OBJECTIVETo investigate whether GJB3 and GJB2 interaction to produce a deafness phenotype in a digenic mode of inheritance in Chinese deafness population.

METHODSA series of 108 patients with severe or profound hearing loss carrying one heterozygous GJB2 pathogenic mutation were sequenced for GJB3 coding region, which compared with the data of control group.

RESULTSThree GJB3 missense variants including V84I, A194T and N166S, and four GJB3 nonsense mutation were detected. N166S and A194T were considered as pathogenic which cause nonsyndromic autosomal recessive hearing loss and V84I was considered as polymorphisms in Chinese population. The two patients who carried N166S and A194T respectively in one allele also carried GJB2 235delC mutation in other allele, while the other patient who carried A194T in one allele also carried GJB2 299_300delAT mutation in other allele.

CONCLUSIONSGJB3 and GJB2 might interact to produce deafness in a digenic mode of inheritance, but the point need to be proved in further study.