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Ranta-Aho J, Johari M, Udd B. Current advance on distal myopathy genetics. Curr Opin Neurol 2024:00019052-990000000-00182. [PMID: 39017652 DOI: 10.1097/wco.0000000000001299] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/18/2024]
Abstract
PURPOSE OF REVIEW Distal myopathies are a clinically heterogenous group of rare, genetic muscle diseases, that present with weakness in hands and/or feet at onset. Some of these diseases remain accentuated in the distal muscles whereas others may later progress to the proximal muscles. In this review, the latest findings related to genetic and clinical features of distal myopathies are summarized. RECENT FINDINGS Variants in SMPX, DNAJB2, and HSPB6 have been identified as a novel cause of late-onset distal myopathy and neuromyopathy. In oculopharyngodistal myopathies, repeat expansions were identified in two novel disease-causing genes, RILPL1 and ABCD3. In multisystem proteinopathies, variants in HNRNPA1 and TARDBP, genes previously associated with amyotrophic lateral sclerosis, have been shown to cause late-onset distal myopathy without ALS. In ACTN2-related distal myopathy, the first recessive forms of the disease have been described, adding it to the growing list of genes were both dominant and recessive forms of myopathy are present. SUMMARY The identification of novel distal myopathy genes and pathogenic variants contribute to our ability to provide a final molecular diagnosis to a larger number of patients and increase our overall understanding of distal myopathy genetics and pathology.
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Affiliation(s)
- Johanna Ranta-Aho
- Folkhälsan Research Center
- Department of Medical Genetics, Medicum, University of Helsinki, Helsinki, Finland
| | - Mridul Johari
- Folkhälsan Research Center
- Department of Medical Genetics, Medicum, University of Helsinki, Helsinki, Finland
- Harry Perkins Institute of Medical Research, Centre for Medical Research, University of Western Australia, Nedlands, Western Australia, Australia
| | - Bjarne Udd
- Folkhälsan Research Center
- Tampere Neuromuscular Center, Tampere University and Tampere University Hospital, Tampere, Finland
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2
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Diana A, Ghilardi A, Del Giacco L. Differentiation and functioning of the lateral line organ in zebrafish require Smpx activity. Sci Rep 2024; 14:7862. [PMID: 38570547 PMCID: PMC10991396 DOI: 10.1038/s41598-024-58138-z] [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: 10/12/2023] [Accepted: 03/26/2024] [Indexed: 04/05/2024] Open
Abstract
The small muscle protein, X-linked (SMPX) gene encodes a cytoskeleton-associated protein, highly expressed in the inner ear hair cells (HCs), possibly regulating auditory function. In the last decade, several mutations in SMPX have been associated with X-chromosomal progressive non syndromic hearing loss in humans and, in line with this, Smpx-deficient animal models, namely zebrafish and mouse, showed significant impairment of inner ear HCs development, maintenance, and functioning. In this work, we uncovered smpx expression in the neuromast mechanosensory HCs of both Anterior and Posterior Lateral Line (ALL and PLL, respectively) of zebrafish larvae and focused our attention on the PLL. Smpx was subcellularly localized throughout the cytoplasm of the HCs, as well as in their primary cilium. Loss-of-function experiments, via both morpholino-mediated gene knockdown and CRISPR/Cas9 F0 gene knockout, revealed that the lack of Smpx led to fewer properly differentiated and functional neuromasts, as well as to a smaller PLL primordium (PLLp), the latter also Smpx-positive. In addition, the kinocilia of Smpx-deficient neuromast HCs appeared structurally and numerically altered. Such phenotypes were associated with a significant reduction in the mechanotransduction activity of the neuromast HCs, in line with their positivity for Smpx. In summary, this work highlights the importance of Smpx in lateral line development and, specifically, in proper HCs differentiation and/or maintenance, and in the mechanotransduction process carried out by the neuromast HCs. Because lateral line HCs are both functionally and structurally analogous to the cochlear HCs, the neuromasts might represent an invaluable-and easily accessible-tool to dissect the role of Smpx in HCs development/functioning and shed light on the underlying mechanisms involved in hearing loss.
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Affiliation(s)
- Alberto Diana
- Department of Biosciences, Università degli Studi di Milano, Via Celoria 26, 20133, Milan, Italy
| | - Anna Ghilardi
- Department of Biosciences, Università degli Studi di Milano, Via Celoria 26, 20133, Milan, Italy
| | - Luca Del Giacco
- Department of Biosciences, Università degli Studi di Milano, Via Celoria 26, 20133, Milan, Italy.
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3
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Feng Y, Hu S, Zhao S, Chen M. Recent advances in genetic etiology of non-syndromic deafness in children. Front Neurosci 2023; 17:1282663. [PMID: 37928735 PMCID: PMC10620706 DOI: 10.3389/fnins.2023.1282663] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2023] [Accepted: 10/04/2023] [Indexed: 11/07/2023] Open
Abstract
Congenital auditory impairment is a prevalent anomaly observed in approximately 2-3 per 1,000 infants. The consequences associated with hearing loss among children encompass the decline of verbal communication, linguistic skills, educational progress, social integration, cognitive aptitude, and overall well-being. Approaches to reversing or preventing genetic hearing loss are limited. Patients with mild and moderate hearing loss can only use hearing aids, while those with severe hearing loss can only acquire speech and language through cochlear implants. Both environmental and genetic factors contribute to the occurrence of congenital hearing loss, and advancements in our understanding of the pathophysiology and molecular mechanisms underlying hearing loss, coupled with recent progress in genetic testing techniques, will facilitate the development of innovative approaches for treatment and screening. In this paper, the latest research progress in genetic etiology of non-syndromic deafness in children with the highest incidence is summarized in order to provide help for personalized diagnosis and treatment of deafness in children.
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Wang Y, Zhang C, Peng W, Du H, Xi Y, Xu Z. RBM24 is required for mouse hair cell development through regulating pre-mRNA alternative splicing and mRNA stability. J Cell Physiol 2023; 238:1095-1110. [PMID: 36947695 DOI: 10.1002/jcp.31003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2022] [Revised: 02/28/2023] [Accepted: 03/06/2023] [Indexed: 03/24/2023]
Abstract
As the sensory receptor cells in vertebrate inner ear and lateral lines, hair cells are characterized by the hair bundle that consists of one tubulin-based kinocilium and dozens of actin-based stereocilia on the apical surface of each hair cell. Hair cell development is tightly regulated, and deficits in this process usually lead to hearing loss and/or balance dysfunctions. RNA-binding motif protein 24 (RBM24) is an RNA-binding protein that is specifically expressed in the hair cells in the inner ear. Previously, we showed that RBM24 affects hair cell development in zebrafish by regulating messenger RNA (mRNA) stability. In the present work, we further investigate the role of RBM24 in hearing and balance using conditional knockout mice. Our results show that Rbm24 knockout results in severe hearing and balance deficits. Hair cell development is significantly affected in Rbm24 knockout cochlea, as the hair bundles are poorly developed and eventually degenerated. Hair bundle disorganization is also observed in Rbm24 knockout vestibular hair cells, although to a lesser extent. Consistently, significant hair cell loss is observed in the cochlea but not vestibule. RNAseq analysis identified several genes whose mRNA stability or pre-mRNA alternative splicing is affected by Rbm24 knockout. Among them are Cdh23, Pcdh15, and Myo7a, which have been shown to play important roles in stereocilia development as well as mechano-electrical transduction. Taken together, our present work suggests that RBM24 is required for mouse hair cell development through regulating pre-mRNA alternative splicing as well as mRNA stability.
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Affiliation(s)
- Yanfei Wang
- Shandong Provincial Key Laboratory of Animal Cells and Developmental Biology and Key Laboratory for Experimental Teratology of the Ministry of Education, School of Life Sciences, Shandong University, Qingdao, Shandong, China
| | - Cuiqiao Zhang
- Shandong Provincial Key Laboratory of Animal Cells and Developmental Biology and Key Laboratory for Experimental Teratology of the Ministry of Education, School of Life Sciences, Shandong University, Qingdao, Shandong, China
| | - Wu Peng
- Shandong Provincial Key Laboratory of Animal Cells and Developmental Biology and Key Laboratory for Experimental Teratology of the Ministry of Education, School of Life Sciences, Shandong University, Qingdao, Shandong, China
| | - Haibo Du
- Shandong Provincial Key Laboratory of Animal Cells and Developmental Biology and Key Laboratory for Experimental Teratology of the Ministry of Education, School of Life Sciences, Shandong University, Qingdao, Shandong, China
| | - Yuehui Xi
- Shandong Provincial Key Laboratory of Animal Cells and Developmental Biology and Key Laboratory for Experimental Teratology of the Ministry of Education, School of Life Sciences, Shandong University, Qingdao, Shandong, China
| | - Zhigang Xu
- Shandong Provincial Key Laboratory of Animal Cells and Developmental Biology and Key Laboratory for Experimental Teratology of the Ministry of Education, School of Life Sciences, Shandong University, Qingdao, Shandong, China
- Shandong Provincial Collaborative Innovation Center of Cell Biology, Shandong Normal University, Jinan, Shandong, China
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5
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Azadegan-Dehkordi F, Koohiyan M, Hoseini M. An update on autosomal recessive hearing loss and loci involved in it. INDIAN JOURNAL OF OTOLOGY 2022. [DOI: 10.4103/indianjotol.indianjotol_115_21] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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6
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Liang F, Fu X, Ding S, Li L. Use of a Network-Based Method to Identify Latent Genes Associated with Hearing Loss in Children. Front Cell Dev Biol 2021; 9:783500. [PMID: 34912812 PMCID: PMC8667072 DOI: 10.3389/fcell.2021.783500] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2021] [Accepted: 11/15/2021] [Indexed: 11/13/2022] Open
Abstract
Hearing loss is a total or partial inability to hear. Approximately 5% of people worldwide experience this condition. Hearing capacity is closely related to language, social, and basic emotional development; hearing loss is particularly serious in children. The pathogenesis of childhood hearing loss remains poorly understood. Here, we sought to identify new genes potentially associated with two types of hearing loss in children: congenital deafness and otitis media. We used a network-based method incorporating a random walk with restart algorithm, as well as a protein-protein interaction framework, to identify genes potentially associated with either pathogenesis. A following screening procedure was performed and 18 and 87 genes were identified, which potentially involved in the development of congenital deafness or otitis media, respectively. These findings provide novel biomarkers for clinical screening of childhood deafness; they contribute to a genetic understanding of the pathogenetic mechanisms involved.
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Affiliation(s)
- Feng Liang
- Anaesthesia Department, China-Japan Union Hospital, JiLin University, Changchun, China
| | - Xin Fu
- Anaesthesia Department, China-Japan Union Hospital, JiLin University, Changchun, China
| | - ShiJian Ding
- School of Life Sciences, Shanghai University, Shanghai, China
| | - Lin Li
- Department of Otorhinolaryngology Head and Neck Surgery, China-Japan Union Hospital of Jilin University, Changchun, China
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7
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Tu H, Zhang A, Fu X, Xu S, Bai X, Wang H, Gao J. SMPX Deficiency Causes Stereocilia Degeneration and Progressive Hearing Loss in CBA/CaJ Mice. Front Cell Dev Biol 2021; 9:750023. [PMID: 34722533 PMCID: PMC8551870 DOI: 10.3389/fcell.2021.750023] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2021] [Accepted: 09/17/2021] [Indexed: 11/13/2022] Open
Abstract
The small muscle protein, x-linked (SMPX) encodes a small protein containing 88 amino acids. Malfunction of this protein can cause a sex-linked non-syndromic hearing loss, named X-linked deafness 4 (DFNX4). Herein, we reported a point mutation and a frameshift mutation in two Chinese families who developed gradual hearing loss with age. To explore the impaired sites in the hearing system and the mechanism of DFNX4, we established and validated an Smpx null mouse model using CRISPR-Cas9. By analyzing auditory brainstem response (ABR), male Smpx null mice showed a progressive hearing loss starting from high frequency at the 3rd month. Hearing loss in female mice was milder and occurred later compared to male mice, which was very similar to human beings. Through morphological analyses of mice cochleas, we found the hair cell bundles progressively degenerated from the shortest row. Cellular edema occurred at the end phase of stereocilia degeneration, followed by cell death. By transfecting exogenous fluorescent Smpx into living hair cells, Smpx was observed to be expressed in stereocilia. Through noise exposure, it was shown that Smpx might participate in maintaining hair cell bundles. This Smpx knock-out mouse might be used as a suitable model to explore the pathology of DFNX4.
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Affiliation(s)
- Hailong Tu
- School of Life Sciences, Shandong Provincial ENT Hospital, Shandong University, Jinan, China
| | - Aizhen Zhang
- School of Life Sciences, Shandong Provincial ENT Hospital, Shandong University, Jinan, China
| | - Xiaolong Fu
- School of Life Sciences, Shandong Provincial ENT Hospital, Shandong University, Jinan, China
| | - Shiqi Xu
- University of Edinburgh Institute, Zhejiang University School of Medicine, Zhejiang University, Haining, China
| | - Xiaohui Bai
- Otolaryngology-Head and Neck Surgery, Shandong Provincial ENT Hospital, Jinan, China
| | - Haibo Wang
- School of Life Sciences, Shandong Provincial ENT Hospital, Shandong University, Jinan, China.,Otolaryngology-Head and Neck Surgery, Shandong Provincial ENT Hospital, Jinan, China
| | - Jiangang Gao
- School of Life Sciences, Shandong Provincial ENT Hospital, Shandong University, Jinan, China
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8
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Johari M, Sarparanta J, Vihola A, Jonson PH, Savarese M, Jokela M, Torella A, Piluso G, Said E, Vella N, Cauchi M, Magot A, Magri F, Mauri E, Kornblum C, Reimann J, Stojkovic T, Romero NB, Luque H, Huovinen S, Lahermo P, Donner K, Comi GP, Nigro V, Hackman P, Udd B. Missense mutations in small muscle protein X-linked (SMPX) cause distal myopathy with protein inclusions. Acta Neuropathol 2021; 142:375-393. [PMID: 33974137 PMCID: PMC8270885 DOI: 10.1007/s00401-021-02319-x] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2021] [Revised: 04/26/2021] [Accepted: 04/26/2021] [Indexed: 01/05/2023]
Abstract
Using
deep phenotyping and high-throughput sequencing, we have identified a novel type of distal myopathy caused by mutations in the Small muscle protein X-linked (SMPX) gene. Four different missense mutations were identified in ten patients from nine families in five different countries, suggesting that this disease could be prevalent in other populations as well. Haplotype analysis of patients with similar ancestry revealed two different founder mutations in Southern Europe and France, indicating that the prevalence in these populations may be higher. In our study all patients presented with highly similar clinical features: adult-onset, usually distal more than proximal limb muscle weakness, slowly progressing over decades with preserved walking. Lower limb muscle imaging showed a characteristic pattern of muscle involvement and fatty degeneration. Histopathological and electron microscopic analysis of patient muscle biopsies revealed myopathic findings with rimmed vacuoles and the presence of sarcoplasmic inclusions, some with amyloid-like characteristics. In silico predictions and subsequent cell culture studies showed that the missense mutations increase aggregation propensity of the SMPX protein. In cell culture studies, overexpressed SMPX localized to stress granules and slowed down their clearance.
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Affiliation(s)
- Mridul Johari
- Folkhälsan Research Center, Helsinki, Finland.
- Department of Medical Genetics, Medicum, University of Helsinki, Helsinki, Finland.
| | - Jaakko Sarparanta
- Folkhälsan Research Center, Helsinki, Finland
- Department of Medical Genetics, Medicum, University of Helsinki, Helsinki, Finland
| | - Anna Vihola
- Folkhälsan Research Center, Helsinki, Finland
- Department of Medical Genetics, Medicum, University of Helsinki, Helsinki, Finland
- Neuromuscular Research Center, Fimlab Laboratories, Tampere University and University Hospital, Tampere, Finland
| | - Per Harald Jonson
- Folkhälsan Research Center, Helsinki, Finland
- Department of Medical Genetics, Medicum, University of Helsinki, Helsinki, Finland
| | - Marco Savarese
- Folkhälsan Research Center, Helsinki, Finland
- Department of Medical Genetics, Medicum, University of Helsinki, Helsinki, Finland
| | - Manu Jokela
- Neuromuscular Research Center, Department of Neurology, Tampere University and University Hospital, Tampere, Finland
- Division of Clinical Neurosciences, Department of Neurology, Turku University Hospital, Turku, Finland
| | - Annalaura Torella
- Dipartimento di Medicina di Precisione, Università degli Studi della Campania "Luigi Vanvitelli", Naples, Italy
| | - Giulio Piluso
- Dipartimento di Medicina di Precisione, Università degli Studi della Campania "Luigi Vanvitelli", Naples, Italy
| | - Edith Said
- Section of Medical Genetics, Mater Dei Hospital, Msida, Malta
- Department of Anatomy and Cell Biology, Faculty of Medicine and Surgery, University of Malta, Msida, Malta
| | - Norbert Vella
- Neuroscience Department, Mater Dei Hospital, Msida, Malta
| | - Marija Cauchi
- Neuroscience Department, Mater Dei Hospital, Msida, Malta
| | - Armelle Magot
- Neuromuscular Disease Center AOC, University Hospital Nantes, Nantes, France
| | - Francesca Magri
- IRCCS Foundation Ca' Granda Ospedale Maggiore Policlinico, Neurology Unit, Milan, Italy
| | - Eleonora Mauri
- IRCCS Foundation Ca' Granda Ospedale Maggiore Policlinico, Neurology Unit, Milan, Italy
| | | | - Jens Reimann
- Department of Neurology, University Hospital Bonn, Bonn, Germany
| | - Tanya Stojkovic
- AP-HP, Institute of Myology, Centre de Référence des Maladies Neuromusculaires, Hôpital Pitié-Salpêtrière, Paris, France
| | - Norma B Romero
- Neuromuscular Morphology Unit, Institute of Myology, Myology Research Centre INSERM, Sorbonne Université, Hôpital Pitié-Salpêtrière, Paris, France
| | - Helena Luque
- Folkhälsan Research Center, Helsinki, Finland
- Department of Medical Genetics, Medicum, University of Helsinki, Helsinki, Finland
| | - Sanna Huovinen
- Department of Pathology, Fimlab Laboratories, Tampere University Hospital, Tampere, Finland
| | - Päivi Lahermo
- Institute for Molecular Medicine Finland FIMM, Technology Centre, University of Helsinki, Helsinki, Finland
| | - Kati Donner
- Institute for Molecular Medicine Finland FIMM, Technology Centre, University of Helsinki, Helsinki, Finland
| | - Giacomo Pietro Comi
- IRCCS Fondazione Ca' Granda Ospedale Maggiore Policlinico, Neuromuscular and Rare Disease Unit, Milan, Italy
- Dino Ferrari Center, Department of Pathophysiology and Transplantation, University of Milan, Milan, Italy
| | - Vincenzo Nigro
- Dipartimento di Medicina di Precisione, Università degli Studi della Campania "Luigi Vanvitelli", Naples, Italy
- Telethon Institute of Genetics and Medicine (TIGEM), Pozzuoli, Italy
| | - Peter Hackman
- Folkhälsan Research Center, Helsinki, Finland
- Department of Medical Genetics, Medicum, University of Helsinki, Helsinki, Finland
| | - Bjarne Udd
- Folkhälsan Research Center, Helsinki, Finland
- Department of Medical Genetics, Medicum, University of Helsinki, Helsinki, Finland
- Neuromuscular Research Center, Department of Neurology, Tampere University and University Hospital, Tampere, Finland
- Department of Neurology, Vaasa Central Hospital, Vaasa, Finland
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Ghilardi A, Diana A, Bacchetta R, Santo N, Ascagni M, Prosperi L, Del Giacco L. Inner Ear and Muscle Developmental Defects in Smpx-Deficient Zebrafish Embryos. Int J Mol Sci 2021; 22:ijms22126497. [PMID: 34204426 PMCID: PMC8235540 DOI: 10.3390/ijms22126497] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2021] [Revised: 06/09/2021] [Accepted: 06/12/2021] [Indexed: 12/20/2022] Open
Abstract
The last decade has witnessed the identification of several families affected by hereditary non-syndromic hearing loss (NSHL) caused by mutations in the SMPX gene and the loss of function has been suggested as the underlying mechanism. In the attempt to confirm this hypothesis we generated an Smpx-deficient zebrafish model, pointing out its crucial role in proper inner ear development. Indeed, a marked decrease in the number of kinocilia together with structural alterations of the stereocilia and the kinocilium itself in the hair cells of the inner ear were observed. We also report the impairment of the mechanotransduction by the hair cells, making SMPX a potential key player in the construction of the machinery necessary for sound detection. This wealth of evidence provides the first possible explanation for hearing loss in SMPX-mutated patients. Additionally, we observed a clear muscular phenotype consisting of the defective organization and functioning of muscle fibers, strongly suggesting a potential role for the protein in the development of muscle fibers. This piece of evidence highlights the need for more in-depth analyses in search for possible correlations between SMPX mutations and muscular disorders in humans, thus potentially turning this non-syndromic hearing loss-associated gene into the genetic cause of dysfunctions characterized by more than one symptom, making SMPX a novel syndromic gene.
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Affiliation(s)
- Anna Ghilardi
- Department of Biosciences, Università degli Studi di Milano, Via Celoria 26, 20133 Milan, Italy; (A.G.); (A.D.); (L.P.)
| | - Alberto Diana
- Department of Biosciences, Università degli Studi di Milano, Via Celoria 26, 20133 Milan, Italy; (A.G.); (A.D.); (L.P.)
| | - Renato Bacchetta
- Department of Environmental Science and Policy, Università degli Studi di Milano, 20133 Milan, Italy;
| | - Nadia Santo
- Unitech NOLIMITS, Università degli Studi di Milano, 20133 Milan, Italy; (N.S.); (M.A.)
| | - Miriam Ascagni
- Unitech NOLIMITS, Università degli Studi di Milano, 20133 Milan, Italy; (N.S.); (M.A.)
| | - Laura Prosperi
- Department of Biosciences, Università degli Studi di Milano, Via Celoria 26, 20133 Milan, Italy; (A.G.); (A.D.); (L.P.)
| | - Luca Del Giacco
- Department of Biosciences, Università degli Studi di Milano, Via Celoria 26, 20133 Milan, Italy; (A.G.); (A.D.); (L.P.)
- Correspondence:
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Guo Y, Hao Y, Zhang D, Xu H, Yu D, Lv J, Fu Z, Han S, Guo F, Bai J, Guan G. A novel missense mutation in SMPX causes a rare form of X-linked postlingual sensorineural hearing loss in a Chinese family. Transl Pediatr 2021; 10:378-387. [PMID: 33708524 PMCID: PMC7944167 DOI: 10.21037/tp-20-435] [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] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
BACKGROUND X-linked deafness-4 (DFNX4) caused by the functional loss of the SMPX gene is one form of nonsyndromic hearing loss with postlingual onset. This study aimed to investigate the cause of X-linked inherited sensorineural nonsyndromic hearing loss in a four-generation Chinese family and to explain the reason for extremely different hearing phenotypes between the proband and other family members. METHODS Whole-exome sequencing (WES) and co-segregation analysis were used to identify the pathogenic variants. Furthermore, methylation differences among the androgen receptor genes were utilized to investigate whether the severe phenotype of the proband is related to X-chromosome inactivation (Xi). RESULTS We described in detail the clinical characteristics of the family and identified a novel missense mutation (c.262C>G: p.Gln88Glu) in SMPX by WES. This variant was co-segregated with the postlingual hearing loss phenotype and was absent in 300 normal controls. Also, we found that the proband, a 4-year-old female, carries two new compound heterozygous mutations (c.9259G>A: p.Val3087Ile and c.8576G>A: p.Arg2859His) in the USH2A gene, but to date without any other symptoms except profound sensorineural hearing loss. Additionally, analysis of X-chromosome inactivation indicated moderate skewing in the proband, which is probably related to the heterogeneity of clinical characteristics. CONCLUSIONS This is the first study to report a missense mutation of SMPX in a Chinese family. Our findings have enriched the mutation and phenotypic spectrum of the SMPX gene.
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Affiliation(s)
- Yingyuan Guo
- Department of Otolaryngology, The Second Hospital of Jilin University, Changchun, China
| | - Yanru Hao
- Department of Otolaryngology, The Second Hospital of Jilin University, Changchun, China
| | - Dejun Zhang
- Department of Otolaryngology, The Second Hospital of Jilin University, Changchun, China
| | - Hongen Xu
- Precision Medicine Center, Academy of Medical Science, Zhengzhou University, Zhengzhou, China
| | - Duojiao Yu
- Department of Otolaryngology, The Second Hospital of Jilin University, Changchun, China
| | - Jingmao Lv
- Department of Spinal Surgery, Jilin Province People's Hospital, Changchun, China
| | - Zeming Fu
- Department of Otolaryngology, The Second Hospital of Jilin University, Changchun, China
| | - Shuang Han
- Department of Otolaryngology, The Second Hospital of Jilin University, Changchun, China
| | - Fang Guo
- Department of Otolaryngology, The Second Hospital of Jilin University, Changchun, China
| | - Jie Bai
- Department of Otolaryngology, The Second Hospital of Jilin University, Changchun, China
| | - Guofang Guan
- Department of Otolaryngology, The Second Hospital of Jilin University, Changchun, China
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11
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Zhang Y, Wang Y, Yao X, Wang C, Chen F, Liu D, Shao M, Xu Z. Rbm24a Is Necessary for Hair Cell Development Through Regulating mRNA Stability in Zebrafish. Front Cell Dev Biol 2020; 8:604026. [PMID: 33392193 PMCID: PMC7773828 DOI: 10.3389/fcell.2020.604026] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2020] [Accepted: 12/01/2020] [Indexed: 11/30/2022] Open
Abstract
Hair cells in the inner ear and lateral lines are mechanosensitive receptor cells whose development and function are tightly regulated. Several transcription factors as well as splicing factors have been identified to play important roles in hair cell development, whereas the role of RNA stability in this process is poorly understood. In the present work, we report that RNA-binding motif protein 24a (Rbm24a) is indispensable for hair cell development in zebrafish. Rbm24a expression is detected in the inner ear as well as lateral line neuromasts. Albeit rbm24a deficient zebrafish do not survive beyond 9 days post fertilization (dpf) due to effects outside of the inner ear, rbm24a deficiency does not affect the early development of inner ear except for delayed otolith formation and semicircular canal fusion. However, hair cell development is severely affected and hair bundle is disorganized in rbm24a mutants. As a result, the auditory and vestibular function of rbm24a mutants are compromised. RNAseq analyses identified several Rbm24a-target mRNAs that are directly bound by Rbm24a and are dysregulated in rbm24a mutants. Among the identified Rbm24a-target genes, lrrc23, dfna5b, and smpx are particularly interesting as their dysregulation might contribute to the inner ear phenotypes in rbm24a mutants. In conclusion, our data suggest that Rbm24a affects hair cell development in zebrafish through regulating mRNA stability.
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Affiliation(s)
- Yan Zhang
- Shandong Provincial Key Laboratory of Animal Cells and Developmental Biology, School of Life Sciences, Shandong University, Qingdao, China
| | - Yanfei Wang
- Shandong Provincial Key Laboratory of Animal Cells and Developmental Biology, School of Life Sciences, Shandong University, Qingdao, China
| | - Xuebo Yao
- Shandong Provincial Key Laboratory of Animal Cells and Developmental Biology, School of Life Sciences, Shandong University, Qingdao, China
| | - Changquan Wang
- Department of Biomedical Engineering, Southern University of Science and Technology, Shenzhen, China
| | - Fangyi Chen
- Department of Biomedical Engineering, Southern University of Science and Technology, Shenzhen, China
| | - Dong Liu
- Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education, Co-Innovation Center of Neuroregeneration, School of Life Sciences, Nantong University, Nantong, China
| | - Ming Shao
- Shandong Provincial Key Laboratory of Animal Cells and Developmental Biology, School of Life Sciences, Shandong University, Qingdao, China
| | - Zhigang Xu
- Shandong Provincial Key Laboratory of Animal Cells and Developmental Biology, School of Life Sciences, Shandong University, Qingdao, China.,Shandong Provincial Collaborative Innovation Center of Cell Biology, Shandong Normal University, Jinan, China
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12
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Yang LM, Stout L, Rauchman M, Ornitz DM. Analysis of FGF20-regulated genes in organ of Corti progenitors by translating ribosome affinity purification. Dev Dyn 2020; 249:1217-1242. [PMID: 32492250 DOI: 10.1002/dvdy.211] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2020] [Revised: 05/26/2020] [Accepted: 05/27/2020] [Indexed: 12/20/2022] Open
Abstract
BACKGROUND Understanding the mechanisms that regulate hair cell (HC) differentiation in the organ of Corti (OC) is essential to designing genetic therapies for hearing loss due to HC loss or damage. We have previously identified Fibroblast Growth Factor 20 (FGF20) as having a key role in HC and supporting cell differentiation in the mouse OC. To investigate the genetic landscape regulated by FGF20 signaling in OC progenitors, we employ Translating Ribosome Affinity Purification combined with Next Generation RNA Sequencing (TRAPseq) in the Fgf20 lineage. RESULTS We show that TRAPseq targeting OC progenitors effectively enriched for RNA from this rare cell population. TRAPseq identified differentially expressed genes (DEGs) downstream of FGF20, including Etv4, Etv5, Etv1, Dusp6, Hey1, Hey2, Heyl, Tectb, Fat3, Cpxm2, Sall1, Sall3, and cell cycle regulators such as Cdc20. Analysis of Cdc20 conditional-null mice identified decreased cochlea length, while analysis of Sall1-null and Sall1-ΔZn2-10 mice, which harbor a mutation that causes Townes-Brocks syndrome, identified a decrease in outer hair cell number. CONCLUSIONS We present two datasets: genes with enriched expression in OC progenitors, and DEGs downstream of FGF20 in the embryonic day 14.5 cochlea. We validate select DEGs via in situ hybridization and in vivo functional studies in mice.
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Affiliation(s)
- Lu M Yang
- Department of Developmental Biology, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Lisa Stout
- Division of Nephrology, Department of Medicine, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Michael Rauchman
- Division of Nephrology, Department of Medicine, Washington University School of Medicine, St. Louis, Missouri, USA
| | - David M Ornitz
- Department of Developmental Biology, Washington University School of Medicine, St. Louis, Missouri, USA
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13
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Expression pattern of the small muscle protein, X-linked (smpx) gene during zebrafish embryonic and larval developmental stages. Gene Expr Patterns 2020; 36:119110. [PMID: 32197943 DOI: 10.1016/j.gep.2020.119110] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2020] [Revised: 03/09/2020] [Accepted: 03/16/2020] [Indexed: 11/22/2022]
Abstract
The small muscle protein, X-linked (SMPX) gene encodes a cytoskeleton-associated protein, highly expressed in both cardiac and skeletal muscles, as well as in fetal inner ears, with suggested roles as mechanotransductor. Recently, several mutations in the SMPX gene have been associated with X-chromosomal progressive deafness in human. However, very little information is known concerning the roles of SMPX, and no in-vivo models are currently available. Therefore, we characterized the zebrafish ortholog of SMPX to pave the way towards the establishment of a biotool for future functional studies. Despite the genome duplication occurred in the ancestry of teleosts, zebrafish retain only one copy of smpx which shares a high degree of similarity with the mammalian counterpart in terms of genomic organization, syntenic map, and encoded protein. RT-PCR, as well as whole-mount in-situ hybridization and immunofluorescence analyses, revealed that smpx is expressed in several embryonic areas starting from the 4-somite stage. Specifically, smpx mRNA marked the Kupffer's vesicle (KV), the somites, the myocardium, the hair cells of the anterior and the posterior macula of the inner ear, the pronephric ducts, and the muscles of the branchial arches, eyes and pectoral fins. According to our data, zebrafish smpx expression pattern closely resembles that observed in mouse and human, supporting the notion that zebrafish might represent a suitable in-vivo model to disclose the cellular and molecular mechanisms underlying the involvement of SMPX in development and disease.
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14
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Small fish, big prospects: using zebrafish to unravel the mechanisms of hereditary hearing loss. Hear Res 2020; 397:107906. [PMID: 32063424 DOI: 10.1016/j.heares.2020.107906] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/08/2019] [Revised: 01/13/2020] [Accepted: 01/29/2020] [Indexed: 12/16/2022]
Abstract
Over the past decade, advancements in high-throughput sequencing have greatly enhanced our knowledge of the mutational signatures responsible for hereditary hearing loss. In its present state, the field has a largely uncensored view of protein coding changes in a growing number of genes that have been associated with hereditary hearing loss, and many more that have been proposed as candidate genes. Sequencing data can now be generated using methods that have become widespread and affordable. The greatest hurdles facing the field concern functional validation of uncharacterized genes and rapid application to human diseases, including hearing and balance disorders. To date, over 30 hearing-related disease models exist in zebrafish. New genome editing technologies, including CRISPR/Cas9 will accelerate the functional validation of hearing loss genes and variants in zebrafish. Here, we discuss current progress in the field and recent advances in genome editing approaches.
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15
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Arifuzzaman M, Mitra S, Das R, Hamza A, Absar N, Dash R. In silico analysis of nonsynonymous single-nucleotide polymorphisms (nsSNPs) of the SMPX gene. Ann Hum Genet 2019; 84:54-71. [PMID: 31583691 DOI: 10.1111/ahg.12350] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2019] [Revised: 07/06/2019] [Accepted: 08/08/2019] [Indexed: 02/06/2023]
Abstract
Mutations in the SMPX gene can disrupt the regular activity of the SMPX protein, which is involved in the hearing process. Recent reports showing a link between nonsynonymous single-nucleotide polymorphisms (nsSNPs) in SMPX and hearing loss, thus classifying deleterious SNPs in SMPX will be an uphill task before designing a more extensive population study. In this study, damaging nsSNPs of SMPX from the dbSNP database were identified by using 13 bioinformatics tools. Initially, the impact of nsSNPs in the SMPX gene were evaluated through different in silico predictors; and the deleterious convergent changes were analyzed by energy-minimization-guided residual network analysis. In addition, the pathogenic effects of mutations in SMPX-mediated protein-protein interactions were also characterized by structural modeling and binding energy calculations. A total of four mutations (N19D, A29T, K54N, and S71L) were found to be highly deleterious by all the tools, which are located at highly conserved regions. Furthermore, all four mutants showed structural alterations, and the communities of amino acids for mutant proteins were readily changed, compared to the wild-type. Among them, A29T (rs772775896) was revealed as the most damaging nsSNP, which caused significant structural deviation of the SMPX protein, as a result reducing the binding affinity to other functional partners. These findings reflect the computational insights into the deleterious role of nsSNPs in SMPX, which might be helpful for subjecting wet-lab confirmatory analysis.
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Affiliation(s)
- Md Arifuzzaman
- College of Pharmacy, Yeungnam University, Gyeongbuk, Republic of Korea
| | - Sarmistha Mitra
- Plasma Bioscience Research Center, Plasma-Bio Display, Kwangwoon University, Seoul, Republic of Korea
| | - Raju Das
- Department of Biochemistry and Biotechnology, University of Science & Technology Chittagong, Chittagong, Bangladesh
| | - Amir Hamza
- Department of Biochemistry, Hallym University, Gangwon, Republic of Korea
| | - Nurul Absar
- Department of Biochemistry and Biotechnology, University of Science & Technology Chittagong, Chittagong, Bangladesh
| | - Raju Dash
- Department of Anatomy, Dongguk University Graduate School of Medicine, Gyeongju, Republic of Korea
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16
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Lv Y, Gu J, Qiu H, Li H, Zhang Z, Yin S, Mao Y, Kong L, Liang B, Jiang H, Liu C. Whole-exome sequencing identifies a donor splice-site variant in SMPX that causes rare X-linked congenital deafness. Mol Genet Genomic Med 2019; 7:e967. [PMID: 31478598 PMCID: PMC6825843 DOI: 10.1002/mgg3.967] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2019] [Revised: 07/31/2019] [Accepted: 08/05/2019] [Indexed: 12/17/2022] Open
Abstract
Background X‐linked deafness‐4 (DFNX4) caused by functional loss of SMPX is a nonsyndromic form of progressive hearing loss with post‐lingual onset. Herein, we describe a male neonate from an ethnic Han Chinese family who presented with congenital deafness. Methods The proband and the family members were subjected to comprehensively hearing screen. Genetic testing was carried out using whole‐exome sequencing (WES). The result was verified by Sanger sequencing. Functional characterization of the identified variant was completed by reverse transcription PCR (RT‐PCR), Sanger sequencing, and fluorogenic quantitative PCR (qPCR). Results The proband was diagnosed with progressive sensorineural hearing loss. The proband's mother showed normal hearing at present. The proband's maternal grandmother exhibited mild HL since the age of 50. Using whole‐exome sequencing (WES), we identified a donor splice‐site variant (NM_014332.2: c.132 + 1G>A) in the SMPX gene in the proband. The mother and maternal grandmother were both carriers, which suggested a X‐linked inheritance of the condition in the family. RT‐PCR and Sanger sequencing revealed that four alternative splice pairs within intron 3 have led to four aberrant RNAs transcripts, including two non‐canonical splice‐pairs (GC‐AG and CT‐AG). The variant generated a novel frameshift variant, creating a premature termination codon (PTC) upstream of a newly formed splice site (p.Met45Glyfs*16). SMPX mRNA expression assay showed that the PTC has caused degradation of mRNA via nonsense‐mediated mRNA decay (NMD). Conclusion This is the first study to report a SMPX (DFNX4) splicing variant in a Chinese family. These findings, especially congenital deafness, contributed to existing knowledge regarding the genotypic and phenotypic spectrum of SMPX‐associated hearing loss.
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Affiliation(s)
- Yuan Lv
- Key Laboratory of Maternal-Fetal Medicine of Liaoning Province, Key Laboratory of Obstetrics and Gynecology of Higher Education of Liaoning Province, Liaoning Centre for Prenatal Diagnosis, Research Center of China Medical University Birth Cohort, Department of Gynecology & Obstetrics, Shengjing Hospital Affiliated to China Medical University, Shenyang, Liaoning, China
| | - Jia Gu
- Department of Otolaryngology, The First Hospital Affiliated to China Medical University, Shenyang, Liaoning, China
| | - Hao Qiu
- Basecare Medical Device Co., Ltd., Suzhou, Jiangsu, China
| | - Huan Li
- Key Laboratory of Maternal-Fetal Medicine of Liaoning Province, Key Laboratory of Obstetrics and Gynecology of Higher Education of Liaoning Province, Liaoning Centre for Prenatal Diagnosis, Research Center of China Medical University Birth Cohort, Department of Gynecology & Obstetrics, Shengjing Hospital Affiliated to China Medical University, Shenyang, Liaoning, China
| | - Zhitao Zhang
- Key Laboratory of Maternal-Fetal Medicine of Liaoning Province, Key Laboratory of Obstetrics and Gynecology of Higher Education of Liaoning Province, Liaoning Centre for Prenatal Diagnosis, Research Center of China Medical University Birth Cohort, Department of Gynecology & Obstetrics, Shengjing Hospital Affiliated to China Medical University, Shenyang, Liaoning, China
| | - Shaowei Yin
- Key Laboratory of Maternal-Fetal Medicine of Liaoning Province, Key Laboratory of Obstetrics and Gynecology of Higher Education of Liaoning Province, Liaoning Centre for Prenatal Diagnosis, Research Center of China Medical University Birth Cohort, Department of Gynecology & Obstetrics, Shengjing Hospital Affiliated to China Medical University, Shenyang, Liaoning, China
| | - Yan Mao
- Basecare Medical Device Co., Ltd., Suzhou, Jiangsu, China
| | - Lingyin Kong
- Basecare Medical Device Co., Ltd., Suzhou, Jiangsu, China
| | - Bo Liang
- State Key Laboratory of Microbial Metabolism, Joint International Research Laboratory of Metabolic and Developmental Sciences, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, China
| | - Hongkun Jiang
- Department of Pediatrics, The First Affiliated Hospital of China Medical University, Shenyang, Liaoning, China
| | - Caixia Liu
- Key Laboratory of Maternal-Fetal Medicine of Liaoning Province, Key Laboratory of Obstetrics and Gynecology of Higher Education of Liaoning Province, Liaoning Centre for Prenatal Diagnosis, Research Center of China Medical University Birth Cohort, Department of Gynecology & Obstetrics, Shengjing Hospital Affiliated to China Medical University, Shenyang, Liaoning, China
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17
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D'Aguillo C, Bressler S, Yan D, Mittal R, Fifer R, Blanton SH, Liu X. Genetic screening as an adjunct to universal newborn hearing screening: literature review and implications for non-congenital pre-lingual hearing loss. Int J Audiol 2019; 58:834-850. [PMID: 31264897 DOI: 10.1080/14992027.2019.1632499] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Objective: Universal newborn hearing screening (UNHS) uses otoacoustic emissions testing (OAE) and auditory brainstem response testing (ABR) to screen all newborn infants for hearing loss (HL), but may not identify infants with mild HL at birth or delayed onset HL. The purpose of this review is to examine the role of genetic screening to diagnose children with pre-lingual HL that is not detected at birth by determining the rate of children who pass UNHS but have a positive genetic screening. This includes a summary of the current UNHS and its limitations and a review of genetic mutations and screening technologies used to detect patients with an increased risk of undiagnosed pre-lingual HL.Design: Literature review of studies that compare UNHS with concurrent genetic screening.Study sample: Infants and children with HLResults: Sixteen studies were included encompassing 137,895 infants. Pathogenic mutations were detected in 8.66% of patients. In total, 545 patients passed the UNHS but had a positive genetic screening. The average percentage of patients who passed UNHS but had a positive genetic screening was 1.4%.Conclusions: This review demonstrates the positive impact of concurrent genetic screening with UNHS to identify patients with pre-lingual HL.
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Affiliation(s)
- Christine D'Aguillo
- Department of Otolaryngology, University of Miami Miller School of Medicine, Miami, FL, USA
| | - Sara Bressler
- Department of Otolaryngology, University of Miami Miller School of Medicine, Miami, FL, USA
| | - Denise Yan
- Department of Otolaryngology, University of Miami Miller School of Medicine, Miami, FL, USA
| | - Rahul Mittal
- Department of Otolaryngology, University of Miami Miller School of Medicine, Miami, FL, USA
| | - Robert Fifer
- Department of Pediatrics, University of Miami Miller School of Medicine, Miami, FL, USA
| | - Susan H Blanton
- Department of Otolaryngology, University of Miami Miller School of Medicine, Miami, FL, USA.,Department of Human Genetics, Dr. John T. Macdonald Foundation, Miami, FL, USA.,John P Hussman Institute for Human Genomics, University of Miami Miller School of Medicine, Miami, FL, USA
| | - Xuezhong Liu
- Department of Otolaryngology, University of Miami Miller School of Medicine, Miami, FL, USA.,Department of Pediatrics, University of Miami Miller School of Medicine, Miami, FL, USA.,Department of Human Genetics, Dr. John T. Macdonald Foundation, Miami, FL, USA.,John P Hussman Institute for Human Genomics, University of Miami Miller School of Medicine, Miami, FL, USA.,Tsinghua University School of Medicine, Beijing, PR China
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18
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DeSmidt AA, Zou B, Grati M, Yan D, Mittal R, Yao Q, Richmond MT, Denyer S, Liu XZ, Lu Z. Zebrafish Model for Nonsyndromic X-Linked Sensorineural Deafness, DFNX1. Anat Rec (Hoboken) 2019; 303:544-555. [PMID: 30874365 DOI: 10.1002/ar.24115] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2018] [Revised: 08/23/2018] [Accepted: 09/05/2018] [Indexed: 11/08/2022]
Abstract
Hereditary deafness is often a neurosensory disorder and affects the quality of life of humans. Only three X-linked genes (POU class 3 homeobox 4 (POU3F4), phosphoribosyl pyrophosphate synthetase 1 (PRPS1), and small muscle protein X-linked (SMPX)) are known to be involved in nonsyndromic hearing loss. Four PRPS1 missense mutations have been found to associate with X-linked nonsyndromic sensorineural deafness (DFNX1/DFN2) in humans. However, a causative relationship between PRPS1 mutations and hearing loss in humans has not been well studied in any animal model. Phosphoribosyl pyrophosphate synthetase 1 (PRS-I) is highly conserved in vertebrate taxa. In this study, we used the zebrafish as a model to investigate the auditory role of zebrafish orthologs (prps1a and prps1b) of the human PRPS1 gene with whole mount in situ hybridization, reverse transcription polymerase chain reaction, phenotypic screening, confocal imaging, and electrophysiological methods. We found that both prps1a and prps1b genes were expressed in the inner ear of zebrafish. Splice-blocking antisense morpholino oligonucleotides (MO1 and MO2) caused exon-2 skip and intron-2 retention of prps1a and exon-2 skip and intron-1 retention of prps1b to knock down functions of the genes, respectively. MO1 and MO2 morphants had smaller otic vesicles and otoliths, fewer inner ear hair cells, and lower microphonic response amplitude and sensitivity than control zebrafish. Therefore, knockdown of either prps1a or prps1b resulted in significant sensorineural hearing loss in zebrafish. We conclude that the prps1 genes are essential for hearing in zebrafish, which has the potential to help us understand the biology of human deafness DFNX1/DFN2. Anat Rec, 303:544-555, 2020. © 2019 American Association for Anatomy.
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Affiliation(s)
| | - Bing Zou
- Department of Biology, University of Miami, Coral Gables, Florida.,Department of Otolaryngology, University of Miami Miller School of Medicine, Miami, Florida
| | - M'hamed Grati
- Department of Otolaryngology, University of Miami Miller School of Medicine, Miami, Florida
| | - Denise Yan
- Department of Otolaryngology, University of Miami Miller School of Medicine, Miami, Florida
| | - Rahul Mittal
- Department of Otolaryngology, University of Miami Miller School of Medicine, Miami, Florida
| | - Qi Yao
- Department of Biology, University of Miami, Coral Gables, Florida.,Department of Otolaryngology, University of Miami Miller School of Medicine, Miami, Florida
| | | | - Steven Denyer
- Department of Biology, University of Miami, Coral Gables, Florida
| | - Xue Zhong Liu
- Department of Otolaryngology, University of Miami Miller School of Medicine, Miami, Florida.,Department of Otolaryngology, Xiangya Hospital, Central South University, Changsha, People's Republic of China
| | - Zhongmin Lu
- Department of Biology, University of Miami, Coral Gables, Florida.,Department of Otolaryngology, University of Miami Miller School of Medicine, Miami, Florida.,Neuroscience Program, University of Miami, Miami, Florida.,International Center for Marine Studies, Shanghai Ocean University, Shanghai, People's Republic of China
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19
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Carpena NT, Lee MY. Genetic Hearing Loss and Gene Therapy. Genomics Inform 2018; 16:e20. [PMID: 30602081 PMCID: PMC6440668 DOI: 10.5808/gi.2018.16.4.e20] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2018] [Accepted: 12/04/2018] [Indexed: 12/15/2022] Open
Abstract
Genetic hearing loss crosses almost all the categories of hearing loss which includes the following: conductive, sensory, and neural; syndromic and nonsyndromic; congenital, progressive, and adult onset; high-frequency, low-frequency, or mixed frequency; mild or profound; and recessive, dominant, or sex-linked. Genes play a role in almost half of all cases of hearing loss but effective treatment options are very limited. Genetic hearing loss is considered to be extremely genetically heterogeneous. The advancements in genomics have been instrumental to the identification of more than 6,000 causative variants in more than 150 genes causing hearing loss. Identification of genes for hearing impairment provides an increased insight into the normal development and function of cells in the auditory system. These defective genes will ultimately be important therapeutic targets. However, the auditory system is extremely complex which requires tremendous advances in gene therapy including gene vectors, routes of administration, and therapeutic approaches. This review summarizes and discusses recent advances in elucidating the genomics of genetic hearing loss and technologies aimed at developing a gene therapy that may become a treatment option for in the near future.
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Affiliation(s)
- Nathanial T Carpena
- Department of Otolaryngology-Head and Neck Surgery, Dankook University College of Medicine, Cheonan 31116, Korea
| | - Min Young Lee
- Department of Otolaryngology-Head and Neck Surgery, Dankook University College of Medicine, Cheonan 31116, Korea.,Beckman Laser Institute Korea, Dankook University, Cheonan 31116, Korea
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20
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Gao S, Jiang Y, Wang G, Yuan Y, Huang S, Gao X, Li X, Zhang D, Wu J, Ji X, Deng T, Wang L, Kang D, Dai P. Skewed X-chromosome inactivation and next-generation sequencing to identify a novel SMPX variants associated with X-linked hearing loss in a Chinese family. Int J Pediatr Otorhinolaryngol 2018; 113:88-93. [PMID: 30174017 DOI: 10.1016/j.ijporl.2018.07.022] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/23/2018] [Revised: 07/12/2018] [Accepted: 07/13/2018] [Indexed: 10/28/2022]
Abstract
OBJECTIVE Hereditary nonsyndromic hearing loss is extremely heterogeneous and an X-linked form accounts for 1-5% of all cases. The aim of this study was to identify the pathogenic variants in a nonsyndromic X-linked dominant hearing loss family, and explain the reason of different hearing phenotype in hearing between the two sisters with the same variant. METHODS Targeted gene capture and next-generation sequencing were used to study the genetic cause. What's more, methylation differences among the androgen receptor genes were used to investigate whether the different hearing levels of the two sisters is related to X-chromosome inactivation (Xi). RESULTS We identified SMPX c.29insA (p.Asn10Lysfs*3) as the novel variant causing deafness. The skewed X-chromosome inactivation was relevant to the hearing difference between the two sisters. CONCLUSION Targeted gene capture and NGS is an efficient way to identify pathogenic variants in genes. Analysis of X-chromosome inactivation is beneficial to the diagnosis and genetic counseling of X-linked dominant hearing loss families.
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Affiliation(s)
- Song Gao
- Department of Otolaryngology-Head and Neck Surgery, Chinese PLA General Hospital, Beijing, China; Department of Otolaryngology, The 175th Hospital of PLA, South-East Hospital Affiliated to Xiamen University, Zhangzhou, China
| | - Yi Jiang
- Department of Otolaryngology, Fujian Medical University ShengLi Clinical College, Fujian Provincial Hospital, Fuzhou, China
| | - Guojian Wang
- Department of Otolaryngology-Head and Neck Surgery, Chinese PLA General Hospital, Beijing, China
| | - Yongyi Yuan
- Department of Otolaryngology-Head and Neck Surgery, Chinese PLA General Hospital, Beijing, China
| | - Shasha Huang
- Department of Otolaryngology-Head and Neck Surgery, Chinese PLA General Hospital, Beijing, China
| | - Xue Gao
- Department of Otolaryngology, The General Hospital of the PLA Rocket Force, Beijing, China
| | - Xiaohong Li
- Department of Otolaryngology-Head and Neck Surgery, Chinese PLA General Hospital, Beijing, China
| | - Dejun Zhang
- Department of Otolaryngology-Head and Neck Surgery, Chinese PLA General Hospital, Beijing, China
| | - Jian Wu
- MyGenostics Inc., Beijing, China
| | | | - Tao Deng
- Beijing Capital Bio Independent Clinical Laboratory, Beijing, PR China
| | - Ligang Wang
- Beijing Capital Bio Independent Clinical Laboratory, Beijing, PR China
| | - Dongyang Kang
- Department of Otolaryngology-Head and Neck Surgery, Chinese PLA General Hospital, Beijing, China
| | - Pu Dai
- Department of Otolaryngology-Head and Neck Surgery, Chinese PLA General Hospital, Beijing, China.
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21
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Su Y, Gao X, Huang SS, Mao JN, Huang BQ, Zhao JD, Kang DY, Zhang X, Dai P. Clinical and molecular characterization of POU3F4 mutations in multiple DFNX2 Chinese families. BMC MEDICAL GENETICS 2018; 19:157. [PMID: 30176854 PMCID: PMC6122742 DOI: 10.1186/s12881-018-0630-9] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/06/2017] [Accepted: 06/21/2018] [Indexed: 02/07/2023]
Abstract
Background Many X-linked non-syndromic hearing loss (HL) cases are caused by various mutations in the POU domain class 3 transcription factor 4 (POU3F4) gene. This study aimed to identify allelic variants of this gene in two Chinese families displaying X-linked inheritance deafness-2 (DFNX2) and one sporadic case with indefinite inheritance pattern. Methods Direct DNA sequencing of the POU3F4 gene was performed in these families and in 100 Chinese individuals with normal hearing. Results There are characteristic imaging findings in DFNX2 Chinese families with POU3F4 mutations. The temporal bone computed tomography (CT) images of patients with DFNX2 are characterized by a thickened stapes footplate, hypoplasia of the cochlear base, absence of the bony modiolus, and dilated internal acoustic meatus (IAM) as well as by abnormally wide communication between the IAM and the basal turn of the cochlea. We identified three causative mutations in POU3F4 for three probands and their extended families. In family 1468, we observed a novel deletion mutation, c.973delT, which is predicted to result in a p.Trp325Gly amino acid frameshift. In family 2741, the mutation c.927delCTC was identified, which is predicted to result in the deletion of serine at position 310. In both families, the mutations were located in the POU homeodomain and are predicted to truncate the C-terminus of the POU domain. In the third family, a novel de novo transversion mutation (c.669 T > A) was identified in a 5-year-old boy that resulted in a nonsense mutation (p.Tyr223*). The mutation created a new stop codon and is predicted to result in a truncated POU3F4 protein. Conclusions Based on characteristic radiological findings and clinical features, POU3F4 gene mutation analysis will increase the success rate of stapes operations and cochlear implantations, and improve molecular diagnosis, genetic counseling, and knowledge of the molecular epidemiology of HL among patients with DFNX2.
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Affiliation(s)
- Yu Su
- Department of Otorhinolaryngology, Head and Neck Surgery, PLA General Hospital, Beijing, 100853, People's Republic of China.,Department of Otorhinolaryngology, Hainan Branch of PLA General Hospital, Sanya, 572000, People's Republic of China
| | - Xue Gao
- Department of Otorhinolaryngology, Head and Neck Surgery, PLA General Hospital, Beijing, 100853, People's Republic of China.,Department of Otolaryngology, The General Hospital of the PLA Rocket Force, 16# Xi Wai Da Jie, Beijing, 100088, People's Republic of China
| | - Sha-Sha Huang
- Department of Otorhinolaryngology, Head and Neck Surgery, PLA General Hospital, Beijing, 100853, People's Republic of China
| | - Jing-Ning Mao
- Department of Medical Imaging, PLA 307 Hospital, Beijing, 100074, People's Republic of China
| | - Bang-Qing Huang
- Department of Otorhinolaryngology, Hainan Branch of PLA General Hospital, Sanya, 572000, People's Republic of China
| | - Jian-Dong Zhao
- Department of Otorhinolaryngology, Head and Neck Surgery, PLA General Hospital, Beijing, 100853, People's Republic of China
| | - Dong-Yang Kang
- Department of Otorhinolaryngology, Head and Neck Surgery, PLA General Hospital, Beijing, 100853, People's Republic of China
| | - Xin Zhang
- Department of Otorhinolaryngology, Head and Neck Surgery, PLA General Hospital, Beijing, 100853, People's Republic of China
| | - Pu Dai
- Department of Otorhinolaryngology, Head and Neck Surgery, PLA General Hospital, Beijing, 100853, People's Republic of China.
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22
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Balta B, Gundogdu R, Erdogan M, Alisik M, Kiraz A, Ozcan I, Erel O. Decreased disulphide/thiol ratio in patients with autosomal recessive non-syndromic hearing loss. Int J Pediatr Otorhinolaryngol 2018; 112:188-192. [PMID: 30055731 DOI: 10.1016/j.ijporl.2018.07.014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/12/2018] [Revised: 07/05/2018] [Accepted: 07/09/2018] [Indexed: 11/26/2022]
Abstract
INTRODUCTION Oxidative stress plays a key role in the formation of age-related, noise-induced and drug-induced hearing loss. Thiols are organic compounds which can react with free radicals to protect against tissue and cell damage caused by reactive oxygen. There are no studies in literature on the association between autosomal recessive non-syndromic hearing loss(ARNSHL) including GJB2 and non-GJB2 mutations and thiol-disulphide balance. In this study, we aim to assess whether thiol-disulphide balance is disrupted in patients with ARNSHL. METHODS Thirty-one ARNSHL patients and thirty-one healthy controls were included in this study. Patients whose parents were first degree cousins and who had at least two congenital hearing loss in the same family were included in the study. Audiological tests included air - bone pure tone audiometry and auditory brain stem response. GJB2 gene analysis was performed using sanger sequence method. Tests of thiol/disulphide homeostasis were conducted using the automated spectrophotometric method. We first investigated whether there was a significant difference between ARNSHL patients and healthy controls. Then, in order to determine the differential effect of the GJB2 gene mutations and non-GJB2 gene mutations on the thiol-disulphide balance, subjects were divided into three groups: Group 1 included patients with GJB2 mutations; Group 2 included patients with non-GJB2 mutations; Group 3 included healthy subjects. RESULTS Patients with ARNSHL had significantly higher native thiol (411.6 ± 54.3 μmol/l vs. 368.0 ± 64.3 μmol/l, p = 0.006), total thiol levels (440.3 ± 56.2 μmol/l vs. 402.4 ± 65.9 μmol/l, p = 0.018), and lower disulphide levels (14.3 ± 5.7 μmol/l) vs. (17.1 ± 4.9 μmol/l), (p = 0.043) compared to the control group. Moreover, disulphide /native thiol (p < 0.001) and disulphide/total thiol (p < 0.001) were also detected lower in the ARNSHL group compared to the control group. Thiol-disulphide hemostasis parameters between all three groups showed that the native thiol and total thiol were increased in the Group 1 and Group 2. The disulphide levels decreased in Group 1 and 2, although not statistically significant. CONCLUSION It was shown that thiol levels increased and disulphide levels decreased in patients with autosomal recessive non-syndromic hearing loss. It also may suggest that there is a reverse association between ARNSHL and oxidative stress. Further studies are needed on whether or not ARNSHL cause oxidative stress limited to the inner ear and cochlea.
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Affiliation(s)
- Burhan Balta
- Department of Medical Genetics, Kayseri Training and Research Hospital, Kayseri, Turkey.
| | - Ramazan Gundogdu
- Department of Otorhinolaryngology, Kayseri Training and Research Hospital, Kayseri, Turkey.
| | - Murat Erdogan
- Department of Medical Genetics, Kayseri Training and Research Hospital, Kayseri, Turkey.
| | - Murat Alisik
- Department of Biochemistry, Yıldırım Beyazıd University, Ankara, Turkey.
| | - Aslihan Kiraz
- Department of Medical Genetics, Kayseri Training and Research Hospital, Kayseri, Turkey.
| | - Ibrahim Ozcan
- Department of Otorhinolaryngology, Kayseri Training and Research Hospital, Kayseri, Turkey.
| | - Ozcan Erel
- Department of Biochemistry, Yıldırım Beyazıd University, Ankara, Turkey.
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23
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Corvino V, Apisa P, Malesci R, Laria C, Auletta G, Franzé A. X-Linked Sensorineural Hearing Loss: A Literature Review. Curr Genomics 2018; 19:327-338. [PMID: 30065609 PMCID: PMC6030855 DOI: 10.2174/1389202919666171218163046] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2017] [Revised: 11/10/2017] [Accepted: 12/04/2017] [Indexed: 01/01/2023] Open
Abstract
Sensorineural hearing loss is a very diffuse pathology (about 1/1000 born) with several types of transmission. X-linked hearing loss accounts for approximately 1% - 2% of cases of non-syndromic forms, as well as for many syndromic forms. To date, six loci (DFNX1-6) and five genes (PRPS1 for DFNX1, POU3F4 for DFNX2, SMPX for DFNX4, AIFM1 for DFNX5 and COL4A6 for DFNX6) have been identified for X-linked non-syndromic hearing loss. For the syndromic forms, at least 15 genes have been identified, some of which are also implicated in non-syndromic forms. Moreover, some syndromic forms, presenting large chromosomal deletions, are associated with mental retardation too. This review presents an overview of the currently known genes related to X-linked hearing loss with the support of the most recent literature. It summarizes the genetics and clinical features of X-linked hearing loss to give information useful to realize a clear genetic counseling and an early diagnosis. It is important to get an early diagnosis of these diseases to decide the investigations to predict the evolution of the disease and the onset of any other future symptoms. This information will be clearly useful for choosing the best therapeutic strategy. In particular, regarding audiological aspects, this review highlights risks and benefits currently known in some cases for specific therapeutic intervention.
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Affiliation(s)
- Virginia Corvino
- Unit of Audiology, Department of Neurosciences, Reproductives and Odontostomatologic Sciences, University of Naples “Federico II”, Naples, Italy
| | - Pasqualina Apisa
- Unit of Audiology, Department of Neurosciences, Reproductives and Odontostomatologic Sciences, University of Naples “Federico II”, Naples, Italy
| | - Rita Malesci
- Unit of Audiology, Department of Neurosciences, Reproductives and Odontostomatologic Sciences, University of Naples “Federico II”, Naples, Italy
| | - Carla Laria
- Unit of Audiology, Department of Neurosciences, Reproductives and Odontostomatologic Sciences, University of Naples “Federico II”, Naples, Italy
| | - Gennaro Auletta
- Unit of Audiology, Department of Neurosciences, Reproductives and Odontostomatologic Sciences, University of Naples “Federico II”, Naples, Italy
| | - Annamaria Franzé
- Unit of Audiology, Department of Neurosciences, Reproductives and Odontostomatologic Sciences, University of Naples “Federico II”, Naples, Italy
- CEINGE Biotecnologie Avanzate, Naples, Italy
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24
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Wesdorp M, Murillo-Cuesta S, Peters T, Celaya AM, Oonk A, Schraders M, Oostrik J, Gomez-Rosas E, Beynon AJ, Hartel BP, Okkersen K, Koenen HJPM, Weeda J, Lelieveld S, Voermans NC, Joosten I, Hoyng CB, Lichtner P, Kunst HPM, Feenstra I, de Bruijn SE, Admiraal RJC, Yntema HG, van Wijk E, Del Castillo I, Serra P, Varela-Nieto I, Pennings RJE, Kremer H. MPZL2, Encoding the Epithelial Junctional Protein Myelin Protein Zero-like 2, Is Essential for Hearing in Man and Mouse. Am J Hum Genet 2018; 103:74-88. [PMID: 29961571 DOI: 10.1016/j.ajhg.2018.05.011] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2017] [Accepted: 05/25/2018] [Indexed: 02/01/2023] Open
Abstract
In a Dutch consanguineous family with recessively inherited nonsyndromic hearing impairment (HI), homozygosity mapping combined with whole-exome sequencing revealed a MPZL2 homozygous truncating variant, c.72del (p.Ile24Metfs∗22). By screening a cohort of phenotype-matched subjects and a cohort of HI subjects in whom WES had been performed previously, we identified two additional families with biallelic truncating variants of MPZL2. Affected individuals demonstrated symmetric, progressive, mild to moderate sensorineural HI. Onset of HI was in the first decade, and high-frequency hearing was more severely affected. There was no vestibular involvement. MPZL2 encodes myelin protein zero-like 2, an adhesion molecule that mediates epithelial cell-cell interactions in several (developing) tissues. Involvement of MPZL2 in hearing was confirmed by audiometric evaluation of Mpzl2-mutant mice. These displayed early-onset progressive sensorineural HI that was more pronounced in the high frequencies. Histological analysis of adult mutant mice demonstrated an altered organization of outer hair cells and supporting cells and degeneration of the organ of Corti. In addition, we observed mild degeneration of spiral ganglion neurons, and this degeneration was most pronounced at the cochlear base. Although MPZL2 is known to function in cell adhesion in several tissues, no phenotypes other than HI were found to be associated with MPZL2 defects. This indicates that MPZL2 has a unique function in the inner ear. The present study suggests that deleterious variants of Mplz2/MPZL2 affect adhesion of the inner-ear epithelium and result in loss of structural integrity of the organ of Corti and progressive degeneration of hair cells, supporting cells, and spiral ganglion neurons.
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Affiliation(s)
- Mieke Wesdorp
- Hearing and Genes Division, Department of Otorhinolaryngology, Radboud University Medical Center, 6500 HB Nijmegen, the Netherlands; The Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, 6500 HB Nijmegen, the Netherlands; Donders Institute for Brain, Cognition and Behavior, Radboud University Medical Center, 6500 HB Nijmegen, the Netherlands
| | - Silvia Murillo-Cuesta
- Institute of Biomedical Research "Alberto Sols," Spanish National Research Council-Autonomous University of Madrid, 28029 Madrid, Spain; Center for Biomedical Network Research in Rare Diseases, Institute of Health Carlos III, 28029 Madrid, Spain; Hospital La Paz Institute for Health Research, 28029 Madrid, Spain
| | - Theo Peters
- Hearing and Genes Division, Department of Otorhinolaryngology, Radboud University Medical Center, 6500 HB Nijmegen, the Netherlands; Donders Institute for Brain, Cognition and Behavior, Radboud University Medical Center, 6500 HB Nijmegen, the Netherlands
| | - Adelaida M Celaya
- Institute of Biomedical Research "Alberto Sols," Spanish National Research Council-Autonomous University of Madrid, 28029 Madrid, Spain; Center for Biomedical Network Research in Rare Diseases, Institute of Health Carlos III, 28029 Madrid, Spain
| | - Anne Oonk
- Hearing and Genes Division, Department of Otorhinolaryngology, Radboud University Medical Center, 6500 HB Nijmegen, the Netherlands
| | - Margit Schraders
- Hearing and Genes Division, Department of Otorhinolaryngology, Radboud University Medical Center, 6500 HB Nijmegen, the Netherlands; Donders Institute for Brain, Cognition and Behavior, Radboud University Medical Center, 6500 HB Nijmegen, the Netherlands
| | - Jaap Oostrik
- Hearing and Genes Division, Department of Otorhinolaryngology, Radboud University Medical Center, 6500 HB Nijmegen, the Netherlands; Donders Institute for Brain, Cognition and Behavior, Radboud University Medical Center, 6500 HB Nijmegen, the Netherlands
| | - Elena Gomez-Rosas
- Center for Biomedical Network Research in Rare Diseases, Institute of Health Carlos III, 28029 Madrid, Spain; Servicio de Genetica, Hospital Universitario Ramon y Cajal, Instituto Ramón y Cajal de Investigación Sanitaria, Madrid, Spain
| | - Andy J Beynon
- Hearing and Genes Division, Department of Otorhinolaryngology, Radboud University Medical Center, 6500 HB Nijmegen, the Netherlands
| | - Bas P Hartel
- Hearing and Genes Division, Department of Otorhinolaryngology, Radboud University Medical Center, 6500 HB Nijmegen, the Netherlands; Donders Institute for Brain, Cognition and Behavior, Radboud University Medical Center, 6500 HB Nijmegen, the Netherlands
| | - Kees Okkersen
- Donders Institute for Brain, Cognition and Behavior, Radboud University Medical Center, 6500 HB Nijmegen, the Netherlands; Department of Neurology, Radboud University Medical Center, 6500 HB Nijmegen, the Netherlands
| | - Hans J P M Koenen
- Laboratory of Medical Immunology, Department of Laboratory Medicine, Radboud University Medical Center, 6500 HB Nijmegen, the Netherlands
| | - Jack Weeda
- Department of Ophthalmology, Radboud University Medical Center, 6500 HB Nijmegen, the Netherlands
| | - Stefan Lelieveld
- The Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, 6500 HB Nijmegen, the Netherlands; Department of Human Genetics, Radboud University Medical Center, 6500 HB Nijmegen, the Netherlands
| | - Nicol C Voermans
- Donders Institute for Brain, Cognition and Behavior, Radboud University Medical Center, 6500 HB Nijmegen, the Netherlands; Department of Neurology, Radboud University Medical Center, 6500 HB Nijmegen, the Netherlands
| | - Irma Joosten
- Laboratory of Medical Immunology, Department of Laboratory Medicine, Radboud University Medical Center, 6500 HB Nijmegen, the Netherlands
| | - Carel B Hoyng
- Donders Institute for Brain, Cognition and Behavior, Radboud University Medical Center, 6500 HB Nijmegen, the Netherlands; Department of Ophthalmology, Radboud University Medical Center, 6500 HB Nijmegen, the Netherlands
| | - Peter Lichtner
- Institute of Human Genetics, Helmholtz Zentrum München, Neuherberg, Germany
| | - Henricus P M Kunst
- Hearing and Genes Division, Department of Otorhinolaryngology, Radboud University Medical Center, 6500 HB Nijmegen, the Netherlands; Radboud Institute of Health Sciences, Radboud University Medical Center, 6500 HB Nijmegen, the Netherlands
| | - Ilse Feenstra
- Department of Human Genetics, Radboud University Medical Center, 6500 HB Nijmegen, the Netherlands
| | - Suzanne E de Bruijn
- Department of Human Genetics, Radboud University Medical Center, 6500 HB Nijmegen, the Netherlands
| | - Ronald J C Admiraal
- Hearing and Genes Division, Department of Otorhinolaryngology, Radboud University Medical Center, 6500 HB Nijmegen, the Netherlands
| | - Helger G Yntema
- Department of Human Genetics, Radboud University Medical Center, 6500 HB Nijmegen, the Netherlands
| | - Erwin van Wijk
- Hearing and Genes Division, Department of Otorhinolaryngology, Radboud University Medical Center, 6500 HB Nijmegen, the Netherlands; Donders Institute for Brain, Cognition and Behavior, Radboud University Medical Center, 6500 HB Nijmegen, the Netherlands
| | - Ignacio Del Castillo
- Center for Biomedical Network Research in Rare Diseases, Institute of Health Carlos III, 28029 Madrid, Spain; Servicio de Genetica, Hospital Universitario Ramon y Cajal, Instituto Ramón y Cajal de Investigación Sanitaria, Madrid, Spain
| | - Pau Serra
- Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), 08036 Barcelona, Spain
| | - Isabel Varela-Nieto
- Institute of Biomedical Research "Alberto Sols," Spanish National Research Council-Autonomous University of Madrid, 28029 Madrid, Spain; Center for Biomedical Network Research in Rare Diseases, Institute of Health Carlos III, 28029 Madrid, Spain; Hospital La Paz Institute for Health Research, 28029 Madrid, Spain
| | - Ronald J E Pennings
- Hearing and Genes Division, Department of Otorhinolaryngology, Radboud University Medical Center, 6500 HB Nijmegen, the Netherlands; Donders Institute for Brain, Cognition and Behavior, Radboud University Medical Center, 6500 HB Nijmegen, the Netherlands
| | - Hannie Kremer
- Hearing and Genes Division, Department of Otorhinolaryngology, Radboud University Medical Center, 6500 HB Nijmegen, the Netherlands; Donders Institute for Brain, Cognition and Behavior, Radboud University Medical Center, 6500 HB Nijmegen, the Netherlands; Department of Human Genetics, Radboud University Medical Center, 6500 HB Nijmegen, the Netherlands.
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25
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Sheppard S, Biswas S, Li MH, Jayaraman V, Slack I, Romasko EJ, Sasson A, Brunton J, Rajagopalan R, Sarmady M, Abrudan JL, Jairam S, DeChene ET, Ying X, Choi J, Wilkens A, Raible SE, Scarano MI, Santani A, Pennington JW, Luo M, Conlin LK, Devkota B, Dulik MC, Spinner NB, Krantz ID. Utility and limitations of exome sequencing as a genetic diagnostic tool for children with hearing loss. Genet Med 2018; 20:1663-1676. [PMID: 29907799 PMCID: PMC6295269 DOI: 10.1038/s41436-018-0004-x] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2017] [Accepted: 03/20/2018] [Indexed: 11/09/2022] Open
Abstract
PURPOSE Hearing loss (HL) is the most common sensory disorder in children. Prompt molecular diagnosis may guide screening and management, especially in syndromic cases when HL is the single presenting feature. Exome sequencing (ES) is an appealing diagnostic tool for HL as the genetic causes are highly heterogeneous. METHODS ES was performed on a prospective cohort of 43 probands with HL. Sequence data were analyzed for primary and secondary findings. Capture and coverage analysis was performed for genes and variants associated with HL. RESULTS The diagnostic rate using ES was 37.2%, compared with 15.8% for the clinical HL panel. Secondary findings were discovered in three patients. For 247 genes associated with HL, 94.7% of the exons were targeted for capture and 81.7% of these exons were covered at 20× or greater. Further analysis of 454 randomly selected HL-associated variants showed that 89% were targeted for capture and 75% were covered at a read depth of at least 20×. CONCLUSION ES has an improved yield compared with clinical testing and may capture diagnoses not initially considered due to subtle clinical phenotypes. Technical challenges were identified, including inadequate capture and coverage of HL genes. Additional considerations of ES include secondary findings, cost, and turnaround time.
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Affiliation(s)
- Sarah Sheppard
- Department of Pediatrics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA.,Division of Human Genetics, The Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Sawona Biswas
- Department of Pathology and Laboratory Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA.,Division of Genomic Diagnostics, The Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Mindy H Li
- Division of Genetics, Department of Pediatrics, Rush University Medical Center, Chicago, IL, USA
| | - Vijayakumar Jayaraman
- Division of Human Genetics, The Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Ian Slack
- Department of Pediatrics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Edward J Romasko
- Department of Pathology and Laboratory Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA.,Division of Genomic Diagnostics, The Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Ariella Sasson
- Department of Biomedical and Health Informatics, The Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Joshua Brunton
- Division of Human Genetics, The Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Ramakrishnan Rajagopalan
- Department of Pathology and Laboratory Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA.,Division of Genomic Diagnostics, The Children's Hospital of Philadelphia, Philadelphia, PA, USA.,Department of Biomedical and Health Informatics, The Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Mahdi Sarmady
- Department of Pathology and Laboratory Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA.,Division of Genomic Diagnostics, The Children's Hospital of Philadelphia, Philadelphia, PA, USA.,Department of Biomedical and Health Informatics, The Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Jenica L Abrudan
- Department of Pediatrics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA.,Division of Human Genetics, The Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Sowmya Jairam
- Department of Pathology and Laboratory Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA.,Division of Genomic Diagnostics, The Children's Hospital of Philadelphia, Philadelphia, PA, USA.,Department of Pathology, Memorial Sloan Kettering Cancer Center, New York, NY, USA
| | - Elizabeth T DeChene
- Division of Genomic Diagnostics, The Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Xiahoan Ying
- Division of Human Genetics, The Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Jiwon Choi
- Division of Human Genetics, The Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Alisha Wilkens
- Division of Human Genetics, The Children's Hospital of Philadelphia, Philadelphia, PA, USA.,Division of Genomic Diagnostics, The Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Sarah E Raible
- Division of Human Genetics, The Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Maria I Scarano
- Division of Genetics, Cooper University Health Care, Camden, NY, USA
| | - Avni Santani
- Department of Pathology and Laboratory Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA.,Division of Genomic Diagnostics, The Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Jeffrey W Pennington
- Department of Biomedical and Health Informatics, The Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Minjie Luo
- Department of Pathology and Laboratory Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA.,Division of Genomic Diagnostics, The Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Laura K Conlin
- Department of Pathology and Laboratory Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA.,Division of Genomic Diagnostics, The Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Batsal Devkota
- Department of Biomedical and Health Informatics, The Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Matthew C Dulik
- Department of Pathology and Laboratory Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA.,Division of Genomic Diagnostics, The Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Nancy B Spinner
- Department of Pathology and Laboratory Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA.,Division of Genomic Diagnostics, The Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Ian D Krantz
- Department of Pediatrics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA. .,Division of Human Genetics, The Children's Hospital of Philadelphia, Philadelphia, PA, USA.
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26
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A novel mutation in the SMPX gene associated with X-linked nonsyndromic sensorineural hearing loss in a Chinese family. J Hum Genet 2018; 63:723-730. [PMID: 29559740 DOI: 10.1038/s10038-018-0443-x] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2017] [Revised: 02/05/2018] [Accepted: 03/01/2018] [Indexed: 12/19/2022]
Abstract
X-linked inheritance is very rare and is estimated to account for only 1-5% of all nonsyndromic hearing loss cases. We found a multiplex family from China segregating with X-linked nonsyndromic hearing loss. After exclusive analysis of 10 common variations of three hearing loss-related genes, GJB2, mtDNA12srRNA and SLC26A4, a novel truncated variant of SMPX, c.87dupA (p.Gly30Argfs*12) (NCBI ClinVar Submission ID: SUB3136126), was identified by whole-exome sequencing. This variant was co-segregated with hearing loss in the entire family and was absent in 576 unrelated ethnically and geographically matched controls. We also detected a single nucleotide variation in two male controls with normal hearing, SMPX c.55A>G (p.Asn19Asp), which has been annotated as a rare variant in the Single Nucleotide Polymorphism (dbSNP) (rs759552778) and Exome Aggregation Consortium (ExAC) databases. This study has enriched the mutation spectrum of the SMPX gene.
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27
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Mittal R, Patel AP, Nguyen D, Pan DR, Jhaveri VM, Rudman JR, Dharmaraja A, Yan D, Feng Y, Chapagain P, Lee DJ, Blanton SH, Liu XZ. Genetic basis of hearing loss in Spanish, Hispanic and Latino populations. Gene 2018; 647:297-305. [PMID: 29331482 PMCID: PMC5806531 DOI: 10.1016/j.gene.2018.01.027] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2017] [Revised: 01/02/2018] [Accepted: 01/06/2018] [Indexed: 12/13/2022]
Abstract
Hearing loss (HL) is the most common neurosensory disorder affecting humans. The screening, prevention and treatment of HL require a better understanding of the underlying molecular mechanisms. Genetic predisposition is one of the most common factors that leads to HL. Most HL studies include few Spanish, Hispanic and Latino participants, leaving a critical gap in our understanding about the prevalence, impact, unmet health care needs, and genetic factors associated with hearing impairment among Spanish, Hispanic and Latino populations. The few studies which have been performed show that the gene variants commonly associated with HL in non-Spanish and non-Hispanic populations are infrequently responsible for hearing impairment in Spanish as well as Hispanic and Latino populations (hereafter referred to as Hispanic). To design effective screening tools to detect HL in Spanish and Hispanic populations, studies must be conducted to determine the gene variants that are most commonly associated with hearing impairment in this racial/ethnic group. In this review article, we summarize gene variants and loci associated with HL in Spanish and Hispanic populations. Identifying new genetic variants associated with HL in Spanish and Hispanic populations will pave the way to develop effective screening tools and therapeutic strategies for HL.
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Affiliation(s)
- Rahul Mittal
- Department of Otolaryngology, University of Miami Miller School of Medicine, Miami, FL, USA
| | - Amit P Patel
- Department of Otolaryngology, University of Miami Miller School of Medicine, Miami, FL, USA
| | - Desiree Nguyen
- Department of Otolaryngology, University of Miami Miller School of Medicine, Miami, FL, USA
| | - Debbie R Pan
- Department of Otolaryngology, University of Miami Miller School of Medicine, Miami, FL, USA
| | - Vasanti M Jhaveri
- Department of Otolaryngology, University of Miami Miller School of Medicine, Miami, FL, USA
| | - Jason R Rudman
- Department of Otolaryngology, University of Miami Miller School of Medicine, Miami, FL, USA
| | - Arjuna Dharmaraja
- Department of Otolaryngology, University of Miami Miller School of Medicine, Miami, FL, USA
| | - Denise Yan
- Department of Otolaryngology, University of Miami Miller School of Medicine, Miami, FL, USA
| | - Yong Feng
- Department of Otolaryngology, Xiangya Hospital, Central South University, Changsha, China
| | - Prem Chapagain
- Department of Physics and Biomolecular Sciences Institute, Florida International University, Miami, FL, USA
| | - David J Lee
- Department of Public Health Sciences, University of Miami Miller School of Medicine, Miami, FL, USA
| | - Susan H Blanton
- Department of Otolaryngology, University of Miami Miller School of Medicine, Miami, FL, USA; Dr. John T. Macdonald Foundation Department of Human Genetics and John P. Hussman Institute for Human Genetics, University of Miami Miller School of Medicine, Miami, FL 33136, USA
| | - Xue Zhong Liu
- Department of Otolaryngology, University of Miami Miller School of Medicine, Miami, FL, USA; Department of Otolaryngology, Xiangya Hospital, Central South University, Changsha, China; Tsinghua University School of Medicine, Beijing 10084, China; Dr. John T. Macdonald Foundation Department of Human Genetics and John P. Hussman Institute for Human Genetics, University of Miami Miller School of Medicine, Miami, FL 33136, USA.
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28
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Rudman JR, Mei C, Bressler SE, Blanton SH, Liu XZ. Precision medicine in hearing loss. J Genet Genomics 2018; 45:99-109. [PMID: 29500086 DOI: 10.1016/j.jgg.2018.02.004] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2017] [Revised: 02/12/2018] [Accepted: 02/12/2018] [Indexed: 11/26/2022]
Abstract
Precision medicine (PM) proposes customized medical care based on a patient's unique genome, biomarkers, environment and behaviors. Hearing loss (HL) is the most common sensorineural disorder worldwide and is frequently caused by a single genetic mutation. With recent advances in PM tools such as genetic sequencing and data analysis, the field of HL is ideally positioned to adopt the strategies of PM. Here, we review current and future applications of PM in HL as they relate to the four core qualities of PM (P4): predictive, personalized, patient-centered, and participatory. We then introduce a strategy for effective incorporation of HL PM into the design of future research studies, electronic medical records, and clinical practice to improve diagnostics, prognostics, and, ultimately, individualized patient treatment. Finally, specific anticipated ethical and economic concerns in this growing era of genomics-based HL treatment are discussed. By integrating PM principles into translational HL research and clinical practice, hearing specialists are uniquely positioned to effectively treat the heterogeneous causes and manifestations of HL on an individualized basis.
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Affiliation(s)
- Jason R Rudman
- Department of Otolaryngology, University of Miami Miller School of Medicine, Miami, FL 33136, USA
| | - Christine Mei
- Department of Otolaryngology, University of Miami Miller School of Medicine, Miami, FL 33136, USA
| | - Sara E Bressler
- Department of Otolaryngology, University of Miami Miller School of Medicine, Miami, FL 33136, USA
| | - Susan H Blanton
- Department of Otolaryngology, University of Miami Miller School of Medicine, Miami, FL 33136, USA; Dr. John T. Macdonald Foundation Department of Human Genetics, University of Miami Miller School of Medicine, Miami, FL 33136, USA; John P. Hussman Institute for Human Genomics, University of Miami Miller School of Medicine, Miami, FL 33136, USA
| | - Xue-Zhong Liu
- Department of Otolaryngology, University of Miami Miller School of Medicine, Miami, FL 33136, USA; Dr. John T. Macdonald Foundation Department of Human Genetics, University of Miami Miller School of Medicine, Miami, FL 33136, USA; John P. Hussman Institute for Human Genomics, University of Miami Miller School of Medicine, Miami, FL 33136, USA.
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Niu Z, Yan D, Bressler S, Mei L, Feng Y, Liu X. A novel splicing mutation in SMPX is linked to nonsyndromic progressive hearing loss. Int J Pediatr Otorhinolaryngol 2018; 104:47-50. [PMID: 29287879 DOI: 10.1016/j.ijporl.2017.10.040] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/16/2017] [Revised: 10/25/2017] [Accepted: 10/25/2017] [Indexed: 10/18/2022]
Abstract
OBJECTIVE X-linked nonsyndromic hearing impairment is the rarest form of genetic hearing loss and represents only a minor fraction of all cases. The aim of this study was to investigate the cause of X-linked nonsyndromic sensorineural hearing loss in a three-generation American family. METHODS Whole-exome sequencing and co-segregation analysis were used to identify disease-causing genes. RESULTS In this study, we described in detail the clinical characteristics of the family and identified a novel frameshift mutation creating a premature stop codon (c.133-1 G > A, p.(Gly45fs*36)) of SMPX. The loss-of-function mutation was co-segregated with the progressive hearing loss phenotype and was absent in 200 normal controls. CONCLUSIONS We report the first SMPX (DFNX4) mutation in a North American family. Our findings contribute to the existing genotypic and phenotypic spectrum of SMPX associated hearing loss. Furthermore, our data suggest that exome sequencing is promising in the genetic diagnosis of hearing loss.
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Affiliation(s)
- Zhijie Niu
- Department of Otolaryngology-Head and Neck Surgery, Xiangya Hospital, Central South University, Changsha 410008, China; Department of Otolaryngology, University of Miami Miller School of Medicine, Miami, FL 33136, USA
| | - Denise Yan
- Department of Otolaryngology, University of Miami Miller School of Medicine, Miami, FL 33136, USA
| | - Sara Bressler
- Department of Otolaryngology, University of Miami Miller School of Medicine, Miami, FL 33136, USA
| | - Lingyun Mei
- Department of Otolaryngology-Head and Neck Surgery, Xiangya Hospital, Central South University, Changsha 410008, China
| | - Yong Feng
- Department of Otolaryngology-Head and Neck Surgery, Xiangya Hospital, Central South University, Changsha 410008, China.
| | - Xuezhong Liu
- Department of Otolaryngology-Head and Neck Surgery, Xiangya Hospital, Central South University, Changsha 410008, China; Department of Otolaryngology, University of Miami Miller School of Medicine, Miami, FL 33136, USA.
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Niu Z, Feng Y, Mei L, Sun J, Wang X, Wang J, Hu Z, Dong Y, Chen H, He C, Liu Y, Cai X, Liu X, Jiang L. A novel frameshift mutation of SMPX causes a rare form of X-linked nonsyndromic hearing loss in a Chinese family. PLoS One 2017; 12:e0178384. [PMID: 28542515 PMCID: PMC5444825 DOI: 10.1371/journal.pone.0178384] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2017] [Accepted: 05/11/2017] [Indexed: 01/12/2023] Open
Abstract
X-linked hearing impairment is the rarest form of genetic hearing loss (HL) and represents only a minor fraction of all cases. The aim of this study was to investigate the cause of X-linked inherited sensorineural HL in a four-generation Chinese family. A novel duplication variant (c.217dupA, p.Ile73Asnfs*5) in SMPX was identified by whole-exome sequencing. The frameshift mutation predicted to result in the premature truncation of the SMPX protein was co-segregated with the HL phenotype and was absent in 295 normal controls. Subpopulation screening of the coding exons and flanking introns of SMPX was further performed for 338 Chinese patients with nonsydromic HL by Sanger sequencing, and another two potential causative substitutions (c.238C>A and c.55A>G) in SMPX were identified in additional sporadic cases of congenital deafness. Collectively, this study is the first to report the role of SMPX in Chinese population and identify a novel frameshift mutation in SMPX that causes not only nonsyndromic late-onset progressive HL, but also congenital hearing impairment. Our findings extend the mutation and phenotypic spectrum of the SMPX gene.
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Affiliation(s)
- Zhijie Niu
- Department of Otolaryngology-Head and Neck Surgery, Xiangya Hospital, Central South University, Changsha, PR China
- Key Laboratory of Otolaryngology Major Disease Research of Hunan Province, Changsha, PR China
- Department of Otolaryngology (D-48), University of Miami Miller School of Medicine, Miami, FL, United States of America
| | - Yong Feng
- Department of Otolaryngology-Head and Neck Surgery, Xiangya Hospital, Central South University, Changsha, PR China
- Key Laboratory of Otolaryngology Major Disease Research of Hunan Province, Changsha, PR China
- State Key Laboratory of Medical Genetics, Central South University, Changsha, PR China
| | - Lingyun Mei
- Department of Otolaryngology-Head and Neck Surgery, Xiangya Hospital, Central South University, Changsha, PR China
- Key Laboratory of Otolaryngology Major Disease Research of Hunan Province, Changsha, PR China
| | - Jie Sun
- Department of Otolaryngology-Head and Neck Surgery, Xiangya Hospital, Central South University, Changsha, PR China
- Key Laboratory of Otolaryngology Major Disease Research of Hunan Province, Changsha, PR China
| | - Xueping Wang
- Department of Otolaryngology-Head and Neck Surgery, Xiangya Hospital, Central South University, Changsha, PR China
- Key Laboratory of Otolaryngology Major Disease Research of Hunan Province, Changsha, PR China
| | - Juncheng Wang
- Department of Otolaryngology-Head and Neck Surgery, Xiangya Hospital, Central South University, Changsha, PR China
- Key Laboratory of Otolaryngology Major Disease Research of Hunan Province, Changsha, PR China
| | - Zhengmao Hu
- State Key Laboratory of Medical Genetics, Central South University, Changsha, PR China
| | - Yunpeng Dong
- Department of Otolaryngology (D-48), University of Miami Miller School of Medicine, Miami, FL, United States of America
| | - Hongsheng Chen
- Department of Otolaryngology-Head and Neck Surgery, Xiangya Hospital, Central South University, Changsha, PR China
- Key Laboratory of Otolaryngology Major Disease Research of Hunan Province, Changsha, PR China
| | - Chufeng He
- Department of Otolaryngology-Head and Neck Surgery, Xiangya Hospital, Central South University, Changsha, PR China
- Key Laboratory of Otolaryngology Major Disease Research of Hunan Province, Changsha, PR China
| | - Yalan Liu
- Department of Otolaryngology-Head and Neck Surgery, Xiangya Hospital, Central South University, Changsha, PR China
- Key Laboratory of Otolaryngology Major Disease Research of Hunan Province, Changsha, PR China
| | - Xinzhang Cai
- Department of Otolaryngology-Head and Neck Surgery, Xiangya Hospital, Central South University, Changsha, PR China
- Key Laboratory of Otolaryngology Major Disease Research of Hunan Province, Changsha, PR China
| | - Xuezhong Liu
- Department of Otolaryngology-Head and Neck Surgery, Xiangya Hospital, Central South University, Changsha, PR China
- Department of Otolaryngology (D-48), University of Miami Miller School of Medicine, Miami, FL, United States of America
| | - Lu Jiang
- Department of Otolaryngology-Head and Neck Surgery, Xiangya Hospital, Central South University, Changsha, PR China
- Key Laboratory of Otolaryngology Major Disease Research of Hunan Province, Changsha, PR China
- * E-mail:
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Cheng C, Guo L, Lu L, Xu X, Zhang S, Gao J, Waqas M, Zhu C, Chen Y, Zhang X, Xuan C, Gao X, Tang M, Chen F, Shi H, Li H, Chai R. Characterization of the Transcriptomes of Lgr5+ Hair Cell Progenitors and Lgr5- Supporting Cells in the Mouse Cochlea. Front Mol Neurosci 2017; 10:122. [PMID: 28491023 PMCID: PMC5405134 DOI: 10.3389/fnmol.2017.00122] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2017] [Accepted: 04/11/2017] [Indexed: 12/27/2022] Open
Abstract
Cochlear supporting cells (SCs) have been shown to be a promising resource for hair cell (HC) regeneration in the neonatal mouse cochlea. Previous studies have reported that Lgr5+ SCs can regenerate HCs both in vitro and in vivo and thus are considered to be inner ear progenitor cells. Lgr5+ progenitors are able to regenerate more HCs than Lgr5- SCs, and it is important to understand the mechanism behind the proliferation and HC regeneration of these progenitors. Here, we isolated Lgr5+ progenitors and Lgr5- SCs from Lgr5-EGFP-CreERT2/Sox2-CreERT2/Rosa26-tdTomato mice via flow cytometry. As expected, we found that Lgr5+ progenitors had significantly higher proliferation and HC regeneration ability than Lgr5- SCs. Next, we performed RNA-Seq to determine the gene expression profiles of Lgr5+ progenitors and Lgr5- SCs. We analyzed the genes that were enriched and differentially expressed in Lgr5+ progenitors and Lgr5- SCs, and we found 8 cell cycle genes, 9 transcription factors, and 24 cell signaling pathway genes that were uniquely expressed in one population but not the other. Last, we made a protein–protein interaction network to further analyze the role of these differentially expressed genes. In conclusion, we present a set of genes that might regulate the proliferation and HC regeneration ability of Lgr5+ progenitors, and these might serve as potential new therapeutic targets for HC regeneration.
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Affiliation(s)
- Cheng Cheng
- Key Laboratory for Developmental Genes and Human Disease, Ministry of Education, Institute of Life Sciences, Southeast UniversityNanjing, China.,Research Institute of OtolaryngologyNanjing, China.,Co-innovation Center of Neuroregeneration, Nantong UniversityNantong, China
| | - Luo Guo
- Department of Otorhinolaryngology, Affiliated Eye and ENT Hospital, State Key Laboratory of Medical Neurobiology, Fudan UniversityShanghai, China.,Key Laboratory of Hearing Medicine of National Health and Family Planning CommissionShanghai, China
| | - Ling Lu
- Department of Otolaryngology-Head and Neck Surgery, Nanjing Drum Tower Hospital, Nanjing University Medical SchoolNanjing, China.,Department of Otolaryngology-Head and Neck Surgery, Drum Tower Clinical Medical College of Nanjing Medical UniversityNanjing, China
| | - Xiaochen Xu
- Key Laboratory for Developmental Genes and Human Disease, Ministry of Education, Institute of Life Sciences, Southeast UniversityNanjing, China
| | - ShaSha Zhang
- Key Laboratory for Developmental Genes and Human Disease, Ministry of Education, Institute of Life Sciences, Southeast UniversityNanjing, China
| | - Junyan Gao
- Health Management and Policy, College of Public Health, Saint Louis University, St. LouisMO, USA
| | - Muhammad Waqas
- Key Laboratory for Developmental Genes and Human Disease, Ministry of Education, Institute of Life Sciences, Southeast UniversityNanjing, China.,Department of Biotechnology, Federal Urdu University of Arts, Science and TechnologyGulshan-e-Iqbal, Pakistan
| | - Chengwen Zhu
- Department of Otolaryngology-Head and Neck Surgery, Nanjing Drum Tower Hospital, Nanjing University Medical SchoolNanjing, China
| | - Yan Chen
- Department of Otorhinolaryngology, Affiliated Eye and ENT Hospital, State Key Laboratory of Medical Neurobiology, Fudan UniversityShanghai, China.,Key Laboratory of Hearing Medicine of National Health and Family Planning CommissionShanghai, China
| | - Xiaoli Zhang
- Department of Otolaryngology-Head and Neck Surgery, Nanjing Drum Tower Hospital, Nanjing University Medical SchoolNanjing, China
| | - Chuanying Xuan
- Key Laboratory for Developmental Genes and Human Disease, Ministry of Education, Institute of Life Sciences, Southeast UniversityNanjing, China
| | - Xia Gao
- Department of Otolaryngology-Head and Neck Surgery, Nanjing Drum Tower Hospital, Nanjing University Medical SchoolNanjing, China
| | - Mingliang Tang
- Key Laboratory for Developmental Genes and Human Disease, Ministry of Education, Institute of Life Sciences, Southeast UniversityNanjing, China
| | - Fangyi Chen
- Department of Biomedical Engineering, Southern University of Science and TechnologyShenzhen, China
| | - Haibo Shi
- Department of Otorhinolaryngology Head and Neck Surgery, The Sixth People's Hospital, Shanghai Jiao Tong UniversityShanghai, China
| | - Huawei Li
- Department of Otorhinolaryngology, Affiliated Eye and ENT Hospital, State Key Laboratory of Medical Neurobiology, Fudan UniversityShanghai, China.,Key Laboratory of Hearing Medicine of National Health and Family Planning CommissionShanghai, China.,Institutes of Biomedical Sciences, Fudan UniversityShanghai, China.,Shanghai Engineering Research Centre of Cochlear ImplantShanghai, China
| | - Renjie Chai
- Key Laboratory for Developmental Genes and Human Disease, Ministry of Education, Institute of Life Sciences, Southeast UniversityNanjing, China.,Research Institute of OtolaryngologyNanjing, China.,Co-innovation Center of Neuroregeneration, Nantong UniversityNantong, China
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Laser-capture micro dissection combined with next-generation sequencing analysis of cell type-specific deafness gene expression in the mouse cochlea. Hear Res 2017; 348:87-97. [PMID: 28263850 DOI: 10.1016/j.heares.2017.02.017] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/11/2015] [Revised: 12/25/2016] [Accepted: 02/28/2017] [Indexed: 12/13/2022]
Abstract
Cochlear implantation (CI), which directly stimulates the cochlear nerves, is the most effective and widely used medical intervention for patients with severe to profound sensorineural hearing loss. The etiology of the hearing loss is speculated to have a major influence of CI outcomes, particularly in cases resulting from mutations in genes preferentially expressed in the spiral ganglion region. To elucidate precise gene expression levels in each part of the cochlea, we performed laser-capture micro dissection in combination with next-generation sequencing analysis and determined the expression levels of all known deafness-associated genes in the organ of Corti, spiral ganglion, lateral wall, and spiral limbs. The results were generally consistent with previous reports based on immunocytochemistry or in situ hybridization. As a notable result, the genes associated with many kinds of syndromic hearing loss (such as Clpp, Hars2, Hsd17b4, Lars2 for Perrault syndrome, Polr1c and Polr1d for Treacher Collins syndrome, Ndp for Norrie Disease, Kal for Kallmann syndrome, Edn3 and Snai2 for Waardenburg Syndrome, Col4a3 for Alport syndrome, Sema3e for CHARGE syndrome, Col9a1 for Sticker syndrome, Cdh23, Cib2, Clrn1, Pcdh15, Ush1c, Ush2a, Whrn for Usher syndrome and Wfs1 for Wolfram syndrome) showed higher levels of expression in the spiral ganglion than in other parts of the cochlea. This dataset will provide a base for more detailed analysis in order to clarify gene functions in the cochlea as well as predict CI outcomes based on gene expression data.
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Xing G, Yao J, Liu C, Wei Q, Qian X, Wu L, Lu Y, Cao X. GPRASP2, a novel causative gene mutated in an X-linked recessive syndromic hearing loss. J Med Genet 2017; 54:426-430. [PMID: 28096187 PMCID: PMC5502311 DOI: 10.1136/jmedgenet-2016-104320] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2016] [Revised: 12/05/2016] [Accepted: 12/22/2016] [Indexed: 11/21/2022]
Abstract
Background A substantial amount of nuclear genes have been identified to be implicated in genetic hearing loss, while X-linked hearing loss is genetically heterogeneous and relatively infrequent. Objective To identify the causative gene mutation in a five-generation Chinese family with an X-linked recessive syndromic hearing loss (SHL). Methods Targeted X-chromosome exome sequencing was conducted, and cosegregation analysis was performed in the members of the affected family. The in silico and expression studies were also performed. Results A 2-bp missense mutation (c.1717_1718GC>AA, p.A573N) in the G protein-coupled receptor associated sorting protein 2 (GPRASP2) gene was identified in four hemizygous male patients and two heterozygous female carriers, which was cosegregated with the clinical phenotypes in this family. In silico analysis supported that this gene mutation is functionally deleterious, and it was detected that homologous Gprasp2 was highly expressed in multiple structures of the mouse cochlea, which suggested that GPRASP2 might be the genetic cause for the described disease phenotypes. Conclusions This study presented a novel X-linked SHL combined with unique and unrecognised clinical features, and a missense variation of GPRASP2 was first identified to be implicated in X-linked SHL.
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Affiliation(s)
- Guangqian Xing
- Department of Otolaryngology, the First Affiliated Hospital of Nanjing Medical University, Nanjing, China
| | - Jun Yao
- Department of Biotechnology, School of Basic Medical Science, Nanjing Medical University, Nanjing, China
| | - Chunyu Liu
- Department of Biotechnology, School of Basic Medical Science, Nanjing Medical University, Nanjing, China
| | - Qinjun Wei
- Department of Biotechnology, School of Basic Medical Science, Nanjing Medical University, Nanjing, China
| | - Xuli Qian
- Department of Biotechnology, School of Basic Medical Science, Nanjing Medical University, Nanjing, China
| | - Lingxin Wu
- Department of Otolaryngology, the First Affiliated Hospital of Nanjing Medical University, Nanjing, China
| | - Yajie Lu
- Department of Biotechnology, School of Basic Medical Science, Nanjing Medical University, Nanjing, China
| | - Xin Cao
- Department of Biotechnology, School of Basic Medical Science, Nanjing Medical University, Nanjing, China
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Pollak A, Lechowicz U, Kędra A, Stawiński P, Rydzanicz M, Furmanek M, Brzozowska M, Mrówka M, Skarżyński H, Skarżyński PH, Ołdak M, Płoski R. Novel and De Novo Mutations Extend Association of POU3F4 with Distinct Clinical and Radiological Phenotype of Hearing Loss. PLoS One 2016; 11:e0166618. [PMID: 27941975 PMCID: PMC5152817 DOI: 10.1371/journal.pone.0166618] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2016] [Accepted: 11/01/2016] [Indexed: 12/18/2022] Open
Abstract
POU3F4 mutations (DFNX2) are the most prevalent among non-syndromic X-linked hearing loss (HL) identified to date. Clinical manifestations of DFNX2 usually comprise congenital HL either sensorineural or mixed, a tendency towards perilymphatic gusher during otologic surgery and temporal bone malformations. The aim of the present study was to screen for POU3F4 mutations in a group of 30 subjects with a suggestive clinical phenotype as well as a group (N = 1671–2018) of unselected hearing loss patients. We also planned to analyze audiological and radiological features in patients with HL caused by POU3F4 defects. The molecular techniques used to detect POU3F4 mutations included whole exome sequencing (WES), Sanger sequencing and real-time polymerase chain reaction. Hearing status was assessed with pure-tone audiometry and auditory brainstem response. Computer tomography scans were evaluated to define the pattern of structural changes in the temporal bones. Six novel (p.Gln27*, p.Glu187*, p.Leu217*, p.Gln275*, p.Gln306*, p.Val324Asp) and two known (p.Ala116fs141*, p.Leu208*) POU3F4 mutations were detected in the studied cohort. All probands with POU3F4 defects suffered from bilateral, prelingual, severe to profound HL. Morphological changes of the temporal bone in these patients presented a similar pattern, including malformations of the internal auditory canal, vestibular aqueduct, modiolus and vestibule. Despite different localization in the POU3F4 gene all mutations severely impair the protein structure affecting at least one functional POU3F4 domain, and results in similar and severe clinical manifestations. Sequencing of the entire POU3F4 gene is recommended in patients with characteristic temporal bone malformations. Results of POU3F4 mutation testing are important not only for a proper genetic counseling, but also for adequate preparation and conduction of a surgical procedure.
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Affiliation(s)
- Agnieszka Pollak
- Department of Genetics, Institute of Physiology and Pathology of Hearing, Warsaw, Poland
| | - Urszula Lechowicz
- Department of Genetics, Institute of Physiology and Pathology of Hearing, Warsaw, Poland
| | - Anna Kędra
- Department of Medical Genetics, Warsaw Medical University, Warsaw, Poland
- Postgraduate School of Molecular Medicine, Warsaw Medical University, Warsaw, Poland
| | - Piotr Stawiński
- Department of Genetics, Institute of Physiology and Pathology of Hearing, Warsaw, Poland
| | | | - Mariusz Furmanek
- Bioimaging Research Center, World Hearing Centre, Institute of Physiology and Pathology of Hearing, Warsaw/Kajetany, Poland
- Department of Radiology and Diagnostic Imaging, Medical Centre for Postgraduate Education, Warsaw, Poland
| | | | - Maciej Mrówka
- Oto-Rhino-Laryngology Surgery Clinic, Institute of Physiology and Pathology of Hearing, Warsaw/Kajetany, Poland
| | - Henryk Skarżyński
- Oto-Rhino-Laryngology Surgery Clinic, Institute of Physiology and Pathology of Hearing, Warsaw/Kajetany, Poland
| | - Piotr H. Skarżyński
- Oto-Rhino-Laryngology Surgery Clinic, Institute of Physiology and Pathology of Hearing, Warsaw/Kajetany, Poland
- Department of Heart Failure and Cardiac Rehabilitation, Medical University of Warsaw, Warsaw, Poland
- Institute of Sensory Organs, Kajetany, Poland
| | - Monika Ołdak
- Department of Genetics, Institute of Physiology and Pathology of Hearing, Warsaw, Poland
- * E-mail: (RP); (MO)
| | - Rafał Płoski
- Department of Medical Genetics, Warsaw Medical University, Warsaw, Poland
- * E-mail: (RP); (MO)
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The nuclear receptor NOR-1 regulates the small muscle protein, X-linked (SMPX) and myotube differentiation. Sci Rep 2016; 6:25944. [PMID: 27181368 PMCID: PMC4867575 DOI: 10.1038/srep25944] [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: 03/09/2016] [Accepted: 04/25/2016] [Indexed: 01/12/2023] Open
Abstract
Recent works have highlighted the role of NOR-1 in both smooth and skeletal muscle, and have proposed this nuclear receptor as a nexus that coordinates muscle performance and metabolic capacity. However, no muscle specific genes regulated by NOR-1 have been identified so far. To identify NOR-1 target genes, we over-expressed NOR-1 in human vascular smooth muscle cells (VSMC). These cells subjected to sustained over-expression of supraphysiological levels of NOR-1 experienced marked phenotypic changes and up-regulated the skeletal muscle protein X-linked (SMPX), a protein typically expressed in striated muscle and associated to cell shape. By transcriptional studies and DNA-protein binding assays, we identified a non-consensus NBRE site in human SMPX promoter, critical for NOR-1 responsiveness. The expression of SMPX was higher in human skeletal muscle myoblasts (HSMM) than in human VSMC, and further increased in HSMM differentiated to myotubes. NOR-1 silencing prevented SMPX expression in HSMM, as well as their differentiation to myotubes, but the up-regulation of SMPX was dispensable for HSMM differentiation. Our results indicate that NOR-1 regulate SMPX in human muscle cells and acts as a muscle regulatory factor, but further studies are required to unravel its role in muscle differentiation and hypertrophy.
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Zazo Seco C, Serrão de Castro L, van Nierop J, Morín M, Jhangiani S, Verver E, Schraders M, Maiwald N, Wesdorp M, Venselaar H, Spruijt L, Oostrik J, Schoots J, van Reeuwijk J, Lelieveld S, Huygen P, Insenser M, Admiraal R, Pennings R, Hoefsloot L, Arias-Vásquez A, de Ligt J, Yntema H, Jansen J, Muzny D, Huls G, van Rossum M, Lupski J, Moreno-Pelayo M, Kunst H, Kremer H, Kremer H. Allelic Mutations of KITLG, Encoding KIT Ligand, Cause Asymmetric and Unilateral Hearing Loss and Waardenburg Syndrome Type 2. Am J Hum Genet 2015; 97:647-60. [PMID: 26522471 DOI: 10.1016/j.ajhg.2015.09.011] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2015] [Accepted: 09/24/2015] [Indexed: 01/04/2023] Open
Abstract
Linkage analysis combined with whole-exome sequencing in a large family with congenital and stable non-syndromic unilateral and asymmetric hearing loss (NS-UHL/AHL) revealed a heterozygous truncating mutation, c.286_303delinsT (p.Ser96Ter), in KITLG. This mutation co-segregated with NS-UHL/AHL as a dominant trait with reduced penetrance. By screening a panel of probands with NS-UHL/AHL, we found an additional mutation, c.200_202del (p.His67_Cys68delinsArg). In vitro studies revealed that the p.His67_Cys68delinsArg transmembrane isoform of KITLG is not detectable at the cell membrane, supporting pathogenicity. KITLG encodes a ligand for the KIT receptor. Also, KITLG-KIT signaling and MITF are suggested to mutually interact in melanocyte development. Because mutations in MITF are causative of Waardenburg syndrome type 2 (WS2), we screened KITLG in suspected WS2-affected probands. A heterozygous missense mutation, c.310C>G (p.Leu104Val), that segregated with WS2 was identified in a small family. In vitro studies revealed that the p.Leu104Val transmembrane isoform of KITLG is located at the cell membrane, as is wild-type KITLG. However, in culture media of transfected cells, the p.Leu104Val soluble isoform of KITLG was reduced, and no soluble p.His67_Cys68delinsArg and p.Ser96Ter KITLG could be detected. These data suggest that mutations in KITLG associated with NS-UHL/AHL have a loss-of-function effect. We speculate that the mechanism of the mutation underlying WS2 and leading to membrane incorporation and reduced secretion of KITLG occurs via a dominant-negative or gain-of-function effect. Our study unveils different phenotypes associated with KITLG, previously associated with pigmentation abnormalities, and will thereby improve the genetic counseling given to individuals with KITLG variants.
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Affiliation(s)
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | - Hannie Kremer
- Hearing & Genes Division, Department of Otorhinolaryngology, Radboud University Medical Center, Nijmegen 6525GA, the Netherlands; The Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Nijmegen 6525GA, the Netherlands; Department of Human Genetics, Radboud University Medical Center, Nijmegen 6525GA, the Netherlands.
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Petersen NK, Jørgensen AW, Ovesen T. Prevalence of various etiologies of hearing loss among cochlear implant recipients: Systematic review and meta-analysis. Int J Audiol 2015; 54:924-32. [PMID: 26642892 PMCID: PMC4732452 DOI: 10.3109/14992027.2015.1091094] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
OBJECTIVE To investigate the etiology of deafness in cochlear implanted children and to address the question whether there is a need for more thorough diagnostics, especially concerning genetics. DESIGN Systematic review. Four databases were searched for studies (year 2000-2014) on cochlear implanted children (n > 100). Studies were excluded if etiology had influenced their inclusion criteria. Eligibility and methodological quality were assessed independently by three authors. The studies' description of diagnostic evaluation was categorized in three groups. STUDY SAMPLE Sixteen studies were included (5069 children). RESULTS The most common etiological categories were 'Unknown' 40.3% (95% CI 32.8 to 48.0), 'Non-syndromic' 22.4% (95% CI 17.1 to 28.2), and 'Postnatal' 11.3% (95% CI 7.2 to 16.2). Studies published after 2006 had a lower proportion of 'Unknown' etiology 35.3% (95% CI 28.0 to 42.8) than older 45.5% (95% CI 31.0 to 60.4). Important information was missing from several studies: 11 (69%) studies did not provide detailed description on diagnostic evaluation of the etiology of deafness and had a higher proportion of 'Unknown' etiology. CONCLUSIONS In order to ensure a higher level of comparability in future studies, we recommend agreement upon an international standard of diagnostics and the introduction of an international standard for reporting etiology.
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Affiliation(s)
| | - Anders W Jørgensen
- a Department of Otorhinolaryngology , Aarhus University Hospital , Aarhus C , Denmark
| | - Therese Ovesen
- a Department of Otorhinolaryngology , Aarhus University Hospital , Aarhus C , Denmark
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De novo large genomic deletions involving POU3F4 in incomplete partition type III inner ear anomaly in East Asian populations and implications for genetic counseling. Otol Neurotol 2015; 36:184-90. [PMID: 24608376 DOI: 10.1097/mao.0000000000000343] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVE The aim of this study was to understand the prevalence and molecular genetic etiology of incomplete partition type III (IP type III) anomaly in Koreans. We also attempted to verify the prevalence of genomic deletions in the DFNX2 locus and to look for association between inheritance patterns and mutation type in East Asian IP type III subjects. STUDY DESIGN Retrospective case review. SETTING Tertiary referral center. PATIENTS Subjects with IP type III anomaly and their biological mothers. INTERVENTIONS Sanger sequencing, array-comparative genomic hybridization (aCGH), and PCR were performed. We also analyzed the type and inheritance of the causative genetic abnormality in East Asian DFNX2 patients. MAIN OUTCOME MEASURE Mutation type and occurrence. RESULTS We identified IP type III in 10 (4.8%) of 206 patients with an inner ear abnormality. We confirmed an etiologic homogeneity, DFNX2, of the IP type III in this Korean population. Two (20%) of the 10 DFNX2 carried a large genomic deletion affecting POU3F4, as proved by aCGH. PCR confirmed that the 2 deletions occurred de novo. Genetic alteration occurred de novo in 29.4% (5/17) of all reported Korean IP type III cases. From this study and literature review, we observed a striking difference of de novo occurrence rate (75% versus 12.5%, p = 0.032) between large genomic deletions and point mutations in East Asian population. CONCLUSIONS Our data suggest that different POU3F4 mutations might show different recurrence rate in siblings of the IP type III families, especially in East Asian population. Genetic counseling should be provided accordingly.
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Hu H, Wienker TF, Musante L, Kalscheuer VM, Kahrizi K, Najmabadi H, Ropers HH. Integrated sequence analysis pipeline provides one-stop solution for identifying disease-causing mutations. Hum Mutat 2015; 35:1427-35. [PMID: 25219469 DOI: 10.1002/humu.22695] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2014] [Accepted: 08/28/2014] [Indexed: 12/23/2022]
Abstract
Next-generation sequencing has greatly accelerated the search for disease-causing defects, but even for experts the data analysis can be a major challenge. To facilitate the data processing in a clinical setting, we have developed a novel medical resequencing analysis pipeline (MERAP). MERAP assesses the quality of sequencing, and has optimized capacity for calling variants, including single-nucleotide variants, insertions and deletions, copy-number variation, and other structural variants. MERAP identifies polymorphic and known causal variants by filtering against public domain databases, and flags nonsynonymous and splice-site changes. MERAP uses a logistic model to estimate the causal likelihood of a given missense variant. MERAP considers the relevant information such as phenotype and interaction with known disease-causing genes. MERAP compares favorably with GATK, one of the widely used tools, because of its higher sensitivity for detecting indels, its easy installation, and its economical use of computational resources. Upon testing more than 1,200 individuals with mutations in known and novel disease genes, MERAP proved highly reliable, as illustrated here for five families with disease-causing variants. We believe that the clinical implementation of MERAP will expedite the diagnostic process of many disease-causing defects.
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Affiliation(s)
- Hao Hu
- Max-Planck Institute for Molecular Genetics, Berlin, Germany
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Gao X, Su Y, Chen YL, Han MY, Yuan YY, Xu JC, Xin F, Zhang MG, Huang SS, Wang GJ, Kang DY, Guan LP, Zhang JG, Dai P. Identification of Two Novel Compound Heterozygous PTPRQ Mutations Associated with Autosomal Recessive Hearing Loss in a Chinese Family. PLoS One 2015; 10:e0124757. [PMID: 25919374 PMCID: PMC4412678 DOI: 10.1371/journal.pone.0124757] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2014] [Accepted: 03/05/2015] [Indexed: 11/25/2022] Open
Abstract
Mutations in PTPRQ are associated with deafness in humans due to defects of stereocilia in hair cells. Using whole exome sequencing, we identified responsible gene of family 1572 with autosomal recessively non-syndromic hearing loss (ARNSHL). We also used DNA from 74 familial patients with ARNSHL and 656 ethnically matched control chromosomes to perform extended variant analysis. We identified two novel compound heterozygous missense mutations, c. 3125 A>G p.D1042G (maternal allele) and c.5981 A>G p.E1994G (paternal allele), in the PTPRQ gene, as the cause of recessively inherited sensorineural hearing loss in family 1572. Both variants co-segregated with hearing loss phenotype in family 1572, but were absent in 74 familial patients. Heterozygosity for c. 3125 A>G was identified in two samples from unaffected Chinese individuals (656 chromosomes). Therefore, the hearing loss in this family was caused by two novel compound heterozygous mutations in PTPRQ.
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Affiliation(s)
- Xue Gao
- Department of Otorhinolaryngology, Head and Neck Surgery, PLA General Hospital, Beijing, P. R. China
- Department of Otolaryngology, Hainan Branch of PLA General Hospital, Sanya, P. R. China
- Department of Otorhinolaryngology, the Second Artillery General Hospital, Beijing, P. R. China
| | - Yu Su
- Department of Otorhinolaryngology, Head and Neck Surgery, PLA General Hospital, Beijing, P. R. China
- Department of Otolaryngology, Hainan Branch of PLA General Hospital, Sanya, P. R. China
| | | | - Ming-Yu Han
- Department of Otorhinolaryngology, Head and Neck Surgery, PLA General Hospital, Beijing, P. R. China
| | - Yong-Yi Yuan
- Department of Otorhinolaryngology, Head and Neck Surgery, PLA General Hospital, Beijing, P. R. China
- Department of Otolaryngology, Hainan Branch of PLA General Hospital, Sanya, P. R. China
| | - Jin-Cao Xu
- Department of Otorhinolaryngology, the Second Artillery General Hospital, Beijing, P. R. China
| | - Feng Xin
- Department of Otorhinolaryngology, Head and Neck Surgery, PLA General Hospital, Beijing, P. R. China
| | - Mei-Guang Zhang
- Department of Otorhinolaryngology, the Second Artillery General Hospital, Beijing, P. R. China
| | - Sha-Sha Huang
- Department of Otorhinolaryngology, Head and Neck Surgery, PLA General Hospital, Beijing, P. R. China
| | - Guo-Jian Wang
- Department of Otorhinolaryngology, Head and Neck Surgery, PLA General Hospital, Beijing, P. R. China
| | - Dong-Yang Kang
- Department of Otorhinolaryngology, Head and Neck Surgery, PLA General Hospital, Beijing, P. R. China
| | | | | | - Pu Dai
- Department of Otorhinolaryngology, Head and Neck Surgery, PLA General Hospital, Beijing, P. R. China
- Department of Otolaryngology, Hainan Branch of PLA General Hospital, Sanya, P. R. China
- * E-mail:
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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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Abstract
Next-generation sequencing (NGS) technologies have played a central role in the genetic revolution. These technologies, especially whole-exome sequencing, have become the primary tool of geneticists to identify the causative DNA variants in Mendelian disorders, including hereditary deafness. Current research estimates that 1% of all human genes have a function in hearing. To date, mutations in over 80 genes have been reported to cause nonsyndromic hearing loss (NSHL). Strikingly, more than a quarter of all known genes related to NSHL were discovered in the past 5 years via NGS technologies. In this article, we review recent developments in the usage of NGS for hereditary deafness, with an emphasis on whole-exome sequencing.
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Nishio SY, Usami SI. Deafness gene variations in a 1120 nonsyndromic hearing loss cohort: molecular epidemiology and deafness mutation spectrum of patients in Japan. Ann Otol Rhinol Laryngol 2015; 124 Suppl 1:49S-60S. [PMID: 25788563 DOI: 10.1177/0003489415575059] [Citation(s) in RCA: 61] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
OBJECTIVES To elucidate the molecular epidemiology of hearing loss in a large number of Japanese patients analyzed using massively parallel DNA sequencing (MPS) of target genes. METHODS We performed MPS of target genes using the Ion PGM system with the Ion AmpliSeq and HiSeq 2000 systems using SureSelect in 1389 samples (1120 nonsyndromic hearing loss cases and 269 normal hearing controls). We filtered the variants identified using allele frequencies in a large number of controls and 12 predication program scores. RESULTS We identified 8376 kinds of variants in the 1389 samples, and 409 835 total variants were detected. After filtering the variants, we selected 2631 kinds of candidate variants. The number of GJB2 mutations was exceptionally high among these variants, followed by those in CDH23, SLC26A4, MYO15A, COL11A2, MYO7A, and OTOF. CONCLUSIONS We performed a large number of MPS analyses and clarified the genetic background of Japanese patients with hearing loss. This data set will be a powerful tool to discover rare causative gene mutations in highly heterogeneous monogenic diseases and reveal the genetic epidemiology of deafness.
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Affiliation(s)
- Shin-Ya Nishio
- Department of Otorhinolaryngology, Shinshu University School of Medicine, Matsumoto, Japan Department of Hearing Implant Sciences, Shinshu University School of Medicine, Matsumoto, Japan
| | - Shin-Ichi Usami
- Department of Otorhinolaryngology, Shinshu University School of Medicine, Matsumoto, Japan Department of Hearing Implant Sciences, Shinshu University School of Medicine, Matsumoto, Japan
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Bademci G, Lasisi A, Yariz KO, Montenegro P, Menendez I, Vinueza R, Paredes R, Moreta G, Subasioglu A, Blanton S, Fitoz S, Incesulu A, Sennaroglu L, Tekin M. Novel domain-specific POU3F4 mutations are associated with X-linked deafness: examples from different populations. BMC MEDICAL GENETICS 2015; 16:9. [PMID: 25928534 PMCID: PMC4422282 DOI: 10.1186/s12881-015-0149-2] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/12/2014] [Accepted: 01/29/2015] [Indexed: 01/17/2023]
Abstract
Background Mutations in the POU3F4 gene cause X-linked deafness type 3 (DFN3), which is characterized by inner ear anomalies. Methods Three Turkish, one Ecuadorian, and one Nigerian families were included based on either inner ear anomalies detected in probands or X-linked family histories. Exome sequencing and/or Sanger sequencing were performed in order to identify the causative DNA variants in these families. Results Four novel, c.707A>C (p.(Glu236Ala)), c.772delG (p.(Glu258ArgfsX30)), c.902C>T (p.(Pro301Leu)), c.987T>C (p.(Ile308Thr)), and one previously reported mutation c.346delG (p.(Ala116ProfsX26)) in POU3F4, were identified. All mutations identified are predicted to affect the POU-specific or POU homeo domains of the protein and co-segregated with deafness in all families. Conclusions Expanding the spectrum of POU3F4 mutations in different populations along with their associated phenotypes provides better understanding of their clinical importance and will be helpful in clinical evaluation and counseling of the affected individuals. Electronic supplementary material The online version of this article (doi:10.1186/s12881-015-0149-2) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Guney Bademci
- John P. Hussmann Institute for Human Genomics and John T. Macdonald Foundation, Department of Human Genetics, Miller school of Medicine, University of Miami, 1501 NW 10th Avenue, BRB-610 (M-860), Miami, FL, 33136, USA.
| | - Akeem Lasisi
- John P. Hussmann Institute for Human Genomics and John T. Macdonald Foundation, Department of Human Genetics, Miller school of Medicine, University of Miami, 1501 NW 10th Avenue, BRB-610 (M-860), Miami, FL, 33136, USA. .,Department of Otorhinolaryngology, College of Medicine, University of Ibadan, Ibadan, Nigeria.
| | - Kemal O Yariz
- John P. Hussmann Institute for Human Genomics and John T. Macdonald Foundation, Department of Human Genetics, Miller school of Medicine, University of Miami, 1501 NW 10th Avenue, BRB-610 (M-860), Miami, FL, 33136, USA.
| | - Paola Montenegro
- Departamento de Genetica, Hospital de Especialidades FFAA, Quito, Ecuador.
| | - Ibis Menendez
- John P. Hussmann Institute for Human Genomics and John T. Macdonald Foundation, Department of Human Genetics, Miller school of Medicine, University of Miami, 1501 NW 10th Avenue, BRB-610 (M-860), Miami, FL, 33136, USA.
| | - Rodrigo Vinueza
- Departamento de Genetica, Hospital de Especialidades FFAA, Quito, Ecuador.
| | - Rosario Paredes
- Departamento de Genetica, Hospital de Especialidades FFAA, Quito, Ecuador.
| | - Germania Moreta
- Departamento de Genetica, Hospital de Especialidades FFAA, Quito, Ecuador.
| | - Asli Subasioglu
- John P. Hussmann Institute for Human Genomics and John T. Macdonald Foundation, Department of Human Genetics, Miller school of Medicine, University of Miami, 1501 NW 10th Avenue, BRB-610 (M-860), Miami, FL, 33136, USA. .,Department of Medical Genetics, Izmir Katip Celebi University, Ataturk Training and Research Hospital, Izmir, Turkey.
| | - Susan Blanton
- John P. Hussmann Institute for Human Genomics and John T. Macdonald Foundation, Department of Human Genetics, Miller school of Medicine, University of Miami, 1501 NW 10th Avenue, BRB-610 (M-860), Miami, FL, 33136, USA.
| | - Suat Fitoz
- Department of Radiodiagnostics, Ankara University School of Medicine, Ankara, Turkey.
| | - Armagan Incesulu
- Department of Otorhinolaryngology, Eskisehir Osmangazi University School of Medicine, Eskisehir, Turkey.
| | - Levent Sennaroglu
- Department of Otorhinolaryngology, Hacettepe University School of Medicine, Ankara, Turkey.
| | - Mustafa Tekin
- John P. Hussmann Institute for Human Genomics and John T. Macdonald Foundation, Department of Human Genetics, Miller school of Medicine, University of Miami, 1501 NW 10th Avenue, BRB-610 (M-860), Miami, FL, 33136, USA.
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Downsloping high-frequency hearing loss due to inner ear tricellular tight junction disruption by a novel ILDR1 mutation in the Ig-like domain. PLoS One 2015; 10:e0116931. [PMID: 25668204 PMCID: PMC4323246 DOI: 10.1371/journal.pone.0116931] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2014] [Accepted: 12/16/2014] [Indexed: 11/19/2022] Open
Abstract
The immunoglobulin (Ig)-like domain containing receptor 1 (ILDR1) gene encodes angulin-2/ILDR1, a recently discovered tight junction protein, which forms tricellular tight junction (tTJ) structures with tricellulin and lipolysis-stimulated lipoprotein receptor (LSR) at tricellular contacts (TCs) in the inner ear. Previously reported recessive mutations within ILDR1 have been shown to cause severe to profound nonsyndromic sensorineural hearing loss (SNHL), DFNB42. Whole-exome sequencing of a Korean multiplex family segregating partial deafness identified a novel homozygous ILDR1 variant (p.P69H) within the Ig-like domain. To address the pathogenicity of p.P69H, the angulin-2/ILDR1 p.P69H variant protein, along with the previously reported pathogenic ILDR1 mutations, was expressed in angulin-1/LSR knockdown epithelial cells. Interestingly, partial mislocalization of the p.P69H variant protein and tricellulin at TCs was observed, in contrast to a severe mislocalization and complete failure of tricellulin recruitment of the other reported ILDR1 mutations. Additionally, three-dimensional protein modeling revealed that angulin-2/ILDR1 contributed to tTJ by forming a homo-trimer structure through its Ig-like domain, and the p.P69H variant was predicted to disturb homo-trimer formation. In this study, we propose a possible role of angulin-2/ILDR1 in tTJ formation in the inner ear and a wider audiologic phenotypic spectrum of DFNB42 caused by mutations within ILDR1.
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Lin F, Li D, Wang P, Fan D, De J, Zhu W. Autosomal recessive non-syndromic hearing loss is caused by novel compound heterozygous mutations in TMC1 from a Tibetan Chinese family. Int J Pediatr Otorhinolaryngol 2014; 78:2216-21. [PMID: 25458163 DOI: 10.1016/j.ijporl.2014.10.016] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/24/2014] [Revised: 10/07/2014] [Accepted: 10/10/2014] [Indexed: 10/24/2022]
Abstract
OBJECTIVES Hearing loss is the most common sensory disorder worldwide. Biallelic mutations in 42 different genes have been identified as associated with autosomal recessive non-syndromic hearing loss (ARNSHL). One of the common genes responsible for ARNSHL is TMC1. TMC1 mutations have been reported to cause non-syndromic hearing loss in a variety of populations. The current study is designed to investigate mutations prevalent among Chinese ethnic groups with ARNSHL. METHODS Targeted exome sequencing (TES) was employed to study the genetic causes of two siblings with ARNSHL in a Tibetan Chinese family. Variants identified by TES were further confirmed by Sanger sequencing. RESULTS We identified two distinct variants in the TMC1 gene in two deaf siblings of one Tibetan Chinese family using TES. Both siblings inherited a paternal allele containing a deletion of c.1396_1398AAC (p.Asn466del) and a maternal allele containing an insertion of c.2210_2211insCT (p.Glu737HisfsX2). The former disrupts a highly conserved residue in the large intracellular loop domain adjacent to the fourth transmembrane domain, and the latter causes a truncation of a portion of the C-terminal domain. These variants were compound heterzygous and segregated with the hearing impairment in this family. CONCLUSION The novel compound heterozygous mutant alleles of TMC1 identified in this study were responsible for the ARNSHL in this Tibetan Chinese family. Although compound heterozygous mutations in TMC1 occurring in different TMC1 domains have been previously described in Han Chinese; this result suggests that the TMC1 variants contributing to hereditary deafness in Chinese populations may be more complex than initially assumed and that sequence-based diagnostics will be required for a comprehensive evaluation of ARNSHL.
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Affiliation(s)
- Fangzhu Lin
- Department of Otolaryngology-Head and Neck Surgery, First Hospital of Jilin University, Changchun 130021, China
| | - Dejun Li
- Center for Prenatal Diagnosis, First Hospital of Jilin University, Changchun 130021, China
| | - Ping Wang
- Department of Otolaryngology-Head and Neck Surgery, First Hospital of Jilin University, Changchun 130021, China
| | - Dongyan Fan
- School of Medicine, Tibet University, Lhasa 850000, China
| | - Ji De
- School of Medicine, Tibet University, Lhasa 850000, China
| | - Wei Zhu
- Department of Otolaryngology-Head and Neck Surgery, First Hospital of Jilin University, Changchun 130021, China.
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Park JH, Kim NKD, Kim AR, Rhee J, Oh SH, Koo JW, Nam JY, Park WY, Choi BY. Exploration of molecular genetic etiology for Korean cochlear implantees with severe to profound hearing loss and its implication. Orphanet J Rare Dis 2014; 9:167. [PMID: 25373420 PMCID: PMC4243193 DOI: 10.1186/s13023-014-0167-8] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2014] [Accepted: 10/17/2014] [Indexed: 02/01/2023] Open
Abstract
Background Severe to profound sensorineural hearing loss (SNHL) requires cochlear implantation (CI) for auditory rehabilitation. Etiologic diagnoses can contribute to candidacy selection and decision-making regarding the timing of successful CI. However, few studies have been performed to address the etiologic spectrum of severe SNHL in the population where there is no consanguineous marriage and the majority of SNHL cases are sporadic in small sized families. The authors sought to comprehensively understand the etiologies of Korean cochlear implantees by incorporating the targeted resequencing of 204 candidate deafness genes (TRS-204) and a phenotype-driven candidate gene approach. Methods Ninety-three that consented to molecular genetic testing and underwent at least one molecular genetic test were included. Patients with a characteristic Phenotypic marker were subject to Sanger sequencing to detect variants in corresponding candidate genes. The rest of patients without any prominent phenotype were tested on GJB2. Next, TRS-204 was applied in GJB2-negative cases without any phenotypic marker. In addition, the sibling recurrence-risk of SNHL among families with non-diagnostic genotypes after TRS-204 was performed to gain insight of etiologies in non-diagnostic cases. Results Overall, we could find causative variants in 51 (54.8%) of the 93 cochlear implantees. Thirty (32.3%) probands could be diagnosed by direct Sanger sequencing of candidate genes selected by their phenotypes. GJB2 sequencing added 10 subjects to the group with a diagnostic genotype. TRS-204 could detect a causative variant from additional 11 cases (11.8%). We could not detect any pathogenic deletion or duplication on 204 target genes. The sibling recurrence-risk of SNHL among 42 genetically undiagnosed families with 0.03 (1/38) was significantly lower than among genetically diagnosed recessive families with 0.19 (7/37). Conclusion Despite that the majority of severe or more degree of SNHL occurs sporadically in Koreans, at least 54.8% of such cases that were willing to join the genetic study in the Korean population are monogenic Mendelian disorders with convincing causative variants. This study also indicates that a substantial portion of unsolved cases after applying our current protocol are predicted to have non-genetic or complex etiology rather than a Mendelian genetic disorder involving new genes beyond the 204 target genes. Electronic supplementary material The online version of this article (doi:10.1186/s13023-014-0167-8) contains supplementary material, which is available to authorized users.
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The expanding spectrum of PRPS1-associated phenotypes: three novel mutations segregating with X-linked hearing loss and mild peripheral neuropathy. Eur J Hum Genet 2014; 23:766-73. [PMID: 25182139 DOI: 10.1038/ejhg.2014.168] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2014] [Revised: 05/30/2014] [Accepted: 06/05/2014] [Indexed: 11/09/2022] Open
Abstract
Next-generation sequencing is currently the technology of choice for gene/mutation discovery in genetically-heterogeneous disorders, such as inherited sensorineural hearing loss (HL). Whole-exome sequencing of a single Italian proband affected by non-syndromic HL identified a novel missense variant within the PRPS1 gene (NM_002764.3:c.337G>T (p.A113S)) segregating with post-lingual, bilateral, progressive deafness in the proband's family. Defects in this gene, encoding the phosphoribosyl pyrophosphate synthetase 1 (PRS-I) enzyme, determine either X-linked syndromic conditions associated with hearing impairment (eg, Arts syndrome and Charcot-Marie-Tooth neuropathy type X-5) or non-syndromic HL (DFNX1). A subsequent screening of the entire PRPS1 gene in 16 unrelated probands from X-linked deaf families led to the discovery of two additional missense variants (c.343A>G (p.M115V) and c.925G>T (p.V309F)) segregating with hearing impairment, and associated with mildly-symptomatic peripheral neuropathy. All three variants result in a marked reduction (>60%) of the PRS-I activity in the patients' erythrocytes, with c.343A>G (p.M115V) and c.925G>T (p.V309F) affecting more severely the enzyme function. Our data significantly expand the current spectrum of pathogenic variants in PRPS1, confirming that they are associated with a continuum disease spectrum, thus stressing the importance of functional studies and detailed clinical investigations for genotype-phenotype correlation.
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Eftestøl E, Alver TN, Gundersen K, Bruusgaard JC. Overexpression of SMPX in adult skeletal muscle does not change skeletal muscle fiber type or size. PLoS One 2014; 9:e99232. [PMID: 24936977 PMCID: PMC4060999 DOI: 10.1371/journal.pone.0099232] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2014] [Accepted: 05/12/2014] [Indexed: 01/12/2023] Open
Abstract
Mechanical factors such as stretch are thought to be important in the regulation of muscle phenotype. Small muscle protein X-linked (SMPX) is upregulated by stretch in skeletal muscle and has been suggested to serve both as a transcription factor and a mechanosensor, possibly giving rise to changes in both fiber size and fiber type. We have used in vivo confocal imaging to study the subcellular localization of SMPX in skeletal muscle fibers of adult rats using a SMPX-EGFP fusion protein. The fusion protein was localized predominantly in repetitive double stripes flanking the Z-disc, and was excluded from all nuclei. This localization would be consistent with SMPX being a mechanoreceptor, but not with SMPX playing a role as a transcription factor. In vivo overexpression of ectopic SMPX in skeletal muscle of adult mice gave no significant changes in fiber type distribution or cross sectional area, thus a role of SMPX in regulating muscle phenotype remains unclear.
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Affiliation(s)
- Einar Eftestøl
- Department of Biosciences, University of Oslo, Oslo, Norway
| | | | | | - Jo C. Bruusgaard
- Department of Biosciences, University of Oslo, Oslo, Norway
- Atlantis Medical University College, Oslo, Norway
- * E-mail:
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50
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Stanton SG, Griffin A, Stockley TL, Brown C, Young TL, Benteau T, Abdelfatah N. X-linked hearing loss: two gene mutation examples provide generalizable implications for clinical care. Am J Audiol 2014; 23:190-200. [PMID: 24687041 DOI: 10.1044/2014_aja-13-0040] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
PURPOSE To describe the inheritance patterns and auditory phenotype features of 3 Canadian families with mutations in 2 X-linked "deafness" genes (DFNX). METHOD Audiological, medical, and family histories were collected and family members interviewed to compare hearing thresholds and case histories between cases with mutations in SMPX versus POU3F4. RESULTS The family pedigrees reveal characteristic X-linked inheritance patterns. Phenotypic features associated with the SMPX (DFNX4) mutation include early onset in males with rapid progression from mild and flat to sloping sensorineural loss, with highly variable onset and hearing loss severity in females. In contrast, phenotypic features associated with the POU3F4 (DFNX2) mutation are characterized by an early onset, mixed hearing loss with fluctuation in males, and a normal hearing phenotype reported for females. CONCLUSIONS The study shows how this unique inheritance pattern and both gender and mutation-specific phenotype variations can alert audiologists to the presence of X-linked genetic etiologies in their clinical practice. By incorporating this knowledge into clinical decision making, audiologists can facilitate the early identification of X-linked hearing loss and contribute to the effective team management of affected families.
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Affiliation(s)
| | | | - Tracy L. Stockley
- Hospital for Sick Children, Toronto, Ontario, Canada, and University of Toronto, Ontario, Canada
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