Prevalence of Mutations in GJB2, SLC26A4, and mtDNA in Children with Severe or Profound Sensorineural Hearing Loss in Southwestern China

Aim: To study the distribution characteristics of common mutations in the GJB2, SLC26A4, and mtDNA genes in children with severe or profound sensorineural hearing loss (SNHL) in southwestern China. Materials and Methods: A total of 1,164 individuals were recruited to screen for the common GJB2, SLC26A4, and mtDNA mutations by microarrays. Subsequencing for the coding region of the GJB2 gene in the samples without the GJB2 hotspot mutations as well as subsequencing for the exon 1 of the TRMU gene in those samples with the mtDNA hotspot mutations was performed by Sanger sequencing. All mutations were analyzed in association with medical imaging. Results: In this study, 28.43% of all subjects carried mutations. The mutation frequencies in the GJB2, SLC26A4, and mtDNA genes were 17.27%, 7.04%, and 4.12%, respectively. No TRMU mutation was found in the study. The frequency of the mtDNA mutations in the multiethnic minorities was six times that in the Han (11.23% vs. 1.91%; p approaches 0.000) and in the urban ...