Genetic characteristics in children with cochlear implants and the corresponding auditory performance

Abstract

Objectives/hypothesis: To explore the genetic characteristics of children with cochlear implants (CIs) and to correlate the auditory performance after implantation to the genetic diagnosis of children with CIs.

Study design: Prospective cohort study.

Methods: Mutations of four common deafness-associated genes, GJB2, SLC26A4, the mitochondrial 12S rRNA gene, and OTOF, were screened in 743 unrelated children with idiopathic sensorineural hearing impairment, including 180 and 563 children with and without CIs, respectively. The allele frequencies and audiologic features were compared between both groups. The Categories of Auditory Performance (CAP) scores at 3 years after implantation were then analyzed according to the genotypes.

Results: A definitive genetic diagnosis was made in 37 (20.6%) of the 180 CI children. A significant difference in allele frequencies between CI and non-CI children was found in GJB2 mutations (chi-square test, P < .01), but not in SLC26A4 mutations, mitochondrial 12S rRNA mutations, or OTOF mutations (all P > .05). Further analysis revealed that the difference might have resulted from distinct audiological features in each group. Among the 110 CI children who had received more than 3 years of rehabilitation after implantation, the 35 children with mutations had better CAP scores than the 75 children without mutations.

Conclusions: A significant prevalence of genetic mutations was identified in children with CIs, suggesting the need for routine genetic assessments. The frequencies of common deafness-associated mutations were different between children with and without CIs. The presence of genetic mutations was associated with an excellent long-term auditory performance outcome after implantation.