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Khan H, Muzaffar F, Salman M, Bashir R, Seo GH, Naz S. Genetic investigations on singleton school aged children reveal novel variants and new candidate genes for hearing loss. Sci Rep 2024; 14:21412. [PMID: 39271758 PMCID: PMC11399343 DOI: 10.1038/s41598-024-71407-1] [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: 03/20/2024] [Accepted: 08/27/2024] [Indexed: 09/15/2024] Open
Abstract
Hearing loss affects around 5% of the global population. Two preliminary studies have described genetic variants in sporadic individuals with hearing loss from Pakistan. Here we extend these studies to determine the spectrum of variants in a cohort of individuals with no previous history of hearing loss. Individuals with hearing loss born to consanguineous couples were identified from special schools. Audiograms were assessed. DNA from participants negative for GJB2 pathogenic variants was subjected to exome sequencing. Data were filtered to include variants with frequencies < 0.01 in the public databases. The effects of the missense variants on respective amino acids were analyzed by using PyMol software. Among the 44 participants, hearing loss was moderate for two individuals; 14 exhibited moderately-severe hearing loss while 25 had a severe degree of hearing loss. Hearing loss was reported to have been progressive in four participants and was currently profound in three participants. Variants were unambiguously identified in 17 genes, of which the majority affected SLC26A4. CDH23, MYO15A and OTOF were other significant contributors. Deleterious variants detected in two genes suggest new associations for hearing loss. Molecular characterization of hearing loss in our cohort revealed high genetic heterogeneity with a 75% diagnostic rate.
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Affiliation(s)
- Hina Khan
- School of Biological Sciences, University of the Punjab, Lahore, Pakistan
| | - Fariha Muzaffar
- School of Biological Sciences, University of the Punjab, Lahore, Pakistan
| | - Midhat Salman
- School of Biological Sciences, University of the Punjab, Lahore, Pakistan
- University of Health Sciences, Lahore, Pakistan
| | - Rasheeda Bashir
- School of Biological Sciences, University of the Punjab, Lahore, Pakistan
- Department of Biotechnology, Lahore College for Women University, Lahore, Pakistan
| | | | - Sadaf Naz
- School of Biological Sciences, University of the Punjab, Lahore, Pakistan.
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Zong YJ, Liu XZ, Tu L, Sun Y. Cytomembrane Trafficking Pathways of Connexin 26, 30, and 43. Int J Mol Sci 2023; 24:10349. [PMID: 37373495 DOI: 10.3390/ijms241210349] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2023] [Revised: 06/12/2023] [Accepted: 06/13/2023] [Indexed: 06/29/2023] Open
Abstract
The connexin gene family is the most prevalent gene that contributes to hearing loss. Connexins 26 and 30, encoded by GJB2 and GJB6, respectively, are the most abundantly expressed connexins in the inner ear. Connexin 43, which is encoded by GJA1, appears to be widely expressed in various organs, including the heart, skin, the brain, and the inner ear. The mutations that arise in GJB2, GJB6, and GJA1 can all result in comprehensive or non-comprehensive genetic deafness in newborns. As it is predicted that connexins include at least 20 isoforms in humans, the biosynthesis, structural composition, and degradation of connexins must be precisely regulated so that the gap junctions can properly operate. Certain mutations result in connexins possessing a faulty subcellular localization, failing to transport to the cell membrane and preventing gap junction formation, ultimately leading to connexin dysfunction and hearing loss. In this review, we provide a discussion of the transport models for connexin 43, connexins 30 and 26, mutations affecting trafficking pathways of these connexins, the existing controversies in the trafficking pathways of connexins, and the molecules involved in connexin trafficking and their functions. This review can contribute to a new way of understanding the etiological principles of connexin mutations and finding therapeutic strategies for hereditary deafness.
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Affiliation(s)
- Yan-Jun Zong
- Department of Otorhinolaryngology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China
| | - Xiao-Zhou Liu
- Department of Otorhinolaryngology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China
| | - Lei Tu
- Division of Gastroenterology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China
| | - Yu Sun
- Department of Otorhinolaryngology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China
- Hubei Province Key Laboratory of Oral and Maxillofacial Development and Regeneration, Wuhan 430022, China
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3
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Naz S. Molecular genetic landscape of hereditary hearing loss in Pakistan. Hum Genet 2021; 141:633-648. [PMID: 34308486 DOI: 10.1007/s00439-021-02320-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2021] [Accepted: 07/17/2021] [Indexed: 01/13/2023]
Abstract
Approximately 14.5 million Pakistani individuals have a hearing loss and half of these cases may be due to genetic causes. Though significant progress has been made in uncovering genetic variants for recessively inherited nonsyndromic deafness, Pendred syndrome, and Usher syndromes, the same is not true for dominantly inherited hearing loss, most syndromic cases and deafness with complex inheritance patterns. Variants of 57 genes have been reported to cause nonsyndromic recessive deafness in Pakistan, though most are rare. Variants of just five genes GJB2, HGF, MYO7A, SLC26A4, and TMC1 together explain 57% of profound deafness while those of GJB2, MYO15A, OTOF, SLC26A4, TMC1, and TMPRSS3 account for 47% of moderate to severe hearing loss. In contrast, although variants of at least 39 genes have been implicated in different deafness syndromes, their prevalence in the population and the spectrum of mutations have not been explored. Furthermore, research on genetics of deafness has mostly focused on individuals from the Punjab province and needs to be extended to other regions of Pakistan. Identifying the genes and their variants causing deafness in all ethnic groups is important as it will pinpoint rare as well as recurrent mutations. This information may ultimately help in offering genetic counseling and future treatments.
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Affiliation(s)
- Sadaf Naz
- School of Biological Sciences, University of the Punjab, Quaid-e-Azam Campus, Lahore, 54590, Pakistan.
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Richard EM, Santos-Cortez RLP, Faridi R, Rehman AU, Lee K, Shahzad M, Acharya A, Khan AA, Imtiaz A, Chakchouk I, Takla C, Abbe I, Rafeeq M, Liaqat K, Chaudhry T, Bamshad MJ, Schrauwen I, Khan SN, Morell RJ, Zafar S, Ansar M, Ahmed ZM, Ahmad W, Riazuddin S, Friedman TB, Leal SM, Riazuddin S. Global genetic insight contributed by consanguineous Pakistani families segregating hearing loss. Hum Mutat 2019; 40:53-72. [PMID: 30303587 PMCID: PMC6296877 DOI: 10.1002/humu.23666] [Citation(s) in RCA: 50] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2018] [Revised: 10/04/2018] [Accepted: 10/07/2018] [Indexed: 12/14/2022]
Abstract
Consanguineous Pakistani pedigrees segregating deafness have contributed decisively to the discovery of 31 of the 68 genes associated with nonsyndromic autosomal recessive hearing loss (HL) worldwide. In this study, we utilized genome-wide genotyping, Sanger and exome sequencing to identify 163 DNA variants in 41 previously reported HL genes segregating in 321 Pakistani families. Of these, 70 (42.9%) variants identified in 29 genes are novel. As expected from genetic studies of disorders segregating in consanguineous families, the majority of affected individuals (94.4%) are homozygous for HL-associated variants, with the other variants being compound heterozygotes. The five most common HL genes in the Pakistani population are SLC26A4, MYO7A, GJB2, CIB2 and HGF, respectively. Our study provides a profile of the genetic etiology of HL in Pakistani families, which will allow for the development of more efficient genetic diagnostic tools, aid in accurate genetic counseling, and guide application of future gene-based therapies. These findings are also valuable in interpreting pathogenicity of variants that are potentially associated with HL in individuals of all ancestries. The Pakistani population, and its infrastructure for studying human genetics, will continue to be valuable to gene discovery for HL and other inherited disorders.
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Affiliation(s)
- Elodie M. Richard
- Department of Otorhinolaryngology Head & Neck Surgery, School of Medicine, University of Maryland, Baltimore, MD, 21201, USA
| | - Regie LP. Santos-Cortez
- Center for Statistical Genetics, Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, 77030, USA
| | - Rabia Faridi
- Laboratory of Molecular Genetics, National Institute on Deafness and Other Communication Disorders, National Institutes of Health, Bethesda, MD, 20892, USA
- National Center for Excellence in Molecular Biology, University of the Punjab, Lahore 53700, Pakistan
| | - Atteeq U. Rehman
- Laboratory of Molecular Genetics, National Institute on Deafness and Other Communication Disorders, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Kwanghyuk Lee
- Center for Statistical Genetics, Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, 77030, USA
| | - Mohsin Shahzad
- Department of Otorhinolaryngology Head & Neck Surgery, School of Medicine, University of Maryland, Baltimore, MD, 21201, USA
- Shaheed Zulfiqar Ali Bhutto Medical University, Pakistan Institute of Medical Sciences, Islamabad, 44000, Pakistan
| | - Anushree Acharya
- Center for Statistical Genetics, Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, 77030, USA
| | - Asma A. Khan
- National Center for Excellence in Molecular Biology, University of the Punjab, Lahore 53700, Pakistan
| | - Ayesha Imtiaz
- Laboratory of Molecular Genetics, National Institute on Deafness and Other Communication Disorders, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Imen Chakchouk
- Center for Statistical Genetics, Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, 77030, USA
| | - Christina Takla
- Laboratory of Molecular Genetics, National Institute on Deafness and Other Communication Disorders, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Izoduwa Abbe
- Center for Statistical Genetics, Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, 77030, USA
| | - Maria Rafeeq
- National Center for Excellence in Molecular Biology, University of the Punjab, Lahore 53700, Pakistan
| | - Khurram Liaqat
- Department of Biotechnology, Faculty of Biological Sciences, Quaid-i-Azam University, Islamabad, 45320, Pakistan
| | - Taimur Chaudhry
- Laboratory of Molecular Genetics, National Institute on Deafness and Other Communication Disorders, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Michael J. Bamshad
- Department of Genome Sciences, University of Washington, Seattle, WA 98195, USA
| | | | - Isabelle Schrauwen
- Center for Statistical Genetics, Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, 77030, USA
| | - Shaheen N. Khan
- National Center for Excellence in Molecular Biology, University of the Punjab, Lahore 53700, Pakistan
| | - Robert J. Morell
- The Genomics and Computational Biology Core, National Institute on Deafness and Other Communication Disorders, National Institutes of Health, Bethesda, MD, 20892
| | - Saba Zafar
- Institute of Molecular Biology and Biotechnology, Bahauddin Zakariya University, Multan, 59300, Pakistan
| | - Muhammad Ansar
- Department of Biotechnology, Faculty of Biological Sciences, Quaid-i-Azam University, Islamabad, 45320, Pakistan
| | - Zubair M. Ahmed
- Department of Otorhinolaryngology Head & Neck Surgery, School of Medicine, University of Maryland, Baltimore, MD, 21201, USA
| | - Wasim Ahmad
- Department of Biotechnology, Faculty of Biological Sciences, Quaid-i-Azam University, Islamabad, 45320, Pakistan
| | - Sheik Riazuddin
- Shaheed Zulfiqar Ali Bhutto Medical University, Pakistan Institute of Medical Sciences, Islamabad, 44000, Pakistan
- Allama Iqbal Medical College, University of Health Sciences, Lahore, 54500, Pakistan
| | - Thomas B. Friedman
- Laboratory of Molecular Genetics, National Institute on Deafness and Other Communication Disorders, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Suzanne M. Leal
- Center for Statistical Genetics, Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, 77030, USA
| | - Saima Riazuddin
- Department of Otorhinolaryngology Head & Neck Surgery, School of Medicine, University of Maryland, Baltimore, MD, 21201, USA
- Shaheed Zulfiqar Ali Bhutto Medical University, Pakistan Institute of Medical Sciences, Islamabad, 44000, Pakistan
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Shaikh H, Waryah AM, Narsani AK, Iqbal M, Shahzad M, Waryah YM, Shaikh N, Mahmood A. Genetic Testing of Non-familial Deaf Patients for CIB2 and GJB2 Mutations: Phenotype and Genetic Counselling. Biochem Genet 2017; 55:410-420. [PMID: 29086887 DOI: 10.1007/s10528-017-9828-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2017] [Accepted: 09/19/2017] [Indexed: 02/02/2023]
Abstract
CIB2 and GJB2 genes variants contribute significantly in familial cases of prelingual recessive hearing loss (HL). This study was aimed to determine the CIB2 and GJB2 variants and associated phenotype in 150 non-familial individuals with HL. After getting informed consent, 150 non-familial deaf patients were enrolled and blood samples were obtained for DNA extraction. Pure tone air conduction audiometry was performed. Coding exons of CIB2 and GJB2 genes were Sanger sequenced. A tetra primer ARMS assay was developed for recurrent CIB2 variant. Four bi-allelic GJB2 variants, c.71G>A p.(Trp24*), c.231G>A p.(Trp77*), c.235delC p.(Leu79Cysfs3*) and c.35delG p.(Gly11Leufs24*), were found in nine hearing impaired individuals. We also found four homozygotes and five carriers of c.380G>A p. (Arg127His) variant of controversial clinical significance. CIB2 sequencing revealed single recurrent variant c.272T>C p. (Phe91Ser) segregating with HL in ten individuals. Among our patients, c.71G>A (p.Trp24*) was the most common variant, accounted for 45% of GJB2 variants. Two known GJB2 variants, c.235delC p. (Leu79Cysfs3*) and c.310del14 p. (Lys105Argfs2*), are reported here for the first time in Pakistani population. Our data further support the benign nature of c.380G>A p. (Arg127His) variant. For CIB2, c.272T>C p. (Phe91Ser) is the second common cause of HL among our sporadic cases. Phenotypically, in our patients, individuals homozygous for GJB2 variants had profound HL, whereas CIB2 homozygotes had severe to profound prelingual HL. Our results suggest that GJB2 and CIB2 are common cause of HL in different Pakistani ethnicities.
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Affiliation(s)
- Hina Shaikh
- Molecular Biology and Genetics Department, Medical Research Center, Liaquat University of Medical and Health Sciences, Jamshoro, Pakistan
| | - Ali M Waryah
- Molecular Biology and Genetics Department, Medical Research Center, Liaquat University of Medical and Health Sciences, Jamshoro, Pakistan.
| | - Ashok K Narsani
- Institute of Ophthalmology, Liaquat University of Medical and Health Sciences, Jamshoro, Pakistan
| | - Muhammad Iqbal
- Department of Biochemistry and Biotechnology, Islamia University, Bahawalpur, Pakistan
| | - Mohsin Shahzad
- Department of Molecular Biology, Shaheed Zulfiqar Ali Bhutto Medical University, Islamabad, Pakistan
| | - Yar M Waryah
- Molecular Biology and Genetics Department, Medical Research Center, Liaquat University of Medical and Health Sciences, Jamshoro, Pakistan
| | - Naila Shaikh
- Molecular Biology and Genetics Department, Medical Research Center, Liaquat University of Medical and Health Sciences, Jamshoro, Pakistan
| | - Amber Mahmood
- Molecular Biology and Genetics Department, Medical Research Center, Liaquat University of Medical and Health Sciences, Jamshoro, Pakistan
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Wang R, Han S, Khan A, Zhang X. Molecular Analysis of Twelve Pakistani Families with Nonsyndromic or Syndromic Hearing Loss. Genet Test Mol Biomarkers 2017; 21:316-321. [PMID: 28281779 DOI: 10.1089/gtmb.2016.0328] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
AIM To investigate the causative genetic mutations in 12 Pakistani families with nonsyndromic or syndromic hearing loss. METHODS Mutations in the most common causative gene for hearing loss, GJB2, were evaluated by Sanger sequencing. Targeted next-generation sequencing or whole-exome sequencing was used to analyze the genomic DNA samples from 11 probands with hearing loss. Sanger sequencing was performed to verify all identified variants. RESULTS We found pathogenic, or likely to be pathogenic, mutations in all 12 families, including six known mutations in GJB2, SLC26A4, LHFPL5, and USH2A and eight novel mutations in ESPN, MYO7A, LRTOMT, PCDH15, USH2A, or EPS8L2. Notably, four compound heterozygous mutations in the MYO7A and USH2A genes were detected in two consanguineous families. In addition, the novel frameshift mutation in EPS8L2 was first documented in Pakistan. CONCLUSIONS Our study increases the spectrum of mutations associated with hearing loss in the Pakistani population. In addition, our study highlights the fact that compound heterozygous mutations, although rare, can occur in consanguineous families.
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Affiliation(s)
- Rongrong Wang
- 1 Institute of Basic Medical Sciences Chinese Academy of Medical Sciences, McKusick-Zhang Center for Genetic Medicine, School of Basic Medicine Peking Union Medical College , Beijing, China
| | - Shirui Han
- 2 The Research Center for Medical Genomics, China Medical University , Shenyang, China
| | - Amjad Khan
- 2 The Research Center for Medical Genomics, China Medical University , Shenyang, China
| | - Xue Zhang
- 1 Institute of Basic Medical Sciences Chinese Academy of Medical Sciences, McKusick-Zhang Center for Genetic Medicine, School of Basic Medicine Peking Union Medical College , Beijing, China
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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.
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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
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Shafique S, Siddiqi S, Schraders M, Oostrik J, Ayub H, Bilal A, Ajmal M, Seco CZ, Strom TM, Mansoor A, Mazhar K, Shah STA, Hussain A, Azam M, Kremer H, Qamar R. Genetic spectrum of autosomal recessive non-syndromic hearing loss in Pakistani families. PLoS One 2014; 9:e100146. [PMID: 24949729 PMCID: PMC4065008 DOI: 10.1371/journal.pone.0100146] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2014] [Accepted: 05/22/2014] [Indexed: 12/01/2022] Open
Abstract
The frequency of inherited bilateral autosomal recessive non-syndromic hearing loss (ARNSHL) in Pakistan is 1.6/1000 individuals. More than 50% of the families carry mutations in GJB2 while mutations in MYO15A account for about 5% of recessive deafness. In the present study a cohort of 30 ARNSHL families was initially screened for mutations in GJB2 and MYO15A. Homozygosity mapping was performed by employing whole genome single nucleotide polymorphism (SNP) genotyping in the families that did not carry mutations in GJB2 or MYO15A. Mutation analysis was performed for the known ARNSHL genes present in the homozygous regions to determine the causative mutations. This allowed the identification of a causative mutation in all the 30 families including 9 novel mutations, which were identified in 9 different families (GJB2 (c.598G>A, p.Gly200Arg); MYO15A (c.9948G>A, p.Gln3316Gln; c.3866+1G>A; c.8767C>T, p.Arg2923* and c.8222T>C, p.Phe2741Ser), TMC1 (c.362+18A>G), BSND (c.97G>C, p.Val33Leu), TMPRSS3 (c.726C>G, p.Cys242Trp) and MSRB3 (c.20T>G, p.Leu7Arg)). Furthermore, 12 recurrent mutations were detected in 21 other families. The 21 identified mutations included 10 (48%) missense changes, 4 (19%) nonsense mutations, 3 (14%) intronic mutations, 2 (9%) splice site mutations and 2 (9%) frameshift mutations. GJB2 accounted for 53% of the families, while mutations in MYO15A were the second most frequent (13%) cause of ARNSHL in these 30 families. The identification of novel as well as recurrent mutations in the present study increases the spectrum of mutations in known deafness genes which could lead to the identification of novel founder mutations and population specific mutated deafness genes causative of ARNSHL. These results provide detailed genetic information that has potential diagnostic implication in the establishment of cost-efficient allele-specific analysis of frequently occurring variants in combination with other reported mutations in Pakistani populations.
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Affiliation(s)
- Sobia Shafique
- COMSATS Institute of Information Technology, Park Road, Islamabad, Pakistan
| | - Saima Siddiqi
- Institute of Biomedical and Genetic Engineering (IBGE), Islamabad, Pakistan
| | - Margit Schraders
- Department of Otorhinolaryngology, Hearing and Genes, Radboud University Medical Center, Nijmegen, The Netherlands
- Nijmegen Centre for Molecular Life Sciences, Radboud University Medical Center, Nijmegen, The Netherlands
- Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Jaap Oostrik
- Department of Otorhinolaryngology, Hearing and Genes, Radboud University Medical Center, Nijmegen, The Netherlands
- Nijmegen Centre for Molecular Life Sciences, Radboud University Medical Center, Nijmegen, The Netherlands
- Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Humaira Ayub
- COMSATS Institute of Information Technology, Park Road, Islamabad, Pakistan
| | - Ammad Bilal
- Simon Fraser University, Vancouver, British Colombia, Canada
| | - Muhammad Ajmal
- COMSATS Institute of Information Technology, Park Road, Islamabad, Pakistan
| | - Celia Zazo Seco
- Department of Otorhinolaryngology, Hearing and Genes, Radboud University Medical Center, Nijmegen, The Netherlands
- Nijmegen Centre for Molecular Life Sciences, Radboud University Medical Center, Nijmegen, The Netherlands
- Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Tim M. Strom
- Institute of Human Genetics, Helmholtz Zentrum München, German Research Center for Environmental Health, Neuherberg, Germany
| | - Atika Mansoor
- Institute of Biomedical and Genetic Engineering (IBGE), Islamabad, Pakistan
| | - Kehkashan Mazhar
- Institute of Biomedical and Genetic Engineering (IBGE), Islamabad, Pakistan
| | - Syed Tahir A. Shah
- COMSATS Institute of Information Technology, Park Road, Islamabad, Pakistan
| | - Alamdar Hussain
- COMSATS Institute of Information Technology, Park Road, Islamabad, Pakistan
| | - Maleeha Azam
- COMSATS Institute of Information Technology, Park Road, Islamabad, Pakistan
| | - Hannie Kremer
- Department of Otorhinolaryngology, Hearing and Genes, Radboud University Medical Center, Nijmegen, The Netherlands
- Nijmegen Centre for Molecular Life Sciences, Radboud University Medical Center, Nijmegen, The Netherlands
- Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center, Nijmegen, The Netherlands
- Department of Human Genetics, Radboud university medical center, Nijmegen, The Netherlands
- * E-mail: (HK); (RQ)
| | - Raheel Qamar
- COMSATS Institute of Information Technology, Park Road, Islamabad, Pakistan
- Al-Nafees Medical College & Hospital, Isra University, Islamabad, Pakistan
- * E-mail: (HK); (RQ)
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