1
|
Chen PY, Yang TW, Tseng YS, Tsai CY, Yeh CS, Lee YH, Lin PH, Lin TC, Wu YJ, Yang TH, Chiang YT, Hsu JSJ, Hsu CJ, Chen PL, Chou CF, Wu CC. Machine learning-based longitudinal prediction for GJB2-related sensorineural hearing loss. Comput Biol Med 2024; 176:108597. [PMID: 38763069 DOI: 10.1016/j.compbiomed.2024.108597] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2023] [Revised: 05/09/2024] [Accepted: 05/10/2024] [Indexed: 05/21/2024]
Abstract
BACKGROUND Recessive GJB2 variants, the most common genetic cause of hearing loss, may contribute to progressive sensorineural hearing loss (SNHL). The aim of this study is to build a realistic predictive model for GJB2-related SNHL using machine learning to enable personalized medical planning for timely intervention. METHOD Patients with SNHL with confirmed biallelic GJB2 variants in a nationwide cohort between 2005 and 2022 were included. Different data preprocessing protocols and computational algorithms were combined to construct a prediction model. We randomly divided the dataset into training, validation, and test sets at a ratio of 72:8:20, and repeated this process ten times to obtain an average result. The performance of the models was evaluated using the mean absolute error (MAE), which refers to the discrepancy between the predicted and actual hearing thresholds. RESULTS We enrolled 449 patients with 2184 audiograms available for deep learning analysis. SNHL progression was identified in all models and was independent of age, sex, and genotype. The average hearing progression rate was 0.61 dB HL per year. The best MAE for linear regression, multilayer perceptron, long short-term memory, and attention model were 4.42, 4.38, 4.34, and 4.76 dB HL, respectively. The long short-term memory model performed best with an average MAE of 4.34 dB HL and acceptable accuracy for up to 4 years. CONCLUSIONS We have developed a prognostic model that uses machine learning to approximate realistic hearing progression in GJB2-related SNHL, allowing for the design of individualized medical plans, such as recommending the optimal follow-up interval for this population.
Collapse
Affiliation(s)
- Pey-Yu Chen
- Department of Otolaryngology, MacKay Memorial Hospital, Taipei, Taiwan; Department of Audiology and Speech-Language Pathology, Mackay Medical College, New Taipei City, Taiwan; Department of Otolaryngology, National Taiwan University Hospital, Taipei, Taiwan
| | - Ta-Wei Yang
- Graduate Institute of Networking and Multimedia, National Taiwan University, Taipei, Taiwan
| | - Yi-Shan Tseng
- Department of Computer Science & Information Engineering, National Taiwan University, Taipei, Taiwan
| | - Cheng-Yu Tsai
- Department of Otolaryngology, National Taiwan University Hospital, Taipei, Taiwan; Graduate Institute of Medical Genomics and Proteomics, National Taiwan University College of Medicine, Taipei, Taiwan
| | - Chiung-Szu Yeh
- Department of Computer Science & Information Engineering, National Taiwan University, Taipei, Taiwan
| | - Yen-Hui Lee
- Department of Otolaryngology, National Taiwan University Biomedical Park Hospital, Hsinchu County, Taiwan; Department of Otolaryngology, National Taiwan University Hospital Hsin-Chu Branch, Hsinchu City, Taiwan; Hearing and Speech Center, National Taiwan University Hospital, Taipei, Taiwan
| | - Pei-Hsuan Lin
- Department of Otolaryngology, National Taiwan University Hospital, Taipei, Taiwan; Graduate Institute of Clinical Medicine, College of Medicine, National Taiwan University, Taipei, Taiwan
| | - Ting-Chun Lin
- Department of Computer Science & Information Engineering, National Taiwan University, Taipei, Taiwan
| | - Yu-Jen Wu
- Department of Computer Science & Information Engineering, National Taiwan University, Taipei, Taiwan
| | - Ting-Hua Yang
- Department of Otolaryngology, National Taiwan University Hospital, Taipei, Taiwan
| | - Yu-Ting Chiang
- Department of Otolaryngology, National Taiwan University Hospital, Taipei, Taiwan; Graduate Institute of Medical Genomics and Proteomics, National Taiwan University College of Medicine, Taipei, Taiwan
| | - Jacob Shu-Jui Hsu
- Graduate Institute of Medical Genomics and Proteomics, National Taiwan University College of Medicine, Taipei, Taiwan
| | - Chuan-Jen Hsu
- Department of Otolaryngology, National Taiwan University Hospital, Taipei, Taiwan; Department of Otorhinolaryngology-Head and Neck Surgery, Taichung Tzu Chi Hospital, Buddhist Tzu Chi Medical Foundation, Taichung, Taiwan; School of Medicine, Tzu Chi University, Hualien, Taiwan
| | - Pei-Lung Chen
- Graduate Institute of Medical Genomics and Proteomics, National Taiwan University College of Medicine, Taipei, Taiwan; Department of Medical Genetics, National Taiwan University Hospital, Taipei, Taiwan
| | - Chen-Fu Chou
- Department of Computer Science & Information Engineering, National Taiwan University, Taipei, Taiwan
| | - Chen-Chi Wu
- Department of Otolaryngology, National Taiwan University Hospital, Taipei, Taiwan; Department of Medical Genetics, National Taiwan University Hospital, Taipei, Taiwan; Department of Medical Research, National Taiwan University Hospital Hsin-Chu Branch, Hsin-Chu, Taiwan.
| |
Collapse
|
2
|
Jahn KN, Morse-Fortier C, Griffin AM, Faller D, Cohen MS, Kenna MA, Doney E, Arenberg JG. Programming Levels and Speech Perception in Pediatric Cochlear Implant Recipients With Enlarged Vestibular Aqueduct or GJB2 Mutation. Otol Neurotol 2023; 44:e273-e280. [PMID: 37167444 PMCID: PMC10176457 DOI: 10.1097/mao.0000000000003879] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
OBJECTIVE To determine the relationship between hearing loss etiology, cochlear implant (CI) programming levels, and speech perception performance in a large clinical cohort of pediatric CI recipients. STUDY DESIGN Retrospective chart review. SETTING Tertiary care hospitals. PATIENTS A total of 136 pediatric CI recipients (218 ears) were included in this study. All patients had diagnoses of either enlarged vestibular aqueduct (EVA) or GJB2 (Connexin-26) mutation confirmed via radiographic data and/or genetic reports. All patients received audiologic care at either Boston Children's Hospital or Massachusetts Eye and Ear in Boston, MA, between the years 1999 and 2020. MAIN OUTCOME MEASURES Electrode impedances and programming levels for each active electrode and speech perception scores were evaluated as a function of etiology (EVA or GJB2 mutation). RESULTS Children with EVA had significantly higher impedances and programming levels (thresholds and upper stimulation levels) than the children with GJB2 mutation. Speech perception scores did not differ as a function of etiology in this sample; rather, they were positively correlated with duration of CI experience (time since implantation). CONCLUSIONS Differences in electrode impedances and CI programming levels suggest that the electrode-neuron interface varies systematically as a function of hearing loss etiology in pediatric CI recipients with EVA and those with GJB2 mutation. Time with the CI was a better predictor of speech perception scores than etiology, suggesting that children can adapt to CI stimulation with experience.
Collapse
Affiliation(s)
- Kelly N Jahn
- Department of Speech, Language, and Hearing, University of Texas at Dallas, Richardson, Texas
| | | | | | - David Faller
- Department of Otolaryngology and Communication Enhancement, Boston Children's Hospital
| | - Michael S Cohen
- Department of Otolaryngology-Head and Neck Surgery, Harvard Medical School, Boston, Massachusetts
| | | | | | | |
Collapse
|
3
|
Jahn KN, Bergan MD, Arenberg JG. Auditory Detection Thresholds and Cochlear Resistivity Differ Between Pediatric Cochlear Implant Listeners With Enlarged Vestibular Aqueduct and Those With Connexin-26 Mutations. Am J Audiol 2020; 29:23-34. [PMID: 31934787 DOI: 10.1044/2019_aja-19-00054] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
Purpose The goal of this study was to evaluate differences in the electrode-neuron interface as a function of hearing loss etiology in pediatric cochlear implant (CI) listeners with enlarged vestibular aqueduct (EVA) syndrome and in those with autosomal recessive connexin-26 mutations (DFNB1). Method Fifteen implanted ears (9 participants, 5 ears with EVA, 10 ears with DFNB1) were assessed. Single-channel auditory detection thresholds were measured using broad and spatially focused electrode configurations (steered quadrupolar; focusing coefficients = 0 and 0.9). Cochlear resistivity estimates were obtained via electrode impedances and electrical field imaging. Between-group differences were evaluated using linear mixed-effects models. Results Children with EVA had significantly higher auditory detection thresholds than children with DFNB1, irrespective of electrode configuration. Between-group differences in thresholds were more pronounced on apical electrodes than on basal electrodes. In the apex, electrode impedances and electrical field imaging values were higher for children with EVA than for those with DFNB1. Conclusions The electrode-neuron interface differs between pediatric CI listeners with DFNB1 and those with EVA. It is possible that optimal clinical interventions may depend, in part, on hearing loss etiology. Future investigations with large samples should investigate individualized CI programming strategies for listeners with EVA and DFNB1.
Collapse
Affiliation(s)
- Kelly N. Jahn
- Department of Otolaryngology–Head and Neck Surgery, Harvard Medical School, Boston, MA
- Eaton-Peabody Laboratories, Massachusetts Eye and Ear Infirmary, Boston
| | - Molly D. Bergan
- Department of Speech and Hearing Sciences, University of Washington, Seattle
| | - Julie G. Arenberg
- Department of Otolaryngology–Head and Neck Surgery, Harvard Medical School, Boston, MA
- Eaton-Peabody Laboratories, Massachusetts Eye and Ear Infirmary, Boston
| |
Collapse
|
4
|
王 现, 赵 雪, 黄 丽, 文 铖, 王 雪, 程 晓. [Analysis of genotypes and hearing phenotypes of mutation infants with deafness]. LIN CHUANG ER BI YAN HOU TOU JING WAI KE ZA ZHI = JOURNAL OF CLINICAL OTORHINOLARYNGOLOGY, HEAD, AND NECK SURGERY 2020; 34:113-118. [PMID: 32086913 PMCID: PMC10128414 DOI: 10.13201/j.issn.1001-1781.2020.02.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Received: 05/11/2019] [Indexed: 06/10/2023]
Abstract
Objective:The aim of this study is to explore the genotype and hearing phenotype of deaf infants with mutation of GJB2 gene. Method:Subjects were 121 infants with GJB2 gene mutations who were treated in the Children's Hearing Diagnosis Center of Beijing Tongren hospital. All subjects were accepted to undertake the universal newborns hearing screening(UNHS) and series of objective audiometry, including auditory brainstem response, distortion product otoacoustic emission, auditory steady-state response and other audiological tests. All subjects were screened for nine pathogenic variants in four genes or all exons of the GJB2 gene, and then were diagnosed as infants with GJB2 gene mutations. Initially, analyzing their genotypes and hearing phenotypes generally. Then, the subjects were divided into two groups according to the genotypes: T/T group(truncated/truncated mutations, 89 cases) and T/NT group(truncated/non-truncated mutations, 32 cases). Chi-square test was used to analyze the results of UNHS, hearing degree, audiogram patterns and symmetry/asymmetry of binaural hearing phenotype. Eventually, analyzing the results of UNHS. Result:The most common truncated mutation was c.235delC(64.88%, 157/242) and the most common non-truncated mutation was c.109G>A(11.16%, 27/242). The homozygous mutation of c.235delC/c.235delC was the dominant in T/T group(38.84%, 47/121), and the compound heterozygous mutation of c.235delC/c.109G>A was the dominant in T/NT group(18.18%, 22/121). 81.82%(99/121) of subjects failed in UNHS, including 74.38%(90/121) with bilateral reference, 7.44%(9/121) with a single pass. The refer rate of UNHS of group T/T and T/NT were 86.52%(77/89) and 68.75%, respectively. There was a statistically significant difference between the two groups(P<0.05). 85.95%(104/121) of subjects were diagnosed as hearing loss and 14.05%(17/121) of subjects were diagnosed as normal hearing. The degree of hearing loss: profound, severe, moderate and mild were 31.40%(38/121), 19.01%(23/121), 24.79%(30/121) and 10.74%(13/121), respectively. There was no subjects with normal hearing in T/T group and individuals with severe and profound hearing loss accounted for the highest proportion(65.17%, 58/89), while in T/NT group, normal hearing accounted for 53.13%(17/32) and mild and moderate hearing loss accounted for the highest proportion(37.5%, 12/32). There was statistically significant difference between the two groups(P<0.05). Of 104 patients(208 ears) with hearing loss, the audiogram patterns: flat, descending, ascending, residual, Valley and other types were 49.03%(102/208), 12.02%(25/208), 8.65%(18/208), 7.69%(16/204), 3.36%(7/204) and 19.23%(40/204), respectively. The two most common types in T/T group were flat(47.19%, 84/178) and other types(20.22%, 36/178), while in T/NT group were flat(60.00%, 18/30) and ascending(20.00%, 6/30). There was statistically significant difference between the two groups(P<0.05). There were 50 cases(48.07%) with symmetrical hearing phenotype and 54 cases(51.93%) with asymmetrical hearing phenotype. Asymmetry was predominant in T/T group(53.93%, 48/89), and symmetry was predominant in T/NT group(60.00%, 9/15). There was no statistically significant difference between the two groups(P>0.05). Conclusion:In this study, c.235delC/c.235delC homozygous mutation was dominant in T/T group and c.235delC/c.109G>A heterozygous mutation was dominant in T/NT Group. The hearing phenotypes in T/T group were mostly bilateral asymmetric severe hearing loss, and those in T/NT Group were bilateral symmetric mild to moderate hearing loss, special attention should be paid to the audiological characteristics of different genotypes.
Collapse
Affiliation(s)
- 现蕾 王
- 首都医科大学附属北京同仁医院耳鼻咽喉头颈外科 北京市耳鼻咽喉科研究所 耳鼻咽喉头颈外科学教育部重点实验室(北京,100005)Department of Otolaryngology Head and Neck Surgery, Beijing Tongren Hospital, Capital Medical University, Beijing Institute of Otolaryngology, Key Laboratory of Otolaryngology Head and Neck Surgery, Capital Medical University, Ministry of Education, Beijing, 100005, China
| | - 雪雷 赵
- 首都医科大学附属北京同仁医院耳鼻咽喉头颈外科 北京市耳鼻咽喉科研究所 耳鼻咽喉头颈外科学教育部重点实验室(北京,100005)Department of Otolaryngology Head and Neck Surgery, Beijing Tongren Hospital, Capital Medical University, Beijing Institute of Otolaryngology, Key Laboratory of Otolaryngology Head and Neck Surgery, Capital Medical University, Ministry of Education, Beijing, 100005, China
| | - 丽辉 黄
- 首都医科大学附属北京同仁医院耳鼻咽喉头颈外科 北京市耳鼻咽喉科研究所 耳鼻咽喉头颈外科学教育部重点实验室(北京,100005)Department of Otolaryngology Head and Neck Surgery, Beijing Tongren Hospital, Capital Medical University, Beijing Institute of Otolaryngology, Key Laboratory of Otolaryngology Head and Neck Surgery, Capital Medical University, Ministry of Education, Beijing, 100005, China
| | - 铖 文
- 首都医科大学附属北京同仁医院耳鼻咽喉头颈外科 北京市耳鼻咽喉科研究所 耳鼻咽喉头颈外科学教育部重点实验室(北京,100005)Department of Otolaryngology Head and Neck Surgery, Beijing Tongren Hospital, Capital Medical University, Beijing Institute of Otolaryngology, Key Laboratory of Otolaryngology Head and Neck Surgery, Capital Medical University, Ministry of Education, Beijing, 100005, China
| | - 雪瑶 王
- 首都医科大学附属北京同仁医院耳鼻咽喉头颈外科 北京市耳鼻咽喉科研究所 耳鼻咽喉头颈外科学教育部重点实验室(北京,100005)Department of Otolaryngology Head and Neck Surgery, Beijing Tongren Hospital, Capital Medical University, Beijing Institute of Otolaryngology, Key Laboratory of Otolaryngology Head and Neck Surgery, Capital Medical University, Ministry of Education, Beijing, 100005, China
| | - 晓华 程
- 首都医科大学附属北京同仁医院耳鼻咽喉头颈外科 北京市耳鼻咽喉科研究所 耳鼻咽喉头颈外科学教育部重点实验室(北京,100005)Department of Otolaryngology Head and Neck Surgery, Beijing Tongren Hospital, Capital Medical University, Beijing Institute of Otolaryngology, Key Laboratory of Otolaryngology Head and Neck Surgery, Capital Medical University, Ministry of Education, Beijing, 100005, China
| |
Collapse
|
5
|
|
6
|
Markova TG, Bliznetz EA, Polyakov AV, Tavartkiladze GA. [Twenty years of clinical studies of GJB2-linked hearing loss in Russia]. Vestn Otorinolaringol 2019; 83:31-36. [PMID: 30113577 DOI: 10.17116/otorino201883431] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
The most common cause of congenital hereditary hearing loss was discovered 20 years ago in 1997 when GJB2 gene was revealed in the first locus of recessive hearing loss DFNB1. It encodes protein connexin 26, a structural component of the intercellular channels. Recessive mutations in this gene cause the congenital bilateral sensorineural hearing loss. For many years the aim of our work was to study the prevalence and clinical manifestations of hereditary hearing loss. Our research can be divided into three stages. In the beginning, we investigated the prevalence of GJB2 mutations in a healthy population and in the people suffering from hearing impairment. Further research was conducted in the field of clinical manifestations and evidence of the congenital character of GJB2-related hearing loss. Currently, we are working on the prevalence of mild and moderate hereditary hearing loss and the probability of its progression. Achievements in molecular genetics make it possible to establish the hereditary character of congenital hearing loss and to avoid repeated family cases. Primary prevention of hereditary hearing loss becomes real by raising the awareness of GJB2 mutations carriers.
Collapse
Affiliation(s)
- T G Markova
- Russian Research Centre for Audiology and Hearing Rehabilitation, Russian Medico-Biological Agency, Moscow, Russia, 117513; Russian Medical Academy of Continuous Professional Education, Ministry of Health of the Russian Federation, Moscow, Russia, 125993
| | - E A Bliznetz
- Laboratory of DNA Diagnostics, Medical Genetic Research Centre, Moscow, Russia, 115478
| | - A V Polyakov
- Laboratory of DNA Diagnostics, Medical Genetic Research Centre, Moscow, Russia, 115478
| | - G A Tavartkiladze
- Russian Research Centre for Audiology and Hearing Rehabilitation, Russian Medico-Biological Agency, Moscow, Russia, 117513; Russian Medical Academy of Continuous Professional Education, Ministry of Health of the Russian Federation, Moscow, Russia, 125993
| |
Collapse
|
7
|
Ponnath A, Depreux FF, Jodelka FM, Rigo F, Farris HE, Hastings ML, Lentz JJ. Rescue of Outer Hair Cells with Antisense Oligonucleotides in Usher Mice Is Dependent on Age of Treatment. J Assoc Res Otolaryngol 2018; 19:1-16. [PMID: 29027038 PMCID: PMC5783922 DOI: 10.1007/s10162-017-0640-x] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2017] [Accepted: 09/04/2017] [Indexed: 12/29/2022] Open
Abstract
The absence of functional outer hair cells is a component of several forms of hereditary hearing impairment, including Usher syndrome, the most common cause of concurrent hearing and vision loss. Antisense oligonucleotide (ASO) treatment of mice with the human Usher mutation, Ush1c c.216G>A, corrects gene expression and significantly improves hearing, as measured by auditory-evoked brainstem responses (ABRs), as well as inner and outer hair cell (IHC and OHC) bundle morphology. However, it is not clear whether the improvement in hearing achieved by ASO treatment involves the functional rescue of outer hair cells. Here, we show that Ush1c c.216AA mice lack OHC function as evidenced by the absence of distortion product otoacoustic emissions (DPOAEs) in response to low-, mid-, and high-frequency tone pairs. This OHC deficit is rescued by treatment with an ASO that corrects expression of Ush1c c.216G>A. Interestingly, although rescue of inner hairs cells, as measured by ABR, is achieved by ASO treatment as late as 7 days after birth, rescue of outer hair cells, measured by DPOAE, requires treatment before post-natal day 5. These results suggest that ASO-mediated rescue of both IHC and OHC function is age dependent and that the treatment window is different for the different cell types. The timing of treatment for congenital hearing disorders is of critical importance for the development of drugs such ASO-29 for hearing rescue.
Collapse
Affiliation(s)
- Abhilash Ponnath
- Neuroscience Center of Excellence, Louisiana State University Health Sciences Center, 2020 Gravier Street, 8th Floor, New Orleans, LA, 70112, USA
| | - Frederic F Depreux
- Department of Cell Biology and Anatomy, Chicago Medical School, Rosalind Franklin University of Medicine and Science, 3333 Green Bay Rd, North Chicago, IL, 60064, USA
| | - Francine M Jodelka
- Department of Cell Biology and Anatomy, Chicago Medical School, Rosalind Franklin University of Medicine and Science, 3333 Green Bay Rd, North Chicago, IL, 60064, USA
| | - Frank Rigo
- Ionis Pharmaceuticals, 2855 Gazelle Court, Carlsbad, CA, 92010, USA
| | - Hamilton E Farris
- Neuroscience Center of Excellence, Louisiana State University Health Sciences Center, 2020 Gravier Street, 8th Floor, New Orleans, LA, 70112, USA
- Department of Cell Biology and Anatomy, Louisiana State University Health Sciences Center, 1901 Perdido Street, New Orleans, LA, 70112, USA
- Department of Otolaryngology and Biocommunications, Louisiana State University Health Sciences Center, 533 Bolivar Street, New Orleans, LA, 70112, USA
| | - Michelle L Hastings
- Department of Cell Biology and Anatomy, Chicago Medical School, Rosalind Franklin University of Medicine and Science, 3333 Green Bay Rd, North Chicago, IL, 60064, USA.
| | - Jennifer J Lentz
- Neuroscience Center of Excellence, Louisiana State University Health Sciences Center, 2020 Gravier Street, 8th Floor, New Orleans, LA, 70112, USA.
- Department of Otolaryngology and Biocommunications, Louisiana State University Health Sciences Center, 533 Bolivar Street, New Orleans, LA, 70112, USA.
| |
Collapse
|
8
|
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.
Collapse
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
| |
Collapse
|
9
|
Leclère JC, Le Gac MS, Le Maréchal C, Ferec C, Marianowski R. GJB2 mutations: Genotypic and phenotypic correlation in a cohort of 690 hearing-impaired patients, toward a new mutation? Int J Pediatr Otorhinolaryngol 2017; 102:80-85. [PMID: 29106882 DOI: 10.1016/j.ijporl.2017.09.011] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/16/2016] [Revised: 09/10/2017] [Accepted: 09/11/2017] [Indexed: 10/18/2022]
Abstract
OBJECTIVES To analyze the clinical features of hearing impairment and to search for correlations with the genotype in patients with GJB2 mutations. DESIGN Case series. SETTING Collaborative study in referral centers, institutional practice. PATIENTS A total of 690 hearing-impaired patients were genotypically and phenotypically described. The mutations of GJB2 and GJB6 were studied. Heterozygous patients were searched for another mutation by microsatellite approach. MAIN OUTCOME MEASURES Prevalence of GJB2 mutations, microsatellite approach, hearing-impairment. RESULTS In 498 patients (72,17% of the cohort), no mutation was found. Homozygotous patients were 59 (8,55%), with 51 for c.35delG, 6 for p.M34T and 2 for GJB6. Compound heterozygous were 64 (9,28%) with 56 c.35delG-others mutations. Genotypes with biallelic non sense mutations had a high risk of severe to profound hearing impairment. It was frequently milder in compound heterozygotes than in c.35delG homozygotes. Heterozygous patients were 69 (10%) with 21 c.35delG, 20 p.M34T and 28 others mutations. We selected patients with a complete historical medical file (clinical and audiometric data). Then, we performed a microsatellite approach (multiplex PCR of short DNA fragments) to localize a new pathologic allele. Seventeen heterozygous patients were studied. Six patients (35%) showed the same haplotype. They were compound heterozygous bearing a new pathologic allele. CONCLUSION Genotype may affect deafness severity, but environmental and other genetic factors may also modulate the severity and evolution of GJB2-GJB6 deafness. A new haplotype for GJB2 is described but the exact mutation remains unknown.
Collapse
Affiliation(s)
- Jean-Christophe Leclère
- Department of Otorhinolaryngology-Head and Neck Surgery, University Hospital CHU Brest, France
| | - Marie-Suzanne Le Gac
- Department of Otorhinolaryngology-Head and Neck Surgery, University Hospital CHU Brest, France
| | | | - Claude Ferec
- Genetic Department, University Hospital CHU Brest, France
| | - Rémi Marianowski
- Department of Otorhinolaryngology-Head and Neck Surgery, University Hospital CHU Brest, France.
| |
Collapse
|
10
|
Subaşıoğlu A, Duman D, Sırmacı A, Bademci G, Carkıt F, Somdaş MA, Erkan M, Tekin M, Dündar M. Research of genetic bases of hereditary non-syndromic hearing loss. Turk Arch Pediatr 2017; 52:122-132. [PMID: 29062245 DOI: 10.5152/turkpediatriars.2017.4254] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2016] [Accepted: 03/13/2017] [Indexed: 11/22/2022]
Abstract
AIM Hearing loss is the most common sensory disorder that affects approximately one per 1000 live births. With this project, we aimed to identify gene variants that were common causes of hearing loss in Turkey to contribute to the planning of genetic screening programs for hearing loss, as well as to improve genetic counseling to affected families. MATERIAL AND METHODS Twenty-one families with at least two affected individuals and parental consanguinity who presented with non-syndromic severe-to-profound sensorineural hearing loss were included in this study. We first screened for mutations in GJB2 and mitochondrial DNA 12S RNA genes. Subsequently, we genotyped the TMIE c.250C>T and SNP markers flanking the SLC26A4, MYO7A, MYO15A, OTOF, CDH23, TMIE, TECTA, PCDH15, TMC1, TMPRSS3, TMHS genes in the remaining twelve families without mutations in GJB2. RESULTS Screening for mutations in GJB2 gene showed c.[35delG];[35delG] mutation in four families, c.[35delG];[507C>A] mutation in two families, c.[35delG];[-23+1G>A] mutation in one family, and c.457G>A heterozygous mutation in one family. Genotyping SNP markers showed the c.[250C>T];[250C>T] mutation in TMIE in one family. A homozygous region with SNP genotypes was detected with the OTOF gene in one family, the TMPRSS3 gene in another family, and also a homozygous region was detected with TMHS, OTOF, and TMPRSS3 genes in another family. CONCLUSIONS Further research will be required to determine the genetic bases of hearing loss in families with non-syndromic hearing loss.
Collapse
Affiliation(s)
- Aslı Subaşıoğlu
- Department of Medical Genetics, Erciyes University Faculty of Medicine, Kayseri, Turkey
| | - Duygu Duman
- Department of Pediatrics, Division of Pediatric Genetic Diseases, Ankara University Faculty of Medicine, Ankara, Turkey
| | - Aslı Sırmacı
- Division of Human Genetics, John T. Macdonald, Miami University Miller Medical Faculty, Miami, USA
| | - Güney Bademci
- Division of Human Genetics, John T. Macdonald, Miami University Miller Medical Faculty, Miami, USA
| | - Fehime Carkıt
- Division of Odiology, Kayseri Education and Research Hospital, Kayseri, Turkey
| | - Mehmet Akif Somdaş
- Department of Otolaryngology, Erciyes University Faculty of Medicine, Kayseri, Turkey
| | - Mustafa Erkan
- Department of Otolaryngology, Erciyes University Faculty of Medicine, Kayseri, Turkey
| | - Mustafa Tekin
- Division of Human Genetics, John T. Macdonald, Miami University Miller Medical Faculty, Miami, USA
| | - Munis Dündar
- Department of Medical Genetics, Erciyes University Faculty of Medicine, Kayseri, Turkey
| |
Collapse
|
11
|
Stinckens C, Kremer H, van Wijk E, Hoefsloot LH, Huygen PLM, Standaert L, Fryns JP, Cremers CWRJ. Longitudinal Phenotypic Analysis in Patients with Connexin 26 (GJB2) (DFNB1) and Connexin 30 (GJB6) Mutations. Ann Otol Rhinol Laryngol 2016; 113:587-93. [PMID: 15274422 DOI: 10.1177/000348940411300714] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
In 15 Belgian subjects with prelingual sensorineural hearing impairment, the connexin 26 (GJB2) gene and the connexin 30 (GJB6) gene were analyzed for the presence of the 35delG mutation and the △( GJB6-D13S1830) deletion first described by del Castillo et al in 2002. Seven patients were found to be homozygous for the 35delG mutation; 7 were combined heterozygotes for the 35delG mutation and the GJB6 deletion. In 11 subjects, phenotype and genotype were correlated. Significant, transient progression, in the range of 1.7 to 2.7 dB/y, was only found in 2 patients in the first part of the second decade of life. Hearing impairment was otherwise stable, with mean thresholds of 75, 90, and 100 dB at 0.125, 0.25, and 0.5 kHz, respectively, and 100 dB or higher at 1 to 4 kHz. There was no significant difference in hearing impairment between the patients with the homozygous 35delG mutation in GJB2 and those who are heterozygous for both the 35delG mutation and the deletion encompassing part of GJB6.
Collapse
Affiliation(s)
- Christel Stinckens
- Department of Otorhinolaryngology, University Hospitals Leuven, Leuven, Belgium
| | | | | | | | | | | | | | | |
Collapse
|
12
|
Sanecka A, Biernacka EK, Sosna M, Mueller-Malesinska M, Ploski R, Skarzynski H, Piotrowicz R. Evaluation of electrocardiographic parameters in patients with hearing loss genotyped for the connexin 26 gene (GJB2) mutations. Braz J Otorhinolaryngol 2016; 83:176-182. [PMID: 27177978 PMCID: PMC9442716 DOI: 10.1016/j.bjorl.2016.02.008] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2015] [Revised: 02/22/2016] [Accepted: 02/28/2016] [Indexed: 11/17/2022] Open
Abstract
Introduction Several studies have associated congenital sensorineural hearing loss in children with prolongation of the cardiac parameter QTc. The cause of this association is unknown. At the same time, mutations in GJB2, which encodes connexin 26, are the most common cause of congenital hearing impairment. Objective To compare electrocardiographic parameters (PR interval, QRS complex, and QTc interval) in patients with hearing loss who were tested for mutations in GJB2 and GJB6 to investigate whether these mutations affect electrical activity of the heart. Methods 346 patients (176 males, 170 females) with sensorineural hearing loss of 30 dB HL or more, aged 21.8 ± 19.9 years (including 147 children <14 years), underwent both genetic study for GJB2 and GJB6 mutations and electrocardiography. Results Mutations in GJB2, including homozygotes and heterozygotes, were found in 112 (32%) patients. There were no significant differences in ECG parameters between groups of patients with and without mutations in GJB2. No differences were observed either in men (mean PR with mutation: 155 ± 16.6 vs. 153.6 ± 30.1 without; QRS: 99.9 ± 9.9 vs. 101.1 ± 15.4; QTc: 414.9 ± 29.9 vs. 412.4 ± 25.7) or women (mean PR with: 148.7 ± 21 vs. 143.8 ± 22.8 without; QRS: 94.8 ± 7.6 vs. 92.9 ± 9.6; QTc: 416.8 ± 20.6 vs. 424.9 ± 22.8). In similar fashion, we did we find any significant differences between groups of children with and without GJB2 mutations (mean PR with: 126.3 ± 19.6 vs. 127 ± 19.7 without; QRS: 80.7 ± 9.5 vs. 79.4 ± 11.6; QTc: 419.7 ± 23.5 vs. 419.8 ± 24.8). Conclusion No association was found between the presence of GJB2 mutations encoding connexin 26 in patients with hearing loss and their ECG parameters (PR, QRS, QTc).
Collapse
Affiliation(s)
| | | | - Magdalena Sosna
- Institute of Physiology and Pathology of Hearing, World Hearing Center, Nadarzyn, Poland
| | | | - Rafal Ploski
- Medical University of Warsaw, Department of Medical Genetics, Warsaw, Poland
| | - Henryk Skarzynski
- Institute of Physiology and Pathology of Hearing, World Hearing Center, Nadarzyn, Poland.
| | | |
Collapse
|
13
|
Dória M, Fernandes S, Moura CP. Study of Met34Thr variant in nonsyndromic hearing loss in four Portuguese families. Porto Biomed J 2016; 1:32-35. [PMID: 32258544 DOI: 10.1016/j.pbj.2015.07.001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2015] [Accepted: 07/28/2015] [Indexed: 10/21/2022] Open
Abstract
Objective The purpose of this work was to characterize the Met34Thr variant in a group of patients with nonsyndromic hearing loss, in order to establish a genotype-phenotype correlation. Methods 13 cases from 4 unrelated Portuguese families were selected, in which one or more hearing-impaired members had Met34Thr variant. Results Met34Thr variant was identified in 11/13 cases. Two cases have an additional mutation - Val153Ile and 35delG. Hearing loss was mild in 2 patients (Met34Thr/Val153Ile; Met34Thr/Met34Thr), moderate in 3(Met34Thr/WT; Met34Thr/35delG; Met34Thr/Met34Thr), severe in 2 (2 Met34Thr/WT) and profound in 1 (Met34Thr/WT). Three individuals with Met34Thr had normal hearing thresholds. Conclusion The present data corroborate the hypothesis that the Met34Thr variant is associated with mild-to-severe forms of deafness and that this variant seems to segregate with a dominant hearing loss with incomplete penetrance and a variable expression of the phenotype. However, other factors are likely to also have a pathologic effect.
Collapse
Affiliation(s)
- Mariana Dória
- Faculty of Medicine, University of Porto, Porto, Portugal
| | - Susana Fernandes
- Department of Human Genetics, Faculty of Medicine, University of Porto/São João Hospital Center, Porto, Portugal.,Institute for Research and Innovation in Health/Instituto de Investigação e Inovação em Saúde, University of Porto, Porto, Portugal
| | - Carla Pinto Moura
- Faculty of Medicine, University of Porto, Porto, Portugal.,Institute for Research and Innovation in Health/Instituto de Investigação e Inovação em Saúde, University of Porto, Porto, Portugal.,Department of Otorhinolaryngology and Department of Human Genetics, São João Hospital Center, Porto, Portugal
| |
Collapse
|
14
|
Reduced Connexin26 in the Mature Cochlea Increases Susceptibility to Noise-Induced Hearing Lossin Mice. Int J Mol Sci 2016; 17:301. [PMID: 26927086 PMCID: PMC4813165 DOI: 10.3390/ijms17030301] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2016] [Revised: 02/15/2016] [Accepted: 02/22/2016] [Indexed: 01/17/2023] Open
Abstract
Connexin26 (Cx26, encoded by GJB2) mutations are the most common cause of non-syndromic deafness. GJB2 is thought to be involved in noise-induced hearing loss (NIHL). However, the role of Cx26 in NIHL is still obscure. To explore the association between Cx26 and NIHL, we established a Cx26 knockdown (KD) mouse model by conditional knockdown of Cx26 at postnatal day 18 (P18), and then we observed the auditory threshold and morphologic changes in these mice with or without noise exposure. The Cx26 KD mice did not exhibit substantial hearing loss and hair cell degeneration, while the Cx26 KD mice with acoustic trauma experienced higher hearing loss than simple noise exposure siblings and nearly had no recovery. Additionally, extensive outer hair cell loss and more severe destruction of the basal organ of Corti were observed in Cx26 KD mice after noise exposure. These data indicate that reduced Cx26 expression in the mature mouse cochlea may increase susceptibility to noise-induced hearing loss and facilitate the cell degeneration in the organ of Corti.
Collapse
|
15
|
The pathological effects of connexin 26 variants related to hearing loss by in silico and in vitro analysis. Hum Genet 2016; 135:287-98. [PMID: 26749107 DOI: 10.1007/s00439-015-1625-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2015] [Accepted: 12/11/2015] [Indexed: 02/04/2023]
Abstract
Gap junctions (GJs) are intercellular channels associated with cell-cell communication. Connexin 26 (Cx26) encoded by the GJB2 gene forms GJs of the inner ear, and mutations of GJB2 cause congenital hearing loss that can be syndromic or non-syndromic. It is difficult to predict pathogenic effects using only genetic analysis. Using ionic and biochemical coupling tests, we evaluated the pathogenic effects of Cx26 variants using computational analyses to predict structural abnormalities. For seven out of ten variants, we predicted the variation would result in a loss of GJ function, whereas the others would completely fail to form GJs. Functional studies demonstrated that, although all variants were able to function normally as hetero-oligomeric GJ channels, six variants (p.E47K, p.E47Q, p.H100L, p.H100Y, p.R127L, and p.M195L) did not function normally as homo-oligomeric GJ channels. Interestingly, GJs composed of the Cx26 variant p.R127H were able to function normally, even as homo-oligomeric GJ channels. This study demonstrates the particular location and property of an amino acid are more important mainly than the domain where they belong in the formation and function of GJ, and will provide information that is useful for the accurate diagnosis of hearing loss.
Collapse
|
16
|
Lee MY, Takada T, Takada Y, Kappy MD, Beyer LA, Swiderski DL, Godin AL, Brewer S, King WM, Raphael Y. Mice with conditional deletion of Cx26 exhibit no vestibular phenotype despite secondary loss of Cx30 in the vestibular end organs. Hear Res 2015; 328:102-12. [PMID: 26232528 DOI: 10.1016/j.heares.2015.07.018] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/14/2015] [Revised: 07/22/2015] [Accepted: 07/23/2015] [Indexed: 01/19/2023]
Abstract
Connexins are components of gap junctions which facilitate transfer of small molecules between cells. One member of the connexin family, Connexin 26 (Cx26), is prevalent in gap junctions in sensory epithelia of the inner ear. Mutations of GJB2, the gene encoding Cx26, cause significant hearing loss in humans. The vestibular system, however, does not usually show significant functional deficits in humans with this mutation. Mouse models for loss of Cx26 function demonstrate hearing loss and cochlear pathology but the extent of vestibular dysfunction and organ pathology are less well characterized. To understand the vestibular effects of Cx26 mutations, we evaluated vestibular function and histology of the vestibular sensory epithelia in a conditional knockout (CKO) mouse with Cx26 loss of function. Transgenic C57BL/6 mice, in which cre-Sox10 drives excision of the Cx26 gene from non-sensory cells flanking the sensory epithelium of the inner ear (Gjb2-CKO), were compared to age-matched wild types. Animals were sacrificed at ages between 4 and 40 weeks and their cochlear and vestibular sensory organs harvested for histological examination. Cx26 immunoreactivity was prominent in the peripheral vestibular system and the cochlea of wild type mice, but absent in the Gjb2-CKO specimens. The hair cell population in the cochleae of the Gjb2-CKO mice was severely depleted but in the vestibular organs it was intact, despite absence of Cx26 expression. The vestibular organs appeared normal at the latest time point examined, 40 weeks. To determine whether compensation by another connexin explains survival of the normal vestibular sensory epithelium, we evaluated the presence of Cx30 in the Gjb2-CKO mouse. We found that Cx30 labeling was normal in the cochlea, but it was decreased or absent in the vestibular system. The vestibular phenotype of the mutants was not different from wild-types as determined by time on the rotarod, head stability tests and physiological responses to vestibular stimulation. Thus presence of Cx30 in the cochlea does not compensate for Cx26 loss, and the absence of both connexins from vestibular sensory epithelia is no more injurious than the absence of one of them. Further studies to uncover the physiological foundation for this difference between the cochlea and the vestibular organs may help in designing treatments for GJB2 mutations.
Collapse
Affiliation(s)
- Min Young Lee
- Kresge Hearing Research Institute, Department of Otolaryngology - Head and Neck Surgery, University of Michigan, 1150 West. Medical Center Dr., Ann Arbor, MI 48109-5648, USA
| | - Tomoko Takada
- Kresge Hearing Research Institute, Department of Otolaryngology - Head and Neck Surgery, University of Michigan, 1150 West. Medical Center Dr., Ann Arbor, MI 48109-5648, USA
| | - Yohei Takada
- Kresge Hearing Research Institute, Department of Otolaryngology - Head and Neck Surgery, University of Michigan, 1150 West. Medical Center Dr., Ann Arbor, MI 48109-5648, USA
| | - Michelle D Kappy
- Kresge Hearing Research Institute, Department of Otolaryngology - Head and Neck Surgery, University of Michigan, 1150 West. Medical Center Dr., Ann Arbor, MI 48109-5648, USA
| | - Lisa A Beyer
- Kresge Hearing Research Institute, Department of Otolaryngology - Head and Neck Surgery, University of Michigan, 1150 West. Medical Center Dr., Ann Arbor, MI 48109-5648, USA
| | - Donald L Swiderski
- Kresge Hearing Research Institute, Department of Otolaryngology - Head and Neck Surgery, University of Michigan, 1150 West. Medical Center Dr., Ann Arbor, MI 48109-5648, USA
| | - Ashley L Godin
- Kresge Hearing Research Institute, Department of Otolaryngology - Head and Neck Surgery, University of Michigan, 1150 West. Medical Center Dr., Ann Arbor, MI 48109-5648, USA
| | - Shannon Brewer
- Kresge Hearing Research Institute, Department of Otolaryngology - Head and Neck Surgery, University of Michigan, 1150 West. Medical Center Dr., Ann Arbor, MI 48109-5648, USA
| | - W Michael King
- Kresge Hearing Research Institute, Department of Otolaryngology - Head and Neck Surgery, University of Michigan, 1150 West. Medical Center Dr., Ann Arbor, MI 48109-5648, USA
| | - Yehoash Raphael
- Kresge Hearing Research Institute, Department of Otolaryngology - Head and Neck Surgery, University of Michigan, 1150 West. Medical Center Dr., Ann Arbor, MI 48109-5648, USA.
| |
Collapse
|
17
|
Yan D, Kannan-Sundhari A, Vishwanath S, Qing J, Mittal R, Kameswaran M, Liu XZ. The Genetic Basis of Nonsyndromic Hearing Loss in Indian and Pakistani Populations. Genet Test Mol Biomarkers 2015; 19:512-27. [PMID: 26186295 DOI: 10.1089/gtmb.2015.0023] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
Abstract
Deafness encompasses a series of etiologically heterogeneous disorders with mutations in more than 400 independent genes. However, several studies indicate that a large proportion of both syndromic and nonsyndromic forms of deafness in the racially diverse Indian and Pakistani populations are caused by defects in just a few genes. In these countries, there is a strong cultural preference for consanguineous marriage and an associated relatively high prevalence of genetic disorders. The current Indian population is approximately 1.2 billion and it is estimated that 30,000 infants are born with congenital sensorineural hearing loss (HL) each year. The estimated rate of profound bilateral HL is 1.6 per 1000 in Pakistan and 70% of this HL arises in consanguineous families. Knowledge of the genetic cause of deafness within a distinct population is important for accurate genetic counseling and early diagnosis for timely intervention and treatment options. Many sources and technologies are now available for the testing of hearing efficiency. Population-based screening has been proposed as one of the major strategies for translating genetic and genomic advances into population health gains. This review of the genetics of deafness in Indian and Pakistani populations deals with the major causes of deafness in these countries and prospectives for reducing the incidence of inherited deafness.
Collapse
Affiliation(s)
- Denise Yan
- 1 Departments of Otolaryngology-Head and Neck Surgery, Leonard M. Miller School of Medicine, University of Miami , Miami, Florida
| | - Abhiraami Kannan-Sundhari
- 1 Departments of Otolaryngology-Head and Neck Surgery, Leonard M. Miller School of Medicine, University of Miami , Miami, Florida.,2 SRM University , SRM Nagar, Chennai, India
| | - Subramanian Vishwanath
- 1 Departments of Otolaryngology-Head and Neck Surgery, Leonard M. Miller School of Medicine, University of Miami , Miami, Florida.,2 SRM University , SRM Nagar, Chennai, India
| | - Jie Qing
- 1 Departments of Otolaryngology-Head and Neck Surgery, Leonard M. Miller School of Medicine, University of Miami , Miami, Florida
| | - Rahul Mittal
- 1 Departments of Otolaryngology-Head and Neck Surgery, Leonard M. Miller School of Medicine, University of Miami , Miami, Florida
| | | | - Xue Zhong Liu
- 1 Departments of Otolaryngology-Head and Neck Surgery, Leonard M. Miller School of Medicine, University of Miami , Miami, Florida
| |
Collapse
|
18
|
Oonk AMM, Beynon AJ, Peters TA, Kunst HPM, Admiraal RJC, Kremer H, Verbist B, Pennings RJE. Vestibular function and temporal bone imaging in DFNB1. Hear Res 2015; 327:227-34. [PMID: 26188104 DOI: 10.1016/j.heares.2015.07.009] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/05/2015] [Revised: 06/30/2015] [Accepted: 07/12/2015] [Indexed: 10/23/2022]
Abstract
DFNB1 is the most prevalent type of hereditary hearing impairment known nowadays and the audiometric phenotype is very heterogeneous. There is, however, no consensus in literature on vestibular and imaging characteristics. Vestibular function and imaging results of 44 DFNB1 patients were evaluated in this retrospective study. All patients displayed a response during rotational velocity step testing. In 65% of the cases, the caloric results were within normal range bilaterally. The video head impulse test was normal in all patients. In 34.4% of the CT scans one or more temporal bone anomalies were found. The various anomalies found, were present in small numbers and none seemed convincingly linked to a specific DFNB1genotype. The group of DFNB1 patients presented here is the largest thus far evaluated for their vestibular function. From this study, it can be assumed that DFNB1 is not associated with vestibular dysfunction or specific temporal bone anomalies.
Collapse
Affiliation(s)
- A M M Oonk
- Department of Otorhinolaryngology, Hearing & Genes, Radboud University Medical Center, P.O. Box 9101, 6500 HB, Nijmegen, The Netherlands; Radboud Institute for Health Sciences, P.O. Box 9101, 6500 HB, Nijmegen, The Netherlands.
| | - A J Beynon
- Department of Otorhinolaryngology, Hearing & Genes, Radboud University Medical Center, P.O. Box 9101, 6500 HB, Nijmegen, The Netherlands; Radboud University Medical Center, Donders Institute for Brain, Cognition and Behaviour, P.O. Box 9101, 6500 HB, Nijmegen, The Netherlands
| | - T A Peters
- Department of Otorhinolaryngology, Hearing & Genes, Radboud University Medical Center, P.O. Box 9101, 6500 HB, Nijmegen, The Netherlands; Nijmegen Centre for Molecular Life Sciences, Radboud University Medical Center, P.O. Box 9101, 6500 HB, Nijmegen, The Netherlands
| | - H P M Kunst
- Department of Otorhinolaryngology, Hearing & Genes, Radboud University Medical Center, P.O. Box 9101, 6500 HB, Nijmegen, The Netherlands; Radboud Institute for Health Sciences, P.O. Box 9101, 6500 HB, Nijmegen, The Netherlands
| | - R J C Admiraal
- Department of Otorhinolaryngology, Hearing & Genes, Radboud University Medical Center, P.O. Box 9101, 6500 HB, Nijmegen, The Netherlands; Radboud University Medical Center, Donders Institute for Brain, Cognition and Behaviour, P.O. Box 9101, 6500 HB, Nijmegen, The Netherlands
| | - H Kremer
- Department of Otorhinolaryngology, Hearing & Genes, Radboud University Medical Center, P.O. Box 9101, 6500 HB, Nijmegen, The Netherlands; Nijmegen Centre for Molecular Life Sciences, Radboud University Medical Center, P.O. Box 9101, 6500 HB, Nijmegen, The Netherlands; Department of Human Genetics, Radboud University Medical Center, P.O. Box 9101, 6500 HB, Nijmegen, The Netherlands
| | - B Verbist
- Department of Radiology, Radboud University Medical Center, P.O. Box 9101, 6500 HB, Nijmegen, The Netherlands; Leiden University Medical Center, PO Box 9600, 2300 RC, Leiden, The Netherlands
| | - R J E Pennings
- Department of Otorhinolaryngology, Hearing & Genes, Radboud University Medical Center, P.O. Box 9101, 6500 HB, Nijmegen, The Netherlands; Radboud Institute for Health Sciences, P.O. Box 9101, 6500 HB, Nijmegen, The Netherlands
| |
Collapse
|
19
|
Kim SY, Kim AR, Han KH, Kim MY, Jeon EH, Koo JW, Oh SH, Choi BY. Residual Hearing in DFNB1 Deafness and Its Clinical Implication in a Korean Population. PLoS One 2015; 10:e0125416. [PMID: 26061264 PMCID: PMC4464755 DOI: 10.1371/journal.pone.0125416] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2014] [Accepted: 03/23/2015] [Indexed: 11/19/2022] Open
Abstract
Introduction The contribution of Gap junction beta-2 protein (GJB2) to the genetic load of deafness and its mutation spectra vary among different ethnic groups. Objective In this study, the mutation spectrum and audiologic features of patients with GJB2 mutations were evaluated with a specific focus on residual hearing. Methods An initial cohort of 588 subjects from 304 families with varying degrees of hearing loss were collected at the otolaryngology clinics of Seoul National University Hospital and Seoul National University Bundang Hospital from September 2010 through January 2014. GJB2 sequencing was carried out for 130 probands with sporadic or autosomal recessive non syndromic hearing loss. The audiograms were evaluated in the GJB2 mutants. Results Of the 130 subjects, 22 (16.9%) were found to carry at least one mutant allele of GJB2. The c.235delC mutation was shown to have the most common allele frequency (39.0%) among GJB2 mutations, followed by p.R143W (26.8%) and p.V37I (9.8%). Among those probands without the p.V37I allele in a trans configuration who showed some degree of residual hearing, the mean air conduction thresholds at 250 and 500 Hz were 57 dB HL and 77.8 dB HL, respectively. The c.235delC mutation showed a particularly wide spectrum of hearing loss, from mild to profound and significantly better hearing thresholds at 250 Hz and 2k Hz than in the non-p.V37I and non-235delC nonsyndromic hearing loss and deafness 1(DFNB1) subjects. Conclusion Despite its reputation as the cause of severe to profound deafness, c.235delC, the most frequent DFNB1 mutation in our cohort, caused a wide range of hearing loss with some residual hearing in low frequencies. This finding can be of paramount help for prediction of low frequency hearing thresholds in very young DFNB1 patients and highlights the importance of soft surgery for cochlear implantation in these patients.
Collapse
Affiliation(s)
- So Young Kim
- Department of Otorhinolaryngology-Head and Neck Surgery, Seoul National University Hospital, Seoul National University College of Medicine, Seoul, Korea
| | - Ah Reum Kim
- Department of Otorhinolaryngology-Head and Neck Surgery, Seoul National University Hospital, Seoul National University College of Medicine, Seoul, Korea
| | - Kyu Hee Han
- Department of Otorhinolaryngology-Head and Neck Surgery, National Medical Center, Seoul, Korea
| | - Min Young Kim
- Department of Otorhinolaryngology-Head and Neck Surgery, Seoul National University Bundang Hospital, Seoul National University College of Medicine, Seongnam, Korea
| | - Eun-Hee Jeon
- Department of Otorhinolaryngology-Head and Neck Surgery, Seoul National University Bundang Hospital, Seoul National University College of Medicine, Seongnam, Korea
| | - Ja-Won Koo
- Department of Otorhinolaryngology-Head and Neck Surgery, Seoul National University Bundang Hospital, Seoul National University College of Medicine, Seongnam, Korea
- Sensory Organ Research Institute, Seoul National University Medical Research Center, Seoul, Korea
| | - Seung Ha Oh
- Department of Otorhinolaryngology-Head and Neck Surgery, Seoul National University Hospital, Seoul National University College of Medicine, Seoul, Korea
- Sensory Organ Research Institute, Seoul National University Medical Research Center, Seoul, Korea
| | - Byung Yoon Choi
- Department of Otorhinolaryngology-Head and Neck Surgery, Seoul National University Bundang Hospital, Seoul National University College of Medicine, Seongnam, Korea
- Sensory Organ Research Institute, Seoul National University Medical Research Center, Seoul, Korea
- * E-mail:
| |
Collapse
|
20
|
Dahl JP, Stadler ME, Huang BY, Miao D, Patel MR, Adunka OF, Buchman CA, Fine JP, Zdanski CJ. Connexin-Related (DFNB1) Hearing Loss. Otolaryngol Head Neck Surg 2015; 152:889-96. [DOI: 10.1177/0194599814566399] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2014] [Accepted: 12/10/2014] [Indexed: 11/15/2022]
Abstract
Objectives Determine if routine computed tomography (CT) imaging is necessary in the workup for children with connexin-related (DFNB1) sensorineural hearing loss (SNHL). Study Design Case-control retrospective chart and imaging review. Setting Tertiary care otolaryngology practice. Subjects and Methods High-resolution temporal bone CT scans of children (n = 21) with DFNB1 SNHL were compared to age-matched controls with either conductive hearing loss (CHL, n = 33) or a nonsyndromic, non-DFNB1 SNHL (n = 33). Sixteen measurements of cochleo-vestibular structures were recorded. Statistical analysis was performed using a repeated analysis of variance model that controlled for both age and gender. Area under the curve (AUC) and multidimensional AUC (MAUC) analyses were also performed. Results Overall, no statistically significant differences were found between the 3 experimental groups. In addition, comparisons between the DFNB1 and CHL groups, DFNB1 and non-DFNB1 SNHL groups, and CHL and non-DFNB1 SNHL groups failed to demonstrate any statistically significant differences. AUC and MAUC analyses also failed to detect any significant differences between the 3 groups. Conclusions Patients with DFNB1 SNHL do not have significant anatomic differences on temporal bone CT scans when compared to non-DFNB1 SNHL and CHL control groups. Based on the above analysis, it is reasonable to avoid routine CT imaging of the temporal bones in children with known DFNB1 SNHL unless otherwise clinically indicated.
Collapse
Affiliation(s)
- John P. Dahl
- Department of Otolaryngology/Head and Neck Surgery, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Michael E. Stadler
- Department of Otolaryngology/Head and Neck Surgery, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Benjamin Y. Huang
- Department of Radiology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Di Miao
- Department of Biostatistics, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Mihir R. Patel
- Department of Otolaryngology/Head and Neck Surgery, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Oliver F. Adunka
- Department of Otolaryngology/Head and Neck Surgery, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Craig A. Buchman
- Department of Otolaryngology/Head and Neck Surgery, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Jason P. Fine
- Department of Biostatistics, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Carlton J. Zdanski
- Department of Otolaryngology/Head and Neck Surgery, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| |
Collapse
|
21
|
Cai Q, Wang B, Coling D, Zuo J, Fang J, Yang S, Vera K, Hu BH. Reduction in noise-induced functional loss of the cochleae in mice with pre-existing cochlear dysfunction due to genetic interference of prestin. PLoS One 2014; 9:e113990. [PMID: 25486270 PMCID: PMC4259315 DOI: 10.1371/journal.pone.0113990] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2014] [Accepted: 11/02/2014] [Indexed: 11/18/2022] Open
Abstract
Various cochlear pathologies, such as acoustic trauma, ototoxicity and age-related degeneration, cause hearing loss. These pre-existing hearing losses can alter cochlear responses to subsequent acoustic overstimulation. So far, the knowledge on the impacts of pre-existing hearing loss caused by genetic alteration of cochlear genes is limited. Prestin is the motor protein expressed exclusively in outer hair cells in the mammalian cochlea. This motor protein contributes to outer hair cell motility. At present, it is not clear how the interference of prestin function affects cochlear responses to acoustic overstimulation. To address this question, a genetic model of prestin dysfunction in mice was created by inserting an internal ribosome entry site (IRES)-CreERT2-FRT-Neo-FRT cassette into the prestin locus after the stop codon. Homozygous mice exhibit a threshold elevation of auditory brainstem responses with large individual variation. These mice also display a threshold elevation and a shift of the input/output function of the distortion product otoacoustic emission, suggesting a reduction in outer hair cell function. The disruption of prestin function reduces the threshold shifts caused by exposure to a loud noise at 120 dB (sound pressure level) for 1 h. This reduction is positively correlated with the level of pre-noise cochlear dysfunction and is accompanied by a reduced change in Cdh1 expression, suggesting a reduction in molecular responses to the acoustic overstimulation. Together, these results suggest that prestin interference reduces cochlear stress responses to acoustic overstimulation.
Collapse
Affiliation(s)
- Qunfeng Cai
- Center for Hearing and Deafness, University at Buffalo, Buffalo, New York, United States of America
| | - Bo Wang
- Department of Otolaryngology and Head & Neck Surgery, Institute of Otolaryngology, Chinese PLA General Hospital, Beijing, China
| | - Donald Coling
- Center for Hearing and Deafness, University at Buffalo, Buffalo, New York, United States of America
| | - Jian Zuo
- Developmental Neurobiology, St. Jude Children's Research Hospital, Memphis, Tennessee, United States of America
| | - Jie Fang
- Developmental Neurobiology, St. Jude Children's Research Hospital, Memphis, Tennessee, United States of America
| | - Shiming Yang
- Department of Otolaryngology and Head & Neck Surgery, Institute of Otolaryngology, Chinese PLA General Hospital, Beijing, China
| | - Krystal Vera
- Center for Hearing and Deafness, University at Buffalo, Buffalo, New York, United States of America
| | - Bo Hua Hu
- Center for Hearing and Deafness, University at Buffalo, Buffalo, New York, United States of America
- * E-mail:
| |
Collapse
|
22
|
Kelly JJ, Simek J, Laird DW. Mechanisms linking connexin mutations to human diseases. Cell Tissue Res 2014; 360:701-21. [DOI: 10.1007/s00441-014-2024-4] [Citation(s) in RCA: 61] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2014] [Accepted: 09/26/2014] [Indexed: 11/30/2022]
|
23
|
Zhu Y, Chen J, Liang C, Zong L, Chen J, Jones RO, Zhao HB. Connexin26 (GJB2) deficiency reduces active cochlear amplification leading to late-onset hearing loss. Neuroscience 2014; 284:719-729. [PMID: 25451287 DOI: 10.1016/j.neuroscience.2014.10.061] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2014] [Revised: 10/21/2014] [Accepted: 10/26/2014] [Indexed: 12/21/2022]
Abstract
Connexin26 (Cx26, GJB2) mutations account for >50% of nonsyndromic hearing loss. The deafness is not always congenital. A large group of these patients (∼30%) demonstrate a late-onset hearing loss, starting in childhood. They have normal hearing early in life and are therefore good candidates for applying protective and therapeutic interventions. However, the underlying deafness mechanism is unclear. In this study, we used a time-controlled, inducible gene knockout technique to knockout Cx26 expression in the cochlea after birth. We found that deletion of Cx26 after postnatal day 5 (P5) in mice could lead to late-onset hearing loss. Similar to clinical observations, the mice demonstrated progressive, mild to moderate hearing loss. The hearing loss initiated at high frequencies and then extended to the middle- and low-frequency range. The cochlea showed normal development and had no apparent hair cell loss. However, distortion product otoacoustic emission (DPOAE) was reduced. The reduction was also progressive and large at high-frequencies. Consistent with DPOAE reduction, we found that outer hair cell electromotility-associated nonlinear capacitance was shifted to the right and the slope of voltage dependence was reduced. The endocochlear potential was reduced in Cx26 conditional knockout (cKO) mice but the reduction was not associated with progressive hearing loss. These data suggest that Cx26 deficiency may impair active cochlear amplification leading to late-onset hearing loss. Our study also helps develop newer protective and therapeutic interventions to this common nonsyndromic hearing loss.
Collapse
Affiliation(s)
- Y Zhu
- Dept. of Otolaryngology, University of Kentucky Medical School, Lexington, KY 40536, United States
| | - J Chen
- Dept. of Otolaryngology, University of Kentucky Medical School, Lexington, KY 40536, United States
| | - C Liang
- Dept. of Otolaryngology, University of Kentucky Medical School, Lexington, KY 40536, United States
| | - L Zong
- Dept. of Otolaryngology, University of Kentucky Medical School, Lexington, KY 40536, United States
| | - J Chen
- Dept. of Otolaryngology, University of Kentucky Medical School, Lexington, KY 40536, United States
| | - R O Jones
- Dept. of Otolaryngology, University of Kentucky Medical School, Lexington, KY 40536, United States
| | - H-B Zhao
- Dept. of Otolaryngology, University of Kentucky Medical School, Lexington, KY 40536, United States.
| |
Collapse
|
24
|
|
25
|
Al-Sebeih K, Al-Kandari M, Al-Awadi SA, Hegazy FF, Al-Khamees GA, Naguib KK, Al-Dabbous RM. Connexin 26 gene mutations in non-syndromic hearing loss among Kuwaiti patients. Med Princ Pract 2014; 23:74-9. [PMID: 24080506 PMCID: PMC5586821 DOI: 10.1159/000348304] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/11/2013] [Accepted: 01/22/2013] [Indexed: 11/19/2022] Open
Abstract
OBJECTIVE To study connexin 26 (Cx26) gene mutations among autosomal recessive non-syndromal hearing loss in Kuwaiti patients and evaluate their effect on phenotypes. SUBJECTS AND METHODS This cross sectional study included 100 patients aged between 6 months and 18 years, who were referred to the Sheikh Salem Al-Ali Centre for audiology and speech evaluation of autosomal recessive non-syndromic sensorineural hearing loss confirmed by clinico-genetic evaluation and a battery of diagnostic tests. Gene profiling and sequencing were performed to detect the presence and nature of Cx26 mutation. RESULTS Of the 100 patients, mutation of Cx26 gene was detected in 15 patients (15%) of which 9 (60%) cases were heterozygous and 6 cases (40%) were homozygous. Eighty per cent of the 15 Cx26 positive cases resulted from the 35delG mutation. Among the heterozygous cases, 6 (66.6%) were positive for 35delG. All 6 homozygous patients were positive for the 35delG mutation. A significant correlation was found between genetic findings (p = 0.013) and family history (p = 0.029), as well as the onset (p = 0.015), course (p = 0.033), degree and configuration of hearing loss (p = 0.001). CONCLUSION Among the selected Kuwaiti population sample, the Cx26 gene mutation was responsible for 15% of autosomal recessive non-syndromic sensorineural hearing loss. We recommend that screening for Cx26 gene mutation be considered in the screening strategy of patients with non-syndromic childhood hearing loss for counselling and management purposes. .
Collapse
Affiliation(s)
- Khalid Al-Sebeih
- Department of Surgery, Faculty of Medicine, Health Science Center, Kuwait University, Kuwait City, Kuwait
- Department of Otolaryngology, Zain Hospital, Kuwait City, Kuwait
- *Khalid H. Al-Sebeih, MD, FRCSC, FACS, Department of Surgery – Otolaryngology Division, Faculty of Medicine, Kuwait University, PO Box 17228 Khalidiya, 72453 Kuwait City (Kuwait), E-Mail
| | | | | | - Fatma F. Hegazy
- Kuwait Medical Genetics Centre, Sabah Hospital, Kuwait City, Kuwait
| | | | | | | |
Collapse
|
26
|
Wei Q, Liu Y, Wang S, Liu T, Lu Y, Xing G, Cao X. A novel compound heterozygous mutation in the GJB2 gene causing non-syndromic hearing loss in a family. Int J Mol Med 2013; 33:310-6. [PMID: 24337325 PMCID: PMC3896467 DOI: 10.3892/ijmm.2013.1581] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2013] [Accepted: 12/03/2013] [Indexed: 11/23/2022] Open
Abstract
Mutations in the GJB2 gene are responsible for up to 50% of cases of non-syndromic recessive hearing loss, with c.35delG, c.167delT and c.235delC being the predominant mutations in many world populations. However, a large number of rare mutations in this gene may also contribute to hearing loss. The aim of the present study was to conduct a clinical and molecular characterization of a Chinese family with non-syndromic hearing loss. Sequence analysis of the GJB2 gene led to the identification of a novel compound heterozygous mutation c.257C>G (p.T86R)/c.605ins46 in two profoundly deaf siblings whose hearing parents were each heterozygous, either for the c.257C>G (paternal) or for the c.605ins46 (maternal) mutations. Both c.257C>G and c.605ins46 are rare GJB2 mutations that have previously been reported to segregate with autosomal recessive hearing loss exclusively in East Asian populations. To study the pathogenic effect of the compound heterozygous mutation, a three-dimensional model was constructed and Anolea mean force potential energy was predicted for a bioinformatic structural analysis. HEK293 cells were used to study the pathogenic effect of mutant connexin 26 proteins. The results suggested that the c.257C>G (p.T86R)/c.605ins46 mutations in the GJB2 gene provides a novel molecular explanation for the role of the GJB2 gene in hearing loss.
Collapse
Affiliation(s)
- Qinjun Wei
- Department of Biotechnology, School of Basic Medical Sciences, Nanjing Medical University, Nanjing, Jiangsu 210029, P.R. China
| | - Youguo Liu
- Department of Otolaryngology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu 210029, P.R. China
| | - Shuai Wang
- Department of Biotechnology, School of Basic Medical Sciences, Nanjing Medical University, Nanjing, Jiangsu 210029, P.R. China
| | - Tingting Liu
- Department of Otolaryngology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu 210029, P.R. China
| | - Yajie Lu
- Department of Biotechnology, School of Basic Medical Sciences, Nanjing Medical University, Nanjing, Jiangsu 210029, P.R. China
| | - Guangqian Xing
- Department of Otolaryngology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu 210029, P.R. China
| | - Xin Cao
- Department of Biotechnology, School of Basic Medical Sciences, Nanjing Medical University, Nanjing, Jiangsu 210029, P.R. China
| |
Collapse
|
27
|
Davoudi-Dehaghani E, Fallah MS, Shirzad T, Tavakkoly-Bazzaz J, Bagherian H, Zeinali S. Reporting the presence of three different diseases causingGJB2mutations in a consanguineous deaf family. Int J Audiol 2013; 53:128-31. [DOI: 10.3109/14992027.2013.850748] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
|
28
|
Chan DK, Chang KW. GJB2-associated hearing loss: Systematic review of worldwide prevalence, genotype, and auditory phenotype. Laryngoscope 2013; 124:E34-53. [DOI: 10.1002/lary.24332] [Citation(s) in RCA: 183] [Impact Index Per Article: 16.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/10/2013] [Indexed: 12/17/2022]
Affiliation(s)
- Dylan K. Chan
- Department of Otolaryngology-Head and Neck Surgery; University of California; San Francisco U.S.A
| | - Kay W. Chang
- Department of Otolaryngology-Head and Neck Surgery; Stanford University School of Medicine; Stanford California U.S.A
| |
Collapse
|
29
|
Esteves MCBN, de Lima Isaac M, Francisco AM, da Silva Junior WA, Ferreira CA, Dell'Aringa AHB. Analysis of the presence of the GJB6 mutations in patients heterozygous for GJB2 mutation in Brazil. Eur Arch Otorhinolaryngol 2013; 271:695-9. [PMID: 23553242 DOI: 10.1007/s00405-013-2468-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2012] [Accepted: 03/20/2013] [Indexed: 10/27/2022]
Abstract
Mutations in the GJB2 gene, mainly 35delG, are responsible for most autosomal recessive inherited genetic hearing loss. The audiometric standard of these hearing losses remains inconsistent and other genes, such as GJB6, have been involved in association with GJB2. The objective of the study was to identify the deletions del(GJB6-D13S1830) and del(GJB6-D13S1854) in patients heterozygous for 35delG/GJB2 and analyze the phenotype they present. 101 patients with mild to profound degree of sensorineural hypoacusis were evaluated. The allele-specific PCR technique was used to identify 35delG. The del(GJB6-D13S1830) and del(GJB6-D13S1854) were identified through the PCR multiplex technique. 90% of the subjects presented a normal genotype for the analyzed mutations; 6.93% were shown to be heterozygous for 35delG/GJB2 and 1% presented compound heterozygosis GJB2/GJB6). The data found reinforced the hypothesis of an interaction of more than one gene as the cause of autosomal recessive genetic hearing loss and emphasized the importance of an early diagnosis for appropriate intervention.
Collapse
|
30
|
Connexin 26 and 30 mutations in paediatric patients with congenital, non-syndromic hearing loss treated with cochlear implantation in Mediterranean Turkey. The Journal of Laryngology & Otology 2012; 127:33-7. [PMID: 23171692 DOI: 10.1017/s0022215112002587] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
AbstractObjective:Mutations in the genes for connexin 26 (GJB2) and connexin 30 (GJB6) play an important role in autosomal recessive, non-syndromic hearing loss. This study aimed to detect the 35delG and 167delT mutations of theGJB2gene and the del(GJB6-D13S1830) mutation of theGJB6gene in paediatric patients diagnosed with congenital, non-syndromic hearing loss and treated with cochlear implantation in Mediterranean Turkey.Materials and method:We included 94 children diagnosed with congenital, non-syndromic hearing loss and treated with cochlear implantation. Blood samples were collected, DNA extracted and an enzyme-linked immunosorbent assay performed to enable molecular diagnosis of mutations.Results:Of the 94 children analysed, the 35delG mutation was detected in 12 (12.7 per cent): 10 (83.3 per cent) were homozygous and 2 (16.7 per cent) heterozygous mutant. The 167delT and del(GJB6-D13S1830) mutations were not detected.Conclusion:The GJB2-35delG mutation is a major cause of congenital, non-syndromic hearing loss in this study population.
Collapse
|
31
|
Moussavi-Najarkola SA, Khavanin A, Mirzaei R, Salehnia M, Akbari M. Assessment of the influence of whole body vibration on Cochlear function. J Occup Med Toxicol 2012; 7:12. [PMID: 22720724 PMCID: PMC3480898 DOI: 10.1186/1745-6673-7-12] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2011] [Accepted: 05/04/2012] [Indexed: 02/02/2023] Open
Abstract
Background Whole body vibration (WBV) is a potentially harmful consequence resulting from the dissipation of energy by industrial machineries. The result of WBV exposure on the auditory system remains unknown. The objective of the present research was to evaluate the influence of WBV on cochlear function, in particular outer hair cell function. It is hypothesized that WBV impairs cochlear function resulting in decreased Distortion Product Otoacoustic Emission (DPOAE) levels (Ldp) in rabbits subjected to WBV. Methods Twelve rabbits were equally divided into vibration and control groups. Animals in vibration group were exposed to 1.0 ms-2 r.m.s vertical WBV at 4–8 Hz for 8 h/day during 5 consecutive days. Outer hair cell function was assessed by comparing repeated-measurements of DPOAE levels (Ldp) across a range of f2 frequencies in rabbits both exposed and unexposed to WBV. DPOAE level shifts (LSdp) were compared across ears, frequencies, groups, and times. Results No differences were seen over time in DPOAE levels in the non-exposed rabbits (p = 0.082). Post-exposure Ldp in rabbits exposed to WBV were significantly increased at all test frequencies in both ears compared to baseline measures (p = 0.021). The greatest increase in Ldp following exposure was seen at 5888.5 Hz (mean shift = 13.25 dB). Post-exposure Ldp in rabbits exposed to WBV were not significantly different between the right and left ears (p = 0.083). Conclusion WBV impairs cochlear function resulting in increased DPOAE responses in rabbits exposed to WBV. DPOAE level shifts occurred over a wide range of frequencies following prolonged WBV in rabbits.
Collapse
|
32
|
Li L, Lu J, Tao Z, Huang Q, Chai Y, Li X, Huang Z, Li Y, Xiang M, Yang J, Yao G, Wang Y, Yang T, Wu H. The p.V37I exclusive genotype of GJB2: a genetic risk-indicator of postnatal permanent childhood hearing impairment. PLoS One 2012; 7:e36621. [PMID: 22574200 PMCID: PMC3344898 DOI: 10.1371/journal.pone.0036621] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2012] [Accepted: 04/03/2012] [Indexed: 11/18/2022] Open
Abstract
Postnatal permanent childhood hearing impairment (PCHI) is frequent (0.25%-0.99%) and difficult to detect in the early stage, which may impede the speech, language and cognitive development of affected children. Genetic tests of common variants associated with postnatal PCHI in newborns may provide an efficient way to identify those at risk. In this study, we detected a strong association of the p.V37I exclusive genotype of GJB2 with postnatal PCHI in Chinese Hans (P = 1.4×10(-10); OR 62.92, 95% CI 21.27-186.12). This common genotype in Eastern Asians was present in a substantial percentage (20%) of postnatal PCHI subjects, and its prevalence was significantly increased in normal-hearing newborns who failed at least one newborn hearing screen. Our results indicated that the p.V37I exclusive genotype of GJB2 may cause subclinical hearing impairment at birth and increases risk for postnatal PCHI. Genetic testing of GJB2 in East Asian newborns will facilitate prompt detection and intervention of postnatal PCHI.
Collapse
Affiliation(s)
- Lei Li
- Department of Otolaryngology–Head and Neck Surgery, Xinhua Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China
- Ear Institute, Shanghai Jiaotong University, Shanghai, China
| | - Jingrong Lu
- Department of Otolaryngology–Head and Neck Surgery, Xinhua Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China
- Ear Institute, Shanghai Jiaotong University, Shanghai, China
| | - Zheng Tao
- Ear Institute, Shanghai Jiaotong University, Shanghai, China
- Shanghai Children's Medical Center, Shanghai, China
| | - Qi Huang
- Department of Otolaryngology–Head and Neck Surgery, Xinhua Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China
- Ear Institute, Shanghai Jiaotong University, Shanghai, China
| | - Yongchuan Chai
- Department of Otolaryngology–Head and Neck Surgery, Xinhua Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China
- Ear Institute, Shanghai Jiaotong University, Shanghai, China
| | - Xiaohua Li
- Department of Otolaryngology–Head and Neck Surgery, Xinhua Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China
- Ear Institute, Shanghai Jiaotong University, Shanghai, China
| | - Zhiwu Huang
- Department of Otolaryngology–Head and Neck Surgery, Xinhua Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China
- Ear Institute, Shanghai Jiaotong University, Shanghai, China
| | - Yun Li
- Department of Otolaryngology–Head and Neck Surgery, Xinhua Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China
- Ear Institute, Shanghai Jiaotong University, Shanghai, China
| | - Mingliang Xiang
- Department of Otolaryngology–Head and Neck Surgery, Xinhua Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China
- Ear Institute, Shanghai Jiaotong University, Shanghai, China
| | - Jun Yang
- Department of Otolaryngology–Head and Neck Surgery, Xinhua Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China
- Ear Institute, Shanghai Jiaotong University, Shanghai, China
| | - Guoyin Yao
- Shanghai Child Health Care Institute, Shanghai, China
| | - Yu Wang
- Shanghai Child Health Care Institute, Shanghai, China
| | - Tao Yang
- Department of Otolaryngology–Head and Neck Surgery, Xinhua Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China
- Ear Institute, Shanghai Jiaotong University, Shanghai, China
- * E-mail: (HW); (TY)
| | - Hao Wu
- Department of Otolaryngology–Head and Neck Surgery, Xinhua Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China
- Ear Institute, Shanghai Jiaotong University, Shanghai, China
- * E-mail: (HW); (TY)
| |
Collapse
|
33
|
Dodson KM, Blanton SH, Welch KO, Norris VW, Nuzzo RL, Wegelin JA, Marin RS, Nance WE, Pandya A, Arnos KS. Vestibular dysfunction in DFNB1 deafness. Am J Med Genet A 2011; 155A:993-1000. [PMID: 21465647 DOI: 10.1002/ajmg.a.33828] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2010] [Accepted: 11/01/2010] [Indexed: 11/07/2022]
Abstract
Mutations of GJB2 and GJB6 (connexin-26 and 30) at the DFNB1 locus are the most common cause of autosomal recessive, nonsyndromic deafness. Despite their widespread expression throughout the vestibular system, vestibular dysfunction has not been widely recognized as a commonly associated clinical feature. The observations of vertigo accompanying DFNB1 deafness in several large families prompted our hypothesis that vestibular dysfunction may be an integral, but often overlooked, component of DFNB1 deafness. Our aim was to define the prevalence of vestibular dysfunction in Cases of DFNB1 deafness and Controls with other forms of deafness. We developed and used a survey to assess symptoms of vestibular dysfunction, medical, and family history was distributed to Cases with deafness due to pathogenic GJB2 and/or GJB6 mutations and deaf Controls without DFNB1 deafness. Our results showed: Surveys were returned by 235/515 Cases (46%) with DFNB1 mutations and 121/321 Controls (38%) without these mutations. The mean age of Cases (41) was younger than Controls (51; P < 0.001). Vestibular dysfunction was reported by 127 (54%) of Cases and was present at significantly higher rates in Cases than in deaf Controls without DFNB1 deafness (P < 0.03). Most (63%) had to lie down in order for vertigo to subside, and 48% reported that vertigo interfered with activities of daily living. Vertigo was reported by significantly more Cases with truncating than non-truncating mutations and was also associated with a family history of dizziness. We conclude that vestibular dysfunction appears to be more common in DFNB1 deafness than previously recognized and affects activities of daily living in many patients.
Collapse
Affiliation(s)
- Kelley M Dodson
- Department of Otolaryngology, Virginia Commonwealth University, Richmond, USA.
| | | | | | | | | | | | | | | | | | | |
Collapse
|
34
|
Kenna MA, Rehm HL, Frangulov A, Feldman HA, Robson CD. Temporal bone abnormalities in children with GJB2 mutations. Laryngoscope 2011; 121:630-5. [PMID: 21298644 DOI: 10.1002/lary.21414] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2010] [Accepted: 10/23/2010] [Indexed: 11/08/2022]
Abstract
OBJECTIVES To determine the incidence of temporal bone abnormalities in children with sensorineural hearing loss (SNHL) and pathogenic biallelic GJB2 mutations. STUDY DESIGN Retrospective analysis of a large cohort of pediatric patients with biallelic GJB2 mutations and SNHL (observational case series). METHODS Blinded review of all available temporal bone computed tomographic (CT) and magnetic resonance imaging (MRI) studies in this cohort. RESULTS Out of 158 patients with biallelic GJB2 mutations, 113 had CT and/or MRI studies available for review. Definite, although generally subtle, inner ear abnormalities were present in 12/113. There were malformations of the semicircular canals (SCC) in 4/12, of the internal auditory canal in 2/12, of the cochlear nerve canal (CNC) in 6, and unilateral cochlear malformation in 1/12. MRI in 1/5 showed mildly hypoplastic cochlear nerve. There was no correlation between SNHL severity and presence/absence/type of malformations or genotype. CONCLUSIONS Our study of 113 biallelic GJB2 patients with SNHL and temporal bone imaging is the largest study to date. We found only 10% had any abnormalities, most subtle, and none had EVA. Additionally, there was no correlation between SNHL severity and presence/absence/type of malformations or genotype. Disparities between our group and previous reports may be due to differences in degree of hearing loss, types of mutations, populations studied, and radiologic factors for both image acquisition and interpretation.
Collapse
Affiliation(s)
- Margaret A Kenna
- Department of Otolaryngology and Communication Enhancement, Children's Hospital Boston, Boston, Massachusetts, USA.
| | | | | | | | | |
Collapse
|
35
|
The genetic basis of auditory neuropathy spectrum disorder (ANSD). Int J Pediatr Otorhinolaryngol 2011; 75:151-8. [PMID: 21176974 DOI: 10.1016/j.ijporl.2010.11.023] [Citation(s) in RCA: 81] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/13/2010] [Revised: 11/24/2010] [Accepted: 11/24/2010] [Indexed: 11/21/2022]
Abstract
OBJECTIVE Auditory neuropathy is a hearing disorder where outer hair cell function within the cochlea is normal, but inner hair cell and/or the auditory nerve function is disrupted. It is a heterogeneous disorder which can have either congenital or acquired causes. Furthermore, the aetiology of auditory neuropathy is vast, which may include prematurity, hyperbilirubinaemia, anoxia, hypoxia, congenital brain anomalies, ototoxic drug exposure, and genetic factors. It is estimated that approximately 40% of cases have an underlying genetic basis, which can be inherited in both syndromic and non syndromic conditions. This review paper provides an overview of the genetic conditions associated with auditory neuropathy spectrum disorders (ANSDs) and highlights some of the defective genes that have been found to be linked to the pathological auditory changes. METHOD Literature search was conducted using a number of resources including textbooks, professional journals and the relevant websites. RESULTS The largest proportion of auditory neuropathy spectrum disorders (ANSDs) is due to genetic factors which can be syndromic, non-syndromic or mitochondrial related. The inheritance pattern can include all the four main types of inheritances such as autosomal dominant, autosomal recessive, X-linked and mitochondrial. CONCLUSION This paper has provided an overview of mutation with some of the genes and/or loci discovered to be the cause for auditory neuropathy spectrum disorders (ANSDs). It has been noted that different gene mutations may trigger different pathological changes in patients with this disorder. These discoveries have provided us with vital information as to the sites of pathology in auditory neuropathy spectrum disorders (ANSDs), and the results highlight the heterogeneity of the disorder.
Collapse
|
36
|
Löppönen T, Väisänen ML, Luotonen M, Allinen M, Uusimaa J, Lindholm P, Mäki-Torkko E, Väyrynen M, Löppönen H, Leisti J. Connexin 26 mutations and nonsyndromic hearing impairment in Northern Finland. Laryngoscope 2010; 113:1758-63. [PMID: 14520102 DOI: 10.1097/00005537-200310000-00018] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
OBJECTIVE The aims of the present study were to evaluate the role of the gap junction protein beta-2 gene (GJB2), encoding connexin 26 (Cx26), in children with moderate to profound prelingual nonsyndromic sensorineural hearing impairment (HI) and to investigate the carrier frequencies of the GJB2 gene mutations in a control population in Northern Finland. METHODS Mutation analysis was performed by direct sequencing and carrier detection by conformation sensitive gel electrophoresis further confirmed by direct sequencing. RESULTS Cx26 mutations were found in 15 of 71 (21.1%) (67 families) children with HI. Homozygosity for the mutation 35delG was shown to be the cause of HI in 13 of 15 (86.7%) children. Homozygosity for the M34T genotype was found in one child, and compound heterozygosity for the M34T/V37I genotype was found in another. Five families of those with suspected familial HI (29.4%) and six families out of those with sporadic HI (12.0%) had a homozygous or compound heterozygous mutation. The carrier frequency for the mutation 35delG was 1 of 78 (4 of 313) and that for the M34T was 1 of 26 (12 of 313). CONCLUSION 35delG/35delG genotype was found to be a significant cause of moderate to profound prelingual nonsyndromic sensorineural HI in Northern Finland. M34T/M34T genotype was seen in only one child, but the carrier frequency of the M34T allele was about three times higher than that of the 35delG mutation.
Collapse
Affiliation(s)
- Tuija Löppönen
- Department of Clinical Genetics, Oulu University Hospital, Kajaanintie 50, FIN-90220 Oulu, Finland.
| | | | | | | | | | | | | | | | | | | |
Collapse
|
37
|
Kokotas H, Grigoriadou M, Hatzaki A, Antoniadi T, Giannoulia-Karantana A, Petersen MB. Easy, rapid, and cost-effective methods for identifying carriers of recurrent GJB2 mutations causing nonsyndromic hearing impairment in the Greek population. Genet Test Mol Biomarkers 2010; 14:189-92. [PMID: 20059378 DOI: 10.1089/gtmb.2009.0136] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
A variety of techniques have been developed for screening the GJB2 gene for known and unknown mutations, especially the most common mutation in the Caucasian population, the c.35delG. Other mutations that have been so far characterized in the GJB2 gene seem to have different geographical distributions, and therefore there is an interest in identifying recurrent mutations specific for each population and developing easy and rapid screening techniques. Here we present easy screening protocols for already identified recurrent mutations in the Greek population. Developing easy, rapid, and cost-effective screening methods will facilitate the detection of GJB2 recurrent mutation carriers, at large, in the Greek population.
Collapse
Affiliation(s)
- Haris Kokotas
- Department of Genetics, Institute of Child Health, Aghia Sophia Children's Hospital, Athens, Greece.
| | | | | | | | | | | |
Collapse
|
38
|
Shan J, Chobot-Rodd J, Castellanos R, Babcock M, Shanske A, Parikh SR, Morrow BE, Samanich J. GJB2 mutation spectrum in 209 hearing impaired individuals of predominantly Caribbean Hispanic and African descent. Int J Pediatr Otorhinolaryngol 2010; 74:611-8. [PMID: 20381175 DOI: 10.1016/j.ijporl.2010.03.004] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/25/2009] [Revised: 02/24/2010] [Accepted: 03/01/2010] [Indexed: 11/29/2022]
Abstract
OBJECTIVE The purpose of the study is to determine whether Caribbean Hispanic and African admixture populations have a paucity of mutations in GJB2, encoding connexin 26. METHODS We reported the paucity of mutations in GJB2 and deletions in GJB6 in Caribbean Hispanic and African admixture populations in the Bronx, NY, in 2007 [1]. We have now collected 102 additional probands with non-syndromic sensorineural hearing impairment (NSHI), for a total of 209. We describe here a presentation of the combined data. RESULTS Of the 209 probands, 36% have affected family members with NSHI and the rest have sporadic occurrence. Of the familial cases, 43% had a first-degree relative affected, and the remainder a more distant relative. The hearing impairment ranged from unilateral mild to bilateral profound, with 76% exhibiting bilateral NSHI (BLNSHI). The single coding exon of the GJB2 gene was sequenced in 209 probands, PCR screening for del(GJB6-D13S1830) and sequencing of the non-coding exon of GJB2 to look for the known splice site mutation was performed in 32 NSHI patients with a heterozygous variation in GJB2, and multiplex ligation-dependent probe amplification (MLPA) testing of GJB2 and GJB6 exon deletions or amplifications (P163 GJB-WFS1 kit) was done in 70 probands. Eight unrelated individuals had biallelic GJB2 mutations, representing 4% of our entire cohort, or 5% of our probands with BLNSHI. Of 127 probands of Hispanic or African descent with BLNSHI, six (4.7%) had biallelic pathogenic mutations, three (2.3%) had monoallelic mutations and 118 (93%) had no disease-causing mutations in GJB2. At the same time, no major deletions were identified either by PCR screening (del(GJB6-D13S1830)) or by MLPA analysis (GJB2 or GJB6), and no subjects had the known splice site mutation in GJB2. CONCLUSION These results demonstrate that GJB2 is not the major contributor to the genetic basis of NSHI for the Bronx minority admixture populations.
Collapse
Affiliation(s)
- Jidong Shan
- Department of Genetics, Albert Einstein College of Medicine, 1301 Morris Park Avenue, Bronx, NY 10461, United States
| | | | | | | | | | | | | | | |
Collapse
|
39
|
Yan D, Liu XZ. Modifiers of hearing impairment in humans and mice. Curr Genomics 2010; 11:269-78. [PMID: 21119891 PMCID: PMC2930666 DOI: 10.2174/138920210791233054] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2010] [Revised: 04/03/2010] [Accepted: 04/07/2010] [Indexed: 02/04/2023] Open
Abstract
Lack of penetrance and variability of expression are common findings in nonsyndromic hearing loss with autosomal dominant mode of inheritance, but are also seen with recessive inheritance. Now we know that genotype cannot necessarily predict phenotype due to the complexity of the genome, the proteome interacting with the transcriptome, and the dynamically coupled systems that are involved. The contribution of genetic background to phenotypic diversity reflects the additive and interactive (epistasis) effects of multiple genes. Because, individual genes do not act alone but rather in concert with many other genes, it is not surprising that, modifier genes are common source of phenotypic variation in human populations. They can affect the phenotypic outcome of a given genotype by interacting in the same or in a parallel biological pathway as the disease gene. These modifier genes modulate penetrance, dominance, pleiotropy or expressivity in individuals with Mendelian traits and can also be exerted by influencing the severity, the penetrance, the age of onset and the progression of a disease. In this review, we focus on modifier genes that specifically affect hearing loss phenotypes in humans as well as those described in mice. We also include examples of digenic inheritance of deafness, because additive or interactive effects can also result from interaction between two mutant genes.
Collapse
Affiliation(s)
| | - Xue-Zhong Liu
- Department of Otolaryngology, Miller School of Medicine, University of Miami, Miami, FL 33136, USA
| |
Collapse
|
40
|
Kokotas H, Grigoriadou M, Korres GS, Ferekidou E, Giannoulia-Karantana A, Kandiloros D, Korres S, Petersen MB. Are GJB2 mutations an aggravating factor in the phenotypic expression of mitochondrial non-syndromic deafness? J Hum Genet 2010; 55:265-9. [DOI: 10.1038/jhg.2010.23] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
|
41
|
Kenna MA, Feldman HA, Neault MW, Frangulov A, Wu BL, Fligor B, Rehm HL. Audiologic phenotype and progression in GJB2 (Connexin 26) hearing loss. ACTA ACUST UNITED AC 2010; 136:81-7. [PMID: 20083784 DOI: 10.1001/archoto.2009.202] [Citation(s) in RCA: 69] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
OBJECTIVES To document the audiologic phenotype of children with biallelic GJB2 (connexin 26) mutations, and to correlate it with the genotype. DESIGN Prospective, observational study. SETTING Tertiary care children's hospital. PATIENTS Infants and children with sensorineural hearing loss (SNHL). INTERVENTION Sequencing of the GJB2 (connexin 26) gene. MAIN OUTCOME MEASURES Degree and progression of SNHL. RESULTS From December 1, 1998, through November 30, 2006, 126 children with biallelic GJB2 mutations were identified. Of the 30 different mutations identified, 13 (43%) were truncating and 17 (57%) were nontruncating; 62 patients had 2 truncating, 30 had 1 truncating and 1 nontruncating, and 17 had 2 nontruncating mutations. Eighty-four patients (67%) initially had measurable hearing in the mild to severe range in at least 1 of 4 frequencies (500, 1000, 2000, or 4000 Hz). Of these 84 patients with residual hearing, 47 (56%) had some degree of progressive hearing loss. Patients with 2 truncating mutations had significantly worse hearing compared with all other groups. Patients who had 1 or 2 copies of either an M34T or a V37I allele had the mildest hearing loss. CONCLUSIONS Hearing loss owing to GJB2 mutations ranges from mild to profound and is usually congenital. More than 50% of patients will experience some hearing loss progression, generally gradually but occasionally precipitously. Hearing loss severity may be influenced by genetic factors, such as the degree of preserved protein function in nontruncating mutations, whereas hearing loss progression may be dependent on factors other than the connexin 26 protein. Genetic counseling for patients with GJB2 mutations should include the variable audiologic phenotype and the possibility of progression.
Collapse
Affiliation(s)
- Margaret A Kenna
- Department of Otolaryngology and Communication Enhancement, Children's Hospital Boston, 300 Longwood Ave, LO-367, Boston, MA 02115, USA.
| | | | | | | | | | | | | |
Collapse
|
42
|
Tsukada K, Nishio S, Usami S. A large cohort study ofGJB2mutations in Japanese hearing loss patients. Clin Genet 2010; 78:464-70. [DOI: 10.1111/j.1399-0004.2010.01407.x] [Citation(s) in RCA: 95] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
|
43
|
Connexin-26–associated deafness: Phenotypic variability and progression of hearing loss. Genet Med 2010; 12:174-81. [DOI: 10.1097/gim.0b013e3181d0d42b] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
|
44
|
Gap junctions in inherited human disease. Pflugers Arch 2010; 460:451-66. [PMID: 20140684 DOI: 10.1007/s00424-010-0789-1] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2009] [Revised: 01/05/2010] [Accepted: 01/12/2010] [Indexed: 12/16/2022]
Abstract
Gap junctions (GJ) provide direct intercellular communication. The structures underlying these cell junctions are membrane-associated channels composed of six integral membrane connexin (Cx) proteins, which can form communicating channels connecting the cytoplasms of adjacent cells. This provides coupled cells with a direct pathway for sharing ions, nutrients, or small metabolites to establish electrical coupling or balancing metabolites in various tissues. Genetic approaches have uncovered a still growing number of mutations in Cxs related to human diseases including deafness, skin disease, peripheral and central neuropathies, cataracts, or cardiovascular dysfunctions. The discovery of a growing number of inherited human disorders provides an unequivocal demonstration that gap junctional communication is crucial for diverse physiological processes.
Collapse
|
45
|
GREEN GLENNE, MUELLER ROBERTF, COHN EDWARDS, AVRAHAM KARENB, KANAAN MOIEN, SMITH RICHARDJH. Audiological Manifestations and Features of Connexin 26 Deafness. ACTA ACUST UNITED AC 2009. [DOI: 10.1080/16513860310003021] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
|
46
|
Carlsson P, Borg E, Grip L, Dahl N, Bondeson M. Variability in noise susceptibility in a Swedish population: the role of 35delG mutation in the connexin 26 (GJB2) gene. ACTA ACUST UNITED AC 2009. [DOI: 10.1080/16513860410035854] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
|
47
|
Cama E, Melchionda S, Palladino T, Carella M, Santarelli R, Genovese E, Benettazzo F, Zelante L, Arslan E. Hearing loss features in GJB2 biallelic mutations and GJB2/GJB6 digenic inheritance in a large Italian cohort. Int J Audiol 2009; 48:12-7. [DOI: 10.1080/14992020802400654] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
|
48
|
Kochhar A, Angeli SI, Dave SP, Liu XZ. Imaging correlation of children with DFNB1 vs non-DFNB1 hearing loss. Otolaryngol Head Neck Surg 2009; 140:665-9. [PMID: 19393408 DOI: 10.1016/j.otohns.2009.01.031] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2008] [Revised: 01/21/2009] [Accepted: 01/21/2009] [Indexed: 11/30/2022]
Abstract
OBJECTIVES To evaluate temporal bone CT findings in GJB2-related deafness (DFNB1) hearing loss and non-DFNB1 hearing loss children. STUDY DESIGN Case-control series. SUBJECTS AND METHODS Children with nonsyndromic hearing loss diagnosed as DFNB1 or non-DFNB1 after screening GJB2 allele variants and the large GJB6 deletion. Temporal bone CT images compared in a cohort of nine DFNB1 children with 10 non-DFNB1 children. Visual criteria and absolute measurements were compared against established normative values. RESULTS Visual inspection failed to identify two patients with abnormalities identified by using absolute measurements. Only one of nine DFNB1 children had an ear anomaly versus seven of 10 non-DFNB1 (odds ratio 16.33; 95% CI, 1.35, 197.78; P = 0.050). The non-DFNB1 group had a mean vestibule width that was significantly larger, and a mean lateral semicircular canal island width and vestibular aqueduct that were significantly smaller than the DFNB1 group. CONCLUSIONS Visual inspection of temporal bone CT images alone may not identify all anomalies and should be used with absolute CT measurements. Abnormal temporal bone CT findings are significantly less likely in children with DFNB1 compared with non-DFNB1 children despite similar age and degree of hearing loss.
Collapse
Affiliation(s)
- Amit Kochhar
- Department of Otolaryngology-Head and Neck Surgery, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | | | | | | |
Collapse
|
49
|
|
50
|
Kokotas H, Van Laer L, Grigoriadou M, Iliadou V, Economides J, Pomoni S, Pampanos A, Eleftheriades N, Ferekidou E, Korres S, Giannoulia-Karantana A, Van Camp G, Petersen MB. Strong linkage disequilibrium for the frequent GJB2 35delG mutation in the Greek population. Am J Med Genet A 2008; 146A:2879-84. [PMID: 18925674 DOI: 10.1002/ajmg.a.32546] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Approximately one in 1,000 children is affected by severe or profound hearing loss at birth or during early childhood (prelingual deafness). Up to 40% of congenital, autosomal recessive, severe to profound hearing impairment cases result from mutations in a single gene, GJB2, that encodes the connexin 26 protein. One specific mutation in this gene, 35delG, accounts for the majority of GJB2 mutations detected in Caucasian populations. Some previous studies have assumed that the high frequency of the 35delG mutation reflects the presence of a mutational hot spot, while other studies support the theory of a common founder. Greece is among the countries with the highest carrier frequency of the 35delG mutation (3.5%), and a recent study raised the hypothesis of the origin of this mutation in ancient Greece. We genotyped 60 Greek deafness patients homozygous for the 35delG mutation for six single nucleotide polymorphisms (SNPs) and two microsatellite markers inside or flanking the GJB2 gene. The allele distribution in the patients was compared to 60 Greek normal hearing controls. A strong linkage disequilibrium was found between the 35delG mutation and markers inside or flanking the GJB2 gene. Furthermore, we found a common haplotype with a previous study, suggesting a common founder for the 35delG mutation.
Collapse
Affiliation(s)
- Haris Kokotas
- Department of Genetics, Institute of Child Health, Athens, Greece
| | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|