Association of GJB2 gene mutation with cochlear implant performance in genetic non-syndromic hearing loss

AbstractObjective:GJB2 gene mutations are highly prevalent in pre-lingual hearing loss patients from China. Pre-lingual deafness is a sensorineural disorder that can only be treated with cochlear implantation.Method:The prevalence of GJB2 gene mutations was examined in 330 randomly selected patients treated with cochlear implantation.Results:Overall, 276 patients (83.64 per cent) carried variations in the GJB2 gene. Seventeen different genotypes were identified, including 10 confirmed pathogenic mutations (c.235delC, c.299delAT, c.176del16, p.E47X, p.T123N, p.V167M, p.C218Y, p.T86R, p.V63L and p.R184Q), 3 polymorphisms (p.V27I, p.E114 G and p.I203 T) and 2 unidentified mutations (p.V37I and c.571 T > C).Conclusion:A total of 103 patients (31.2 per cent) carried 2 confirmed pathogenic mutations. The frequency of c.235delC was higher than that reported previously in the Jiangsu province. The two novel mutations identified, 69C > G and 501G > A, are likely to be polymorphisms.

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Gene mutation analysis and genetic counseling for patients with non‑syndromic hearing loss in Linyi region

Experimental and Therapeutic Medicine ◽

10.3892/etm.2018.6927 ◽

2018 ◽

Author(s):

Huafeng Li ◽

Jigang Qiu ◽

Jinping Zhu ◽

Yuqiang Huang

Keyword(s):

Hearing Loss ◽

Genetic Counseling ◽

Gene Mutation ◽

Mutation Analysis ◽

Syndromic Hearing Loss ◽

Gene Mutation Analysis

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Whole-Genome Sequencing Improves the Diagnosis of DFNB1 Monoallelic Patients

Genes ◽

10.3390/genes12081267 ◽

2021 ◽

Vol 12 (8) ◽

pp. 1267

Author(s):

Anaïs Le Nabec ◽

Mégane Collobert ◽

Cédric Le Maréchal ◽

Rémi Marianowski ◽

Claude Férec ◽

...

Keyword(s):

Hearing Loss ◽

Whole Genome Sequencing ◽

Genome Sequencing ◽

Gjb2 Gene ◽

Whole Genome ◽

Genetic Origin ◽

Functional Assays ◽

Syndromic Hearing Loss ◽

Sensory Defect

Hearing loss is the most common sensory defect, due in most cases to a genetic origin. Variants in the GJB2 gene are responsible for up to 30% of non-syndromic hearing loss. Today, several deafness genotypes remain incomplete, confronting us with a diagnostic deadlock. In this study, whole-genome sequencing (WGS) was performed on 10 DFNB1 patients with incomplete genotypes. New variations on GJB2 were identified for four patients. Functional assays were realized to explore the function of one of them in the GJB2 promoter and confirm its impact on GJB2 expression. Thus, in this study WGS resolved patient genotypes, thus unlocking diagnosis. WGS afforded progress and bridged some gaps in our research.

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Mutations in the connexin26/GJB2 gene are the most common event in non-syndromic hearing loss among the German population

Human Mutation ◽

10.1002/humu.1138 ◽

2001 ◽

Vol 17 (6) ◽

pp. 521-522 ◽

Cited By ~ 59

Author(s):

Heinz Gabriel ◽

Petra Kupsch ◽

J�rgen Sudendey ◽

Elke Winterhager ◽

Klaus Jahnke ◽

...

Keyword(s):

Hearing Loss ◽

Gjb2 Gene ◽

German Population ◽

Common Event ◽

Syndromic Hearing Loss

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GPRASP2, a novel causative gene mutated in an X-linked recessive syndromic hearing loss

Journal of Medical Genetics ◽

10.1136/jmedgenet-2016-104320 ◽

2017 ◽

Vol 54 (6) ◽

pp. 426-430 ◽

Cited By ~ 3

Author(s):

Guangqian Xing ◽

Jun Yao ◽

Chunyu Liu ◽

Qinjun Wei ◽

Xuli Qian ◽

...

Keyword(s):

Hearing Loss ◽

Gene Mutation ◽

In Silico ◽

In Silico Analysis ◽

Chinese Family ◽

Causative Gene ◽

Genetic Hearing Loss ◽

Missense Variation ◽

Multiple Structures ◽

Syndromic Hearing Loss

BackgroundA substantial amount of nuclear genes have been identified to be implicated in genetic hearing loss, while X-linked hearing loss is genetically heterogeneous and relatively infrequent.ObjectiveTo identify the causative gene mutation in a five-generation Chinese family with an X-linked recessive syndromic hearing loss (SHL).MethodsTargeted X-chromosome exome sequencing was conducted, and cosegregation analysis was performed in the members of the affected family. The in silico and expression studies were also performed.ResultsA 2-bp missense mutation (c.1717_1718GC>AA, p.A573N) in the G protein-coupled receptor associated sorting protein 2 (GPRASP2) gene was identified in four hemizygous male patients and two heterozygous female carriers, which was cosegregated with the clinical phenotypes in this family. In silico analysis supported that this gene mutation is functionally deleterious, and it was detected that homologousGprasp2was highly expressed in multiple structures of the mouse cochlea, which suggested thatGPRASP2might be the genetic cause for the described disease phenotypes.ConclusionsThis study presented a novel X-linked SHL combined with unique and unrecognised clinical features, and a missense variation ofGPRASP2was first identified to be implicated in X-linked SHL.

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Investigating GJB2 Mutation in 31 Individuals With Non-syndromic Hearing Loss

Journal of Arak University of Medical Sciences ◽

10.32598/jams.24.1.4277.6 ◽

2021 ◽

Vol 24 (1) ◽

pp. 50-61

Author(s):

Pedram Pouryari Biyachal ◽

◽

Najmeh Ranji ◽

Ali Nazemi ◽

◽

...

Keyword(s):

Hearing Loss ◽

Cross Sectional Study ◽

Gjb2 Gene ◽

Common Mutation ◽

Cross Sectional ◽

Gjb2 Mutation ◽

Syndromic Hearing Loss ◽

Pcr Method ◽

Gilan Province ◽

35Delg Mutation

Background and Aim: Non-syndromic hearing loss is a genetically heterogeneous disorder. Mutation in the GJB2 gene is a major cause of non-syndromic hearing loss in numerous countries. This study aimed to evaluate GJB2 mutations in 31 individuals with non-syndromic hearing loss Methods & Materials: In this descriptive cross-sectional study, the required blood samples were collected from 31 individuals with non-syndromic hearing loss in Rasht and Bandar Anzali Cities, Gilan Province, Iran. After DNA isolation, the GJB2 gene was amplified by the PCR method and underwent sequencing. Ethical Considerations:This study was approved by the Ethics Committee of the Islamic Azad University, Mashhad Branch (Code: IR.IAU.MSHD.REC.1398.027). Results: In this study, 3 mutations were determined in 18 individuals with hearing loss. Accordingly, 35delG mutation had the highest frequency (48.38%) in individuals with hearing loss as homozygote (n=14) and heterozygote (n=2). A patient with heterozygosity in V153I mutation and a patient with compound heterozygosity in 35delG/G200R mutation was determined. Conclusion: It appears that 35delG mutation is a common mutation in the GJB2 gene in individuals with non-syndromic hearing loss in Guilan Province.

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Identification of Main Genetic Causes Responsible for Non-Syndromic Hearing Loss in a Peruvian Population

Genes ◽

10.3390/genes10080581 ◽

2019 ◽

Vol 10 (8) ◽

pp. 581 ◽

Cited By ~ 1

Author(s):

Figueroa-Ildefonso ◽

Bademci ◽

Rajabli ◽

Cornejo-Olivas ◽

Villanueva ◽

...

Keyword(s):

Hearing Loss ◽

Genetic Factors ◽

Stop Codon ◽

Premature Stop Codon ◽

Gjb2 Gene ◽

Pathogenic Variants ◽

Novel Variants ◽

Syndromic Hearing Loss ◽

Different Populations ◽

Global Population

: Hearing loss (HL) is a common sensory disorder affecting over 5% of the global population. The etiology underlying HL includes congenital and acquired causes; genetic factors are the main cause in over 50% of congenital cases. Pathogenic variants in the GJB2 gene are a major cause of congenital non-syndromic hearing loss (NSHL), while their distribution is highly heterogeneous in different populations. To the best of our knowledge, there is no data regarding the genetic etiologies of HL in Peru. In this study, we screened 133 Peruvian families with NSHL living in Lima. We sequenced both exons of the GJB2 gene for all probands. Seven probands with familial NSHL that remained negative for GJB2 variants underwent whole genome sequencing (WGS). We identified biallelic pathogenic variants in GJB2 in 43 probands; seven were heterozygous for only one allele. The c.427C>T variant was the most common pathogenic variant followed by the c.35delG variant. WGS revealed three novel variants in MYO15A in two probands, one of them was predicted to affect splicing and the others produce a premature stop codon. The Peruvian population showed a complex profile for genetic variants in the GJB2 gene, this particular profile might be a consequence of the admixture history in Peru.

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