[Mutation of Gap junction protein beta 2 gene and treatment outcome of cochlear implantation in cochlear implantation recipients].

Objective: To investigate the Gap junction protein beta 2 (GJB2) gene mutation in cochlear implantation (CI) recipients and the treatment outcome of CI in the CI recipients with GJB2 gene mutation.

Methods: Peripheral blood samples were collected from 253 CI recipients with autosomal recessive non-syndromic hearing impairment (NSHI), 174 males and 79 females, aged (8 +/- 9) (112 months-52.7 years), and 301 children with normal hearing level as controls. PCR was used to detect the GJB2 mutations. The auditory threshold with CI and speech recognition of the CI recipients with GJB2 mutation were compared with those of the CI recipients without GJB2 mutation (control group). Questionnaire survey, with meaningful auditory integration scale (MAIS), categories of auditory performance (CAP), and speech intelligibility rating (SIR), was used for young infants.

Results: Sixty-seven of the 253 CI recipients (26.5%) were found to have GJB2 mutations. One novel mutation, GJB2 235delC/598G > A, was identified. The detection rates of GJB2 mutations in the CI recipients were significantly higher than those among the controls (all P < 0.05). The postoperative outcomes of CI in both the GJB2 gene mutation positive and negative groups were very good, however, without significant differences among these 2 groups (all P > 0.05).

Conclusion: GJB2 gene mutation is one of the major causes for CI recipients with autosomal recessive NSHI. The treatment outcomes of CI recipients with GJB2 gene mutations under 7 years old are satisfying.