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Unusual phenotype in 35delG mutation: a case report.
Cem Yeral1, Lutfu Seneldir2, Arzu Hediye Karakoc3
1Faculty of Health Sciences, Department of Audiology, İstanbul University-Cerrahpaşa, Istanbul, Türkiye. cem.yeral@gmail.com.
Journal of Medical Case Reports
|May 11, 2024
Summary
The GJB2 gene
Area of Science:
- Genetics
- Otolaryngology
- Molecular Biology
Background:
- GJB2 gene mutations, encoding connexin 26, are a primary cause of autosomal recessive nonsyndromic hearing loss.
- The 35delG mutation is a common GJB2 mutation, typically causing prelingual, bilateral, nonprogressive sensorineural hearing loss.
Observation:
- An 18-year-old Turkish female presented with a heterozygous 35delG mutation.
- This patient exhibited postlingual, unilateral, progressive, and fluctuating profound-sloping sensorineural hearing loss.
Findings:
- The observed phenotype significantly differed from the typical presentation associated with the 35delG mutation.
- This case highlights variability in GJB2 mutation expression.
Implications:
- The 35delG mutation's phenotypic expression in hearing loss can be atypical.
- Audiologic manifestations of GJB2 mutations may vary, requiring comprehensive diagnostic approaches.
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