scholarly journals GJB2: Frequency of the Less Common Variants in a Sample of the Portuguese Population

2021 ◽  
Vol 34 (13) ◽  
Author(s):  
Cláudia Sousa Reis ◽  
Ana Cristina Santos ◽  
Henrique Barros ◽  
Susana Fernandes ◽  
Carla Pinto Moura
Keyword(s):  
Hearing Loss ◽  
Caucasian Population ◽  
Hearing Impaired ◽  
Gjb2 Gene ◽  
Common Variants ◽  
Patient Assessment ◽  
Portuguese Population ◽  
Moderate Hearing Loss ◽  
Selection Of

Introduction: Sequence variants in the GJB2 gene account for up to 50% of cases of non-syndromic sensorineural hearing loss in the Caucasian population. In this study, we report the frequency of the less common variants of the GJB2 gene in a Portuguese sample and compare these frequencies with those of a group of hearing-impaired patients.Material and Methods: In order to select the less common GJB2 variants, 147 hearing-impaired patients followed in Centro Hospitalar Universitário de São João were evaluated. Afterwards, the presence of those variants was tested in 360 individuals from Generation 21.Results: The patient assessment enabled the selection of 11 GJB2 variants. Of those, 10 were investigated in Generation 21 participants, with only four being detected, in heterozygosity: p.Phe83Leu, p.Arg127His, p.Val153Ile and p.Asn206Ser, with the allelic frequencies (95% confidence interval) of 0.14% (0.01% - 0.87%), 0.28% (0.01% - 1.08%), 0.97% (0.43% - 2.04%) and 0.14% (0.01% - 0.88%), respectively. Two variants, p.Val37Ile and p.Val95Met, were more frequent in the patients’ group with statistical significance.Discussion: Our results allow for the p.Arg127His and p.Val153Ile variants to comply with polymorphism criteria and support the pathogenicity of p.Val37Ile and p.Val95Met variants. Moreover, two cases of moderate hearing loss were explained by the p.Val37Ile/p. Asn206Ser genotype, substantiating both the pathogenicity of such variants and the hypothesis that compound heterozygosity with p.Ans206Ser is associated with mild-moderate genotypes.Conclusion: Understanding the role of the variants is essential in order to provide genetic counselling to patients and their families. We explored a set of uncommon GJB2 variants that comprised 12% of the hearing-impaired patients in this study, supporting the relevance of their description.

scholarly journals GJB2 and GJB6 genes mutations in children with non-syndromic hearing loss

2017 ◽  
Vol 25 (1) ◽  
pp. 37-46 ◽  
Author(s):  
Călin Lazăr ◽  
Radu Popp ◽  
Camelia Al-Khzouz ◽  
Gheorghe Mihuț ◽  
Paula Grigorescu-Sido
Keyword(s):  
Hearing Loss ◽  
Gjb2 Gene ◽  
Pcr Analysis ◽  
Profound Hearing Loss ◽  
Prevalence Data ◽  
Sample Group ◽  
First Case ◽  
Syndromic Hearing Loss ◽  
The Moment ◽  
Moderate Hearing Loss

Abstract Introduction. At the moment there is not enough data in Romania about the incidence of the main genetic mutations which can cause hearing loss. Objective. The current research aims to determine on a representative sample the prevalence of two mutations of genes GJB2 -c.35delG and p.W24X- and two mutations of genes GJB6 -del(GJB6-D13S1830), del(GJB6-D13S1854) respectively - in patients with congenital nonsyndromic sensorineural hearing loss (CNSHL). Methods: The sample group included 179 children with CNSHL. The evaluation consist in: a.Clinical, laboratory and imagistic examination; b.ENT exam and audiological evaluation. c.Two methods (semi-nested PCR technique followed by RFLP, validated with ARMS-PCR analysis) for detection of c.35delG and pW24X mutations; d.PCR-multiplex technique for detecting del(GJB6-D13S1830) and del (GJB6-D13S1854). Results: The audiological diagnosis was: profound hearing loss in 116 patients (64.8%), severe hearing loss in 29 children (16.2%) and moderate hearing loss in 34 patients (representing 19% of the trial patients). The prevalence for the three mutations was: 27.3 % for c.35delG, 3.6 % for p.W24X and 0.28% for del(GJB6-D13S1830). The detection of the three mutations (two on GJB2 gene and one on GJB 6 gene) has allowed to establish the genetic cause for deafness in 45 patients, representing 25.14% of the sample group. Our study is reporting the first case in Romania with a mutation of gene GJB6. Mutation del(GJB6-D13S1854) lacked in all 179 patients. Conclusion: The prevalence data obtained in the current research are comparable to data communicated by studies from other European countries.

scholarly journals Role of Subtitles in L2 Acquisition and Comprehension: A Pilot Study of Hearing-Impaired Students

Languages ◽  
2021 ◽  
Vol 6 (1) ◽  
pp. 17
Author(s):  
Mila Vulchanova ◽  
Ingvild Kjølstad Lervåg
Keyword(s):  
Hearing Loss ◽  
Language Processing ◽  
Hard Of Hearing ◽  
First Language ◽  
L2 Acquisition ◽  
Advanced Learners ◽  
Mild Hearing Loss ◽  
Video Material ◽  
Moderate Hearing Loss

The purpose of this study was to investigate whether subtitles can facilitate language processing in English as a second language (L2) and, if so, which subtitles would be more beneficial for hard-of-hearing students with Norwegian as their first language. In total, 14 advanced learners of L2 English were recruited and tested on English comprehension and target vocabulary items based on video material provided with subtitles in English or Norwegian in comparison to no subtitles (control condition). Subtitles aided comprehension of the plot, tested immediately after clip presentation, with an advantage for English subtitles over Norwegian subtitles and no subtitles. Furthermore, subtitles were found to enhance the performance of the participants with moderate hearing loss more than they did for mild hearing loss participants. The inclusion of English subtitles only marginally enhanced vocabulary understanding for both mild and moderate hearing loss students. The findings of this study can be transferred to classrooms and may supplement other methods of adjusting the academic environment, in order to meet the need of students with hearing loss.

scholarly journals The Functional Role of CONNEXIN 26 Mutation in Nonsyndromic Hearing Loss, Demonstrated by Zebrafish Connexin 30.3 Homologue Model

Cells ◽  
2020 ◽  
Vol 9 (5) ◽  
pp. 1291
Author(s):  
Hsuan-An Su ◽  
Ting-Wei Lai ◽  
Shuan-Yow Li ◽  
Tzu-Rong Su ◽  
Jiann-Jou Yang ◽  
...  
Keyword(s):  
Hearing Loss ◽  
Structural Changes ◽  
Dominant Negative ◽  
Gjb2 Gene ◽  
Dominant Negative Effect ◽  
Connexin 26 ◽  
Transgenic Zebrafish ◽  
Nonsyndromic Hearing Loss ◽  
Transgenic Lines

Nonsyndromic hearing loss (NSHL) is of great clinical importance, and mutations in the GJB2 gene and the encoded human CONNEXIN 26 (CX26) protein play important roles in the genetic pathogenesis. The CX26 p.R184Q mutation was shown to be a dominant-negative effect in our previous study. Previously, we also demonstrated that zebrafish Cx30.3 is orthologous to human CX26. In the present study, we established transgenic zebrafish models with mutated Cx30.3 specifically expressed in the supporting cells of zebrafish inner ears driven by the agr2 promoter, to demonstrate and understand the mechanism by which the human CX26 R.184 mutation causes NSHL. Our results indicated that significant structural changes in the inner ears of transgenic lines with mutations were measured and compared to wild-type zebrafish. Simultaneously, significant alterations of transgenic lines with mutations in swimming behavior were analyzed with the zebrafish behavioral assay. This is the first study to investigate the functional results of the CX26 p.R184Q mutation with in vivo disease models. Our work supports and confirms the pathogenic role of the CX26 p.R184Q mutation in NSHL, with a hypothesized mechanism of altered interaction among amino acids in the connexins.

Screening of 10 DFNB Loci Causing Autosomal Recessive Non-Syndromic Hearing Loss in Two Iranian Populations Negative for GJB2 Mutations

2020 ◽  
Author(s):  
Mahbobeh KOOHIYAN ◽  
Somayeh REIISI ◽  
Fatemeh AZADEGAN-DEHKORDI ◽  
Mansoor SALEHI ◽  
Hamidreza ABTAHI ◽  
...  
Keyword(s):  
Hearing Loss ◽  
Autosomal Recessive ◽  
Homozygosity Mapping ◽  
Gjb2 Gene ◽  
Global Public Health ◽  
Relative Contribution ◽  
Syndromic Hearing Loss ◽  
High Degree ◽  
Gjb2 Mutations

Background: Autosomal recessive non-syndromic hearing loss (ARNSHL), one of the global public health concerns, is marked by a high degree of genetic heterogeneity. The role of GJB2, as the most common cause of ARNSHL, is only <20% in the Iranian population. Here, we aimed to determine the relative contribution of several apparently most common loci in a cohort of ARNSHL Iranian families that were negative for the GJB2 mutations. Methods: Totally, 80 Iranian ARNSHL families with 3 or more affected individuals from Isfahan and Hamedan provinces, Iran were enrolled in 2017. After excluding mutations in the GJB2 gene via Sanger sequencing, 60 negative samples (30 families from each province) were analyzed using homozygosity mapping for 10 ARNSHL loci. Results: Fourteen families were found to be linked to five different known loci, including DFNB4 (5 families), DFNB2 (3 families), DFNB7/11 (1 family), DFNB9 (2 families) and DFNB3 (3 families). Conclusion: Despite the high heterogeneity of ARNSHL, the genetic causes were determined in 23.5% of the studied families using homozygosity mapping. This data gives an overview of the ARNSHL etiology in the center and west of Iran, used to establish a diagnostic gene panel including most common loci for hearing loss diagnostics.

Older Adult Performance on the Communication Profile for the Hearing Impaired

1999 ◽  
Vol 42 (4) ◽  
pp. 785-796 ◽  
Author(s):  
Dean C. Garstecki ◽  
Susan F. Erler
Keyword(s):  
Hearing Loss ◽  
Hearing Impaired ◽  
Self Assessment ◽  
Adult Performance ◽  
Age Related ◽  
Problem Awareness ◽  
Age Related Hearing Loss ◽  
Older Men And Women ◽  
Gender Specific ◽  
Moderate Hearing Loss

Gender difference in auditory function with age is well documented. However, little is known about the influence of interacting sensory, psycho-social, and economic variables on adjustment to hearing loss. Adjustment to acquired, mild-to-moderate hearing loss by advantaged older women and men was examined using the Communication Profile for the Hearing Impaired (CPHI) (Demorest & Erdman, 1987). Correlational analyses revealed relationships between scales to be similar for women and men. Controlling for socio-demographic and hearing variables, group responses for the majority of CPHI scales did not differ significantly. Six scales differed significantly, and those results are discussed. When compared to men, women assigned greater importance to effective social communication, were more likely to use nonverbal communication strategies, reported greater anger and stress, and reported greater problem awareness and less denial associated with hearing loss. The CPHI is a useful tool for specifying parameters of perceived communication handicap for both older men and women. Findings underscore the need to consider gender-specific self-assessment of communication and personal adjustment in clinical management of older adults with age-related hearing loss.

scholarly journals Role of DFNB1 mutations in hereditary hearing loss among assortative mating hearing impaired families from South India

2018 ◽  
Vol 19 (1) ◽  
Author(s):  
Pavithra Amritkumar ◽  
Justin Margret Jeffrey ◽  
Jayasankaran Chandru ◽  
Paridhy Vanniya S ◽  
M. Kalaimathi ◽  
...  
Keyword(s):  
Hearing Loss ◽  
Assortative Mating ◽  
South India ◽  
Hearing Impaired ◽  
Hereditary Hearing Loss

Intelligibility of Telephone Speech for the Hearing Impaired When Various Microphones Are Used for Acoustic Coupling

1991 ◽  
Vol 34 (1) ◽  
pp. 183-188 ◽  
Author(s):  
Claus P. Janota ◽  
Jeanette Olach Janota
Keyword(s):  
Hearing Loss ◽  
Pressure Gradient ◽  
Hearing Aids ◽  
Hearing Impaired ◽  
Acoustic Coupling ◽  
Telephone Speech ◽  
Moderate Hearing Loss

This study set out to systematically measure the effect of using various candidate microphones for acoustic coupling of hearing aids to a telephone receiver. Intelligibility of words was determined for three microphones and three levels of interfering noise for a total of nine conditions. The subjects all had moderate hearing loss. It was found that microphones that exhibit pressure gradient sensitivity can, when properly positioned relative to the telephone receiver, increase intelligibility scores significantly. Results show that comparable listening performance is achieved with a pressure gradient microphone at a 10 dB higher level of interfering noise than with a microphone that is only sensitive to pressure. The results quantify the effect of microphones in acoustic coupling of hearing aids to telephones and point to a possible means for improving some types of hearing aids to facilitate telephone use for the hearing-impaired.

scholarly journals The Role of Spectral Resolution, Working Memory, and Audibility in Explaining Variance in Susceptibility to Temporal Envelope Distortion

2014 ◽  
Vol 25 (06) ◽  
pp. 592-604 ◽  
Author(s):  
Evelyn Davies-Venn ◽  
Pamela Souza
Keyword(s):  
Working Memory ◽  
Hearing Loss ◽  
Speech Recognition ◽  
Spectral Resolution ◽  
Hearing Aid ◽  
Severe Hearing Loss ◽  
Temporal Envelope ◽  
Repeated Measures Design ◽  
Moderate Hearing Loss

Background: Several studies have shown that hearing thresholds alone cannot adequately predict listeners’ success with hearing-aid amplification. Furthermore, previous studies have shown marked differences in listeners’ susceptibility to distortions introduced by certain nonlinear amplification parameters. Purpose: The purpose of this study was to examine the role of spectral resolution, working memory, and audibility in explaining perceptual susceptibility to temporal envelope and other hearing-aid compression-induced distortions for listeners with mild to moderate and moderate to severe hearing loss. Research Design: A between-subjects repeated-measures design was used to compare speech recognition scores with linear versus compression amplification, for listeners with mild to moderate and moderate to severe hearing loss. Study Sample: The study included 15 adult listeners with mild to moderate hearing loss and 13 adults with moderate to severe hearing loss. Data Collection/Analysis: Speech recognition scores were measured for vowel-consonant-vowel syllables processed with linear, moderate compression, and extreme compression amplification. Perceptual susceptibility to compression-induced temporal envelope distortion was defined as the difference in scores between linear and compression amplification. Both overall scores and consonant feature scores (i.e., place, manner, and voicing) were analyzed. Narrowband spectral resolution was measured using individual measures of auditory filter bandwidth at 2000 Hz. Working memory was measured using the reading span test. Signal audibility was quantified using the Aided Audibility Index. Multiple linear regression was used to determine the predictive role of spectral resolution, working memory, and audibility benefit on listeners’ susceptibility to compression-induced distortions. Results: For all listeners, spectral resolution, working memory, and audibility benefit were significant predictors of overall distortion scores. For listeners with moderate to severe hearing loss, spectral resolution and audibility benefit predicted distortion scores for consonant place and manner of articulation features, and audibility benefit predicted distortion scores for consonant voicing features. For listeners with mild to moderate hearing loss, the model did not predict distortion scores for overall or consonant feature scores. Conclusions: The results from this study suggest that when audibility is adequately controlled, measures of spectral resolution may identify the listeners who are most susceptible to compression-induced distortions. Working memory appears to modulate the negative effect of these distortions for listeners with moderate to severe hearing loss.

Teacher Identification of Elementary School Children with Hearing Loss

1978 ◽  
Vol 9 (1) ◽  
pp. 24-28 ◽  
Author(s):  
Richard H. Nodar
Keyword(s):  
Elementary School ◽  
Hearing Loss ◽  
School Children ◽  
Elementary School Children ◽  
Total Sample ◽  
Hearing Impaired ◽  
Teacher Interviews ◽  
Teacher Screening ◽  
Children With Hearing Loss ◽  
Hearing Problems

The teachers of 2231 elementary school children were asked to identify those with known or suspected hearing problems. Following screening, the data were compared. Teachers identified 5% of the children as hearing-impaired, while screening identified only 3%. There was agreement between the two procedures on 1%. Subsequent to the teacher interviews, rescreening and tympanometry were conducted. These procedures indicated that teacher screening and tympanometry were in agreement on 2% of the total sample or 50% of the hearing-loss group. It was concluded that teachers could supplement audiometry, particularly when otoscopy and typanometry are not available.

Sign in / Sign up

Export Citation Format

Share Document