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Case Reports
. 2024 May 12;18(1):241.
doi: 10.1186/s13256-024-04559-3.

Unusual phenotype in 35delG mutation: a case report

Cem Yeral  1 , Lutfu Seneldir  2 , Arzu Hediye Karakoc  3 , Aleyna Sap  3 , Oguz Yilmaz  3
Affiliations
Case Reports

Unusual phenotype in 35delG mutation: a case report

Cem Yeral et al. J Med Case Rep. .

Abstract

Background: Mutations in the GJB2 gene, which encodes the protein connexin 26 and is involved in inner ear homeostasis, are identified in approximately 50% of patients with autosomal recessive nonsyndromic hearing loss, making it one of the primary causes of prelingual nonsyndromic hearing loss in various populations. The 35delG mutation, one of the most common mutations of the GJB2 gene, usually causes prelingual, bilateral mild to profound, nonprogressive sensorineural hearing loss.

Case presentation: We present an unusual case of an 18-year-old Turkish female with heterozygous 35delG mutation and postlingual, profound-sloping, progressive and fluctuating unilateral sensorineural hearing loss. The phenotype is different from the usual findings.

Conclusions: The 35delG mutation causing hearing loss may not always be reflected in the phenotype as expected and therefore may have different audiologic manifestations.

Keywords: 35delG mutation; GJB2; Genetic hearing loss; Unilateral progressive hearing loss.

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Conflict of interest statement

The authors have no conflicts of interest to declare.

Figures

Fig. 1
Fig. 1
Pure tone audiometry configurations
Fig. 2
Fig. 2
Wave morphologies of the Auditory Brainstem Response test
See this image and copyright information in PMC

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