A Pedigree Study of Hereditary Auditory Neuropathy with Optic Atrophy / 听力学及言语疾病杂志

ABSTRACT

Objective To investigate the genetic causes of auditory neuropathy with optic atrophy in a family.Methods The proband's medical history and family history were inquired in detail,and relevant clinical examina-tions were performed to confirm the diagnosis of auditory neuropathy with optic atrophy,and the genetic pedigree of the family was drawn.Peripheral blood of proband(Ⅲ-7)was collected for whole exome sequencing,and the patho-genicity of the detected mutations were interpreted.Blood samples of proband's wife(Ⅲ-8),eldest daughter(Ⅳ-7),second daughter(Ⅳ-9)and son(Ⅳ-10)were tested for mutation sites by Sanger sequencing.Combined with clinical manifestations and examination results,the family was studied.Results The genetic pattern of this family was autosomal dominant.The proband showed decreased visual acuity at the age of 19,bilateral sensorineural deaf-ness at the age of 30,and decreased speech recognition rate.Among 20 members of the family of 5 generations,10(2 deceased)showed similar symptoms of hearing and visual impairment.Proband(Ⅲ-7),eldest daughter(Ⅳ-7)and son(Ⅳ-10)underwent relevant examination.Pure tone audiometry showed bilateral sensorineural deafness.ABR showed no response bilaterally.The 40 Hz AERP showed no response in both ears.OAE showed responses in some or all of the frequencies.No stapedial reflex was detected.The eye movement of Ⅲ-7 and Ⅳ-10 were reasona-ble in all directions,and color vision was normal.Ocular papilla atrophy was observed in different degrees in fundus examination.OCT showed thinning of optic disc nerve fibers in both eyes,and visual evoked potential showed pro-longed P100 wave peak.They were diagnosed as hereditary auditory neuropathy with optic atrophy.A mutation of the OPA1 gene c.1334G＞A(p.Arg445His,NM_015560.2)at a pathogenic locus on chromosome 3 was detected by whole exon detection in Ⅲ-7.The results of generation sequencing analysis showed that the OPA1 gene c.1334G＞A(p.Arg445His,NM_015560.2)mutation of chromosome 3 was also found in Ⅳ-7 and Ⅳ-10.Meanwhile,the gen-otypes of Ⅲ-8 and Ⅳ-9 were wild homozygous,that is,no mutation occurred.Conclusion The OPA1 c.1334G＞A(p.Arg445His,NM_015560.2)mutation site might be the pathogenic mutation in this family.