1
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Ji H, Shu Y, Li H. Unveiling a novel GJB2 dominant K22T mutation in a Chinese family with hearing loss. Acta Biochim Biophys Sin (Shanghai) 2024; 56:945-951. [PMID: 38733163 PMCID: PMC11292126 DOI: 10.3724/abbs.2024064] [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: 11/17/2023] [Accepted: 01/16/2024] [Indexed: 05/13/2024] Open
Abstract
Hearing loss constitutes one of the most prevalent conditions within the field of otolaryngology. Recent investigations have revealed that mutations in deafness-associated genes, including point mutations and variations in DNA sequences, can cause hearing impairments. With the ethology of deafness remaining unclear for a substantial portion of the affected population, further screenings for pathogenic mutations are imperative to unveil the underlying mechanisms. On this study, by using next-generation sequencing, we examine 129 commonly implicated deafness-related genes in a Chinese family with hearing loss, revealing a novel heterozygous dominant mutation in the GJB2 gene (GJB2: c.65T>G: p. Lys22Thr). This mutation consistently occurs in affected family members but is not detected in unaffected individuals, strongly suggesting its causative role in hearing loss. Structural analysis indicates potential disruption to the Cx26 gap junction channel's hydrogen bond and electrostatic interactions, aligning with predictions from the PolyPhen and SIFT algorithms. In conclusion, our study provides conclusive evidence that the identified heterozygous GJB2 mutation (GJB2: c.65T>G: p. Lys22Thr), specifically the K22T alteration, is the primary determinant of the family's deafness. This contribution enhances our understanding of the interplay between common deafness-associated genes and hearing loss, offering valuable insights for diagnostic guidance and the formulation of therapeutic strategies for this condition.
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Affiliation(s)
- Haiting Ji
- Department of the Affiliated Eye and ENT HospitalState Key Laboratory of Medical NeurobiologyENT Institute and OtorhinolaryngologyFudan UniversityShanghai200031China
- NHC Key Laboratory of Hearing MedicineFudan UniversityShanghai200031China
- Shanghai Engineering Research Centre of Cochlear ImplantShanghai200031China
- ENT Institute and Otorhinolaryngology Department of Eye & ENT HospitalState Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain ScienceFudan UniversityShanghai200031China
| | - Yilai Shu
- Department of the Affiliated Eye and ENT HospitalState Key Laboratory of Medical NeurobiologyENT Institute and OtorhinolaryngologyFudan UniversityShanghai200031China
- NHC Key Laboratory of Hearing MedicineFudan UniversityShanghai200031China
- Shanghai Engineering Research Centre of Cochlear ImplantShanghai200031China
- ENT Institute and Otorhinolaryngology Department of Eye & ENT HospitalState Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain ScienceFudan UniversityShanghai200031China
- Institutes of Biomedical SciencesFudan UniversityShanghai200032China
| | - Huawei Li
- Department of the Affiliated Eye and ENT HospitalState Key Laboratory of Medical NeurobiologyENT Institute and OtorhinolaryngologyFudan UniversityShanghai200031China
- NHC Key Laboratory of Hearing MedicineFudan UniversityShanghai200031China
- Shanghai Engineering Research Centre of Cochlear ImplantShanghai200031China
- ENT Institute and Otorhinolaryngology Department of Eye & ENT HospitalState Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain ScienceFudan UniversityShanghai200031China
- Institutes of Biomedical SciencesFudan UniversityShanghai200032China
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2
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Mao L, Wang Y, An L, Zeng B, Wang Y, Frishman D, Liu M, Chen Y, Tang W, Xu H. Molecular Mechanisms and Clinical Phenotypes of GJB2 Missense Variants. BIOLOGY 2023; 12:biology12040505. [PMID: 37106706 PMCID: PMC10135792 DOI: 10.3390/biology12040505] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/18/2022] [Revised: 01/19/2023] [Accepted: 01/20/2023] [Indexed: 03/29/2023]
Abstract
The GJB2 gene is the most common gene responsible for hearing loss (HL) worldwide, and missense variants are the most abundant type. GJB2 pathogenic missense variants cause nonsyndromic HL (autosomal recessive and dominant) and syndromic HL combined with skin diseases. However, the mechanism by which these different missense variants cause the different phenotypes is unknown. Over 2/3 of the GJB2 missense variants have yet to be functionally studied and are currently classified as variants of uncertain significance (VUS). Based on these functionally determined missense variants, we reviewed the clinical phenotypes and investigated the molecular mechanisms that affected hemichannel and gap junction functions, including connexin biosynthesis, trafficking, oligomerization into connexons, permeability, and interactions between other coexpressed connexins. We predict that all possible GJB2 missense variants will be described in the future by deep mutational scanning technology and optimizing computational models. Therefore, the mechanisms by which different missense variants cause different phenotypes will be fully elucidated.
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Affiliation(s)
- Lu Mao
- Precision Medicine Center, Academy of Medical Science, Zhengzhou University, Zhengzhou 450052, China
| | - Yueqiang Wang
- Basecare Medical Device Co., Ltd., Suzhou 215000, China
| | - Lei An
- Translational Medicine Center, Huaihe Hospital of Henan University, Kaifeng 475000, China
| | - Beiping Zeng
- Precision Medicine Center, Academy of Medical Science, Zhengzhou University, Zhengzhou 450052, China
| | - Yanyan Wang
- The Research and Application Center of Precision Medicine, The Second Affiliated Hospital of Zhengzhou University, Zhengzhou 450014, China
| | - Dmitrij Frishman
- Wissenschaftszentrum Weihenstephan, Technische Universitaet Muenchen, Am Staudengarten 2, 85354 Freising, Germany
| | - Mengli Liu
- Precision Medicine Center, Academy of Medical Science, Zhengzhou University, Zhengzhou 450052, China
| | - Yanyu Chen
- Precision Medicine Center, Academy of Medical Science, Zhengzhou University, Zhengzhou 450052, China
| | - Wenxue Tang
- The Research and Application Center of Precision Medicine, The Second Affiliated Hospital of Zhengzhou University, Zhengzhou 450014, China
| | - Hongen Xu
- Precision Medicine Center, Academy of Medical Science, Zhengzhou University, Zhengzhou 450052, China
- The Research and Application Center of Precision Medicine, The Second Affiliated Hospital of Zhengzhou University, Zhengzhou 450014, China
- Correspondence:
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3
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Li MM, Tayoun AA, DiStefano M, Pandya A, Rehm HL, Robin NH, Schaefer AM, Yoshinaga-Itano C. Clinical evaluation and etiologic diagnosis of hearing loss: A clinical practice resource of the American College of Medical Genetics and Genomics (ACMG). Genet Med 2022; 24:1392-1406. [PMID: 35802133 DOI: 10.1016/j.gim.2022.03.018] [Citation(s) in RCA: 18] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2022] [Accepted: 03/28/2022] [Indexed: 11/26/2022] Open
Abstract
Hearing loss is a common and complex condition that can occur at any age, can be inherited or acquired, and is associated with a remarkably wide array of etiologies. The diverse causes of hearing loss, combined with the highly variable and often overlapping presentations of different forms of hearing loss, challenge the ability of traditional clinical evaluations to arrive at an etiologic diagnosis for many deaf and hard-of-hearing individuals. However, identifying the etiology of hearing loss may affect clinical management, improve prognostic accuracy, and refine genetic counseling and assessment of the likelihood of recurrence for relatives of deaf and hard-of-hearing individuals. Linguistic and cultural identities associated with being deaf or hard-of-hearing can complicate access to and the effectiveness of clinical care. These concerns can be minimized when genetic and other health care services are provided in a linguistically and culturally sensitive manner. This clinical practice resource offers information about the frequency, causes, and presentations of hearing loss and suggests approaches to the clinical and genetic evaluation of deaf and hard-of-hearing individuals aimed at identifying an etiologic diagnosis and providing informative and effective patient education and genetic counseling.
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Affiliation(s)
- Marilyn M Li
- Department of Pathology and Laboratory Medicine, Department of Pediatrics, Children's Hospital of Philadelphia, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA
| | - Ahmad Abou Tayoun
- Al Jalila Genomics Center, Al Jalila Children's Specialty Hospital, Mohammed Bin Rashid University, Dubai, United Arab Emirates
| | | | - Arti Pandya
- Department of Pediatrics, University of North Carolina School of Medicine, Chapel Hill, NC
| | - Heidi L Rehm
- Program in Medical and Population Genetics, Broad Institute of MIT and Harvard, Cambridge, MA
| | - Nathaniel H Robin
- Departments of Genetics and Pediatrics, University of Alabama at Birmingham, Birmingham, AL
| | - Amanda M Schaefer
- Department of Otolaryngology-Head & Neck Surgery, Molecular Otolaryngology and Renal Research Laboratories, University of Iowa, Iowa City, IA
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4
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Lukowicz-Bedford RM, Farnsworth DR, Miller AC. Connexinplexity: the spatial and temporal expression of connexin genes during vertebrate organogenesis. G3 (BETHESDA, MD.) 2022; 12:jkac062. [PMID: 35325106 PMCID: PMC9073686 DOI: 10.1093/g3journal/jkac062] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/19/2021] [Accepted: 02/24/2022] [Indexed: 11/28/2022]
Abstract
Animal development requires coordinated communication between cells. The Connexin family of proteins is a major contributor to intercellular communication in vertebrates by forming gap junction channels that facilitate the movement of ions, small molecules, and metabolites between cells. Additionally, individual hemichannels can provide a conduit to the extracellular space for paracrine and autocrine signaling. Connexin-mediated communication is widely used in epithelial, neural, and vascular development and homeostasis, and most tissues likely use this form of communication. In fact, Connexin disruptions are of major clinical significance contributing to disorders developing from all major germ layers. Despite the fact that Connexins serve as an essential mode of cellular communication, the temporal and cell-type-specific expression patterns of connexin genes remain unknown in vertebrates. A major challenge is the large and complex connexin gene family. To overcome this barrier, we determined the expression of all connexins in zebrafish using single-cell RNA-sequencing of entire animals across several stages of organogenesis. Our analysis of expression patterns has revealed that few connexins are broadly expressed, but rather, most are expressed in tissue- or cell-type-specific patterns. Additionally, most tissues possess a unique combinatorial signature of connexin expression with dynamic temporal changes across the organism, tissue, and cell. Our analysis has identified new patterns for well-known connexins and assigned spatial and temporal expression to genes with no-existing information. We provide a field guide relating zebrafish and human connexin genes as a critical step toward understanding how Connexins contribute to cellular communication and development throughout vertebrate organogenesis.
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Affiliation(s)
| | - Dylan R Farnsworth
- Institute of Neuroscience, Department of Biology, University of Oregon, Eugene, OR 97403, USA
| | - Adam C Miller
- Institute of Neuroscience, Department of Biology, University of Oregon, Eugene, OR 97403, USA
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5
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Garcia-Vega L, O’Shaughnessy EM, Albuloushi A, Martin PE. Connexins and the Epithelial Tissue Barrier: A Focus on Connexin 26. BIOLOGY 2021; 10:biology10010059. [PMID: 33466954 PMCID: PMC7829877 DOI: 10.3390/biology10010059] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/21/2020] [Revised: 01/11/2021] [Accepted: 01/12/2021] [Indexed: 12/15/2022]
Abstract
Simple Summary Tissues that face the external environment are known as ‘epithelial tissue’ and form barriers between different body compartments. This includes the outer layer of the skin, linings of the intestine and airways that project into the lumen connecting with the external environment, and the cornea of the eye. These tissues do not have a direct blood supply and are dependent on exchange of regulatory molecules between cells to ensure co-ordination of tissue events. Proteins known as connexins form channels linking cells directly and permit exchange of small regulatory signals. A range of environmental stimuli can dysregulate the level of connexin proteins and or protein function within the epithelia, leading to pathologies including non-healing wounds. Mutations in these proteins are linked with hearing loss, skin and eye disorders of differing severity. As such, connexins emerge as prime therapeutic targets with several agents currently in clinical trials. This review outlines the role of connexins in epithelial tissue and how their dysregulation contributes to pathological pathways. Abstract Epithelial tissue responds rapidly to environmental triggers and is constantly renewed. This tissue is also highly accessible for therapeutic targeting. This review highlights the role of connexin mediated communication in avascular epithelial tissue. These proteins form communication conduits with the extracellular space (hemichannels) and between neighboring cells (gap junctions). Regulated exchange of small metabolites less than 1kDa aide the co-ordination of cellular activities and in spatial communication compartments segregating tissue networks. Dysregulation of connexin expression and function has profound impact on physiological processes in epithelial tissue including wound healing. Connexin 26, one of the smallest connexins, is expressed in diverse epithelial tissue and mutations in this protein are associated with hearing loss, skin and eye conditions of differing severity. The functional consequences of dysregulated connexin activity is discussed and the development of connexin targeted therapeutic strategies highlighted.
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6
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Alghamdi MA, AL-Eitan LN, Tarkhan AH, Al-Qarqaz FA. Global gene methylation profiling of common warts caused by human papillomaviruses infection. Saudi J Biol Sci 2021; 28:612-622. [PMID: 33424347 PMCID: PMC7783806 DOI: 10.1016/j.sjbs.2020.10.050] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2020] [Revised: 10/20/2020] [Accepted: 10/21/2020] [Indexed: 12/23/2022] Open
Abstract
Infection with the human papillomaviruses (HPV) often involves the epigenetic modification of the host genome. Despite its prevalence among the population, host genome methylation in HPV-induced warts is not clearly understood. In this study, genome-wide methylation profiling was carried out on paired healthy skin and wart samples in order to investigate the effects that benign HPV infection has on gene methylation status. To overcome this gap in knowledge, paired wart (n = 12) and normal skin (n = 12) samples were obtained from Arab males in order to perform DNA extraction and subsequent genome-wide methylation profiling on the Infinium Methylation EPIC Bead Chip microarray. Analysis of differential methylation revealed a clear pattern of discrimination between the wart and normal skin samples. In warts, the most differentially methylated (DM) genes included long non-coding RNAs (AC005884, AL049646.2, AC126121.2, AP001790.1, and AC107959.3), microRNAs (MIR374B, MIR596, MIR1255B1, MIR26B, and MIR196A2),snoRNAs (SNORD114-22, SNORD70, and SNORD114-31), pseudogenes (AC069366.1, RNU4ATAC11P, AC120057.1, NANOGP3, AC106038.2, TPT1P2, SDC4P, PKMP3, and VN2R3P), and protein-coding genes (AREG, GJB2, C12orf71, AC020909.2, S100A8, ZBED2, FABP7, and CYSLTR1). In addition, pathway analysis revealed that, among the most differentially methylated genes, STAT5A, RARA, MEF2D, MAP3K8, and THRA were the common regulators. It can be observed that HPV-induced warts involve a clear and unique epigenetic alteration to the host genome.
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Affiliation(s)
- Mansour A. Alghamdi
- Department of Anatomy, College of Medicine, King Khalid University, Abha 61421, Saudi Arabia
- Genomics and Personalized Medicine Unit, College of Medicine, King Khalid University, Abha 61421, Saudi Arabia
| | - Laith N. AL-Eitan
- Department of Applied Biological Sciences, Jordan University of Science and Technology, Irbid 22110, Jordan
- Department of Biotechnology and Genetic Engineering, Jordan University of Science and Technology, Irbid 22110, Jordan
| | - Amneh H. Tarkhan
- Department of Applied Biological Sciences, Jordan University of Science and Technology, Irbid 22110, Jordan
| | - Firas A. Al-Qarqaz
- Department of Internal Medicine, Jordan University of Science and Technology, Irbid 22110, Jordan
- Division of Dermatology, Department of Internal Medicine, King Abdullah University Hospital Jordan University of Science and Technology, Irbid 22110, Jordan
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7
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Lee TL, Lin PH, Chen PL, Hong JB, Wu CC. Hereditary Hearing Impairment with Cutaneous Abnormalities. Genes (Basel) 2020; 12:43. [PMID: 33396879 PMCID: PMC7823799 DOI: 10.3390/genes12010043] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2020] [Revised: 12/25/2020] [Accepted: 12/26/2020] [Indexed: 12/15/2022] Open
Abstract
Syndromic hereditary hearing impairment (HHI) is a clinically and etiologically diverse condition that has a profound influence on affected individuals and their families. As cutaneous findings are more apparent than hearing-related symptoms to clinicians and, more importantly, to caregivers of affected infants and young individuals, establishing a correlation map of skin manifestations and their underlying genetic causes is key to early identification and diagnosis of syndromic HHI. In this article, we performed a comprehensive PubMed database search on syndromic HHI with cutaneous abnormalities, and reviewed a total of 260 relevant publications. Our in-depth analyses revealed that the cutaneous manifestations associated with HHI could be classified into three categories: pigment, hyperkeratosis/nail, and connective tissue disorders, with each category involving distinct molecular pathogenesis mechanisms. This outline could help clinicians and researchers build a clear atlas regarding the phenotypic features and pathogenetic mechanisms of syndromic HHI with cutaneous abnormalities, and facilitate clinical and molecular diagnoses of these conditions.
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Affiliation(s)
- Tung-Lin Lee
- Department of Medical Education, National Taiwan University Hospital, Taipei City 100, Taiwan;
| | - Pei-Hsuan Lin
- Department of Otolaryngology, National Taiwan University Hospital, Taipei 11556, Taiwan;
- Graduate Institute of Clinical Medicine, National Taiwan University College of Medicine, Taipei City 100, Taiwan;
| | - Pei-Lung Chen
- Graduate Institute of Clinical Medicine, National Taiwan University College of Medicine, Taipei City 100, Taiwan;
- Graduate Institute of Medical Genomics and Proteomics, National Taiwan University College of Medicine, Taipei City 100, Taiwan
- Department of Medical Genetics, National Taiwan University Hospital, Taipei 10041, Taiwan
- Department of Internal Medicine, National Taiwan University Hospital, Taipei 10041, Taiwan
| | - Jin-Bon Hong
- Graduate Institute of Medical Genomics and Proteomics, National Taiwan University College of Medicine, Taipei City 100, Taiwan
- Department of Dermatology, National Taiwan University Hospital, Taipei City 100, Taiwan
| | - Chen-Chi Wu
- Department of Otolaryngology, National Taiwan University Hospital, Taipei 11556, Taiwan;
- Graduate Institute of Clinical Medicine, National Taiwan University College of Medicine, Taipei City 100, Taiwan;
- Department of Medical Genetics, National Taiwan University Hospital, Taipei 10041, Taiwan
- Department of Medical Research, National Taiwan University Biomedical Park Hospital, Hsinchu City 300, Taiwan
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8
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Affiliation(s)
- Vivek Kumar Dey
- Department of Dermatology, People's College of Medial Sciences and Research Centre, Bhopal, Madhya Pradesh, India
| | - Animesh Saxena
- Department of Dermatology, People's College of Medial Sciences and Research Centre, Bhopal, Madhya Pradesh, India
| | - Shrini Parikh
- Department of Dermatology, People's College of Medial Sciences and Research Centre, Bhopal, Madhya Pradesh, India
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9
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A case of keratitis, ichthyosis, and deafness syndrome with rickets. JAAD Case Rep 2020; 6:9-12. [PMID: 31890828 PMCID: PMC6928269 DOI: 10.1016/j.jdcr.2019.10.024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
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10
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Bussini A, Righi R, Pessina C, Genoni A, Cristofari E, Meli A, Granata P, Meroni E, Broccolo F, Casalone R. The p.Gly130Val mutation in the GJB2 gene: A familiar case of autosomal dominant non-syndromic hearing loss. Int J Pediatr Otorhinolaryngol 2019; 127:109653. [PMID: 31472357 DOI: 10.1016/j.ijporl.2019.109653] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/09/2019] [Revised: 08/01/2019] [Accepted: 08/20/2019] [Indexed: 11/27/2022]
Abstract
Several forms of sensorineural hearing loss (SNHL) have been imputated to connexins mutations and prevalently to connexin 26 (Cx26), codified by the GJB2 gene (gap junction protein, beta 2). Here, we report the first familiar case (heterozygous p. G130V mutation) of non-syndromic (without any dermatological manifestation) dominant profound SNHL. Proband was a 6-years-old male with post-lingual bilateral profound SNHL, clinically identified at the age of 3 with diagnosis of severe SNHL. We confirm that the p. G130V variant of the GJB2 gene is causative of autosomal dominant form of SNHL, although it is not always associated with the presence of skin diseases.
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Affiliation(s)
- Adelaide Bussini
- Unit of Cytogenetics and Medical Genetic, ASST Settelaghi, Varese, Italy
| | - Rossana Righi
- Unit of Cytogenetics and Medical Genetic, ASST Settelaghi, Varese, Italy
| | - Chiara Pessina
- Unit of Cytogenetics and Medical Genetic, ASST Settelaghi, Varese, Italy
| | - Angelo Genoni
- Unit of Cytogenetics and Medical Genetic, ASST Settelaghi, Varese, Italy
| | | | | | - Paola Granata
- Unit of Cytogenetics and Medical Genetic, ASST Settelaghi, Varese, Italy
| | - Emanuela Meroni
- Unit of Cytogenetics and Medical Genetic, ASST Settelaghi, Varese, Italy
| | - Francesco Broccolo
- Department of Medicine and Surgery (School of Medicine), University of Milano-Bicocca, Monza, Italy.
| | - Rosario Casalone
- Unit of Cytogenetics and Medical Genetic, ASST Settelaghi, Varese, Italy.
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11
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G130V de novo mutation in an Iranian pedigree with nonsyndromic hearing loss without palmoplantar keratoderma. Int J Pediatr Otorhinolaryngol 2019; 126:109607. [PMID: 31419744 DOI: 10.1016/j.ijporl.2019.109607] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/13/2019] [Revised: 07/12/2019] [Accepted: 07/21/2019] [Indexed: 11/22/2022]
Abstract
Mutations in the GJB2 gene encoding connexin 26 (Cx26) cause autosomal recessive and rarely dominant nonsyndromic sensorineural hearing loss as well as asyndromic hearing impairment with skin problems. A dominant GJB2 mutation, c.389G > T (p.G130V), has been reported previously in association with hearing impairment and palmoplantar keratoderm. Here we report the first de novo G130V mutation of GJB2 gene in a sporadic case of hearing loss in a consanguineous Iranian family which is not associated with skin disorder.
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12
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Hamadah I, Haider M, Chisti M. A novel homozygous mutation of GJB2-A new variant of keratitis-ichthyosis-deafness syndrome? JAAD Case Rep 2019; 5:283-287. [PMID: 30891482 PMCID: PMC6403109 DOI: 10.1016/j.jdcr.2019.01.014] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Affiliation(s)
- Issam Hamadah
- Dermatology Department, King Faisal Specialist Hospital and Research Center, Riyadh, Saudi Arabia
| | - Mansoor Haider
- Dermatology Department, King Faisal Specialist Hospital and Research Center, Riyadh, Saudi Arabia
| | - Muzamil Chisti
- Dermatology Department, King Faisal Specialist Hospital and Research Center, Riyadh, Saudi Arabia
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13
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Evidence for an autosomal recessive pattern of inheritance in Keratitis-ichthyosis-deafness (KID) syndrome: Exome sequencing reveals a novel homozygous GJB2 mutation. Meta Gene 2019. [DOI: 10.1016/j.mgene.2018.10.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
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14
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Albano JMR, Mussini N, Toriano R, Facelli JC, Ferraro MB, Pickholz M. Calcium interactions with Cx26 hemmichannel: Spatial association between MD simulations biding sites and variant pathogenicity. Comput Biol Chem 2018; 77:331-342. [PMID: 30466042 DOI: 10.1016/j.compbiolchem.2018.11.004] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2018] [Revised: 07/08/2018] [Accepted: 11/08/2018] [Indexed: 01/23/2023]
Abstract
Connexinophaties are a collective of diseases related to connexin channels and hemichannels. In particular many Cx26 alterations are strongly associated to human deafness. Calcium plays an important role on this structures regulation. Here, using calcium as a probe, extensive atomistic Molecular Dynamics simulations were performed on the Cx26 hemichannel embedded in a lipid bilayer. Exploring different initial conditions and calcium concentration, simulation reached ∼4 μs. Several analysis were carried out in order to reveal the calcium distribution and localization, such as electron density profiles, density maps and distance time evolution, which is directly associated to the interaction energy. Specific amino acid interactions with calcium and their stability were capture within this context. Few of these sites such as, GLU42, GLU47, GLY45 and ASP50, were already suggested in the literature. Besides, we identified novel calcium biding sites: ASP2, ASP117, ASP159, GLU114, GLU119, GLU120 and VAL226. To the best of our knowledge, this is the first time that these sites are reported within this context. Furthermore, since various pathologies involving the Cx26 hemichannel are associated with pathogenic variants in the corresponding CJB2 gene, using ClinVar, we were able to spatially associate the 3D positions of the identified calcium binding sites within the framework of this work with reported pathogenic variants in the CJB2 gene. This study presents a first step on finding associations between molecular features and pathological variants of the Cx26 hemichannel.
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Affiliation(s)
- Juan M R Albano
- Facultad de Ciencias Exactas y Naturales, Departamento de Física, Universidad de Buenos Aires, Argentina; CONICET- Universidad de Buenos Aires, IFIBA, Buenos Aires, Argentina
| | - Nahuel Mussini
- Facultad de Ciencias Exactas y Naturales, Departamento de Física, Universidad de Buenos Aires, Argentina; CONICET- Universidad de Buenos Aires, IFIBA, Buenos Aires, Argentina
| | - Roxana Toriano
- Facultad de Medicina, Departamento de Ciencias Fisiológicas, Laboratorio de Biomembranas, Buenos Aires, Argentina; CONICET - Universidad de Buenos Aires, IFIBIO Houssay, Buenos Aires, Argentina
| | - Julio C Facelli
- Department of Biomedical Informatics, The University of Utah, 421 Wakara Way, Suite 140, Salt Lake City, UT 84108, USA.
| | - Marta B Ferraro
- Facultad de Ciencias Exactas y Naturales, Departamento de Física, Universidad de Buenos Aires, Argentina; CONICET- Universidad de Buenos Aires, IFIBA, Buenos Aires, Argentina
| | - Mónica Pickholz
- Facultad de Ciencias Exactas y Naturales, Departamento de Física, Universidad de Buenos Aires, Argentina; CONICET- Universidad de Buenos Aires, IFIBA, Buenos Aires, Argentina
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15
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DeMille D, Carlston CM, Tam OH, Palumbos JC, Stalker HJ, Mao R, Zori RT, Viskochil DH, Park AH, Carey JC. Three novel
GJB2
(connexin 26) variants associated with autosomal dominant syndromic and nonsyndromic hearing loss. Am J Med Genet A 2018; 176:945-950. [DOI: 10.1002/ajmg.a.38648] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2017] [Revised: 01/27/2018] [Accepted: 01/29/2018] [Indexed: 11/09/2022]
Affiliation(s)
- Desiree DeMille
- ARUP Institute for Clinical and Experimental PathologySalt Lake City Utah
| | - Colleen M. Carlston
- ARUP Institute for Clinical and Experimental PathologySalt Lake City Utah
- Department of PathologyUniversity of UtahSalt Lake City Utah
| | - Oliver H. Tam
- ARUP Institute for Clinical and Experimental PathologySalt Lake City Utah
| | - Janice C. Palumbos
- Department of Pediatrics, Division of Medical GeneticsUniversity of UtahSalt Lake City Utah
| | - Heather J. Stalker
- Division of Pediatric Genetics and MetabolismUniversity of FloridaGainesville Florida
| | - Rong Mao
- ARUP Institute for Clinical and Experimental PathologySalt Lake City Utah
- Department of PathologyUniversity of UtahSalt Lake City Utah
| | - Roberto T. Zori
- Division of Pediatric Genetics and MetabolismUniversity of FloridaGainesville Florida
| | - David H. Viskochil
- Department of Pediatrics, Division of Medical GeneticsUniversity of UtahSalt Lake City Utah
| | - Albert H. Park
- Division of Otolaryngology – Head and Neck SurgeryUniversity of UtahSalt Lake City Utah
| | - John C. Carey
- Department of Pediatrics, Division of Medical GeneticsUniversity of UtahSalt Lake City Utah
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16
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Arai Y, Takahashi M, Sakuma N, Nisio SY, Oridate N, Usami SI. Compound heterozygous dominant and recessive GJB2 mutations cause deafness with palmoplantar keratoderma. ACTA OTO-LARYNGOLOGICA CASE REPORTS 2017. [DOI: 10.1080/23772484.2017.1376587] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022] Open
Affiliation(s)
- Yasuhiro Arai
- Department of Otorhinolaryngology, Head and Neck Surgery, School of Medicine, Yokohama City University, Yokohama, Japan
| | - Masahiro Takahashi
- Department of Otorhinolaryngology, Head and Neck Surgery, School of Medicine, Yokohama City University, Yokohama, Japan
| | - Naoko Sakuma
- Department of Otorhinolaryngology, Head and Neck Surgery, School of Medicine, Yokohama City University, Yokohama, Japan
| | - Shin-Ya Nisio
- Department of Otorhinolaryngology, Shinshu University School of Medicine, Matsumoto, Japan
| | - Nobuhiko Oridate
- Department of Otorhinolaryngology, Head and Neck Surgery, School of Medicine, Yokohama City University, Yokohama, Japan
| | - Shin-Ichi Usami
- Department of Otorhinolaryngology, Shinshu University School of Medicine, Matsumoto, Japan
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17
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Wong P, Laxton V, Srivastava S, Chan YWF, Tse G. The role of gap junctions in inflammatory and neoplastic disorders (Review). Int J Mol Med 2017; 39:498-506. [PMID: 28098880 PMCID: PMC5360388 DOI: 10.3892/ijmm.2017.2859] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2016] [Accepted: 12/23/2016] [Indexed: 12/29/2022] Open
Abstract
Gap junctions are intercellular channels made of connexin proteins, mediating both electrical and biochemical signals between cells. The ability of gap junction proteins to regulate immune responses, cell proliferation, migration, apoptosis and carcinogenesis makes them attractive therapeutic targets for treating inflammatory and neoplastic disorders in different organ systems. Alterations in gap junction profile and expression levels are observed in hyperproliferative skin disorders, lymphatic vessel diseases, inflammatory lung diseases, liver injury and neoplastic disorders. It is now recognized that the therapeutic effects mediated by traditional pharmacological agents are dependent upon gap junction communication and may even act by influencing gap junction expression or function. Novel strategies for modulating the function or expression of connexins, such as the use of synthetic mimetic peptides and siRNA technology are considered.
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Affiliation(s)
- Pui Wong
- School of Biomedical Sciences, Li Ka Shing Faculty of Medicine, University of Hong Kong, Hong Kong, SAR, P.R. China
| | - Victoria Laxton
- Intensive Care Department, Royal Brompton and Harefield NHS Foundation Trust, London SW3 6NP
| | | | - Yin Wah Fiona Chan
- School of Biological Sciences, University of Cambridge, Cambridge CB2 1AG, UK
| | - Gary Tse
- Department of Medicine and Therapeutics
- Li Ka Shing Institute of Health Sciences, Faculty of Medicine, Chinese University of Hong Kong, Hong Kong, SAR, P.R. China
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18
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García IE, Prado P, Pupo A, Jara O, Rojas-Gómez D, Mujica P, Flores-Muñoz C, González-Casanova J, Soto-Riveros C, Pinto BI, Retamal MA, González C, Martínez AD. Connexinopathies: a structural and functional glimpse. BMC Cell Biol 2016; 17 Suppl 1:17. [PMID: 27228968 PMCID: PMC4896260 DOI: 10.1186/s12860-016-0092-x] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
Mutations in human connexin (Cx) genes have been related to diseases, which we termed connexinopathies. Such hereditary disorders include nonsyndromic or syndromic deafness (Cx26, Cx30), Charcot Marie Tooth disease (Cx32), occulodentodigital dysplasia and cardiopathies (Cx43), and cataracts (Cx46, Cx50). Despite the clinical phenotypes of connexinopathies have been well documented, their pathogenic molecular determinants remain elusive. The purpose of this work is to identify common/uncommon patterns in channels function among Cx mutations linked to human diseases. To this end, we compiled and discussed the effect of mutations associated to Cx26, Cx32, Cx43, and Cx50 over gap junction channels and hemichannels, highlighting the function of the structural channel domains in which mutations are located and their possible role affecting oligomerization, gating and perm/selectivity processes.
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Affiliation(s)
- Isaac E García
- Centro Interdisciplinario de Neurociencia de Valparaíso, Instituto de Neurociencia, Facultad de Ciencias, Universidad de Valparaíso, Valparaíso, Chile
| | - Pavel Prado
- Centro Interdisciplinario de Neurociencia de Valparaíso, Instituto de Neurociencia, Facultad de Ciencias, Universidad de Valparaíso, Valparaíso, Chile
| | - Amaury Pupo
- Centro Interdisciplinario de Neurociencia de Valparaíso, Instituto de Neurociencia, Facultad de Ciencias, Universidad de Valparaíso, Valparaíso, Chile
| | - Oscar Jara
- Centro Interdisciplinario de Neurociencia de Valparaíso, Instituto de Neurociencia, Facultad de Ciencias, Universidad de Valparaíso, Valparaíso, Chile
| | - Diana Rojas-Gómez
- Centro Interdisciplinario de Neurociencia de Valparaíso, Instituto de Neurociencia, Facultad de Ciencias, Universidad de Valparaíso, Valparaíso, Chile
| | - Paula Mujica
- Centro Interdisciplinario de Neurociencia de Valparaíso, Instituto de Neurociencia, Facultad de Ciencias, Universidad de Valparaíso, Valparaíso, Chile
| | - Carolina Flores-Muñoz
- Centro Interdisciplinario de Neurociencia de Valparaíso, Instituto de Neurociencia, Facultad de Ciencias, Universidad de Valparaíso, Valparaíso, Chile
| | - Jorge González-Casanova
- Centro Interdisciplinario de Neurociencia de Valparaíso, Instituto de Neurociencia, Facultad de Ciencias, Universidad de Valparaíso, Valparaíso, Chile
| | - Carolina Soto-Riveros
- Centro Interdisciplinario de Neurociencia de Valparaíso, Instituto de Neurociencia, Facultad de Ciencias, Universidad de Valparaíso, Valparaíso, Chile
| | - Bernardo I Pinto
- Centro Interdisciplinario de Neurociencia de Valparaíso, Instituto de Neurociencia, Facultad de Ciencias, Universidad de Valparaíso, Valparaíso, Chile
| | - Mauricio A Retamal
- Centro de Fisiología Celular e Integrativa, Facultad de Medicina, Clínica Alemana Universidad del Desarrollo, Santiago, Chile
| | - Carlos González
- Centro Interdisciplinario de Neurociencia de Valparaíso, Instituto de Neurociencia, Facultad de Ciencias, Universidad de Valparaíso, Valparaíso, Chile
| | - Agustín D Martínez
- Centro Interdisciplinario de Neurociencia de Valparaíso, Instituto de Neurociencia, Facultad de Ciencias, Universidad de Valparaíso, Valparaíso, Chile.
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19
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Genetic Testing for Deaf and Hard of Hearing Individuals: Genetic Counseling. CURRENT GENETIC MEDICINE REPORTS 2016. [DOI: 10.1007/s40142-016-0089-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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20
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Intra-familial phenotypic variability in a Moroccan family with hearing loss and palmoplantar keratoderma (PPK). Curr Res Transl Med 2016; 64:61-4. [PMID: 27316387 DOI: 10.1016/j.retram.2016.01.011] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2015] [Accepted: 01/27/2016] [Indexed: 01/03/2023]
Abstract
Mutations in the GJB2 gene encoding connexin 26 are the main cause of hereditary hearing impairment. These mutations generate mainly autosomal recessive and rarely autosomal dominant deafness. Dominant mutations in GJB2 can be responsible for isolated deafness as well as syndromic hearing loss associated with various skin abnormalities. Until now few papers discuss dominant mutations in the GJB2 gene. In this work we report a rare case about a Moroccan family with a compound heterozygous mutation (the dominant p.R75Q and the recessive c.35delG alleles) in the GJB2 gene with intra-familial phenotypic variability. This study reinforces the involvement of p.R75Q mutation of GJB2 in syndromic deafness associated with dermatological diseases the palmoplantar keratoderma.
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21
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Markova TG, Brazhkina NB, Bliznech EA, Bakhshinyan VV, Polyakov AV, Tavartkiladze GA. Phenotype in a patient with p.D50N mutation in GJB2 gene resemble both KID and Clouston syndromes. Int J Pediatr Otorhinolaryngol 2016; 81:10-4. [PMID: 26810281 DOI: 10.1016/j.ijporl.2015.11.022] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/22/2015] [Revised: 11/13/2015] [Accepted: 11/18/2015] [Indexed: 11/18/2022]
Abstract
Keratitis-ichthyosis-deafness (KID) syndrome (OMIM 148210) is a rare ectodermal dysplasia syndrome characterized by vascularizing keratitis, congenital profound sensorineural hearing loss, and progressive erythrokeratoderma. We have found a 148G-A transition in the GJB2 gene, resulting in an asp50-to-asn (D50N) substitution in a girl with congenital deafness. This finding allowed us to diagnose а KID syndrome. But clinical features were uncommon because of a mild skin manifestation, lack of keratitis and unusual appearance resembling Clouston syndrome. Molecular genetic tests showed that it was de novo mutation because parents have normal genotype. Several autosomal dominant mutations in the GJB2 gene (сonnexin 26) now established to underlie many of the affected cases, with the majority of patients harboring the p.D50N mutation. Skin disease-associated mutation of connexin proteins can cause functional disturbances in gap junction intercellular conductance. It is likely that multiple disease mechanisms are involved across the wide spectrum of hereditary diseases relating to connexin proteins. The clinical data may provide additional insights into the dysregulation mechanisms of mutations result in the disease.
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Affiliation(s)
- T G Markova
- Department the Epidemiology and Genetics of Hearing Loss, National Research Center for Audiology and Hearing Rehabilitation, 123 Leninsky Ave, 117513 Moscow, Russia.
| | - N B Brazhkina
- Out-Patient Clinic, National Research Center for Audiology and Hearing Rehabilitation, 123 Leninsky Ave, 117513 Moscow, Russia
| | - E A Bliznech
- Laboratory for DNA-Diagnostics, Federal State Budgetary Institution "Research Centre for Medical Genetics", 1, Room 116 Moskvorechie Str, 115478 Moscow, Russia.
| | - V V Bakhshinyan
- Cochlear Implants Center, National Research Center for Audiology and Hearing Rehabilitation, 123 Leninsky Ave, 117513 Moscow, Russia.
| | - A V Polyakov
- Laboratory for DNA-Diagnostics, Federal State Budgetary Institution "Research Centre for Medical Genetics", 1, Room 116 Moskvorechie Str, 115478 Moscow, Russia.
| | - G A Tavartkiladze
- National Research Center for Audiology and Hearing Rehabilitation, 123 Leninsky Ave, 117513 Moscow, Russia.
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22
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Mercer D. Guidelines for Audiologists on the Benefits and Limitations of Genetic Testing. Am J Audiol 2015; 24:451-61. [PMID: 25996947 DOI: 10.1044/2015_aja-15-0010] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2015] [Accepted: 05/17/2015] [Indexed: 12/16/2022] Open
Abstract
PURPOSE This tutorial provides information to aid audiologists in determining when a referral for a genetics evaluation is appropriate for a patient with hearing loss. Direction is given on discussing the benefits and limitations of genetic testing with parents of children with hearing loss. METHOD Genetic patterns of inheritance are reviewed, particularly in reference to syndromic and nonsyndromic forms of hearing loss. A review of pertinent literature was performed. CONCLUSION Audiologists are in a unique position to facilitate investigation into the etiology of a patient's hearing loss. This is of high importance in genetic etiologies because the diagnosis can provide information on recurrence risks and other potential health implications. Suggestions are made to help audiologists recognize when a genetics referral is warranted, counsel patients and their parents about the benefits and limitations of genetic testing, and interpret genetic test results.
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Affiliation(s)
- Danielle Mercer
- The Louisiana State University Health Sciences Center, New Orleans, LA
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23
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Abstract
Connexin mutations underlie numerous human genetic diseases. Several connexin genes have been linked to skin diseases, and mechanistic studies have indicated that a gain of abnormal channel function may be responsible for pathology. The topical accessibility of the epidermal connexins, the existence of several mouse models of human skin disease, and the ongoing identification of pharmacological inhibitors targeting connexins provide an opportunity to test new therapeutic approaches.
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Affiliation(s)
- Noah A Levit
- Department of Physiology and Biophysics, Stony Brook University, Stony Brook, NY 11794, United States
| | - Thomas W White
- Department of Physiology and Biophysics, Stony Brook University, Stony Brook, NY 11794, United States.
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24
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Kashef A, Nikzat N, Bazzazadegan N, Fattahi Z, Sabbagh-Kermani F, Taghdiri M, Azadeh B, Mojahedi F, Khoshaeen A, Habibi H, Najmabadi H, Kahrizi K. Finding mutation within non-coding region of GJB2 reveals its importance in genetic testing of hearing loss in Iranian population. Int J Pediatr Otorhinolaryngol 2015; 79:136-8. [PMID: 25555641 DOI: 10.1016/j.ijporl.2014.11.024] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/18/2014] [Revised: 11/17/2014] [Accepted: 11/21/2014] [Indexed: 11/17/2022]
Abstract
OBJECTIVE Hereditary hearing loss is the most common neurosensory disorder in humans. Half of the cases have genetic etiology with extraordinary genetic heterogeneity. Mutations in one gene, GJB2, are the most common cause for autosomal recessive non-syndromic hearing loss (ARNSHL) in many different populations. GJB2 encodes a gap junction channel protein (connexin 26), and is located on DFNB1 locus on chromosome 13q12.11 which also involve another connexin gene, GJB6. Mutation screening of GJB2 revealed that a high number of patients with deaf phenotype have heterozygous genotype and carry only one mutant allele. As the first comprehensive study in Iran, we have targeted GJB2-related Iranian heterozygotes, looking for second mutant allele which leads to hearing impairment. They bear first mutation in their coding exon of GJB2. METHOD Using PCR-based direct sequencing, we assessed 103 patients with ARNSHL for variants in non-coding exon and promoter region of this gene, for the first time in Iran. RESULT We have identified the second mutant allele in splice site of exon-1 of GJB2 which is known as IVS1+1G>A in 17 probands. We found no mutation in promoter region of GJB2. CONCLUSION Our findings reveal that IVS1+1G>A mutation in noncoding exon of GJB2 is the most common mutation after 35delG within multi ethnical Iranian heterozygote samples. It emphasizes to approach exon1 of GJB2 in case of ARNSHL genetic diagnosis.
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Affiliation(s)
- Atie Kashef
- Genetic Research Center, University of Social Welfare and Rehabilitation Sciences, Tehran, Iran; Deputy of Student Research, University of Social Welfare and Rehabilitation Sciences, Tehran, Iran
| | - Nooshin Nikzat
- Genetic Research Center, University of Social Welfare and Rehabilitation Sciences, Tehran, Iran
| | - Niloofar Bazzazadegan
- Genetic Research Center, University of Social Welfare and Rehabilitation Sciences, Tehran, Iran
| | - Zohreh Fattahi
- Genetic Research Center, University of Social Welfare and Rehabilitation Sciences, Tehran, Iran
| | | | - Maryam Taghdiri
- Genetic Counseling Center, Shiraz Welfare Organization, Fars, Iran
| | | | | | | | - Haleh Habibi
- Genetic Counseling Center, Family Health Clinic, Mobasher Hospital, Hamedan, Iran
| | - Hossein Najmabadi
- Genetic Research Center, University of Social Welfare and Rehabilitation Sciences, Tehran, Iran
| | - Kimia Kahrizi
- Genetic Research Center, University of Social Welfare and Rehabilitation Sciences, Tehran, Iran.
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25
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Shiue I. Chronic diseases and life events accounted for 2-18 % population attributable risks for adult hearing loss: UK Adult Psychiatric Morbidity Survey, 2007. Eur Arch Otorhinolaryngol 2015; 273:93-103. [PMID: 25575844 DOI: 10.1007/s00405-015-3504-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2014] [Accepted: 01/06/2015] [Indexed: 11/29/2022]
Abstract
Links between chronic diseases and hearing loss in adults have emerged. However, previous investigations were not complete, and the role of life events was unclear. Therefore, it was aimed to examine the relationships of common chronic diseases and life events and adult hearing loss in a country-wide and population-based study. Data were retrieved from UK Adult Psychiatric Morbidity Survey, 2007, being cross-sectional, including demographics, self-reported prior health conditions and hearing loss (ever and in the last 12 months), and several major life events. Analyses included Chi square test, t test, logistic regression model, and population attributable risk estimation. People who had prior health conditions including cancer, migraine, dementia, depression, cataracts, chronic bronchitis, allergy, bowel problem, bladder problem, arthritis, muscle problem or skin problem tended to report hearing loss than their counterparts. People who have experienced major life events including post-traumatic stress disorder, serious illness of close relatives, death of family, serious problems with friends, major financial crisis, valuables stolen, being bullied, violence at home, sexual abuse or running away from home were also more likely to experience ever hearing loss problem or that in the last 12 months. 2.0-13.1 % adult hearing loss could be delayed or prevented by managing chronic diseases while 4.1-18.1 % might be delayed or prevented by minimizing the negative effects of life events. Chronic diseases and life events were associated with hearing loss in adults. Better managing lifestyle to minimize detrimental impacts in future health and nursing programs would be suggested.
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Affiliation(s)
- Ivy Shiue
- School of Energy, Geoscience, Infrastructure and Society, Heriot-Watt University, Riccarton, Edinburgh, EH14 4AS, Scotland, UK. .,Owens Institute for Behavioral Research, University of Georgia, Athens, USA.
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26
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Aasen T. Connexins: junctional and non-junctional modulators of proliferation. Cell Tissue Res 2014; 360:685-99. [PMID: 25547217 DOI: 10.1007/s00441-014-2078-3] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2014] [Accepted: 11/14/2014] [Indexed: 12/11/2022]
Abstract
Mounting evidence indicates that dysregulation of gap junctions and their structural subunits-connexins-often occurs in, and sometimes causes, a variety of proliferative disorders, including cancer. Connexin-mediated regulation of cell proliferation is complex and may involve modulation of gap junction intercellular communication (GJIC), hemichannel signalling, or gap junction-independent paths. However, the exact mechanisms linking connexins to proliferation remain poorly defined and a number of contradictory studies report both pro- and anti-proliferative effects, effects that often depend on the cell or tissue type or the microenvironment. The present review covers junctional and non-junctional regulation of proliferation by connexins, with a particular emphasis on their association with cancer.
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Affiliation(s)
- Trond Aasen
- Molecular Pathology Group, Vall d'Hebron Institut de Recerca (VHIR), Universitat Autònoma de Barcelona, Passeig Vall d'Hebron 119-129, Barcelona, 08035, Spain,
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27
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Mroue R, Inman J, Mott J, Budunova I, Bissell MJ. Asymmetric expression of connexins between luminal epithelial- and myoepithelial- cells is essential for contractile function of the mammary gland. Dev Biol 2014; 399:15-26. [PMID: 25500615 DOI: 10.1016/j.ydbio.2014.11.026] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2014] [Revised: 11/27/2014] [Accepted: 11/28/2014] [Indexed: 12/20/2022]
Abstract
Intercellular communication is essential for glandular functions and tissue homeostasis. Gap junctions couple cells homotypically and heterotypically and co-ordinate reciprocal responses between the different cell types. Connexins (Cxs) are the main mammalian gap junction proteins, and the distribution of some Cx subtypes in the heterotypic gap junctions is not symmetrical; in the murine mammary gland, Cx26, Cx30 and Cx32 are expressed only in the luminal epithelial cells and Cx43 is expressed only in myoepithelial cells. Expression of all four Cxs peaks during late pregnancy and throughout lactation suggesting essential roles for these proteins in the functional secretory activity of the gland. Transgenic (Tg) mice over-expressing Cx26 driven by keratin 5 promoter had an unexpected mammary phenotype: the mothers were unable to feed their pups to weaning age leading to litter starvation and demise in early to mid-lactation. The mammary gland of K5-Cx26 female mice developed normally and produced normal levels of milk protein, suggesting a defect in delivery rather than milk production. Because the mammary gland of K5-Cx26 mothers contained excessive milk, we hypothesized that the defect may be in an inability to eject the milk. Using ex vivo three-dimensional mammary organoid cultures, we showed that tissues isolated from wild-type FVB females contracted upon treatment with oxytocin, whereas, organoids from Tg mice failed to do so. Unexpectedly, we found that ectopic expression of Cx26 in myoepithelial cells altered the expression of endogenous Cx43 resulting in impaired gap junction communication, demonstrated by defective dye coupling in mammary epithelial cells of Tg mice. Inhibition of gap junction communication or knock-down of Cx43 in organoids from wild-type mice impaired contraction in response to oxytocin, recapitulating the observations from the mammary glands of Tg mice. We conclude that Cx26 acts as a trans-dominant negative for Cx43 function in myoepithelial cells, highlighting the importance of cell type-specific expression of Cxs for optimal contractile function of the mammary myoepithelium.
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Affiliation(s)
- Rana Mroue
- Helen Diller Family Cancer Research Center, UCSF, 1450 3rd street, San Francisco, CA 94158, USA
| | - Jamie Inman
- Life Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Joni Mott
- Life Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Irina Budunova
- Department of Dermatology, Northwestern University Feinberg School of Medicine, 676 North St. Clair Street, Suite 1600, Chicago, IL 60611, USA
| | - Mina J Bissell
- Life Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA.
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28
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Pavithra A, Selvakumari M, Nityaa V, Sharanya N, Ramakrishnan R, Narasimhan M, Srisailapathy CRS. Autosomal dominant hearing loss resulting from p.R75Q mutation in the GJB2 gene: nonsyndromic presentation in a South Indian family. Ann Hum Genet 2014; 79:76-82. [PMID: 25393658 DOI: 10.1111/ahg.12086] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2014] [Accepted: 09/19/2014] [Indexed: 11/26/2022]
Abstract
Mutations in the GJB2 gene encoding the gap junction protein Connexin 26 have been associated with autosomal recessive as well as dominant nonsyndromic hearing loss. Owing to the involvement of connexins in skin homeostasis, GJB2 mutations have also been associated with syndromic forms of hearing loss showing various skin manifestations. We report an assortatively mating hearing impaired family of south Indian origin with three affected members spread over two generations, having p.R75Q mutation in the GJB2 gene in the heterozygous condition. The inheritance pattern was autosomal dominant with mother and son being affected. Dermatological and histopathologic examinations showed absence of palmoplantar keratoderma. To the best of our knowledge, this is the first report from India on p.R75Q mutation in the GJB2 gene with nonsyndromic hearing loss.
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Affiliation(s)
- Amritkumar Pavithra
- Department of Genetics, Dr. ALM Post Graduate Institute of Basic Medical Sciences, University of Madras, Taramani Campus, Chennai, India
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29
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Pang X, Chai Y, Sun L, Chen D, Chen Y, Zhang Z, Wu H, Yang T. Characterization of spectrum, de novo rate and genotype-phenotype correlation of dominant GJB2 mutations in Chinese hans. PLoS One 2014; 9:e100483. [PMID: 24945352 PMCID: PMC4063943 DOI: 10.1371/journal.pone.0100483] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2014] [Accepted: 05/23/2014] [Indexed: 11/18/2022] Open
Abstract
Dominant mutations in GJB2 may lead to various degrees of sensorineural hearing impairment and/or hyperproliferative epidermal disorders. So far studies of dominant GJB2 mutations were mostly limited to case reports of individual patients and families. In this study, we identified 7 families, 11 subjects with dominant GJB2 mutations by sequencing of GJB2 in 2168 Chinese Han probands with sensorineural hearing impairment and characterized the associated spectrum, de novo rate and genotype-phenotype correlation. We identified p.R75Q, p.R75W and p.R184Q as the most frequent dominant GJB2 mutations among Chinese Hans, which had a very high de novo rate (71% of probands). A majority (10/11) of subjects carrying dominant GJB2 mutations exhibited palmoplantar keratoderma in addition to hearing impairment. In two families segregated with additional c.235delC or p.V37I mutations of GJB2, family members with the compound heterozygous mutations exhibited more severe phenotype than those with single dominant GJB2 mutation. Our study suggested that the high de novo mutation rate gives rise to a significant portion of dominant GJB2 mutations. The severity of the hearing and epidermal phenotypes associated with dominant GJB2 mutations may be modified by additional recessive mutations of GJB2.
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Affiliation(s)
- Xiuhong Pang
- Department of Otorhinolaryngology-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 Otorhinolaryngology-Head and Neck Surgery, Xinhua Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China; Ear Institute, Shanghai Jiaotong University, Shanghai, China
| | - Lianhua Sun
- Department of Otorhinolaryngology-Head and Neck Surgery, Xinhua Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China; Ear Institute, Shanghai Jiaotong University, Shanghai, China
| | - Dongye Chen
- Department of Otorhinolaryngology-Head and Neck Surgery, Xinhua Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China; Ear Institute, Shanghai Jiaotong University, Shanghai, China
| | - Ying Chen
- Department of Otorhinolaryngology-Head and Neck Surgery, Xinhua Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China; Ear Institute, Shanghai Jiaotong University, Shanghai, China
| | - Zhihua Zhang
- Department of Otorhinolaryngology-Head and Neck Surgery, Xinhua Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China; Ear Institute, Shanghai Jiaotong University, Shanghai, China
| | - Hao Wu
- Department of Otorhinolaryngology-Head and Neck Surgery, Xinhua Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China; Ear Institute, Shanghai Jiaotong University, Shanghai, China
| | - Tao Yang
- Department of Otorhinolaryngology-Head and Neck Surgery, Xinhua Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China; Ear Institute, Shanghai Jiaotong University, Shanghai, China
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Al Fahaad H. Keratitis-ichthyosis-deafness syndrome: first affected family reported in the Middle East. Int Med Case Rep J 2014; 7:63-6. [PMID: 24741331 PMCID: PMC3970942 DOI: 10.2147/imcrj.s58432] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Introduction Keratitis–ichthyosis–deafness (KID) syndrome is a rare congenital multisystem disorder affecting certain tissues of ectodermal origin such as epidermis, cochlea, and cornea, leading mainly to palmoplantar hyperkeratosis, ichthyosiform scaling, deafness, and blindness. The author reports for the first time in the Middle East three family members suffering from KID syndrome in the southwestern part of Saudi Arabia. Case presentation Three patients from one family (ages 26, 16, and 14 years) of apparently normal parents, with the two eldest being females and the youngest being male. All three patients were referred from a peripheral hospital to our dermatology clinic due to recurrent cutaneous fungal infections on their trunk, forearms, legs, and nails. On full assessment, they also found to have nearly similar cutaneous problems manifested by palmoplantar hyperkeratosis, generalized ichthyosiform scaling, subungual hyperkeratosis, and nail dystrophies. All patients suffered from total hearing loss in both ears since childhood as confirmed by pure tune audiometry. However, there was no blindness in any case; blepharitis with marked photophobia was the only ocular complaint. All these features are classically suggestive of KID syndrome.
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Affiliation(s)
- Hamad Al Fahaad
- Department of Dermatology, College of Medicine, Najran University, Najran, Saudi Arabia
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American College of Medical Genetics and Genomics guideline for the clinical evaluation and etiologic diagnosis of hearing loss. Genet Med 2014; 16:347-55. [PMID: 24651602 DOI: 10.1038/gim.2014.2] [Citation(s) in RCA: 161] [Impact Index Per Article: 16.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2014] [Accepted: 01/06/2014] [Indexed: 01/24/2023] Open
Abstract
Hearing loss is a common and complex condition that can occur at any age, can be inherited or acquired, and is associated with a remarkably wide array of etiologies. The diverse causes of hearing loss, combined with the highly variable and often overlapping presentations of different forms of hearing loss, challenge the ability of traditional clinical evaluations to arrive at an etiologic diagnosis for many deaf and hard-of-hearing individuals. However, identifying the etiology of a hearing loss may affect clinical management, improve prognostic accuracy, and refine genetic counseling and assessment of the likelihood of recurrence for relatives of deaf and hard-of-hearing individuals. Linguistic and cultural identities associated with being deaf or hard of hearing can complicate access to and the effectiveness of clinical care. These concerns can be minimized when genetic and other health-care services are provided in a linguistically and culturally sensitive manner. This guideline offers information about the frequency, causes, and presentations of hearing loss and suggests approaches to the clinical evaluation of deaf and hard-of-hearing individuals aimed at identifying an etiologic diagnosis and providing informative and effective patient education and genetic counseling.
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Ibáñez MM, Alcalde MM, Jiménez MR, Muñoz MD, Díez-Delgado FJ. An unusual mucocutaneous syndrome with sensorineural deafness due to connexin 26 mutations. Pediatr Dermatol 2013; 30:e138-42. [PMID: 23442195 DOI: 10.1111/pde.12051] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
Mutations of the GJB2 gene, which encodes connexin 26, are related to a range of conditions associated with sensorineural deafness and keratinization disorders. We present the case of a newborn girl with sensorineural deafness, erythematous hyperkeratotic plaques on intertriginous areas, and parakeratosis on the oral and esophageal mucosa. She had an F142L mutation in exon 1 of the GJB2 gene, which was described previously in a patient with a similar phenotype.
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Wonkam A, Noubiap JJN, Bosch J, Dandara C, Toure GB. Heterozygous p.Asp50Asn mutation in the GJB2 gene in two Cameroonian patients with keratitis-ichthyosis-deafness (KID) syndrome. BMC MEDICAL GENETICS 2013; 14:81. [PMID: 23924173 PMCID: PMC3750395 DOI: 10.1186/1471-2350-14-81] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/21/2013] [Accepted: 08/07/2013] [Indexed: 11/10/2022]
Abstract
BACKGROUND Keratitis-Ichthyosis-Deafness (KID) syndrome (OMIM 148210) is a congenital ectodermal defect that consists of an atypical ichthyosiform erythroderma associated with congenital sensorineural deafness. KID appears to be genetically heterogeneous and most cases are caused by GJB2 mutations. Mutations in African patients have been rarely described. CASE PRESENTATION We report on two unrelated Cameroonian individuals affected with sporadic KID, presenting with the classic phenotypic triad. The two patients were heterozygous for the most frequent p.Asp50Asn mutation. This first report in patients from sub-Saharan African origin supports the hypothesis that the occurrence of KID due to p.Asp50Asn mutation in GJB2 seems not to be population specific. CONCLUSIONS Our finding has implication in medical genetic practice, specifically in the molecular diagnosis of KID in Africans. These cases also reveal and emphasize the urgent need to develop appropriate policies to care for patients with rare/orphan diseases in Sub-Saharan Africa, as many of these cases become more and more recognizable.
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Affiliation(s)
- Ambroise Wonkam
- Division of Human Genetics, Department of Clinical Laboratory Sciences, Faculty of Health Sciences, University of Cape Town, Cape Town, South Africa.
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Volo T, Sathiyaseelan T, Astolfi L, Guaran V, Trevisi P, Emanuelli E, Martini A. Hair phenotype in non-syndromic deafness. Int J Pediatr Otorhinolaryngol 2013; 77:1280-5. [PMID: 23751281 DOI: 10.1016/j.ijporl.2013.05.010] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/12/2013] [Revised: 05/08/2013] [Accepted: 05/09/2013] [Indexed: 10/26/2022]
Abstract
The GJB2 gene is located on chromosome 13q12 and it encodes the connexin 26, a transmembrane protein involved in cell-cell attachment of almost all tissues. GJB2 mutations cause autosomal recessive (DFNB1) and sometimes dominant (DFNA3) non-syndromic sensorineural hearing loss. Moreover, it has been demonstrated that connexins are involved in regulation of growth and differentiation of epidermal tissues. Hence, mutations in GJB2 gene, which is responsible for non-syndromic deafness, may be associated with an abnormal skin and hair phenotype. We analyzed hair samples from 96 subjects: a study group of 42 patients with hearing impairments of genetic origin (38 with a non-syndromic form, 4 with a syndromic form), and a control group including 54 people, i.e. 43 patients with other, non-genetic hearing impairments and 11 healthy volunteers aged up to 10 years old. The surface structure of 49 hair samples was normal, whereas in 45 cases it was altered, with a damaged appearance. Two hair samples were considered unclassifiable: one from the patient heterozygotic for the pendrin mutation (Fig. 2C), the other from a patient from Ghana with a R134W mutation (Fig. 2D). Among the 43 altered hair samples, 31 belonged to patients with connexin mutations and the other 12 came from patients without connexin mutations.
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Affiliation(s)
- T Volo
- Otolaryngology and Otosurgery Unit, University Hospital of Padova, Italy.
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Williams P, Memon A, Sinha T, Fryer A. Connecting with connexins. Australas J Dermatol 2013; 54:287-9. [PMID: 23808595 DOI: 10.1111/ajd.12070] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2012] [Accepted: 02/03/2013] [Indexed: 11/28/2022]
Abstract
We describe a case of an 18-year-old woman with congenital sensorineural deafness who presented to the dermatology clinic with asymptomatic thickening of the skin over the palmar aspect of her hands and feet. An examination revealed palmoplantar keratoderma of the palms and soles of the feet with no pseudoainhum. Her father wore a hearing aid and his deafness had been thought to be acquired. Mutation analysis of the connexin 26 gene revealed that she carried a paternally inherited mutation, p.Asp46Glu and a maternally inherited M34T variant. The p.Asp46Glu mutation has been described in a family exhibiting non-syndromic autosomal dominant deafness. Although the M34T variant has been described as a non-pathogenic variant or with a very mild phenotype only, its combination with the p.Asp46Glu mutation may account for her mild cutaneous phenotype with later clinical presentation.
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Affiliation(s)
- Penelope Williams
- Department of Dermatology, Royal Liverpool and Broadgreen Hospital NHS Trust, Southport, UK
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Lin YT, Verma A, Hodgkinson CP. Toll-like receptors and human disease: lessons from single nucleotide polymorphisms. Curr Genomics 2013; 13:633-45. [PMID: 23730203 PMCID: PMC3492803 DOI: 10.2174/138920212803759712] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2012] [Revised: 10/08/2012] [Accepted: 10/08/2012] [Indexed: 12/13/2022] Open
Abstract
Toll-like receptors (TLRs), a large group of proteins which recognize various pathogen-associated molecular patterns, are critical for the normal function of the innate immune system. Following their discovery many single nucleotide polymorphisms within TLRs and components of their signaling machinery have been discovered and subsequently implicated in a wide range of human diseases including atherosclerosis, sepsis, asthma, and immunodeficiency. This review discusses the effect of genetic variation on TLR function and how they may precipitate disease.
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Affiliation(s)
- Yi-Tzu Lin
- Department of Medicine, Duke University Medical Center & Mandel Center for Hypertension and Atherosclerosis Research, Durham, NC 27710, USA
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EMQN Best Practice guidelines for diagnostic testing of mutations causing non-syndromic hearing impairment at the DFNB1 locus. Eur J Hum Genet 2013; 21:1325-9. [PMID: 23695287 PMCID: PMC3798855 DOI: 10.1038/ejhg.2013.83] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
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Mhaske PV, Levit NA, Li L, Wang HZ, Lee JR, Shuja Z, Brink PR, White TW. The human Cx26-D50A and Cx26-A88V mutations causing keratitis-ichthyosis-deafness syndrome display increased hemichannel activity. Am J Physiol Cell Physiol 2013; 304:C1150-8. [PMID: 23447037 DOI: 10.1152/ajpcell.00374.2012] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
Mutations in the human gene encoding connexin 26 (Cx26 or GJB2) cause either nonsyndromic deafness or syndromic deafness associated with skin diseases. That distinct clinical disorders can be caused by different mutations within the same gene suggests that different channel activities influence the ear and skin. Here we use three different expression systems to examine the functional characteristics of two Cx26 mutations causing either mild (Cx26-D50A) or lethal (Cx26-A88V) keratitis-ichthyosis-deafness (KID) syndrome. In either cRNA-injected Xenopus oocytes, transfected HeLa cells, or transfected primary human keratinocytes, we show that both Cx26-D50A and Cx26-A88V form active hemichannels that significantly increase membrane current flow compared with wild-type Cx26. This increased membrane current accelerated cell death in low extracellular calcium solutions and was not due to increased mutant protein expression. Elevated mutant hemichannel currents could be blocked by increased extracellular calcium concentration. These results show that these two mutations exhibit a shared gain of functional activity and support the hypothesis that increased hemichannel activity is a common feature of human Cx26 mutations responsible for KID syndrome.
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Affiliation(s)
- Pallavi V Mhaske
- Department of Physiology and Biophysics, Stony Brook University, Stony Brook, NY 11794, USA
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