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Hodge S, Lopez IA, Cronkite A, House J, Matsui H, Ishiyama G, Ishiyama A. Dynamic Molecular Markers of Otosclerosis in the Human Cochlea. Ann Otol Rhinol Laryngol 2024; 133:390-399. [PMID: 38197255 PMCID: PMC11057044 DOI: 10.1177/00034894231225134] [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] [Indexed: 01/11/2024]
Abstract
OBJECTIVE To investigate the role and distribution of various molecular markers using immunohistochemistry and immunofluorescence to further elucidate and understand the pathogenesis of otosclerosis. METHODS Archival celloidin formalin-fixed 20-micron thick histologic sections from 7 patients diagnosed with otosclerosis were studied and compared to controls. Sections in the mid-modiolar region were immunoreacted with rabbit polyclonal antibodies against nidogen-1, β2-laminin, collagen-IX, BSP, and monoclonal antibodies against TGF β-1 and ubiquitin. Digital images were acquired using a high-resolution light and laser confocal microscope. RESULTS Nidogen-1, BSP, and collagen-IX were expressed in the otospongiotic regions, and to lesser extent, in the otosclerotic regions, the latter previously believed to be inactive. β2-laminin and ubiquitin were uniformly expressed in both otospongiotic and otosclerotic regions. There was a basal level of expression of all of these markers in the normal hearing and sensorineural hearing loss specimens utilized as control. TGF β -1, however, though present in the otosclerosis bones, was absent in the normal hearing and sensorineural hearing loss controls. CONCLUSIONS Our results propose that the activity and function of TGF-1 may play a key role in the development and pathogenesis of otosclerosis. Further studies utilizing a higher number of temporal bone specimens will be helpful for future analysis and to help decipher its role as a potential target in therapeutic interventions.
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Affiliation(s)
- Sarah Hodge
- Department of Otolaryngology—Head and Neck Surgery, Augusta University/Medical College of Georgia, Augusta, GA, USA
| | - Ivan A Lopez
- Department of Otolaryngology—Head and Neck Surgery, University of California Los Angeles, Los Angeles, CA, USA
| | - Alex Cronkite
- Department of Otolaryngology—Head and Neck Surgery, University of California Los Angeles, Los Angeles, CA, USA
| | | | | | - Gail Ishiyama
- Department of Neurology, David Geffen School of Medicine at UCLA, Los Angeles, CA, USA
| | - Akira Ishiyama
- Department of Otolaryngology—Head and Neck Surgery, University of California Los Angeles, Los Angeles, CA, USA
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2
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Drabkin M, Jean MM, Noy Y, Halperin D, Yogev Y, Wormser O, Proskorovski-Ohayon R, Dolgin V, Levaot N, Brumfeld V, Ovadia S, Kishner M, Kazenell U, Avraham KB, Shelef I, Birk OS. SMARCA4 mutation causes human otosclerosis and a similar phenotype in mice. J Med Genet 2024; 61:117-124. [PMID: 37399313 PMCID: PMC10756932 DOI: 10.1136/jmg-2023-109264] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2023] [Accepted: 06/09/2023] [Indexed: 07/05/2023]
Abstract
BACKGROUND Otosclerosis is a common cause of adult-onset progressive hearing loss, affecting 0.3%-0.4% of the population. It results from dysregulation of bone homeostasis in the otic capsule, most commonly leading to fixation of the stapes bone, impairing sound conduction through the middle ear. Otosclerosis has a well-known genetic predisposition including familial cases with apparent autosomal dominant mode of inheritance. While linkage analysis and genome-wide association studies suggested an association with several genomic loci and with genes encoding structural proteins involved in bone formation or metabolism, the molecular genetic pathophysiology of human otosclerosis is yet mostly unknown. METHODS Whole-exome sequencing, linkage analysis, generation of CRISPR mutant mice, hearing tests and micro-CT. RESULTS Through genetic studies of kindred with seven individuals affected by apparent autosomal dominant otosclerosis, we identified a disease-causing variant in SMARCA4, encoding a key component of the PBAF chromatin remodelling complex. We generated CRISPR-Cas9 transgenic mice carrying the human mutation in the mouse SMARCA4 orthologue. Mutant Smarca4+/E1548K mice exhibited marked hearing impairment demonstrated through acoustic startle response and auditory brainstem response tests. Isolated ossicles of the auditory bullae of mutant mice exhibited a highly irregular structure of the incus bone, and their in situ micro-CT studies demonstrated the anomalous structure of the incus bone, causing disruption in the ossicular chain. CONCLUSION We demonstrate that otosclerosis can be caused by a variant in SMARCA4, with a similar phenotype of hearing impairment and abnormal bone formation in the auditory bullae in transgenic mice carrying the human mutation in the mouse SMARCA4 orthologue.
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Affiliation(s)
- Max Drabkin
- The Morris Kahn Laboratory of Human Genetics, Shraga Segal Department of Microbiology, Immunology and Genetics, Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer Sheva, Israel
| | - Matan M Jean
- The Morris Kahn Laboratory of Human Genetics, Shraga Segal Department of Microbiology, Immunology and Genetics, Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer Sheva, Israel
| | - Yael Noy
- Department of Human Molecular Genetics and Biochemistry, Faculty of Medicine and Sagol School of Neuroscience, Tel Aviv University, Tel Aviv, Israel
| | - Daniel Halperin
- The Morris Kahn Laboratory of Human Genetics, Shraga Segal Department of Microbiology, Immunology and Genetics, Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer Sheva, Israel
| | - Yuval Yogev
- The Morris Kahn Laboratory of Human Genetics, Shraga Segal Department of Microbiology, Immunology and Genetics, Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer Sheva, Israel
| | - Ohad Wormser
- The Morris Kahn Laboratory of Human Genetics, Shraga Segal Department of Microbiology, Immunology and Genetics, Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer Sheva, Israel
| | - Regina Proskorovski-Ohayon
- The Morris Kahn Laboratory of Human Genetics, Shraga Segal Department of Microbiology, Immunology and Genetics, Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer Sheva, Israel
| | - Vadim Dolgin
- The Morris Kahn Laboratory of Human Genetics, Shraga Segal Department of Microbiology, Immunology and Genetics, Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer Sheva, Israel
| | - Noam Levaot
- Department of Physiology and Cell Biology, Ben-Gurion University of the Negev, Beer-Sheva, Israel
| | - Vlad Brumfeld
- Department of Chemical Research Support, Weizmann Institute of Science, Rehovot, Israel
| | - Shira Ovadia
- Ben-Gurion University of the Negev, Beer-Sheva, Israel
| | - Mor Kishner
- Department of Life Sciences, Ben-Gurion University of the Negev, Beer-Sheva, Israel
| | - Udi Kazenell
- Department of Otolaryngology, Head and Neck Surgery, Kaplan Medical Center, Rehovot, Israel
| | - Karen B Avraham
- Department of Human Molecular Genetics and Biochemistry, Faculty of Medicine and Sagol School of Neuroscience, Tel Aviv University, Tel Aviv, Israel
| | - Ilan Shelef
- Department of Radiology, Ben-Gurion University of the Negev, Beer-Sheva, Israel
| | - Ohad S Birk
- The Morris Kahn Laboratory of Human Genetics, Shraga Segal Department of Microbiology, Immunology and Genetics, Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer Sheva, Israel
- Genetics Institute, Soroka University Medical Center, Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer-Sheva, Israel
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3
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Targeted Resequencing of Otosclerosis Patients from Different Populations Replicates Results from a Previous Genome-Wide Association Study. J Clin Med 2022; 11:jcm11236978. [PMID: 36498562 PMCID: PMC9737413 DOI: 10.3390/jcm11236978] [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: 10/28/2022] [Revised: 11/17/2022] [Accepted: 11/22/2022] [Indexed: 11/29/2022] Open
Abstract
Otosclerosis is one of the most common causes of hearing loss in young adults. It has a prevalence of 0.3-0.4% in the European population. Clinical symptoms usually occur between the second and fifth decade of life. Different studies have been performed to unravel the genetic architecture of the disease. Recently, a genome-wide association study (GWAS) identified 15 novel risk loci and replicated the regions of three previously reported candidate genes. In this study, seven candidate genes from the GWAS were resequenced using single molecule molecular inversion probes (smMIPs). smMIPs were used to capture the exonic regions and the 3' and 5' untranslated regions (UTR). Discovered variants were tested for association with the disease using single variant and gene-based association analysis. The single variant results showed that 13 significant variants were associated with otosclerosis. Associated variants were found in five of the seven genes studied here, including AHSG, LINC01482, MARK3, SUPT3H and RELN. Conversely, burden testing did not show a major role of rare variants in the disease. In conclusion, this study was able to replicate five out of seven candidate genes reported in the previous GWAS. This association is likely mainly driven by common variants.
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4
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A pathogenic deletion in Forkhead Box L1 (FOXL1) identifies the first otosclerosis (OTSC) gene. Hum Genet 2021; 141:965-979. [PMID: 34633540 PMCID: PMC9034980 DOI: 10.1007/s00439-021-02381-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2021] [Accepted: 09/30/2021] [Indexed: 12/23/2022]
Abstract
Otosclerosis is a bone disorder of the otic capsule and common form of late-onset hearing impairment. Considered a complex disease, little is known about its pathogenesis. Over the past 20 years, ten autosomal dominant loci (OTSC1-10) have been mapped but no genes identified. Herein, we map a new OTSC locus to a 9.96 Mb region within the FOX gene cluster on 16q24.1 and identify a 15 bp coding deletion in Forkhead Box L1 co-segregating with otosclerosis in a Caucasian family. Pre-operative phenotype ranges from moderate to severe hearing loss to profound sensorineural loss requiring a cochlear implant. Mutant FOXL1 is both transcribed and translated and correctly locates to the cell nucleus. However, the deletion of 5 residues in the C-terminus of mutant FOXL1 causes a complete loss of transcriptional activity due to loss of secondary (alpha helix) structure. FOXL1 (rs764026385) was identified in a second unrelated case on a shared background. We conclude that FOXL1 (rs764026385) is pathogenic and causes autosomal dominant otosclerosis and propose a key inhibitory role for wildtype Foxl1 in bone remodelling in the otic capsule. New insights into the molecular pathology of otosclerosis from this study provide molecular targets for non-invasive therapeutic interventions.
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5
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Genetics of otosclerosis: finally catching up with other complex traits? Hum Genet 2021; 141:939-950. [PMID: 34498117 DOI: 10.1007/s00439-021-02357-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2021] [Accepted: 08/29/2021] [Indexed: 10/20/2022]
Abstract
Otosclerosis is a relatively common cause of hearing impairment, characterized by abnormal bone remodeling of the middle and inner ear. In about 50-60% of the patients, the disease is present in a familial form. In most of these families, otosclerosis seems to be caused by a small number of genetic factors (oligogenic) while only in a small number of families the disease seems to be truly monogenic. In the remaining patients a complex genetic form of otosclerosis is present. Several studies have aimed to identify the genetic factors underlying otosclerosis, which has led to the identification of eight published loci for monogenic otosclerosis, as well as several genes and one chromosomal region (11q13.1) with a clear association with otosclerosis. Implementation of next-generation sequencing (NGS) in otosclerosis research has led to the identification of pathogenic variants in MEPE, ACAN and SERPINF1, although the pathogenic role of the latter is under debate. In addition, a recent GWAS can be considered a breakthrough for otosclerosis as it identified several strong associations with otosclerosis and suggested new potential candidate genes. These recent findings are important for unraveling the genetic architecture of otosclerosis. More future studies will help to understand the complete pathogenesis of the disease.
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6
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Højland AT, Tavernier LJM, Schrauwen I, Sommen M, Topsakal V, Schatteman I, Dhooge I, Huber A, Zanetti D, Kunst HPM, Hoischen A, Petersen MB, Van Camp G, Fransen E. A wide range of protective and predisposing variants in aggrecan influence the susceptibility for otosclerosis. Hum Genet 2021; 141:951-963. [PMID: 34410490 DOI: 10.1007/s00439-021-02334-8] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2021] [Accepted: 08/04/2021] [Indexed: 12/16/2022]
Abstract
In this study, we investigated the association of ACAN variants with otosclerosis, a frequent cause of hearing loss among young adults. We sequenced the coding, 5'-UTR and 3'-UTR regions of ACAN in 1497 unrelated otosclerosis cases and 1437 matched controls from six different subpopulations. The association between variants in ACAN and the disease risk was tested through single variant and gene-based association tests. After correction for multiple testing, 14 variants were significantly associated with otosclerosis, ten of which represented independent association signals. Eight variants showed a consistent association across all subpopulations. Allelic odds ratios of the variants identified four predisposing and ten protective variants. Gene-based tests showed an association of very rare variants in the 3'-UTR with the phenotype. The associated exonic variants are all located in the CS domain of ACAN and include both protective and predisposing variants with a broad spectrum of effect sizes and population frequencies. This includes variants with strong effect size and low frequency, typical for monogenic diseases, to low effect size variants with high frequency, characteristic for common complex traits. This single-gene allelic spectrum with both protective and predisposing alleles is unique in the field of complex diseases. In conclusion, these findings are a significant advancement to the understanding of the etiology of otosclerosis.
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Affiliation(s)
- Allan Thomas Højland
- Department of Clinical Medicine, Aalborg University, Aalborg, Denmark.,Research and Knowledge Center in Sensory Genetics, Department of Clinical Genetics, Aalborg University Hospital, Aalborg, Denmark
| | - Lisse J M Tavernier
- Center of Medical Genetics, University of Antwerp and Antwerp University Hospital, Antwerp, Belgium
| | - Isabelle Schrauwen
- Center for Statistical Genetics, Department of Neurology, Gertrude H. Sergievsky Center, Columbia University Medical Center, New York, NY, USA
| | - Manou Sommen
- Center of Medical Genetics, University of Antwerp and Antwerp University Hospital, Antwerp, Belgium
| | - Vedat Topsakal
- Department of ORL and Head and Neck Surgery, Antwerp University Hospital, University of Antwerp, Edegem, Belgium
| | - Isabelle Schatteman
- European Institute for ORL, St-Augustinus Hospital Antwerp, Antwerp, Belgium
| | - Ingeborg Dhooge
- Department of Otolaryngology, Ghent University Hospital, Ghent, Belgium
| | - Alex Huber
- Department of Otorhinolaryngology, Head and Neck Surgery, University Hospital Zurich, Zurich, Switzerland
| | - Diego Zanetti
- Department of Clinical Sciences and Community Health, Audiology Unit, University of Milan, I.R.C.C.S. Fondazione "Cà Granda", Osp.Le Maggiore Policlinico, Milano, Italy
| | - Henricus P M Kunst
- Department of Otorhinolaryngology, Radboud University Medical Center, Radboud Institute for Health Sciences, Nijmegen, The Netherlands.,Department of Otorhinolaryngology, Maastricht University Medical Centre, Maastricht, The Netherlands
| | - Alexander Hoischen
- Department of Human Genetics, Radboud University Medical Center, Nijmegen, The Netherlands.,Department of Otorhinolaryngology, Hearing and Genes, Radboud University Medical Center, Nijmegen, The Netherlands.,Department of Internal Medicine and Radboud Center for Infectious Diseases (RCI), Radboud University Medical Center, Nijmegen, The Netherlands
| | - Michael B Petersen
- Department of Clinical Medicine, Aalborg University, Aalborg, Denmark.,Research and Knowledge Center in Sensory Genetics, Department of Clinical Genetics, Aalborg University Hospital, Aalborg, Denmark
| | - Guy Van Camp
- Center of Medical Genetics, University of Antwerp and Antwerp University Hospital, Antwerp, Belgium.
| | - Erik Fransen
- Center of Medical Genetics, University of Antwerp and Antwerp University Hospital, Antwerp, Belgium. .,StatUa Center for Statistics, University of Antwerp, Antwerp, Belgium.
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7
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Álvarez FJ, García P, Alonso J, Álvarez S. Evaluation of Gene Variants in TGFB1, SERPINF1 and MEPE in a Spanish Family Affected by Otosclerosis and Tinnitus. BIONATURA 2020. [DOI: 10.21931/rb/20120.05.01.7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
Otosclerosis (OTSC) is a common type of deafness affecting up to 0.4 % of Caucasians. Its familial form is inherited in an autosomal dominant fashion, although to this date, no definitive cause for OTSC has been found. In the development of OTSC, three recent genetic association studies have suggested the participation of particular point mutations and small indels in the TGFB1, SERPINF1, and MEPE genes. Consequently, replicative studies are needed to confirm the role of the proposed mutations in OTSC patients. The goal of this study was to test the presence of the candidate variants described in the genes TGFB1, SERPINF1, and MEPE in a new case of familial OTSC with seven affected individuals. DNA was extracted from saliva samples of a Spanish family with several members affected by OTSC. PCR amplified target regions of some candidate genes, and the products were purified, Sanger-sequenced, and analyzed in silico. The family subject of the study did not carry the candidate variants for OTSC described in the genes TGFB1, SERPINF1, and MEPE, although it cannot be ruled out the involvement of other mutations in genes related to their same signaling pathways. This result highlights the importance of performing replicative studies for complex diseases, such as OTCS, in families of diverse origins. Additionally, a significant association of subjective tinnitus with OTSC has been found in this family, although the link between the two pathologies should be studied further.
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Affiliation(s)
- Francisco J. Álvarez
- Escuela de Ciencias Biológicas e Ingeniería Universidad Yachay Tech Urcuquí, Imbabura 100115 EcuadorEscuela de Ciencias Biológicas e Ingeniería Universidad Yachay Tech Urcuquí, Imbabura 100115 Ecuador
| | - Pedro García
- Área de Genética Departamento de Biología Molecular Universidad de León 24071 León, Spain
| | - Jesús Alonso
- Complejo Asistencial Universitario de León C/Altos de Nava s/n 24080 León, Spain
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8
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Insufficient evidence for a role of SERPINF1 in otosclerosis. Mol Genet Genomics 2019; 294:1001-1006. [PMID: 30968248 DOI: 10.1007/s00438-019-01558-8] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2018] [Accepted: 04/01/2019] [Indexed: 12/12/2022]
Abstract
Otosclerosis is a common form of hearing loss (HL) due to abnormal remodeling of the otic capsule. The genetic causes of otosclerosis remain largely unidentified. Only mutations in a single gene, SERPINF1, were previously published in patients with familial otosclerosis. To unravel the contribution of genetic variation in this gene to otosclerosis, this gene was re-sequenced in a large population of otosclerosis patients and controls. Resequencing of the 5' and 3' UTRs, coding regions, and exon-intron boundaries of SERPINF1 was performed in 1604 unrelated otosclerosis patients and 1538 unscreened controls, and in 62 large otosclerosis families. Our study showed no enrichment of rare variants, stratified by type, in SERPINF1 in patients versus controls. Furthermore, the c.392C > A (p.Ala131Asp) variant, previously reported as pathogenic, was identified in three patients and four controls, not replicating its pathogenic nature. We could also not find evidence for a pathogenic role in otosclerosis for 5' UTR variants in the SERPINF1-012 transcript (ENST00000573763), described as the major transcript in human stapes. Furthermore, no rare variants were identified in the otosclerosis families. This study does not support a pathogenic role for variants in SERPINF1 as a cause of otosclerosis. Therefore, the etiology of the disease remains largely unknown and will undoubtedly be the focus of future studies.
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9
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10
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Ziff JL, Crompton M, Powell HRF, Lavy JA, Aldren CP, Steel KP, Saeed SR, Dawson SJ. Mutations and altered expression of SERPINF1 in patients with familial otosclerosis. Hum Mol Genet 2016; 25:2393-2403. [PMID: 27056980 PMCID: PMC5181625 DOI: 10.1093/hmg/ddw106] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2016] [Revised: 03/24/2016] [Accepted: 03/25/2016] [Indexed: 01/08/2023] Open
Abstract
Otosclerosis is a relatively common heterogenous condition, characterized by abnormal bone remodelling in the otic capsule leading to fixation of the stapedial footplate and an associated conductive hearing loss. Although familial linkage and candidate gene association studies have been performed in recent years, little progress has been made in identifying disease-causing genes. Here, we used whole-exome sequencing in four families exhibiting dominantly inherited otosclerosis to identify 23 candidate variants (reduced to 9 after segregation analysis) for further investigation in a secondary cohort of 84 familial cases. Multiple mutations were found in the SERPINF1 (Serpin Peptidase Inhibitor, Clade F) gene which encodes PEDF (pigment epithelium-derived factor), a potent inhibitor of angiogenesis and known regulator of bone density. Six rare heterozygous SERPINF1 variants were found in seven patients in our familial otosclerosis cohort; three are missense mutations predicted to be deleterious to protein function. The other three variants are all located in the 5′-untranslated region (UTR) of an alternative spliced transcript SERPINF1-012. RNA-seq analysis demonstrated that this is the major SERPINF1 transcript in human stapes bone. Analysis of stapes from two patients with the 5′-UTR mutations showed that they had reduced expression of SERPINF1-012. All three 5′-UTR mutations are predicted to occur within transcription factor binding sites and reporter gene assays confirmed that they affect gene expression levels. Furthermore, RT-qPCR analysis of stapes bone cDNA showed that SERPINF1-012 expression is reduced in otosclerosis patients with and without SERPINF1 mutations, suggesting that it may be a common pathogenic pathway in the disease.
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Affiliation(s)
- Joanna L Ziff
- UCL Ear Institute, University College London, London WC1X 8EE, UK
| | - Michael Crompton
- UCL Ear Institute, University College London, London WC1X 8EE, UK
| | - Harry R F Powell
- Royal National Throat Nose and Ear Hospital, London WC1X 8EE, UK
| | - Jeremy A Lavy
- Royal National Throat Nose and Ear Hospital, London WC1X 8EE, UK
| | | | | | - Shakeel R Saeed
- UCL Ear Institute, University College London, London WC1X 8EE, UK.,Royal National Throat Nose and Ear Hospital, London WC1X 8EE, UK
| | - Sally J Dawson
- UCL Ear Institute, University College London, London WC1X 8EE, UK,
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11
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Souza JCRD, Bento RF, Pereira LV, Ikari L, Souza SR, Della Torre AAG, Fonseca ACDO. Evaluation of Functional Outcomes after Stapes Surgery in Patients with Clinical Otosclerosis in a Teaching Institution. Int Arch Otorhinolaryngol 2016; 20:39-42. [PMID: 26722344 PMCID: PMC4687999 DOI: 10.1055/s-0035-1563540] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2015] [Accepted: 06/28/2015] [Indexed: 11/08/2022] Open
Abstract
Introduction Otosclerosis is a primary disease of the temporal bone that leads to stapes ankylosis. Hearing loss is the main symptom. Treatment includes surgery, medical treatment, and sound amplification therapy alone or in combination. Objective To evaluate the functional outcomes of patients with clinical diagnosis of otosclerosis undergoing primary stapes surgery in a teaching institution. Method Retrospective descriptive study. Results A total of 210 ears of 163 patients underwent stapes surgery. Of the 163 patients, 116 (71.2%) underwent unilateral surgery and 47 (28.8%) underwent bilateral surgery. Six of the 210 operated ears had obliterative otosclerosis. The average preoperative and postoperative air–bone gap was 32.06 and 4.39 dB, respectively. The mean preoperative and postoperative bone conduction threshold was 23.17 and 19.82 dB, respectively. A total of 184 (87.6%) ears had a residual air–bone gap <10 dB, and 196 (93.3%) had a residual air–bone gap ≤15 dB. Two patients (0.95%) had severe sensorineural hearing loss. Conclusion Stapes surgery showed excellent functional hearing outcomes in this study. This surgery may be performed in educational institutions with the supervision of experienced surgeons.
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Affiliation(s)
| | - Ricardo Ferreira Bento
- Department of Otolaryngology, Universidade de São Paulo, School of Medicine, São Paulo, São Paulo, Brazil
| | - Larissa Vilela Pereira
- Department of Otolaryngology, Universidade de São Paulo, School of Medicine, São Paulo, São Paulo, Brazil ; Department of Otolaryngology, Anchieta Hospital, Brasília, DF, Brazil
| | - Liliane Ikari
- Department of Otolaryngology, Universidade de São Paulo, School of Medicine, São Paulo, São Paulo, Brazil
| | - Stephanie Rugeri Souza
- Department of Otolaryngology, Universidade de Mogi das Cruzes, Mogi das Cruzes, São Paulo, Brazil
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12
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Alam I, Koller DL, Cañete T, Blázquez G, Mont-Cardona C, López-Aumatell R, Martínez-Membrives E, Díaz-Morán S, Tobeña A, Fernández-Teruel A, Stridh P, Diez M, Olsson T, Johannesson M, Baud A, Econs MJ, Foroud T. Fine mapping of bone structure and strength QTLs in heterogeneous stock rat. Bone 2015; 81:417-426. [PMID: 26297441 PMCID: PMC4641024 DOI: 10.1016/j.bone.2015.08.013] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/24/2015] [Revised: 08/14/2015] [Accepted: 08/17/2015] [Indexed: 11/26/2022]
Abstract
We previously demonstrated that skeletal structure and strength phenotypes vary considerably in heterogeneous stock (HS) rats. These phenotypes were found to be strongly heritable, suggesting that the HS rat model represents a unique genetic resource for dissecting the complex genetic etiology underlying bone fragility. The purpose of this study was to identify and localize genes associated with bone structure and strength phenotypes using 1524 adult male and female HS rats between 17 to 20 weeks of age. Structure measures included femur length, neck width, head width; femur and lumbar spine (L3-5) areas obtained by DXA; and cross-sectional areas (CSA) at the midshaft, distal femur and femoral neck, and the 5th lumbar vertebra measured by CT. In addition, measures of strength of the whole femur and femoral neck were obtained. Approximately 70,000 polymorphic SNPs distributed throughout the rat genome were selected for genotyping, with a mean linkage disequilibrium coefficient between neighboring SNPs of 0.95. Haplotypes were estimated across the entire genome for each rat using a multipoint haplotype reconstruction method, which calculates the probability of descent at each locus from each of the 8 HS founder strains. The haplotypes were then tested for association with each structure and strength phenotype via a mixed model with covariate adjustment. We identified quantitative trait loci (QTLs) for structure phenotypes on chromosomes 3, 8, 10, 12, 17 and 20, and QTLs for strength phenotypes on chromosomes 5, 10 and 11 that met a conservative genome-wide empiric significance threshold (FDR=5%; P<3×10(-6)). Importantly, most QTLs were localized to very narrow genomic regions (as small as 0.3 Mb and up to 3 Mb), each harboring a small set of candidate genes, both novel and previously shown to have roles in skeletal development and homeostasis.
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Affiliation(s)
- Imranul Alam
- Medicine, Indiana University School of Medicine, IN, USA.
| | - Daniel L Koller
- Medical and Molecular Genetics, Indiana University School of Medicine, IN, USA
| | - Toni Cañete
- Department of Psychiatry and Forensic Medicine, Institute of Neurosciences, School of Medicine, Universitat Autònoma de Barcelona, 08193-Bellaterra, Barcelona, Spain
| | - Gloria Blázquez
- Department of Psychiatry and Forensic Medicine, Institute of Neurosciences, School of Medicine, Universitat Autònoma de Barcelona, 08193-Bellaterra, Barcelona, Spain
| | - Carme Mont-Cardona
- Department of Psychiatry and Forensic Medicine, Institute of Neurosciences, School of Medicine, Universitat Autònoma de Barcelona, 08193-Bellaterra, Barcelona, Spain
| | | | - Esther Martínez-Membrives
- Department of Psychiatry and Forensic Medicine, Institute of Neurosciences, School of Medicine, Universitat Autònoma de Barcelona, 08193-Bellaterra, Barcelona, Spain
| | - Sira Díaz-Morán
- Department of Psychiatry and Forensic Medicine, Institute of Neurosciences, School of Medicine, Universitat Autònoma de Barcelona, 08193-Bellaterra, Barcelona, Spain
| | - Adolf Tobeña
- Department of Psychiatry and Forensic Medicine, Institute of Neurosciences, School of Medicine, Universitat Autònoma de Barcelona, 08193-Bellaterra, Barcelona, Spain
| | - Alberto Fernández-Teruel
- Department of Psychiatry and Forensic Medicine, Institute of Neurosciences, School of Medicine, Universitat Autònoma de Barcelona, 08193-Bellaterra, Barcelona, Spain
| | - Pernilla Stridh
- Clinical Neuroscience, Center for Molecular Medicine, Neuroimmunolgy Unit, Karolinska Institutet, S171 76 Stockholm, Sweden
| | - Margarita Diez
- Clinical Neuroscience, Center for Molecular Medicine, Neuroimmunolgy Unit, Karolinska Institutet, S171 76 Stockholm, Sweden
| | - Tomas Olsson
- Clinical Neuroscience, Center for Molecular Medicine, Neuroimmunolgy Unit, Karolinska Institutet, S171 76 Stockholm, Sweden
| | - Martina Johannesson
- Clinical Neuroscience, Center for Molecular Medicine, Neuroimmunolgy Unit, Karolinska Institutet, S171 76 Stockholm, Sweden
| | - Amelie Baud
- Wellcome Trust Center for Human Genetics, Oxford OX3 7BN, United Kingdom
| | - Michael J Econs
- Medicine, Indiana University School of Medicine, IN, USA; Medical and Molecular Genetics, Indiana University School of Medicine, IN, USA
| | - Tatiana Foroud
- Medical and Molecular Genetics, Indiana University School of Medicine, IN, USA
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The pathophysiology of otosclerosis: Review of current research. Hear Res 2015; 330:51-6. [DOI: 10.1016/j.heares.2015.07.014] [Citation(s) in RCA: 57] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/04/2015] [Revised: 07/10/2015] [Accepted: 07/20/2015] [Indexed: 02/07/2023]
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Abstract
HYPOTHESIS Investigation of differential protein expression will provide clues to pathophysiology in otosclerosis. BACKGROUND Otosclerosis is a bone remodeling disorder limited to the endochondral layer of the otic capsule within the temporal bone. Some authors have suggested an inflammatory etiology for otosclerosis resulting from persistent measles virus infection involving the otic capsule. Despite numerous genetic studies, implication of candidate genes in the otosclerotic process remains elusive. We employed liquid chromatography-mass spectrometry (LC-MS) analysis on formalin-fixed celloidin-embedded temporal bone tissues for postmortem investigation of otosclerosis. METHODS Proteomic analysis was performed using human temporal bones from a patient with severe otosclerosis and a control temporal bone. Sections were dissected under microscopy to remove otosclerotic lesions and normal otic capsule for proteomic analysis. Tandem 2D chromatography mass spectrometry was employed. Data analysis and peptide matching to FASTA human databases was done using SEQUEST and proteome discoverer software. RESULTS TGFβ1 was identified in otosclerosis but not in the normal control temporal bone specimen. Aside from TGFβ1, many proteins and predicted cDNA-encoded proteins were observed, with implications in cell death and/or proliferation pathways, suggesting a possible role in otosclerotic bone remodeling. Immunostaining using TGFβ1 monoclonal revealed marked staining of the spongiotic otosclerotic lesions. CONCLUSIONS Mechanisms involved in cochlear extension of otosclerosis are still unclear, but the implication of TGFβ1 is supported by the present proteomic data and immunostaining results. The established role of TGFβ1 in the chondrogenesis process supports the theory of a reaction targeting the globulae interossei within the otic capsule.
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Priyadarshi S, Ray CS, Biswal NC, Nayak SR, Panda KC, Desai A, Ramchander PV. Genetic association and altered gene expression of osteoprotegerin in otosclerosis patients. Ann Hum Genet 2015; 79:225-37. [PMID: 25998045 DOI: 10.1111/ahg.12118] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2015] [Accepted: 04/08/2015] [Indexed: 12/14/2022]
Abstract
Otosclerosis (OTSC) is a late-onset hearing disorder characterized by increased bone turnover in the otic capsule. Disturbed osteoprotegerin expression has been found in the otosclerotic foci which may have an important role in the pathogenesis of OTSC. To identify the genetic risk factors, we sequenced the coding region and exon-intron boundaries of the OPG gene in 254 OTSC patients and 262 controls. Sequence analysis identified five known polymorphisms c.9C>G, c.30+15C>T, c.400+4C>T, c.768A>G, and c.817+8A>C. Testing of these SNPs revealed sex specific association with c.9C>G in males and c.30+15C>T in females after multiple correction. Furthermore, meta-analysis provided evidence of association of the c.9C>G polymorphism with OTSC. In secondary analysis, we investigated the mRNA expression of OPG and associated genes RANK and RANKL in otosclerotic tissues compared to controls. Expression analysis revealed significantly missing/reduced OPG expression only in otosclerotic tissues. However, the signal sequence polymorphism c.9C>G has shown no effect on OPG mRNA expression. In conclusion, our results suggest that the risk of OTSC is influenced by variations in the OPG gene along with other factors which might regulate its altered expression in otosclerotic tissues. Further research is warranted to elucidate the mechanisms underlying these observations.
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Affiliation(s)
- Saurabh Priyadarshi
- Institute of Life Sciences, Nalco Square, Chandrasekharpur, Bhubaneswar, India
| | - Chinmay Sundar Ray
- Department of Ear, Nose, and Throat (ENT), Shrirama Chandra Bhanj (SCB) Medical College, Cuttack, India
| | - Narayan Chandra Biswal
- Department of Ear, Nose, and Throat (ENT), Shrirama Chandra Bhanj (SCB) Medical College, Cuttack, India
| | - Soumya Ranjan Nayak
- Department of Forensic Medicine & Toxicology (FMT), Shrirama Chandra Bhanj (SCB) Medical College, Cuttack, India
| | | | - Ashim Desai
- Dr. ABR Desai Ear, Nose and Throat (ENT) Clinic and Research Centre, Mumbai, India
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Genetic association analysis in a clinically and histologically confirmed otosclerosis population confirms association with the TGFB1 gene but suggests an association of the RELN gene with a clinically indistinguishable otosclerosis-like phenotype. Otol Neurotol 2015; 35:1058-64. [PMID: 24643032 DOI: 10.1097/mao.0000000000000334] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
BACKGROUND/HYPOTHESIS Otosclerosis is a frequent cause of hearing impairment characterized by abnormal resorption and deposition of bone in the human otic capsule. It is a disease of complex etiopathogenesis that is caused by both environmental and genetic factors. The goal of this study is to replicate association for genes that were previously reported to be associated with otosclerosis. However, in this study, patients were used in which the presence of otosclerotic foci was confirmed by histologic investigation, in contrast to previous studies, that did not use histologic confirmation. METHODS Case-control association study using 153 cases and 300 controls. Thirteen single nucleotide polymorphisms (SNPs) in 6 genes (COL1A1, TGFB1, BMP2, BMP4, AGT, and RELN) were genotyped. RESULTS An association between TGFB1 (rs1800472) and otosclerosis was detected, confirming several previous reports. It is surprising that no association was found between RELN and otosclerosis because the current analysis had very reasonable power and the RELN association has been published before in different articles using several independent populations. CONCLUSION Our findings strengthen the association of TGFB1 (rs1800472) with otosclerosis. The fact that other genes did not replicate could be due to different reasons like lack of power (BMP2 and BMP4) and possible false-positive initial association (COL1A1 and AGT). A plausible explanation for the lack of association for RELN is that RELN could be associated with a specific otosclerosis-like phenotype that is different from the histologically confirmed phenotype of the patients in this study, and that is clinically not distinguishable.
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Abstract
HYPOTHESIS Genetic variation in BMP2 and BMP4 found in otosclerosis patients result in altered Smad signaling. BACKGROUND Otosclerosis is a common form of adult-onset conductive hearing loss resulting from abnormal bone remodeling of the bony labyrinth that surrounds the inner ear. Both genetic and environmental factors are implicated in the disease, yet very little is known about its pathogenesis. The evidence for a genetic component has been established through family-based linkage and population-based association studies. Previously, members of the TGF-β superfamily of genes have been associated with otosclerosis. METHODS Sequencing of BMP2 and BMP4 coding regions was performed to identify common and rare variation in German otosclerosis patients compared with controls. Functional analyses of rare variation in the patient cohort were conducted by exposing an osteosarcoma cell line to conditioned media containing either wild type or variant forms of BMP2 or BMP4 and analyzing Smad1/5/8 phosphorylation. RESULTS Although no significant association with common variation in these 2 genes was detected, there were 8 singleton variants identified in the German population. Of the 4 coding variants found solely in otosclerosis patients, two--BMP4(N150K) and BMP2(K357-R396del)--were found to decrease Smad1/5/8 signaling. CONCLUSION Rare variants in BMP2 and BMP4 are not a major genetic component in the otosclerosis population. However, those with functional affect showed decreased Smad signaling. Further analysis of Smad signaling molecules should be performed to determine if these pathways in combination are a major contributor to otosclerosis, which could lead to additional treatment options for otosclerosis patients.
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Exclusion of TNFRSF11B as Candidate Gene for Otosclerosis in Campania Population. Indian J Otolaryngol Head Neck Surg 2014; 66:297-301. [PMID: 25032118 DOI: 10.1007/s12070-014-0706-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2013] [Accepted: 01/20/2014] [Indexed: 10/25/2022] Open
Abstract
The etiology of otosclerosis is unknown. The etiopathogenesis of otosclerosis seems similar to that occurring in Paget's disease of bone, for which mutations or polymorphisms in several genes have been identified. Among these, TNFRSF11B gene encoding the osteoprotegerin is produced at high levels in the normal inner ear and at low level in active otosclerotic stapes footplates. The aim of this work was to verify the presence of a correlation between the rs2073618 (N3K) polymorphism in the TNFRSF11B gene and otosclerosis. Mutational screening in the TNFRSF11B gene was performed by direct sequencing. SNPs analysis was performed by PCR and by specific restriction enzyme assay with HpaI. The significance of the association was analyzed by statistical specific software. No causative mutation has been identified but the data suggested a strong correlation between the rs2073618 (N3K) polymorphism and otosclerosis. This correlation, however, has been excluded in a case-control study. This study excluded the association between the N3K polymorphism and otosclerosis in Campania region population.
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Priyadarshi S, Ray CS, Panda KC, Desai A, Nayak SR, Biswal NC, Ramchander PV. Genetic association and gene expression profiles of TGFB1 and the contribution of TGFB1 to otosclerosis susceptibility. J Bone Miner Res 2013; 28:2490-7. [PMID: 23703862 DOI: 10.1002/jbmr.1991] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/05/2013] [Revised: 04/25/2013] [Accepted: 05/15/2013] [Indexed: 12/15/2022]
Abstract
Otosclerosis (OTSC) is a common form of acquired hearing loss resulting from disturbed bone remodeling in the otic capsule of the middle ear. Transforming growth factor-beta1 (TGFB1) produced by osteoblasts is the most abundant growth factor in human bone. Previous studies have shown the contribution of single-nucleotide polymorphisms (SNPs) in TGFB1 toward the risk of developing OTSC in some ethnic populations. The present study was aimed at investigating the genetic association and expression profiles of TGFB1 in OTSC patients. Two SNPs (c.-800G > A and c.-509C > T) in the promoter region and three SNPs (c.29T > C, c.74G > C, and c.788C > T) in the coding region were genotyped in 170 cases and 170 controls. The genetic association analysis revealed the significant association between c.-509C > T (p = 0.0067; odds ratio [OR] = 1.562; 95% confidence interval [CI], 1.140-2.139) and OTSC. The increased minor allele "T" frequency in cases (0.42) compared to controls (0.31) indicates its possible role in the etiology of the disease. The minor allele frequencies for the SNPs c.-800G > A, c.29T > C, and c.74G >C were similar among the cases (0.04, 0.47, and 0.08, respectively) and controls (0.05, 0.42, 0.07, respectively). We found that c.788C > T was monomorphic in this population. Interestingly, a four-locus haplotype (G-T-T-G) from these SNPs was found to be significantly associated with OTSC (p = 0.0077). We identified a de novo heterozygous mutation c.-832G > A in the promoter region of TGFB1 in 1 patient. In a secondary analysis, we investigated the possibility of abnormal TGFB1 expression and irregular bone growth in OTSC by expression analysis of TGFB1 mRNA in disease tissue compared to control. We found relatively increased expression of TGFB1 mRNA in the stapes tissues of cases compared to controls (p = 0.0057). In conclusion, this study identified a risk variant c.-509C > T and a risk haplotype G-T-T-G in the TGFB1 gene that contribute toward the susceptibility to OTSC.
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Bel Hadj Ali I, Ben Saida A, Beltaief N, Namouchi I, Besbes G, Ghazoueni E, Ben Arab S. HLA class I polymorphisms in Tunisian patients with otosclerosis. Ann Hum Biol 2012; 39:190-4. [DOI: 10.3109/03014460.2012.671849] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Affiliation(s)
- Insaf Bel Hadj Ali
- Unité d'Epidémiologie Génétique et Moléculaire, Faculté de Médecine de Tunis, Tunisia
| | - Asma Ben Saida
- Unité d'Epidémiologie Génétique et Moléculaire, Faculté de Médecine de Tunis, Tunisia
| | - Najeh Beltaief
- Unité d'Epidémiologie Génétique et Moléculaire, Faculté de Médecine de Tunis, Tunisia
- Service ORL et de Chirurgie Maxillo-faciale, Hôpital La Rabta de Tunis, Tunisia
| | - Imen Namouchi
- Unité d'Epidémiologie Génétique et Moléculaire, Faculté de Médecine de Tunis, Tunisia
| | - Ghazi Besbes
- Service ORL et de Chirurgie Maxillo-faciale, Hôpital La Rabta de Tunis, Tunisia
| | - Ezzeddine Ghazoueni
- Laboratoire d'Immunologie, Hôpital Militaire Principal d'Instruction de Tunis, Tunisia
| | - Saida Ben Arab
- Unité d'Epidémiologie Génétique et Moléculaire, Faculté de Médecine de Tunis, Tunisia
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Dahlin Redfors Y, Möller C. Otosclerosis: Thirty-Year Follow-Up After Surgery. Ann Otol Rhinol Laryngol 2011; 120:608-14. [DOI: 10.1177/000348941112000909] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Objectives: The aims of this study were to evaluate the hearing outcomes 28 to 30 years after stapedectomy in patients with surgically confirmed otosclerosis, and to evaluate inner ear involvement. Methods: A retrospective clinical study was performed. Sixty-five consecutive patients who underwent stapedectomy at a tertiary referral center between 1977 and 1979 were included in the study. Medical records, including preoperative and postoperative audiograms, were reviewed, and a long-term follow-up clinical examination and pure tone audiometry were performed. The hearing outcome was compared with that of a reference population (ISO 7029) in terms of age and gender. Results: Thirty years after stapedectomy, 66% of the patients' ears studied showed a moderate to profound hearing loss. The deterioration was mainly caused by a sensory hearing loss. The hearing loss was significantly greater than that in the reference population for both air and bone conduction thresholds at the early and late stages of the disease. A large majority of the patients (88%) had bilateral otosclerosis. Conclusions: Patients with otosclerosis have a sensorineural hearing loss that cannot be explained by age. Otosclerosis should be regarded as a middle and inner ear disease. Almost all patients with otosclerosis are in need of ongoing audio-logical rehabilitation and hearing aids.
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Affiliation(s)
- Ylva Dahlin Redfors
- Department of Otolaryngology, Department of Clinical Sciences, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
- Department of Audiology, Örebro University Hospital, School of Health Science, Örebro University/Swedish Institute of Disability Research, Örebro, Sweden
| | - Claes Möller
- Department of Audiology, Örebro University Hospital, School of Health Science, Örebro University/Swedish Institute of Disability Research, Örebro, Sweden
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Khalfallah A, Schrauwen I, Mnejja M, HadjKacem H, Dhouib L, Mosrati MA, Hakim B, Lahmar I, Charfeddine I, Driss N, Ayadi H, Ghorbel A, Van Camp G, Masmoudi S. Association of COL1A1 and TGFB1 Polymorphisms with Otosclerosis in a Tunisian Population. Ann Hum Genet 2011; 75:598-604. [DOI: 10.1111/j.1469-1809.2011.00665.x] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Csomor P, Sziklai I, Karosi T. Controversies in RELN/reelin expression in otosclerosis. Eur Arch Otorhinolaryngol 2011; 269:431-40. [DOI: 10.1007/s00405-011-1653-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2011] [Accepted: 05/20/2011] [Indexed: 01/02/2023]
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Schrauwen I, Weegerink NJD, Fransen E, Claes C, Pennings RJE, Cremers CWRJ, Huygen PLM, Kunst HPM, Van Camp G. A new locus for otosclerosis, OTSC10, maps to chromosome 1q41-44. Clin Genet 2011; 79:495-7. [DOI: 10.1111/j.1399-0004.2010.01576.x] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Abstract
PURPOSE OF REVIEW The aim of this study is to summarize current advances in research and clinical aspects of cochlear otosclerosis. RECENT FINDINGS Recent studies have revealed that otosclerosis is a process of bone remodeling that is unique to the otic capsule only. Even though no obvious bone remodeling is seen in the otic capsule under normal conditions, remodeling starts when some molecular factors trigger the capsule in certain patients who have genetic and/or environmental tendencies. SUMMARY Cochlear otosclerosis is defined as otosclerosis located in the otic capsule involving the cochlear endosteum and causing sensorineural hearing loss or mixed-type hearing loss. It has been clearly shown that, when otosclerosis is sufficiently severe to involve the cochlear endosteum, it usually fixes the stapes as well.
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Khalfallah A, Schrauwen I, Mnaja M, Fransen E, Lahmar I, Ealy M, Dhouib L, Ayadi H, Charfedine I, Driss N, Ghorbel A, Smith RJ, Masmoudi S, Van Camp G. Genetic variants in RELN are associated with otosclerosis in a non-European population from Tunisia. Ann Hum Genet 2010; 74:399-405. [DOI: 10.1111/j.1469-1809.2010.00595.x] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
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Schrauwen I, Van Camp G. The etiology of otosclerosis: a combination of genes and environment. Laryngoscope 2010; 120:1195-202. [PMID: 20513039 DOI: 10.1002/lary.20934] [Citation(s) in RCA: 65] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Otosclerosis is a common form of hearing loss characterized by abnormal bone remodeling in the otic capsule. It is a complex genetic disease, caused by a combination of genetic and environmental factors. During the past decade, several attempts have been made to identify factors for otosclerosis. This review provides an overview of the current understanding of the etiology of otosclerosis and describes the genetic and environmental factors that have been implicated in the disease. Environmental factors include fluoride and viral factors, particularly measles. Genetic association studies for otosclerosis have reported several associations of genetic variants that influence the risk of disease, mainly involving bone remodeling pathways, although their individual risk contributions are small. Rare monogenic forms of otosclerosis also exist, which are caused by a mutation in a single gene leading to a clear familial segregation of the disease. Linkage analysis of large otosclerosis families has led to the identification of seven loci, and recently evidence was found that T cell receptor beta is a gene responsible for familial otosclerosis, suggesting an underlying immunological pathway. However, this might also represent an autoimmune process, a hypothesis that is supported by other data as well. In conclusion, a variety of pathways have been identified to be involved in the development of otosclerosis, showing that distinct mechanisms involving both genetic and environmental risk factors can influence and contribute to a similar disease outcome.
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Ealy M, Smith RJ. The Genetics of otosclerosis. Hear Res 2010; 266:70-4. [DOI: 10.1016/j.heares.2009.07.002] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/08/2009] [Revised: 07/03/2009] [Accepted: 07/06/2009] [Indexed: 11/15/2022]
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Etiopathogenesis of otosclerosis. Eur Arch Otorhinolaryngol 2010; 267:1337-49. [DOI: 10.1007/s00405-010-1292-1] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2010] [Accepted: 05/20/2010] [Indexed: 10/19/2022]
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Involvement of T-cell receptor-beta alterations in the development of otosclerosis linked to OTSC2. Genes Immun 2010; 11:246-53. [PMID: 20182450 DOI: 10.1038/gene.2010.3] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Otosclerosis is a common form of hearing loss, characterized by disordered bone remodeling in the otic capsule. Within the otosclerotic foci, several immunocompetent cells and immune-modulating factors can be found. Different etiological theories involving the immune system have been suggested. However, a genetic component is clearly present. In large otosclerosis families, seven autosomal-dominant loci have been found, but none of the disease-causing genes has been identified. This study focused on the exploration of the second otosclerosis locus on chromosome 7q34-36 (OTSC2), holding the T-cell receptor beta locus (TRB locus). A significantly lower T-cell receptor-beta (TCR-beta) mRNA expression and percentage of blood circulating TCR-alphabeta(+) T cells was detected in OTSC2 patients compared with controls and patients with the complex form of the disease. Further analysis illustrated more significant disturbances in specific T-cell subsets, including an increased CD28(null) cell population, suggesting a disturbed T-cell development and ageing in OTSC2 patients. These disturbances could be associated with otosclerotic bone remodeling, given the known effects of immunocompetent cells on bone physiology. These data implicate the TRB locus as the causative gene in the OTSC2 region and represent an important finding in the elucidation of the disease pathology.
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Abstract
OBJECTIVES Otosclerosis is a major cause of acquired hearing loss in adult life affecting exclusively the human temporal bone. Until recently, the etiopathogenesis of otosclerosis was still a matter of debate. Genetic research, however, has evolved enormously the last years and unveiled important clues regarding the cause of otosclerosis. The objective of this article is to review the genetics of otosclerosis with special attention for the links to the bone homeostasis of the otic capsule. DATA SOURCES A detailed literature study was performed focusing on the recent genetic findings in otosclerosis and the special bone turnover of the otic capsule. A PubMed search and own research data were used to bring the relevant information for this review together. CONCLUSION Unlike all other bones in the human skeleton, the otic capsule undergoes very little remodeling after development, possibly due to local inner ear factors. Otosclerosis is a process of pathologic increased bone turnover in the otic capsule, which in most cases leads to stapes fixation, resulting in a conductive hearing loss. Although environmental factors such as estrogens, fluoride, and viral infection have been implicated, it is clear that genetic factors play a significant role in the manifestation of otosclerosis. From a genetic viewpoint, otosclerosis is considered to be a complex disease with rare autosomal dominant forms caused by a single gene. Already, 7 monogenic loci have been published, but none of the genes involved have been identified. For the complex form of otosclerosis, caused by an interaction between genetic and environmental factors, the first susceptibility genes were identified by case-control association studies. All 3 replicated genes, TGFB1, BMP2, and BMP4, are a part of the transforming growth factor-beta1 pathway. Data from both genetic association studies and gene expression analysis of otosclerotic bone showed that the TGF-beta1 pathway is most likely an important factor in the pathogenesis of otosclerosis.
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No Evidence for Association Between the Renin-Angiotensin-Aldosterone System and Otosclerosis in a Large Belgian-Dutch Population. Otol Neurotol 2009; 30:1079-83. [DOI: 10.1097/mao.0b013e3181ab3058] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
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Genetic variants in the RELN gene are associated with otosclerosis in multiple European populations. Hum Genet 2009; 127:155-62. [DOI: 10.1007/s00439-009-0754-2] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2009] [Accepted: 10/12/2009] [Indexed: 10/20/2022]
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Sziklai I, Batta TJ, Karosi T. Otosclerosis: an organ-specific inflammatory disease with sensorineural hearing loss. Eur Arch Otorhinolaryngol 2009; 266:1711-8. [PMID: 19340443 DOI: 10.1007/s00405-009-0967-y] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2008] [Accepted: 03/17/2009] [Indexed: 12/20/2022]
Abstract
Otosclerosis is an inflammatory disease associated with persistent measles virus (MV) infection of the otic capsule. The nature of sensorineural hearing loss (SNHL) related to otosclerosis can be due to the chronic TNF-alpha release from the foci. TNF-alpha enters the inner ear fluid spaces in histologically active stages of otosclerosis and may cause outer hair cell functional disorder and subsequent SNHL without morphological changes of the organ of Corti. On the contrary, non-otosclerotic stapes ankylosis being a non-inflammatory disease is not harmful for hair cells. Theoretically, SNHL should not associate to this type of stapes fixation. Stapes footplates (N = 248) were examined by hematoxylin-eosin staining and corresponding MV-, OPG- and TNF-alpha-specific RT-PCR. Anti-measles IgG levels of serum specimens were measured by ELISA. Preoperative audiological results were correlated with otosclerotic and non-otosclerotic histopathologies. Among patients with stapes fixation, we found 93 active and 67 inactive otosclerosis, and 88 non-otosclerotic stapes ankylosis. MV could only be detected in otosclerotic stapes footplates. Audiometry revealed bone conduction threshold elevation toward the high frequencies in otosclerotic patients, which was associated to the duration of hearing loss. OPG mRNA expression was significantly lower in the TNF-alpha positive specimens, which was independent from virus positivity. In about one-third of stapes fixations, the etiology is non-otosclerotic stapes ankylosis. Histologic otosclerosis exhibits a strong correlation with MV presence in the bone as a sign of persistent MV infection and related inflammation with TNF-alpha release. This causes SNHL in the function of time. Non-otosclerotic stapes fixations do not cause high-frequency SNHL.
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Affiliation(s)
- István Sziklai
- Department of Otorhinolaryngology, Head and Neck Surgery, Medical and Health Science Center, University of Debrecen, Debrecen, Hungary
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Thys M, Schrauwen I, Vanderstraeten K, Dieltjens N, Fransen E, Ealy M, Cremers CWRJ, van de Heyning P, Vincent R, Offeciers E, Smith RH, van Camp G. Detection of Rare Nonsynonymous Variants inTGFB1in Otosclerosis Patients. Ann Hum Genet 2009; 73:171-5. [DOI: 10.1111/j.1469-1809.2009.00505.x] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Schrauwen I, Ealy M, Huentelman MJ, Thys M, Homer N, Vanderstraeten K, Fransen E, Corneveaux JJ, Craig DW, Claustres M, Cremers CW, Dhooge I, Van de Heyning P, Vincent R, Offeciers E, Smith RJ, Van Camp G. A genome-wide analysis identifies genetic variants in the RELN gene associated with otosclerosis. Am J Hum Genet 2009; 84:328-38. [PMID: 19230858 DOI: 10.1016/j.ajhg.2009.01.023] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2008] [Revised: 01/12/2009] [Accepted: 01/30/2009] [Indexed: 11/25/2022] Open
Abstract
Otosclerosis is a common form of progressive hearing loss, characterized by abnormal bone remodeling in the otic capsule. The etiology of the disease is largely unknown, and both environmental and genetic factors have been implicated. To identify genetic factors involved in otosclerosis, we used a case-control discovery group to complete a genome-wide association (GWA) study with 555,000 single-nucleotide polymorphisms (SNPs), utilizing pooled DNA samples. By individual genotyping of the top 250 SNPs in a stepwise strategy, we were able to identify two highly associated SNPs that replicated in two additional independent populations. We then genotyped 79 tagSNPs to fine map the two genomic regions defined by the associated SNPs. The region with the strongest association signal, p(combined) = 6.23 x 10(-10), is on chromosome 7q22.1 and spans intron 1 to intron 4 of reelin (RELN), a gene known for its role in neuronal migration. Evidence for allelic heterogeneity was found in this region. Consistent with the GWA data, expression of RELN was confirmed in the inner ear and in stapes footplate specimens. In conclusion, we provide evidence that implicates RELN in the pathogenesis of otosclerosis.
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An overview of the etiology of otosclerosis. Eur Arch Otorhinolaryngol 2008; 266:25-35. [PMID: 18704474 DOI: 10.1007/s00405-008-0790-x] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2008] [Accepted: 07/29/2008] [Indexed: 10/21/2022]
Abstract
Otosclerosis is the primary disease affecting the homeostasis of otic capsule and is among the most common causes of acquired hearing loss. Otosclerosis is considered as a multifactor disease, caused by both genetic and environmental factors. The aim of the present review is to summarize and analyze the bibliographic data, associated with the etiology of the disease. In some cases, the otosclerosis has an autosomal dominant mode of inheritance with incomplete penetrance. Genetic studies reveal the occurrence of at least nine chromosomal loci as candidate genes of the disease. The localized measles virus infection of the otic capsule has been postulated as a possible etiological theory. The role of hormonal factors, immune and bone-remodeling system in the etiopathogenesis of otosclerosis and the association of the disease with the disorders of the connective tissue are the issues of the present study. Despite the extensive research, many etiological factors and theories have been suggested and the process of development of the otosclerosis remains unclear.
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Abstract
UNLABELLED We studied the role of polymorphisms in 13 candidate genes on the risk of otosclerosis in two large independent case-control sets. We found significant association in both populations with BMP2 and BMP4, implicating these two genes in the pathogenesis of this disease. INTRODUCTION Otosclerosis is a progressive disorder of the human temporal bone that leads to conductive hearing loss and in some cases sensorineural or mixed hearing loss. In a few families, it segregates as a monogenic disease with reduced penetrance, but in most patients, otosclerosis is more appropriately considered a complex disorder influenced by genetic and environmental factors. MATERIALS AND METHODS To identify major genetic factors in otosclerosis, we used a candidate gene approach to study two large independent case-control sets of Belgian-Dutch and French origin. Tag single nucleotide polymorphisms (SNPs) in 13 candidate susceptibility genes were studied in a stepwise strategy. RESULTS Two SNPs were identified that showed the same significant effect in both populations. The first SNP, rs3178250, is located in the 3' untranslated region of BMP2. Individuals homozygote for the C allele are protected against otosclerosis (combined populations: p = 2.2 x 10(-4); OR = 2.027; 95% CI = 1.380-2.979). The second SNP, rs17563, is an amino acid changing (p.Ala152Val) SNP located in BMP4. The G allele, coding for the amino acid alanine, confers susceptibility in both populations (combined populations: p = 0.002; OR = 1.209; 95% CI: 1.070-1.370). CONCLUSIONS These results indicate that polymorphisms in the BMP2 and BMP4 genes, both members of the TGF-beta superfamily, contribute to the susceptibility to otosclerosis and further strengthen the results from the recently reported association of TGFB1 with this disease.
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Ealy M, Chen W, Ryu GY, Yoon JG, Welling DB, Hansen M, Madan A, Smith RJH. Gene expression analysis of human otosclerotic stapedial footplates. Hear Res 2008; 240:80-6. [PMID: 18430532 DOI: 10.1016/j.heares.2008.03.001] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/17/2007] [Revised: 03/10/2008] [Accepted: 03/11/2008] [Indexed: 12/31/2022]
Abstract
Otosclerosis is a complex disease that results in a common form of conductive hearing loss due to impaired mobility of the stapes. Stapedial motion becomes compromised secondary to invasion of otosclerotic foci into the stapedio-vestibular joint. Although environmental factors and genetic causes have been implicated in this process, the pathogenesis of otosclerosis remains poorly understood. To identify molecular contributors to otosclerosis we completed a microarray study of otosclerotic stapedial footplates. Stapes footplate samples from otosclerosis and control patients were used in the analysis. One-hundred-and-ten genes were found to be differentially expressed in otosclerosis samples. Ontological analysis of differentially expressed genes in otosclerosis provides evidence for the involvement of a number of pathways in the disease process that include interleukin signaling, inflammation and signal transduction, suggesting that aberrant regulation of these pathways leads to abnormal bone remodeling. Functional analyses of genes from this study will enhance our understanding of the pathogenesis of this disease.
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Affiliation(s)
- Megan Ealy
- Molecular Otolaryngology Research Laboratories, Department of Otolaryngology, Pediatrics and Internal Medicine, Division of Nephrology, 200 Hawkins Drive - 21151 PFP, University of Iowa, Iowa City, IA, USA
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Bel Hadj Ali I, Thys M, Beltaief N, Schrauwen I, Hilgert N, Vanderstraeten K, Dieltjens N, Mnif E, Hachicha S, Besbes G, Ben Arab S, Van Camp G. A new locus for otosclerosis, OTSC8, maps to the pericentromeric region of chromosome 9. Hum Genet 2008; 123:267-72. [DOI: 10.1007/s00439-008-0470-3] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2007] [Accepted: 01/14/2008] [Indexed: 10/22/2022]
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Abstract
BACKGROUND The aetiology of otosclerosis is not fully understood despite intensive research. It is, however, certain that a genetic component plays a significant role in the manifestation of otosclerosis, although the precise mode of inheritance is still uncertain. OBJECTIVE OF REVIEW To provide an up-to-date review for the genetics of otosclerosis. The mode of inheritance, chromosomal and linkage studies are presented. In addition, the possible genetic relationship between otosclerosis and osteogenesis imperfecta, and the association between otosclerosis and specific human leucocyte antigen types are described. TYPE OF REVIEW Systematic analysis of the literature was focused on any information related to the genetics of otosclerosis. SEARCH STRATEGY A MEDLINE search (1960-2007) was undertaken to perform a comprehensive review. Articles were also identified through searches of the files of authors. RESULTS The majority of epidemiological studies on families with otosclerosis suggest an autosomal dominant mode of inheritance with reduced penetrance of approximately 40%. Genetic linkage studies have demonstrated the presence of six loci (OTSC1, OTSC2, OTSC3, OTSC4, OTSC5 and OTSC7) located on chromosomes 15q, 7q, 6p, 16q, 3q and 6q respectively. Although these loci have been mapped, no causative genes have been identified, and we have little idea of the molecular process involved in this disease. While clinical similarities and some unreplicated genetic association studies suggest an aetiological relationship between otosclerosis and osteogenesis imperfecta-type I, there is no definite evidence of a common pathological process between the two diseases. CONCLUSIONS Otosclerosis may be considered as a complex disease with relatively common monogenic forms. Knowledge of these genes could lead to substantial improvements in our ability to diagnose and possibly even prevent or treat this type of hearing deterioration.
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Affiliation(s)
- I Moumoulidis
- Department of Otolaryngology, University of Cambridge, Addenbrooke's Hospital, Hills Road, Cambridge, UK.
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Pauw RJ, Huygen PLM, Thys M, Van Camp G, Joosten FBM, Cremers CWRJ. Phenotype description of a Dutch otosclerosis family with suggestive linkage toOTSC7. Am J Med Genet A 2007; 143A:1613-22. [PMID: 17568406 DOI: 10.1002/ajmg.a.31807] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
This study reports on a clinical investigation of a Dutch family that shows suggestive linkage to OTSC7. Cross-sectional as well as longitudinal analyses of audiometric data were performed. Also, high-resolution computed tomography (CT) images of the temporal bones from genetically affected family members were obtained to study the incidence and extent of otospongiotic foci. Audiometric data showed a considerable degree of phenotypic variability. Cross-sectional regression analysis did not show age-dependent progression of bone conduction (BC), air conduction (AC), and air-bone gap (ABG) levels. Longitudinal analysis of audiometric follow-up data of one family member showed age-dependent progression of AC, BC, and ABG levels. High-resolution CT images revealed an otospongiotic focus in six of six (100%) clinically affected individuals that carried the disease haplotype. In none of the clinically unaffected family members that showed linkage to OTSC7, an otospongiotic focus was detected by CT. In conclusion, hearing impairment in the present otosclerosis family seems to be variable in terms of onset age and level of progression. Long-term audiometric data of one patient proved to be valuable in understanding progression of hearing impairment in this individual. The detection rate of otospongiotic foci in our study group is similar compared to previous reports on CT data in consecutive otosclerosis patients who had stapes replacing surgery.
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Affiliation(s)
- Robert Jan Pauw
- Department of Otorhinolaryngology, Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands.
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Thys M, Schrauwen I, Vanderstraeten K, Janssens K, Dieltjens N, Van Den Bogaert K, Fransen E, Chen W, Ealy M, Claustres M, Cremers CRWJ, Dhooge I, Declau F, Claes J, Van de Heyning P, Vincent R, Somers T, Offeciers E, Smith RJH, Van Camp G. The coding polymorphism T263I in TGF-β1 is associated with otosclerosis in two independent populations. Hum Mol Genet 2007; 16:2021-30. [PMID: 17588962 DOI: 10.1093/hmg/ddm150] [Citation(s) in RCA: 61] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Otosclerosis is a progressive hearing loss characterized by an abnormal bone homeostasis of the otic capsule that leads to stapes fixation. Although its etiology remains unknown, otosclerosis can be considered a complex disease. Transforming growth factor-beta 1 (TGF-beta1) was chosen for a case-control association study, because of several non-genetic indications of involvement in otosclerosis. Single nucleotide polymorphism (SNP) analysis in a large Belgian-Dutch sample set gave significant results (P = 0.0044) for an amino acid changing SNP, T263I. Analysis of an independent French population replicated this association with SNP T263I (P = 0.00019). The results remained significant after multiple testing correction in both populations. Haplotype analysis and the results of an independent effect test using the weighted haplotype (WHAP) computer program in both populations were both compatible with SNP T263I being the only causal variant. The variant I263 is under-represented in otosclerosis patients and hence protective against the disease. Combining the data of both case-control groups for SNP T263I with a Mantel-Haenszel estimate of common odds ratios gave a very significant result (P = 9.2 x 10(-6)). Functional analysis of SNP T263I with a luciferase reporter assay showed that the protective variant I263 of TGF-beta1 is more active than the WT variant T263 (P = 1.6 x 10(-6)). On the basis of very low P-values, replication in an independent population and a functional effect of the protective variant, we conclude that TGF-beta1 influences the susceptibility for otosclerosis, and that the I263 variant is protective against the disease.
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Affiliation(s)
- Melissa Thys
- Department of Medical Genetics, University of Antwerp, Antwerp, Belgium
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