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Neuro-rehabilitation Approach for Sudden Sensorineural Hearing Loss
Published on: January 25, 2016
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Differences in hearing levels between siblings with hearing loss caused by GJB2 mutations
Masato Fujioka1, Makoto Hosoya2, Kiyomitsu Nara3
1Department of Otorhinolaryngology, Head and Neck Surgery, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo 160-8582, Japan; Department of Otorhinolaryngology, Keiyu Hospital, 3-7-3 Minatomirai, Nishi-ku, Yokohama-shi, Kanagawa 220-8521, Japan; Division of Hearing and Balance Research, National Institute of Sensory Organs, National Hospital Organization Tokyo Medical Center, 2-5-1 Higashigaoka, Meguro-ku, Tokyo 152-8902, Japan.
Auris, Nasus, Larynx
|June 20, 2020
Summary
Siblings with the same GJB2 mutations for hearing loss show varied auditory acuity. Approximately 70% of affected siblings have similar hearing, but 30% experience significant differences.
Area of Science:
- Genetics
- Audiology
- Otolaryngology
Background:
- GJB2 mutations cause autosomal recessive hearing loss (DFNB1).
- Siblings of affected children have a 25% risk of inheriting the same GJB2 mutations.
- Previous research indicates genotype-phenotype correlations in GJB2 mutations.
Purpose of the Study:
- To investigate hearing differences between siblings with identical GJB2 mutations.
- To determine the extent of hearing variation among siblings with the same genetic cause of hearing loss.
Main Methods:
- Auditory evaluation of 12 sibling pairs with identical pathogenic GJB2 mutations.
- Comparison of hearing acuity levels between affected siblings.
Main Results:
- No significant correlation found between average hearing levels of first and second affected siblings.
- Four sibling pairs showed average hearing threshold differences exceeding 30 dB.
- Eight sibling pairs exhibited average threshold differences within 20 dB.
Conclusions:
- Approximately 70% of subsequent siblings with GJB2-mediated hearing loss are expected to have similar auditory acuity to the first affected child.
- About 30% of subsequent siblings may present with average hearing differences greater than 30 dB.
- Significant hearing variability exists among siblings with identical GJB2 mutations, impacting genetic counseling.
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