Abstract:Objective:To study the molecular etiology of a hereditary hearing loss family associated with vestibular dysfunction by analyzing genetic pattern,phenotypic characteristics and pathogenic gene. Methods:Clinical data (medical history,audiological and vestibular function examination,as well as imaging examination) were collected. By target gene capture and massively parallel sequencing technologies,104 species and genes related to hereditary hearing loss and 3 microRNAs in probands of the pathogenic mutation were screened. Furthermore,we analyzed the gene coding region sequence of candidate mutations. Results:C.1458C>G (p.T352S) heterozygous mutations were found in the exon 11 of the COCH gene. Ⅰ2,Ⅱ1,Ⅱ5,Ⅱ9,Ⅱ13 and Ⅳ1 showed the same heterozygous mutation. Ⅱ11 and Ⅲ1 showed that the mutation was homozygous for this mutation,which means that there was no co-segregation,therefore,the possibility of pathogenic mutation in the family could be eliminated. No other mutations were found in the sequence of all 12 exons of the Ⅲ14 COCH gene. Conclusion:This family has an autosomal dominant disorder associated with vestibular dysfunction. However,the initial screening results were not found to be associated with the known deafness genes,including the COCH gene. Therefore,the molecular etiology of this family may be a new gene mutation.