC6974605 DOI: 10.1038/s41431-019-0510-6] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2018] [Revised: 05/10/2019] [Accepted: 08/29/2019] [Indexed: 11/10/2022] Open
Abstract
Hereditary hearing loss is a monogenic disease with high genetic heterogeneity. Variants in more than 100 deafness genes underlie the basis of its pathogenesis. The aim of this study was to assess the ratio of SNVs in known deafness genes contributing to the etiology of both sporadic and familial sensorineural hearing loss patients from China. DNA samples from 1127 individuals, including normal hearing controls (n = 616), sporadic SNHL patients (n = 433), and deaf individuals (n = 78) from 30 hearing loss pedigrees were collected. The NGS tests included analysis of sequence alterations in 129 genes. The variants were interpreted according to the ACMG/AMP guidelines for genetic hearing loss combined with NGS data from 616 ethnically matched normal hearing adult controls. We identified a positive molecular diagnosis in 226 patients with sporadic SNHL (52.19%) and in patients from 17 deafness pedigrees (56.67%). Ethnically matched MAF filtering reduced the variants of unknown significance by 8.7%, from 6216 to 5675. Some complexities that may restrict causative variant identification are discussed. This report highlight the clinical utility of NGS panels identifying disease-causing variants for the diagnosis of hearing loss and underlines the importance of a broad data of control and ACMG/AMP standards for accurate clinical delineation of VUS variants.
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Mammano F. Inner Ear Connexin Channels: Roles in Development and Maintenance of Cochlear Function. Cold Spring Harb Perspect Med 2019; 9:a033233. [PMID: 30181354 PMCID: PMC6601451 DOI: 10.1101/cshperspect.a033233] [Citation(s) in RCA: 41] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Connexin 26 and connexin 30 are the prevailing isoforms in the epithelial and connective tissue gap junction systems of the developing and mature cochlea. The most frequently encountered variants of the genes that encode these connexins, which are transcriptionally coregulated, determine complete loss of protein function and are the predominant cause of prelingual hereditary deafness. Reducing connexin 26 expression by Cre/loxP recombination in the inner ear of adult mice results in a decreased endocochlear potential, increased hearing thresholds, and loss of >90% of outer hair cells, indicating that this connexin is essential for maintenance of cochlear function. In the developing cochlea, connexins are necessary for intercellular calcium signaling activity. Ribbon synapses and basolateral membrane currents fail to mature in inner hair cells of mice that are born with reduced connexin expression, even though hair cells do not express any connexin. In contrast, pannexin 1, an alternative mediator of intercellular signaling, is dispensable for hearing acquisition and auditory function.
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Affiliation(s)
- Fabio Mammano
- University of Padova, Department of Physics and Astronomy "G. Galilei," Padova 35129, Italy
- CNR Institute of Cell Biology and Neurobiology, Monterotondo 00015, Italy
- Shanghai Institute for Advanced Immunochemical Studies, ShanghaiTech University, Shanghai 201210, China
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Hernández-Guerra M, Hadjihambi A, Jalan R. Gap junctions in liver disease: Implications for pathogenesis and therapy. J Hepatol 2019; 70:759-772. [PMID: 30599172 DOI: 10.1016/j.jhep.2018.12.023] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/19/2018] [Revised: 12/03/2018] [Accepted: 12/12/2018] [Indexed: 02/07/2023]
Abstract
In the normal liver, cells interact closely through gap junctions. By providing a pathway for the trafficking of low molecular mass molecules, these channels contribute to tissue homeostasis and maintenance of hepatic function. Thus, dysfunction of gap junctions affects a wide variety of liver processes, such as differentiation, cell death, inflammation and fibrosis. In fact, dysfunctional gap junctions have been implicated, for more than a decade, in cholestatic disease, hepatic cancer and cirrhosis. Additionally, in recent years there is an increasing body of evidence that these channels are also involved in other relevant and prevalent liver pathological processes, such as non-alcoholic fatty liver disease, acute liver injury and portal hypertension. In parallel to these new clinical implications the available data include controversial observations. Thus, a comprehensive overview is required to better understand the functional complexity of these pores. This paper will review the most recent knowledge concerning gap junction dysfunction, with a special focus on the role of these channels in the pathogenesis of relevant clinical entities and on potential therapeutic targets that are amenable to modification by drugs.
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Affiliation(s)
| | | | - Rajiv Jalan
- UCL Institute for Liver and Digestive Health, Royal Free Medical School, London, UK
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Ming L, Wang Y, Lu W, Sun T. A Mutational Analysis of GJB2, SLC26A4, MT-RNA1, and GJB3 in Children with Nonsyndromic Hearing Loss in the Henan Province of China. Genet Test Mol Biomarkers 2018; 23:51-56. [PMID: 30589569 DOI: 10.1089/gtmb.2018.0146] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
BACKGROUND Hearing impairment is one of the most common neurosensory disorders afflicting humans. Approximately half of all cases have a genetic etiology. The distribution and frequency of genetic mutations that cause deafness differ significantly by ethnic group and geographic region. METHODS 130 sporadic nonsyndromic hearing loss (NSHL) children from the Henan province were subjected to microarray-based mutation detection. Nine pathogenic mutations were detected in four of the most common deafness-related genes (GJB2, GJB3, SLC26A4, and MT-RNA1). RESULTS Fifty percent of the analyzed patients (65/130) were shown to have genetic defects known to be related to deafness. Slightly >30% (41/130) had biallelic pathogenic mutations. One patient had pathogenic mutations in their mitochondrial genes (MT-RNA1); no mutations were detected in the GJB3 gene. Twenty-three (17.69%) patients were carriers of a single mutation in a recessive gene; these findings alone, however, cannot be interpreted as a cause of hearing loss. Utilizing this molecular strategy, we were able to arrive at a conclusive diagnosis for 42 of the NSHL children. CONCLUSION Genetic factors play a major role in sporadic NSHL patients from the Henan province, but it is clear that our screen needs to be expanded to include additional genes and alleles. Screening of potential pathogenic genes is important for patient risk assessment.
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Affiliation(s)
- Liang Ming
- 1 Key Clinical Laboratory of Henan Province, Department of Clinical Laboratory, The First Affiliated Hospital of Zhengzhou University , Zhengzhou, China
| | - Yangxia Wang
- 1 Key Clinical Laboratory of Henan Province, Department of Clinical Laboratory, The First Affiliated Hospital of Zhengzhou University , Zhengzhou, China
| | - Wei Lu
- 2 Department of Otology, The First Affiliated Hospital of Zhengzhou University , Zhengzhou, China
| | - Ting Sun
- 1 Key Clinical Laboratory of Henan Province, Department of Clinical Laboratory, The First Affiliated Hospital of Zhengzhou University , Zhengzhou, China
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Schrauwen I, Chakchouk I, Acharya A, Liaqat K, Irfanullah, Nickerson DA, Bamshad MJ, Shah K, Ahmad W, Leal SM. Novel digenic inheritance of PCDH15 and USH1G underlies profound non-syndromic hearing impairment. BMC MEDICAL GENETICS 2018; 19:122. [PMID: 30029624 PMCID: PMC6053831 DOI: 10.1186/s12881-018-0618-5] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/01/2018] [Accepted: 05/24/2018] [Indexed: 11/10/2022]
Abstract
BACKGROUND Digenic inheritance is the simplest model of oligenic disease. It can be observed when there is a strong epistatic interaction between two loci. For both syndromic and non-syndromic hearing impairment, several forms of digenic inheritance have been reported. METHODS We performed exome sequencing in a Pakistani family with profound non-syndromic hereditary hearing impairment to identify the genetic cause of disease. RESULTS We found that this family displays digenic inheritance for two trans heterozygous missense mutations, one in PCDH15 [p.(Arg1034His)] and another in USH1G [p.(Asp365Asn)]. Both of these genes are known to cause autosomal recessive non-syndromic hearing impairment and Usher syndrome. The protein products of PCDH15 and USH1G function together at the stereocilia tips in the hair cells and are necessary for proper mechanotransduction. Epistasis between Pcdh15 and Ush1G has been previously reported in digenic heterozygous mice. The digenic mice displayed a significant decrease in hearing compared to age-matched heterozygous animals. Until now no human examples have been reported. CONCLUSIONS The discovery of novel digenic inheritance mechanisms in hereditary hearing impairment will aid in understanding the interaction between defective proteins and further define inner ear function and its interactome.
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Affiliation(s)
- Isabelle Schrauwen
- Center for Statistical Genetics, Department of Molecular and Human Genetics, Baylor College of Medicine, One Baylor Plaza 700D, Houston, TX, 77030, USA
| | - Imen Chakchouk
- Center for Statistical Genetics, Department of Molecular and Human Genetics, Baylor College of Medicine, One Baylor Plaza 700D, Houston, TX, 77030, USA
| | - Anushree Acharya
- Center for Statistical Genetics, Department of Molecular and Human Genetics, Baylor College of Medicine, One Baylor Plaza 700D, Houston, TX, 77030, USA
| | - Khurram Liaqat
- Department of Biotechnology, Faculty of Biological Sciences, Quaid-i-Azam University, Islamabad, Pakistan
| | - Irfanullah
- Department of Biochemistry, Faculty of Biological Sciences, Quaid-i-Azam University, Islamabad, Pakistan
| | - Deborah A Nickerson
- Department of Genome Sciences, University of Washington, Seattle, Washington, USA
| | - Michael J Bamshad
- Department of Genome Sciences, University of Washington, Seattle, Washington, USA
- Department of Pediatrics, University of Washington, Seattle, Washington, USA
| | - Khadim Shah
- Department of Biochemistry, Faculty of Biological Sciences, Quaid-i-Azam University, Islamabad, Pakistan
| | - Wasim Ahmad
- Department of Biochemistry, Faculty of Biological Sciences, Quaid-i-Azam University, Islamabad, Pakistan
| | - Suzanne M Leal
- Center for Statistical Genetics, Department of Molecular and Human Genetics, Baylor College of Medicine, One Baylor Plaza 700D, Houston, TX, 77030, USA.
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Chen K, Wu X, Zong L, Jiang H. GJB3/GJB6 screening in GJB2 carriers with idiopathic hearing loss: Is it necessary? J Clin Lab Anal 2018; 32:e22592. [PMID: 29926981 DOI: 10.1002/jcla.22592] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2018] [Accepted: 05/29/2018] [Indexed: 11/07/2022] Open
Abstract
BACKGROUND Genetic analysis detected excessive mono-allelic recessive GJB2 mutations in individuals with idiopathic deafness; the remaining alleles in trans/cis are underdetermined. The aim of this study was to assess the contributions of variants in GJB3 or GJB6 to non-syndromic sensorineural hearing impairment (NSHI) in Chinese patients with mono-allelic GJB2 mutations. METHODS The entire coding sequences of GJB3/GJB6, as well as deletions in GJB6, in a cohort of NSHI patients (n = 100) carrying likely pathogenic heterozygous GJB2 mutations, were tested. Targeted next generation sequencing was further performed in a multiplex family GDHY with moderate to profound NSHI. RESULTS Putatively causative GJB3 variant underlied 1% (1/100) in this cohort. In family GDHY, we identified a rare GJB3 c.250G>A mutation, as double heterozygotes with GJB2 c.109G>A and/or a novel GJB2 mutation c.638T>C predicted to be damaging in a digenic inheritance after precluding other attributable mutations from 127 deafness genes. No GJB6 mutation was found. CONCLUSIONS GJB3/GJB6 variants account for a low proportion in autosomal recessive GJB2 mutation carriers in our cohort. Environmental causes, or other NSHI relevant genes, revealed by targeted next generation sequencing or whole exome sequencing, may play major roles in triggering deafness in these patients.
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Affiliation(s)
- Kaitian Chen
- Department of Otorhinolaryngology, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, China.,Institute of Otorhinolaryngology, Sun Yat-sen University, Guangzhou, China
| | - Xuan Wu
- Department of Otorhinolaryngology, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, China.,Institute of Otorhinolaryngology, Sun Yat-sen University, Guangzhou, China
| | - Ling Zong
- Department of Otorhinolaryngology, The Second Affiliated Hospital of Guangzhou Medical University, Guangzhou, China
| | - Hongyan Jiang
- Department of Otorhinolaryngology, Hainan General Hospital, Haikou, China
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NASERI M, AKBARZADEHLALEH M, MASOUDI M, AHANGARI N, POURSADEGH ZONOUZI AA, POURSADEGH ZONOUZI A, SHAMS L, NEJATIZADEH A. Genetic Linkage Analysis of DFNB4, DFNB28, DFNB93 Loci in Autosomal Recessive Non-syndromic Hearing Loss: Evidence for Digenic Inheritance in GJB2 and GJB3 Mutations. IRANIAN JOURNAL OF PUBLIC HEALTH 2018; 47:95-102. [PMID: 29318123 PMCID: PMC5756606] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
BACKGROUND Autosomal recessive non-syndromic hearing loss (ARNSHL) a most frequent hereditary type of hearing impairment, exhibit tremendous genetic heterogeneity. We aimed to determine the contribution of three common DFNB loci (DFNB4, DFNB28, and DFNB93), and mutation analysis of Gap Junction Beta-2 gene (GJB2) and GJB3 genes in ARNSHL subjects in southern Iran. METHODS Thirty-six large ARNSHL pedigrees (167 individuals) with at least two affected subjects (72 patients) were included in this descriptive study from Hormozgan Province of Iran, during 2014 - 2015. The variation of GJB2 and GJB3 genes were screened using direct sequencing method. The negative samples for GJB2 and GJB3 genes mutations were analyzed for the linkage to DFNB4, DFNB28, and DFNB93 loci by genotyping the corresponding short tandem repeat (STR) markers using polymerase chain reaction (PCR) and polyacrylamide gel electrophoresis (PAGE) methods. RESULTS DNA sequencing of GJB2 were identified heterozygous mutation (964 C/T) in 13.88% of the studied families. Three missense mutations (788G/A, 284C/T and 973G/C) were also detected in coding region of the GJB3 gene. The 284C/T mutation in the GJB3 occurs in compound heterozygosity along with the 964T/C mutation in the GJB2 in one family. Finally, we found no evidence of linkage to either of DFNB4, DFNB93 and DFNB28 loci. CONCLUSION Highlighting the hypothesis that a genetic interaction between GJB2 and GJB3 genes could be lead to ARNSHL, however, no evidence of linkage to the DFNB loci was found. 284C/T variant in GJB3 gene might be pathogenic when accompanied by variant in GJB2 in a digenic pattern. However, further large-scale familial and functional studies are required to challenge this hypothesis.
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Affiliation(s)
- Marzieh NASERI
- Molecular Medicine Research Center, Hormozgan University of Medical Sciences, Bandar Abbas, Iran
| | - Masoud AKBARZADEHLALEH
- Molecular Medicine Research Center, Hormozgan University of Medical Sciences, Bandar Abbas, Iran
| | - Marjan MASOUDI
- Molecular Medicine Research Center, Hormozgan University of Medical Sciences, Bandar Abbas, Iran
| | - Najmeh AHANGARI
- Molecular Medicine Research Center, Hormozgan University of Medical Sciences, Bandar Abbas, Iran
| | | | | | - Leila SHAMS
- Molecular Medicine Research Center, Hormozgan University of Medical Sciences, Bandar Abbas, Iran
| | - Azim NEJATIZADEH
- Molecular Medicine Research Center, Hormozgan University of Medical Sciences, Bandar Abbas, Iran,Corresponding Author:
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Huang S, Huang B, Wang G, Kang DY, Zhang X, Meng X, Dai P. The relationship between the GJB3 c.538C>T variant and hearing phenotype in the Chinese population. Int J Pediatr Otorhinolaryngol 2017; 102:67-70. [PMID: 29106878 DOI: 10.1016/j.ijporl.2017.09.001] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/24/2017] [Revised: 08/31/2017] [Accepted: 09/02/2017] [Indexed: 10/18/2022]
Abstract
BACKGROUND Mutations in GJB3 were originally shown to underlie an autosomal dominant form of non-syndromic deafness in Chinese patients and the c.538C>T (p.R180*) variants caused high-frequency hearing loss. But after that, few reports have reported this mutation. This study investigated the relationship between the GJB3 c.538C>T variant and hearing phenotype in Chinese to assist with risk assessment and genetic counseling for hearing loss patients and their families. METHOD The study enrolled 5700 patients with hearing loss and 4600 normal subjects. Deafness gene mutations were distinguished using a gene chip. The GJB3 c.538C>T variant rate was calculated from the results. RESULT Of the 5700 patients, 23 (0.40%) carried a GJB3 c.538C>T heterozygous variant; of these, 11 patients had other gene (GJB2/SLC26A4) mutations simultaneously. Most patients had moderate to profound hearing loss. All 23 patients were sporadic cases and had no family history of deafness. Of the 4600 normal individuals, 11 (0.24%) had GJB3 c.538C>T heterozygous variant. There was no statistical difference in incidence between the two groups. CONCLUSIONS Our results showed that the GJB3 c.538C>T variant has a very low incidence in the Chinese population, and there was no clear evidence to support a role of the GJB3 c.538C>T variant in the autosomal dominant form of non-syndromic deafness. Our findings suggested that GJB3 c.538C>T does not contribute to hearing loss, and this conclusion will assist with genetic counseling and risk prediction for deafness related to the GJB3 c.538C>T variant.
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Affiliation(s)
- Shasha Huang
- Department of Otolaryngology, PLA General Hospital, Do.28 Fuxing Road, Beijing 100853, People's Republic of China
| | - Bangqing Huang
- Department of Otolaryngology, Hainan Branch of PLA General Hospital, Haitang Bay, Sanya 572000, People's Republic of China
| | - Guojian Wang
- Department of Otolaryngology, PLA General Hospital, Do.28 Fuxing Road, Beijing 100853, People's Republic of China
| | - Dong Yang Kang
- Department of Otolaryngology, PLA General Hospital, Do.28 Fuxing Road, Beijing 100853, People's Republic of China
| | - Xin Zhang
- Department of Otolaryngology, PLA General Hospital, Do.28 Fuxing Road, Beijing 100853, People's Republic of China
| | - Xiaoxiao Meng
- Department of Otolaryngology, PLA General Hospital, Do.28 Fuxing Road, Beijing 100853, People's Republic of China
| | - Pu Dai
- Department of Otolaryngology, PLA General Hospital, Do.28 Fuxing Road, Beijing 100853, People's Republic of China.
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Sampaio‐Silva J, Batissoco AC, Jesus‐Santos R, Abath‐Neto O, Scarpelli LC, Nishimura PY, Galindo LT, Bento RF, Oiticica J, Lezirovitz K. Exome Sequencing Identifies a Novel Nonsense Mutation of
MYO6
as the Cause of Deafness in a Brazilian Family. Ann Hum Genet 2017; 82:23-34. [DOI: 10.1111/ahg.12213] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2017] [Accepted: 08/16/2017] [Indexed: 02/04/2023]
Affiliation(s)
- Juliana Sampaio‐Silva
- Laboratório de Otorrinolaringologia/LIM32 Hospital das Clinicas HCFMUSP Faculdade de Medicina Universidade de Sao Paulo Sao Paulo SP Brasil
| | - Ana Carla Batissoco
- Laboratório de Otorrinolaringologia/LIM32 Hospital das Clinicas HCFMUSP Faculdade de Medicina Universidade de Sao Paulo Sao Paulo SP Brasil
| | - Rafaela Jesus‐Santos
- Laboratório de Otorrinolaringologia/LIM32 Hospital das Clinicas HCFMUSP Faculdade de Medicina Universidade de Sao Paulo Sao Paulo SP Brasil
| | - Osório Abath‐Neto
- Departamento de Neurologia Faculdade de Medicina FMUSP Universidade de Sao Paulo Sao Paulo SP Brasil
| | | | | | - Layla Testa Galindo
- Setor de Biologia Molecular Grupo DASA – Diagnósticos da América Barueri SP Brasil
| | - Ricardo Ferreira Bento
- Laboratório de Otorrinolaringologia/LIM32 Hospital das Clinicas HCFMUSP Faculdade de Medicina Universidade de Sao Paulo Sao Paulo SP Brasil
| | - Jeanne Oiticica
- Laboratório de Otorrinolaringologia/LIM32 Hospital das Clinicas HCFMUSP Faculdade de Medicina Universidade de Sao Paulo Sao Paulo SP Brasil
| | - Karina Lezirovitz
- Laboratório de Otorrinolaringologia/LIM32 Hospital das Clinicas HCFMUSP Faculdade de Medicina Universidade de Sao Paulo Sao Paulo SP Brasil
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Pshennikova VG, Barashkov NA, Solovyev AV, Romanov GP, Diakonov EE, Sazonov NN, Morozov IV, Bondar AA, Posukh OL, Dzhemileva LU, Khusnutdinova EK, Tomsky MI, Fedorova SA. Analysis of GJB6 (Сx30) and GJB3 (Сx31) genes in deaf patients with monoallelic mutations in GJB2 (Сx26) gene in the Sakha Republic (Yakutia). RUSS J GENET+ 2017. [DOI: 10.1134/s1022795417030103] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Srinivas M, Verselis VK, White TW. Human diseases associated with connexin mutations. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2017; 1860:192-201. [PMID: 28457858 DOI: 10.1016/j.bbamem.2017.04.024] [Citation(s) in RCA: 98] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/27/2017] [Revised: 04/20/2017] [Accepted: 04/25/2017] [Indexed: 01/11/2023]
Abstract
Gap junctions and hemichannels comprised of connexins impact many cellular processes. Significant advances in our understanding of the functional role of these channels have been made by the identification of a host of genetic diseases caused by connexin mutations. Prominent features of connexin disorders are the inability of other connexins expressed in the same cell type to compensate for the mutated one, and the ability of connexin mutants to dominantly influence the activity of other wild-type connexins. Functional studies have begun to identify some of the underlying mechanisms whereby connexin channel mutation contributes to the disease state. Detailed mechanistic understanding of these functional differences will help to facilitate new pathophysiology driven therapies for the diverse array of connexin genetic disorders. This article is part of a Special Issue entitled: Gap Junction Proteins edited by Jean Claude Herve.
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Affiliation(s)
- Miduturu Srinivas
- Department of Biological and Vision Sciences, SUNY College of Optometry, New York, NY 10036, USA
| | - Vytas K Verselis
- Dominick P. Purpura Department of Neuroscience, Albert Einstein College of Medicine, Bronx, NY 10461, USA
| | - Thomas W White
- Department of Physiology and Biophysics, Stony Brook University, Stony Brook, NY 11794, USA.
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LI YUNLONG, ZHU BAOSHENG. Genotypes and phenotypes of a family with a deaf child carrying combined heterozygous mutations in SLC26A4 and GJB3 genes. Mol Med Rep 2016; 14:319-24. [DOI: 10.3892/mmr.2016.5280] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2015] [Accepted: 03/29/2016] [Indexed: 11/06/2022] Open
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Kim SY, Kim AR, Kim NKD, Lee C, Kim MY, Jeon EH, Park WY, Choi BY. Unraveling of Enigmatic Hearing-Impaired GJB2 Single Heterozygotes by Massive Parallel Sequencing: DFNB1 or Not? Medicine (Baltimore) 2016; 95:e3029. [PMID: 27057829 PMCID: PMC4998745 DOI: 10.1097/md.0000000000003029] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
The molecular etiology of nonsyndromic sensorineural hearing loss (SNHL) in subjects with only one detectable autosomal recessive GJB2 mutation is unclear. Here, we report GJB2 single heterozygotes with various final genetic diagnoses and suggest appropriate diagnostic strategies. A total of 160 subjects with SNHL without phenotypic markers were screened for GJB2 mutations. Single-nucleotide variants or structural variations within the DFNB1 locus or in other deafness genes were examined by Sanger sequencing, breakpoint PCR, and targeted exome sequencing (TES) of 129 deafness genes. We identified 27 subjects with two mutations and 10 subjects with only one detectable mutation in GJB2. The detection rate of the single GJB2 mutation among the 160 SNHL subjects in the present study (6.25%) was higher than 2.58% in normal hearing controls in Korean. The DFNB1 was clearly excluded as a molecular etiology in four (40%) subjects: other recessive deafness genes (N = 3) accounted for SNHL and the causative gene for the other non-DFNB1 subject (N = 1) was not identified. The etiology of additional two subjects was potentially explained by digenic etiology (N = 2) of GJB2 with MITF and GJB3, respectively. The contribution of the single GJB2 mutation in the four remaining subjects is unclear. Comprehensive diagnostic testing including TES is prerequisite for understanding GJB2 single heterozygotes.
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Affiliation(s)
- So Young Kim
- From the Department of Otorhinolaryngology-Head and Neck Surgery, CHA medical center, CHA university, Seongnam (SYK), Department of Otorhinolaryngology-Head and Neck Surgery (SYK, ARK), Seoul National University Hospital, Seoul National University College of Medicine; Samsung Genome Institue (NKDK, CL), Samsung Medical Center, Seoul, Korea; Department of Health Sciences and Technology (CL), SAIHST, Sungkyunkwan University, Seobu-ro, Jangan-gu, Suwon, Republic of Korea; Department of Otorhinolaryngology-Head and Neck Surgery (MYK, E-HJ, BYC), Seoul National University Bundang Hospital, Seoul National University College of Medicine, Seongnam; Samsung Genome Institute (W-YP), Samsung Medical Center; Department of Molecular Cell Biology, School of Medicine (W-YP), Sungkyunkwan University; Sensory Organ Research Institute (BYC), Seoul National University Medical Research Center, Seoul, Korea; and Wide River Institute of Immunology (BYC), Seoul National University College of Medicine, Hongcheon, Republic of Korea
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Miyasaka Y, Shitara H, Suzuki S, Yoshimoto S, Seki Y, Ohshiba Y, Okumura K, Taya C, Tokano H, Kitamura K, Takada T, Hibino H, Shiroishi T, Kominami R, Yonekawa H, Kikkawa Y. Heterozygous mutation of Ush1g/Sans in mice causes early-onset progressive hearing loss, which is recovered by reconstituting the strain-specific mutation in Cdh23. Hum Mol Genet 2016; 25:2045-2059. [PMID: 26936824 DOI: 10.1093/hmg/ddw078] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2015] [Accepted: 02/29/2016] [Indexed: 12/21/2022] Open
Abstract
Most clinical reports have suggested that patients with congenital profound hearing loss have recessive mutations in deafness genes, whereas dominant alleles are associated with progressive hearing loss (PHL). Jackson shaker (Ush1gjs) is a mouse model of recessive deafness that exhibits congenital profound deafness caused by the homozygous mutation of Ush1g/Sans on chromosome 11. We found that C57BL/6J-Ush1gjs/+ heterozygous mice exhibited early-onset PHL (ePHL) accompanied by progressive degeneration of stereocilia in the cochlear outer hair cells. Interestingly, ePHL did not develop in mutant mice with the C3H/HeN background, thus suggesting that other genetic factors are required for ePHL development. Therefore, we performed classical genetic analyses and found that the occurrence of ePHL in Ush1gjs/+ mice was associated with an interval in chromosome 10 that contains the cadherin 23 gene (Cdh23), which is also responsible for human deafness. To confirm this mutation effect, we generated C57BL/6J-Ush1gjs/+, Cdh23c.753A/G double-heterozygous mice by using the CRISPR/Cas9-mediated Cdh23c.753A>G knock-in method. The Cdh23c.753A/G mice harbored a one-base substitution (A for G), and the homozygous A allele caused moderate hearing loss with aging. Analyses revealed the complete recovery of ePHL and stereocilia degeneration in C57BL/6J-Ush1gjs/+ mice. These results clearly show that the development of ePHL requires at least two mutant alleles of the Ush1g and Cdh23 genes. Our results also suggest that because the SANS and CDH23 proteins form a complex in the stereocilia, the interaction between these proteins may play key roles in the maintenance of stereocilia and the prevention of ePHL.
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Affiliation(s)
- Yuki Miyasaka
- Mammalian Genetics Project, Graduate School of Medical and Dental Sciences
| | - Hiroshi Shitara
- Laboratory for Transgenic Technology, Tokyo Metropolitan Institute of Medical Science, Tokyo 156-8506, Japan, Graduate School of Life and Environmental Sciences, University of Tsukuba, Tsukuba 305-8572, Japan
| | | | - Sachi Yoshimoto
- Laboratory for Transgenic Technology, Tokyo Metropolitan Institute of Medical Science, Tokyo 156-8506, Japan, Graduate School of Life and Environmental Sciences, University of Tsukuba, Tsukuba 305-8572, Japan
| | | | - Yasuhiro Ohshiba
- Mammalian Genetics Project, Graduate School of Medical and Dental Sciences
| | - Kazuhiro Okumura
- Division of Oncogenomics, Cancer Genome Center, Chiba Cancer Center Research Institute, Chiba 260-0801, Japan
| | - Choji Taya
- Laboratory for Transgenic Technology, Tokyo Metropolitan Institute of Medical Science, Tokyo 156-8506, Japan
| | - Hisashi Tokano
- Department of Otolaryngology, Tokyo Medical and Dental University, Tokyo 113-0034, Japan and
| | - Ken Kitamura
- Department of Otolaryngology, Tokyo Medical and Dental University, Tokyo 113-0034, Japan and
| | - Toyoyuki Takada
- Mammalian Genetics Laboratory, National Institute of Genetics, Mishima 411-8540, Japan
| | - Hiroshi Hibino
- Department of Molecular Physiology, Niigata University School of Medicine, Niigata 951-8510, Japan
| | - Toshihiko Shiroishi
- Mammalian Genetics Laboratory, National Institute of Genetics, Mishima 411-8540, Japan
| | | | - Hiromichi Yonekawa
- Laboratory for Transgenic Technology, Tokyo Metropolitan Institute of Medical Science, Tokyo 156-8506, Japan
| | - Yoshiaki Kikkawa
- Mammalian Genetics Project, Graduate School of Medical and Dental Sciences,
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Yuan Y, Gao X, Huang B, Lu J, Wang G, Lin X, Qu Y, Dai P. Phenotypic Heterogeneity in a DFNA20/26 family segregating a novel ACTG1 mutation. BMC Genet 2016; 17:33. [PMID: 26832775 PMCID: PMC4736096 DOI: 10.1186/s12863-016-0333-1] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2015] [Accepted: 01/14/2016] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Genetic factors play an important role in hearing loss, contributing to approximately 60% of cases of congenital hearing loss. Autosomal dominant deafness accounts for approximately 20% of cases of hereditary hearing loss. Diseases with autosomal dominant inheritance often show pleiotropy, different degrees of penetrance, and variable expressivity. METHODS A three-generation Chinese family with autosomal dominant nonsyndromic hearing impairment (ADNSHI) was enrolled in this study. Audiometric data and blood samples were collected from the family. In total, 129 known human deafness genes were sequenced using next-generation sequencing (NGS) to identify the responsible gene mutation in the family. Whole Exome Sequencing (WES) was performed to exclude any other variant that cosegregated with the phenotype. RESULTS The age of onset of the affected family members was the second decade of life. The condition began with high-frequency hearing impairment in all family members excluding III:2. The novel ACTG1 c.638A > G (p.K213R) mutation was found in all affected family members and was not found in the unaffected family members. A heterozygous c.638A > G mutation in ACTG1 and homozygous c.109G > A (p.V37I) mutation in GJB2 were found in III:2, who was born with hearing loss. The WES result concurred with that of targeted sequencing of known deafness genes. CONCLUSIONS The novel mutation p.K213R in ACTG1 was found to be co-segregated with hearing loss and the genetic cause of ADNSHI in this family. A homozygous mutation associated with recessive inheritance only rarely co-acts with a dominant mutation to result in hearing loss in a dominant family. In such cases, the mutations in the two genes, as in ACTG1 and GJB2 in the present study, may result in a more severe phenotype. Targeted sequencing of known deafness genes is one of the best choices to identify the genetic cause in hereditary hearing loss families.
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Affiliation(s)
- Yongyi Yuan
- Department of Otolaryngology, Chinese PLA General Hospital, Beijing, 100853, People's Republic of China. .,Department of Otolaryngology, Hainan Branch of PLA General Hospital, Sanya, 572000, People's Republic of China.
| | - Xue Gao
- Department of Otolaryngology, Chinese PLA General Hospital, Beijing, 100853, People's Republic of China.
| | - Bangqing Huang
- Department of Otolaryngology, Hainan Branch of PLA General Hospital, Sanya, 572000, People's Republic of China.
| | - Jingqiao Lu
- Department of Otolaryngology, Emory University School of Medicine, Atlanta, GA, 30322-3030, USA.
| | - Guojian Wang
- Department of Otolaryngology, Chinese PLA General Hospital, Beijing, 100853, People's Republic of China.
| | - Xi Lin
- Department of Otolaryngology, Emory University School of Medicine, Atlanta, GA, 30322-3030, USA.
| | - Yan Qu
- Third hospital of Hebei Medical University, Shijiazhuang, Hebei Province, 050051, People's Republic of China.
| | - Pu Dai
- Department of Otolaryngology, Chinese PLA General Hospital, Beijing, 100853, People's Republic of China.
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Abou Tayoun AN, Al Turki SH, Oza AM, Bowser MJ, Hernandez AL, Funke BH, Rehm HL, Amr SS. Improving hearing loss gene testing: a systematic review of gene evidence toward more efficient next-generation sequencing-based diagnostic testing and interpretation. Genet Med 2015; 18:545-53. [PMID: 26562227 DOI: 10.1038/gim.2015.141] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2015] [Accepted: 08/27/2015] [Indexed: 12/11/2022] Open
Abstract
PURPOSE With next generation sequencing technology improvement and cost reductions, it has become technically feasible to sequence a large number of genes in one diagnostic test. This is especially relevant for diseases with large genetic and/or phenotypic heterogeneity, such as hearing loss. However, variant interpretation remains the major bottleneck. This is further exacerbated by the lack in the clinical genetics community of consensus criteria for defining the evidence necessary to include genes on targeted disease panels or in genomic reports, and the consequent risk of reporting variants in genes with no relevance to disease. METHODS We describe a systematic evidence-based approach for assessing gene-disease associations and for curating relevant genes for different disease aspects, including mode of inheritance, phenotypic severity, and mutation spectrum. RESULTS By applying this approach to clinically available hearing loss gene panels with a total of 163 genes, we show that a significant number (45%) of genes lack sufficient evidence of association with disease and thus are expected to increase uncertainty and patient anxiety, in addition to intensifying the interpretation burden. Information about all curated genes is summarized. Our retrospective analysis of 539 hearing loss cases tested by our previous OtoGenomeV2 panel demonstrates the impact of including genes with weak disease association in laboratory wet-bench and interpretation processes. CONCLUSION Our study is, to our knowledge, the first to highlight the urgent need for defining the clinical validity of gene-disease relationships for more efficient and accurate clinical testing and reporting.Genet Med 18 6, 545-553.
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Affiliation(s)
- Ahmad N Abou Tayoun
- Genetics Training Program, Harvard Medical School, Cambridge, Massachusetts, USA.,Laboratory for Molecular Medicine, Partners Healthcare Personalized Medicine, Cambridge, Massachusetts, USA.,Division of Genomic Diagnostics, The Children's Hospital of Philadelphia, The University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania, USA
| | - Saeed H Al Turki
- Genetics Training Program, Harvard Medical School, Cambridge, Massachusetts, USA
| | - Andrea M Oza
- Laboratory for Molecular Medicine, Partners Healthcare Personalized Medicine, Cambridge, Massachusetts, USA
| | - Mark J Bowser
- Laboratory for Molecular Medicine, Partners Healthcare Personalized Medicine, Cambridge, Massachusetts, USA
| | - Amy L Hernandez
- Laboratory for Molecular Medicine, Partners Healthcare Personalized Medicine, Cambridge, Massachusetts, USA
| | - Birgit H Funke
- Laboratory for Molecular Medicine, Partners Healthcare Personalized Medicine, Cambridge, Massachusetts, USA.,Department of Pathology, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - Heidi L Rehm
- Laboratory for Molecular Medicine, Partners Healthcare Personalized Medicine, Cambridge, Massachusetts, USA.,Department of Pathology, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - Sami S Amr
- Laboratory for Molecular Medicine, Partners Healthcare Personalized Medicine, Cambridge, Massachusetts, USA.,Department of Pathology, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts, USA
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Tang C, Chen X, Chi J, Yang D, Liu S, Liu M, Pan Q, Fan J, Wang D, Zhang Z. Pathogenic Cx31 is un/misfolded to cause skin abnormality via a Fos/JunB-mediated mechanism. Hum Mol Genet 2015; 24:6054-65. [DOI: 10.1093/hmg/ddv317] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2015] [Accepted: 07/31/2015] [Indexed: 01/29/2023] Open
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Peguero B, Tempel BL. A Chromosome 17 Locus Engenders Frequency-Specific Non-Progressive Hearing Loss that Contributes to Age-Related Hearing Loss in Mice. J Assoc Res Otolaryngol 2015; 16:459-71. [PMID: 25940139 DOI: 10.1007/s10162-015-0519-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2014] [Accepted: 04/16/2015] [Indexed: 12/20/2022] Open
Abstract
The 129S6/SvEvTac (129S6) inbred mouse is known for its resistance to noise-induced hearing loss (NIHL). However, less is understood of its unique age-related hearing loss (AHL) phenotype and its potential relationship with the resistance to NIHL. Here, we studied the physiological characteristics of hearing loss in 129S6 and asked if noise resistance (NR) and AHL are genetically linked to the same chromosomal region. We used auditory brainstem response (ABR) and distortion product otoacoustic emissions (DPOAE) to examine hearing sensitivity between 1 and 13 months of age of recombinant-inbred (congenic) mice with an NR phenotype. We identified a region of proximal chromosome (Chr) 17 (D17Mit143-D17Mit100) that contributes to a sensory, non-progressive hearing loss (NPHL) affecting exclusively the high-frequencies (>24 kHz) and maps to the nr1 locus on Chr 17. ABR experiments showed that 129S6 and CBA/CaJ F1 (CBACa) hybrid mice exhibit normal hearing, indicating that the hearing loss in 129S6 mice is inherited recessively. An allelic complementation test between the 129S6 and 101/H (101H) strains did not rescue hearing loss, suggesting genetic allelism between the nphl and phl1 loci of these strains, respectively. The hybrids had a milder hearing loss than either parental strain, which indicate a possible interaction with other genes in the mouse background or a digenic interaction between different genes that reside in the same genomic region. Our study defines a locus for nphl on Chr 17 affecting frequencies greater than 24 kHz.
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Affiliation(s)
- Braulio Peguero
- The Virginia Merrill Bloedel Hearing Research Center, University of Washington, Box 357923, Seattle, WA, 98195, USA
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Vona B, Nanda I, Hofrichter MAH, Shehata-Dieler W, Haaf T. Non-syndromic hearing loss gene identification: A brief history and glimpse into the future. Mol Cell Probes 2015; 29:260-70. [PMID: 25845345 DOI: 10.1016/j.mcp.2015.03.008] [Citation(s) in RCA: 63] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2015] [Revised: 03/19/2015] [Accepted: 03/23/2015] [Indexed: 11/27/2022]
Abstract
From the first identified non-syndromic hearing loss gene in 1995, to those discovered in present day, the field of human genetics has witnessed an unparalleled revolution that includes the completion of the Human Genome Project in 2003 to the $1000 genome in 2014. This review highlights the classical and cutting-edge strategies for non-syndromic hearing loss gene identification that have been used throughout the twenty year history with a special emphasis on how the innovative breakthroughs in next generation sequencing technology have forever changed candidate gene approaches. The simplified approach afforded by next generation sequencing technology provides a second chance for the many linked loci in large and well characterized families that have been identified by linkage analysis but have presently failed to identify a causative gene. It also discusses some complexities that may restrict eventual candidate gene discovery and calls for novel approaches to answer some of the questions that make this simple Mendelian disorder so intriguing.
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Affiliation(s)
- Barbara Vona
- Institute of Human Genetics, Julius Maximilians University, Würzburg, Germany.
| | - Indrajit Nanda
- Institute of Human Genetics, Julius Maximilians University, Würzburg, Germany
| | | | - Wafaa Shehata-Dieler
- Comprehensive Hearing Center, Department of Otorhinolaryngology, Plastic, Aesthetic and Reconstructive Surgery, University Hospital, Würzburg, Germany
| | - Thomas Haaf
- Institute of Human Genetics, Julius Maximilians University, Würzburg, Germany
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Government-funded universal newborn hearing screening and genetic analyses of deafness predisposing genes in Taiwan. Int J Pediatr Otorhinolaryngol 2015; 79:584-90. [PMID: 25724631 DOI: 10.1016/j.ijporl.2015.01.033] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/29/2014] [Revised: 01/09/2015] [Accepted: 01/31/2015] [Indexed: 11/20/2022]
Abstract
OBJECTIVE To investigate the association of eight connexin genes (GJB2, GJB4, GJA1P1, GJB6, GJB3, GJA1, GJB1, and GJC3) and the SLC26A4 gene with congenital hearing impairment among infants in a universal newborn hearing screening program. METHOD From September 2009 to October 2013, the consecutive neonates born in all six branches of Taipei City Hospital were enrolled. Infants who failed the newborn hearing screening and were diagnosed with hearing impairment underwent the genetic analyses. RESULT 15,404 neonates were born at Taipei City Hospital, and 15,345 neonates underwent newborn hearing screening. Among them, 32 infants were diagnosed with unilateral or bilateral hearing impairment. 26 of them underwent analyses of the connexin genes and the SLC26A4 gene. Of the connexin genes, two infants carried a GJB3 mutation (heterozygous c.580G>A and heterozygous c.520G>A, respectively). Only one infant carried a GJB2 mutation (homozygous c.235delC). One infant carried a GJA1P1 mutation (heterozygous c.929delC) and another carried a GJB4 mutation (heterozygous c.302G>A). Additionally, one infant carried a GJA1P1 novel variant (heterozygous c.1081C>T). Another infant carried a GJA1 novel variant (heterozygous c.1-33C>G). Of the SLC26A4 gene, one infant carried heterozygous c.919-2A>G mutation and a novel variant (heterozygous c.164+1G>C), and high-resolution computed tomography (HRCT) of the temporal bone revealed bilateral enlarged vestibular aqueducts. One infant carried heterozygous c.919-2A>G mutation and no inner ear anomalies were demonstrated by HRCT of the temporal bone. Another infant carried a novel variant (heterozygous c.818C>T). CONCLUSION These results provide a genetic profile of the connexin genes and SLC26A4 gene among infants with hearing impairment detected by a universal newborn hearing screening program in Taiwan. Further studies and long-term follow up of this cohort are warranted to determine the pathogenicity of each variants and the long-term hearing consequence.
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Mencarelli MA, Heidet L, Storey H, van Geel M, Knebelmann B, Fallerini C, Miglietti N, Antonucci MF, Cetta F, Sayer JA, van den Wijngaard A, Yau S, Mari F, Bruttini M, Ariani F, Dahan K, Smeets B, Antignac C, Flinter F, Renieri A. Evidence of digenic inheritance in Alport syndrome. J Med Genet 2015; 52:163-74. [PMID: 25575550 DOI: 10.1136/jmedgenet-2014-102822] [Citation(s) in RCA: 110] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
BACKGROUND Alport syndrome is a clinically heterogeneous, progressive nephropathy caused by mutations in collagen IV genes, namely COL4A3 and COL4A4 on chromosome 2 and COL4A5 on chromosome X. The wide phenotypic variability and the presence of incomplete penetrance suggest that a simple Mendelian model cannot completely explain the genetic control of this disease. Therefore, we explored the possibility that Alport syndrome is under digenic control. METHODS Using massively parallel sequencing, we identified 11 patients who had pathogenic mutations in two collagen IV genes. For each proband, we ascertained the presence of the same mutations in up to 12 members of the extended family for a total of 56 persons studied. RESULTS Overall, 23 mutations were found. Individuals with two pathogenic mutations in different genes had a mean age of renal function deterioration intermediate with respect to the autosomal-dominant form and the autosomal-recessive one, in line with molecule stoichiometry of the disruption of the type IV collagen triple helix. CONCLUSIONS Segregation analysis indicated three possible digenic segregation models: (i) autosomal inheritance with mutations on different chromosomes, resembling recessive inheritance (five families); (ii) autosomal inheritance with mutations on the same chromosome resembling dominant inheritance (two families) and (iii) unlinked autosomal and X-linked inheritance having a peculiar segregation (four families). This pedigree analysis provides evidence for digenic inheritance of Alport syndrome. Clinical geneticists and nephrologists should be aware of this possibility in order to more accurately assess inheritance probabilities, predict prognosis and identify other family members at risk.
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Affiliation(s)
- Maria Antonietta Mencarelli
- Medical Genetics, University of Siena, Siena, Italy Genetica Medica, Azienda Ospedaliera Universitaria Senese, Siena, Italy
| | - Laurence Heidet
- APHP, Centre de Référence des Maladies Rénales Héréditaires de l'Enfant et de l'Adulte (MARHEA), Service de Néphrologie Pédiatrique, Hôpital Necker-Enfants Malades, Paris, France
| | - Helen Storey
- Molecular Genetics Laboratory, Guy's Hospital, London, UK
| | - Michel van Geel
- Clinical Genetics, Maastricht University Medical Centre, Maastricht, the Netherlands
| | - Bertrand Knebelmann
- APHP, Centre de Référence des Maladies Rénales Héréditaires de l'Enfant et de l'Adulte (MARHEA), Service de Néphrologie Pédiatrique, Hôpital Necker-Enfants Malades, Paris, France
| | | | - Nunzia Miglietti
- Clinica Pediatrica, Azienda Ospedaliera Spedali Civili, Brescia, Italy
| | | | | | - John A Sayer
- Institute of Genetic Medicine, Newcastle University, International Centre for Life, Central Parkway, Newcastle upon Tyne, UK
| | | | - Shu Yau
- Molecular Genetics Laboratory, Guy's Hospital, London, UK
| | - Francesca Mari
- Medical Genetics, University of Siena, Siena, Italy Genetica Medica, Azienda Ospedaliera Universitaria Senese, Siena, Italy
| | - Mirella Bruttini
- Medical Genetics, University of Siena, Siena, Italy Genetica Medica, Azienda Ospedaliera Universitaria Senese, Siena, Italy
| | - Francesca Ariani
- Medical Genetics, University of Siena, Siena, Italy Genetica Medica, Azienda Ospedaliera Universitaria Senese, Siena, Italy
| | - Karin Dahan
- Université Catholique de Louvain, Louvain, Belgium
| | - Bert Smeets
- Clinical Genetics, Maastricht University Medical Centre, Maastricht, the Netherlands
| | - Corinne Antignac
- Inserm UMR 1163, Laboratory of Inherited Kidney Diseases, Paris, France Paris Descartes-Sorbonne Paris Cité Université, Imagine Institute, Paris, France APHP, Department of Genetics, Hôpital Necker-Enfants Malades, Paris, France
| | - Frances Flinter
- Department of Clinical Genetics, Guy's & St Thomas' NHS Foundation Trust, Guy's Hospital, London, UK
| | - Alessandra Renieri
- Medical Genetics, University of Siena, Siena, Italy Genetica Medica, Azienda Ospedaliera Universitaria Senese, Siena, Italy
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Wei Q, Zhu H, Qian X, Chen Z, Yao J, Lu Y, Cao X, Xing G. Targeted genomic capture and massively parallel sequencing to identify novel variants causing Chinese hereditary hearing loss. J Transl Med 2014; 12:311. [PMID: 25388789 PMCID: PMC4234825 DOI: 10.1186/s12967-014-0311-1] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2014] [Accepted: 10/23/2014] [Indexed: 11/15/2022] Open
Abstract
Background Hereditary hearing loss is genetically heterogeneous, and hundreds of mutations in than 60 genes are involved in this disease. Therefore, it is difficult to identify the causative gene mutations involved. In this study, we combined targeted genomic capture and massively parallel sequencing (MPS) to address this issue. Methods Using targeted genomic capture and MPS, 104 genes and three microRNA regions were selected and simultaneously sequenced in 23 unrelated probands of Chinese families with nonsyndromic hearing loss. The results were validated by Sanger sequencing for all available members of the probands’ families. To analyze the possible pathogenic functional effects of the variants, three types of prediction programs (Mutation Taster, PROVEAN and SIFT) were used. A total of 195 healthy Chinese Han individuals were compared as controls to verify the novel causative mutations. Results Of the 23 probands, six had mutations in DFNA genes [WFS1 (n = 2), COCH, ACTG1, TMC1, and POU4F3] known to cause autosomal dominant nonsyndromic hearing loss. These included one novel in-frame indel mutation, three novel missense mutations and two reported missense mutations. Furthermore, one proband from a family with recessive DFNB carried two monoallelic mutations in the GJB2 and USH2A genes. All of these mutations co-segregated with the hearing loss phenotype in 36 affected individuals from 7 families and were predicted to be pathogenic. Conclusions Mutations in uncommon deafness genes contribute to a portion of nonsyndromic deafness cases. In the future, critical gene mutations may be accurately and quickly identified in families with hereditary hearing loss by targeted genomic capture and MPS. Electronic supplementary material The online version of this article (doi:10.1186/s12967-014-0311-1) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Qinjun Wei
- Department of Biotechnology, School of Basic Medical Science, Nanjing Medical University, Nanjing, 210029, PR China.
| | - Hongmei Zhu
- Department of Otolaryngology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, 210029, PR China.
| | - Xuli Qian
- Department of Biotechnology, School of Basic Medical Science, Nanjing Medical University, Nanjing, 210029, PR China.
| | - Zhibin Chen
- Department of Otolaryngology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, 210029, PR China.
| | - Jun Yao
- Department of Biotechnology, School of Basic Medical Science, Nanjing Medical University, Nanjing, 210029, PR China.
| | - Yajie Lu
- Department of Biotechnology, School of Basic Medical Science, Nanjing Medical University, Nanjing, 210029, PR China.
| | - Xin Cao
- Department of Biotechnology, School of Basic Medical Science, Nanjing Medical University, Nanjing, 210029, PR China.
| | - Guangqian Xing
- Department of Otolaryngology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, 210029, PR China.
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Beck C, Pérez-Álvarez JC, Sigruener A, Haubner F, Seidler T, Aslanidis C, Strutz J, Schmitz G. Identification and genotype/phenotype correlation of mutations in a large German cohort with hearing loss. Eur Arch Otorhinolaryngol 2014; 272:2765-76. [PMID: 25214170 DOI: 10.1007/s00405-014-3157-5] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2013] [Accepted: 06/15/2014] [Indexed: 12/25/2022]
Abstract
The prevalence of hearing impairment is estimated as approximately 1 on 1,000 newborn children. To assess a higher mutation detection rate in individuals with hearing loss a three-step mutation screening program consisting of GJB2 in first line, then GJB1, GJB3 and GJB6 (second step) and if tested negative or heterozygote, testing of GJA1, GJB4, SLC26A4 and PJVK (third) was performed. Audiograms were derived from all patients to characterize audiological features of GJB2 mutations especially. In 59 patients (31.3%) of the 188 probands, the hearing impairment was due to GJB2 mutations, 45 (23.9%) of these being homozygous for 35delG mutation and 14 (7.4%) compound heterozygous for GJB2 mutations in the coding region of exon 2 whereas no significant sequence variation was found in exon 1. In 22 (11.7%) additional patients a single recessive mutation in GJB2, GJB3, GJB6 and SLC26A4 without a second mutation on the other allele was identified, making genetic counseling difficult. Our study showed significant difference in hearing loss degree in the patients with GJB2-mutations. Forty-five (45.5%) GJB2-cases were identified in 99 individuals diagnosed with severe to profound hearing loss, 14 (17.7%) GJB2-cases were identified in 79 individuals with moderate deafness whereas no clear GJB2 mutation was found in 10 patients with mild hearing loss (p < 0.001). Revealing a high variability of hearing levels in identical genotypes (even intrafamilial), a significant genotype-phenotype correlation could not be established. Based on the identified mutations spectrum and frequencies, speaking mostly of GJB2, a step by step screening for mutations can be devised and in addition may lead to a better stratification of patients for specific therapeutical approaches.
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Affiliation(s)
- Christopher Beck
- Institute for Clinical Chemistry and Laboratory Medicine, University Hospital Regensburg, Franz-Josef-Strauß-Allee 11, 93053, Regensburg, Germany
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Hearing impairment in Estonia: an algorithm to investigate genetic causes in pediatric patients. Adv Med Sci 2014; 58:419-28. [PMID: 24222258 DOI: 10.2478/ams-2013-0001] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
PURPOSE The present study was initiated to establish the etiological causes of early onset hearing loss (HL) among Estonian children between 2000-2009. METHODS The study group consisted of 233 probands who were first tested with an arrayed primer extension assay, which covers 199 mutations in 7 genes (GJB2, GJB6, GJB3, SLC26A4, SLC26A5 genes, and two mitochondrial genes - 12S rRNA, tRNASer(UCN)). From probands whose etiology of HL remained unknown, DNA analysis of congenital cytomegalovirus (CMV) infection and G-banded karyotype and/or chromosomal microarray analysis (CMA) were performed. RESULTS In 110 (47%) cases, the etiology of HL was genetic and in 5 (2%) congenital CMV infection was diagnosed. We found mutations with clinical significance in GJB2 (100 children, 43%) and in 2 mitochondrial genes (2 patients, 1%). A single mutation in SLC26A4 gene was detected in 5 probands (2.2%) and was considered diagnostic. In 4 probands a heterozygous IVS2-2A>G change in the SLC26A5 gene was found. We did not find any instances of homozygosity for this splice variant in the probands. CMA identified in 4 probands chromosomal regions with the loss of one allele. In 2 of them we were able to conclude that the found abnormalities are definitely pathogenic (12q13.3-q14.2 and 17q22-23.2 microdeletion), but the pathogenity of 2 other findings (3p26.2 and 1p33 microdeletion) remained unknown. CONCLUSION This practical diagnostic algorithm confirmed the etiology of early onset HL for 115 Estonian patients (49%). This algorithm may be generalized to other populations for clinical application.
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Li TC, Kuan YH, Ko TY, Li C, Yang JJ. Mechanism of a novel missense mutation, p.V174M, of the human connexin31 (GJB3) in causing nonsyndromic hearing loss. Biochem Cell Biol 2014; 92:251-7. [PMID: 24913888 DOI: 10.1139/bcb-2013-0126] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Hearing loss is the most common sensory disorder, worldwide. In a recent study, we have identified a missense mutation, p.V174M, in the connexin 31 encoded by the GJB3 gene, in a patient with nonsyndromic hearing loss. However, the functional change in the CX31V174M mutant remains unknown. This study compared the intracellular distribution and assembly of the mutant CX31V174M with that of the wild-type (WT) CX31 in HeLa cells, and it examined the effect that the mutant protein had on those cells. A fluorescent localization assay of WT CX31 showed the typical punctuate pattern of a gap junction channel between the neighboring expression cells. Conversely, the p.V174M missense mutation resulted in the accumulation of the mutant protein in the lysosomes rather than in the cytoplasmic membrane. Moreover, dye transfer experiments have also demonstrated that the CX31V174M mutant did not form functional gap junction channels, probably due to the incorrect assembly or the altered properties of the CX31 channels. In addition, we found that CX31V174M-transfection can cause cell death by MTT assay. CX31V174M co-expressed with either CX31WT or CX26WT studies, suggested the impairment of the ability of CX26WT proteins to intracellular trafficking and targeting to the plasma membrane, but did not influence the trafficking of CX31WT. Based on these findings, we suggest that the CX31V174M mutant may have an effect on the formation and function of the gap junction, and CX31V174M has a trans-dominant negative effect on the function of wild types CX26. These results provide a novel molecular explanation for the role that GJB3 plays in hearing loss.
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Affiliation(s)
- Tung-Cheng Li
- a Institute of Medicine, Chung Shan Medical University, Taichung, Taiwan
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JIANG HUA, CHEN JIA, SHAN XINJI, LI YING, HE JIANGUO, YANG BEIBEI. Prevalence and range of GJB2 and SLC26A4 mutations in patients with autosomal recessive non-syndromic hearing loss. Mol Med Rep 2014; 10:379-86. [DOI: 10.3892/mmr.2014.2148] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2013] [Accepted: 03/13/2014] [Indexed: 11/05/2022] Open
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Huang A, Yuan Y, Duan N, Jiang X, Wang B, Liu Y, Kang D, Zhang X, Zhu Q, Dai P. Hearing loss associated with an unusual mutation combination in the gap junction beta 2 (GJB2) gene in a Chinese family. Int J Pediatr Otorhinolaryngol 2014; 78:599-603. [PMID: 24503448 DOI: 10.1016/j.ijporl.2014.01.008] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/30/2013] [Revised: 01/08/2014] [Accepted: 01/08/2014] [Indexed: 10/25/2022]
Abstract
OBJECTIVE To assess the molecular etiology of nonsyndromic sensorineural hearing loss (NSHL) in members of an affected Chinese family. METHODS Common hearing-related genes including gap junction beta 2 (GJB2), SLC26A4, mitochondrial DNA 12S rRNA, GJB3 and GJB6 were examined in a family consisting of a normal hearing father, an NSHL-affected mother, one normal-hearing child and three NSHL-affected children. Specific primers were used in polymerase chain reactions to amplify the coding regions of the above genes from the peripheral blood DNA from each family member, and the genes were analyzed by direct sequencing. The subjects were evaluated for phenotypic characterization using audiometric testing and radiological examination of the inner ear. RESULTS Pathogenic mutations in the GJB2 gene were identified. The affected mother showed a heterozygous G→A transition at nucleotide 232, resulting in an alanine to threonine substitution at codon 78 (p.A78T), and the normal hearing father had a c.35insG insertion mutation. The three affected children displayed heterozygosity for the GJB2 mutations, showing a previously unreported combination of c.35insG and c.232G>A. CONCLUSIONS The GJB2 mutations account for a significant proportion of NSHL in affected individuals worldwide. Genetic and audiological data analysis of a Chinese family with NSHL revealed a novel c.35insG/c.232G>A compound heterozygous state. Our results highlight the complexity of the GJB2 genotypes and phenotypes.
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Affiliation(s)
- Aiping Huang
- Department of Otolaryngology, Head & Neck Surgery, The Second Hospital of Hebei Medical University, Shijiazhuang 050018, Hebei, China; Department of Otolaryngology, Head & Neck Surgery, Chinese PLA General Hospital, Beijing 100853, China
| | - Yongyi Yuan
- Department of Otolaryngology, Head & Neck Surgery, Chinese PLA General Hospital, Beijing 100853, China
| | - Naichao Duan
- Department of Otolaryngology, Head & Neck Surgery, The Second Hospital of Hebei Medical University, Shijiazhuang 050018, Hebei, China
| | - Xinxia Jiang
- Department of Otolaryngology, Head & Neck Surgery, The Second Hospital of Hebei Medical University, Shijiazhuang 050018, Hebei, China
| | - Baoshan Wang
- Department of Otolaryngology, Head & Neck Surgery, The Second Hospital of Hebei Medical University, Shijiazhuang 050018, Hebei, China
| | - Yanping Liu
- Department of Otolaryngology, Head & Neck Surgery, The Second Hospital of Hebei Medical University, Shijiazhuang 050018, Hebei, China
| | - Dongyang Kang
- Department of Otolaryngology, Head & Neck Surgery, Chinese PLA General Hospital, Beijing 100853, China
| | - Xin Zhang
- Department of Otolaryngology, Head & Neck Surgery, Chinese PLA General Hospital, Beijing 100853, China
| | - Qingwen Zhu
- Department of Otolaryngology, Head & Neck Surgery, The Second Hospital of Hebei Medical University, Shijiazhuang 050018, Hebei, China.
| | - Pu Dai
- Department of Otolaryngology, Head & Neck Surgery, Chinese PLA General Hospital, Beijing 100853, China.
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Chen K, Zong L, Liu M, Wang X, Zhou W, Zhan Y, Cao H, Dong C, Tang H, Jiang H. Developing regional genetic counseling for southern Chinese with nonsyndromic hearing impairment: a unique mutational spectrum. J Transl Med 2014; 12:64. [PMID: 24612839 PMCID: PMC3975227 DOI: 10.1186/1479-5876-12-64] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2013] [Accepted: 03/03/2014] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Racial and regional factors are important for the clinical diagnosis of non-syndromic hearing impairment. Comprehensive genetic analysis of deaf patients in different regions of China must be performed to provide effective genetic counseling. To evaluate the mutational spectrum of south Chinese families, we performed genetic analysis for non-syndromic hearing impairment in this population. METHODS Complete clinical evaluations were performed on 701 unrelated patients with non-syndromic hearing impairment from six provinces in south China. Each subject was screened for common mutations, including SLC26A4 c.IVS7-2A > G, c.2168A > G; mitochondrial DNA m.1555A > G, m.1494C > T, m.7444G > A, m.7445A > G; GJB3 c.538C > T, c.547G > A; and WFS1 c.1901A > C, using pyrosequencing. GJB2 and SLC26A4 coding region mutation detection were performed using Sanger sequencing. RESULTS Genetic analysis revealed that among the etiology of non-syndromic hearing impairment, GJB2, SLC26A4, and mitochondrial m.1555A > G mutations accounted for 18.0%, 13.1%, and 0.9%, respectively. Common mutations included GJB2 c.235delC, c.109G > A, SLC26A4 c.IVS7-2A > G, c.1229 T > C, and mitochondrial m.1555A > G. The total mutation rate was 45.1% in all patients examined in south China. Overall, the clear contribution of GJB2, SLC26A4, and mitochondrial m.1555A > G to the etiology of the non-syndromic deafness population in south China was 32.0%. CONCLUSIONS Our study is the first genetic analysis of non-syndromic hearing impairment in south China, and revealed that a clear genetic etiology accounted for 32.0% of non-syndromic hearing cases in patients from these regions. The mutational spectrum of non-syndromic hearing impairment in the south Chinese population provides useful and targeted information to aid in genetic counseling.
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Affiliation(s)
- Kaitian Chen
- Department of Otorhinolaryngology, the First Affiliated Hospital, Sun Yat-sen University and Institute of Otorhinolaryngology, Sun Yat-sen University, Guangzhou 510080, People's Republic of China
| | - Ling Zong
- Department of Otorhinolaryngology, the First Affiliated Hospital, Sun Yat-sen University and Institute of Otorhinolaryngology, Sun Yat-sen University, Guangzhou 510080, People's Republic of China
| | - Min Liu
- Department of Otorhinolaryngology, the First Affiliated Hospital, Sun Yat-sen University and Institute of Otorhinolaryngology, Sun Yat-sen University, Guangzhou 510080, People's Republic of China
| | - Xianren Wang
- Department of Otorhinolaryngology, the First Affiliated Hospital, Sun Yat-sen University and Institute of Otorhinolaryngology, Sun Yat-sen University, Guangzhou 510080, People's Republic of China
| | - Wei Zhou
- Department of Otorhinolaryngology, the First Affiliated Hospital, Sun Yat-sen University and Institute of Otorhinolaryngology, Sun Yat-sen University, Guangzhou 510080, People's Republic of China
| | - Yuan Zhan
- Department of Otorhinolaryngology, the First Affiliated Hospital, Sun Yat-sen University and Institute of Otorhinolaryngology, Sun Yat-sen University, Guangzhou 510080, People's Republic of China
| | - Hui Cao
- Department of Otorhinolaryngology, the First Affiliated Hospital, Sun Yat-sen University and Institute of Otorhinolaryngology, Sun Yat-sen University, Guangzhou 510080, People's Republic of China
| | - Chang Dong
- Department of Otorhinolaryngology, the First Affiliated Hospital, Sun Yat-sen University and Institute of Otorhinolaryngology, Sun Yat-sen University, Guangzhou 510080, People's Republic of China
| | - Haocheng Tang
- Department of Otorhinolaryngology, the First Affiliated Hospital, Sun Yat-sen University and Institute of Otorhinolaryngology, Sun Yat-sen University, Guangzhou 510080, People's Republic of China
| | - Hongyan Jiang
- Department of Otorhinolaryngology, the First Affiliated Hospital, Sun Yat-sen University and Institute of Otorhinolaryngology, Sun Yat-sen University, Guangzhou 510080, People's Republic of China
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Takenouchi T, Hashida N, Torii C, Kosaki R, Takahashi T, Kosaki K. 1p34.3 deletion involving GRIK3: Further clinical implication of GRIK family glutamate receptors in the pathogenesis of developmental delay. Am J Med Genet A 2014; 164A:456-60. [PMID: 24449200 DOI: 10.1002/ajmg.a.36240] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2013] [Accepted: 08/25/2013] [Indexed: 11/12/2022]
Abstract
A growing body of evidence suggests an association between microdeletion/microduplication and schizophrenia/intellectual disability. Abnormal neurogenesis and neurotransmission have been implicated in the pathogenesis of these neuropsychiatric and neurodevelopmental disorders. The kainate/AMPA-type ionotropic glutamate receptor (GRIK = glutamate receptor, ionotropic, kainate) plays a critical role in synaptic potentiation, which is an essential process for learning and memory. Among the five known GRIK family members, haploinsufficiency of GRIK1, GRIK2, and GRIK4 are known to cause developmental delay, whereas the roles of GRIK3 and GRIK5 remain unknown. Herein, we report on a girl who presented with a severe developmental delay predominantly affecting her language and fine motor skills. She had a 2.6-Mb microdeletion in 1p34.3 involving GRIK3, which encodes a principal subunit of the kainate-type ionotropic glutamate receptor. Given its strong expression pattern in the central nervous system and the biological function of GRIK3 in presynaptic neurotransmission, the haploinsufficiency of GRIK3 is likely to be responsible for the severe developmental delay in the proposita. A review of genetic alterations and the phenotypic effects of all the GRIK family members support this hypothesis. The current observation of a microdeletion involving GRIK3, a kainate-type ionotropic glutamate receptor subunit, and the neurodevelopmental manifestation in the absence of major dysmorphism provides further clinical implication of the possible role of GRIK family glutamate receptors in the pathogenesis of developmental delay.
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Affiliation(s)
- Toshiki Takenouchi
- Department of Pediatrics, Keio University School of Medicine, Tokyo, Japan
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Ben-Salem S, Rehm HL, Willems PJ, Tamimi ZA, Ayadi H, Ali BR, Al-Gazali L. Analysis of two Arab families reveals additional support for a DFNB2 nonsyndromic phenotype of MYO7A. Mol Biol Rep 2013; 41:193-200. [PMID: 24194196 DOI: 10.1007/s11033-013-2851-5] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2012] [Accepted: 10/29/2013] [Indexed: 02/05/2023]
Abstract
Variants in the head and tail domains of the MYO7A gene, encoding myosin VIIA, cause Usher syndrome type 1B (USH1B) and nonsyndromic deafness (DFNB2, DFNA11). In order to identify the genetic defect(s) underling profound deafness in two consanguineous Arab families living in UAE, we have sequenced a panel of 19 genes involved in Usher syndrome and nonsyndromic deafness in the index cases of the two families. This analysis revealed a novel homozygous insertion of AG (c.1952_1953insAG/p.C652fsX11) in exon 17 of the MYO7A gene in an Iraqi family, and a homozygous point mutation (c.5660C>T/p.P1887L) in exon 41 affecting the same gene in a large Palestinian family. Moreover, some individuals from the Palestinian family also harbored a novel heterozygous truncating variant (c.1267C>T/p.R423X) in the DFNB31 gene, which is involved in autosomal recessive nonsyndromic deafness type DFNB31 and Usher syndrome type II. Assuming an autosomal recessive mode of inheritance in the two inbred families, we conclude that the homozygous variants in the MYO7A gene are the disease-causing mutations in these families. Furthermore, given the absence of retinal disease in all affected patients examined, particularly a 28 year old patient, suggests that at least one family may segregate a DFNB2 presentation rather than USH1B. This finding further supports the premise that the MYO7A gene is responsible for two distinct diseases and gives evidence that the p.P1887L mutation in a homozygous state may be responsible for nonsyndromic hearing loss.
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Affiliation(s)
- Salma Ben-Salem
- Department of Pathology, College of Medicine and Heath Sciences, United Arab Emirates University, Al Ain, United Arab Emirates,
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