Abstract
PURPOSE: To report an interstitial deletion of Xq21.1 in chromosome X in a boy with congenital deafness. METHODS: The proband underwent a thorough physical examination and a detailed audiological and temporal bone computed tomography (CT) scan. Cochlear implantation was performed on the proband, and follow-up was conducted. High throughput sequencing and copy number analysis was made of peripheral blood samples from the proband, family members, and control subjects. RESULTS: Sensorineural hearing loss was present in the boy and temporal bone CT scan showed a bilateral incomplete partition type III anomaly (IP-III). Q21.1 (79.40-83.32 Mb) of chromosome X in the proband had a copy number deletion with a fragment size of about 3.92 Mb. Categories of auditory performance scores and SIR scores of the cochlea in this child improved after surgery. CONCLUSION: Through the analysis of POU3F4, a novel mutation site with potentially pathogenic significance was found.Level of Evidence: 5.