SIX1 (OMIM 601205), as a member of the SIX homeobox transcription factor family, belongs to homologs of the Drosophila?'sine oculis'? gene that expresses primarily in the developing visual system of the fly. The SIX family includes six members (SIX1–SIX6), which share a homologous DNA-binding homeodomain (HD) and a highly conserved protein–protein interacting SIX domain (SD)[1]. These genes are involved in vertebrate and insect development and maintenance of the differentiated state of tissues[1,2,3]. Branchio-oto-renal (BOR) and branchio-otic (BO) syndrome have been reported to be?associated?with?dominant?mutations?in?SIX1,?both are characterized by hearing loss and branchial anomalies, and the former also has the characteristics of renal malformations[4]. In addition, SIX1? mutations may also lead to dominant non-syndromic deafness DFNA23 with variable audiogram?profile[5].