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GJB2 mutations in Iranian Azeri population with autosomal recessive nonsyndromic hearing loss (ARNSHL): First report of c.238 C>A mutation in Iran. J Clin Lab Anal 2021; 35:e24024. [PMID: 34581455 PMCID: PMC8605150 DOI: 10.1002/jcla.24024] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2021] [Revised: 09/09/2021] [Accepted: 09/14/2021] [Indexed: 12/18/2022] Open
Abstract
Objective Autosomal‐recessive nonsyndromic hearing loss (ARNSHL) is a heterogeneous genetic disorder. Mutations in the gap junction protein beta 2 (GJB2) gene, encoding connexin 26, are a significant cause of ARNSHL in different ethnic groups. This study aimed to identify the frequency and type of GJB2 mutations in the Iranian Azeri population. Methods Fifty unrelated families presenting ARNSHL in Ardabil Province, the northwest of Iran, were studied to determine the frequency and type of GJB2 mutations leading to ARNSHL. ARMS‐PCR screened all DNA samples to detect c.35delG; p. Gly12Val mutation. In addition, normal samples for c.35delG; p. Gly12Val were analyzed by direct sequencing for other GJB2 mutations. Result Of the fifty families, 13 (26%) showed a GJB2 gene mutation, with c.35delG; p. Gly12Val mutation was the most prevalent one that occurred in eight (61.5%) out of the 13 families. Of the families, two were homozygous for c.358‐360delGAC; p. Glu120del mutation, and one was homozygous for c.290dupA; p. Tyr97Ter and c.299–300delAT; p. His100Arg mutations. Also, we detected a novel mutation, c.238C>A; p. Gln80lys, in one of the families. Conclusion Our findings are comparable to previous studies, indicating c.35d3lG; p. Gly12Val mutation in the GJB2 gene is the most common cause of GJB2‐related hearing loss in the Iranian Azeri population. Furthermore, our study highlights the significance of ARNSHL screening programs of live births based on local population data in Iran.
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Affiliation(s)
| | - Mohammad Panahi
- Department of Medical Biotechnology, Faculty of Advanced Medical Sciences, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Bahareh Rahimi
- Department of Medical Biotechnology, Faculty of Allied Medical Sciences, Iran University of Medical Sciences, Tehran, Iran
| | - Haleh Mokabber
- Medical Genetics and Pathology, Ardabil University of Medical Sciences, Ardabil, Iran
| | - Reza Farajollahi
- Medical Genetics and Pathology, Ardabil University of Medical Sciences, Ardabil, Iran.,Ardabil Welfare Organization, Ardabil, Iran
| | - Behzad Davarnia
- Medical Genetics and Pathology, Ardabil University of Medical Sciences, Ardabil, Iran
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Assessment of Gap Junction Protein Beta-2 rs3751385 Gene Polymorphism in Psoriasis Vulgaris. J Clin Med Res 2019; 11:642-650. [PMID: 31523338 PMCID: PMC6731047 DOI: 10.14740/jocmr3845] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2019] [Accepted: 06/25/2019] [Indexed: 02/05/2023] Open
Abstract
Background Gap junction protein beta 2 (GJB2) upregulation in psoriasis transcriptome analysis as well as connexin 26 (Cx26, encoded by GJB2) expression upregulation in psoriatic plaques has already been substantiated. GJB2 rs72474224 and rs3751385 have been correlated with psoriasis vulgaris incidence in Chinese populations. Here we study the effect of rs3751385 in patients suffering from psoriasis vulgaris in a Caucasian Greek population at the prefecture of Thrace in Northern Greece. Methods One hundred and seventy-three (111 males and 62 females) psoriatic patients (108 were of early-onset psoriasis) and 171 matched controls were included in the study. Genomic DNA was extracted from peripheral blood leukocytes and genotyping was carried out by polymerase chain reaction-restriction-fragment length polymorphism (PCR-RFLP). Results A statistically significant lower frequency of C/T genotype in late-onset male psoriasis vulgaris (P = 0.029) as well as of T allele in female early-onset psoriasis vulgaris (P = 0.049) were ascertained. Conclusions On condition that all other genetic or environmental factors remain stable, the existence and possible interaction between GJB2 rs3751385 C and T alleles in male psoriatic patients may be considered as protective gene component against late-onset psoriasis appearance, while presence of the T allele in female might block the histogenetic mechanisms of early-onset psoriasis lesions.
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Affiliation(s)
- Elli-Anna Stylianaki
- Department of Biology, Faculty of Medicine, Democritus University of Thrace, Alexandroupolis, Greece
| | - Anthony Karpouzis
- Department of Dermatology, Faculty of Medicine, Democritus University of Thrace, Alexandroupolis, Greece
| | - Gregory Tripsianis
- Department of Medical Statistics, Faculty of Medicine, Democritus University of Thrace, Alexandroupolis, Greece
| | - Stavroula Veletza
- Department of Biology, Faculty of Medicine, Democritus University of Thrace, Alexandroupolis, Greece
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Update of spectrum c.35delG and c.‐23+1G>A mutations on the
GJB2
gene in individuals with autosomal recessive nonsyndromic hearing loss. Ann Hum Genet 2018; 83:1-10. [DOI: 10.1111/ahg.12284] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2017] [Revised: 08/01/2018] [Accepted: 08/06/2018] [Indexed: 12/31/2022]
Affiliation(s)
- Fatemeh Azadegan‐Dehkordi
- Cellular and Molecular Research Center, Basic Health Sciences Institute Shahrekord University of Medical Sciences Shahrekord Iran
| | - Reza Ahmadi
- Clinical Biochemistry Research Center, Basic Health Sciences Institute Shahrekord University of Medical Sciences Shahrekord Iran
| | - Mahbobeh Koohiyan
- Medical Plants Research Center, Basic Health Sciences Institute Shahrekord University of Medical Sciences Shahrekord Iran
| | - Morteza Hashemzadeh‐Chaleshtori
- Cellular and Molecular Research Center, Basic Health Sciences Institute Shahrekord University of Medical Sciences Shahrekord Iran
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Genetic Aetiology of Nonsyndromic Hearing Loss in Moravia-Silesia. MEDICINA-LITHUANIA 2018; 54:medicina54020028. [PMID: 30344259 PMCID: PMC6037260 DOI: 10.3390/medicina54020028] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 03/28/2018] [Revised: 05/01/2018] [Accepted: 05/02/2018] [Indexed: 11/16/2022]
Abstract
BACKGROUND AND OBJECTIVE Hearing loss is the most common sensory deficit in humans. The aim of this study was to clarify the genetic aetiology of nonsyndromic hearing loss in the Moravian-Silesian population of the Czech Republic. PATIENTS AND METHODS This study included 200 patients (93 males, 107 females, mean age 16.9 years, ranging from 4 months to 62 years) with nonsyndromic sensorineural hearing loss. We screened all patients for mutations in GJB2 and the large deletion del(GJB6-D13S1830). We performed further screening for additional genes (SERPINB6, TMIE, COCH, ESPN, ACTG1, KCNQ4, and GJB3) with Sanger sequencing on a subset of patients that were negative for GJB2 mutations. RESULTS We detected biallelic GJB2 mutations in 44 patients (22%). Among these patients, 63.6%, 9.1% and 2.3% exhibited homozygous c.35delG, p.Trp24*, and p.Met34Thr mutations, respectively. The remaining 25% of these patients exhibited compound heterozygous c.35delG, c.-23+1G>A, p.Trp24*, p.Val37Ile, p.Met34Thr, p.Leu90Pro, c.235delC, c.313_326del14, p.Ser139Asn, and p.Gly147Leu mutations. We found a monoallelic GJB2 mutation in 12 patients (6.6%). We found no pathogenic mutations in the other tested genes. Conclusions: One fifth of our cohort had deafness related to GJB2 mutations. The del(GJB6-D13S1830), SERPINB6, TMIE, COCH, ESPN, ACTG1, GJB3, and KCNQ4 mutations were infrequently associated with deafness in the Moravian-Silesian population. Therefore, we suggest that del(GJB6-D13S1830) testing should be performed only when patients with deafness carry the monoallelic GJB2 mutation.
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Affiliation(s)
- Pavlina Plevova
- Department of Medical Genetics, University Hospital Ostrava, 17. listopadu 1790, 708 52 Ostrava, Czech Republic.
| | - Petra Tvrda
- Department of Medical Genetics, University Hospital Ostrava, 17. listopadu 1790, 708 52 Ostrava, Czech Republic.
| | - Martina Paprskarova
- Department of Medical Genetics, University Hospital Ostrava, 17. listopadu 1790, 708 52 Ostrava, Czech Republic.
| | - Petra Turska
- Department of Medical Genetics, University Hospital Ostrava, 17. listopadu 1790, 708 52 Ostrava, Czech Republic.
| | - Barbara Kantorova
- Department of Medical Genetics, University Hospital Ostrava, 17. listopadu 1790, 708 52 Ostrava, Czech Republic.
| | - Eva Mrazkova
- Department of Epidemiology and Public Health, Faculty of Medicine, University of Ostrava, Syllabova 19, 703 00 Ostrava, Zábřeh, Czech Republic.
- Department of Otorhinolaryngology, Hospital of Havířov, Dělnická 1132/24, 736 01 Havířov, Czech Republic.
| | - Jana Zapletalova
- Department of Medical Biophysics, Faculty of Medicine and Dentistry, Palacky University Olomouc, Hnevotinska 3, 775 15 Olomouc, Czech Republic.
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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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Single nucleotide polymorphisms of the GJB2 and GJB6 genes are associated with autosomal recessive nonsyndromic hearing loss. BIOMED RESEARCH INTERNATIONAL 2015; 2015:318727. [PMID: 26075227 PMCID: PMC4449875 DOI: 10.1155/2015/318727] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/07/2014] [Accepted: 03/01/2015] [Indexed: 12/02/2022]
Abstract
Single nucleotide polymorphisms (SNPs) are important markers in many studies that link DNA sequence variations to phenotypic changes; such studies are expected to advance the understanding of human physiology and elucidate the molecular basis of diseases. The DFNB1 locus, which contains the GJB2 and GJB6 genes, plays a key role in nonsyndromic hearing loss. Previous studies have identified important mutations in this locus, but the contribution of SNPs in the genes has not yet been much investigated. The aim of this study was to investigate the association of nine polymorphisms located within the DFNB1 locus with the occurrence of autosomal recessive nonsyndromic hearing loss (ARNSHL). The SNPs rs3751385 (C/T), rs7994748 (C/T), rs7329857 (C/T), rs7987302 (G/A), rs7322538 (G/A), rs9315400 (C/T), rs877098 (C/T), rs945369 (A/C), and rs7333214 (T/G) were genotyped in 122 deaf patients and 132 healthy controls using allele-specific PCR. There were statistically significant differences between patients and controls, in terms of allelic frequencies in the SNPs rs3751385, rs7994748, rs7329857, rs7987302, rs945369, and rs7333214 (P < 0.05). No significant differences between the two groups were observed for rs7322538, rs9315400, and rs877098. Our results suggest that SNPs present in the GJB2 and GJB6 genes may have an influence on ARNSHL in humans.
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GJB2-associated hearing loss: Systematic review of worldwide prevalence, genotype, and auditory phenotype. Laryngoscope 2013; 124:E34-53. [DOI: 10.1002/lary.24332] [Citation(s) in RCA: 183] [Impact Index Per Article: 16.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/10/2013] [Indexed: 12/17/2022]
Affiliation(s)
- Dylan K. Chan
- Department of Otolaryngology-Head and Neck Surgery; University of California; San Francisco U.S.A
| | - Kay W. Chang
- Department of Otolaryngology-Head and Neck Surgery; Stanford University School of Medicine; Stanford California U.S.A
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8
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Prevalence of DFNB1 mutations in Slovak patients with non-syndromic hearing loss. Int J Pediatr Otorhinolaryngol 2012; 76:400-3. [PMID: 22281373 DOI: 10.1016/j.ijporl.2011.12.020] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/24/2011] [Accepted: 12/20/2011] [Indexed: 11/24/2022]
Abstract
OBJECTIVES Non-syndromic hearing loss is one of the most common genetically determined diseases in human. The incidence is approximately 1:700 and most of the cases are caused by mutations in specific locus - DFNB1, which contains two genes -GJB2 and GJB6. For the GJB2 gene following mutations are most prevalent in specific populations - 35delG, 235delC, W24X and 167delT for Caucasians, Asians, Indians and Ashkenazi Jews, respectively. Large deletions are common in GJB6 gene. Many other mutations and polymorphisms were found in DFNB1 focused non-syndromic hearing loss studies thus the establishment of optimal screening protocol should be based on population specific mutation screening studies and is an objective in our study. PATIENTS AND METHODS In our study samples from 273 non-syndromic hearing loss patients were screened for mutations in coding and non-coding part of GJB2 gene and large deletion in GJB6 gene - del(GJB6-D13S1830). RESULTS Causal mutation on both chromosomes was detected in 24.57% of patients, another 9.9% carried causal mutation on one chromosome. Totally 7 polymorphisms: V27I, M34T, F83L, 354 C→T, R127H, V153I, 684 C→A and 11 causal mutations: IVS1+1 G→A, 35delG, W24X, V37I, E47X, 167delT, V84M, L90P, 310del14, 333-334delAA, R184Q were detected. No patient carried the GJB6 deletion mutation (del(GJB6-D13S1830)). CONCLUSION According to our results sequencing of GJB2 coding regions and IVS1+1G→A specific detection should explain approximately 25% of sporadic NSHL cases and these two tests are relevant for use as routine screening protocol for NSHL in Slovakia. The GJB6 del(GJB6-D13S1830) mutation was not detected in any of NSHL samples therefore it is not necessary to implement it in our routine screening protocol.
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Affiliation(s)
- Gabriel Minárik
- Institute of Molecular Biomedicine, Comenius University Faculty of Medicine, Bratislava, Slovakia.
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9
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Spectrum of GJB2 (Cx26) gene mutations in Iranian Azeri patients with nonsyndromic autosomal recessive hearing loss. Int J Pediatr Otorhinolaryngol 2012; 76:268-71. [PMID: 22172221 DOI: 10.1016/j.ijporl.2011.11.019] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/24/2011] [Revised: 11/16/2011] [Accepted: 11/18/2011] [Indexed: 10/14/2022]
Abstract
OBJECTIVE Hereditary hearing impairment is a genetically heterogeneous disorder. In spite of this, mutations in the GJB2 gene, encoding connexin 26 (Cx26), are a major cause of nonsyndromic recessive hearing loss in many countries and are largely dependent on ethnic groups. The purpose of our study was to characterize the type and prevalence of GJB2 mutations among Azeri population of Iran. METHODS Fifty families presenting autosomal recessive nonsyndromic hearing loss from Ardabil province of Iran were studied for mutations in GJB2 gene. All DNA samples were screened for c.35delG mutation by ARMS PCR. Samples from patients who were normal for c.35delG were analyzed for the other variations in GJB2 by direct sequencing. In the absence of mutation detection, GJB6 was screened for the del(GJB6-D13S1830) and del(GJB6-D13S1854). RESULT Thirteen families demonstrated alteration in the Cx26 (26%). The 35delG mutation was the most common one, accounting for 69.2% (9 out of 13 families). All the detected families were homozygous for this mutation. Two families were homozygous for delE120 and 299-300delAT mutations. We also identified a novel mutation: c.463-464 delTA in 2 families resulting in a frame shift mutation. CONCLUSION Our results suggest that c.35delG mutation in the GJB2 gene is the most important cause of GJB2 related deafness in Iranian Azeri population.
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Affiliation(s)
- Behzad Davarnia
- Genetics Research Centre, University of Social Welfare and Rehabilitation Sciences, Tehran, Iran
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Frequence and the mutation spectrum of GJB2-related hearing loss in children of Dagestan as compared with the central European part of Russia. Biophysics (Nagoya-shi) 2010. [DOI: 10.1134/s0006350910030176] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
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Two Novel Missense Mutations in the Connexin 26 Gene in Turkish Patients with Nonsyndromic Hearing Loss. Biochem Genet 2009; 48:248-56. [DOI: 10.1007/s10528-009-9314-7] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2008] [Accepted: 08/21/2009] [Indexed: 11/28/2022]
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GJB2 (connexin 26) gene mutations in Moroccan patients with autosomal recessive non-syndromic hearing loss and carrier frequency of the common GJB2-35delG mutation. Int J Pediatr Otorhinolaryngol 2007; 71:1239-45. [PMID: 17553572 DOI: 10.1016/j.ijporl.2007.04.019] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/02/2007] [Revised: 04/20/2007] [Accepted: 04/24/2007] [Indexed: 10/23/2022]
Abstract
OBJECTIVE Mutations in the connexin 26 gene (GJB2), which encodes a gap-junction protein expressed in the inner ear, have been shown to be responsible for a major part of autosomal recessive non-syndromic hearing loss in Caucasians. The aim of our study was to determine the prevalence and spectrum of GJB2 mutations, including the (GJB6-D13S1830) deletion, in Moroccan patients and estimate the carrier frequency of the 35delG mutation in the general population. METHODS Genomic DNA was isolated from 81 unrelated Moroccan familial cases with moderate to profound autosomal recessive non-syndromic hearing loss and 113 Moroccan control individuals. Molecular studies were performed using PCR-Mediated Site Directed Mutagenesis assay, PCR and direct sequencing to screen for GJB2, 35delG and del(GJB6-D13S1830) mutations. RESULTS GJB2 mutations were found in 43.20% of the deaf patients. Among these patients 35.80% were 35delG/35delG homozygous, 2.47% were 35delG/wt heterozygous, 3.70% were V37I/wt heterozygous, and 1 patient was E47X/35delG compound heterozygous. None of the patients with one or no GJB2 mutation displayed the common (GJB6-D13S1830) deletion. We found also that the carrier frequency of GJB2-35delG in the normal Moroccan population is 2.65%. CONCLUSIONS These findings indicate that the GJB2-35delG mutation is the major cause of autosomal recessive non-syndromic hearing loss in Moroccan population. Two other mutations were also detected (V37I and E47X), in agreement with similar studies in other populations showing heterogeneity in the frequencies and types of mutation in connexin 26 gene.
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Affiliation(s)
- Omar Abidi
- Laboratoire de Génétique Humaine, Département de Recherche Scientifique, Institut Pasteur, Casablanca, Morocco
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Abstract
Non-syndromic deafness is a paradigm of genetic heterogeneity with 85 loci and 39 nuclear disease genes reported so far. Autosomal-recessive genes are responsible for about 80% of the cases of hereditary non-syndromic deafness of pre-lingual onset with 23 different genes identified to date. In the present article, we review these 23 genes, their function, and their contribution to genetic deafness in different populations. The wide range of functions of these DFNB genes reflects the heterogeneity of the genes involved in hearing and hearing loss. Several of these genes are involved in both recessive and dominant deafness, or in both non-syndromic and syndromic deafness. Mutations in the GJB2 gene encoding connexin 26 are responsible for as much as 50% of pre-lingual, recessive deafness. By contrast, mutations in most of the other DFNB genes have so far been detected in only a small number of families, and their contribution to deafness on a population scale might therefore be limited. Identification of all genes involved in hereditary hearing loss will help in our understanding of the basic mechanisms underlying normal hearing, in early diagnosis and therapy.
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Affiliation(s)
- M B Petersen
- Department of Genetics, Institute of Child Health, Aghia Sophia Children's Hospital, Athens, Greece.
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