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

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.

scholarly journals Spectrum and Frequency of the GJB2 Gene Mutations Among Latvian Patients with Prelingual Nonsyndromic Hearing Loss

2009 ◽  
Vol 63 (4-5) ◽  
pp. 198-203
Author(s):  
Olga Šterna ◽  
Natālija Proņina ◽  
Ieva Grīnfelde ◽  
Sandra Kušķe ◽  
Astrīda Krūmiņa ◽  
...  
Keyword(s):  
Hearing Loss ◽  
Gene Mutations ◽  
Gjb2 Gene ◽  
Connexin 26 ◽  
Compound Heterozygous ◽  
Nonsyndromic Hearing Loss ◽  
Profound Hearing Loss ◽  
Common Cause ◽  
Gjb2 Mutation ◽  
35Delg Mutation

Spectrum and Frequency of the GJB2 Gene Mutations Among Latvian Patients with Prelingual Nonsyndromic Hearing Loss Mutations in the GJB2 gene (connexin 26) are the most common cause of congenital nonsyndromic severe-to-profound hearing loss. Sixty-five hearing impaired probands from Latvia were tested for mutations in the GJB2 gene to determine the percentage of hearing loss attributed to connexin 26 and the types of mutations in this population. A total of 62% of patients tested had GJB2 mutations. Four different mutations in the GJB2 gene were identified in Latvian patients with nonsyndromic sensorineural hearing loss: 35delG, 311-324del14, 235delC and M34T. The most prevalent mutation is 35delG (47% of all probands were homozygous and 8% compound heterozygous). Our findings support the conclusion that the 35delG mutation is the most prevalent GJB2 mutation and that it is the common cause of hereditary nonsyndromic hearing loss in populations of European descent.

Hearing loss associated with 35delG mutation in Connexin-26 (GJB2) gene: audiogram analysis

2004 ◽  
Vol 118 (1) ◽  
pp. 8-11 ◽  
Author(s):  
Fabrizio Salvinelli ◽  
Manuele Casale ◽  
Luca D’Ascanio ◽  
Luca Firrisi ◽  
Fabio Greco ◽  
...  
Keyword(s):  
Hearing Loss ◽  
Autosomal Recessive ◽  
Pure Tone Audiometry ◽  
Gjb2 Gene ◽  
Connexin 26 ◽  
Common Mutation ◽  
Congenital Hearing Loss ◽  
35Delg Mutation ◽  
The Relationship

35delG is the most common mutation in the Connexin-26 gene, representing a major cause of autosomal recessive hearing loss. The aim of this study was to evaluate the relationship between the audiological phenotype and the 35delG mutation in 64 Sicilians with non-syndromic deafness. Pure-tone audiometry and a screening for 35delG mutation were performed. Audiograms were evaluated according to the classification of Liu and Xu. Thirteen homozygotes and nine heterozygotes for the investigated mutation were found. Symmetrical hearing loss was significantly (p=0.008) more common in homozygous subjects than in those without the Connexin-26 mutation. Profound-severe hypoacusia was found in 92.3 per cent of 35delG homozygous, 22.3 per cent of heterozygous and 58.7 per cent of 35delG absent patients. Residual shape audiograms were more frequent in homozygotes. A molecular analysis for the 35delG mutation should be performed in cases of symmetric, severe-profound congenital hearing loss, as a genetic cause is probable in such cases.

High frequency of heterozygosity in GJB2 mutations among patients with non-syndromic hearing loss

2008 ◽  
Vol 123 (3) ◽  
pp. 273-277 ◽  
Author(s):  
G Khandelwal ◽  
S Bhalla ◽  
M Khullar ◽  
N K Panda
Keyword(s):  
Hearing Loss ◽  
Indian Population ◽  
Gjb2 Gene ◽  
Coding Region ◽  
Syndromic Hearing Loss ◽  
Polymerase Chain ◽  
35Delg Mutation ◽  
Control Study ◽  
Gjb2 Mutations ◽  
Prevalent Mutation

AbstractObjective:To determine the prevalence of GJB2 mutations among subjects with congenital, non-syndromic, sensorineural hearing loss, within a north Indian population.Materials and methods:This was a case–control study in which the frequencies of the three most prevalent GJB2 mutations (35delG, W24X and 167delT) were studied. Polymerase chain reaction restriction fragment length polymorphism assays were performed to detect these mutations. The entire coding region of the GJB2 gene was sequenced in all patients, and also in any of their family members who showed GJB2 mutations.Results:The 35delG mutation was found to be the most prevalent mutation (21 per cent), followed by the W24X mutation (7 per cent). This is the first report of the 35delG mutation in an Indian population. One patient was a compound heterozygote for 35delG/W24X. The 167delT mutation was not observed in any patient.Conclusions:These findings challenge the classical view that the W24X variant of the GJB2 gene represents a single ‘founder’ mutation.

Hearing Outcome of Stapes Surgery in NIENT, Bangladesh

2020 ◽  
Vol 26 (1) ◽  
pp. 31-36
Author(s):  
Md Zakaria Sarkar ◽  
AHM Ferdows Nur ◽  
Utpal Kumar Dutta ◽  
Muhammad Rafiqul Islam ◽  
Debabrota Roy ◽  
...  
Keyword(s):  
Hearing Loss ◽  
Cross Sectional Study ◽  
Surgical Trauma ◽  
Group 14 ◽  
Progressive Hearing Loss ◽  
Cross Sectional ◽  
Hearing Gain ◽  
Hearing Outcome

Objective: The aim of this study was to evaluate hearing outcome after stapedotomy in patients with Otosclerosis. Methods: This cross sectional study was carried out from July 2017 to January 2019 in National Institute of ENT, Unit V. About 22 patients with Otosclerosis were included in this study. Diagnosis of Otosclerosis was based on the history, medical status with Otoscopy, Tuning fork tests and Audiometric tests. We compiled data on the pre and post operative air-bone gap (ABG) at 0.5, 1, 2 KHZ. The ABG was Calculated using AC and BC thresholds on the same audiogram. Post operative hearing gain was then Calculated from the ABG before the operation minus the ABG of the last follow up examination Results: In this study most of the cases were age group 14-30 years (72.7%), female (54.5%). Most common symptoms was progressive hearing loss, tinnitus (77.8%).The average preoperative hearing loss in this study was (AC) was 48.31±7.68. The average post opt. hearing (AC) at follow up was 28.95±10.30 with an average hearing gain of 15.40±8.53 dB which was significant. The average pre-operative ABG was 28.99 dB ± 8.10. The average post opt. ABG was analyzed at 1 follow up showed ABG 13.18±8.09 dB which was found to be significant. Conclusion: Stapedotomy is an effective surgical procedure for the treatment of otosclerosis which leads to improvement in patient’s quality of life. A favorable hearing outcome can be obtained by the combination of experienced hands with minimal surgical trauma and appropriate surgical technique. Bangladesh J Otorhinolaryngol; April 2020; 26(1): 31-36

Detection of Streptococcus pneumoniae in Sputum Samples by Real- Time PCR.

2020 ◽  
Vol 18 ◽  
Author(s):  
Pegah Shakib ◽  
Mohammad Reza Zolfaghari
Keyword(s):  
Streptococcus Pneumoniae ◽  
Real Time ◽  
Real Time Pcr ◽  
False Negative ◽  
Cross Sectional Study ◽  
Laboratory Culture ◽  
Cross Sectional ◽  
Negative Results ◽  
False Negative Results ◽  
Pcr Method

Background: Conventional laboratory culture-based methods for diagnosis of Streptococcus pneumoniae are time-consuming and yield false negative results. Molecular methods including real-time (RT)-PCR rapid methods and conventional PCR due to higher sensitivity and accuracy have been replaced instead traditional culture assay. The aim of the current study was to evaluate lytA gene for detection of Streptococcus pneumoniae in the cerebrospinal fluid of human patients with meningitis using real-time PCR assay. Material and Methods: In this cross-sectional study, a total of 30 clinical specimens were collected from patients in a period from September to December 2018. In order to evaluate the presence of lytA gene, conventional and real-time PCR methods were used without culture. Results: From 30 sputum samples five (16.66%) isolates were identified as S. pneumoniae by lytA PCR and sequencing. Discussion: In this research, an accurate and rapid real-time PCR method was used, which is based on lytA gene for diagnosis of bacteria so that it can be diagnosed. Based on the sequencing results, the sensitivity for detection of lytA gene was 100% (5/5).

scholarly journals Hearing Loss as a Function of Aging and Diabetes Mellitus: A Cross Sectional Study

PLoS ONE ◽  
2014 ◽  
Vol 9 (12) ◽  
pp. e116161 ◽  
Author(s):  
In-Hwan Oh ◽  
Jong Hoon Lee ◽  
Dong Choon Park ◽  
MyungGu Kim ◽  
Ji Hyun Chung ◽  
...  
Keyword(s):  
Diabetes Mellitus ◽  
Hearing Loss ◽  
Cross Sectional Study ◽  
Sectional Study ◽  
Cross Sectional

A study on the proportion of hearing impairment among percussionists in Thrissur district of Kerala

2021 ◽  
Vol 9 (3) ◽  
pp. 816
Author(s):  
Jubina Bency A. T. ◽  
Sarangi . ◽  
Sebastian Roy ◽  
Shalu Sara Mathew ◽  
Shamseena A. ◽  
...  
Keyword(s):  
Hearing Loss ◽  
Hearing Impairment ◽  
Work Experience ◽  
Health Care Services ◽  
Cross Sectional Study ◽  
Moderate Degree ◽  
Cross Sectional ◽  
Hearing Ability ◽  
Care Services ◽  
Mild Degree

Background: Hearing loss is a cause of global concern. Percussionists are exposed to greater levels of continuous or intermittent noise than others. Little is known about the relationship between percussion activity and hearing impairment. The early detection of the same and subsequent management makes a significant reduction in the burden of health care services. The objective was to study the proportion of hearing impairment in percussionists in the district of Thrissur using an IOS based mobile application.Methods: A cross sectional study was done on percussionists from Thrissur district who has experience of more than five years and has no congenital or traumatic hearing loss. A predesigned semi structured questionnaire was given and hearing tests were done using a mobile application U hear in a sound proof setting to understand the current state of hearing ability amoung the percussionists.Results: A total of 39 subjects were involved in our study of which all were males. Mean age of our study population was 30.44+12.04. most of them were diagnosed with at least mild degree of hearing loss of one of the ear or both the ears. 15.4% of them had mild degree of hearing loss, 64.1% had moderate degree of hearing loss and 20.5% had severe hearing loss.Conclusions: The study shows percussionists are more exposed to sounds of various frequencies for longer duration, they are more prone to hearing loss. The study brought out that age is directly proportional to hearing loss, music induced hearing loss progress at a rate proportion to the work experience. 

The effects of dyslipidemia on noise-induced hearing loss in a petrochemical workers in the Southwest of Iran

Work ◽  
2021 ◽  
pp. 1-8
Author(s):  
Payam Rashnoudi ◽  
Arman Amiri ◽  
Maryam Omidi ◽  
Abbas Mohammadi
Keyword(s):  
Hearing Loss ◽  
Cross Sectional Study ◽  
Blood Cholesterol ◽  
Noise Induced Hearing Loss ◽  
Total Blood ◽  
Cross Sectional ◽  
Inner Diameter ◽  
Spss Software ◽  
Southwest Of Iran ◽  
Total Blood Cholesterol

BACKGROUND: Research has shown that the decrease in the inner diameter of vessels caused by hyperlipidemia lowers the capacity for blood oxygen delivery to the cochlea. This leads to impaired cochlear metabolism and causes hearing problems. OBJECTIVE: The effects of dyslipidemia on noise-induced hearing loss in workers were examined. METHODS: This descriptive cross-sectional study was performed on 692 male employees in a petrochemical industry in the southwest of Iran exposed to 85 dB noise. Clinical audiometry and blood sample tests were used to evaluate the hearing and prevalence indices of dyslipidemia (cholesterol, triglyceride, HDL and LDL). The data were analyzed using SPSS software version 25 (p = 0.05). RESULTS: The results showed that the prevalence of dyslipidemia was 24.5%with abnormal relative triglyceride frequency of 49.5%, HDL of 28%, LDL of 33%, and total blood cholesterol level of 37.8%. There was no significant relationship between NIHL and dyslipidemia (p >  0.09). However, the major NIHL drops at different frequencies were in the individuals with dyslipidemia. The parameters age and dyslipidemia increased NIHL odds ratio (95%C.I.). by 1.130 (1.160–1.100) and 1.618 (2.418–1.082) respectively CONCLUSION: The rate of hearing loss in individuals with dyslipidemia increases at different frequencies and it leads to an increase of the OR of NIHL in individuals with dyslipidemia. We can control dyslipidemia and its effective factors. The NIHL is more common in people exposed to noise.

scholarly journals Comparison of sensorineural hearing loss characteristics in different hemodialysis vascular accesses

2020 ◽  
Author(s):  
Behieh Kohansall ◽  
Nasser Saeedi ◽  
Moeinoddin Hossein Beigi ◽  
Azam Moslemi ◽  
Akram Valizadeh
Keyword(s):  
Hearing Loss ◽  
Sensorineural Hearing Loss ◽  
Vascular Access ◽  
Demographic Data ◽  
Life Quality ◽  
Cross Sectional Study ◽  
Sensorineural Hearing ◽  
Moderate Degree ◽  
Cross Sectional ◽  
Significant Difference

Background and Aim: Sensorineural hearing loss (SNHL) is one of the complications in hemodialysis patients. Vascular access (VA) represents a lifeline for these patients affecting their life quality and clinical outcomes. Arterio­venous fistula is the gold standard of VAs with minor complications and better hemodialysis adequacy. There is no study investigating hearing differences in hemodialysis VAs. Hence, this study aimed to compare SNHL characteristics amongst hemodialysis VAs. Methods: This cross-sectional study conducted on 64 patients aged 18−60 years received regular hemodialysis in 2019. Demographic data and comorbid conditions were recorded based on patients’ case records and electronic databases. After a physical examination, otoscopy, tympa­nometry, and conventional audiometry, patients were divided into fistula (n = 26), permanent catheter (n = 36), and temporary catheter (n = 2) groups according to vascular access type. Results: Prevalence rate of SNHL was 63.89%, 50% and 50% in the permanent catheter, fistula and temporary catheter groups, respectively. Most patients had mild sloping-SNHL in the per­manent catheter and fistula groups as against moderate degree in the other group. There was no significant difference in hearing thresholds, deg­ree and audiogram shape among VA groups. No significant relation was found between age, sex, hemodialysis duration and disease duration with hearing loss in all groups (p > 0.05). Conclusion: More patients had SNHL in per­manent catheter group. Vascular access types, longer duration of hemodialysis and disease dur­ation do not seem to be associated with SNHL. However, further investigation is needed to cla­rify the relationship. Keywords: Sensorineural hearing loss; vascular access; chronic renal failure; hemodialysis

scholarly journals Whole-Genome Sequencing Improves the Diagnosis of DFNB1 Monoallelic Patients

Genes ◽  
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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