POU3F4 and deafness: In the present study, we comprehensively analyzed five prominent deafness-related genes, i.e., GJB2, SLC26A4, mtDNA 12S rRNA, GJB6, and POU3F4, in 114 Tibetan patients from unrelated families in the Tibetan Plateau who experienced early-onset, nonsyndromic hearing impairment, to investigate the molecular etiology of hereditary hearing loss in this region.