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Homma K. The Pathological Mechanisms of Hearing Loss Caused by KCNQ1 and KCNQ4 Variants. Biomedicines 2022; 10:biomedicines10092254. [PMID: 36140355 PMCID: PMC9496569 DOI: 10.3390/biomedicines10092254] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2022] [Revised: 09/08/2022] [Accepted: 09/09/2022] [Indexed: 11/29/2022] Open
Abstract
Deafness-associated genes KCNQ1 (also associated with heart diseases) and KCNQ4 (only associated with hearing loss) encode the homotetrameric voltage-gated potassium ion channels Kv7.1 and Kv7.4, respectively. To date, over 700 KCNQ1 and over 70 KCNQ4 variants have been identified in patients. The vast majority of these variants are inherited dominantly, and their pathogenicity is often explained by dominant-negative inhibition or haploinsufficiency. Our recent study unexpectedly identified cell-death-inducing cytotoxicity in several Kv7.1 and Kv7.4 variants. Elucidation of this cytotoxicity mechanism and identification of its modifiers (drugs) have great potential for aiding the development of a novel pharmacological strategy against many pathogenic KCNQ variants. The purpose of this review is to disseminate this emerging pathological role of Kv7 variants and to underscore the importance of experimentally characterizing disease-associated variants.
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Affiliation(s)
- Kazuaki Homma
- Department of Otolaryngology-Head and Neck Surgery, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611, USA; ; Tel.: +1-312-503-5344
- The Hugh Knowles Center for Clinical and Basic Science in Hearing and Its Disorders, Northwestern University, Evanston, IL 60608, USA
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Li Q, Liang P, Wang S, Li W, Wang J, Yang Y, An X, Chen J, Zha D. A novel KCNQ4 gene variant (c.857A>G; p.Tyr286Cys) in an extended family with non‑syndromic deafness 2A. Mol Med Rep 2021; 23:420. [PMID: 33846771 PMCID: PMC8025472 DOI: 10.3892/mmr.2021.12059] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2020] [Accepted: 03/04/2021] [Indexed: 12/17/2022] Open
Abstract
Deafness is one of the most common sensory disorders found in humans; notably, >60% of all cases of deafness have been attributed to genetic factors. Variants in potassium voltage-gated channel subfamily Q member 4 (KCNQ4) are etiologically linked to a type of progressive hearing loss, deafness non-syndromic autosomal dominant 2A (DFNA2A). In the present study, whole-exome sequencing (WES) was performed on three members of a five-generation Chinese family with 46 members with hearing loss. Pure tone audiometry and Sanger sequencing were performed for 11 family members to determine whether the novel variant in the KCNQ4 gene was segregated with the affected family members. In addition, evolutionary conservation analysis and computational tertiary structure protein prediction of the wild-type KCNQ4 protein and its variant were performed. The family exhibited autosomal dominant, progressive, post-lingual, non-syndromic sensorineural hearing loss. A novel co-segregating heterozygous missense variant (c.857A>G; p.Tyr286Cys) in the glycine-tyrosine-glycine signature sequence in the pore region of the KCNQ4 channel was identified. This variant was predicted to result in a tyrosine-to-cysteine substitution at position 286 in the KCNQ4 protein. The tyrosine at position 286 is well conserved across different species. The substitution of tyrosine with cysteine would affect the structure of the pore region, resulting in the loss of channel function. The KCNQ4 gene is one of the most common mutated genes observed in patients with autosomal dominant, non-syndromic hearing loss. Taken together, for the family analyzed in the present study, performing WES in conjunction with Sanger sequencing has led to the detection of a novel, potentially causative variant (c.857 A>G; p.Tyr286Cys) in exon 6 of the KCNQ4 gene. The present study has added to the number of pathogenic variants observed in the KCNQ4 gene, and the findings may prove to be useful for both the diagnosis of DFNA2A and in the design of early interventional therapies.
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Affiliation(s)
- Qiong Li
- Department of Otolaryngology‑Head and Neck Surgery, Xijing Hospital, Air Force Medical University, Xi'an, Shaanxi 710032, P.R. China
| | - Pengfei Liang
- Department of Otolaryngology‑Head and Neck Surgery, Xijing Hospital, Air Force Medical University, Xi'an, Shaanxi 710032, P.R. China
| | - Shujuan Wang
- Department of Otolaryngology‑Head and Neck Surgery, Xijing Hospital, Air Force Medical University, Xi'an, Shaanxi 710032, P.R. China
| | - Wei Li
- Department of Otolaryngology‑Head and Neck Surgery, Xijing Hospital, Air Force Medical University, Xi'an, Shaanxi 710032, P.R. China
| | - Jian Wang
- Department of Otolaryngology‑Head and Neck Surgery, Xijing Hospital, Air Force Medical University, Xi'an, Shaanxi 710032, P.R. China
| | - Yang Yang
- Department of Otolaryngology‑Head and Neck Surgery, Xijing Hospital, Air Force Medical University, Xi'an, Shaanxi 710032, P.R. China
| | - Xiaogang An
- Department of Otolaryngology‑Head and Neck Surgery, Xijing Hospital, Air Force Medical University, Xi'an, Shaanxi 710032, P.R. China
| | - Jun Chen
- Department of Otolaryngology‑Head and Neck Surgery, Xijing Hospital, Air Force Medical University, Xi'an, Shaanxi 710032, P.R. China
| | - Dingjun Zha
- Department of Otolaryngology‑Head and Neck Surgery, Xijing Hospital, Air Force Medical University, Xi'an, Shaanxi 710032, P.R. China
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Jung J, Lin H, Koh YI, Ryu K, Lee JS, Rim JH, Choi HJ, Lee HJ, Kim HY, Yu S, Jin H, Lee JH, Lee MG, Namkung W, Choi JY, Gee HY. Rare KCNQ4 variants found in public databases underlie impaired channel activity that may contribute to hearing impairment. Exp Mol Med 2019; 51:1-12. [PMID: 31434872 PMCID: PMC6802650 DOI: 10.1038/s12276-019-0300-9] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2018] [Revised: 04/01/2019] [Accepted: 05/06/2019] [Indexed: 02/08/2023] Open
Abstract
KCNQ4 is frequently mutated in autosomal dominant non-syndromic hearing loss (NSHL), a typically late-onset, initially high-frequency loss that progresses over time (DFNA2). Most KCNQ4 mutations linked to hearing loss are clustered around the pore region of the protein and lead to loss of KCNQ4-mediated potassium currents. To understand the contribution of KCNQ4 variants to NSHL, we surveyed public databases and found 17 loss-of-function and six missense KCNQ4 variants affecting amino acids around the pore region. The missense variants have not been reported as pathogenic and are present at a low frequency (minor allele frequency < 0.0005) in the population. We examined the functional impact of these variants, which, interestingly, induced a reduction in potassium channel activity without altering expression or trafficking of the channel protein, being functionally similar to DFNA2-associated KCNQ4 mutations. Therefore, these variants may be risk factors for late-onset hearing loss, and individuals harboring any one of these variants may develop hearing loss during adulthood. Reduced channel activity could be rescued by KCNQ activators, suggesting the possibility of medical intervention. These findings indicate that KCNQ4 variants may contribute more to late-onset NSHL than expected, and therefore, genetic screening for this gene is important for the prevention and treatment of NSHL.
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Affiliation(s)
- Jinsei Jung
- Department of Otorhinolaryngology, Brain Korea 21 PLUS Project for Medical Sciences, Yonsei University College of Medicine, Seoul, 03722, Korea
| | - Haiyue Lin
- Department of Otorhinolaryngology, Brain Korea 21 PLUS Project for Medical Sciences, Yonsei University College of Medicine, Seoul, 03722, Korea
| | - Young Ik Koh
- Department of Pharmacology, Brain Korea 21 PLUS Project for Medical Sciences, Yonsei University College of Medicine, Seoul, 03722, Korea
| | - Kunhi Ryu
- Yonsei University College of Pharmacy, Incheon, 21983, Korea
| | - Joon Suk Lee
- Department of Pharmacology, Brain Korea 21 PLUS Project for Medical Sciences, Yonsei University College of Medicine, Seoul, 03722, Korea
| | - John Hoon Rim
- Department of Pharmacology, Brain Korea 21 PLUS Project for Medical Sciences, Yonsei University College of Medicine, Seoul, 03722, Korea
| | - Hye Ji Choi
- Department of Otorhinolaryngology, Brain Korea 21 PLUS Project for Medical Sciences, Yonsei University College of Medicine, Seoul, 03722, Korea
| | - Hak Joon Lee
- Department of Otorhinolaryngology, Brain Korea 21 PLUS Project for Medical Sciences, Yonsei University College of Medicine, Seoul, 03722, Korea
| | - Hye-Youn Kim
- Department of Pharmacology, Brain Korea 21 PLUS Project for Medical Sciences, Yonsei University College of Medicine, Seoul, 03722, Korea
| | - Seyoung Yu
- Department of Pharmacology, Brain Korea 21 PLUS Project for Medical Sciences, Yonsei University College of Medicine, Seoul, 03722, Korea
| | - Hyunsoo Jin
- Yonsei University College of Medicine, Seoul, 03722, Korea
| | - Ji Hyun Lee
- Department of Dermatology, Seoul St. Mary's Hospital, College of Medicine, The Catholic University of Korea, Seoul, 03722, Korea
| | - Min Goo Lee
- Department of Pharmacology, Brain Korea 21 PLUS Project for Medical Sciences, Yonsei University College of Medicine, Seoul, 03722, Korea
| | - Wan Namkung
- Yonsei University College of Pharmacy, Incheon, 21983, Korea
| | - Jae Young Choi
- Department of Otorhinolaryngology, Brain Korea 21 PLUS Project for Medical Sciences, Yonsei University College of Medicine, Seoul, 03722, Korea.
| | - Heon Yung Gee
- Department of Pharmacology, Brain Korea 21 PLUS Project for Medical Sciences, Yonsei University College of Medicine, Seoul, 03722, Korea.
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Whole-exome sequencing identifies two novel mutations in KCNQ4 in individuals with nonsyndromic hearing loss. Sci Rep 2018; 8:16659. [PMID: 30413759 PMCID: PMC6226507 DOI: 10.1038/s41598-018-34876-9] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2018] [Accepted: 10/27/2018] [Indexed: 11/09/2022] Open
Abstract
Mutations in potassium voltage-gated channel subfamily Q member 4 (KCNQ4) are etiologically linked to a type of nonsyndromic hearing loss, deafness nonsyndromic autosomal dominant 2 (DFNA2). We performed whole-exome sequencing for 98 families with hearing loss and found mutations in KCNQ4 in five families. In this study, we characterized two novel mutations in KCNQ4: a missense mutation (c.796G>T; p.Asp266Tyr) and an in-frame deletion mutation (c.259_267del; p.Val87_Asn89del). p.Asp266Tyr located in the channel pore region resulted in early onset and moderate hearing loss, whereas p.Val87_Asn89del located in the N-terminal cytoplasmic region resulted in late onset and high frequency-specific hearing loss. When heterologously expressed in HEK 293 T cells, both mutant proteins did not show defects in protein trafficking to the plasma membrane or in interactions with wild-type (WT) KCNQ4 channels. Patch-clamp analysis demonstrated that both p.Asp266Tyr and p.Val87_Asn89del mutant channels lost conductance and were completely unresponsive to KCNQ activators, such as retigabine, zinc pyrithione, and ML213. Channels assembled from WT-p.Asp266Tyr concatemers, like those from WT-WT concatemers, exhibited conductance and responsiveness to KCNQ activators. However, channels assembled from WT-p.Val87_Asn89del concatemers showed impaired conductance, suggesting that p.Val87_Asn89del caused complete loss-of-function with a strong dominant-negative effect on functional WT channels. Therefore, the main pathological mechanism may be related to loss of K+ channel activity, not defects in trafficking.
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Uehara DT, Freitas ÉL, Alves LU, Mazzeu JF, Auricchio MT, Tabith A, Monteiro ML, Rosenberg C, Mingroni-Netto RC. A novel KCNQ4 mutation and a private IMMP2L-DOCK4 duplication segregating with nonsyndromic hearing loss in a Brazilian family. Hum Genome Var 2015; 2:15038. [PMID: 27081546 PMCID: PMC4785540 DOI: 10.1038/hgv.2015.38] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2015] [Revised: 08/17/2015] [Accepted: 08/24/2015] [Indexed: 02/07/2023] Open
Abstract
Here we describe a novel missense variant in the KCNQ4 gene and a private duplication at 7q31.1 partially involving two genes (IMMP2L and DOCK4). Both mutations segregated with nonsyndromic hearing loss in a family with three affected individuals. Initially, we identified the duplication in a screening of 132 unrelated cases of hearing loss with a multiplex ligation-dependent probe amplification panel of genes that are candidates to have a role in hearing, including IMMP2L. Mapping of the duplication by array-CGH revealed that the duplication also encompassed the 3′-end of DOCK4. Subsequently, whole-exome sequencing identified the breakpoint of the rearrangement, thereby confirming the existence of a fusion IMMP2L-DOCK4 gene. Transcription products of the fusion gene were identified, indicating that they escaped nonsense-mediated messenger RNA decay. A missense substitution (c.701A>T) in KCNQ4 (a gene at the DFNA2A locus) was also identified by whole-exome sequencing. Because the substitution is predicted to be probably damaging and KCNQ4 has been implicated in hearing loss, this mutation might explain the deafness in the affected individuals, although a hypothetical effect of the product of the fusion gene on hearing cannot be completely ruled out.
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Affiliation(s)
- Daniela T Uehara
- Department of Genetics and Evolutionary Biology, Biosciences Institute, University of São Paulo , São Paulo, Brazil
| | - Érika L Freitas
- Department of Genetics and Evolutionary Biology, Biosciences Institute, University of São Paulo , São Paulo, Brazil
| | - Leandro U Alves
- Department of Genetics and Evolutionary Biology, Biosciences Institute, University of São Paulo , São Paulo, Brazil
| | | | - Maria Tbm Auricchio
- Department of Genetics and Evolutionary Biology, Biosciences Institute, University of São Paulo , São Paulo, Brazil
| | - Alfredo Tabith
- DERDIC, Pontifical Catholic University of São Paulo , São Paulo, Brazil
| | - Mário Lr Monteiro
- Department of Ophthalmology and Otorhinolaryngology, Faculty of Medicine, University of São Paulo , São Paulo, Brazil
| | - Carla Rosenberg
- Department of Genetics and Evolutionary Biology, Biosciences Institute, University of São Paulo , São Paulo, Brazil
| | - Regina C Mingroni-Netto
- Department of Genetics and Evolutionary Biology, Biosciences Institute, University of São Paulo , São Paulo, Brazil
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Young JC. The role of the cytosolic HSP70 chaperone system in diseases caused by misfolding and aberrant trafficking of ion channels. Dis Model Mech 2015; 7:319-29. [PMID: 24609033 PMCID: PMC3944492 DOI: 10.1242/dmm.014001] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
Protein-folding diseases are an ongoing medical challenge. Many diseases within this group are genetically determined, and have no known cure. Among the examples in which the underlying cellular and molecular mechanisms are well understood are diseases driven by misfolding of transmembrane proteins that normally function as cell-surface ion channels. Wild-type forms are synthesized and integrated into the endoplasmic reticulum (ER) membrane system and, upon correct folding, are trafficked by the secretory pathway to the cell surface. Misfolded mutant forms traffic poorly, if at all, and are instead degraded by the ER-associated proteasomal degradation (ERAD) system. Molecular chaperones can assist the folding of the cytosolic domains of these transmembrane proteins; however, these chaperones are also involved in selecting misfolded forms for ERAD. Given this dual role of chaperones, diseases caused by the misfolding and aberrant trafficking of ion channels (referred to here as ion-channel-misfolding diseases) can be regarded as a consequence of insufficiency of the pro-folding chaperone activity and/or overefficiency of the chaperone ERAD role. An attractive idea is that manipulation of the chaperones might allow increased folding and trafficking of the mutant proteins, and thereby partial restoration of function. This Review outlines the roles of the cytosolic HSP70 chaperone system in the best-studied paradigms of ion-channel-misfolding disease--the CFTR chloride channel in cystic fibrosis and the hERG potassium channel in cardiac long QT syndrome type 2. In addition, other ion channels implicated in ion-channel-misfolding diseases are discussed.
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Affiliation(s)
- Jason C Young
- McGill University, Department of Biochemistry, Groupe de Recherche Axé sur la Structure des Protéines, 3649 Promenade Sir William Osler, Montreal, QC H3G 0B1, Canada
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Progress and prospects in human genetic research into age-related hearing impairment. BIOMED RESEARCH INTERNATIONAL 2014; 2014:390601. [PMID: 25140308 PMCID: PMC4130297 DOI: 10.1155/2014/390601] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 01/29/2014] [Accepted: 06/26/2014] [Indexed: 11/23/2022]
Abstract
Age-related hearing impairment (ARHI) is a complex, multifactorial disorder that is attributable to confounding intrinsic and extrinsic factors. The degree of impairment shows substantial variation between individuals, as is also observed in the senescence of other functions. This individual variation would seem to refute the stereotypical view that hearing deterioration with age is inevitable and may indicate that there is ample scope for preventive intervention. Genetic predisposition could account for a sizable proportion of interindividual variation. Over the past decade or so, tremendous progress has been made through research into the genetics of various forms of hearing impairment, including ARHI and our knowledge of the complex mechanisms of auditory function has increased substantially. Here, we give an overview of recent investigations aimed at identifying the genetic risk factors involved in ARHI and of what we currently know about its pathophysiology. This review is divided into the following sections: (i) genes causing monogenic hearing impairment with phenotypic similarities to ARHI; (ii) genes involved in oxidative stress, biologic stress responses, and mitochondrial dysfunction; and (iii) candidate genes for senescence, other geriatric diseases, and neurodegeneration. Progress and prospects in genetic research are discussed.
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Schmutz SM. An analysis of the inheritance pattern of an adult-onset hearing loss in Border Collie dogs. Canine Genet Epidemiol 2014; 1:6. [PMID: 26401323 PMCID: PMC4574391 DOI: 10.1186/2052-6687-1-6] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2014] [Accepted: 04/22/2014] [Indexed: 11/10/2022] Open
Abstract
Background During routine diagnostic BAER testing of dogs of various breeds for private owners at the Western College of Veterinary Medicine in Saskatoon, it became evident that some individual dogs developed hearing loss as adults. Although inherited congenital deafness has been widely reported in dogs, this type of deafness had not. Findings Special clinics were set up to screen working Border Collies at herding competitions. To determine the typical age that geriatric deafness might be expected, retired dogs were also recruited. Five of the 10 Border Collies 12 years of age or older had hearing loss (1 bilaterally deaf and 4 had reduced hearing). The adult onset deafness which exhibited in three families, did not usually occur until 5 years of age, too young to be geriatric deafness. This adult onset deafness fits an autosomal dominant pattern of inheritance. Several of these dogs had been BAER tested at younger ages with no sign of deafness. The deaf dogs were not associated with either gender. A survey was developed which was completed by the dog owners, that indicated that the hearing loss was gradual, not sudden. In addition, some family studies were conducted. Conclusions Dogs at 5 years of age were often in the prime of their herding careers and then did not respond appropriately to distant commands. This type of deafness is important to dog owners but is also a potential medical model for some forms of hearing loss in humans. This report also suggests that geriatric hearing loss is common in dogs older than 12 years. Electronic supplementary material The online version of this article (doi:10.1186/2052-6687-1-6) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Sheila M Schmutz
- Department of Animal and Poultry Science, University of Saskatchewan, Saskatoon, SK S7N 5A8 Canada
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Naito T, Nishio SY, Iwasa YI, Yano T, Kumakawa K, Abe S, Ishikawa K, Kojima H, Namba A, Oshikawa C, Usami SI. Comprehensive genetic screening of KCNQ4 in a large autosomal dominant nonsyndromic hearing loss cohort: genotype-phenotype correlations and a founder mutation. PLoS One 2013; 8:e63231. [PMID: 23717403 PMCID: PMC3662675 DOI: 10.1371/journal.pone.0063231] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2012] [Accepted: 04/02/2013] [Indexed: 11/28/2022] Open
Abstract
The present study of KCNQ4 mutations was carried out to 1) determine the prevalence by unbiased population-based genetic screening, 2) clarify the mutation spectrum and genotype/phenotype correlations, and 3) summarize clinical characteristics. In addition, a review of the reported mutations was performed for better understanding of this deafness gene. The screening using 287 probands from unbiased Japanese autosomal dominant nonsyndromic hearing loss (ADNSHL) families identified 19 families with 7 different disease causing mutations, indicating that the frequency is 6.62% (19/287). While the majority were private mutations, one particular recurrent mutation, c.211delC, was observed in 13 unrelated families. Haplotype analysis in the vicinity of c.211delC suggests existence of a common ancestor. The majority of the patients showed all frequency, but high-frequency predominant, sensorineural hearing loss. The present study adds a new typical audiogram configuration characterized by mid-frequency predominant hearing loss caused by the p.V230E mutation. A variant at the N-terminal site (c. 211delC) showed typical ski-slope type audiogram configuration. Concerning clinical features, onset age was from 3 to 40 years old, and mostly in the teens, and hearing loss was gradually progressive. Progressive nature is a common feature of patients with KCNQ4 mutations regardless of the mutation type. In conclusion, KCNQ4 mutations are frequent among ADNSHL patients, and therefore screening of the gene and molecular confirmation of these mutations have become important in the diagnosis of these conditions.
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Affiliation(s)
- Takehiko Naito
- Department of Otorhinolaryngology, Shinshu University School of Medicine, Matsumoto, Japan
| | - Shin-ya Nishio
- Department of Otorhinolaryngology, Shinshu University School of Medicine, Matsumoto, Japan
| | - Yoh-ichiro Iwasa
- Department of Otorhinolaryngology, Shinshu University School of Medicine, Matsumoto, Japan
| | - Takuya Yano
- Department of Otorhinolaryngology, Shinshu University School of Medicine, Matsumoto, Japan
| | - Kozo Kumakawa
- Department of Otolaryngology, Toranomon Hospital, Tokyo, Japan
| | - Satoko Abe
- Department of Otolaryngology, Toranomon Hospital, Tokyo, Japan
| | - Kotaro Ishikawa
- Department of Otorhinolaryngology, Jichi Medical University, Tochigi, Japan
| | - Hiromi Kojima
- Department of Otorhinolaryngology, Jikei University School of Medicine, Tokyo, Japan
| | - Atsushi Namba
- Department of Otorhinolaryngology, Hirosaki University School of Medicine, Hirosaki, Japan
| | - Chie Oshikawa
- Department of Otorhinolaryngology, Kyushu University School of Medicine, Fukuoka, Japan
| | - Shin-ichi Usami
- Department of Otorhinolaryngology, Shinshu University School of Medicine, Matsumoto, Japan
- * E-mail:
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