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Verdoodt D, van Wijk E, Broekman S, Venselaar H, Aben F, Sels L, De Backer E, Gommeren H, Szewczyk K, Van Camp G, Ponsaerts P, Van Rompaey V, de Vrieze E. Rational design of a genomically humanized mouse model for dominantly inherited hearing loss, DFNA9. Hear Res 2024; 442:108947. [PMID: 38218018 DOI: 10.1016/j.heares.2023.108947] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/09/2023] [Revised: 12/04/2023] [Accepted: 12/30/2023] [Indexed: 01/15/2024]
Abstract
DFNA9 is a dominantly inherited form of adult-onset progressive hearing impairment caused by mutations in the COCH gene. COCH encodes cochlin, a crucial extracellular matrix protein. We established a genomically humanized mouse model for the Dutch/Belgian c.151C>T founder mutation in COCH. Considering upcoming sequence-specific genetic therapies, we exchanged the genomic murine Coch exons 3-6 for the corresponding human sequence. Introducing human-specific genetic information into mouse exons can be risky. To mitigate unforeseen consequences on cochlin function resulting from the introduction of the human COCH protein-coding sequence, we converted all human-specific amino acids to mouse equivalents. We furthermore optimized the recognition of the human COCH exons by the murine splicing machinery during pre-mRNA splicing. Subsequent observations in mouse embryonic stem cells revealed correct splicing of the hybrid Coch transcript. The inner ear of the established humanized Coch mice displays correctly-spliced wild-type and mutant humanized Coch alleles. For a comprehensive study of auditory function, mice were crossbred with C57BL/6 Cdh23753A>G mice to remove the Cdh23ahl allele from the genetic background of the mice. At 9 months, all humanized Coch genotypes showed hearing thresholds comparable to wild-type C57BL/6 Cdh23753A>G mice. This indicates that both the introduction of human wildtype COCH, and correction of Cdh23ahl in the humanized Coch lines was successful. Overall, our approach proved beneficial in eliminating potential adverse events of genomic humanization of mouse genes, and provides us with a model in which sequence-specific therapies directed against the human mutant COCH alle can be investigated. With the hearing and balance defects anticipated to occur late in the second year of life, a long-term follow-up study is ongoing to fully characterize the humanized Coch mouse model.
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Affiliation(s)
- Dorien Verdoodt
- Department of Translational Neurosciences, Faculty of Medicine and Health Sciences, University of Antwerp, Antwerp, Belgium; Laboratory of Experimental Hematology, Vaccine and Infectious Disease Institute (Vaxinfectio), University of Antwerp, Antwerp, Belgium
| | - Erwin van Wijk
- Department of Otorhinolaryngology, Hearing and Genes, Radboud University Medical Center, Nijmegen, GA 6525, the Netherlands
| | - Sanne Broekman
- Department of Otorhinolaryngology, Hearing and Genes, Radboud University Medical Center, Nijmegen, GA 6525, the Netherlands
| | - Hanka Venselaar
- Department of Medical BioSciences, Radboud University Medical Center, Nijmegen, GA 6525, the Netherlands
| | - Fien Aben
- Department of Translational Neurosciences, Faculty of Medicine and Health Sciences, University of Antwerp, Antwerp, Belgium; Department of Otorhinolaryngology, Hearing and Genes, Radboud University Medical Center, Nijmegen, GA 6525, the Netherlands
| | - Lize Sels
- Department of Translational Neurosciences, Faculty of Medicine and Health Sciences, University of Antwerp, Antwerp, Belgium
| | - Evi De Backer
- Department of Translational Neurosciences, Faculty of Medicine and Health Sciences, University of Antwerp, Antwerp, Belgium; Department of Otorhinolaryngology and Head & Neck Surgery, Antwerp University Hospital, Antwerp, Belgium
| | - Hanne Gommeren
- Department of Translational Neurosciences, Faculty of Medicine and Health Sciences, University of Antwerp, Antwerp, Belgium
| | - Krystyna Szewczyk
- Department of Translational Neurosciences, Faculty of Medicine and Health Sciences, University of Antwerp, Antwerp, Belgium
| | - Guy Van Camp
- Center for Medical Genetics, University of Antwerp, Antwerp 2000, Belgium
| | - Peter Ponsaerts
- Laboratory of Experimental Hematology, Vaccine and Infectious Disease Institute (Vaxinfectio), University of Antwerp, Antwerp, Belgium
| | - Vincent Van Rompaey
- Department of Translational Neurosciences, Faculty of Medicine and Health Sciences, University of Antwerp, Antwerp, Belgium; Department of Otorhinolaryngology and Head & Neck Surgery, Antwerp University Hospital, Antwerp, Belgium
| | - Erik de Vrieze
- Department of Otorhinolaryngology, Hearing and Genes, Radboud University Medical Center, Nijmegen, GA 6525, the Netherlands.
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Moyaert J, Gilles A, Mertens G, Lammers MJW, Gommeren H, Janssens de Varebeke S, Fransen E, Verhaert N, Denys S, van de Berg R, Pennings R, Vanderveken O, Van Rompaey V. Interaural and sex differences in the natural evolution of hearing levels in pre-symptomatic and symptomatic carriers of the p.Pro51Ser variant in the COCH gene. Sci Rep 2024; 14:184. [PMID: 38167558 PMCID: PMC10762206 DOI: 10.1038/s41598-023-50583-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2023] [Accepted: 12/21/2023] [Indexed: 01/05/2024] Open
Abstract
Hearing impairment constitutes a significant health problem in developed countries. If hearing loss is slowly progressive, the first signs may not be noticed in time, or remain untreated until the moment the auditory dysfunction becomes more apparent. The present study will focus on DFNA9, an autosomal dominant disorder caused by pathogenic variants in the COCH gene. Although several cross-sectional studies on this topic have been conducted, a crucial need for longitudinal research has been reported by many authors. Longitudinal trajectories of individual hearing thresholds were established as function of age and superimposed lowess curves were generated for 101 female and male carriers of the p.Pro51Ser variant. The average number of times patients have been tested was 2.49 years with a minimum of 1 year and a maximum of 4 years. In addition, interaural and sex differences were studied, as they could modify the natural evolution of the hearing function. The current study demonstrates that, both in female carriers and male carriers, the first signs of hearing decline, i.e. hearing thresholds of 20 dB HL, become apparent as early as the 3rd decade in the highest frequencies. In addition, a rapid progression of SNHL occurs between 40 and 50 years of age. Differences between male and female carriers in the progression of hearing loss are most obvious between the age of 50 and 65 years. Furthermore, interaural discrepancies also manifest from the age of 50 years onwards. High-quality prospective data on the long-term natural evolution of hearing levels offer the opportunity to identify different disease stages in each cochlea and different types of evolution. This will provide more insights in the window of opportunity for future therapeutic intervention trials.
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Affiliation(s)
- Julie Moyaert
- Department of Translational Neurosciences, Faculty of Medicine and Health Sciences, University of Antwerp, Antwerp, Belgium.
- Department of Otorhinolaryngology and Head and Neck Surgery, Antwerp University Hospital, Edegem, Belgium.
| | - Annick Gilles
- Department of Translational Neurosciences, Faculty of Medicine and Health Sciences, University of Antwerp, Antwerp, Belgium
- Department of Otorhinolaryngology and Head and Neck Surgery, Antwerp University Hospital, Edegem, Belgium
| | - Griet Mertens
- Department of Translational Neurosciences, Faculty of Medicine and Health Sciences, University of Antwerp, Antwerp, Belgium
- Department of Otorhinolaryngology and Head and Neck Surgery, Antwerp University Hospital, Edegem, Belgium
| | - Marc J W Lammers
- Department of Translational Neurosciences, Faculty of Medicine and Health Sciences, University of Antwerp, Antwerp, Belgium
- Department of Otorhinolaryngology and Head and Neck Surgery, Antwerp University Hospital, Edegem, Belgium
| | - Hanne Gommeren
- Department of Translational Neurosciences, Faculty of Medicine and Health Sciences, University of Antwerp, Antwerp, Belgium
- Department of Otorhinolaryngology and Head and Neck Surgery, Antwerp University Hospital, Edegem, Belgium
| | | | - Erik Fransen
- Centre of Medical Genetics, University of Antwerp, Antwerp, Belgium
| | - Nicolas Verhaert
- Department of Neurosciences, Research Group Experimental Otorhinolaryngology (ExpORL), KU Leuven, Leuven, Belgium
- Department of Otorhinolaryngology and Head and Neck Surgery, University Hospitals of Leuven, Leuven, Belgium
| | - Sam Denys
- Department of Neurosciences, Research Group Experimental Otorhinolaryngology (ExpORL), KU Leuven, Leuven, Belgium
- Department of Otorhinolaryngology and Head and Neck Surgery, University Hospitals of Leuven, Leuven, Belgium
| | - Raymond van de Berg
- Division of Balance Disorders, Department of Otorhinolaryngology and Head and Neck Surgery, Faculty of Health Medicine and Life Sciences, Maastricht University Medical Center, Maastricht, The Netherlands
| | - Ronald Pennings
- Department of Otorhinolaryngology and Head and Neck Surgery, Radboud UMC, Nijmegen, The Netherlands
| | - Olivier Vanderveken
- Department of Translational Neurosciences, Faculty of Medicine and Health Sciences, University of Antwerp, Antwerp, Belgium
- Department of Otorhinolaryngology and Head and Neck Surgery, Antwerp University Hospital, Edegem, Belgium
| | - Vincent Van Rompaey
- Department of Translational Neurosciences, Faculty of Medicine and Health Sciences, University of Antwerp, Antwerp, Belgium
- Department of Otorhinolaryngology and Head and Neck Surgery, Antwerp University Hospital, Edegem, Belgium
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Peng Y, Xiang M, Fan T, Zhong X, Dai A, Feng J, Guan P, Gong J, Li J, Wang Y. A Novel COCH p.D544Vfs*3 Variant Associated with DFNA9 Sensorineural Hearing Loss Causes Pathological Multimeric Cochlin Formation. Life (Basel) 2023; 14:33. [PMID: 38255649 PMCID: PMC10817332 DOI: 10.3390/life14010033] [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: 11/08/2023] [Revised: 12/16/2023] [Accepted: 12/19/2023] [Indexed: 01/24/2024] Open
Abstract
COCH (coagulation factor C homology) is one of the most frequently mutated genes of autosomal dominant non-syndromic hearing loss. Variants in COCH could cause DFNA9, which is characterized by late-onset hearing loss with variable degrees of vestibular dysfunction. In this study, we report a Chinese family with a novel COCH variant (c.1687delA) causing p.D544Vfs*3 in the cochlin. Comprehensive audiometric tests and vestibular function assessments were taken to acquire the phenotypic profile of the subjects. Next-generation sequencing was conducted and segregation analysis was carried out using Sanger sequencing. The proband presented mild vestibular symptoms and normal functional assessment results in almost every test, while the variant co-segregated with hearing impairment in the pedigree. The variant was located beyond the vWFA2 domain, which was predicted to affect the post-translational cleavage of the cochlin via molecular modeling analysis. Notably, in the overexpressing study, by transient transfecting the HEK 293T cells, we found that the p.D544Vfs*3 variant increased the formation of multimeric cochlin. Our result enriched the spectrum of DFNA9-linked pathological COCH variants and suggested that variants, causative of cochlin multimerization, could be related to DFNA9 with sensorineural hearing loss rather than serious vestibular symptoms.
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Affiliation(s)
- Yingqiu Peng
- ENT Institute and Department of Otorhinolaryngology, EYE & ENT Hospital, Fudan University, Shanghai 200031, China
- NHC Key Laboratory of Hearing Medicine, Fudan University, Shanghai 200031, China
| | - Mengya Xiang
- ENT Institute and Department of Otorhinolaryngology, EYE & ENT Hospital, Fudan University, Shanghai 200031, China
- NHC Key Laboratory of Hearing Medicine, Fudan University, Shanghai 200031, China
| | - Ting Fan
- ENT Institute and Department of Otorhinolaryngology, EYE & ENT Hospital, Fudan University, Shanghai 200031, China
- NHC Key Laboratory of Hearing Medicine, Fudan University, Shanghai 200031, China
| | - Xiaofang Zhong
- Clinical Laboratory Center, Children’s Hospital of Fudan University, Shanghai 201102, China
| | - Aqiang Dai
- ENT Institute and Department of Otorhinolaryngology, EYE & ENT Hospital, Fudan University, Shanghai 200031, China
| | - Jialing Feng
- ENT Institute and Department of Otorhinolaryngology, EYE & ENT Hospital, Fudan University, Shanghai 200031, China
| | - Pengfei Guan
- ENT Institute and Department of Otorhinolaryngology, EYE & ENT Hospital, Fudan University, Shanghai 200031, China
- NHC Key Laboratory of Hearing Medicine, Fudan University, Shanghai 200031, China
| | - Jiamin Gong
- ENT Institute and Department of Otorhinolaryngology, EYE & ENT Hospital, Fudan University, Shanghai 200031, China
| | - Jian Li
- Clinical Laboratory Center, Children’s Hospital of Fudan University, Shanghai 201102, China
| | - Yunfeng Wang
- ENT Institute and Department of Otorhinolaryngology, EYE & ENT Hospital, Fudan University, Shanghai 200031, China
- NHC Key Laboratory of Hearing Medicine, Fudan University, Shanghai 200031, China
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Murakami K, Tamura R, Ikehara S, Ota H, Ichimiya T, Matsumoto N, Matsubara H, Nishihara S, Ikehara Y, Yamamoto K. Construction of mouse cochlin mutants with different GAG-binding specificities and their use for immunohistochemistry. Biochem J 2023; 480:41-56. [PMID: 36511224 PMCID: PMC9987951 DOI: 10.1042/bcj20220339] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2022] [Revised: 11/29/2022] [Accepted: 12/12/2022] [Indexed: 12/14/2022]
Abstract
Glycosaminoglycan (GAG) is a polysaccharide present on the cell surface as an extracellular matrix component, and is composed of repeating disaccharide units consisting of an amino sugar and uronic acid except in the case of the keratan sulfate. Sulfated GAGs, such as heparan sulfate, heparin, and chondroitin sulfate mediate signal transduction of growth factors, and their functions vary with the type and degree of sulfated modification. We have previously identified human and mouse cochlins as proteins that bind to sulfated GAGs. Here, we prepared a recombinant cochlin fused to human IgG-Fc or Protein A at the C-terminus as a detection and purification tag and investigated the ligand specificity of cochlin. We found that cochlin can be used as a specific probe for highly sulfated heparan sulfate and chondroitin sulfate E. We then used mutant analysis to identify the mechanism by which cochlin recognizes GAGs and developed a GAG detection system using cochlin. Interestingly, a mutant lacking the vWA2 domain bound to various types of GAGs. The N-terminal amino acid residues of cochlin contributed to its binding to heparin. Pathological specimens from human myocarditis patients were stained with a cochlin-Fc mutant. The results showed that both tryptase-positive and tryptase-negative mast cells were stained with this mutant. The identification of detailed modification patterns of GAGs is an important method to elucidate the molecular mechanisms of various diseases. The method developed for evaluating the expression of highly sulfated GAGs will help understand the biological and pathological importance of sulfated GAGs in the future.
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Affiliation(s)
- Karin Murakami
- Department of Integrated Biosciences, Graduate School of Frontier Sciences, The University of Tokyo, Kashiwa, Chiba, Japan
| | - Ryo Tamura
- Department of Integrated Biosciences, Graduate School of Frontier Sciences, The University of Tokyo, Kashiwa, Chiba, Japan
| | - Sanae Ikehara
- Graduate School of Medicine, Chiba University, Chiba, Chiba, Japan
| | - Hayato Ota
- Department of Bioinformatics, Graduate School of Engineering, Soka University, Hachioji, Tokyo, Japan
| | - Tomomi Ichimiya
- Department of Bioinformatics, Graduate School of Engineering, Soka University, Hachioji, Tokyo, Japan
| | - Naoki Matsumoto
- Department of Integrated Biosciences, Graduate School of Frontier Sciences, The University of Tokyo, Kashiwa, Chiba, Japan
| | | | - Shoko Nishihara
- Department of Bioinformatics, Graduate School of Engineering, Soka University, Hachioji, Tokyo, Japan
- Glycan and Life System Integration Center (GaLSIC), Soka University, Hachioji, Tokyo, Japan
| | - Yuzuru Ikehara
- Graduate School of Medicine, Chiba University, Chiba, Chiba, Japan
| | - Kazuo Yamamoto
- Department of Integrated Biosciences, Graduate School of Frontier Sciences, The University of Tokyo, Kashiwa, Chiba, Japan
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Radiologic Features in Cochlear Implant Candidates: A Prospective Study Comparing Candidates Carrying the p.Pro51Ser Mutation in Coagulation Factor C Homology With Noncarriers. Otol Neurotol 2022; 43:e969-e975. [PMID: 36001698 DOI: 10.1097/mao.0000000000003640] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
BACKGROUND DFNA9 is a form of autosomal progressive sensorineural hearing loss, caused by more than 30 variants in the COCH gene. p.Pro51Ser (p.P51S) variant is characterized by late-onset functional deterioration toward bilateral severe hearing loss and vestibulopathy. Focal sclerosis on computed tomography (CT) and T2-weighted magnetic resonance imaging (MRI) signal loss of semicircular canals are presumably radiologic biomarkers of advanced otovestibular deterioration. OBJECTIVES The aim of this study was to investigate whether these biomarkers are more frequent in cochlear implant candidates carrying the p.P51S mutation versus noncarriers. Second, the correlation between the hearing and vestibular function and carrier status was studied. Finally, the relationship between the presence of these radiologic features and the degree of hearing and vestibular deterioration was investigated. METHODS A prospective cohort study was performed on 38 candidates for cochlear implantation in a tertiary referral center. Patients underwent pure tone audiometry, videonystagmography, video head impulse tests and vestibular-evoked myogenic potentials. In addition, three dizziness questionnaires were used. All subjects were administered CT, MRI, and molecular genetic analysis. RESULTS Sixteen of 38 patients were carriers of the p.P51S COCH mutation. Radiologic lesions were almost exclusively observed in carriers. MRI was more sensitive in showing lesions than CT. Furthermore, p.P51S carriers showed significantly lower function on most vestibular tests, including questionnaires, than noncarriers. Patients with imaging abnormalities showed more pronounced vestibulopathy. CONCLUSION The present study supplements previous data that endorse the hypothesis that focal sclerosis of semicircular canals are biomarkers of advanced vestibular deterioration, especially in DFNA9.
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Honda T, Kawasaki N, Yanagihara R, Tamura R, Murakami K, Ichimiya T, Matsumoto N, Nishihara S, Yamamoto K. Involvement of cochlin binding to sulfated heparan sulfate/heparin in the pathophysiology of autosomal dominant late-onset hearing loss (DFNA9). PLoS One 2022; 17:e0268485. [PMID: 35901072 PMCID: PMC9333281 DOI: 10.1371/journal.pone.0268485] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2022] [Accepted: 05/01/2022] [Indexed: 11/30/2022] Open
Abstract
Late-onset non-syndromic autosomal dominant hearing loss 9 (DFNA9) is a hearing impairment caused by mutations in the coagulation factor C homology gene (COCH). COCH encodes for cochlin, a major component of the cochlear extracellular matrix. Though biochemical and genetic studies have characterized the properties of wild-type and mutated cochlins derived from DFNA9, little is known about the underlying pathogenic mechanism. In this study, we established a cochlin reporter cell, which allowed us to monitor the interaction of cochlin with its ligand(s) by means of a β-galactosidase assay. We found a class of highly sulfated glycosaminoglycans (GAGs), heparin, that were selectively bound to cochlin. The interaction was distinctly abrogated by N-desulfation, but not by 2-O- or 6-O-desulfation. The binding of cochlin to GAG was diminished by all of the point mutations found in DFNA9 patients. Through GAG composition analysis and immunostaining using mouse cochlin/immunoglobulin-Fc fusion protein, we identified moderately sulfated GAGs in mouse cochlea tissue; this implies that cochlin binds to such sulfated GAGs in the cochlea. Since GAGs play an important role in cell growth and survival as co-receptors of signal transduction mechanisms, the interaction of cochlin with GAGs in the extracellular matrix could aid the pathological research of autosomal dominant late-onset hearing loss in DFNA9.
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Affiliation(s)
- Tomoko Honda
- Department of Integrated Biosciences, Graduate School of Frontier Sciences, The University of Tokyo, Chiba, Japan
| | - Norihito Kawasaki
- Department of Integrated Biosciences, Graduate School of Frontier Sciences, The University of Tokyo, Chiba, Japan
| | - Rei Yanagihara
- Department of Integrated Biosciences, Graduate School of Frontier Sciences, The University of Tokyo, Chiba, Japan
| | - Ryo Tamura
- Department of Integrated Biosciences, Graduate School of Frontier Sciences, The University of Tokyo, Chiba, Japan
| | - Karin Murakami
- Department of Integrated Biosciences, Graduate School of Frontier Sciences, The University of Tokyo, Chiba, Japan
| | - Tomomi Ichimiya
- Department of Bioinformatics, Graduate School of Engineering, Soka University, Hachioji, Tokyo, Japan
| | - Naoki Matsumoto
- Department of Integrated Biosciences, Graduate School of Frontier Sciences, The University of Tokyo, Chiba, Japan
| | - Shoko Nishihara
- Department of Bioinformatics, Graduate School of Engineering, Soka University, Hachioji, Tokyo, Japan
- Glycan & Life System Integration Center (GaLSIC), Soka University, Hachioji, Tokyo, Japan
| | - Kazuo Yamamoto
- Department of Integrated Biosciences, Graduate School of Frontier Sciences, The University of Tokyo, Chiba, Japan
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Oh KS, Walls D, Joo SY, Kim JA, Yoo JE, Koh YI, Kim DH, Rim JH, Choi HJ, Kim HY, Yu S, Smith RJ, Choi JY, Gee HY, Jung J. COCH-related autosomal dominant nonsyndromic hearing loss: a phenotype-genotype study. Hum Genet 2022; 141:889-901. [PMID: 34529116 PMCID: PMC8924011 DOI: 10.1007/s00439-021-02368-y] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2021] [Accepted: 09/08/2021] [Indexed: 12/20/2022]
Abstract
This phenotype-genotype study aimed to investigate the extent of audioprofile variability related to cochlin major domains and to identify potential ethnic-specific differences associated with COCH-related hearing loss. Eight Korean families (26 cases) were diagnosed with COCH-related hearing loss by exome sequencing. Audiometric test results were combined with those from nine published East Asian families (20 cases) and compared with those from 38 European-descent families (277 cases). Audioprofiles were created by grouping audiometric test results into age ranges by age at testing and then averaging hearing loss thresholds by frequency within age ranges. The functional impact of the identified variants was assessed in vitro by examining the intracellular trafficking, secretion, and cleavage of cochlin. In both East Asian and European-descent families segregating COCH-related hearing loss, deafness-associated variants in non-LCCL domains of cochlin were associated with hearing loss that was more severe earlier in life than hearing loss caused by variants in the LCCL domain. Consistent with this phenotypic difference, functional studies demonstrated distinct pathogenic mechanisms for COCH variants in a domain-dependent manner; specifically, a cytotoxic effect was observed for the p.Phe230Leu variant, which is located in the vWFA1 domain. No ethnic-specific differences in hearing loss progression were observed, except for those attributable to an overrepresentation of presymptomatic cases in the European-descent cohort.
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Affiliation(s)
- Kyung Seok Oh
- Department of Pharmacology, Graduate School of Medical Science, Brain Korea 21 Project, Yonsei University College of Medicine, 50-1 Yonsei-ro, Seodaemun-gu, Seoul, 03722, Republic of Korea
| | - Daniel Walls
- Molecular Otolaryngology and Renal Research Laboratories, Department of Otolaryngology‑Head and Neck Surgery, University of Iowa Carver College of Medicine, Iowa City, IA, 52242, USA
| | - Sun Young Joo
- Department of Pharmacology, Graduate School of Medical Science, Brain Korea 21 Project, Yonsei University College of Medicine, 50-1 Yonsei-ro, Seodaemun-gu, Seoul, 03722, Republic of Korea
| | - Jung Ah Kim
- Department of Pharmacology, Graduate School of Medical Science, Brain Korea 21 Project, Yonsei University College of Medicine, 50-1 Yonsei-ro, Seodaemun-gu, Seoul, 03722, Republic of Korea
| | - Jee Eun Yoo
- Department of Otorhinolaryngology, Graduate School of Medical Science, Brain Korea 21 Project, Yonsei University College of Medicine, 50-1 Yonsei-ro, Seodaemun-gu, Seoul, 03722, Republic of Korea
| | - Young Ik Koh
- Department of Pharmacology, Graduate School of Medical Science, Brain Korea 21 Project, Yonsei University College of Medicine, 50-1 Yonsei-ro, Seodaemun-gu, Seoul, 03722, Republic of Korea
| | - Da Hye Kim
- Department of Otorhinolaryngology, Graduate School of Medical Science, Brain Korea 21 Project, Yonsei University College of Medicine, 50-1 Yonsei-ro, Seodaemun-gu, Seoul, 03722, Republic of Korea
| | - John Hoon Rim
- Department of Pharmacology, Graduate School of Medical Science, Brain Korea 21 Project, Yonsei University College of Medicine, 50-1 Yonsei-ro, Seodaemun-gu, Seoul, 03722, Republic of Korea
| | - Hye Ji Choi
- Department of Otorhinolaryngology, Graduate School of Medical Science, Brain Korea 21 Project, Yonsei University College of Medicine, 50-1 Yonsei-ro, Seodaemun-gu, Seoul, 03722, Republic of Korea
| | - Hye-Youn Kim
- Department of Pharmacology, Graduate School of Medical Science, Brain Korea 21 Project, Yonsei University College of Medicine, 50-1 Yonsei-ro, Seodaemun-gu, Seoul, 03722, Republic of Korea
| | - Seyoung Yu
- Department of Pharmacology, Graduate School of Medical Science, Brain Korea 21 Project, Yonsei University College of Medicine, 50-1 Yonsei-ro, Seodaemun-gu, Seoul, 03722, Republic of Korea
| | - Richard J Smith
- Molecular Otolaryngology and Renal Research Laboratories, Department of Otolaryngology‑Head and Neck Surgery, University of Iowa Carver College of Medicine, Iowa City, IA, 52242, USA.
- Interdepartmental Ph.D. Program in Genetics, University of Iowa, Iowa City, IA, 52242, USA.
- Department of Molecular Physiology and Biophysics, University of Iowa Carver College of Medicine, Iowa City, IA, 52242, USA.
| | - Jae Young Choi
- Department of Otorhinolaryngology, Graduate School of Medical Science, Brain Korea 21 Project, Yonsei University College of Medicine, 50-1 Yonsei-ro, Seodaemun-gu, Seoul, 03722, Republic of Korea.
| | - Heon Yung Gee
- Department of Pharmacology, Graduate School of Medical Science, Brain Korea 21 Project, Yonsei University College of Medicine, 50-1 Yonsei-ro, Seodaemun-gu, Seoul, 03722, Republic of Korea.
| | - Jinsei Jung
- Department of Pharmacology, Graduate School of Medical Science, Brain Korea 21 Project, Yonsei University College of Medicine, 50-1 Yonsei-ro, Seodaemun-gu, Seoul, 03722, Republic of Korea.
- Department of Otorhinolaryngology, Graduate School of Medical Science, Brain Korea 21 Project, Yonsei University College of Medicine, 50-1 Yonsei-ro, Seodaemun-gu, Seoul, 03722, Republic of Korea.
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Salah M, Moyaert J, Vanderveken O, Schepers S, Termote B, Van Rompaey V, Janssens de Varebeke S. Does Vestibulo-Ocular Reflex (VOR) Gain Correlate With Radiological Findings in the Semi-Circular Canals in Patients Carrying the p.Pro51Ser (P51S) COCH Variant Causing DFNA9? Relationship Between the Three-Dimensional Video Head Impulse Test (vHIT) and MR/CT Imaging. Otol Neurotol 2022; 43:e348-e354. [PMID: 35020687 DOI: 10.1097/mao.0000000000003434] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
OBJECTIVE The primary aim was to determine whether 3D video-head-impulse-test vestibulo-ocular reflex (vHIT VOR)-gains correlate with computed tomography (CT) and magnetic resonance (MR) lesions in a series of carriers of the p.(Pro51Ser)-variant (P51S) in the COCH-gene (DFNA9). Secondary aim was to compare routine imaging with second peer review radiologic lecture. STUDY DESIGN Analytical cross-sectional study. SETTING Secondary referral center. PATIENTS Twenty-four p.P51S carriers with MR and CT images. Eighteen carriers were selected of whom both 3D-vHIT and imaging data were available within a time interval of 24 months. INTERVENTIONS All imaging data were reassessed by two independent neuroradiologists. vHIT VOR-gains were correlated with semi-circular canal (SCC) lesions. MAIN OUTCOME MEASURES Correlation between vHIT VOR-gains and SCC lesions, and additional lesions detected during scientific lecture of imaging data. RESULTS The average gain of the ipsilateral labyrinth was significantly lower when positive CT (0.3215; p = 0.0122) and MR results (0.3215; p = 0.0134).92% of ears presented MR lesions on at least one SCC, whereas this was 75% on CT. The posterior SCC is the most frequently affected on MR and CT. Second lecture led to nine additional MR and 16 CT lesions. CONCLUSIONS Significant correlation was observed between radiological lesions at any SCC and lower average gain of the three ipsilateral SCC. The substantially larger number of lesions during scientific assessment stresses the need to fully inform radiologists concerning differential diagnosis to facilitate accurate diagnosis when planning imaging. Focal sclerosis and narrowing of SCC in DFNA9 represent a possible biomarker of advanced stages of otovestibular deterioration.
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Affiliation(s)
- Mahadi Salah
- Department of Otorhinolaryngology & Head and Neck Surgery, Jessa Hospital, Hasselt
- Faculty of Medicine and Health Sciences, University of Antwerp
- Department of Otorhinolaryngology & Head and Neck Surgery, Antwerp University Hospital, Antwerp
| | - Julie Moyaert
- Department of Otorhinolaryngology & Head and Neck Surgery, Antwerp University Hospital, Antwerp
| | - Olivier Vanderveken
- Faculty of Medicine and Health Sciences, University of Antwerp
- Department of Otorhinolaryngology & Head and Neck Surgery, Antwerp University Hospital, Antwerp
| | | | - Bruno Termote
- Department of Radiology, Jessa Hospital, Hasselt, Belgium
| | - Vincent Van Rompaey
- Faculty of Medicine and Health Sciences, University of Antwerp
- Department of Otorhinolaryngology & Head and Neck Surgery, Antwerp University Hospital, Antwerp
| | - Sebastien Janssens de Varebeke
- Department of Otorhinolaryngology & Head and Neck Surgery, Jessa Hospital, Hasselt
- Faculty of Medicine and Health Sciences, University of Antwerp
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9
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Robijn SMM, Smits JJ, Sezer K, Huygen PLM, Beynon AJ, van Wijk E, Kremer H, de Vrieze E, Lanting CP, Pennings RJE. Genotype-Phenotype Correlations of Pathogenic COCH Variants in DFNA9: A HuGE Systematic Review and Audiometric Meta-Analysis. Biomolecules 2022; 12:220. [PMID: 35204720 PMCID: PMC8961530 DOI: 10.3390/biom12020220] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2021] [Revised: 01/21/2022] [Accepted: 01/23/2022] [Indexed: 02/04/2023] Open
Abstract
Pathogenic missense variants in COCH are associated with DFNA9, an autosomal dominantly inherited type of progressive sensorineural hearing loss with or without vestibular dysfunction. This study is a comprehensive overview of genotype-phenotype correlations using the PRISMA and HuGENet guidelines. Study characteristics, risk of bias, genotyping and data on the self-reported age of onset, symptoms of vestibular dysfunction, normative test results for vestibular function, and results of audiovestibular examinations were extracted for each underlying pathogenic COCH variant. The literature search yielded 48 studies describing the audiovestibular phenotypes of 27 DFNA9-associated variants in COCH. Subsequently, meta-analysis of audiometric data was performed by constructing age-related typical audiograms and by performing non-linear regression analyses on the age of onset and progression of hearing loss. Significant differences were found between the calculated ages of onset and progression of the audiovestibular phenotypes of subjects with pathogenic variants affecting either the LCCL domain of cochlin or the vWFA2 and Ivd1 domains. We conclude that the audiovestibular phenotypes associated with DFNA9 are highly variable. Variants affecting the LCCL domain of cochlin generally lead to more progression of hearing loss when compared to variants affecting the other domains. This review serves as a reference for prospective natural history studies in anticipation of mutation-specific therapeutic interventions.
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Affiliation(s)
- Sybren M. M. Robijn
- Department of Otorhinolaryngology, Hearing & Genes, Radboud University Medical Center, 6525 GA Nijmegen, The Netherlands; (S.M.M.R.); (J.J.S.); (K.S.); (P.L.M.H.); (A.J.B.); (E.v.W.); (E.d.V.); (C.P.L.)
- Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center, 6500 GL Nijmegen, The Netherlands;
| | - Jeroen J. Smits
- Department of Otorhinolaryngology, Hearing & Genes, Radboud University Medical Center, 6525 GA Nijmegen, The Netherlands; (S.M.M.R.); (J.J.S.); (K.S.); (P.L.M.H.); (A.J.B.); (E.v.W.); (E.d.V.); (C.P.L.)
- Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center, 6500 GL Nijmegen, The Netherlands;
- Department of Human Genetics, Radboud University Medical Center, 6525 GA Nijmegen, The Netherlands
| | - Kadriye Sezer
- Department of Otorhinolaryngology, Hearing & Genes, Radboud University Medical Center, 6525 GA Nijmegen, The Netherlands; (S.M.M.R.); (J.J.S.); (K.S.); (P.L.M.H.); (A.J.B.); (E.v.W.); (E.d.V.); (C.P.L.)
| | - Patrick L. M. Huygen
- Department of Otorhinolaryngology, Hearing & Genes, Radboud University Medical Center, 6525 GA Nijmegen, The Netherlands; (S.M.M.R.); (J.J.S.); (K.S.); (P.L.M.H.); (A.J.B.); (E.v.W.); (E.d.V.); (C.P.L.)
| | - Andy J. Beynon
- Department of Otorhinolaryngology, Hearing & Genes, Radboud University Medical Center, 6525 GA Nijmegen, The Netherlands; (S.M.M.R.); (J.J.S.); (K.S.); (P.L.M.H.); (A.J.B.); (E.v.W.); (E.d.V.); (C.P.L.)
| | - Erwin van Wijk
- Department of Otorhinolaryngology, Hearing & Genes, Radboud University Medical Center, 6525 GA Nijmegen, The Netherlands; (S.M.M.R.); (J.J.S.); (K.S.); (P.L.M.H.); (A.J.B.); (E.v.W.); (E.d.V.); (C.P.L.)
- Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center, 6500 GL Nijmegen, The Netherlands;
| | - Hannie Kremer
- Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center, 6500 GL Nijmegen, The Netherlands;
- Department of Human Genetics, Radboud University Medical Center, 6525 GA Nijmegen, The Netherlands
| | - Erik de Vrieze
- Department of Otorhinolaryngology, Hearing & Genes, Radboud University Medical Center, 6525 GA Nijmegen, The Netherlands; (S.M.M.R.); (J.J.S.); (K.S.); (P.L.M.H.); (A.J.B.); (E.v.W.); (E.d.V.); (C.P.L.)
- Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center, 6500 GL Nijmegen, The Netherlands;
| | - Cornelis P. Lanting
- Department of Otorhinolaryngology, Hearing & Genes, Radboud University Medical Center, 6525 GA Nijmegen, The Netherlands; (S.M.M.R.); (J.J.S.); (K.S.); (P.L.M.H.); (A.J.B.); (E.v.W.); (E.d.V.); (C.P.L.)
- Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center, 6500 GL Nijmegen, The Netherlands;
| | - Ronald J. E. Pennings
- Department of Otorhinolaryngology, Hearing & Genes, Radboud University Medical Center, 6525 GA Nijmegen, The Netherlands; (S.M.M.R.); (J.J.S.); (K.S.); (P.L.M.H.); (A.J.B.); (E.v.W.); (E.d.V.); (C.P.L.)
- Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center, 6500 GL Nijmegen, The Netherlands;
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10
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Seist R, Landegger LD, Robertson NG, Vasilijic S, Morton CC, Stankovic KM. Cochlin Deficiency Protects Against Noise-Induced Hearing Loss. Front Mol Neurosci 2021; 14:670013. [PMID: 34108864 PMCID: PMC8180578 DOI: 10.3389/fnmol.2021.670013] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2021] [Accepted: 04/16/2021] [Indexed: 12/20/2022] Open
Abstract
Cochlin is the most abundant protein in the inner ear. To study its function in response to noise trauma, we exposed adolescent wild-type (Coch +/+ ) and cochlin knock-out (Coch -/-) mice to noise (8-16 kHz, 103 dB SPL, 2 h) that causes a permanent threshold shift and hair cell loss. Two weeks after noise exposure, Coch-/- mice had substantially less elevation in noise-induced auditory thresholds and hair cell loss than Coch + / + mice, consistent with cochlin deficiency providing protection from noise trauma. Comparison of pre-noise exposure thresholds of auditory brain stem responses (ABRs) and distortion product otoacoustic emissions (DPOAEs) in Coch-/- mice and Coch + / + littermates revealed a small and significant elevation in thresholds of Coch-/- mice, overall consistent with a small conductive hearing loss in Coch-/- mice. We show quantitatively that the pro-inflammatory component of cochlin, LCCL, is upregulated after noise exposure in perilymph of wild-type mice compared to unexposed mice, as is the enzyme catalyzing LCCL release, aggrecanase1, encoded by Adamts4. We further show that upregulation of pro-inflammatory cytokines in perilymph and cochlear soft-tissue after noise exposure is lower in cochlin knock-out than wild-type mice. Taken together, our data demonstrate for the first time that cochlin deficiency results in conductive hearing loss that protects against physiologic and molecular effects of noise trauma.
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Affiliation(s)
- Richard Seist
- Eaton-Peabody Laboratories and Department of Otolaryngology – Head and Neck Surgery, Massachusetts Eye and Ear, Boston, MA, United States
- Department of Otolaryngology – Head and Neck Surgery, Harvard Medical School, Boston, MA, United States
- Department of Otorhinolaryngology – Head and Neck Surgery, Paracelsus Medical University, Salzburg, Austria
| | - Lukas D. Landegger
- Eaton-Peabody Laboratories and Department of Otolaryngology – Head and Neck Surgery, Massachusetts Eye and Ear, Boston, MA, United States
- Department of Otolaryngology – Head and Neck Surgery, Harvard Medical School, Boston, MA, United States
- Department of Otorhinolaryngology – Head and Neck Surgery, Medical University of Vienna, Vienna, Austria
| | - Nahid G. Robertson
- Department of Obstetrics and Gynecology and of Pathology, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA, United States
| | - Sasa Vasilijic
- Eaton-Peabody Laboratories and Department of Otolaryngology – Head and Neck Surgery, Massachusetts Eye and Ear, Boston, MA, United States
- Department of Otolaryngology – Head and Neck Surgery, Harvard Medical School, Boston, MA, United States
| | - Cynthia C. Morton
- Department of Obstetrics and Gynecology and of Pathology, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA, United States
- Broad Institute of MIT and Harvard, Cambridge, MA, United States
- Manchester Centre for Audiology and Deafness, School of Health Sciences, University of Manchester, Manchester, United Kingdom
- Program in Speech and Hearing Bioscience and Technology, Harvard Medical School, Boston, MA, United States
| | - Konstantina M. Stankovic
- Eaton-Peabody Laboratories and Department of Otolaryngology – Head and Neck Surgery, Massachusetts Eye and Ear, Boston, MA, United States
- Department of Otolaryngology – Head and Neck Surgery, Harvard Medical School, Boston, MA, United States
- Program in Speech and Hearing Bioscience and Technology, Harvard Medical School, Boston, MA, United States
- Harvard Program in Therapeutic Science, Harvard Medical School, Boston, MA, United States
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11
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de Vrieze E, Cañas Martín J, Peijnenborg J, Martens A, Oostrik J, van den Heuvel S, Neveling K, Pennings R, Kremer H, van Wijk E. AON-based degradation of c.151C>T mutant COCH transcripts associated with dominantly inherited hearing impairment DFNA9. MOLECULAR THERAPY-NUCLEIC ACIDS 2021; 24:274-283. [PMID: 33815940 PMCID: PMC7985667 DOI: 10.1016/j.omtn.2021.02.033] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/12/2020] [Accepted: 02/24/2021] [Indexed: 01/22/2023]
Abstract
The c.151C>T founder mutation in COCH is a frequent cause of late-onset, dominantly inherited hearing impairment and vestibular dysfunction (DFNA9) in the Dutch/Belgian population. The initial clinical symptoms only manifest between the 3rd and 5th decade of life, which leaves ample time for therapeutic intervention. The dominant inheritance pattern and established non-haploinsufficiency disease mechanism indicate that suppressing translation of mutant COCH transcripts has high therapeutic potential. Single-molecule real-time (SMRT) sequencing resulted in the identification of 11 variants with a low population frequency (<10%) that are specific to the c.151C>T mutant COCH allele. Proof of concept was obtained that gapmer antisense oligonucleotides (AONs), directed against the c.151C>T mutation or mutant allele-specific intronic variants, are able to induce mutant COCH transcript degradation when delivered to transgenic cells expressing COCH minigenes. The most potent AON, directed against the c.151C>T mutation, was able to induce a 60% decrease in mutant COCH transcripts without affecting wild-type COCH transcript levels. Allele specificity decreased when increasing concentrations of AON were delivered to the cells. With the proven safety of AONs in humans, and rapid advancements in inner ear drug delivery, our in vitro studies indicate that AONs offer a promising treatment modality for DFNA9.
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Affiliation(s)
- Erik de Vrieze
- Department of Otorhinolaryngology, Radboud University Medical Center, 6525 GA Nijmegen, the Netherlands
- Donders Institute for Brain, Cognition, and Behaviour, Radboud University Medical Center, 6525 GA Nijmegen, the Netherlands
- Corresponding author: Erik de Vrieze, Department of Otorhinolaryngology, Radboud University Medical Center, P.O. Box 9101, 6525 GA Nijmegen (Route 855), the Netherlands.
| | - Jorge Cañas Martín
- Department of Otorhinolaryngology, Radboud University Medical Center, 6525 GA Nijmegen, the Netherlands
| | - Jolien Peijnenborg
- Department of Otorhinolaryngology, Radboud University Medical Center, 6525 GA Nijmegen, the Netherlands
| | - Aniek Martens
- Department of Otorhinolaryngology, Radboud University Medical Center, 6525 GA Nijmegen, the Netherlands
| | - Jaap Oostrik
- Department of Otorhinolaryngology, Radboud University Medical Center, 6525 GA Nijmegen, the Netherlands
- Donders Institute for Brain, Cognition, and Behaviour, Radboud University Medical Center, 6525 GA Nijmegen, the Netherlands
| | - Simone van den Heuvel
- Department of Human Genetics, Radboud University Medical Center, 6525 GA Nijmegen, the Netherlands
| | - Kornelia Neveling
- Department of Human Genetics, Radboud University Medical Center, 6525 GA Nijmegen, the Netherlands
- Radboud Institute for Health Sciences, Radboud University Medical Center, 6525 GA Nijmegen, the Netherlands
| | - Ronald Pennings
- Department of Otorhinolaryngology, Radboud University Medical Center, 6525 GA Nijmegen, the Netherlands
- Donders Institute for Brain, Cognition, and Behaviour, Radboud University Medical Center, 6525 GA Nijmegen, the Netherlands
| | - Hannie Kremer
- Department of Otorhinolaryngology, Radboud University Medical Center, 6525 GA Nijmegen, the Netherlands
- Donders Institute for Brain, Cognition, and Behaviour, Radboud University Medical Center, 6525 GA Nijmegen, the Netherlands
- Department of Human Genetics, Radboud University Medical Center, 6525 GA Nijmegen, the Netherlands
| | - Erwin van Wijk
- Department of Otorhinolaryngology, Radboud University Medical Center, 6525 GA Nijmegen, the Netherlands
- Donders Institute for Brain, Cognition, and Behaviour, Radboud University Medical Center, 6525 GA Nijmegen, the Netherlands
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12
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Verdoodt D, Van Camp G, Ponsaerts P, Van Rompaey V. On the pathophysiology of DFNA9: Effect of pathogenic variants in the COCH gene on inner ear functioning in human and transgenic mice. Hear Res 2020; 401:108162. [PMID: 33421658 DOI: 10.1016/j.heares.2020.108162] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/25/2020] [Revised: 11/27/2020] [Accepted: 12/27/2020] [Indexed: 12/20/2022]
Abstract
DeaFNess Autosomal Dominant 9 (DFNA9) is a dominant hereditary non-syndromic form of progressive sensorineural hearing loss often associated with vestibular dysfunction. DFNA9 is caused by pathogenic variants in the COCH gene. This gene encodes for cochlin, a protein that is abundantly expressed in the spiral ligament and spiral limbus of the inner ear but the function of cochlin is still not fully understood. There are 22 known pathogenic variants located in different domains of the COCH gene that can cause DFNA9, all expressing slightly different phenotypes. It is believed that COCH mutations affect the intracellular trafficking of cochlin which could explain the characteristic pathology seen in temporal bones of DFNA9 patients. This pathology involves a widespread accumulation of acellular eosinophilic deposits throughout the labyrinth. To gain a better understanding of the pathology underlying DFNA9, different mouse models were developed. The objective of this review is to describe the different pathogenic variants in the COCH gene and their effect on intracellular trafficking, associated phenotypes and histopathological findings in both patients and mouse models.
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Affiliation(s)
- Dorien Verdoodt
- Department of Translational Neurosciences, Faculty of Medicine and Health Sciences, University of Antwerp, Belgium; Laboratory of Experimental Hematology, Faculty of Medicine and Health Sciences, Vaccine and Infectious Disease Institute (Vaxinfectio), University of Antwerp, Belgium.
| | - Guy Van Camp
- Centre of Medical Genetics, Faculty of Medicine and Health Sciences, University of Antwerp, Belgium
| | - Peter Ponsaerts
- Laboratory of Experimental Hematology, Faculty of Medicine and Health Sciences, Vaccine and Infectious Disease Institute (Vaxinfectio), University of Antwerp, Belgium
| | - Vincent Van Rompaey
- Department of Translational Neurosciences, Faculty of Medicine and Health Sciences, University of Antwerp, Belgium; Department of Otorhinolaryngology and Head & Neck surgery, Antwerp University Hospital, Belgium
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13
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Abstract
OBJECTIVE In this review the authors discuss evidence from the literature concerning vitamin D and temporal bone diseases (benign paroxysmal positional vertigo [BPPV], Menière's disease [MD], vestibular neuritis, idiopathic facial paralysis, idiopathic acute hearing loss). Common features shared by Menière's disease, glaucoma, and the possible influence by vitamin D are briefly discussed. DATA SOURCES, STUDY SELECTION Publications from 1970 until recent times have been reviewed according to a keyword search (see above) in PubMed. CONCLUSIONS MD, BPPV, vestibular neuritis, idiopathic facial paralysis, idiopathic acute hearing loss may all have several etiological factors, but a common feature of the current theories is that an initial viral infection and a subsequent autoimmune/autoinflammatory reaction might be involved. Additionally, in some of these entities varying degrees of demyelination have been documented. Given the immunomodulatory effect of vitamin D, we postulate that it may play a role in suppressing an eventual postviral autoimmune reaction. This beneficial effect may be enhanced by the antioxidative activity of vitamin D and its potential in stabilizing endothelial cells. The association of vitamin D deficiency with demyelination has already been established in other entities such as multiple sclerosis and experimental autoimmune encephalitis. Mice without vitamin D receptor show degenerative features in inner ear ganglia, hair cells, as well as otoconia. The authors suggest further studies concerning the role of vitamin D deficiency in diseases of the temporal bone. Additionally, the possible presence and degree of demyelination in these entities will have to be elucidated more systematically in the future.
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14
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Lu X, Wang Q, Gu H, Zhang X, Qi Y, Liu Y. Whole exome sequencing identified a second pathogenic variant in HOMER2 for autosomal dominant non-syndromic deafness. Clin Genet 2019; 94:419-428. [PMID: 30047143 DOI: 10.1111/cge.13422] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2018] [Revised: 06/26/2018] [Accepted: 07/19/2018] [Indexed: 12/11/2022]
Abstract
Hearing loss is one of the most common sensory disorders worldwide, and about half of all occurrences are attributable to genetic factors. Here, we have identified a novel pathogenic variant in HOMER2 in a Chinese family with autosomal dominant, non-syndromic hearing loss. This is the second family reported globally with hearing loss caused by a variant in HOMER2. The pathogenic variant c.840_841insC in HOMER2 (NM_199330), segregating with the hearing-loss phenotype in the family, leads to a premature stop codon producing a truncated protein. The coiled-coil domain in the C-terminal of HOMER2 protein is essential for protein multimerization and HOMER2-CDC42 interaction. We compared the phenotypes in the two families and found that hearing impairment in this Chinese family was more severe. Furthermore, we found that the ability of this insertion mutant type HOMER2 (HOMER2MU ) to multimerize decreased more significantly than wild-type HOMER2 (HOMER2WT ) and the reported c.554G>C (NM_004839) mutant HOMER2. HOMER2MU protein tended to be distributed in a diffuse manner, whereas HOMER2WT and the reported mutant HOMER2 tended to cluster together. Our research provides a validating second family for variants in HOMER2 causing non-syndromic sensorineural hearing loss. HOMER2 homo-/hetero-multimerization might be the first step in exerting its normal function.
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Affiliation(s)
- X Lu
- Department of Otolaryngology, Head and Neck Surgery, Peking University First Hospital, Beijing, China
| | - Q Wang
- Department of Otolaryngology, Head and Neck Surgery, The Third Affiliated Hospital, Sun Yat-sen University, Guangzhou, China
| | - H Gu
- Department of Otolaryngology, Head and Neck Surgery, Peking University First Hospital, Beijing, China
| | - X Zhang
- Department of Otolaryngology, Head and Neck Surgery, Peking University First Hospital, Beijing, China
| | - Y Qi
- Department of Central Laboratory, Peking University First Hospital, Beijing, China
| | - Y Liu
- Department of Otolaryngology, Head and Neck Surgery, Peking University First Hospital, Beijing, China
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15
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Oza AM, DiStefano MT, Hemphill SE, Cushman BJ, Grant AR, Siegert RK, Shen J, Chapin A, Boczek NJ, Schimmenti LA, Murry JB, Hasadsri L, Nara K, Kenna M, Booth KT, Azaiez H, Griffith A, Avraham KB, Kremer H, Rehm HL, Amr SS, Abou Tayoun AN. Expert specification of the ACMG/AMP variant interpretation guidelines for genetic hearing loss. Hum Mutat 2019; 39:1593-1613. [PMID: 30311386 DOI: 10.1002/humu.23630] [Citation(s) in RCA: 295] [Impact Index Per Article: 59.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2018] [Revised: 07/23/2018] [Accepted: 08/25/2018] [Indexed: 12/23/2022]
Abstract
Due to the high genetic heterogeneity of hearing loss (HL), current clinical testing includes sequencing large numbers of genes, which often yields a significant number of novel variants. Therefore, the standardization of variant interpretation is crucial to provide consistent and accurate diagnoses. The Hearing Loss Variant Curation Expert Panel was created within the Clinical Genome Resource to provide expert guidance for standardized genomic interpretation in the context of HL. As one of its major tasks, our Expert Panel has adapted the American College of Medical Genetics and Genomics/Association for Molecular Pathology (ACMG/AMP) guidelines for the interpretation of sequence variants in HL genes. Here, we provide a comprehensive illustration of the newly specified ACMG/AMP HL rules. Three rules remained unchanged, four rules were removed, and the remaining 21 rules were specified. These rules were further validated and refined using a pilot set of 51 variants assessed by curators and disease experts. Of the 51 variants evaluated in the pilot, 37% (19/51) changed category based upon application of the expert panel specified rules and/or aggregation of evidence across laboratories. These HL-specific ACMG/AMP rules will help standardize variant interpretation, ultimately leading to better care for individuals with HL.
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Affiliation(s)
- Andrea M Oza
- Laboratory for Molecular Medicine, Partners Healthcare Personalized Medicine, Cambridge, Massachusetts.,Department of Otolaryngology and Communication Enhancement, Boston Children's Hospital, Boston, Massachusetts
| | - Marina T DiStefano
- Laboratory for Molecular Medicine, Partners Healthcare Personalized Medicine, Cambridge, Massachusetts.,Harvard Medical School, Boston, Massachusetts
| | - Sarah E Hemphill
- Laboratory for Molecular Medicine, Partners Healthcare Personalized Medicine, Cambridge, Massachusetts
| | - Brandon J Cushman
- Laboratory for Molecular Medicine, Partners Healthcare Personalized Medicine, Cambridge, Massachusetts
| | - Andrew R Grant
- Laboratory for Molecular Medicine, Partners Healthcare Personalized Medicine, Cambridge, Massachusetts
| | - Rebecca K Siegert
- Laboratory for Molecular Medicine, Partners Healthcare Personalized Medicine, Cambridge, Massachusetts
| | - Jun Shen
- Laboratory for Molecular Medicine, Partners Healthcare Personalized Medicine, Cambridge, Massachusetts.,Harvard Medical School, Boston, Massachusetts.,Department of Pathology, Brigham & Women's Hospital, Boston, Massachusetts
| | | | - Nicole J Boczek
- Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, Minnesota
| | - Lisa A Schimmenti
- Department of Otorhinolaryngology, Clinical Genomics and Biochemistry and Molecular Biology, Mayo Clinic, Rochester, Minnesota
| | - Jaclyn B Murry
- Laboratory for Molecular Medicine, Partners Healthcare Personalized Medicine, Cambridge, Massachusetts
| | - Linda Hasadsri
- Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, Minnesota
| | - Kiyomitsu Nara
- Division of Hearing and Balance Research, National Institute of Sensory Organs, National Hospital Organization Tokyo Medical Center, Tokyo, Japan
| | - Margaret Kenna
- Department of Otolaryngology and Communication Enhancement, Boston Children's Hospital, Boston, Massachusetts.,Harvard Medical School, Boston, Massachusetts
| | - Kevin T Booth
- Molecular Otolaryngology and Renal Research Laboratories, Department of Otolaryngology, University of Iowa Hospital and Clinics, Iowa City, Iowa.,The Interdisciplinary Graduate Program in Molecular Medicine, Carver College of Medicine, University of Iowa, Iowa City, Iowa
| | - Hela Azaiez
- Molecular Otolaryngology and Renal Research Laboratories, Department of Otolaryngology, University of Iowa Hospital and Clinics, Iowa City, Iowa
| | - Andrew Griffith
- Audiology Unit, National Institute on Deafness and Other Communication Disorders (NIDCD), NIH, Bethesda, Maryland
| | - Karen B Avraham
- Department of Human Molecular Genetics and Biochemistry, Sackler Faculty of Medicine and Sagol School of Neuroscience, Tel Aviv University, Tel Aviv, Israel
| | - Hannie Kremer
- Department of Otorhinolaryngology and Department of Human Genetics, Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Heidi L Rehm
- Laboratory for Molecular Medicine, Partners Healthcare Personalized Medicine, Cambridge, Massachusetts.,Harvard Medical School, Boston, Massachusetts.,Center for Genomic Medicine, Massachusetts General Hospital, Boston, Massachusetts.,The Broad Institute of MIT and Harvard, Cambridge, Massachusetts
| | - Sami S Amr
- Laboratory for Molecular Medicine, Partners Healthcare Personalized Medicine, Cambridge, Massachusetts.,Harvard Medical School, Boston, Massachusetts.,Department of Pathology, Brigham & Women's Hospital, Boston, Massachusetts
| | - Ahmad N Abou Tayoun
- The Children's Hospital of Philadelphia, Philadelphia, Pennsylvania.,The University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania
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16
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A systematic review of hearing and vestibular function in carriers of the Pro51Ser mutation in the COCH gene. Eur Arch Otorhinolaryngol 2019; 276:1251-1262. [DOI: 10.1007/s00405-019-05322-x] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2018] [Accepted: 01/30/2019] [Indexed: 01/08/2023]
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17
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Pawlak-Osiñska K, Linkowska K, Grzybowski T. Genes important for otoneurological diagnostic purposes - current status and future prospects. ACTA ACUST UNITED AC 2018; 38:242-250. [PMID: 29984802 DOI: 10.14639/0392-100x-1692] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2017] [Accepted: 10/12/2017] [Indexed: 11/23/2022]
Abstract
SUMMARY This review focuses on the current knowledge of the genes responsible for non-syndromic hearing loss that can be useful for otoneurological diagnostic purposes. From among a large number of genes that have been associated with non-syndromic hearing impairment, we selected several best-known genes, including the COCH gene, GJB2, GJB6 and SLC26A4, and we describe their role and effects of mutations and prevalence of mutations in various populations. Next, we focus on genes associated with tinnitus. Important areas for further research include assessment of genes potentially involved in pathophysiology of tinnitus and vertigo, which have traditionally been considered as being of otological aetiology, while advances in neuroimaging techniques have increasingly shifted studies toward neurological correlations.
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Affiliation(s)
- K Pawlak-Osiñska
- Department of Otolaryngology and Oncology Collegium Medicum in Bydgoszcz Nicolaus Copernicus University, Skłodowskiej-Curie 9, Bydgoszcz, Poland
| | - K Linkowska
- Department of Forensic Medicine Division of Molecular and Forensic Genetics Collegium Medicum in Bydgoszcz Nicolaus Copernicus University, Skłodowskiej-Curie 9, Bydgoszcz, Poland
| | - T Grzybowski
- Department of Forensic Medicine Division of Molecular and Forensic Genetics Collegium Medicum in Bydgoszcz Nicolaus Copernicus University, Skłodowskiej-Curie 9, Bydgoszcz, Poland
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18
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Mielczarek M, Olszewski J, Pietkiewicz P. Sequencing of exons 4, 5, 12 of COCH gene in patients with postlingual sensorineural hearing loss accompanied by vestibular lesion. Arch Med Sci 2018; 14:625-628. [PMID: 29765451 PMCID: PMC5949911 DOI: 10.5114/aoms.2016.60094] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/22/2015] [Accepted: 03/07/2016] [Indexed: 12/03/2022] Open
Abstract
INTRODUCTION Mutations at the DFNA9 locus on chromosome 14q12 are the third most common form of DFNA hearing loss, which is clinically characterized by late onset (in adulthood) progressive sensorineural hearing loss accompanied by vestibular dysfunction. The aim of the study was to search for COCH gene mutations (P51S, V66G, G87W, G88E, V104del, I109N, W117R, A119T, M512T, C542Y) in patients with severe or profound sensorineural hearing loss accompanied by a vestibular lesion. MATERIAL AND METHODS The study was based on a group of 30 patients. Qualification criteria comprised the presence of progressive postlingual, severe to profound sensorineural hearing loss with tinnitus, early age of sensorineural hearing loss onset, before the 40th year of life, and a positive family history of early onset hearing loss. All patients were diagnosed with peripheral vestibular lesions. RESULTS The authors did not find P51S, V66G, G87W, G88E, V104del, I109N, W117R, A119T, M512T, or C542Y mutations in the COCH gene in the tested group (no differences were found in the nucleotide sequences of exomes 4, 5 and 12 when compared to the published cDNA sequence of the COCH gene). CONCLUSIONS No cochlin mutations were found in the group of patients with severe to profound sensorineural hearing impairment accompanied by a vestibular lesion. The COCH gene needs further exploration and analysis of genotype-phenotype correlations.
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Affiliation(s)
- Marzena Mielczarek
- Department of Otolaryngology, Laryngological Oncology, Audiology and Phoniatrics, Medical University of Lodz, Lodz, Poland
| | - Jurek Olszewski
- Department of Otolaryngology, Laryngological Oncology, Audiology and Phoniatrics, Medical University of Lodz, Lodz, Poland
| | - Piotr Pietkiewicz
- Department of Otolaryngology, Laryngological Oncology, Audiology and Phoniatrics, Medical University of Lodz, Lodz, Poland
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19
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Bi-allelic inactivating variants in the COCH gene cause autosomal recessive prelingual hearing impairment. Eur J Hum Genet 2018; 26:587-591. [PMID: 29449721 DOI: 10.1038/s41431-017-0066-2] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2017] [Revised: 11/22/2017] [Accepted: 11/29/2017] [Indexed: 01/19/2023] Open
Abstract
Pathogenic variant in COCH are a known cause of DFNA9 autosomal dominant progressive hearing loss and vestibular dysfunction with adult onset. Hitherto, only dominant nonsynonymous variants and in-frame deletions with a presumed dominant negative or gain-of-function effect have been described. Here, we describe two brothers with congenital prelingual deafness and a homozygous nonsense c.292C>T(p.Arg98*) COCH variant, suggesting a loss-of-function effect. Vestibular dysfunction starting in the first decade was observed in the older patient. The heterozygous parents and sibling have normal hearing and vestibular function, except for the mother, who shows vestibular hyporeflexia and abnormal smooth pursuit tests, most likely due to concomitant disease. This is the first report of autosomal recessive inheritance of cochlea-vestibular dysfunction caused by a pathogenic variant in the COCH gene. An earlier onset of hearing impairment and vestibular dysfunction compared to the dominant hearing loss causing COCH variants is observed.
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20
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De Belder J, Matthysen S, Claes AJ, Mertens G, Van de Heyning P, Van Rompaey V. Does Otovestibular Loss in the Autosomal Dominant Disorder DFNA9 Have an Impact of on Cognition? A Systematic Review. Front Neurosci 2018; 11:735. [PMID: 29375286 PMCID: PMC5767272 DOI: 10.3389/fnins.2017.00735] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2017] [Accepted: 12/18/2017] [Indexed: 12/21/2022] Open
Abstract
Background and Purpose: Cognitive impairment has been observed in patients with bilateral vestibular loss (BVL) and in patients with sensorineural hearing loss (SNHL). DFNA9 is an autosomal dominant disorder that causes a combination of both sensory deficits by the 3rd to 5th decade. We therefore hypothesize a combined detrimental effect on cognition. The aim of this systematic review was to identify studies related to DFNA9 in general and its relationship with cognitive impairment more specifically. Materials and Methods: Several databases including Medline, Cochrane Database of Systematic Reviews, Cochrane Central Register of Controlled Trials, ISI Web of Knowledge, and Web of Science were searched to accumulate information about DFNA9-mutations, including phenotype, genotype, pathophysiology, quality of life (QOL), and imaging in general and cognitive function more specifically. A qualitative analysis was performed on the 55 articles that qualified. Results: The clinical features of DFNA9 are different along the 24 COCH mutations, described up to now. Vestibular symptoms generally present themselves a few years after SNHL onset in mutations associated with the vWFA-domain although they can precede SNHL onset in other mutations associated with the LCCL-domain. QoL has not been studied extensively in DFNA9, although scarce work is available on the positive impact of cochlear implantation to rehabilitate hearing. No studies were found evaluating cognition in DFNA9 patients. Conclusion: Although cognitive impairment has been demonstrated in patients with hearing loss as well as in patients with BVL, no studies have been reported on the combination of both sensory deficits, such as in DFNA9. Further research is warranted to correlate otovestibular status with cognition.
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Affiliation(s)
- Jonas De Belder
- Faculty of Medicine and Health Sciences, University of Antwerp, Antwerp, Belgium
| | - Stijn Matthysen
- Faculty of Medicine and Health Sciences, University of Antwerp, Antwerp, Belgium
| | - Annes J Claes
- Faculty of Medicine and Health Sciences, University of Antwerp, Antwerp, Belgium.,Department of Otorhinolaryngology and Head and Neck Surgery, Antwerp University Hospital, Edegem, Belgium
| | - Griet Mertens
- Faculty of Medicine and Health Sciences, University of Antwerp, Antwerp, Belgium.,Department of Otorhinolaryngology and Head and Neck Surgery, Antwerp University Hospital, Edegem, Belgium
| | - Paul Van de Heyning
- Faculty of Medicine and Health Sciences, University of Antwerp, Antwerp, Belgium.,Department of Otorhinolaryngology and Head and Neck Surgery, Antwerp University Hospital, Edegem, Belgium
| | - Vincent Van Rompaey
- Faculty of Medicine and Health Sciences, University of Antwerp, Antwerp, Belgium.,Department of Otorhinolaryngology and Head and Neck Surgery, Antwerp University Hospital, Edegem, Belgium
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21
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Parzefall T, Frohne A, Koenighofer M, Kirchnawy A, Streubel B, Schoefer C, Gstoettner W, Frei K, Lucas T. Identification of a rare COCH mutation by whole-exome sequencing : Implications for personalized therapeutic rehabilitation in an Austrian family with non-syndromic autosomal dominant late-onset hearing loss. Wien Klin Wochenschr 2017; 130:299-306. [PMID: 28733840 PMCID: PMC5966484 DOI: 10.1007/s00508-017-1230-y] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2017] [Accepted: 06/26/2017] [Indexed: 12/24/2022]
Abstract
Background Non-syndromic autosomal dominant hearing impairment is characteristically postlingual in onset. Genetic diagnostics are essential for genetic counselling, disease prognosis and understanding of the molecular mechanisms of disease. To date, 36 causative genes have been identified, many in only individual families. Gene selection for genetic screening by traditional methods and genetic diagnosis in autosomal dominant patients has therefore been fraught with difficulty. Whole-exome sequencing provides a powerful tool to analyze all protein-coding genomic regions in parallel, thus allowing the comprehensive screening of all known genes and associated alterations. Methods In this study, a previously undiagnosed late-onset progressive autosomal dominant hearing loss in an Austrian family was investigated by means of whole-exome sequencing. Results were confirmed by Sanger sequencing. Results A previously described c.151C>T missense (p.Pro51Ser) mutation in the LCCL (limulus factor C, cochlin, late gestation lung protein Lgl1) domain of the cochlin gene (COCH) was identified as causative and segregated with disease in five members of the family. Molecular diagnostics led to the decision to perform cochlear implantation in an index patient who subsequently showed excellent postoperative auditory performance. The c.151C>T mutation was not found in 18 screened Austrian families with autosomal dominant hearing loss but was represented alongside other known pathogenic mutant COCH alleles in the Genome Aggregation Database (gnomAD) in European populations. A combined allele frequency of 0.000128 implies an orphan disease frequency for COCH-induced hearing loss of 1:3900 in Europe. Conclusions Exome sequencing successfully resolved the genetic diagnosis in a family suffering from autosomal dominant hearing impairment and allowed prediction of purported auditory outcome after cochlear implantation in an index patient. Personalized treatment approaches based on the molecular mechanisms of disease may become increasingly important in the future.
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Affiliation(s)
- Thomas Parzefall
- Department of Otorhinolaryngology, Head and Neck Surgery, Medical University of Vienna, Waehringer Guertel 18-20, 1090, Vienna, Austria
| | - Alexandra Frohne
- Department for Cell and Developmental Biology, Orphan disease genetics group, Center for Anatomy and Cell Biology, Medical University of Vienna, Vienna, Austria
| | - Martin Koenighofer
- Department of Otorhinolaryngology, Head and Neck Surgery, Medical University of Vienna, Waehringer Guertel 18-20, 1090, Vienna, Austria
| | - Andreas Kirchnawy
- Department for Cell and Developmental Biology, Orphan disease genetics group, Center for Anatomy and Cell Biology, Medical University of Vienna, Vienna, Austria
| | - Berthold Streubel
- Clinical Institute of Pathology, Medical University of Vienna, Vienna, Austria
| | - Christian Schoefer
- Department for Cell and Developmental Biology, Orphan disease genetics group, Center for Anatomy and Cell Biology, Medical University of Vienna, Vienna, Austria
| | - Wolfgang Gstoettner
- Department of Otorhinolaryngology, Head and Neck Surgery, Medical University of Vienna, Waehringer Guertel 18-20, 1090, Vienna, Austria
| | - Klemens Frei
- Department of Otorhinolaryngology, Head and Neck Surgery, Medical University of Vienna, Waehringer Guertel 18-20, 1090, Vienna, Austria.
| | - Trevor Lucas
- Department for Cell and Developmental Biology, Orphan disease genetics group, Center for Anatomy and Cell Biology, Medical University of Vienna, Vienna, Austria
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22
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Massively Parallel Sequencing of a Chinese Family with DFNA9 Identified a Novel Missense Mutation in the LCCL Domain of COCH. Neural Plast 2016; 2016:5310192. [PMID: 28116169 PMCID: PMC5223038 DOI: 10.1155/2016/5310192] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2016] [Revised: 11/16/2016] [Accepted: 11/23/2016] [Indexed: 11/25/2022] Open
Abstract
DFNA9 is a late-onset, progressive, autosomal dominantly inherited sensorineural hearing loss with vestibular dysfunction, which is caused by mutations in the COCH (coagulation factor C homology) gene. In this study, we investigated a Chinese family segregating autosomal dominant nonsyndromic sensorineural hearing loss. We identified a missense mutation c.T275A p.V92D in the LCCL domain of COCH cosegregating with the disease and absent in 100 normal hearing controls. This mutation leads to substitution of the hydrophobic valine to an acidic amino acid aspartic acid. Our data enriched the mutation spectrum of DFNA9 and implied the importance for mutation screening of COCH in age related hearing loss with vestibular dysfunctions.
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23
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Masuda M, Mutai H, Arimoto Y, Nakano A, Matsunaga T. A novel frameshift variant of COCH supports the hypothesis that haploinsufficiency is not a cause of autosomal dominant nonsyndromic deafness 9. Biochem Biophys Res Commun 2015; 469:270-4. [PMID: 26631968 DOI: 10.1016/j.bbrc.2015.11.106] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2015] [Accepted: 11/23/2015] [Indexed: 11/25/2022]
Abstract
COCH (coagulation factor C homology) encodes cochlin, and certain mutations of COCH cause autosomal dominant nonsyndromic deafness 9 (DFNA9). Hearing loss due to COCH mutation begins in adulthood, and 17 missense mutations and two in-frame mutations have been reported. Studies with animal and cellular models have suggested that the underlying biological mechanism of DFNA9 is the dominant-negative effect of mutated COCH and not haploinsufficiency. However, no human cases of DFNA9 that support this hypothesis have been reported. The proband of the present case was an 18-year-old male with congenital or infantile hearing loss. Targeted next-generation sequencing analysis detected a heterozygous novel frameshift mutation of COCH (c.146dupT, p.C50LfsX8) in the proband, whose hearing loss began earlier than what is typical for DFNA9. His mother also carried the mutation but had normal hearing. Consequently, the mutation was not considered to be the cause of the proband's hearing loss. This family is the first case of a truncating COCH variant and supports the hypothesis that COCH haploinsufficiency is not the cause of hearing loss in humans.
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Affiliation(s)
- Masatsugu Masuda
- Laboratory of Auditory Disorders, National Institute of Sensory Organs, National Hospital Organization Tokyo Medical Center, 2-5-1 Higashigaoka Meguro-ku, Tokyo 152-8902, Japan; Department of Otolaryngology, School of Medicine, Kyorin University, 6-20-2 Shinkawa, Mitaka-shi, Tokyo 181-8611, Japan.
| | - Hideki Mutai
- Laboratory of Auditory Disorders, National Institute of Sensory Organs, National Hospital Organization Tokyo Medical Center, 2-5-1 Higashigaoka Meguro-ku, Tokyo 152-8902, Japan.
| | - Yukiko Arimoto
- Department of Otolaryngology, Chiba Children's Hospital, 579-1 Hetacho, Midori-ku, Chiba-shi, Chiba 266-0007, Japan.
| | - Atsuko Nakano
- Department of Otolaryngology, Chiba Children's Hospital, 579-1 Hetacho, Midori-ku, Chiba-shi, Chiba 266-0007, Japan.
| | - Tatsuo Matsunaga
- Laboratory of Auditory Disorders, National Institute of Sensory Organs, National Hospital Organization Tokyo Medical Center, 2-5-1 Higashigaoka Meguro-ku, Tokyo 152-8902, Japan; Medical Genetics Center, National Hospital Organization Tokyo Medical Center, 2-5-1 Higashigaoka Meguro-ku, Tokyo 152-8902, Japan.
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24
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Jung J, Kim HS, Lee MG, Yang EJ, Choi JY. NovelCOCHp.V123E Mutation, Causative of DFNA9 Sensorineural Hearing Loss and Vestibular Disorder, Shows Impaired Cochlin Post-Translational Cleavage and Secretion. Hum Mutat 2015; 36:1168-75. [DOI: 10.1002/humu.22855] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2015] [Accepted: 07/27/2015] [Indexed: 01/07/2023]
Affiliation(s)
- Jinsei Jung
- Department of Otorhinolaryngology; Yonsei University College of Medicine; Seoul Republic of Korea
| | - Han Sang Kim
- Department of Pharmacology; Yonsei University College of Medicine; Seoul Republic of Korea
- Brain Korea 21 PLUS Project for Medical Science; Yonsei University College of Medicine; Seoul Republic of Korea
| | - Min Goo Lee
- Department of Pharmacology; Yonsei University College of Medicine; Seoul Republic of Korea
- Brain Korea 21 PLUS Project for Medical Science; Yonsei University College of Medicine; Seoul Republic of Korea
| | - Eun Jin Yang
- Clinical Research Division; Korea Institute of Oriental Medicine; Daejeon Republic of Korea
| | - Jae Young Choi
- Department of Otorhinolaryngology; Yonsei University College of Medicine; Seoul Republic of Korea
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25
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Bae SH, Robertson NG, Cho HJ, Morton CC, Jung DJ, Baek JI, Choi SY, Lee J, Lee KY, Kim UK. Identification of pathogenic mechanisms of COCH mutations, abolished cochlin secretion, and intracellular aggregate formation: genotype-phenotype correlations in DFNA9 deafness and vestibular disorder. Hum Mutat 2015; 35:1506-1513. [PMID: 25230692 DOI: 10.1002/humu.22701] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2014] [Accepted: 09/08/2014] [Indexed: 11/06/2022]
Abstract
Mutations in COCH (coagulation factor C homology) cause autosomal-dominant nonsyndromic hearing loss with variable degrees of clinical onset and vestibular malfunction. We selected eight uncharacterized mutations and performed immunocytochemical and Western blot analyses to track cochlin through the secretory pathway. We then performed a comprehensive analysis of clinical information from DFNA9 patients with all 21 known COCH mutations in conjunction with cellular and molecular findings to identify genotype-phenotype correlations. Our studies revealed that five mutants were not secreted into the media: two von Willebrand factor A (vWFA) domain mutants, which were not transported from the endoplasmic reticulum to Golgi complex and formed high-molecular-weight aggregates in cell lysates, and three LCCL domain mutants, which were detected as intracellular dimeric cochlins. Mutant cochlins that were not secreted and accumulated in cells result in earlier age of onset of hearing defects. In addition, individuals with LCCL domain mutations show accompanying vestibular dysfunction, whereas those with vWFA domain mutations exhibit predominantly hearing loss. This is the first report showing failure of mutant cochlin transport through the secretory pathway, abolishment of cochlin secretion, and formation and retention of dimers and large multimeric intracellular aggregates, and high correlation with earlier onset and progression of hearing loss in individuals with these DFNA9-causing mutations.
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Affiliation(s)
- Seung-Hyun Bae
- Department of Biology, College of Natural Sciences, Kyungpook National University, Daegu, South Korea.,School of Life Sciences, KNU Creative BioResearch Group (BK21 plus program), Kyungpook National University
| | - Nahid G Robertson
- Department of Obstetrics & Gynecology, Brigham & Women's Hospital, Boston, MA, USA
| | - Hyun-Ju Cho
- Department of Biology, College of Natural Sciences, Kyungpook National University, Daegu, South Korea
| | - Cynthia C Morton
- Departments of Obstetrics & Gynecology and Pathology, Brigham & Women's Hospital, Harvard Medical School, Boston, MA, Broad Institute, Cambridge, MA, USA
| | - Da Jung Jung
- Department of Otolaryngology, College of Medicine, Kyungpook National University, Daegu, South Korea
| | - Jeong-In Baek
- Department of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Soo-Young Choi
- Department of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Jaetae Lee
- Department of Nuclear Medicine, Kyungpook National University School of Medicine, Daegu, Republic of Korea
| | - Kyu-Yup Lee
- Department of Otolaryngology, College of Medicine, Kyungpook National University, Daegu, South Korea
| | - Un-Kyung Kim
- Department of Biology, College of Natural Sciences, Kyungpook National University, Daegu, South Korea.,School of Life Sciences, KNU Creative BioResearch Group (BK21 plus program), Kyungpook National University
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26
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Robertson NG, O’Malley JT, Ong CA, Giersch AB, Shen J, Stankovic KM, Morton CC. Cochlin in normal middle ear and abnormal middle ear deposits in DFNA9 and Coch (G88E/G88E) mice. J Assoc Res Otolaryngol 2014; 15:961-74. [PMID: 25049087 PMCID: PMC4389958 DOI: 10.1007/s10162-014-0481-9] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2013] [Accepted: 07/01/2014] [Indexed: 12/18/2022] Open
Abstract
DFNA9 sensorineural hearing loss and vestibular disorder, caused by mutations in COCH, has a unique identifying histopathology including prominent acellular deposits in cochlear and vestibular labyrinths. A recent study has shown presence of deposits also in middle ear structures of DFNA9-affected individuals (McCall et al., J Assoc Res Otolaryngol 12:141-149, 2004). To investigate the possible role of cochlin in the middle ear and in relation to aggregate formation, we evaluated middle ear histopathology in our Coch knock-in (Coch (G88E/G88E) ) mouse model, which harbors one of the DFNA9-causative mutations. Our findings reveal accumulation of acellular deposits in the incudomalleal and incudostapedial joints in Coch (G88E/G88E) mice, similar to those found in human DFNA9-affected temporal bones. Aggregates are absent in negative control Coch (+/+) and Coch (-/-) mice. Thickening of the tympanic membrane (TM) found in humans with DFNA9 was not appreciably detected in Coch (G88E/G88E) mice at the evaluated age. We investigated cochlin localization first in the Coch (+/+)mouse and in normal human middle ears, and found prominent and specific cochlin staining in the incudomalleal joint, incudostapedial joint, and the pars tensa of the TM, which are the three sites where abnormal deposits are detected in DFNA9-affected middle ears. Cochlin immunostaining of Coch (G88E/G88E) and DFNA9-affected middle ears showed mutant cochlin localization within areas of aggregates. Cochlin staining was heterogeneous throughout DFNA9 middle ear deposits, which appear as unorganized and overlapping mixtures of both eosinophilic and basophilic substances. Immunostaining for type II collagen colocalized with cochlin in pars tensa of the tympanic membrane. In contrast, immunostaining for type II collagen did not overlap with cochlin in interossicular joints, where type II collagen was localized in the region of the chondrocytes, but not in the thin layer of the articular surface of the ossicles nor in the eosinophilic deposits with specific cochlin staining.
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Affiliation(s)
- Nahid G. Robertson
- />Department of Obstetrics, Gynecology and Reproductive Biology, Brigham and Women’s Hospital, Harvard Medical School, 77 Avenue Louis Pasteur, NRB 160, Boston, MA 02115 USA
| | - Jennifer T. O’Malley
- />Department of Otolaryngology, Massachusetts Eye and Ear Infirmary, Boston, MA USA
| | - Cheng Ai Ong
- />Department of Otolaryngology, Massachusetts Eye and Ear Infirmary, Boston, MA USA
- />Department of Otology and Laryngology, Harvard Medical School, Boston, MA USA
| | - Anne B.S. Giersch
- />Department of Pathology, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA USA
| | - Jun Shen
- />Department of Pathology, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA USA
| | - Konstantina M. Stankovic
- />Department of Otolaryngology, Massachusetts Eye and Ear Infirmary, Boston, MA USA
- />Department of Otology and Laryngology, Harvard Medical School, Boston, MA USA
| | - Cynthia C. Morton
- />Department of Obstetrics, Gynecology and Reproductive Biology, Brigham and Women’s Hospital, Harvard Medical School, 77 Avenue Louis Pasteur, NRB 160, Boston, MA 02115 USA
- />Department of Pathology, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA USA
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27
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Py BF, Gonzalez SF, Long K, Kim MS, Kim YA, Zhu H, Yao J, Degauque N, Villet R, Ymele-Leki P, Gadjeva M, Pier GB, Carroll MC, Yuan J. Cochlin produced by follicular dendritic cells promotes antibacterial innate immunity. Immunity 2013; 38:1063-72. [PMID: 23684986 DOI: 10.1016/j.immuni.2013.01.015] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2012] [Accepted: 01/14/2013] [Indexed: 01/03/2023]
Abstract
Cochlin, an extracellular matrix protein, shares homologies with the Factor C, a serine protease found in horseshoe crabs, which is critical for antibacterial responses. Mutations in the COCH gene are responsible for human DFNA9 syndrome, a disorder characterized by neurodegeneration of the inner ear that leads to hearing loss and vestibular impairments. The physiological function of cochlin, however, is unknown. Here, we report that cochlin is specifically expressed by follicular dendritic cells and selectively localized in the fine extracellular network of conduits in the spleen and lymph nodes. During inflammation, cochlin was cleaved by aggrecanases and secreted into blood circulation. In models of lung infection with Pseudomonas aeruginosa and Staphylococcus aureus, Coch(-/-) mice show reduced survival linked to defects in local cytokine production, recruitment of immune effector cells, and bacterial clearance. By producing cochlin, FDCs thus contribute to the innate immune response in defense against bacteria.
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Affiliation(s)
- Bénédicte F Py
- Department of Cell Biology, Harvard Medical School, Boston, MA 02115, USA.
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28
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Gallant E, Francey L, Fetting H, Kaur M, Hakonarson H, Clark D, Devoto M, Krantz ID. Novel COCH mutation in a family with autosomal dominant late onset sensorineural hearing impairment and tinnitus. Am J Otolaryngol 2013; 34:230-5. [PMID: 23374487 DOI: 10.1016/j.amjoto.2012.11.002] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2012] [Accepted: 11/05/2012] [Indexed: 11/18/2022]
Abstract
This report describes a three generation family with late onset bilateral sensorineural hearing impairment (BLSNHI) and tinnitus in which a novel mutation in the COCH gene was identified after a genome-wide linkage approach. The COCH gene is one of the few genes clinically examined when investigating the etiology of autosomal dominant late onset hearing impairment. Initially mutations in the COCH gene were only reported in exons 4 and 5, coding for the LCCL protein domain. More recently, additional mutations have been identified in exon 12, the only mutations identified outside of the LCCL domain. Currently clinical genetic testing for the COCH gene primarily focuses on identifying mutations in these three exons. In this study, we identify a novel mutation in the COCH gene in exon 11, which, like the exon 12 mutations, falls within the vWFA2 protein domain. This finding reinforces the need for clinical genetic screening of the COCH gene to be expanded beyond the current limited exon screening, as there is now more evidence to support that mutations in other areas of this gene are also causative of a similar form of late onset BLSNHI.
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Affiliation(s)
- Emily Gallant
- Division of Human Genetics, The Children's Hospital of Philadelphia, Philadelphia, PA, USA
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Shiiba K, Shindo S, Ikezono T, Sekine K, Matsumura T, Sekiguchi S, Yagi T, Okubo K. Cochlin expression in the rat perilymph during postnatal development. Acta Otolaryngol 2012; 132:1134-9. [PMID: 23020749 DOI: 10.3109/00016489.2012.687456] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
CONCLUSIONS The changes in the cochlin isoforms in the perilymph may provide important insights to the understanding of cochlin function and the pathogenesis of related inner ear diseases. OBJECTIVES Cochlin is involved in various pathologies of the inner ear. Altered levels of cochlin isoforms in developing inner ear tissue were reported previously. The purpose of this study was to elucidate the cochlin isoform expression in the perilymph of rats during postnatal development in relation to Coch gene mRNA expression. METHODS We studied the cochlin isoforms in the rat perilymph during postnatal development by Western blot analysis. Real-time PCR was also performed to elucidate the expression level of Coch mRNA in the developing inner ear of rats. RESULTS Western blot analysis showed that the expression of p63s in the perilymph was highest on the 12th day after birth (DAB12), the earliest age at which we could identify the perilymphatic space microscopically, and it decreased gradually as the cochlea developed. On the other hand, the expression of Cochlin-tomoprotein (CTP)was lowest on DAB12 and increased gradually up to DAB24. COCH mRNA was detected from DAB3 and gradually increased to DAB15, and then gradually decreased to DAB70.
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Affiliation(s)
- Kyoko Shiiba
- Department of Otorhinolaryngology, Nippon Medical School, Tokyo, Japan
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Gao J, Xue J, Chen L, Ke X, Qi Y, Liu Y. Whole exome sequencing identifies a novelDFNA9mutation, C162Y. Clin Genet 2012; 83:477-81. [PMID: 22931125 DOI: 10.1111/cge.12006] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2012] [Revised: 08/27/2012] [Accepted: 08/27/2012] [Indexed: 11/29/2022]
Affiliation(s)
| | | | | | | | - Y Qi
- Laboratory Center; Peking University First Hospital; Beijing; China
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Pauw RJ, Huygen PLM, Colditz GM, Cremers CWRJ. Phenotype analysis of an Australian DFNA9 family with the 1109N COCH mutation. Ann Otol Rhinol Laryngol 2011; 120:414-21. [PMID: 21774451 DOI: 10.1177/000348941112000612] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
OBJECTIVES We studied the clinical characteristics of an Australian family with an autosomal dominant sensorineural hearing impairment (DFNA9) caused by an I109N mutation in COCH. METHODS Retrospective analyses of audiometric data from 8 mutation carriers of an Australian DFNA9 family with the I109N COCH mutation were performed. Cross-sectional hearing levels related to age, age-related typical audiograms, and speech recognition scores related to age and to the level of hearing impairment were investigated. Data were compared to those obtained in previously identified DFNA9 families with P51S, V66G, G87W, G88E, I109T, and C542F COCH mutations. RESULTS Deterioration of hearing in the I109N mutation carriers started before the age of 40 years. The audiometric characteristics of the I109N mutation carriers are essentially similar to those previously established in I109T mutation carriers and, to a lesser extent, in P51S, G87W, and G88E mutation carriers. CONCLUSIONS The phenotype associated with the I109N COCH mutation is largely similar to that associated with the I109T, P51S, G87W, and G88E mutation carriers. However, subtle differences seem to exist in terms of age of onset and rate of progression.
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Affiliation(s)
- Robert J Pauw
- Department of Otorhinolaryngology, Radboud University Nijmegen Medical Center, Nijmegen, The Netherlands
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Hildebrand MS, Gandolfo L, Shearer AE, Webster JA, Jensen M, Kimberling WJ, Stephan D, Huygen PLM, Smith RJH, Bahlo M. A novel mutation in COCH-implications for genotype-phenotype correlations in DFNA9 hearing loss. Laryngoscope 2011; 120:2489-93. [PMID: 21046548 DOI: 10.1002/lary.21159] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
OBJECTIVES/HYPOTHESIS To determine the cause of autosomal dominant hearing loss segregating in an American family. STUDY DESIGN Family study. METHODS Otologic and audiometric examination was performed on affected family members. Genome wide parametric multipoint linkage mapping using a dominant model was performed with Affymetrix 50K GeneChip data. Direct sequencing was used to confirm the causative mutation. RESULTS In American family 467, segregating autosomal dominant nonsyndromic hearing loss, a novel heterozygous missense mutation (c.362T>C; p.F121S) was identified in the COCH gene. This mutation was also associated with vestibular dysfunction typical of other DFNA9 families. However, affected family members also exhibited memory loss and night blindness. CONCLUSIONS The novel COCH mutation affects the functionally important limulus factor C, Coch-5b2 and Lgl1 domain where most DFNA9 mutations have been localized. The onset of the hearing loss, in the 2nd or 3rd decade of life, is earlier than in most DFNA9 families. The progression of hearing loss and vestibular dysfunction in the American family is typical of other DFNA9 families with mutations in this domain. Memory loss and night blindness have not been previously reported in DFNA9 families.
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Affiliation(s)
- Michael S Hildebrand
- Department of Otolaryngology-Head and Neck Surgery, University of Iowa, Iowa City, Iowa, USA
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Jones SM, Robertson NG, Given S, Giersch ABS, Liberman MC, Morton CC. Hearing and vestibular deficits in the Coch(-/-) null mouse model: comparison to the Coch(G88E/G88E) mouse and to DFNA9 hearing and balance disorder. Hear Res 2010; 272:42-8. [PMID: 21073934 DOI: 10.1016/j.heares.2010.11.002] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/27/2010] [Revised: 10/28/2010] [Accepted: 11/02/2010] [Indexed: 10/18/2022]
Abstract
Two mouse models, the Coch(G88E/G88E) or "knock-in" and the Coch(-/-) or "knock-out" (Coch null), have been developed to study the human late-onset, progressive, sensorineural hearing loss and vestibular dysfunction known as DFNA9. This disorder results from missense and in-frame deletion mutations in COCH (coagulation factor C homology), encoding cochlin, the most abundantly detected protein in the inner ear. We have performed hearing and vestibular analyses by auditory brainstem response (ABR) and vestibular evoked potential (VsEP) testing of the Coch(-/-) and Coch(G88E/G88E) mouse models. Both Coch(-/-) and Coch(G88E/G88E) mice show substantially elevated ABRs at 21 months of age, but only at the highest frequency tested for the former and all frequencies for the latter. At 21 months, 9 of 11 Coch(-/-) mice and 4 of 8 Coch(G88E/G88E) mice have absent ABRs. Interestingly Coch(-/+) mice do not show hearing deficits, in contrast to Coch(G88E/+), which demonstrate elevated ABR thresholds similar to homozyotes. These results corroborate the DFNA9 autosomal dominant mode of inheritance, in addition to the observation that haploinsufficiency of Coch does not result in impaired hearing. Vestibular evoked potential (VsEP) thresholds were analyzed using a two factor ANOVA (Age X Genotype). Elevated VsEP thresholds are detected in Coch(-/-) mice at 13 and 21 months, the two ages tested, and as early as seven months in the Coch(G88E/G88E) mice. These results indicate that in both mouse models, vestibular function is compromised before cochlear function. Analysis and comparison of hearing and vestibular function in these two DFNA9 mouse models, where deficits occur at such an advanced age, provide insight into the pathology of DFNA9 and age-related hearing loss and vestibular dysfunction as well as an opportunity to investigate potential interventional therapies.
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Affiliation(s)
- Sherri M Jones
- Department of Communication Sciences and Disorders, East Carolina University, Greenville, NC, USA
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McCall AA, Linthicum FH, O'Malley JT, Adams JC, Merchant SN, Bassim MK, Gellibolian R, Fayad JN. Extralabyrinthine manifestations of DFNA9. J Assoc Res Otolaryngol 2010; 12:141-9. [PMID: 21052762 DOI: 10.1007/s10162-010-0245-0] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2010] [Accepted: 10/20/2010] [Indexed: 12/20/2022] Open
Abstract
DFNA9 is an autosomal dominant cause of non-syndromic adult-onset sensorineural hearing loss with associated variable vestibular dysfunction caused by mutations in the COCH gene. DFNA9 has previously been characterized by the presence of unique histopathologic features limited to the cochlear and vestibular labyrinth. This report describes newly discovered extralabyrinthine findings within the middle ear in DFNA9 and discusses their implications. The histopathologic anatomy of extralabyrinthine structures was reviewed in 12 temporal bones from seven individuals with DFNA9 and compared with age-matched controls. All temporal bones with DFNA9 had abnormal deposits within the tympanic membrane, incudomalleal joint, and incudostapedial joint. Hematoxylin and eosin stain and Movat's pentachrome stain both revealed different staining patterns of the extralabyrinthine deposits compared with the intralabyrinthine deposits suggesting that the composition of the deposits varies with location. The deposits within the tympanic membrane resembled cartilage morphologically and stained positively for aggrecan, an extracellular matrix protein found in cartilage. However, the cellular component of the tympanic membrane deposits did not stain with immunomarkers for chondrocytes (s100 and connective tissue growth factor). These novel findings in DFNA9 have implications for the phenotypic expression of the disorder and the clinical workup of adult-onset sensorineural hearing loss.
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Affiliation(s)
- Andrew A McCall
- Department of Otolaryngology, Massachusetts Eye and Ear Infirmary, 243 Charles Street, Boston, MA 02114, USA.
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