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Tsukada K, Nishio SY, Takumi Y, Usami SI. Comparison of vestibular function in hereditary hearing loss patients with GJB2, CDH23, and SLC26A4 variants. Sci Rep 2024; 14:10596. [PMID: 38720048 PMCID: PMC11078969 DOI: 10.1038/s41598-024-61442-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2023] [Accepted: 05/06/2024] [Indexed: 05/12/2024] Open
Abstract
To investigate the association between hereditary hearing loss and vestibular function, we compared vestibular function and symptoms among patients with GJB2, SLC26A4, and CDH23 variants. Thirty-nine patients with sensory neural hearing loss (11 males and 28 females) with biallelic pathogenic variants in either GJB2, SLC26A4, or CDH23 were included in this study (13 GJB2, 15 SLC26A4, and 11 CDH23). The patients were examined using caloric testing and cervical and ocular vestibular-evoked myogenic potentials (cVEMP and oVEMP). We also compared vestibular function and symptoms between patients with these gene variants and 78 normal-hearing ears without vestibular symptoms as controls. The frequency of semicircular canal hypofunction in caloric testing was higher in patients with SLC26A4 variants (47%) than in those with GJB2 (0%) and CDH23 variants (27%). According to the cVEMP results, 69% of patients with GJB2 variants had saccular hypofunction, a significantly higher proportion than in those carrying other variants (SLC26A4, 20%; CDH23, 18%). In oVEMP, which reflects utricular function, no difference was observed in the frequency of hypofunction among the three genes (GJB2, 15%; SLC26A4, 40%; and CDH23, 36%). Hence, discernable trends indicate vestibular dysfunction associated with each gene.
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Affiliation(s)
- Keita Tsukada
- Department of Otorhinolaryngology Head and Neck Surgery, Shinshu University School of Medicine, 3-1-1 Asahi, Matsumoto, 390-8621, Japan.
| | - Shin-Ya Nishio
- Department of Hearing Implant Sciences, Shinshu University School of Medicine, 3-1-1 Asahi, Matsumoto, 390-8621, Japan
| | - Yutaka Takumi
- Department of Otorhinolaryngology Head and Neck Surgery, Shinshu University School of Medicine, 3-1-1 Asahi, Matsumoto, 390-8621, Japan
| | - Shin-Ichi Usami
- Department of Hearing Implant Sciences, Shinshu University School of Medicine, 3-1-1 Asahi, Matsumoto, 390-8621, Japan
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2
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To-Mai XH, Nguyen HT, Nguyen-Thi TT, Nguyen TV, Nguyen-Thi MN, Thai KQ, Lai MT, Nguyen TA. Prevalence of common autosomal recessive mutation carriers in women in the Southern Vietnam following the application of expanded carrier screening. Sci Rep 2024; 14:7461. [PMID: 38553482 PMCID: PMC10980709 DOI: 10.1038/s41598-024-57513-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2023] [Accepted: 03/19/2024] [Indexed: 04/02/2024] Open
Abstract
The common autosomal recessive (AR) mutation carrier is still unknown in Vietnam. This study aims to identify the most common AR gene mutation carriers in women of reproductive age to build a Vietnamese-specific carrier screening panel for AR and X-linked disorders in the preconception and prenatal healthcare program. A cross-sectional study was conducted at University Medical Center-Branch 2 in Ho Chi Minh City from December 1st, 2020, to June 30th, 2023. 338 women have consented to take a 5 mL blood test to identify 540 recessive genes. The carrier screening panel was designed based on the American College of Medical Genetics and Genomics (ACMG)-recommended genes and suggestions from 104 clinical experts in Vietnam. Obstetricians and genetic experts counseled all positive testing results to discuss the possibility of recessive diseases in their offspring. The most common recessive disorders were defined at a prevalence of 1 in 60 or greater, and those were added to a Vietnamese-specific carrier screening panel. 338 non-pregnant and pregnant women underwent the expanded carrier screening (ECS). The carrier frequency was 63.6%, in which 215 women carried at least one AR gene mutation. GJB2 hearing impairment was identified as the most common chronic condition (1 in 5). The second most common AR disorder was beta-thalassemia (1 in 16), followed by cystic fibrosis (1 in 23), G6PD deficiency (1 in 28), Wilson's disease (1 in 31), Usher's syndrome (1 in 31), and glycogen storage disease (1 in 56). Seven common recessive genes were added in ethnic-based carrier screening. Women in the South of Vietnam have been carried for many recessive conditions at high frequency, such as hearing impairment, genetic anemia, and cystic fibrosis. It is necessary to implement a preconception and prenatal screening program by using seven widely popular AR genes in a Vietnamese-specific carrier screening panel to reduce the burden related to AR and X-linked disorders.
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Affiliation(s)
- Xuan-Hong To-Mai
- University of Alberta, Edmonton, Canada
- University of Nam Can Tho, Can Tho, Vietnam
| | - Huu-Trung Nguyen
- University of Medicine and Pharmacy at Ho Chi Minh City, Ho Chi Minh City, Vietnam
- University Medical Center-Branch 2, Ho Chi Minh City, Vietnam
| | | | - Thuy-Vy Nguyen
- University of Science, Vietnam National University Ho Chi Minh, Ho Chi Minh City, Vietnam
- Ktest Company, Ho Chi Minh City, Vietnam
| | - My-Nuong Nguyen-Thi
- University of Science, Vietnam National University Ho Chi Minh, Ho Chi Minh City, Vietnam
- Ktest Company, Ho Chi Minh City, Vietnam
| | | | | | - Tuan-Anh Nguyen
- University Medical Center-Branch 2, Ho Chi Minh City, Vietnam.
- Molecular Biomedical Center, University Medical Center, Ho Chí Minh City, Vietnam.
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3
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Sakata A, Kashio A, Koyama M, Urata S, Koyama H, Yamasoba T. Hearing and Hearing Loss Progression in Patients with GJB2 Gene Mutations: A Long-Term Follow-Up. Int J Mol Sci 2023; 24:16763. [PMID: 38069086 PMCID: PMC10705933 DOI: 10.3390/ijms242316763] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2023] [Revised: 11/19/2023] [Accepted: 11/23/2023] [Indexed: 12/18/2023] Open
Abstract
We aimed to investigate whether the degree of hearing loss with GJB2 mutations could be predicted by distinguishing between truncating and non-truncating mutations and whether the genotype could predict the hearing loss level. Additionally, we examined the progression of hearing loss in individuals monitored for over 2 years for an average of 6.9 years. The proportion of truncating mutations was higher in patients with profound and severe hearing loss, but it was not accurate enough to predict the degree of hearing loss. Via genotype analysis, mutations of the p.Arg143Trp variants were associated with profound hearing loss, while mutations of the p.Leu79Cysfs*3 allele exhibited a wide range of hearing loss, suggesting that specific genotypes can predict the hearing loss level. Notably, there were only three cases of progression in four ears, all of which involved the p.Leu79Cysfs*3 mutation. Over the long-term follow-up, 4000 Hz was significant, and there was a trend of progression at 250 Hz, suggesting that close monitoring at these frequencies during follow-up may be crucial to confirm progression. The progression of hearing loss was observed in moderate or severe hearing loss cases at the time of the initial diagnosis, emphasizing that children with this level of hearing loss need regular follow-ups.
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Affiliation(s)
- Aki Sakata
- Department of Otolaryngology and Head and Neck Surgery, Graduate School of Medicine, The University of Tokyo, Tokyo 113-8654, Japan; (A.S.); (A.K.); (M.K.); (S.U.); (H.K.)
| | - Akinori Kashio
- Department of Otolaryngology and Head and Neck Surgery, Graduate School of Medicine, The University of Tokyo, Tokyo 113-8654, Japan; (A.S.); (A.K.); (M.K.); (S.U.); (H.K.)
| | - Misaki Koyama
- Department of Otolaryngology and Head and Neck Surgery, Graduate School of Medicine, The University of Tokyo, Tokyo 113-8654, Japan; (A.S.); (A.K.); (M.K.); (S.U.); (H.K.)
| | - Shinji Urata
- Department of Otolaryngology and Head and Neck Surgery, Graduate School of Medicine, The University of Tokyo, Tokyo 113-8654, Japan; (A.S.); (A.K.); (M.K.); (S.U.); (H.K.)
| | - Hajime Koyama
- Department of Otolaryngology and Head and Neck Surgery, Graduate School of Medicine, The University of Tokyo, Tokyo 113-8654, Japan; (A.S.); (A.K.); (M.K.); (S.U.); (H.K.)
| | - Tatsuya Yamasoba
- Department of Otolaryngology and Head and Neck Surgery, Graduate School of Medicine, The University of Tokyo, Tokyo 113-8654, Japan; (A.S.); (A.K.); (M.K.); (S.U.); (H.K.)
- Tokyo Teishin Hospital, Tokyo 102-0071, Japan
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Yen TT, Chen IC, Cho S, Chang TG, Shih KH, Hua MW, Li JL, Hsu CY, Hsiao TH, Chen YM. GJB2 p.V37I Mutation Associated With Moderate Nonsyndromic Hearing Loss in an Adult Taiwanese Population. Ear Hear 2023; 44:1423-1429. [PMID: 37271870 DOI: 10.1097/aud.0000000000001384] [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: 06/06/2023]
Abstract
BACKGROUND Gap junction protein beta 2 ( GJB2 ) p.V37I mutations are the most important hereditary cause of sensorineural hearing loss (SNHL) in Taiwan. Hearing outcomes are associated with hearing levels at baseline and the duration of follow-up. However, the audiological features of GJB2 p.V37I mutations in the adult population are unknown. The objectives of the present study were to investigate the audiological features, progression rate, and allele frequency of GJB2 p.V37I mutations among an adult Taiwanese population. METHODS Subjects of this case-control study were chosen from 13,580 participants of the Taiwan Precision Medicine Initiative. The genetic variations of GJB2 p.V37I were determined by polymerase chain reaction. We analyzed existing pure-tone threshold data from 38 individuals who were homozygous or compound heterozygotes for GJB2 p.V37I, 129 who were heterozygotes, and 602 individuals who were wild-type. Phenome-wide association studies (PheWAS) analysis was also performed to identify phenotypes associated with GJB2 p.V37I. RESULTS The minor allele frequency of GJB2 p.V37I was 0.92% in our study population. The mean hearing level of participants with a p.V37I mutation indicated moderate to severe hearing loss with 38.2% ± 22.3% binaural hearing impairment. GJB2 p.V37I was associated with an increased risk of hearing disability (odds ratio: 21.46, 95% confidence interval: 8.62 to 53.44, p < 0.001) in an autosomal recessive pattern. In addition, PheWAS discovered a significant association between GJB2 p.V37I and fracture of the humerus. GJB2 p.V37I is a pathogenic and prevalent variant of SNHL among the adult population. CONCLUSIONS The present study recommends patients with known GJB2 p.V37I mutations receive regular audiometric evaluation and genetic counseling. Early assistive listening device intervention is suggested to improve the quality of hearing.
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Affiliation(s)
- Ting-Ting Yen
- Department of Otolaryngology, Taichung Veterans General Hospital, Taichung, Taiwan
- School of Medicine, College of Medicine, National Yang-Ming Chiao Tung University, Taipei, Taiwan
| | - I-Chieh Chen
- Department of Medical Research, Taichung Veterans General Hospital, Taichung, Taiwan
| | - Sudi Cho
- Department of Neurobiology, Physiology and Behavior, College of Biological Sciences, University of California, Davis, California, USA
| | - Ting-Gang Chang
- Department of Psychiatry, Taichung Veterans General Hospital, Taichung, Taiwan
- Department of Psychology, School of Psychology,Chung Shan Medical University, Taichung, Taiwan
- Department of Post-Baccalaureate Medicine, College of Medicine, National Chung Hsing University, Taichung, Taiwan
| | - Kai-Hsiang Shih
- Department of Otolaryngology, Taichung Veterans General Hospital, Taichung, Taiwan
| | - Men-Wei Hua
- Department of Otolaryngology, Taichung Veterans General Hospital, Taichung, Taiwan
| | - Jui-Lin Li
- Department of Otolaryngology, Taichung Veterans General Hospital, Taichung, Taiwan
| | - Chiann-Yi Hsu
- Department of Medical Research, Taichung Veterans General Hospital, Taichung, Taiwan
| | - Tzu-Hung Hsiao
- Department of Medical Research, Taichung Veterans General Hospital, Taichung, Taiwan
- Department of Public Health, College of Medicine, Fu Jen Catholic University, New Taipei City, Taiwan
- Institute of Genomics and Bioinformatics, College of Life Sciences, National Chung Hsing University, Taichung, Taiwan
| | - Yi-Ming Chen
- School of Medicine, College of Medicine, National Yang-Ming Chiao Tung University, Taipei, Taiwan
- Department of Medical Research, Taichung Veterans General Hospital, Taichung, Taiwan
- Division of Allergy, Immunology, and Rheumatology, Department of Internal Medicine, Taichung Veterans General Hospital, Taichung, Taiwan
- Department of Post-Baccalaureate Medicine, College of Medicine, National Chung Hsing University, Taichung, Taiwan
- Ph.D. Program in Translational Medicine and Rong Hsing Research Center for Translational Medicine, College of Life Sciences, National Chung Hsing University, Taiwan
- Precision Medicine Research Center, College of Medicine, College of Medicine, National Chung Hsing University, Taichung, Taiwan
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5
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Hu Y, Xia Z, Chen P. Follow-up of infants with mild-to-moderate sensorineural hearing loss over three years. Int J Pediatr Otorhinolaryngol 2023; 173:111697. [PMID: 37604100 DOI: 10.1016/j.ijporl.2023.111697] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/30/2023] [Revised: 08/06/2023] [Accepted: 08/09/2023] [Indexed: 08/23/2023]
Abstract
OBJECTIVE To observe and analyse the hearing outcome in infants with mild-to-moderate sensorineural hearing loss (SNHL) who failed universal newborn hearing screening (UNHS). METHODS This retrospective cohort analysis included infants with mild-to-moderate SNHL and with complete etiological diagnosis and followed up over three years. RESULTS Out of 96 infants with mild-to-moderate SNHL 72 were stable (75%). Only one case was normal (1.04%), ten cases were improved (10.42%), and 13 were deteriorated (13.54%). The pathogenic mutation of GJB2 was the most common cause (50/96, 52.08%), and most of them were homozygous or complex heterozygous mutations of p.V37I (44/50, 88%). There were 11 cases (11.49%) with large vestibular aqueduct syndrome (LVAS) and nine cases (9.38%) with perinatal risk factors. Infants with GJB2 pathogenic mutation and those without certain etiology mostly had unchanged hearing levels, accounting for 84% (42/50) and 84.61% (22/26), respectively. Hearing deterioration in LVAS was associated with seven cases (63.64%). There was no difference in types of outcomes in perinatal risk factor infants, who were more likely to improve than the other groups, but there were three cases (33.3%) deteriorated to profound hearing loss. Comparison of outcomes of different etiologies showed statistically significant difference (Chi-square = 28.673, p = 0.000). CONCLUSION Normal and improved hearing in infants with mild-to-moderate SNHL was rare before the age of three, unlike in many previous studies, and appropriate intervention is recommended. However, intervention should be adjusted according to the hearing outcomes because of the possibility of improvement or deterioration. The etiological diagnosis of infants with mild-to-moderate SNHL would be helpful for predicting the outcome and managing intervention.
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Affiliation(s)
- Yanling Hu
- Department of Otolaryngology, Wuhan Children's Hospital, Tongji Medical College, Huazhong University of Science & Technology, Wuhan, 430016, PR China
| | - Zhongfang Xia
- Department of Otolaryngology, Wuhan Children's Hospital, Tongji Medical College, Huazhong University of Science & Technology, Wuhan, 430016, PR China
| | - Ping Chen
- Department of Otolaryngology, Wuhan Children's Hospital, Tongji Medical College, Huazhong University of Science & Technology, Wuhan, 430016, PR China.
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6
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The Frequency of Common Deafness-Associated Variants Among 3,555,336 Newborns in China and 141,456 Individuals Across Seven Populations Worldwide. Ear Hear 2023; 44:232-241. [PMID: 36149380 DOI: 10.1097/aud.0000000000001274] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
OBJECTIVES Genetic screening can benefit early detection and intervention for hearing loss. The frequency of common deafness-associated variants in general populations is highly important for genetic screening and genetic counseling tailored to different ethnic backgrounds. We aimed to analyze the frequency of common deafness-associated variants in a large population-based Chinese newborn cohort and to explore the population-specific features in diverse populations worldwide. DESIGN This population-based cohort study analyzed the frequency of common deafness-associated variants in 3,555,336 newborns in the Chinese Newborn Concurrent Hearing and Genetic Screening cohort. Participants were newborn infants born between January 2007 and September 2020. Limited genetic screening for 20 variants in 4 common deafness-associated genes and newborn hearing screening were offered concurrently to all newborns in the Chinese Newborn Concurrent Hearing and Genetic Screening cohort. Sequence information of 141,456 individuals was also analyzed from seven ethnic populations from the Genome Aggregation Database for 20 common deafness-related variants. Statistical analysis was performed using R. RESULTS A total of 3,555,326 Chinese neonates completed the Newborn Concurrent Hearing and Genetic Screening were included for analysis. We reported the distinct landscape of common deafness-associated variants in this large population-based cohort. We found that the carrier frequencies of GJB2 , SLC26A4 , GJB3 , and MT-RNR were 2.53%, 2.05%, 0.37%, and 0.25%, respectively. Furthermore, GJB2 c.235delC was the most common variant with an allele frequency of 0.99% in the Chinese newborn population. We also demonstrated nine East-Asia-enriched variants, one Ashkenazi Jewish-enriched variant, and one European/American-enriched variant for hearing loss. CONCLUSIONS We showed the distinct landscape of common deafness-associated variants in the Chinese newborn population and provided insights into population-specific features in diverse populations. These data can serve as a powerful resource for otolaryngologists and clinical geneticists to inform population-adjusted genetic screening programs for hearing loss.
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7
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Jiang Y, Huang S, Zhang Y, Fang N, Liu Q, Liu Y, Bai L, Han D, Dai P. Evolutionary origin of pathogenic GJB2 alleles in China. Clin Genet 2022; 102:305-313. [PMID: 35841299 DOI: 10.1111/cge.14191] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2022] [Revised: 07/12/2022] [Accepted: 07/13/2022] [Indexed: 11/28/2022]
Abstract
The frequency of the pathogenic allele of the autosomal recessive deafness gene GJB2 varies among different populations in the world, and accumulates to a sufficiently high frequency in certain population. The purpose of this study is to investigate the origin and evolution of GJB2 pathogenic alleles in Chinese deaf patients. Children with non-syndromic hearing loss, and their parents, from 295 families were recruited. Customized capture probes targeted at 943 SNPs related to GJB2 gene were designed for sequencing of genomic DNA in blood samples. Haplotypes carrying pathogenic allele were analyzed through linkage disequilibrium block building, ancestry tracing, and extended haplotype heterozygosity calculation. Two pathogenic GJB2 alleles, c.235delC (18.41%) and c.109G>A (15.57%), were observed in 867 donors. For c.235delC allele, 3 different core haplotypes with one major haplotype (97.32%) were found, and their core SNPs were 100% conserved. For c.109G>A allele, 6 different haplotypes with one major haplotype (93.28%) were found and the major c.109G>A allele evolved from a specific ancestral haplotype. Geographical origins of donors carrying GJB2 c.109G>A and c.235delC core haplotypes centered between Qinghai and Neimenggu. GJB2 c.235delC has long-range linkage disequilibrium. No positive selection signature was found for GJB2 c.235delC or c.109G>A in the studied population. In conclusion, we discovered a single origin of GJB2 c.235delC allele and multiple independent origins of GJB2 c.109G>A allele. Alternative to positive selection or multiple independent recurrent mutation event, population bottleneck effect might account for the observed high population frequency of these pathogenic alleles.
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Affiliation(s)
- Yi Jiang
- Department of Otolaryngology-Head and Neck Surgery, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China.,Ear Institute, Shanghai Jiao Tong University School of Medicine, Shanghai, China.,Shanghai Key Laboratory of Translational Medicine on Ear and Nose Diseases, Shanghai, China
| | - Shasha Huang
- Department of Otolaryngology, Head and Neck Surgery, Institute of Otolaryngology, Chinese PLA General Hospital, Beijing, China.,National Clinical Research Center for Otolaryngologic Diseases, Beijing, China.,Key Lab of Hearing Impairment Science of Ministry of Education, Beijing, China.,Key Lab of Hearing Impairment Prevention and Treatment of Beijing, Beijing, China
| | - Yi Zhang
- Euler Technology, Beijing, China
| | - Nan Fang
- Beijing Scisoon Biotechnology Co., Ltd, Beijing, China
| | - Qian Liu
- Beijing Scisoon Biotechnology Co., Ltd, Beijing, China
| | - Yunchao Liu
- Beijing Scisoon Biotechnology Co., Ltd, Beijing, China
| | - Ling Bai
- Beijing Scisoon Biotechnology Co., Ltd, Beijing, China
| | - Dongyi Han
- Department of Otolaryngology, Head and Neck Surgery, Institute of Otolaryngology, Chinese PLA General Hospital, Beijing, China.,National Clinical Research Center for Otolaryngologic Diseases, Beijing, China.,Key Lab of Hearing Impairment Science of Ministry of Education, Beijing, China.,Key Lab of Hearing Impairment Prevention and Treatment of Beijing, Beijing, China
| | - Pu Dai
- Department of Otolaryngology, Head and Neck Surgery, Institute of Otolaryngology, Chinese PLA General Hospital, Beijing, China.,National Clinical Research Center for Otolaryngologic Diseases, Beijing, China.,Key Lab of Hearing Impairment Science of Ministry of Education, Beijing, China.,Key Lab of Hearing Impairment Prevention and Treatment of Beijing, Beijing, China
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8
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Zhu Y, Hu L, Yang L, Wang L, Lu Y, Dong X, Xiao T, Xu Z, Wu B, Zhou W. Association Between Expanded Genomic Sequencing Combined With Hearing Screening and Detection of Hearing Loss Among Newborns in a Neonatal Intensive Care Unit. JAMA Netw Open 2022; 5:e2220986. [PMID: 35816303 PMCID: PMC9274323 DOI: 10.1001/jamanetworkopen.2022.20986] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
IMPORTANCE Hearing loss is a global social burden. Early identification of hearing loss missed by newborn hearing screening tests in the neonatal intensive care unit is crucial. OBJECTIVE To assess the association between expanded genomic sequencing combined with hearing screening and detection of hearing loss as well as improvement in the neonatal intensive care unit. DESIGN, SETTING, AND PARTICIPANTS This cohort study was performed between August 8, 2016, and December 31, 2020, among 8078 newborns admitted to the neonatal intensive care unit of the Children's Hospital of Fudan University in Shanghai, China. Follow-up for hearing status was performed via telephone interviews between September 1 and November 30, 2021. EXPOSURES A hearing screening test and the expanded genomic sequencing targeting 2742 genes were administered to each patient. Those who failed the hearing screening test or had positive genetic findings were referred for diagnostic audiometry at a median of 3 months of age. MAIN OUTCOMES AND MEASURES The primary outcome was hearing loss missed by hearing screening test. Secondary outcomes were genetic findings and benefits associated with the expanded genomic sequencing for clinical management of patients in the neonatal intensive care unit. RESULTS Of 8078 patients (4666 boys [57.8%]; median age, 6.3 days [IQR, 3.0-12.0 days]), 52 of 240 (21.7%) received a diagnosis of hearing loss. Expanded genomic sequencing combined with hearing screening was associated with a 15.6% increase (7 of 45 patients) in cases of diagnosed hearing loss that were missed by hearing screening. Of the 52 patients with hearing loss, genetic factors were identified for 39 patients (75.0%); GJB2 and SLC26A4 were the most common genes identified. Patients with genetic findings experienced a more severe degree of hearing loss than those without genetic findings (21 profound, 4 severe, 7 moderate, and 7 mild vs 2 severe, 4 moderate, and 7 mild; P = .005), with more bilateral hearing loss (39 of 39 [100%] vs 9 of 13 [69.2%]; P = .003). Clinical management strategies were changed for patients who underwent genomic sequencing combined with hearing screening. CONCLUSIONS AND RELEVANCE This study suggests that expanded genomic sequencing combined with hearing screening may be effective at detecting hearing loss among patients in the neonatal intensive care unit.
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Affiliation(s)
- Yunqian Zhu
- Department of Neonatology, Children’s Hospital of Fudan University, National Children’s Medical Center, Shanghai, China
| | - Liyuan Hu
- Department of Neonatology, Children’s Hospital of Fudan University, National Children’s Medical Center, Shanghai, China
| | - Lin Yang
- Department of Pediatric Endocrinology and Inherited Metabolic Diseases, Children’s Hospital of Fudan University, National Children’s Medical Center, Shanghai, China
| | - Laishuan Wang
- Department of Neonatology, Children’s Hospital of Fudan University, National Children’s Medical Center, Shanghai, China
| | - Yulan Lu
- Center for Molecular Medicine, Children’s Hospital of Fudan University, National Children’s Medical Center, Shanghai, China
| | - Xinran Dong
- Center for Molecular Medicine, Children’s Hospital of Fudan University, National Children’s Medical Center, Shanghai, China
| | - Tiantian Xiao
- Department of Neonatology, Children’s Hospital of Fudan University, National Children’s Medical Center, Shanghai, China
| | - Zhengmin Xu
- Department of Otolaryngology–Head and Neck Surgery, Children’s Hospital of Fudan University, National Children’s Medical Center, Shanghai, China
| | - Bingbing Wu
- Center for Molecular Medicine, Children’s Hospital of Fudan University, National Children’s Medical Center, Shanghai, China
- Key Laboratory of Birth Defects, Children’s Hospital of Fudan University, National Children’s Medical Center, Shanghai, China
- Key Laboratory of Neonatal Diseases, Ministry of Health, Children’s Hospital of Fudan University, National Children’s Medical Center, Shanghai, China
| | - Wenhao Zhou
- Department of Neonatology, Children’s Hospital of Fudan University, National Children’s Medical Center, Shanghai, China
- Key Laboratory of Birth Defects, Children’s Hospital of Fudan University, National Children’s Medical Center, Shanghai, China
- Key Laboratory of Neonatal Diseases, Ministry of Health, Children’s Hospital of Fudan University, National Children’s Medical Center, Shanghai, China
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9
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Wang Z, Jiang M, Wu H, Li Y, Chen Y. A novel
MPZL2
c.
68delC
variant is associated with progressive hearing loss in Chinese population and literature review. Laryngoscope Investig Otolaryngol 2022; 7:870-876. [PMID: 35734045 PMCID: PMC9194966 DOI: 10.1002/lio2.829] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2022] [Revised: 04/05/2022] [Accepted: 05/11/2022] [Indexed: 11/08/2022] Open
Abstract
Objective Methods Results Conclusion
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Affiliation(s)
- Zhili Wang
- Department of Otolaryngology‐Head and Neck Surgery, Shanghai Ninth People's Hospital Shanghai Jiao Tong University School of Medicine Shanghai China
- Ear Institute Shanghai Jiao Tong University School of Medicine; Shanghai Key Laboratory of Translational Medicine on Ear and Nose Diseases (14DZ2260300) Shanghai China
| | - Mengda Jiang
- Department of Radiology, Shanghai Ninth People's Hospital Shanghai Jiao Tong University School of Medicine Shanghai China
| | - Hao Wu
- Department of Otolaryngology‐Head and Neck Surgery, Shanghai Ninth People's Hospital Shanghai Jiao Tong University School of Medicine Shanghai China
- Ear Institute Shanghai Jiao Tong University School of Medicine; Shanghai Key Laboratory of Translational Medicine on Ear and Nose Diseases (14DZ2260300) Shanghai China
| | - Yun Li
- Department of Otolaryngology‐Head and Neck Surgery, Shanghai Ninth People's Hospital Shanghai Jiao Tong University School of Medicine Shanghai China
- Ear Institute Shanghai Jiao Tong University School of Medicine; Shanghai Key Laboratory of Translational Medicine on Ear and Nose Diseases (14DZ2260300) Shanghai China
| | - Ying Chen
- Department of Otolaryngology‐Head and Neck Surgery, Shanghai Ninth People's Hospital Shanghai Jiao Tong University School of Medicine Shanghai China
- Ear Institute Shanghai Jiao Tong University School of Medicine; Shanghai Key Laboratory of Translational Medicine on Ear and Nose Diseases (14DZ2260300) Shanghai China
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10
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Phenotype-genotype correlation in patients with typical and atypical branchio-oto-renal syndrome. Sci Rep 2022; 12:969. [PMID: 35046468 PMCID: PMC8770796 DOI: 10.1038/s41598-022-04885-w] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2021] [Accepted: 12/29/2021] [Indexed: 12/31/2022] Open
Abstract
Some patients have an atypical form of branchio-oto-renal (BOR) syndrome, which does not satisfy the diagnostic criteria, despite carrying a pathogenic variant (P variant) or a likely pathogenic variant (LP variant) of a causative gene. P/LP variants phenotypic indices have yet to be determined in patients with typical and atypical BOR syndrome. We hypothesized that determining phenotypic and genetic differences between patients with typical and atypical BOR syndrome could inform such indices. Subjects were selected from among patients who underwent genetic testing to identify the cause of hearing loss. Patients were considered atypical when they had two major BOR diagnostic criteria, or two major criteria and one minor criterion; 22 typical and 16 atypical patients from 35 families were included. Genetic analysis of EYA1, SIX1, and SIX5 was conducted by direct sequencing and multiplex ligation-dependent probe amplification. EYA1 P/LP variants were detected in 25% and 86% of atypical and typical patients, respectively. Four EYA1 P/LP variants were novel. Branchial anomaly, inner ear anomaly, and mixed hearing loss were correlated with P/LP variants. Development of refined diagnostic criteria and phenotypic indices for atypical BOR syndrome will assist in effective detection of patients with P/LP variants among those with suspected BOR syndrome.
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Hosoya M, Fujioka M, Nara K, Morimoto N, Masuda S, Sugiuchi T, Katsunuma S, Takagi A, Morita N, Ogawa K, Kaga K, Matsunaga T. Investigation of the hearing levels of siblings affected by a single GJB2 variant: Possibility of genetic modifiers. Int J Pediatr Otorhinolaryngol 2021; 149:110840. [PMID: 34293626 DOI: 10.1016/j.ijporl.2021.110840] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/19/2021] [Revised: 05/25/2021] [Accepted: 07/11/2021] [Indexed: 11/25/2022]
Abstract
OBJECTIVE Variants in GJB2 can cause autosomal recessive deafness (DFNB1). There is evidence for genotype-phenotype correlations of GJB2 variants; however, several genotypes can cause varying levels of hearing loss likely attributable to differences in genetic or environmental background. As siblings share approximately 50% of their genetic background and usually have a common environmental background, analysis of phenotypes of siblings with a specific GJB2 variant may reveal factors relevant to phenotypic variation. There have been no previous analyses of differences in hearing among siblings carrying a single GJB2 genotype. Here, we investigated hearing differences between siblings with a single GJB2 variant, which can cause various levels of hearing loss. METHODS We examined hearing levels in 16 pairs of siblings homozygous for the c.235delC variant of GJB2. Differences in hearing acuity between sibling pairs were detected by auditory evaluation. RESULTS Average differences in acoustic threshold >30 dB were observed between five pairs of siblings, whereas the remaining 11 pairs had average threshold values within approximately 10 dB of one another. Hearing loss varied from moderate to profound. CONCLUSION Our results indicate that auditory acuity associated with homozygosity for GJB2 c.235delC can vary in degree; however, in approximately 70% of younger siblings, it was approximately the same as that in the first child, despite a diverse spectrum of hearing loss among different families. These results suggest that differences in genetic background may modify the phenotype associated with homozygous GJB2 c.235delC.
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Affiliation(s)
- Makoto Hosoya
- Department of Otorhinolaryngology, Head and Neck Surgery, School of Medicine, Keio University, 35 Shinanomachi, Shinjuku-ku, Tokyo, 160-8582, Japan
| | - Masato Fujioka
- Department of Otorhinolaryngology, Head and Neck Surgery, School of Medicine, Keio University, 35 Shinanomachi, Shinjuku-ku, Tokyo, 160-8582, Japan
| | - Kiyomitsu Nara
- Division of Hearing and Balance Research, National Institute of Sensory Organs, National Hospital Organization Tokyo Medical Center, 2-5-1 Higashigaoka, Meguro-ku, Tokyo, 152-8902, Japan
| | - Noriko Morimoto
- Department of Otorhinolaryngology, National Center for Child Health and Development, 2-10-1 Okura, Setagaya-ku, Tokyo, 157-8535, Japan
| | - Sawako Masuda
- Department of Otorhinolaryngology, National Hospital Organization Mie National Hospital, 357 Osato-Kubota, Tsu, Mie, 514-0125, Japan
| | - Tomoko Sugiuchi
- Department of Otorhinolaryngology, Kanto Rosai Hospital, 1-1 Kizukisumiyoshi-cho, Nakahara-ku, Kawasaki-shi, Kanagawa, 211-8510, Japan
| | - Sayaka Katsunuma
- Department of Otorhinolaryngology, Hyogo Prefectural Kobe Children's Hospital, 1-6-7 Minatojima-minamimachi, Chuo-ku, Kobe-shi, Hyogo, 650-0047, Japan
| | - Akira Takagi
- Department of Otorhinolaryngology, Shizuoka General Hospital, 4-27-1 Kita Ando Aoi-ku, Shizuoka-shi, Shizuoka, 420-8527, Japan
| | - Noriko Morita
- Department of Otorhinolaryngology, Teikyo University Hospital, 2-11-1 Kaga, Itabashi-Ku, Tokyo, 173-8606, Japan; Department of Otorhinolaryngology, Kobari General Hospital, 29-1 Yokouchi, Noda, Chiba, 278-8501, Japan
| | - Kaoru Ogawa
- Department of Otorhinolaryngology, Head and Neck Surgery, School of Medicine, Keio University, 35 Shinanomachi, Shinjuku-ku, Tokyo, 160-8582, Japan
| | - Kimitaka Kaga
- Division of Hearing and Balance Research, National Institute of Sensory Organs, National Hospital Organization Tokyo Medical Center, 2-5-1 Higashigaoka, Meguro-ku, Tokyo, 152-8902, Japan
| | - Tatsuo Matsunaga
- Division of Hearing and Balance Research, 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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Yoshimura H, Nishio S, Usami S. Milestones toward cochlear gene therapy for patients with hereditary hearing loss. Laryngoscope Investig Otolaryngol 2021; 6:958-967. [PMID: 34693000 PMCID: PMC8513455 DOI: 10.1002/lio2.633] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2021] [Revised: 06/30/2021] [Accepted: 07/28/2021] [Indexed: 02/05/2023] Open
Abstract
A number of genes are reportedly responsible for hereditary hearing loss, which accounts for over 50% of all congenital hearing loss cases. Recent advances in genetic testing have enabled the identification of pathogenic variants in many cases, and systems have been developed to provide personalized treatment based on etiology. Gene therapy is expected to become an unprecedented curative treatment. Several reports have demonstrated the successful use of cochlear gene therapy to restore auditory function in mouse models of genetic deafness; however, many hurdles remain to its clinical application in humans. Herein, we focus on the frequency of deafness genes in patients with congenital and late-onset progressive hearing loss and discuss the following points regarding which genes need to be targeted to efficiently proceed with clinical application: (a) which cells' genes are expressed within the cochlea, (b) whether gene transfer to the targeted cells is possible using vectors such as adeno-associated virus, (c) what phenotype of hearing loss in patients is exhibited, and (d) whether mouse models exist to verify the effectiveness of treatment. Moreover, at the start of clinical application, gene therapy in combination with cochlear implantation may be useful for cases of progressive hearing loss.
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Affiliation(s)
- Hidekane Yoshimura
- Department of OtorhinolaryngologyShinshu University School of MedicineMatsumotoNaganoJapan
| | - Shin‐Ya Nishio
- Department of Hearing Implant SciencesShinshu University School of MedicineMatsumotoNaganoJapan
| | - Shin‐Ichi Usami
- Department of Hearing Implant SciencesShinshu University School of MedicineMatsumotoNaganoJapan
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Usami SI, Nishio SY. The genetic etiology of hearing loss in Japan revealed by the social health insurance-based genetic testing of 10K patients. Hum Genet 2021; 141:665-681. [PMID: 34599366 PMCID: PMC9035015 DOI: 10.1007/s00439-021-02371-3] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2021] [Accepted: 09/14/2021] [Indexed: 11/28/2022]
Abstract
Etiological studies have shown genetic disorders to be a major cause of sensorineural hearing loss, but there are a limited number of comprehensive etiological reports based on genetic analysis. In the present study, the same platform using a diagnostic DNA panel carrying 63 deafness genes and the same filtering algorithm were applied to 10,047 samples obtained from social health insurance-based genetic testing of hearing loss. The most remarkable result obtained in this comprehensive study was that the data first clarified the genetic epidemiology from congenital/early-onset deafness to late-onset hearing loss. The overall diagnostic rate was 38.8%, with the rate differing for each age group; 48.6% for the congenital/early-onset group (~5y.o.), 33.5% for the juvenile/young adult-onset group, and 18.0% for the 40+ y.o. group. Interestingly, each group showed a different kind of causative gene. With regard to the mutational spectra, there are certain recurrent variants that may be due to founder effects or hot spots. A series of haplotype studies have shown many recurrent variants are due to founder effects, which is compatible with human migration. It should be noted that, regardless of differences in the mutational spectrum, the clinical characteristics caused by particular genes can be considered universal. This comprehensive review clarified the detailed clinical characteristics (onset age, severity, progressiveness, etc.) of hearing loss caused by each gene, and will provide useful information for future clinical application, including genetic counseling and selection of appropriate interventions.
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Affiliation(s)
- Shin-Ichi Usami
- Department of Hearing Implant Sciences, Shinshu University School of Medicine, 3-1-1 Asahi, Matsumoto, 390-8621, Japan.
| | - Shin-Ya Nishio
- Department of Hearing Implant Sciences, Shinshu University School of Medicine, 3-1-1 Asahi, Matsumoto, 390-8621, Japan
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The Effects of GJB2 or SLC26A4 Gene Mutations on Neural Response of the Electrically Stimulated Auditory Nerve in Children. Ear Hear 2021; 41:194-207. [PMID: 31124793 DOI: 10.1097/aud.0000000000000744] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVES This study aimed to (1) investigate the effect of GJB2 and SLC26A4 gene mutations on auditory nerve function in pediatric cochlear implant users and (2) compare their results with those measured in implanted children with idiopathic hearing loss. DESIGN Participants included 20 children with biallelic GJB2 mutations, 16 children with biallelic SLC26A4 mutations, and 19 children with idiopathic hearing loss. All subjects except for two in the SLC26A4 group had concurrent Mondini malformation and enlarged vestibular aqueduct. All subjects used Cochlear Nucleus devices in their test ears. For each subject, electrophysiological measures of the electrically evoked compound action potential (eCAP) were recorded using both anodic- and cathodic-leading biphasic pulses. Dependent variables (DVs) of interest included slope of eCAP input/output (I/O) function, the eCAP threshold, and eCAP amplitude measured at the maximum comfortable level (C level) of the anodic-leading stimulus (i.e., the anodic C level). Slopes of eCAP I/O functions were estimated using statistical modeling with a linear regression function. These DVs were measured at three electrode locations across the electrode array. Generalized linear mixed effect models were used to evaluate the effects of study group, stimulus polarity, and electrode location on each DV. RESULTS Steeper slopes of eCAP I/O function, lower eCAP thresholds, and larger eCAP amplitude at the anodic C level were measured for the anodic-leading stimulus compared with the cathodic-leading stimulus in all subject groups. Children with GJB2 mutations showed steeper slopes of eCAP I/O function and larger eCAP amplitudes at the anodic C level than children with SLC26A4 mutations and children with idiopathic hearing loss for both the anodic- and cathodic-leading stimuli. In addition, children with GJB2 mutations showed a smaller increase in eCAP amplitude when the stimulus changed from the cathodic-leading pulse to the anodic-leading pulse (i.e., smaller polarity effect) than children with idiopathic hearing loss. There was no statistically significant difference in slope of eCAP I/O function, eCAP amplitude at the anodic C level, or the size of polarity effect on all three DVs between children with SLC26A4 mutations and children with idiopathic hearing loss. These results suggested that better auditory nerve function was associated with GJB2 but not with SLC26A4 mutations when compared with idiopathic hearing loss. In addition, significant effects of electrode location were observed for slope of eCAP I/O function and the eCAP threshold. CONCLUSIONS GJB2 and SLC26A4 gene mutations did not alter polarity sensitivity of auditory nerve fibers to electrical stimulation. The anodic-leading stimulus was generally more effective in activating auditory nerve fibers than the cathodic-leading stimulus, despite the presence of GJB2 or SLC26A4 mutations. Patients with GJB2 mutations appeared to have better functional status of the auditory nerve than patients with SLC26A4 mutations who had concurrent Mondini malformation and enlarged vestibular aqueduct and patients with idiopathic hearing loss.
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Hosoya M, Fujioka M, Murayama AY, Ogawa K, Okano H, Ozawa H. Dynamic Spatiotemporal Expression Changes in Connexins of the Developing Primate's Cochlea. Genes (Basel) 2021; 12:genes12071082. [PMID: 34356098 PMCID: PMC8307058 DOI: 10.3390/genes12071082] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2021] [Revised: 07/14/2021] [Accepted: 07/15/2021] [Indexed: 01/03/2023] Open
Abstract
Connexins are gap junction components that are essential for acquiring normal hearing ability. Up to 50% of congenital, autosomal-recessive, non-syndromic deafness can be attributed to variants in GJB2, the gene that encodes connexin 26. Gene therapies modifying the expression of connexins are a feasible treatment option for some patients with genetic hearing losses. However, the expression patterns of these proteins in the human fetus are not fully understood due to ethical concerns. Recently, the common marmoset was used as a primate animal model for the human fetus. In this study, we examined the expression patterns of connexin 26 and connexin 30 in the developing cochlea of this primate. Primate-specific spatiotemporal expression changes were revealed, which suggest the existence of primate-specific control of connexin expression patterns and specific functions of these gap junction proteins. Moreover, our results indicate that treatments for connexin-related hearing loss established in rodent models may not be appropriate for human patients, underscoring the importance of testing these treatments in primate models before applying them in human clinical trials.
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Affiliation(s)
- Makoto Hosoya
- Department of Otorhinolaryngology, Head and Neck Surgery, Keio University School of Medicine, 35 Shinanomachi Shinjuku-ku, Tokyo 160-8582, Japan; (M.H.); (K.O.); (H.O.)
| | - Masato Fujioka
- Department of Otorhinolaryngology, Head and Neck Surgery, Keio University School of Medicine, 35 Shinanomachi Shinjuku-ku, Tokyo 160-8582, Japan; (M.H.); (K.O.); (H.O.)
- Correspondence: ; Tel.: +81-3-5363-3827
| | - Ayako Y. Murayama
- Department of Physiology, Keio University School of Medicine, 35 Shinanomachi Shinjuku-ku, Tokyo 160-8582, Japan; (A.Y.M.); (H.O.)
- Laboratory for Marmoset Neural Architecture, RIKEN Center for Brain Science, Wako 351-0198, Japan
| | - Kaoru Ogawa
- Department of Otorhinolaryngology, Head and Neck Surgery, Keio University School of Medicine, 35 Shinanomachi Shinjuku-ku, Tokyo 160-8582, Japan; (M.H.); (K.O.); (H.O.)
| | - Hideyuki Okano
- Department of Physiology, Keio University School of Medicine, 35 Shinanomachi Shinjuku-ku, Tokyo 160-8582, Japan; (A.Y.M.); (H.O.)
- Laboratory for Marmoset Neural Architecture, RIKEN Center for Brain Science, Wako 351-0198, Japan
| | - Hiroyuki Ozawa
- Department of Otorhinolaryngology, Head and Neck Surgery, Keio University School of Medicine, 35 Shinanomachi Shinjuku-ku, Tokyo 160-8582, Japan; (M.H.); (K.O.); (H.O.)
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16
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Zhang Q, Qin T, Hu W, Janjua MU, Jin P. Putative Digenic GJB2/MYO7A Inheritance of Hearing Loss Detected in a Patient with 48,XXYY Klinefelter Syndrome. Hum Hered 2021; 85:117-124. [PMID: 34192699 DOI: 10.1159/000516854] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2021] [Accepted: 04/01/2021] [Indexed: 11/19/2022] Open
Abstract
OBJECTIVES Nonsyndromic hearing loss (NSHL) is the most frequent type of hereditary hearing impairment. Here, we explored the underlying genetic cause of NSHL in a three-generation family using whole-exome sequencing. The proband had concomitant NSHL and rare 48,XXYY Klinefelter syndrome. MATERIAL AND METHODS Genomic DNA was extracted from the peripheral blood of the proband and their family members. Sanger sequencing and pedigree verification were performed on the pathogenic variants filtered by whole-exome sequencing. The function of the variants was analyzed using bioinformatics software. RESULTS The proband was digenic heterozygous for p.V37I in the GJB2 gene and p.L347I in the MYO7A gene. The proband's mother had normal hearing and did not have any variant. The proband's father and uncle both had NSHL and were compound for the GJB2 p.V37I and MYO7A p.L347I variants, thus indicating a possible GJB2/MYO7A digenic inheritance of NSHL. 48,XXYY Klinefelter syndrome was discovered in the proband after the karyotype analysis, while his parents both had normal karyotypes. CONCLUSIONS Our findings reported a putative GJB2/MYO7A digenic inheritance form of hearing loss, expanding the genotype and phenotype spectrum of NSHL. In addition, this is the first report of concomitant NSHL and 48,XXYY syndrome.
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Affiliation(s)
- Qin Zhang
- Department of Endocrinology, The Third Xiangya Hospital, Central South University, Changsha, China
| | - Tiantian Qin
- Department of Endocrinology, The Third Xiangya Hospital, Central South University, Changsha, China
| | - Wenmu Hu
- Department of Endocrinology, The Third Xiangya Hospital, Central South University, Changsha, China
| | - Muhammad Usman Janjua
- Department of Endocrinology, The Third Xiangya Hospital, Central South University, Changsha, China
| | - Ping Jin
- Department of Endocrinology, The Third Xiangya Hospital, Central South University, Changsha, China
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Fukunaga I, Oe Y, Danzaki K, Ohta S, Chen C, Shirai K, Kawano A, Ikeda K, Kamiya K. Modeling gap junction beta 2 gene-related deafness with human iPSC. Hum Mol Genet 2021; 30:1429-1442. [PMID: 33997905 DOI: 10.1093/hmg/ddab097] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2020] [Revised: 03/29/2021] [Accepted: 03/31/2021] [Indexed: 02/06/2023] Open
Abstract
There are >120 forms of non-syndromic deafness associated with identified genetic loci. In particular, mutation of the gap junction beta 2 gene (GJB2), which encodes connexin (CX)26 protein, is the most frequent cause of hereditary deafness worldwide. We previously described an induction method to develop functional CX26 gap junction-forming cells from mouse-induced pluripotent stem cells (iPSCs) and generated in vitro models for GJB2-related deafness. However, functional CX26 gap junction-forming cells derived from human iPSCs or embryonic stem cells (ESCs) have not yet been reported. In this study, we generated human iPSC-derived functional CX26 gap junction-forming cells (iCX26GJCs), which have the characteristics of cochlear supporting cells. These iCX26GJCs had gap junction plaque-like formations at cell-cell borders and co-expressed several markers that are expressed in cochlear supporting cells. Furthermore, we generated iCX26GJCs derived from iPSCs from two patients with the most common GJB2 mutation in Asia, and these cells reproduced the pathology of GJB2-related deafness. These in vitro models may be useful for establishing optimal therapies and drug screening for various mutations in GJB2-related deafness.
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Affiliation(s)
- Ichiro Fukunaga
- Department of Otorhinolaryngology, Juntendo University Faculty of Medicine, Tokyo 1138421, Japan
| | - Yoko Oe
- Department of Otorhinolaryngology, Juntendo University Faculty of Medicine, Tokyo 1138421, Japan
| | - Keiko Danzaki
- Department of Otorhinolaryngology, Juntendo University Faculty of Medicine, Tokyo 1138421, Japan
| | - Sayaka Ohta
- Department of Otorhinolaryngology, Juntendo University Faculty of Medicine, Tokyo 1138421, Japan
| | - Cheng Chen
- Department of Otorhinolaryngology, Juntendo University Faculty of Medicine, Tokyo 1138421, Japan
| | - Kyoko Shirai
- Department of Otolaryngology, Head and Neck Surgery, Tokyo Medical University, Tokyo 1600023, Japan
| | - Atsushi Kawano
- Department of Otolaryngology, Head and Neck Surgery, Tokyo Medical University, Tokyo 1600023, Japan
| | - Katsuhisa Ikeda
- Department of Otorhinolaryngology, Juntendo University Faculty of Medicine, Tokyo 1138421, Japan
| | - Kazusaku Kamiya
- Department of Otorhinolaryngology, Juntendo University Faculty of Medicine, Tokyo 1138421, Japan
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Xiao C, Liu S, Wang H, Ding Y, Chen Y, Liu H. Genetic etiology study of four Chinese families with two nonsyndromic deaf children in succession by targeted next-generation sequencing. Mol Genet Genomic Med 2021; 9:e1634. [PMID: 33638616 PMCID: PMC8123758 DOI: 10.1002/mgg3.1634] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2020] [Revised: 12/09/2020] [Accepted: 02/10/2021] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND Genetic components contribute significantly to the cause of hearing loss. Nonsyndromic hearing loss has been shown to have high genetic heterogeneity. For families who had given birth to two nonsyndromic deaf children in succession, it seems that their deafness was highly related to genetics. OBJECTIVES This study aimed to disclose the genetic causes of the subjects from the four Chinese families with two nonsyndromic deaf children in succession who failed to find the genetic etiology of the hearing loss by common deafness genetic screening (GJB2, GJB3, SLC26A4, and MT-RNR1, including 20 hot variants in 4 genes). METHODS Targeted next-generation sequencing (NGS) of 127 known deafness genes was performed in probands of four families, followed by a series of comprehensive analyses of all family members combined with a literature review of related genes. RESULTS We identified pathogenic variants in three families including c.919-2A>G/c.1985G>A in SLC26A4; c.109G>A (p.V37I) in GJB2; and m.7505T>C in MT-TS1. Sanger sequencing confirmed that these variants segregated with the hearing impairment of each family. We also identified c.331C>T/c.625-5C>T/c.5717G>A in CDH23; c.138T>C in POU3F4 in two families, in which the pathogenicity in clinical was likely pathogenic or unknown. CONCLUSIONS Using the NGS detection technology, we found the genetic etiology of the HL in part of deaf families. Our study provided a useful piece of information for the variant spectrum of hearing loss in Chinese families with two deaf children in succession.
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Affiliation(s)
- Caixia Xiao
- Tianjin Women and Children Healthcare CenterTianjinChina
| | - Shuang Liu
- Tianjin Women and Children Healthcare CenterTianjinChina
| | - Hongyue Wang
- Tianjin Women and Children Healthcare CenterTianjinChina
| | - Yibing Ding
- Tianjin Women and Children Healthcare CenterTianjinChina
| | - Yaqiu Chen
- Tianjin Women and Children Healthcare CenterTianjinChina
| | - Haiyan Liu
- Tianjin Women and Children Healthcare CenterTianjinChina
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Fukunaga I, Oe Y, Danzaki K, Ohta S, Chen C, Iizumi M, Shiga T, Matsuoka R, Anzai T, Hibiya-Motegi R, Tajima S, Ikeda K, Akamatsu W, Kamiya K. Generation of two iPSC lines from siblings of a homozygous patient with hearing loss and a heterozygous carrier with normal hearing carrying p.G45E/Y136X mutation in GJB2. Stem Cell Res 2021; 53:102290. [PMID: 33780732 DOI: 10.1016/j.scr.2021.102290] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/25/2021] [Accepted: 03/10/2021] [Indexed: 10/21/2022] Open
Abstract
The gap junction beta-2 (GJB2) gene is the most common genetic cause of hereditary deafness worldwide. Among them, the G45E/Y136X mutation in GJB2 is the third most prevalent in Japan. In this study, we generated two induced pluripotent stem cell (iPSC) lines from peripheral blood mononuclear cells (PBMCs) of siblings with moderate-to-severe hearing loss (patient) or normal hearing (genetic carrier) carrying a homozygous or heterozygous G45E/Y136X mutation in GJB2 gene, respectively. These iPSC lines showed the expression of pluripotency markers and could differentiate into three germ layers. These disease-specific iPSC lines will be a powerful tool for investigating the pathogenesis of GJB2-related deafness.
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Affiliation(s)
- Ichiro Fukunaga
- Department of Otorhinolaryngology, Juntendo University Faculty of Medicine, Tokyo, Japan
| | - Yoko Oe
- Department of Otorhinolaryngology, Juntendo University Faculty of Medicine, Tokyo, Japan
| | - Keiko Danzaki
- Department of Otorhinolaryngology, Juntendo University Faculty of Medicine, Tokyo, Japan
| | - Sayaka Ohta
- Department of Otorhinolaryngology, Juntendo University Faculty of Medicine, Tokyo, Japan
| | - Cheng Chen
- Department of Otorhinolaryngology, Juntendo University Faculty of Medicine, Tokyo, Japan
| | - Madoka Iizumi
- Department of Otorhinolaryngology, Juntendo University Faculty of Medicine, Tokyo, Japan
| | - Takahiro Shiga
- Center for Genomic and Regenerative Medicine, Juntendo University School of Medicine, Tokyo, Japan
| | - Rina Matsuoka
- Department of Otorhinolaryngology, Juntendo University Faculty of Medicine, Tokyo, Japan
| | - Takashi Anzai
- Department of Otorhinolaryngology, Juntendo University Faculty of Medicine, Tokyo, Japan
| | - Remi Hibiya-Motegi
- Department of Otorhinolaryngology, Juntendo University Faculty of Medicine, Tokyo, Japan
| | - Shori Tajima
- Department of Otorhinolaryngology, Juntendo University Faculty of Medicine, Tokyo, Japan
| | - Katsuhisa Ikeda
- Department of Otorhinolaryngology, Juntendo University Faculty of Medicine, Tokyo, Japan
| | - Wado Akamatsu
- Center for Genomic and Regenerative Medicine, Juntendo University School of Medicine, Tokyo, Japan
| | - Kazusaku Kamiya
- Department of Otorhinolaryngology, Juntendo University Faculty of Medicine, Tokyo, Japan.
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The Neural Bases of Tinnitus: Lessons from Deafness and Cochlear Implants. J Neurosci 2021; 40:7190-7202. [PMID: 32938634 DOI: 10.1523/jneurosci.1314-19.2020] [Citation(s) in RCA: 51] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2019] [Revised: 08/05/2020] [Accepted: 08/08/2020] [Indexed: 02/06/2023] Open
Abstract
Subjective tinnitus is the conscious perception of sound in the absence of any acoustic source. The literature suggests various tinnitus mechanisms, most of which invoke changes in spontaneous firing rates of central auditory neurons resulting from modification of neural gain. Here, we present an alternative model based on evidence that tinnitus is: (1) rare in people who are congenitally deaf, (2) common in people with acquired deafness, and (3) potentially suppressed by active cochlear implants used for hearing restoration. We propose that tinnitus can only develop after fast auditory fiber activity has stimulated the synapse formation between fast-spiking parvalbumin positive (PV+) interneurons and projecting neurons in the ascending auditory path and coactivated frontostriatal networks after hearing onset. Thereafter, fast auditory fiber activity promotes feedforward and feedback inhibition mediated by PV+ interneuron activity in auditory-specific circuits. This inhibitory network enables enhanced stimulus resolution, attention-driven contrast improvement, and augmentation of auditory responses in central auditory pathways (neural gain) after damage of slow auditory fibers. When fast auditory fiber activity is lost, tonic PV+ interneuron activity is diminished, resulting in the prolonged response latencies, sudden hyperexcitability, enhanced cortical synchrony, elevated spontaneous γ oscillations, and impaired attention/stress-control that have been described in previous tinnitus models. Moreover, because fast processing is gained through sensory experience, tinnitus would not exist in congenital deafness. Electrical cochlear stimulation may have the potential to reestablish tonic inhibitory networks and thus suppress tinnitus. The proposed framework unites many ideas of tinnitus pathophysiology and may catalyze cooperative efforts to develop tinnitus therapies.
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Natural Course of Residual Hearing with Reference to GJB2 and SLC26A4 Genotypes: Clinical Implications for Hearing Rehabilitation. Ear Hear 2021; 42:644-653. [PMID: 33928925 DOI: 10.1097/aud.0000000000000965] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
BACKGROUND Understanding the characteristics of residual hearing at low frequencies and its natural course in relation to molecular genetic etiology may be important in developing rehabilitation strategies. Thus, we aimed to explore the characteristics and natural course of residual hearing at low frequencies associated with the two most frequent deafness genes: GJB2 and SLC26A4. METHODS Initially, 53 GJB2 and 65 SLC26A4 subjects were enrolled, respectively. Only those whose audiograms exhibited hearing thresholds ≤70 dB at 250 and 500 Hz, and who had at least 1-year follow-up period between the first and last audiograms, were included. Collectively, the clinical characteristics of 14 ears from eight subjects with GJB2 variants, and 31 ears from 22 subjects with SLC26A4 variants fulfilled the strict criteria. In this study, a dropout rate refers to an incidence of dropping out of the cohort by cochlear implant surgery due to severe hearing deterioration. RESULTS Among the ears with complete serial audiogram data set, significant residual hearing at low frequencies at the time of inclusion was observed in 18.8% of those with GJB2 variants (15 out of 80 ears) and 42.6% of those with SLC26A4 variants (46 out of 108 ears), revealing a difference between two deafness genes. Subsequently, ears with SLC26A4 variants (11 of 46 ears, 23.9%) turned out to have a higher dropout rate for cochlear implantation due to hearing deterioration within the first year than those with GJB2 variants (1 of 15, 6.7%), albeit with no statistical significance. Throughout the follow-up period (mean: 37.2 ± 6.8, range: 12 to 80 months), deterioration of residual hearing at low frequencies at 250 Hz (dB HL/y) and 500 Hz (dB HL/y) of those with GJB2 variants exhibited 3.1 ± 1.3 (range: 0 to 15) and 5.2 ± 1.6 (range: 0 to 20), respectively, suggesting the deterioration of residual hearing in GJB2 variants was rather slow and gradual. Specifically, GJB2 p.Leu79Cysfs*3 show less remarkable residual hearing at low frequencies, but then a relatively stable nature. In contrast, SLC26A4 variants demonstrated a significantly higher dropout rate due to severe hearing deterioration requiring cochlear implantation compared with the GJB2 variants. This trend was observed not only in the first-year follow-up period but also in the follow-up periods thereafter. The p.His723Arg;c.919-2A>G genotype of SLC26A4, in particular, was associated with a high propensity for sudden hearing deterioration, as indicated by the dropout rate, which was as high as 46.2% for cochlear implantation due to hearing deterioration during the first year follow-up period. Furthermore, the dropout rate for cochlear implantation was observed in 7.1% of those with GJB2 variants (one out of 14 ears) and 30.3% of those with SLC26A4 variants (10 out of 33 ears) throughout the entire follow-up period. CONCLUSIONS Our results suggest that there is a difference with respect to the progressive nature of residual hearing at low frequencies between the two most common genes responsible for hearing loss, which may provide clinical implications of having individualized rehabilitation and timely intervention.
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High Rates of Three Common GJB2 Mutations c.516G>C, c.-23+1G>A, c.235delC in Deaf Patients from Southern Siberia Are Due to the Founder Effect. Genes (Basel) 2020; 11:genes11070833. [PMID: 32708339 PMCID: PMC7397271 DOI: 10.3390/genes11070833] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2020] [Revised: 07/10/2020] [Accepted: 07/17/2020] [Indexed: 11/17/2022] Open
Abstract
The mutations in the GJB2 gene (13q12.11, MIM 121011) encoding transmembrane protein connexin 26 (Cx26) account for a significant portion of hereditary hearing loss worldwide. Earlier we found a high prevalence of recessive GJB2 mutations c.516G>C, c.-23+1G>A, c.235delC in indigenous Turkic-speaking Siberian peoples (Tuvinians and Altaians) from the Tyva Republic and Altai Republic (Southern Siberia, Russia) and proposed the founder effect as a cause for their high rates in these populations. To reconstruct the haplotypes associated with each of these mutations, the genotyping of polymorphic genetic markers both within and flanking the GJB2 gene was performed in 28 unrelated individuals homozygous for c.516G>C (n = 18), c.-23+1G>A (n = 6), or c.235delC (n = 4) as well as in the ethnically matched controls (62 Tuvinians and 55 Altaians) without these mutations. The common haplotypes specific for mutations c.516G>C, c.-23+1G>A, or c.235delC were revealed implying a single origin of each of these mutations. The age of mutations estimated by the DMLE+ v2.3 software and the single marker method is discussed in relation to ethnic history of Tuvinians and Altaians. The data obtained in this study support a crucial role of the founder effect in the high prevalence of GJB2 mutations c.516G>C, c.-23+1G>A, c.235delC in indigenous populations of Southern Siberia.
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Eshraghi AA, Polineni SP, Davies C, Shahal D, Mittal J, Al-Zaghal Z, Sinha R, Jindal U, Mittal R. Genotype-Phenotype Correlation for Predicting Cochlear Implant Outcome: Current Challenges and Opportunities. Front Genet 2020; 11:678. [PMID: 32765579 PMCID: PMC7381205 DOI: 10.3389/fgene.2020.00678] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2020] [Accepted: 06/02/2020] [Indexed: 12/13/2022] Open
Abstract
The use and utility of cochlear implantation has rapidly increased in recent years as technological advances in the field have expanded both the efficacy and eligible patient population for implantation. This review aims to serve as a general overview of the most common hearing disorders that have favorable auditory outcomes with cochlear implants (CI). Hearing loss in children caused by congenital cytomegalovirus infection, syndromic conditions including Pendred Syndrome, and non-syndromic genetic conditions such as hearing impairment associated with GJB2 mutations have shown to be successfully managed by CI. Furthermore, cochlear implantation provides the auditory rehabilitation for the most common etiology of hearing loss in adults and age-related hearing loss (ARHL) or presbycusis. However, in some cases, cochlear implantation have been associated with some challenges. Regarding implantation in children, studies have shown that sometimes parents seem to have unrealistic expectations regarding the ability of CI to provide auditory rehabilitation and speech improvement. Given the evidence revealing the beneficial effects of early intervention via CI in individuals with hearing disorders especially hearing loss due to genetic etiology, early auditory and genetic screening efforts may yield better clinical outcomes. There is a need to better understand genotype-phenotype correlations and CI outcome, so that effective genetic counseling and successful treatment strategies can be developed at the appropriate time for hearing impaired individuals.
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Affiliation(s)
- Adrien A. Eshraghi
- Department of Otolaryngology, Miller School of Medicine, University of Miami Hearing Research Laboratory, Miami, FL, United States
- Department of Neurological Surgery, Miller School of Medicine, Miami, FL, United States
- Department of Biomedical Engineering, University of Miami, Coral Gables, FL, United States
| | - Sai P. Polineni
- Department of Otolaryngology, Miller School of Medicine, University of Miami Hearing Research Laboratory, Miami, FL, United States
| | - Camron Davies
- Department of Otolaryngology, Miller School of Medicine, University of Miami Hearing Research Laboratory, Miami, FL, United States
| | - David Shahal
- Department of Otolaryngology, Miller School of Medicine, University of Miami Hearing Research Laboratory, Miami, FL, United States
| | - Jeenu Mittal
- Department of Otolaryngology, Miller School of Medicine, University of Miami Hearing Research Laboratory, Miami, FL, United States
| | - Zaid Al-Zaghal
- Department of Otolaryngology, Miller School of Medicine, University of Miami Hearing Research Laboratory, Miami, FL, United States
| | - Rahul Sinha
- Department of Otolaryngology, Miller School of Medicine, University of Miami Hearing Research Laboratory, Miami, FL, United States
| | - Urmi Jindal
- Department of Otolaryngology, Miller School of Medicine, University of Miami Hearing Research Laboratory, Miami, FL, United States
| | - Rahul Mittal
- Department of Otolaryngology, Miller School of Medicine, University of Miami Hearing Research Laboratory, Miami, FL, United States
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Lee SY, Shim YJ, Han JH, Song JJ, Koo JW, Oh SH, Lee S, Oh DY, Choi BY. The molecular etiology of deafness and auditory performance in the postlingually deafened cochlear implantees. Sci Rep 2020; 10:5768. [PMID: 32238869 PMCID: PMC7113281 DOI: 10.1038/s41598-020-62647-y] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2019] [Accepted: 03/02/2020] [Indexed: 11/09/2022] Open
Abstract
Recent advances in molecular genetic testing (MGT) have improved identification of genetic aetiology of candidates for cochlear implantation (CI). However, whether genetic information increases CI outcome predictability in post-lingual deafness remains unclear. Therefore, we evaluated the outcomes of CI with respect to genetic aetiology and clinical predictors by comparing the data of study subjects; those with an identified genetic aetiology (GD group), and those without identifiable variants (GUD group). First, we identified the genetic aetiology in 21 of 40 subjects and also observed genetic etiologic heterogeneity. The GD group demonstrated significantly greater improvement in speech perception scores over a 1-year period than did the GUD group. Further, inverse correlation between deafness duration and the 1-year improvement in speech perception scores was tighter in the GD group than in the GUD group. The weak correlation between deafness duration and CI outcomes in the GUD group might suggest the pathophysiology underlying GUD already significantly involves the cortex, leading to lesser sensitivity to further cortex issues such as deafness duration. Under our MGT protocol, the correlation between deafness duration and CI outcomes were found to rely on the presence of identifiable genetic aetiology, strongly advocating early CI in individual with proven genetic aetiologies.
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Affiliation(s)
- Sang-Yeon Lee
- Department of Otorhinolaryngology-Head and Neck Surgery, Seoul National University Bundang Hospital, Seongnam, South Korea
| | - Ye Ji Shim
- Department of Otorhinolaryngology-Head and Neck Surgery, Healthcare System Gangnam Center, Seoul National University Hospital, Seoul, South Korea
| | - Jin-Hee Han
- Department of Otorhinolaryngology-Head and Neck Surgery, Seoul National University Bundang Hospital, Seongnam, South Korea
| | - Jae-Jin Song
- Department of Otorhinolaryngology-Head and Neck Surgery, Seoul National University Bundang Hospital, Seongnam, South Korea
| | - Ja-Won Koo
- Department of Otorhinolaryngology-Head and Neck Surgery, Seoul National University Bundang Hospital, Seongnam, South Korea
| | - Seung Ha Oh
- Department of Otorhinolaryngology-Head and Neck Surgery, Seoul National University Hospital, Seoul, South Korea
| | - Seungmin Lee
- Department of Otorhinolaryngology-Head and Neck Surgery, Seoul National University Bundang Hospital, Seongnam, South Korea
| | - Doo-Yi Oh
- Department of Otorhinolaryngology-Head and Neck Surgery, Seoul National University Bundang Hospital, Seongnam, South Korea
| | - Byung Yoon Choi
- Department of Otorhinolaryngology-Head and Neck Surgery, Seoul National University Bundang Hospital, Seongnam, South Korea.
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Haplotype Analysis of GJB2 Mutations: Founder Effect or Mutational Hot Spot? Genes (Basel) 2020; 11:genes11030250. [PMID: 32120898 PMCID: PMC7140863 DOI: 10.3390/genes11030250] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2020] [Revised: 02/25/2020] [Accepted: 02/25/2020] [Indexed: 01/29/2023] Open
Abstract
The GJB2 gene is the most frequent cause of congenital or early onset hearing loss worldwide. In this study, we investigated the haplotypes of six GJB2 mutations frequently observed in Japanese hearing loss patients (i.e., c.235delC, p.V37I, p.[G45E; Y136X], p.R143W, c.176_191del, and c.299_300delAT) and analyzed whether the recurring mechanisms for each mutation are due to founder effects or mutational hot spots. Furthermore, regarding the mutations considered to be caused by founder effects, we also calculated the age at which each mutation occurred using the principle of genetic clock analysis. As a result, all six mutations were observed in a specific haplotype and were estimated to derive from founder effects. Our haplotype data together with their distribution patterns indicated that p.R143W and p.V37I may have occurred as multiple events, and suggested that both a founder effect and hot spot may be involved in some mutations. With regard to the founders' age of frequent GJB2 mutations, each mutation may have occurred at a different time, with the oldest, p.V37I, considered to have occurred around 14,500 years ago, and the most recent, c.176_191del, considered to have occurred around 4000 years ago.
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Prelingual Sensorineural Hearing Loss Caused by a Novel GJB2 Dominant Mutation in a Chinese Family. BIOMED RESEARCH INTERNATIONAL 2020; 2020:6370386. [PMID: 32090102 PMCID: PMC6996670 DOI: 10.1155/2020/6370386] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/23/2019] [Revised: 12/19/2019] [Accepted: 12/30/2019] [Indexed: 11/17/2022]
Abstract
Background GJB2 mutation is the most common cause of genetic deafness. Many pathogenic variations have already been identified, and thus, fewer and fewer novel pathogenic variations remain to be identified. Here, we describe a novel pathogenic variation associated with dominant hereditary deafness in a Chinese family. Methods In this study, we examined four generations of a Chinese family (M127) with hearing loss. Temporal CT scan, complete physical examination (including skin and hair), and audiological tests were performed. Targeted next-generation and Sanger sequencing were used to identify pathogenic mutations in affected individuals. Results All patients exhibited prelingual nonsyndromic sensorineural hearing loss, with severity ranging from moderate to severe. A novel dominant pathogenic variant c.205T > C (p.Phe69Leu) was identified in all patients in this family. Conclusions c.205T > C (p.Phe69Leu) was identified as a novel dominant pathogenic variant of GJB2 associated with prelingual nonsyndromic sensorineural hearing loss.GJB2 mutation is the most common cause of genetic deafness. Many pathogenic variations have already been identified, and thus, fewer and fewer novel pathogenic variations remain to be identified. Here, we describe a novel pathogenic variation associated with dominant hereditary deafness in a Chinese family.
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Usami SI, Nishio SY, Moteki H, Miyagawa M, Yoshimura H. Cochlear Implantation From the Perspective of Genetic Background. Anat Rec (Hoboken) 2020; 303:563-593. [PMID: 32027099 PMCID: PMC7064903 DOI: 10.1002/ar.24360] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2019] [Accepted: 12/13/2019] [Indexed: 12/18/2022]
Abstract
While cochlear implantation (CI) technology has greatly improved over the past 40 years, one aspect of CI that continues to pose difficulties is the variability of outcomes due to numerous factors involved in postimplantation performance. The electric acoustic stimulation (EAS) system has expanded indications for CI to include patients with residual hearing, and is currently becoming a standard therapy for these patients. Genetic disorders are known to be the most common cause of congenital/early-onset sensorineural hearing loss, and are also involved in a considerable proportion of cases of late-onset hearing loss. There has been a great deal of progress in the identification of deafness genes over the last two decades. Currently, more than 100 genes have been reported to be associated with non-syndromic hearing loss. Patients possessing a variety of deafness gene mutations have achieved satisfactory auditory performance after CI/EAS, suggesting that identification of the genetic background facilitates prediction of post-CI/EAS performance. When the intra-cochlear etiology is associated with a specific genetic background, there is a potential for good CI performance. Thus, it is essential to determine which region of the cochlea is affected by identifying the responsible genes. This review summarizes the genetic background of the patients receiving CI/EAS, and introduces detailed clinical data and CI/EAS outcomes in representative examples. Anat Rec, 303:563-593, 2020. © 2020 The Authors. The Anatomical Record published by Wiley Periodicals, Inc. on behalf of American Association of Anatomists.
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Affiliation(s)
- Shin-Ichi Usami
- Department of Otorhinolaryngology, Shinshu University School of Medicine, Matsumoto, Japan.,Department of Hearing Implant Sciences, Shinshu University School of Medicine, Matsumoto, Japan
| | - Shin-Ya Nishio
- Department of Otorhinolaryngology, Shinshu University School of Medicine, Matsumoto, Japan.,Department of Hearing Implant Sciences, Shinshu University School of Medicine, Matsumoto, Japan
| | - Hideaki Moteki
- Department of Otorhinolaryngology, Shinshu University School of Medicine, Matsumoto, Japan
| | - Maiko Miyagawa
- Department of Otorhinolaryngology, Shinshu University School of Medicine, Matsumoto, Japan
| | - Hidekane Yoshimura
- Department of Otorhinolaryngology, Shinshu University School of Medicine, Matsumoto, Japan.,Department of Hearing Implant Sciences, Shinshu University School of Medicine, Matsumoto, Japan
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Wu CC, Tsai CY, Lin YH, Chen PY, Lin PH, Cheng YF, Wu CM, Lin YH, Lee CY, Erdenechuluun J, Liu TC, Chen PL, Hsu CJ. Genetic Epidemiology and Clinical Features of Hereditary Hearing Impairment in the Taiwanese Population. Genes (Basel) 2019; 10:genes10100772. [PMID: 31581539 PMCID: PMC6826657 DOI: 10.3390/genes10100772] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2019] [Revised: 09/19/2019] [Accepted: 09/27/2019] [Indexed: 12/11/2022] Open
Abstract
Hereditary hearing impairment (HHI) is a common but heterogeneous clinical entity caused by mutations in a plethora of deafness genes. Research over the past few decades has shown that the genetic epidemiology of HHI varies significantly across populations. In this study, we used different genetic examination strategies to address the genetic causes of HHI in a large Taiwanese cohort composed of >5000 hearing-impaired families. We also analyzed the clinical features associated with specific genetic mutations. Our results demonstrated that next-generation sequencing-based examination strategies could achieve genetic diagnosis in approximately half of the families. Common deafness-associated genes in the Taiwanese patients assessed, in the order of prevalence, included GJB2, SLC26A4, OTOF, MYO15A, and MTRNR1, which were similar to those found in other populations. However, the Taiwanese patients had some unique mutations in these genes. These findings may have important clinical implications for refining molecular diagnostics, facilitating genetic counseling, and enabling precision medicine for the management of HHI.
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Affiliation(s)
- Chen-Chi Wu
- Department of Otolaryngology, National Taiwan University Hospital, Taipei 10002, Taiwan.
| | - Cheng-Yu Tsai
- Department of Otolaryngology, National Taiwan University Hospital, Taipei 10002, Taiwan.
- Graduate Institute of Medical Genomics and Proteomics, National Taiwan University College of Medicine, Taipei 10055, Taiwan.
| | - Yi-Hsin Lin
- Department of Otolaryngology, National Taiwan University Hospital, Taipei 10002, Taiwan.
| | - Pey-Yu Chen
- Department of Otolaryngology, Mackay Memorial Hospital, Taipei 10449, Taiwan.
| | - Pei-Hsuan Lin
- Department of Otolaryngology, National Taiwan University Hospital Yunlin Branch, Yunlin 64041, Taiwan.
| | - Yen-Fu Cheng
- Department of Medical Research, Taipei Veterans General Hospital, Taipei 11217, Taiwan.
- Department of Otolaryngology-Head and Neck Surgery, Taipei Veterans General Hospital, Taipei 11217, Taiwan.
| | - Che-Ming Wu
- Department of Otolaryngology-Head and Neck Surgery, Chang Gung Memorial Hospital, Chang Gung University, Linkou 33302, Taiwan.
| | - Yin-Hung Lin
- Graduate Institute of Medical Genomics and Proteomics, National Taiwan University College of Medicine, Taipei 10055, Taiwan.
| | - Chee-Yee Lee
- Department of Otolaryngology, Buddhist Tzuchi General Hospital, Taichung Branch, Taichung 42743, Taiwan.
| | - Jargalkhuu Erdenechuluun
- Department of Otolaryngology, Mongolian National University of Medical Sciences, Ulaanbaatar 14210, Mongolia.
- The EMJJ Otolaryngology Hospital, Ulaanbaatar 14210, Mongolia.
- Department of Otolaryngology, National Center for Maternal and Child Health, Ulaanbaatar 16060, Mongolia.
| | - Tien-Chen Liu
- Department of Otolaryngology, National Taiwan University Hospital, Taipei 10002, Taiwan.
| | - Pei-Lung Chen
- Graduate Institute of Medical Genomics and Proteomics, National Taiwan University College of Medicine, Taipei 10055, Taiwan.
- Department of Medical Genetics, National Taiwan University Hospital, Taipei 10041, Taiwan.
| | - Chuan-Jen Hsu
- Department of Otolaryngology, National Taiwan University Hospital, Taipei 10002, Taiwan.
- Department of Otolaryngology, Buddhist Tzuchi General Hospital, Taichung Branch, Taichung 42743, Taiwan.
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Clinical characteristics with long-term follow-up of four Okinawan families with moderate hearing loss caused by an OTOG variant. Hum Genome Var 2019; 6:37. [PMID: 31645975 PMCID: PMC6804730 DOI: 10.1038/s41439-019-0068-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2019] [Revised: 06/28/2019] [Accepted: 07/01/2019] [Indexed: 11/29/2022] Open
Abstract
We describe the clinical features of four Japanese families with moderate sensorineural hearing loss due to the OTOG gene variant. We analyzed 98 hearing loss-related genes in patients with hearing loss originally from the Okinawa Islands using next-generation sequencing. We identified a homozygous variant of the gene encoding otogelin NM_001277269(OTOG): c.330C>G, p.Tyr110* in four families. All patients had moderate hearing loss with a slightly downsloping audiogram, including low frequency hearing loss without equilibrium dysfunction. Progressive hearing loss was not observed over the long-term in any patient. Among the three patients who underwent newborn hearing screening, two patients passed the test. OTOG-associated hearing loss was considered to progress early after birth, leading to moderate hearing loss and the later stable phase of hearing loss. Therefore, there are patients whose hearing loss cannot be detected by NHS, making genetic diagnosis of OTOG variants highly useful for complementing NHS in the clinical setting. Based on the allele frequency results, hearing loss caused by the p.Tyr110* variant in OTOG might be more common than we identified. The p.Tyr110* variant was reported in South Korea, suggesting that this variant is a common cause of moderate hearing loss in Japanese and Korean populations. People born with mutations in a gene linked to moderate hearing loss don’t always show problems during newborn hearing screening and may benefit from genetic screening. Testing for this gene, OTOG, which encodes a protein expressed in sensory cells of the inner ear, could thus be an important complement to newborn hearing screening for individuals with a family history of hearing loss who may benefit from early medical intervention. A Japan-based team led by Akira Ganaha from the University of Miyazaki studied seven patients with hearing loss from four unrelated families living on the Japanese archipelago of Okinawa. Each had two copies of a recessive mutation in OTOG, a variant previously documented only in South Korea. Of the three who underwent newborn hearing tests, only one was diagnosed with hearing deficiency at birth.
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Xu T, Zhu W, Wang P, Li H, Yu S. Identification of novel cadherin 23 variants in a Chinese family with hearing loss. Mol Med Rep 2019; 20:2609-2616. [PMID: 31322239 PMCID: PMC6691240 DOI: 10.3892/mmr.2019.10503] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2018] [Accepted: 05/09/2019] [Indexed: 11/09/2022] Open
Abstract
The aim of the present study was to elucidate the role of the non-syndromic autosomal recessive deafness 12 allelic variant of cadherin 23 (CDH23) in Chinese patients with non-syndromic hearing loss. The present study focused on a Chinese family with hearing loss in which there were two siblings with autosomal, recessive deafness, ranging from severe to profound hearing loss over all frequencies. DNA sequencing was used to assess the genetic factors in the disease etiology. The data revealed a compound heterozygous mutation of CDH23 in both patients. Genetic CDH23 variants are known to be responsible for non-syndromic hearing loss, and CDH23 variants frequently occur in various populations, including Japanese and Republic of Korean. Results from the present study, indicated a significant contribution of CDH23 variants to the non-syndromic hearing loss in Chinese patients.
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Affiliation(s)
- Tianni Xu
- Department of Otolaryngology‑Head and Neck Surgery, The First Hospital of Jilin University, Changchun, Jilin 130021, P.R. China
| | - Wei Zhu
- Department of Otolaryngology‑Head and Neck Surgery, The First Hospital of Jilin University, Changchun, Jilin 130021, P.R. China
| | - Ping Wang
- Department of Otolaryngology‑Head and Neck Surgery, The First Hospital of Jilin University, Changchun, Jilin 130021, P.R. China
| | - Haonan Li
- Department of Otolaryngology‑Head and Neck Surgery, The First Hospital of Jilin University, Changchun, Jilin 130021, P.R. China
| | - Shuyuan Yu
- Department of Otolaryngology‑Head and Neck Surgery, The First Hospital of Jilin University, Changchun, Jilin 130021, P.R. China
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Xie L, Chen S, Xu K, Cao HY, Du AN, Bai X, Sun Y, Kong WJ. Reduced postnatal expression of cochlear Connexin26 induces hearing loss and affects the developmental status of pillar cells in a dose-dependent manner. Neurochem Int 2019; 128:196-205. [PMID: 31034913 DOI: 10.1016/j.neuint.2019.04.012] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2019] [Revised: 04/17/2019] [Accepted: 04/19/2019] [Indexed: 10/26/2022]
Abstract
Mutations in the GJB2 gene (which encodes Connexin26 (Cx26)) are the most common cause of non-syndromic deafness. Previous studies showed that an extensive knockout of the Gjb2 gene in cochlear epithelium can cause severe deafness, significant hair cell (HC) loss and failure of pillar cells (a type of supporting cell, PCs) to differentiate in mice. This study aimed to establish different mouse models with gradient reductions of cochlear Cx26 expression and to investigate the effect of different reduced levels of cochlear Cx26 expression on hearing and development of PCs. According to the reduction in the levels of cochlear Cx26, these models were named high knockdown (KD), middle KD and low KD group. In the low KD group, the mice showed normal hearing and well-developed PCs. In the high KD group, up to 90 percent of supporting cells (SCs) lost Cx26 expression. These mice exhibited severe deafness, rapid hair cell degeneration and juvenile PCs. In the middle KD group, nearly half of SCs lost Cx26 expression. However, these mice showed a moderate deafness and a late-onset hair cell loss. Moreover, nearly all the PCs in mice of this group were in a partially differentiated state. These results indicated that reduction of postnatal expression of cochlear Cx26 induces hearing loss in a dose-dependent manner. Null Cx26 in a few SCs affects the developmental status of PCs and the hair cell degeneration pattern. The abnormal developmental status of PCs may be a potential cause of Gjb2-related hearing loss.
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Affiliation(s)
- Le Xie
- Department of Otorhinolaryngology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430022, China
| | - Sen Chen
- Department of Otorhinolaryngology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430022, China
| | - Kai Xu
- Department of Otorhinolaryngology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430022, China
| | - Hai-Yan Cao
- Department of Ultrasound, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430022, China
| | - An-Na Du
- Centre of Instrumental Analysis and Metrology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, 430071, China
| | - Xue Bai
- Department of Otorhinolaryngology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430022, China
| | - Yu Sun
- Department of Otorhinolaryngology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430022, China.
| | - Wei-Jia Kong
- Department of Otorhinolaryngology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430022, China; Institute of Otorhinolaryngology, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430022, China.
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33
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Alimardani M, Hosseini SM, Khaniani MS, Haghi MR, Eslahi A, Farjami M, Chezgi J, Derakhshan SM, Mojarrad M. Targeted Mutation Analysis of the SLC26A4, MYO6, PJVK and CDH23 Genes in Iranian Patients with AR Nonsyndromic Hearing Loss. Fetal Pediatr Pathol 2019; 38:93-102. [PMID: 30582396 DOI: 10.1080/15513815.2018.1547336] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
BACKGROUND Hearing loss (HL) is the most prevalent sensory disorder. The over 100 genes implicated in autosomal recessive nonsyndromic hearing loss (ARNSHL) makes it difficult to analyze and determine the accurate genetic causes of hearing loss. We sought to de?ne the frequency of seven hearing loss-Causing causing genetic Variants in four genes in an Iranian population with hearing loss. MATERIALS AND METHODS One hundred ARNSHL patients with normal GJB2/GJB6 genes were included, and targeted mutations in SLC26A4, MYO6, PJVK and CDH23 genes were analyzed by ARMS-PCR. The negative and positive results were confirmed by the Sanger sequencing. RESULTS We found only two mutations, one in MYO6 (c.554-1 G > A) gene and another in PJVK (c.547C > T). CONCLUSION c.554-1G > A and c.547C > T mutations are responsible for 1% each of the Iranian ARNSHL patients. These genes are not a frequent cause of ARNSHL in an Iranian population.
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Affiliation(s)
- Maliheh Alimardani
- a Neurosciences Research Center , Tabriz University of Medical Science , Tabriz , Iran.,b Department of Medical Genetics , Tabriz University of Medical Sciences , Tabriz , Iran.,c Student Research Committee, Faculty of Medicine , Mashhad University of Medical Sciences , Mashhad , Iran
| | - Seyed Mojtaba Hosseini
- c Student Research Committee, Faculty of Medicine , Mashhad University of Medical Sciences , Mashhad , Iran.,d Department of Medical Genetics , Mashhad University of Medical Sciences , Mashhad , Iran
| | - Mahmoud Shekari Khaniani
- b Department of Medical Genetics , Tabriz University of Medical Sciences , Tabriz , Iran.,e Ebne Sina Medical Genetic Diagnostic Laboratory , Tabriz University of Medical Sciences , Tabriz , Iran
| | - Mohsen Rajati Haghi
- f Department of Head and Neck Surgery, ENT Research Center , Mashhad University of Medical Sciences , Mashhad , Iran
| | - Atieh Eslahi
- c Student Research Committee, Faculty of Medicine , Mashhad University of Medical Sciences , Mashhad , Iran.,d Department of Medical Genetics , Mashhad University of Medical Sciences , Mashhad , Iran
| | - Mashsa Farjami
- c Student Research Committee, Faculty of Medicine , Mashhad University of Medical Sciences , Mashhad , Iran.,d Department of Medical Genetics , Mashhad University of Medical Sciences , Mashhad , Iran
| | - Javad Chezgi
- c Student Research Committee, Faculty of Medicine , Mashhad University of Medical Sciences , Mashhad , Iran.,d Department of Medical Genetics , Mashhad University of Medical Sciences , Mashhad , Iran
| | - Sima Mansoori Derakhshan
- a Neurosciences Research Center , Tabriz University of Medical Science , Tabriz , Iran.,b Department of Medical Genetics , Tabriz University of Medical Sciences , Tabriz , Iran.,e Ebne Sina Medical Genetic Diagnostic Laboratory , Tabriz University of Medical Sciences , Tabriz , Iran
| | - Majid Mojarrad
- d Department of Medical Genetics , Mashhad University of Medical Sciences , Mashhad , Iran.,g Medical Genetics Research Center, School of Medicine , Mashhad University of Medical Sciences , Mashhad , Iran
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34
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Yokota Y, Moteki H, Nishio SY, Yamaguchi T, Wakui K, Kobayashi Y, Ohyama K, Miyazaki H, Matsuoka R, Abe S, Kumakawa K, Takahashi M, Sakaguchi H, Uehara N, Ishino T, Kosho T, Fukushima Y, Usami SI. Frequency and clinical features of hearing loss caused by STRC deletions. Sci Rep 2019; 9:4408. [PMID: 30867468 PMCID: PMC6416315 DOI: 10.1038/s41598-019-40586-7] [Citation(s) in RCA: 42] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2018] [Accepted: 02/19/2019] [Indexed: 12/04/2022] Open
Abstract
Sensorineural hearing loss is a common deficit and mainly occurs due to genetic factors. Recently, copy number variants (CNVs) in the STRC gene have also been recognized as a major cause of genetic hearing loss. We investigated the frequency of STRC deletions in the Japanese population and the characteristics of associated hearing loss. For CNV analysis, we employed a specialized method of Ion AmpliSeqTM sequencing, and confirmed the CNV results via custom array comparative genomic hybridization. We identified 17 probands with STRC homozygous deletions. The prevalence of STRC homozygous deletions was 1.7% in the hearing loss population overall, and 4.3% among mild-to-moderate hearing loss patients. A 2.63% carrier deletion rate was identified in both the hearing loss and the control population with normal hearing. In conclusion, our results show that STRC deletions are the second most common cause of mild-to-moderate hearing loss after the GJB2 gene, which accounts for the majority of genetic hearing loss. The phenotype of hearing loss is congenital and appears to be moderate, and is most likely to be stable without deterioration even after the age of 50. The present study highlights the importance of the STRC gene as a major cause of mild-to-moderate hearing loss.
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Affiliation(s)
- Yoh Yokota
- Department of Otorhinolaryngology, Shinshu University School of Medicine, Matsumoto, Japan
| | - Hideaki Moteki
- Department of Otorhinolaryngology, Shinshu University School of Medicine, Matsumoto, Japan. .,Department of Hearing Implant Sciences, Shinshu University School of Medicine, Matsumoto, Japan.
| | - Shin-Ya Nishio
- Department of Otorhinolaryngology, Shinshu University School of Medicine, Matsumoto, Japan.,Department of Hearing Implant Sciences, Shinshu University School of Medicine, Matsumoto, Japan
| | - Tomomi Yamaguchi
- Department of Medical Genetics, Shinshu University School of Medicine, Matsumoto, Japan.,Center for Medical Genetics, Shinshu University Hospital, Matsumoto, Japan
| | - Keiko Wakui
- Department of Medical Genetics, Shinshu University School of Medicine, Matsumoto, Japan.,Center for Medical Genetics, Shinshu University Hospital, Matsumoto, Japan
| | - Yumiko Kobayashi
- Department of Otolaryngology-Head & Neck Surgery, Iwate Medical University, Morioka, Japan
| | - Kenji Ohyama
- Department of Otorhinolaryngology, Tohoku Rosai Hospital, Sendai, Japan
| | - Hiromitsu Miyazaki
- Department of Otorhinolaryngology-Head and Neck Surgery, Tohoku University School of Medicine, Sendai, Japan
| | - Rina Matsuoka
- Department of Otorhinolaryngology, Juntendo University Faculty of Medicine, Tokyo, Japan
| | - Satoko Abe
- Department of Otorhinolaryngology, Toranomon Hospital, Tokyo, Japan
| | - Kozo Kumakawa
- Department of Otorhinolaryngology, Toranomon Hospital, Tokyo, Japan
| | - Masahiro Takahashi
- Department of Otorhinolaryngology, Head and Neck Surgery, Yokohama City University School of Medicine, Yokohama, Japan.,Department of Otorhinolaryngology, International University of Health and Welfare, Mita Hospital, Tokyo, Japan
| | - Hirofumi Sakaguchi
- Department of Otorhinolaryngology-Head and Neck Surgery, Kyoto Prefectural University of Medicine, Kyoto, Japan
| | - Natsumi Uehara
- Department of Otolaryngology-Head and Neck Surgery, Kobe University School of Medicine, Kobe, Japan
| | - Takashi Ishino
- Department of Otorhinolaryngology, Head and Neck Surgery, Graduate School of Biomedical and Health Sciences, Hiroshima University, Hiroshima, Japan
| | - Tomoki Kosho
- Department of Medical Genetics, Shinshu University School of Medicine, Matsumoto, Japan.,Center for Medical Genetics, Shinshu University Hospital, Matsumoto, Japan.,Research Center for Support to Advanced Science, Shinshu University, Matsumoto, Japan
| | | | - Shin-Ichi Usami
- Department of Otorhinolaryngology, Shinshu University School of Medicine, Matsumoto, Japan.,Department of Hearing Implant Sciences, Shinshu University School of Medicine, Matsumoto, Japan
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35
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Han JJ, Nguyen PD, Oh DY, Han JH, Kim AR, Kim MY, Park HR, Tran LH, Dung NH, Koo JW, Lee JH, Oh SH, Anh Vu H, Choi BY. Elucidation of the unique mutation spectrum of severe hearing loss in a Vietnamese pediatric population. Sci Rep 2019; 9:1604. [PMID: 30733538 PMCID: PMC6367484 DOI: 10.1038/s41598-018-38245-4] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2018] [Accepted: 12/17/2018] [Indexed: 11/09/2022] Open
Abstract
The mutational spectrum of deafness in Indochina Peninsula, including Vietnam, remains mostly undetermined. This significantly hampers the progress toward establishing an effective genetic screening method and early customized rehabilitation modalities for hearing loss. In this study, we evaluated the genetic profile of severe-to-profound hearing loss in a Vietnamese pediatric population using a hierarchical genetic analysis protocol that screened 11 known deafness-causing variants, followed by massively parallel sequencing targeting 129 deafness-associated genes. Eighty-seven children with isolated severe-to-profound non-syndromic hearing loss without family history were included. The overall molecular diagnostic yield was estimated to be 31.7%. The mutational spectrum for severe-to-profound non-syndromic hearing loss in our Vietnamese population was unique: The most prevalent variants resided in the MYO15A gene (7.2%), followed by GJB2 (6.9%), MYO7A (5.5%), SLC26A4 (4.6%), TMC1 (1.8%), ESPN (1.8%), POU3F4 (1.8%), MYH14 (1.8%), EYA1 (1.8%), and MR-RNR1 (1.1%). The unique spectrum of causative genes in the Vietnamese deaf population was similar to that in the southern Chinese deaf population. It is our hope that the mutation spectrum provided here could aid in establishing an efficient protocol for genetic analysis of severe-to-profound hearing loss and a customized screening kit for the Vietnamese population.
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Affiliation(s)
- Jae Joon Han
- Department of Otorhinolaryngology-Head and Neck Surgery, Seoul National University Bundang Hospital, Seongnam, Korea
| | - Pham Dinh Nguyen
- Department of Otorhinolaryngology, Children's Hospital 1, Ho Chi Minh City, Vietnam
| | - Doo-Yi Oh
- Department of Otorhinolaryngology-Head and Neck Surgery, Seoul National University Bundang Hospital, Seongnam, Korea
| | - Jin Hee Han
- Department of Otorhinolaryngology-Head and Neck Surgery, Seoul National University Bundang Hospital, Seongnam, Korea
| | - Ah-Reum Kim
- Biomedical Research Institute, Seoul National University Hospital, Seoul, Korea
| | - Min Young Kim
- Department of Otorhinolaryngology-Head and Neck Surgery, Seoul National University Bundang Hospital, Seongnam, Korea
| | - Hye-Rim Park
- Department of Otorhinolaryngology-Head and Neck Surgery, Seoul National University Bundang Hospital, Seongnam, Korea
| | - Lam Huyen Tran
- Department of Otorhinolaryngology, University of Medicine and Pharmacy at Ho Chi Minh City, Ho Chi Minh City, Vietnam
| | - Nguyen Huu Dung
- Department of Otorhinolaryngology, University of Medicine and Pharmacy at Ho Chi Minh City, Ho Chi Minh City, Vietnam
| | - Ja-Won Koo
- Department of Otorhinolaryngology-Head and Neck Surgery, Seoul National University Bundang Hospital, Seongnam, Korea
| | - Jun Ho Lee
- Department of Otorhinolaryngology-Head and Neck Surgery, Seoul National University Hospital, Seoul, Korea
| | - Seung Ha Oh
- Department of Otorhinolaryngology-Head and Neck Surgery, Seoul National University Hospital, Seoul, Korea
| | - Hoang Anh Vu
- Center for Molecular Biomedicine, University of Medicine and Pharmacy at Ho Chi Minh City, Ho Chi Minh City, Vietnam.
| | - Byung Yoon Choi
- Department of Otorhinolaryngology-Head and Neck Surgery, Seoul National University Bundang Hospital, Seongnam, Korea.
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36
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Abe S, Nishio S, Yokota Y, Moteki H, Kumakawa K, Usami S. Diagnostic pitfalls for GJB2-related hearing loss: A novel deletion detected by Array-CGH analysis in a Japanese patient with congenital profound hearing loss. Clin Case Rep 2018; 6:2111-2116. [PMID: 30455902 PMCID: PMC6230644 DOI: 10.1002/ccr3.1800] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2018] [Revised: 08/05/2018] [Accepted: 08/12/2018] [Indexed: 11/10/2022] Open
Abstract
Here, we report a novel deletion (copy number variation: CNV) in the GJB2 gene observed in a Japanese hearing loss patient. The deleted segment started in the middle of the GJB2 gene, but the GJB6 gene remained intact. This partial deletion in the GJB2 gene highlights the need for further improvements in GJB2 screening.
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Affiliation(s)
- Satoko Abe
- Department of OtorhinolaryngologyToranomon HospitalTokyoJapan
| | - Shin‐ya Nishio
- Department of OtolaryngologyShinshu University School of MedicineNaganoJapan
- Department of Hearing Implant SciencesShinshu University School of MedicineNaganoJapan
| | - Yoh Yokota
- Department of OtolaryngologyShinshu University School of MedicineNaganoJapan
| | - Hideaki Moteki
- Department of OtolaryngologyShinshu University School of MedicineNaganoJapan
- Department of Hearing Implant SciencesShinshu University School of MedicineNaganoJapan
| | - Kozo Kumakawa
- Department of OtorhinolaryngologyToranomon HospitalTokyoJapan
| | - Shin‐ichi Usami
- Department of OtolaryngologyShinshu University School of MedicineNaganoJapan
- Department of Hearing Implant SciencesShinshu University School of MedicineNaganoJapan
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37
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Azadegan‐Dehkordi F, Ahmadi R, Koohiyan M, Hashemzadeh‐Chaleshtori M. Update of spectrum c.35delG and c.‐23+1G>A mutations on the
GJB2
gene in individuals with autosomal recessive nonsyndromic hearing loss. Ann Hum Genet 2018; 83:1-10. [DOI: 10.1111/ahg.12284] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2017] [Revised: 08/01/2018] [Accepted: 08/06/2018] [Indexed: 12/31/2022]
Affiliation(s)
- Fatemeh Azadegan‐Dehkordi
- Cellular and Molecular Research Center, Basic Health Sciences Institute Shahrekord University of Medical Sciences Shahrekord Iran
| | - Reza Ahmadi
- Clinical Biochemistry Research Center, Basic Health Sciences Institute Shahrekord University of Medical Sciences Shahrekord Iran
| | - Mahbobeh Koohiyan
- Medical Plants Research Center, Basic Health Sciences Institute Shahrekord University of Medical Sciences Shahrekord Iran
| | - Morteza Hashemzadeh‐Chaleshtori
- Cellular and Molecular Research Center, Basic Health Sciences Institute Shahrekord University of Medical Sciences Shahrekord Iran
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38
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Shen N, Peng J, Wang X, Zhu Y, Liu W, Liu A, Lu Y. Association between the p.V37I variant of GJB2 and hearing loss: a pedigree and meta-analysis. Oncotarget 2018; 8:46681-46690. [PMID: 28489599 PMCID: PMC5542302 DOI: 10.18632/oncotarget.17325] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2017] [Accepted: 03/19/2017] [Indexed: 12/31/2022] Open
Abstract
Pathogenic variants in the gap junction protein beta-2 (GJB2) gene are the most common cause of hearing loss. Of these, the p.V37I variant of GJB2 has a high allele frequency (up to 10%) in East Asians. Characterization of the phenotypic spectrum associated with p.V37I, as well as the role of this variant in the onset of hearing loss could have a remarkable effect on future diagnostic strategies. Here, we performed a pedigree analysis of unrelated families exhibiting various hearing phenotypes, and then conducted a meta-analysis to comprehensively assess the association between the p.V37I and the risk of hearing loss. Pedigree analyses showed that both homozygous p.V37I variants, as well as compound heterozygous p.V37I with other GJB2 pathogenic variants, contributed to various phenotypes of hearing loss. Meanwhile, meta-analysis demonstrated that, compared with those in the wild type group, both p.V37I homozygotes and compound heterozygous p.V37I variants were at significantly higher risk of developing hearing loss (odds ratios = 7.14 and 3.63; 95% confidence intervals = 3.01-16.95 and 1.38–9.54, respectively). Conversely, heterozygous p.V37I variants alone did not increase the risk of hearing loss. Given the high allele carriage rate of p.V37I (up to 10%) within the general population, our work not only provides information that might influence future genetic screening policies, but also offers insight into clinical risk evaluation and genetic counseling regarding hearing loss.
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Affiliation(s)
- Na Shen
- Department of Laboratory Medicine, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China
| | - Jing Peng
- Department of Laboratory Medicine, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China
| | - Xiong Wang
- Department of Laboratory Medicine, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China
| | - Yaowu Zhu
- Department of Laboratory Medicine, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China
| | - Weiyong Liu
- Department of Laboratory Medicine, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China
| | - Aiguo Liu
- Department of Otorhinolaryngology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China
| | - Yanjun Lu
- Department of Laboratory Medicine, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China
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39
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del Castillo FJ, del Castillo I. DFNB1 Non-syndromic Hearing Impairment: Diversity of Mutations and Associated Phenotypes. Front Mol Neurosci 2017; 10:428. [PMID: 29311818 PMCID: PMC5743749 DOI: 10.3389/fnmol.2017.00428] [Citation(s) in RCA: 55] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2017] [Accepted: 12/07/2017] [Indexed: 02/02/2023] Open
Abstract
The inner ear is a very complex sensory organ whose development and function depend on finely balanced interactions among diverse cell types. The many different kinds of inner ear supporting cells play the essential roles of providing physical and physiological support to sensory hair cells and of maintaining cochlear homeostasis. Appropriately enough, the gene most commonly mutated among subjects with hereditary hearing impairment (HI), GJB2, encodes the connexin-26 (Cx26) gap-junction channel protein that underlies both intercellular communication among supporting cells and homeostasis of the cochlear fluids, endolymph and perilymph. GJB2 lies at the DFNB1 locus on 13q12. The specific kind of HI associated with this locus is caused by recessively-inherited mutations that inactivate the two alleles of the GJB2 gene, either in homozygous or compound heterozygous states. We describe the many diverse classes of genetic alterations that result in DFNB1 HI, such as large deletions that either destroy the GJB2 gene or remove a regulatory element essential for GJB2 expression, point mutations that interfere with promoter function or splicing, and small insertions or deletions and nucleotide substitutions that target the GJB2 coding sequence. We focus on how these alterations disrupt GJB2 and Cx26 functions and on their different effects on cochlear development and physiology. We finally discuss the diversity of clinical features of DFNB1 HI as regards severity, age of onset, inner ear malformations and vestibular dysfunction, highlighting the areas where future research should be concentrated.
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Affiliation(s)
- Francisco J. del Castillo
- Servicio de Genética, Hospital Universitario Ramón y Cajal, IRYCIS, Madrid, Spain
- Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), Madrid, Spain
| | - Ignacio del Castillo
- Servicio de Genética, Hospital Universitario Ramón y Cajal, IRYCIS, Madrid, Spain
- Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), Madrid, Spain
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40
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Shaikh H, Waryah AM, Narsani AK, Iqbal M, Shahzad M, Waryah YM, Shaikh N, Mahmood A. Genetic Testing of Non-familial Deaf Patients for CIB2 and GJB2 Mutations: Phenotype and Genetic Counselling. Biochem Genet 2017; 55:410-420. [PMID: 29086887 DOI: 10.1007/s10528-017-9828-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2017] [Accepted: 09/19/2017] [Indexed: 02/02/2023]
Abstract
CIB2 and GJB2 genes variants contribute significantly in familial cases of prelingual recessive hearing loss (HL). This study was aimed to determine the CIB2 and GJB2 variants and associated phenotype in 150 non-familial individuals with HL. After getting informed consent, 150 non-familial deaf patients were enrolled and blood samples were obtained for DNA extraction. Pure tone air conduction audiometry was performed. Coding exons of CIB2 and GJB2 genes were Sanger sequenced. A tetra primer ARMS assay was developed for recurrent CIB2 variant. Four bi-allelic GJB2 variants, c.71G>A p.(Trp24*), c.231G>A p.(Trp77*), c.235delC p.(Leu79Cysfs3*) and c.35delG p.(Gly11Leufs24*), were found in nine hearing impaired individuals. We also found four homozygotes and five carriers of c.380G>A p. (Arg127His) variant of controversial clinical significance. CIB2 sequencing revealed single recurrent variant c.272T>C p. (Phe91Ser) segregating with HL in ten individuals. Among our patients, c.71G>A (p.Trp24*) was the most common variant, accounted for 45% of GJB2 variants. Two known GJB2 variants, c.235delC p. (Leu79Cysfs3*) and c.310del14 p. (Lys105Argfs2*), are reported here for the first time in Pakistani population. Our data further support the benign nature of c.380G>A p. (Arg127His) variant. For CIB2, c.272T>C p. (Phe91Ser) is the second common cause of HL among our sporadic cases. Phenotypically, in our patients, individuals homozygous for GJB2 variants had profound HL, whereas CIB2 homozygotes had severe to profound prelingual HL. Our results suggest that GJB2 and CIB2 are common cause of HL in different Pakistani ethnicities.
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Affiliation(s)
- Hina Shaikh
- Molecular Biology and Genetics Department, Medical Research Center, Liaquat University of Medical and Health Sciences, Jamshoro, Pakistan
| | - Ali M Waryah
- Molecular Biology and Genetics Department, Medical Research Center, Liaquat University of Medical and Health Sciences, Jamshoro, Pakistan.
| | - Ashok K Narsani
- Institute of Ophthalmology, Liaquat University of Medical and Health Sciences, Jamshoro, Pakistan
| | - Muhammad Iqbal
- Department of Biochemistry and Biotechnology, Islamia University, Bahawalpur, Pakistan
| | - Mohsin Shahzad
- Department of Molecular Biology, Shaheed Zulfiqar Ali Bhutto Medical University, Islamabad, Pakistan
| | - Yar M Waryah
- Molecular Biology and Genetics Department, Medical Research Center, Liaquat University of Medical and Health Sciences, Jamshoro, Pakistan
| | - Naila Shaikh
- Molecular Biology and Genetics Department, Medical Research Center, Liaquat University of Medical and Health Sciences, Jamshoro, Pakistan
| | - Amber Mahmood
- Molecular Biology and Genetics Department, Medical Research Center, Liaquat University of Medical and Health Sciences, Jamshoro, Pakistan
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41
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Luo J, Bai X, Zhang F, Xiao Y, Gu L, Han Y, Fan Z, Li J, Xu L, Wang H. Prevalence of Mutations in Deafness-Causing Genes in Cochlear Implanted Patients with Profound Nonsyndromic Sensorineural Hearing Loss in Shandong Province, China. Ann Hum Genet 2017; 81:258-266. [PMID: 28786104 DOI: 10.1111/ahg.12207] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2017] [Revised: 06/29/2017] [Accepted: 06/30/2017] [Indexed: 11/27/2022]
Abstract
The mutations of GJB2, SLC26A4, and mtDNA12SrRNA are the most common inherited causes of nonsyndromic sensorineural hearing loss (NSHL) in China, yet previous genetic screenings were mainly carried on patients with moderate-to-profound impairment. We aimed to detect the mutation frequencies in NSHL population within a more specified range of severity. Patients with profound NSHL who had undergone cochlear implantation in the Shandong Provincial Hospital (Shandong, China) were recruited. The majority (n = 472) were between 0.7 and 6 years old, and the remaining (n = 63) were between 6 and 70 years old. In total, 115 mutation alleles of the three genes were screened with SNP scan assay. Of the patients, 19.44% (104/535) were found to have GJB2 mutations, and the most common allele was c.235delC, followed by c.299_300delAT and c.109G>A. SLC26A4 mutations were detected in 13.46% patients (72/535), and the most common allele was c.919-2A>G (IVS7-2A>G), followed by c.1174A>T and c.2168A>G. Seven patients (1.31%) carried mutations in mtDNA12SrRNA, with the alleles of m.1555A>G and m.1494C>T. We found the allele frequency of c.109G>A (GJB2) was relatively lower in the profound NSHL population in comparison to the moderate-to-profound ones, and the c.1174A>T (SLC26A4) relatively higher. It suggests those mutations may be connected with the degree of deafness, which needs more observations and analyses to support.
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Affiliation(s)
- Jianfen Luo
- Department of Otorhinolaryngology Head and Neck Surgery, Shandong Provincial Hospital Affiliated to Shandong University, Shandong, China.,Shandong Provincial Key Laboratory of Otology, Shandong, China
| | - Xiaohui Bai
- Department of Otorhinolaryngology Head and Neck Surgery, Shandong Provincial Hospital Affiliated to Shandong University, Shandong, China.,Shandong Provincial Key Laboratory of Otology, Shandong, China
| | - Fengguo Zhang
- Department of Otorhinolaryngology Head and Neck Surgery, Shandong Provincial Hospital Affiliated to Shandong University, Shandong, China.,Shandong Provincial Key Laboratory of Otology, Shandong, China
| | - Yun Xiao
- Department of Otorhinolaryngology Head and Neck Surgery, Shandong Provincial Hospital Affiliated to Shandong University, Shandong, China.,Shandong Provincial Key Laboratory of Otology, Shandong, China
| | - Lintao Gu
- Department of Otorhinolaryngology Head and Neck Surgery, Shandong Provincial Hospital Affiliated to Shandong University, Shandong, China
| | - Yuechen Han
- Department of Otorhinolaryngology Head and Neck Surgery, Shandong Provincial Hospital Affiliated to Shandong University, Shandong, China.,Shandong Provincial Key Laboratory of Otology, Shandong, China
| | - Zhaomin Fan
- Department of Otorhinolaryngology Head and Neck Surgery, Shandong Provincial Hospital Affiliated to Shandong University, Shandong, China.,Shandong Provincial Key Laboratory of Otology, Shandong, China
| | - Jianfeng Li
- Department of Otorhinolaryngology Head and Neck Surgery, Shandong Provincial Hospital Affiliated to Shandong University, Shandong, China.,Shandong Provincial Key Laboratory of Otology, Shandong, China
| | - Lei Xu
- Department of Otorhinolaryngology Head and Neck Surgery, Shandong Provincial Hospital Affiliated to Shandong University, Shandong, China.,Shandong Provincial Key Laboratory of Otology, Shandong, China
| | - Haibo Wang
- Department of Otorhinolaryngology Head and Neck Surgery, Shandong Provincial Hospital Affiliated to Shandong University, Shandong, China.,Shandong Provincial Key Laboratory of Otology, Shandong, China
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Bai D, Yue B, Aoyama H. Crucial motifs and residues in the extracellular loops influence the formation and specificity of connexin docking. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2017; 1860:9-21. [PMID: 28693896 DOI: 10.1016/j.bbamem.2017.07.003] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/30/2017] [Revised: 06/25/2017] [Accepted: 07/03/2017] [Indexed: 12/19/2022]
Abstract
Most of the early studies on gap junction (GJ) channel function and docking compatibility were on rodent connexins, while recent research on GJ channels gradually shifted from rodent to human connexins largely due to the fact that mutations in many human connexin genes are found to associate with inherited human diseases. The studies on human connexins have revealed some key differences from those found in rodents, calling for a comprehensive characterization of human GJ channels. Functional studies revealed that docking and formation of functional GJ channels between two hemichannels are possible only between docking-compatible connexins. Two groups of docking-compatible rodent connexins have been identified. Compatibility is believed to be due to their amino acid residue differences at the extracellular loop domains (E1 and E2). Sequence alignment of the E1 and E2 domains of all connexins known to make GJs revealed that they are highly conserved and show high sequence identity with human Cx26, which is the only connexin with near atomic resolution GJ structure. We hypothesize that different connexins have a similar structure as that of Cx26 at the E1 and E2 domains and use the corresponding residues in their E1 and E2 domains for docking. Based on the Cx26 GJ structure and sequence analysis of well-studied connexins, we propose that the E1-E1 docking interactions are staggered with each E1 interacting with two E1s on the docked connexon. The putative E1 docking residues are conserved in both docking-compatible and -incompatible connexins, indicating that E1 does not likely serve a role in docking compatibility. However, in the case of E2-E2 docking interactions, the putative docking residues are only conserved within the docking-compatible connexins, suggesting the E2 is likely to serve the function of docking compatibility. Docking compatibility studies on human connexins have attracted a lot of attention due to the fact that putative docking residues are mutational hotspots for several connexin-linked human diseases. This article is part of a Special Issue entitled: Gap Junction Proteins edited by Jean Claude Herve.
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Affiliation(s)
- Donglin Bai
- Department of Physiology and Pharmacology, University of Western Ontario, London, Ontario, Canada.
| | - Benny Yue
- Department of Physiology and Pharmacology, University of Western Ontario, London, Ontario, Canada
| | - Hiroshi Aoyama
- Graduate School of Pharmaceutical Sciences, Osaka University, Osaka, Japan
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Nishio SY, Usami SI. Outcomes of cochlear implantation for the patients with specific genetic etiologies: a systematic literature review. Acta Otolaryngol 2017; 137:730-742. [PMID: 28498079 DOI: 10.1080/00016489.2016.1276303] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
CONCLUSION Most of the cases with gene mutations of intra-cochlear etiology showed relatively good CI outcomes. To progress toward more solid evidence-based CI intervention, a greater number of reports including CI outcomes for specific gene mutations are desired. BACKGROUND Cochlear implantation (CI) is the most important and effective treatment for patients with profound sensorineural hearing loss. However, the outcomes of CI vary among patients. One of the reasons of this heterogeneous outcome for cochlear implantation is thought to be the heterogeneous nature of hearing loss. Indeed, genetic factors, the most common etiology in severe-to-profound hearing loss, might be one of the key determinants of outcomes for CI and electric acoustic stimulation (EAS). Patients with genetic causes involving an 'intra-cochlear' etiology show good CI/EAS outcomes. REVIEW This review article aimed to summarize the reports on CI/EAS outcomes in patients with special genetic causes as well as to assist in future clinical decision-making. Most of the cases were suspected of an intra-cochlear etiology, such as those with GJB2, SLC26A4, and OTOF mutations, which showed relatively good CI outcomes. However, there have only been a limited number of reports on patients with other gene mutations.
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Affiliation(s)
- Shin-ya Nishio
- Department of Otorhinolaryngology, Shinshu University School of Medicine, Matsumoto, Nagano, Japan
| | - Shin-ichi Usami
- Department of Otorhinolaryngology, Shinshu University School of Medicine, Matsumoto, Nagano, Japan
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Amundsen VV, Wie OB, Myhrum M, Bunne M. The impact of ethnicity on cochlear implantation in Norwegian children. Int J Pediatr Otorhinolaryngol 2017; 93:30-36. [PMID: 28109494 DOI: 10.1016/j.ijporl.2016.12.002] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/23/2016] [Revised: 11/28/2016] [Accepted: 12/01/2016] [Indexed: 10/20/2022]
Abstract
OBJECTIVES To explore the impact of parental ethnicity on cochlear implantation in children in Norway with regard to incidence rates of cochlear implants (CIs), comorbidies, age at onset of profound deafness (AOD), age at first implantation, uni- or bilateral CI, and speech recognition. METHOD This retrospective cohort study included all children (N = 278) aged <18 years in Norway who received their first CI during the years 2004-2010. RESULTS 86 children (30.9%) in our study sample had parents of non-Nordic ethnicity, of whom 46 were born in Nordic countries with two non-Nordic parents. Compared with the background population, children with non-Nordic parents were 1.9 times more likely to have received CI than Nordic children (i.e., born in Nordic countries with Nordic parents). When looking at AOD, uni-vs. bilateral CIs, and comorbidities, no significant differences were found between Nordic children and children with a non-Nordic ethnicity. Among children with AOD <1 year (n = 153), those born in non-Nordic countries with two non-Nordic parents (n = 6) and adopted non-Nordic children (n = 6) received their first CI on average 14.9 and 21.1 months later than Nordic children (n = 104), respectively (p = 0.006 and 0.005). Among children with AOD <1 year, those born in Nordic countries with two non-Nordic parents (n = 31) received their CI at an older age than Nordic children, but this difference was not significant after adjusting for calendar year of implantation and excluding comorbidity as a potential cause of delayed implantation. The mean age at implantation for children with AOD <1 year dropped 2.3 months/year over the study period. The mean monosyllable speech recognition score was 84.7% for Nordic children and 76.3% for children born in Norway with two non-Nordic parents (p = 0.002). CONCLUSIONS The incidence of CI was significantly higher in children with a non-Nordic vs. a Nordic ethnicity, reflecting a higher incidence of profound deafness. Children born in Norway have equal access to CIs regardless of their ethnicity, but despite being born and receiving care in Norway, prelingually deaf children with non-Nordic parents are at risk of receiving CI later than Nordic children. Moreover, prelingually deaf children who arrive in Norway at an older age may be at risk for a worse prognosis after receiving a CI due to lack of auditory stimulation in early childhood, which is critical for language development and late implantation; this is a serious issue with regard to deafness among refugees.
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Affiliation(s)
- Viktoria Vedeler Amundsen
- Institute of Clinical Medicine, Faculty of Medicine, University of Oslo, P.O. Box 1078 Blindern, N-0316 Oslo, Norway.
| | - Ona Bø Wie
- Department of Special Needs Education, Faculty of Education, University of Oslo, P.O. Box 1140 Blindern, N-0318 Oslo, Norway; Department of Otorhinolaryngology, Division of Head and Neck Surgery, Oslo University Hospital Rikshospitalet, P.O. Box 4950, N-0424 Oslo, Norway.
| | - Marte Myhrum
- Institute of Clinical Medicine, Faculty of Medicine, University of Oslo, P.O. Box 1078 Blindern, N-0316 Oslo, Norway; Department of Otorhinolaryngology, Division of Head and Neck Surgery, Oslo University Hospital Rikshospitalet, P.O. Box 4950, N-0424 Oslo, Norway.
| | - Marie Bunne
- Department of Otorhinolaryngology, Division of Head and Neck Surgery, Oslo University Hospital Rikshospitalet, P.O. Box 4950, N-0424 Oslo, Norway.
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Nishio SY, Usami SI. The Clinical Next-Generation Sequencing Database: A Tool for the Unified Management of Clinical Information and Genetic Variants to Accelerate Variant Pathogenicity Classification. Hum Mutat 2017; 38:252-259. [PMID: 28008688 PMCID: PMC5324660 DOI: 10.1002/humu.23160] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2016] [Revised: 11/27/2016] [Accepted: 12/15/2016] [Indexed: 12/11/2022]
Abstract
Recent advances in next‐generation sequencing (NGS) have given rise to new challenges due to the difficulties in variant pathogenicity interpretation and large dataset management, including many kinds of public population databases as well as public or commercial disease‐specific databases. Here, we report a new database development tool, named the “Clinical NGS Database,” for improving clinical NGS workflow through the unified management of variant information and clinical information. This database software offers a two‐feature approach to variant pathogenicity classification. The first of these approaches is a phenotype similarity‐based approach. This database allows the easy comparison of the detailed phenotype of each patient with the average phenotype of the same gene mutation at the variant or gene level. It is also possible to browse patients with the same gene mutation quickly. The other approach is a statistical approach to variant pathogenicity classification based on the use of the odds ratio for comparisons between the case and the control for each inheritance mode (families with apparently autosomal dominant inheritance vs. control, and families with apparently autosomal recessive inheritance vs. control). A number of case studies are also presented to illustrate the utility of this database.
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Affiliation(s)
- Shin-Ya Nishio
- Department of Otorhinolaryngology, Shinshu University School of Medicine, Matsumoto City, Japan
| | - Shin-Ichi Usami
- Department of Otorhinolaryngology, Shinshu University School of Medicine, Matsumoto City, Japan
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Du Y, Huang L, Cheng X, Zhao L, Ruan Y, Ni T. Analysis of p.V37I compound heterozygous mutations in the GJB2 gene in Chinese infants and young children. Biosci Trends 2016; 10:220-6. [PMID: 27350192 DOI: 10.5582/bst.2016.01096] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
The p.V37I (c.109G>A) mutation in the GJB2 gene is the common frequent cause of congenital deafness; however, its pathogenicity is debated. The present study investigated the prevalence of p.V37I in Chinese infants and young children and associated clinical characteristics. The subjects of the present study were screened for mutations in GJB2 (235delC, 299delAT, 176dell6, 35delG), SLC26A4 (IVS7-2A>G, 2168A>G), GJB3 (538C>T), and in the mitochondrial 12S rRNA gene (1555A>G, 1494C>T). Subjects with p.V37I underwent an audiological evaluation. GJB2 exon sequencing revealed that 20 subjects had p.V37I compound heterozygous mutations, one of whom had a family history; the mutations included c.235delC/p.V37I (n = 12), c.299AT/p.V37I (n = 7), and c.176del16/p.V37I (n = 1). Of the 20 subjects, 12 were referred for Universal Newborn Hearing Screening (UNHS). Nine of the 20 subjects had mild hearing loss in the better ear and 5 had moderate hearing loss in the better ear while 4 had normal hearing. Among subjects with the c.235delC/p.V37I mutation, 5 had mild hearing loss and 2 had moderate hearing loss while 3 had normal hearing. Among subjects with the c.299AT/p.V37I mutation, 3 had mld hearing loss and 3 had moderate hearing loss while 1 had normal hearing. One subject with the c.176del16/p.V37I mutation had mild hearing loss. Few studies have reported on the clinical characteristics of Chinese infants with p.V37I compound heterozygous mutations identified via screening for deafness genes and GJB2 sequencing. The c.235delC/p.V37I mutation was the most prevalent mutation found in subjects. The degree of hearing loss associated with p.V37I compound heterozygous mutations was mainly mild to moderate.
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Affiliation(s)
- Yating Du
- Beijing Tongren Hospital, Capital Medical University
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Wu CC, Tsai CH, Hung CC, Lin YH, Lin YH, Huang FL, Tsao PN, Su YN, Lee YL, Hsieh WS, Hsu CJ. Newborn genetic screening for hearing impairment: a population-based longitudinal study. Genet Med 2016; 19:6-12. [DOI: 10.1038/gim.2016.66] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2016] [Accepted: 04/12/2016] [Indexed: 12/11/2022] Open
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Barashkov NA, Pshennikova VG, Posukh OL, Teryutin FM, Solovyev AV, Klarov LA, Romanov GP, Gotovtsev NN, Kozhevnikov AA, Kirillina EV, Sidorova OG, Vasilyevа LM, Fedotova EE, Morozov IV, Bondar AA, Solovyevа NA, Kononova SK, Rafailov AM, Sazonov NN, Alekseev AN, Tomsky MI, Dzhemileva LU, Khusnutdinova EK, Fedorova SA. Spectrum and Frequency of the GJB2 Gene Pathogenic Variants in a Large Cohort of Patients with Hearing Impairment Living in a Subarctic Region of Russia (the Sakha Republic). PLoS One 2016; 11:e0156300. [PMID: 27224056 PMCID: PMC4880331 DOI: 10.1371/journal.pone.0156300] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2016] [Accepted: 05/12/2016] [Indexed: 11/29/2022] Open
Abstract
Pathogenic variants in the GJB2 gene, encoding connexin 26, are known to be a major cause of hearing impairment (HI). More than 300 allelic variants have been identified in the GJB2 gene. Spectrum and allelic frequencies of the GJB2 gene vary significantly among different ethnic groups worldwide. Until now, the spectrum and frequency of the pathogenic variants in exon 1, exon 2 and the flanking intronic regions of the GJB2 gene have not been described thoroughly in the Sakha Republic (Yakutia), which is located in a subarctic region in Russia. The complete sequencing of the non-coding and coding regions of the GJB2 gene was performed in 393 patients with HI (Yakuts—296, Russians—51, mixed and other ethnicities—46) and in 187 normal hearing individuals of Yakut (n = 107) and Russian (n = 80) populations. In the total sample (n = 580), we revealed 12 allelic variants of the GJB2 gene, 8 of which were recessive pathogenic variants. Ten genotypes with biallelic recessive pathogenic variants in the GJB2 gene (in a homozygous or a compound heterozygous state) were found in 192 out of 393 patients (48.85%). We found that the most frequent GJB2 pathogenic variant in the Yakut patients was c.-23+1G>A (51.82%) and that the second most frequent was c.109G>A (2.37%), followed by c.35delG (1.64%). Pathogenic variants с.35delG (22.34%), c.-23+1G>A (5.31%), and c.313_326del14 (2.12%) were found to be the most frequent among the Russian patients. The carrier frequencies of the c.-23+1G>A and с.109G>A pathogenic variants in the Yakut control group were 10.20% and 2.80%, respectively. The carrier frequencies of с.35delG and c.101T>C were identical (2.5%) in the Russian control group. We found that the contribution of the GJB2 gene pathogenic variants in HI in the population of the Sakha Republic (48.85%) was the highest among all of the previously studied regions of Asia. We suggest that extensive accumulation of the c.-23+1G>A pathogenic variant in the indigenous Yakut population (92.20% of all mutant chromosomes in patients) and an extremely high (10.20%) carrier frequency in the control group may indicate a possible selective advantage for the c.-23+1G>A carriers living in subarctic climate.
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Affiliation(s)
- Nikolay A. Barashkov
- Department of Molecular Genetics, Federal State Budgetary Scientific Institution “Yakut Science Centre of Complex Medical Problems,” Yakutsk, Russian Federation
- Laboratory of Molecular Biology, Institute of Natural Sciences, M.K. Ammosov North-Eastern Federal University, Yakutsk, Russian Federation
- * E-mail:
| | - Vera G. Pshennikova
- Department of Molecular Genetics, Federal State Budgetary Scientific Institution “Yakut Science Centre of Complex Medical Problems,” Yakutsk, Russian Federation
- Laboratory of Molecular Biology, Institute of Natural Sciences, M.K. Ammosov North-Eastern Federal University, Yakutsk, Russian Federation
| | - Olga L. Posukh
- Laboratory of Human Molecular Genetics, Federal Research Center, Institute of Cytology and Genetics, Siberian Branch of the Russian Academy of Sciences, Novosibirsk, Russian Federation
- Novosibirsk State University, Novosibirsk, Russian Federation
| | - Fedor M. Teryutin
- Department of Molecular Genetics, Federal State Budgetary Scientific Institution “Yakut Science Centre of Complex Medical Problems,” Yakutsk, Russian Federation
- Laboratory of Molecular Biology, Institute of Natural Sciences, M.K. Ammosov North-Eastern Federal University, Yakutsk, Russian Federation
| | - Aisen V. Solovyev
- Department of Molecular Genetics, Federal State Budgetary Scientific Institution “Yakut Science Centre of Complex Medical Problems,” Yakutsk, Russian Federation
- Laboratory of Molecular Biology, Institute of Natural Sciences, M.K. Ammosov North-Eastern Federal University, Yakutsk, Russian Federation
| | - Leonid A. Klarov
- Department of Molecular Genetics, Federal State Budgetary Scientific Institution “Yakut Science Centre of Complex Medical Problems,” Yakutsk, Russian Federation
- Department of Radiology, Republican Hospital # 2 –Center of Emergency Medicine, Ministry of Public Health of the Sakha Republic, Yakutsk, Russian Federation
| | - Georgii P. Romanov
- Department of Molecular Genetics, Federal State Budgetary Scientific Institution “Yakut Science Centre of Complex Medical Problems,” Yakutsk, Russian Federation
- Laboratory of Molecular Biology, Institute of Natural Sciences, M.K. Ammosov North-Eastern Federal University, Yakutsk, Russian Federation
| | - Nyurgun N. Gotovtsev
- Department of Molecular Genetics, Federal State Budgetary Scientific Institution “Yakut Science Centre of Complex Medical Problems,” Yakutsk, Russian Federation
- Laboratory of Molecular Biology, Institute of Natural Sciences, M.K. Ammosov North-Eastern Federal University, Yakutsk, Russian Federation
| | - Andrey A. Kozhevnikov
- Republican Centre of Professional Pathology, Republican Hospital # 2 –Center of Emergency Medicine, Ministry of Public Health of the Sakha Republic, Yakutsk, Russian Federation
| | - Elena V. Kirillina
- Institute of Foreign Philology and Regional Studies, M.K. Ammosov North-Eastern Federal University, Yakutsk, Russian Federation
| | - Oksana G. Sidorova
- Department of Molecular Genetics, Federal State Budgetary Scientific Institution “Yakut Science Centre of Complex Medical Problems,” Yakutsk, Russian Federation
| | - Lena M. Vasilyevа
- Audiology-Logopaedic Centre, Republican Hospital #1– National Medical Centre, Ministry of Public Health of the Sakha Republic, Yakutsk, Russian Federation
| | - Elvira E. Fedotova
- Audiology-Logopaedic Centre, Republican Hospital #1– National Medical Centre, Ministry of Public Health of the Sakha Republic, Yakutsk, Russian Federation
| | - Igor V. Morozov
- Novosibirsk State University, Novosibirsk, Russian Federation
- SB RAS Genomics Core Facility, Institute of Chemical Biology and Fundamental Medicine, Siberian Branch of the Russian Academy of Sciences, Novosibirsk, Russian Federation
| | - Alexander A. Bondar
- SB RAS Genomics Core Facility, Institute of Chemical Biology and Fundamental Medicine, Siberian Branch of the Russian Academy of Sciences, Novosibirsk, Russian Federation
| | - Natalya A. Solovyevа
- Department of Molecular Genetics, Federal State Budgetary Scientific Institution “Yakut Science Centre of Complex Medical Problems,” Yakutsk, Russian Federation
- Laboratory of Molecular Biology, Institute of Natural Sciences, M.K. Ammosov North-Eastern Federal University, Yakutsk, Russian Federation
| | - Sardana K. Kononova
- Department of Molecular Genetics, Federal State Budgetary Scientific Institution “Yakut Science Centre of Complex Medical Problems,” Yakutsk, Russian Federation
- Laboratory of Molecular Biology, Institute of Natural Sciences, M.K. Ammosov North-Eastern Federal University, Yakutsk, Russian Federation
| | - Adyum M. Rafailov
- Laboratory of Molecular Biology, Institute of Natural Sciences, M.K. Ammosov North-Eastern Federal University, Yakutsk, Russian Federation
| | - Nikolay N. Sazonov
- Department of Biochemistry and Biotechnology, Institute of Natural Sciences, M.K. Ammosov North-Eastern Federal University, Yakutsk, Russian Federation
| | - Anatoliy N. Alekseev
- Institute of Humanitarian Research and Indigenous Peoples of the North, Siberian Branch of the Russian Academy of Sciences, Yakutsk, Russian Federation
| | - Mikhail I. Tomsky
- Department of Molecular Genetics, Federal State Budgetary Scientific Institution “Yakut Science Centre of Complex Medical Problems,” Yakutsk, Russian Federation
| | - Lilya U. Dzhemileva
- Laboratory of Human Molecular Genetics, Institute of Biochemistry and Genetics, Ufa Scientific Centre, Russian Academy of Sciences, Ufa, Russian Federation
- Department of Immunology and Human Reproductive Health, Bashkir State Medical University, Ufa, Russian Federation
| | - Elza K. Khusnutdinova
- Laboratory of Human Molecular Genetics, Institute of Biochemistry and Genetics, Ufa Scientific Centre, Russian Academy of Sciences, Ufa, Russian Federation
- Department of Genetics and Fundamental Medicine, Bashkir State University, Ufa, Russian Federation
| | - Sardana A. Fedorova
- Department of Molecular Genetics, Federal State Budgetary Scientific Institution “Yakut Science Centre of Complex Medical Problems,” Yakutsk, Russian Federation
- Laboratory of Molecular Biology, Institute of Natural Sciences, M.K. Ammosov North-Eastern Federal University, Yakutsk, Russian Federation
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Somatic memory and gain increase as preconditions for tinnitus: Insights from congenital deafness. Hear Res 2016; 333:37-48. [DOI: 10.1016/j.heares.2015.12.018] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/01/2015] [Revised: 11/27/2015] [Accepted: 12/18/2015] [Indexed: 11/19/2022]
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50
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Connexin channels in congenital skin disorders. Semin Cell Dev Biol 2016; 50:4-12. [PMID: 26775130 DOI: 10.1016/j.semcdb.2015.11.018] [Citation(s) in RCA: 57] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2015] [Accepted: 11/23/2015] [Indexed: 11/22/2022]
Abstract
Gap junctions and hemichannels comprised of connexins influence epidermal proliferation and differentiation. Significant advances in our understanding of the functional role of connexins in the skin have been made by studying the diseases caused by connexin mutations. Eleven clinically defined cutaneous disorders with an overlapping spectrum of phenotypes are caused by mutations in five different connexin genes, highlighting that disease presentation must be deciphered with an understanding of how connexin functions are affected. Increasing evidence suggests that the skin diseases produced by connexin mutations result from dominant gains of function. In palmoplantar keratoderma with deafness, the connexin 26 mutations transdominantly alter the function of wild-type connexin 43 and create leaky heteromeric hemichannels. In keratitis-ichthyosis-deafness syndrome, different connexin 26 mutations can either form dominant hemichannels with altered calcium regulation or increased calcium permeability, leading to clinical subtypes of this syndrome. It is only with detailed understanding of these subtle functional differences that we can hope to create successful pathophysiology driven therapies for the connexin skin disorders.
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