Auditory Brainstem Responses in Gap Junction Beta 2 (GJB2) 35delG Mutation Carriers

Objective: In the present study, the eight nerve and inner hair cells of the Gap Junction Beta 2 (GJB2) 35delG mutation carriers with normal hearing were evaluated by the Auditory Brainstem Response (ABR) technique. Materials and Methods: The ABR tests were performed in 90 dB nHL, using 11 and 60/s rates and 3 polarities. Twenty-three subjects who carry GJB2 35delG mutation were compared to 25 non-carriers. Results: Significant difference in air conduction thresholds at all frequencies was found in the left ears of both groups. In case of the right ears, significant differences were observed at all frequencies except 2 and 14 kHz. Carriers effect on ABR I, Ill and V wave latencies, and I-III, III-V and I-V interpeak latencies were not observed (p<0.05). Conclusion: It was concluded that the GJB2 35delG mutation did not cause any damage of inner hair cells and dysfunction of the eighth nerve in carriers.