Validity and Reliability of the Turkish Version of the Glottal Function Index.

OBJECTIVES: A comprehensive evaluation is necessary for voice-related complaints, as it can benefit both the patient and physician in busy clinical settings. This study aimed to examine the Turkish adaptation of the Glottal Function Index (GFI-T), which can be quickly administered. STUDY DESIGNS: Phase 1 methodological, phase 2 prospective cohort. METHODS: This study was conducted in two phases. Firstly, the GFI was translated into Turkish, and its content validity was examined. The GFI-T was administered to 40 participants with voice disorders (M=41.3, SD=10) in the study group and 40 participants without voice disorders (M=37.5, SD=11.3) in the control group. Then GFI-T was readministered 2weeks later. The collected data were used for structural and convergent validity [correlation with Turkish version of the Voice Handicap Index-10 (VHI-10)], internal consistency, and test-retest reliability analyses. Secondly, 24 participants with vocal nodules were recruited separately from the first phase and were randomly divided into three groups. The first group underwent lax-vox therapy+vocal hygiene, the second group underwent resonance therapy+vocal hygiene, and the third group was provided only with vocal hygiene recommendations. The discriminative ability and construct validity of the GFI-T were examined by comparing pre- and post-assessments. RESULTS: The results indicated that the content validity indexes were 0.98 in the experts and 0.99 in the participants. Confirmatory factor analysis of the scale confirmed that a single-factor structure and goodness-of-fit indices were suitable. The GFI-T correlated 0.92 with the Turkish version of the VHI-10. The internal consistency was 0.96, and the test-retest value was 0.99. Significant differences (P < 0.001) and correlations with the Turkish version of VHI-10 were found in intragroup comparisons. CONCLUSIONS: The GFI-T is a reliable and valid tool for the self-assessment of voice disorders. The adaptation of this study to the pediatric population is recommended.

The effect of having a child with hearing impairment on parents.

OBJECTIVE: In this study, it was aimed to compare parents of children with hearing impairment (with cochlear implant (CI) or hearing aid) and parents of children with normal hearing (NH) in terms of care burden, self-efficacy and psychological resilience levels. METHODS: The study participants were parents of children aged 3-12 years. Zarit Care Burden Scale (ZCBS), Parental Self-Efficacy Scale (PSES) and Brief Psychological Resilience Scale (BPRS) were administered to the parents. RESULTS: The mean BPRS score was statistically significantly higher for the NH group than for the hearing impairment groups. It was found that the mean ZCBS score was statistically significantly higher for CI group than for the other groups (p < 0.05). A statistically significant and positive correlation was found between the PSES and BPRS scores of the CI group. CONCLUSION: It is thought that the results of this study will contribute to the creation of case-specific intervention/rehabilitation programs.

Validity and reliability of the ERSA questionnaire in Turkish.

This methodological study aimed to assess the validity and reliability of the Turkish version of the Evaluation of the Impact of Hearing Loss in Adults (ERSA) questionnaire for individuals with treated hearing loss. The study involved 200 participants, and both exploratory factor analysis and confirmatory factor analysis were used to examine structural validity. External validity was assessed by correlating ERSA scores with the Abbreviated Profile of Hearing Aid Benefit (APHAB). Internal consistency and test-retest reliability were evaluated using Cronbach's alpha and the intraclass correlation coefficient, respectively. The Turkish ERSA demonstrated strong psychometric properties, with significant correlations between APHAB and ERSA scores and excellent internal consistency and test-retest reliability. The findings suggest that the Turkish ERSA is a valid and reliable tool for evaluating the impact of hearing loss in individuals.

Does Chronic Subjective Tinnitus Affect Cognitive Performance in Normal Hearing Adults?

BACKGROUND: In literature, the cognitive performance results of normal hearing individuals with tinnitus are inconsistent. It also differs in the control of other factors that may affect cognition. PURPOSE: This study aimed to determine the differences in attention and memory performance between normal-hearing individuals with chronic subjective tinnitus and age-sex-education-matched healthy controls. STUDY SAMPLE: Normal-hearing individuals with subjective chronic tinnitus between 18-55 years of age, who have normal cognitive abilities [tinnitus group, n=30] and age-sex matched normal hearing individuals without tinnitus who have normal cognitive abilities [control group, n=30] were included in this study. DATA COLLECTION: The Montreal Cognitive Assessment Test (MoCA-TR) measured participants' general cognitive screening, and depressive symptoms were measured by Beck Depression Inventory (BDI). Tinnitus Handicap Inventory (THI) was used to determine the tinnitus handicap levels. Attention performance was evaluated with Stroop Test-TBAG Form, and short-term and working memory performances were evaluated with the Wechsler Adult Intelligence Scale-Revised (WAIS-R)-Digit Span Test. RESULTS: The tinnitus and control groups' depressive symptom scores were similar concerning the BDI (p=0.90). There was no statistically significant difference between both groups according to the completion time of the five sections of the Stroop Test, the number of errors and corrections of the Stroop 5 test, and the (WAIS-R)-Digit Span Test scores (p>0.05). CONCLUSIONS: In our study, the Stroop Test and Digit Span Test performances of individuals with tinnitus and normal hearing were similar to the control group. Despite previous studies claiming an effect of tinnitus on cognition, our contrary findings are discussed in the light of other demographic, audiological, and psychological measurement variables, especially hearing loss.

Processes of Emotion Idioms Comprehension of Turkish-Speaking People with Wernice's Aphasia.

INTRODUCTION: Idioms are commonly used in everyday language to convey emotions figuratively. The ability to comprehend and use idioms that incorporate emotional elements is crucial for effective communication in daily life, particularly among people with aphasia (PwA). Despite the interest in understanding the process of emotion idiom comprehension in PwA, limited information is available in the literature. Therefore, this study aimed to investigate the process of emotion idiom comprehension in people with Wernice's aphasia (PwWA) and compare it with that of neurotypical individuals. METHODS: Sixty idioms were selected based on their syntactic and semantic features, and participants evaluated their imageability. Sixteen idioms were chosen for the study and two types of tasks were prepared: written idiom-picture matching and written idiom-written text matching. These tasks were administered to two groups: 11 PwWA and 11 neurotypical individuals. The results were analysed in terms of task performance, response type, syntactic and semantic features, and emotional content. RESULTS: The emotion idiom comprehension scores of PwWA group were significantly lower than those of the neurotypical participants. PwWA had greater difficulty with the written idiom-picture matching task and tended to rely on the literal meanings of the idioms. There were differences in the semantic features between the two groups. Among the emotional idioms, PwWA showed significant differences in the types of emotions they were able to comprehend. CONCLUSIONS: The findings of this study suggest that regardless of the syntactic content of idioms, PwWA's ability to comprehend emotion idioms is impaired, and they tend to interpret them more literally. This study provides a useful method for assessing emotional idiom comprehension in PwA.

The Effect of Repositioning Maneuver Applied with the TRV Chair on Residual Dizziness after Benign Paroxysmal Positional Vertigo.

OBJECTIVE: This study aims to investigate the effect of TRV chair on residual dizziness (RD) after idiopathic posterior semicircular canal benign paroxysmal positional vertigo (BPPV) successfully treated with canalith repositioning maneuver (CRM). STUDY DESIGN: Prospective case-control study. SETTING: Hospital. PATIENTS: Thirty-three patients with posterior canal BPPV were included in the study. These patients were divided into two identical groups. CRM was applied to the first group with a TRV chair (TRV group) and manually to the second group (manual group). INTERVENTIONS: Dizziness Handicap Inventory (DHI), Beck Anxiety Inventory (BAI), and video head impulse test were applied to the patients. Patients in both groups were asked to report the RD developed after successful CRM daily by visual analog scale (VAS). RESULTS: The TRV group's first-day RD rate was 94.1% with VAS, and the RD duration was 2.47 ± 1.77 (0-7) days. The manual group's first-day RD rate was 100%, and the RD duration was 3.38 ± 1.70 (1-7) days. There was no difference between the groups in terms of RD duration ( p > 0.05). Mean RD severity and severity in the first 3 days were lower in the TRV group compared with the manual group ( p < 0.05). There was no difference between the groups on other days ( p > 0.05). In addition, there was a positive correlation between RD and DHI and BPPV duration ( p < 0.05). CONCLUSION: RD is a multifactorial symptom associated with how the repositioning maneuver is performed, BPPV duration, and DHI. Performing the repositioning maneuver with the TRV chair can reduce the severity of RD.

The effects of dietary and physical activity interventions on tinnitus symptoms: An RCT.

OBJECTIVE: Subjective tinnitus is defined as the perception of irregular sound at different frequencies. Although the underlying cause of tinnitus is unclear, increased body weight is known to increase tinnitus symptoms. The present study aimed to determine the effects of dietary and physical activity interventions on tinnitus symptoms. METHODS: Sixty-three obese subjects with tinnitus aged 20 to 65 years were divided into diet + physical activity (P.A.) (n = 15), diet (n = 16), P.A. (n = 15), and control (n = 17) groups. Dietary records, anthropometric measurements, Tinnitus Handicap Inventory (THI), Beck Depression Inventory (BDI), Short-Form Health Survey (SF-36), and Visual Analogue Scale (VAS) of all individuals were recorded and compared at the baseline and at study completion. RESULTS: Body weight decreased in the diet + P.A. (-5.9 (3.5) kg), diet (-3.4 (0.9) kg), and P.A. (-2.0 (2.1) kg) groups compared to the baseline (p < 0.05). There was a more significant decrease in tinnitus frequency, tinnitus severity, and VAS scores in individuals with a weight loss of ≥ 5.0% than in those with < 5.0% (p < 0.05). A decrease of 1 kg/m2 in BMI decreased the BDI score by 0.485 units and the THI score by 0.523 units. Step counts were increased in the diet + P.A. (3562.3±739.9) and P.A. (3797.1 ± 1801.1) groups compared to baseline (p < 0.01). Each increase of 1000 steps increased the SF-36 score by 1.592 units and decreased the THI score by 0.750 units (p < 0.05). CONCLUSION: Dietary and physical activity interventions, alone or in combination, alleviated tinnitus symptoms and increased quality of life in individuals with tinnitus. Due to its contribution to obesity prevention and positive effects on tinnitus, organizing dietary and physical activity programs for obese individuals with tinnitus would improve these individuals' quality of life.

Outcomes of Treatment of Multicanal Benign Paroxysmal Positional Vertigo by Means of TRV Chair.

INTRODUCTION: Benign paroxysmal positional vertigo (BPPV) is one of the most common causes of peripheral vertigo and can manifest in different forms. Multicanal BPPV is rare and difficult to treat. TRV Chair is a method that offers diagnosis and treatment at the same time. The aim was to analyze the outcomes of treatment of multicanal BPPV by means of TRV Chair and compare those results with manual maneuvers. METHODS: Forty-nine subjects aged 26-73 and diagnosed with multicanal BPPV were included. Appropriate maneuvers were performed on affected canals either by TRV Chair or manually. The number of maneuvers required by TRV Chair and manual maneuver were analyzed and compared. RESULTS: The mean number of maneuvers performed until the treatment was completed in manual treatment group was 2.57 ± 1.03, and in TRV group, it was 2.25 ± 1.16. No significant difference was observed between the number of maneuvers performed in either group until the end of the treatment (p > 0.05). DISCUSSION/CONCLUSIONS: Neither TRV Chair nor manual maneuvers were superior to the other in the treatment of multicanal BPPV cases.

The effect of screen time on hearing and balance in 6-16 aged children.

BACKGROUND: The increase in screen time and the decrease in physical- activity cause balance problems as well as many systemic handicaps. AIMS/OBJECTIVES: This study aimed to determine the effect of screen time on balance and the effect of headphone usage time on hearing. METHOD: Thirty-four individuals aged 6-16 years who applied to our clinic with complaints of dizziness and/or balance disorder were included in the study. Participants were divided into 2 groups according to their screen time: Group 1 (4-8 h/day) and Group2(>8 h/day). The other two groups are grouped according to headphone usage time as Group A (2-4 h/day) and Group B (>4hours/day). Pure-tone audiometry, extended high frequency-audiometry, Videonystagmography (VNG) and Computerized Dynamic Posturography (CDP) tests and Pediatric Berg Balance Scale and Visual Analogue Scale were applied to all individuals. CDP scores and pure tone hearing thresholds between groups were compared. RESULTS: A significant difference was observed between Group 1 and Group 2 according to the CDP test (visual, vestibular and composite scores), and according to the VAS-dizziness and PBS (p ≤ .05). Pure tone average and pure tone thresholds at high frequencies were compared between Group A and Group B according to headphone usage time. Pure tone thresholds of Group B were worse at high frequencies than Group A (p ≤ .05). CONCLUSIONS: It has been observed that prolonged screen time may cause balance impairment in children and prolonged use of headphones may affect high-frequency hearing thresholds.

Cochlear synaptopathy causes loudness perception impairment without hearing loss.

Purpose: In this study, the development of a quantitative measurement method to predict long-term auditory adaptation through the stimuli that have been modulated according to different short-term modulation types was aimed to form a psychoacoustic test battery. It might be used in the evaluation process of individuals with hidden hearing loss. Methods: The individuals participating in our study were separated into two groups: high-risk group (n = 39) and low-risk group (n = 30) according to the noise-exposure score. To all participants, auditory brainstem response (ABR), dichotically digit test, Turkish matrix sentence test, otoacoustic emissions test, amplitude modulation detection test, and loudness adaptation test were applied. Stimuli, used in loudness adaptation tests, were provided in three different experiment pairs (experiment 1-2, experiment 3-4, and experiment 5-6). Results: The amplitude of wave I of ABR increased as the intensity level increased in the low-risk group, whereas the amplitude reduced as the intensity level increased in the high-risk group (P < 0.05). When different carrier frequency stimuli were used in amplitude modulation detection test, we found that loudness adaptation was highest at 1 kHz carrier frequency with background noise (P < 0.05). Conclusion: We observed that individuals assumed having hidden hearing loss had high adaptation scores. It was thought that this result might be related to auditory nerve fibers with low spontaneous rate and thus distortion in temporal coding skills might lead to abnormal loudness adaptation, especially with contralateral noise.

Transcutaneous Electric Nerve Stimulation in Chronic Subjective Tinnitus.

OBJECTIVE: It is aimed to determine the therapeutic role of transcutaneous electrical nerve stimulation (TENS) on chronic subjective tinnitus with a randomized and comparative analysis. METHOD: 46 individuals with normal hearing, chronic subjective tinnitus, aged 20-65; randomly divided into the study (TENS therapy) and tje control groups. The control group (n = 23) was informed only about tinnitus, while the study group (n = 23) received TENS therapy (20 sessions in 4 weeks). Before TENS therapy, tinnitus-related evaluations of all participants [tinnitus frequency, loudness, minimum masking level (MMS), residual inhibition (RI)] were made and Tinnitus Handicap Inventory (THI), Visual Analogue Scale (VAS), Short Form 36 (SF-36), and The Quality of Life Scale were applied to the participants. These evaluations and questionnaires were repeated after 4 weeks of the therapy. RESULTS: There was a significant decrease in the tinnitus severity after TENS therapy in the study group (p = 0.003). Moreover, it was found that VAS (loudness and annoyance), THI (functional, emotional and total score), SF-36 (physical function, physical role, pain, general health, vitality, emotional role and social function) values improved compared to before TENS therapy and the difference was significant (p < 0.05). There was no significant difference between the first and last evaluations of the control group (p > 0.05). CONCLUSION: TENS is an effective, practical and reliable therapy method in reducing severity, loudness, and annoyance of tinnitus, and increasing the quality of life in individuals with chronic subjective tinnitus.

Does glutaric aciduria type 1 affect hearing function?

This study aimed to evaluate audiological findings among patients with glutaric aciduria type 1 (GA-1). We used a large test battery for the audiological evaluation of 17 individuals with GA-1 (the study group) and 20 healthy individuals (the control group). Conventional audiometry (0.125-8 kHz), distortion product otoacoustic emissions (DPOAEs) (1, 1.5, 2, 3, 4, 6, and 8 kHz), contralateral suppression of otoacoustic emissions, and auditory brainstem response (ABR) ( 30, 50, 70 and 90 dB nHL) were measured for all participants (n = 37). Mild sensorineural hearing loss was found in 77.47% (n = 13) of the patients with GA-1, and normal hearing thresholds were seen in 23.53% (n = 4). There were three asymptomatic patients at the time of diagnosis [two developed mild mental motor retardation (MMR) and one developed severe MMR during the follow-up], one with a normal hearing threshold and two with mild hearing loss), and 14 symptomatic patients (three with normal hearing thresholds and 11 with mild hearing loss). Seven of the symptomatic patients diagnosed following an encephalopathic crisis required intensive care and showed significantly worse hearing thresholds than those without symptoms [20.86 ± 4.47 vs. 15.44 ± 3.96 decibel hearing level (dB HL), p = 0.039*], while five had mild-to-moderate hearing loss. Acute encephalopathic crisis had a negative effect on hearing function in the symptomatic patients. The emission and contralateral suppression amplitude values of the study group were significantly lower compared to the control group (p < 0.05). The I-V interpeak latency and absolute latencies of ABR waves I, III, and V of the study group were observed to be significantly prolonged and morphologically distorted compared to those of the control group (p < 0.05). Five patients had MMR, and three had moderate MMR; all eight had mild-to-moderate hearing loss. In addition, of the eight patients with mild MMR, four had mild hearing loss. In particular, the morphological findings of ABR waves were significantly worse in the patients with severe and moderate MMR (p < 0.05). There was a significant correlation between a macrocephaly history (12 patients) and hearing loss (p = 0.041*). Magnetic resonance imaging findings were evaluated in all the 17 patients with GA-1, and typical fronto-temporal atrophy and sylvian fissure enlargement were observed. Our findings support that GA-1 is associated with auditory impairment, primarily in symptomatic patients. Adequate audiological test battery evaluation is essential in this context, particularly for symptomatic patients with a history of encephalopathic crises.

Audiological involvement in patients with systemic sclerosis.

OBJECTIVES: The aim of the present study was to evaluate hearing loss in patients diagnosed with systemic sclerosis (SSc) and to investigate the relation between hearing loss, subtypes of the disease, its duration and clinical findings, and antibody positivity. METHODS: The study included 47 patients with SSc and 44 healthy controls. Audiometric, tympanometric, and otoacoustic emission measurements were applied to both groups. RESULTS: The evaluation of the participants medical history showed that among the patients with SSc, 19.1% experienced ear fullness, 27.7% experienced vertigo, and 36.2% experienced tinnitus. Hearing loss was detected in 23.4% of the patients with SSc. The corresponding result was 4.3% in the control group with a statistically significant difference (p = 0.001). Transient-evoked otoacoustic emission amplitude values were significantly lower in the patients' both ears with SSc than the control group (p < 0.005). Duration of disease was significantly longer, and diffusing capacity of the lungs for carbon monoxide values were significantly higher in the patients with SSc and sensorineural hearing loss. CONCLUSIONS: The present study found that the incidence of hearing loss was significantly higher in the study group than in the healthy control group. In addition to other organ involvements, cochlear involvement occurs in these patients, and further studies are required.

Vestibular activities and participation measure: Turkish validity and reliability.

BACKGROUND: International Classification of Functioning, Disability and Health (ICF) has an important role in rehabilitation in terms of assessments. In the field of vestibular rehabilitation, Vestibular Activities of Participation (VAP) measure is the first assessment developed in a perspective of ICF. OBJECTIVE: It was aimed to adapt cross-culturally and analyze psychometric properties of VAP into Turkish Language. METHODS: The VAP was translated into Turkish language by the authors and back translated by a blind native English speaker. The final version was applied to 310 participants. Internal consistency was analyzed with Cronbach's alpha and test-retest reliability analyzed with Intraclass Correlation coefficient (ICC). Validity of the scale investigated with Exploratory and Confirmatory Factor analysis (EFA and CFA). RESULTS: Cronbach's alpha reliability coefficient was found 0.94, and the reliability of the subscales ranged from 0.75 to 0.95; ICC was found 0.94. VAP resulted 8-factor structure and explained 88%of the total variance. In CFA (χ2) / df ratio shows good agreement with 2.472 and the goodness of fit indices of TLI (0.814), CFI (0.893) and RMSEA (0.075) showed acceptable fit. CONCLUSIONS: This study showed that VAP-Turkish version is valid and reliable in Turkish speaking populations, and might be used to determine impact of vestibular disorders on activities and participation.

Evaluation of Speech Recognition Skills in Different Noises with the Turkish Matrix Sentence Test in Hearing Aid Users.

OBJECTIVE: This study aimed to analyze the effectiveness of the Turkish matrix sentence test in evaluating the speech recognition performance of hearing aid users under different noise conditions. METHODS: Speech recognition performance of 42 individuals, 20 to 65 years of age (mean 49.1±14 years) with bilateral sensorineural hearing loss was measured in noise with the Turkish matrix sentence test without a background noise and with headphones. Additionally, the participants' speech recognition thresholds were measured with a matrix test while wearing their hearing aid under three different listening conditions in which the phases of speech and noise stimuli were changed with constant and fluctuating noise. RESULTS: Speech-recognition thresholds were better in fluctuating noise than in constant noise in all listening conditions, and this difference was statistically significant (p=0.02). In both types of noise, speech-recognition thresholds of bilateral hearing aid users (n=29) were lower (better) than those of unilateral hearing aid users (n=13) under three different listening conditions, but there was no statistically significant difference (p=0.67). Speech-recognition thresholds without hearing aids were statistically higher (worse) than those obtained with hearing aids (p=0.001). CONCLUSION: Since the Turkish matrix sentence test gives useful results, this test can be used in the diagnosis, follow-up, and rehabilitation planning of hearing aid users. We observed that speech intelligibility was better, although there were differences among those with hearing loss when the speech test was conducted in fluctuating background noise with the Turkish matrix sentence test.

The effects of diet and physical activity induced weight loss on the severity of tinnitus and quality of life: A randomized controlled trial.

BACKGROUND & AIMS: Subjective tinnitus is the most common and manifest auditory symptom of an existing pathology in the auditory system. Although the effect of obesity on tinnitus is still uncertain, it is known that increased fat tissue increases the severity and symptoms of tinnitus. In this study, it was aimed to evaluate the effect of weight loss through diet and physical activity on tinnitus. METHODS: Forty-six obese subjects diagnosed with tinnitus were randomized into the diet + physical activity (PA) (n = 13), diet (n = 16) and the control groups (n = 17). The anthropometric measurements, tinnitus severity scores, tinnitus handicap inventory (THI) scores and short form quality of life (SF-36) scores of the individuals were recorded and compared at the beginning and at the end of the study. RESULTS: In the diet + PA and diet groups; body weight (diet + PA:-6.5 ± 2.6; diet: -4.1 ± 1) tinnitus severity (diet + PA:-11.0 ± 7.0; diet: -9.0 ± 8.7) and THI scores (diet + FA:-15.0 ± 9.5; diet: -14.0 ± 10.0) significantly decreased compared to the control group (p < 0.01). This decline was more in those with weight loss of ≥5.0% than those with <5.0%. SF-36 score was significantly increased in the diet + PA and diet groups (respectively 10.0 ± 5.5 and 6.0 ± 2.7) compared to the control group (p < 0.05). CONCLUSIONS: Diet and physical activity intervention ameliorated the tinnitus severity and quality of life in obese patients with tinnitus. However to generalize this findings further studies are needed. REGISTERED UNDER CLINICALTRIALS. GOV IDENTIFIER NO: NCT00123456.

Auditory Processing Differences Correlate With Autistic Traits in Males.

Autism spectrum disorder (ASD) has high prevalence among males compared to females but mechanisms underlying the differences between sexes are poorly investigated. Moreover, autistic symptoms show a continuity in the general population and are referred to as autistic traits in people without an ASD diagnosis. One of the symptoms of ASD is sensory processing differences both in sensitivity and perception. To investigate sensory processing differences in autistic traits, we examined auditory and visual processing in a healthy population. We recruited 75 individuals (39 females and 36 males, mean age = 23.01 years, SD = 3.23 years) and assessed autistic traits using the Autism Spectrum Quotient, and sensory sensitivity using the Sensory Sensitivity Scales. Sensory processing in the visual domain was examined with the radial motion stimulus and the auditory domain was assessed with the 1,000 Hz pure tone stimulus with electroencephalography-evoked potentials. The results showed that the auditory sensitivity scores of the males (r aud (34) = 0.396, p aud = 0.017) and the visual sensitivity scores of females were correlated with autistic traits (r vis (37) = 0.420, p vis = 0.008). Moreover, the P2 latency for the auditory stimulus was prolonged in the participants with a higher level of autistic traits (r s (61) = 0.411, p = 0.008), and this correlation was only observed in males (r s (31) = 0.542, p = 0.001). We propose that auditory processing differences are related to autistic traits in neurotypicals, particularly in males. Our findings emphasize the importance of considering sex differences in autistic traits and ASD.

Novel variant p.E269K confirms causative role of PLS1 mutations in autosomal dominant hearing loss.

Auditory reception relies on the perception of mechanical stimuli by stereocilia and its conversion to electrochemical signal. Mechanosensory stereocilia are abundant in actin, which provides them with structural conformity necessary for perception of auditory stimuli. Out of three major classes of actin-bundling proteins, plastin 1 encoded by PLS1, is highly expressed in stereocilia and is necessary for their regular maintenance. A missense PLS1 variant associated with autosomal dominant hearing loss (HL) in a small family has recently been reported. Here, we present another PLS1 missense variant, c.805G > A (p.E269K), in a Turkish family with autosomal dominant non-syndromic HL confirming the causative role of PLS1 mutations in HL. We propose that HL due to the p.E269K variant is from the loss of a stable PLS1-ACTB interaction.

A truncating CLDN9 variant is associated with autosomal recessive nonsyndromic hearing loss.

While the importance of tight junctions in hearing is well established, the role of Claudin- 9 (CLDN9), a tight junction protein, in human hearing and deafness has not been explored. Through whole-genome sequencing, we identified a one base pair deletion (c.86delT) in CLDN9 in a consanguineous family from Turkey with autosomal recessive nonsyndromic hearing loss. Three affected members of the family had sensorineural hearing loss (SNHL) ranging from moderate to profound in severity. The variant is predicted to cause a frameshift and produce a truncated protein (p.Leu29ArgfsTer4) in this single-exon gene. It is absent in public databases as well as in over 1000 Turkish individuals, and co-segregates with SNHL in the family. Our in vitro studies demonstrate that the mutant protein does not localize to cell membrane as demonstrated for the wild-type protein. Mice-lacking Cldn9 have been shown to develop SNHL. We conclude that CLDN9 is essential for proper audition in humans and its disruption leads to SNHL in humans.