Background:The molecular genetic research showed the association between X-linked hearing loss and mutations in POU3F4.This research aimed to identify a POU3F4 mutation in a nonsyndromic X-linked recessive hearing loss family.Methods:A series of clinical evaluations including medical history,otologic examinations,family history,audiologic testing,and a high-resolution computed tomography scan were performed for each patient.Bidirectional sequencing was carried out for all polymerase chain reaction products of the samples.Moreover,834 controls with normal hearing were also tested.Results:The pedigree showed X-linkage recessive inheritance patt,and pathogenic mutation (c.499C＞T) was identified in the proband and his family member,which led to a premature termination prior to the entire POU domains.This mutation co-segregated with hearing loss in this family.No mutation ofPOU3F4 gene was found in 834 controls.Conclusions:A nonsense mutation is identified in a family displaying the pedigree consistent with X-linked recessive patt in POU3F4 gene.In addition,we may provide molecular diagnosis and genetic counseling for this family.