Analysis Of Sensitive Deafness Genes In 147 Cases Of Patients With Moderate Or Severer Sensorineural Deafness In Hainan

ObjectiveDetecting the mutation rate of sensitive deafness genes of patients with moderate or severer sensorineural deafness in Hainan and analysing the relationship of genotype and phenotype,to provide information for the epidemiological investigation of deafness genes.Methods1.147 patients with with moderate or severer sensorineural deafness from September 2017 to December 2018 were enrolled in this study.Doing Questionnaires and audiological examinations were collected in these patients.Part of them received scan temporal bone CT and cranial MRI.2.The peripheral blood samples of 147 patients were collected for 3-5 mL.Nine mutation sites of four sensitive deafness genes were detected using the deafness susceptibility gene detection kit(PCR+conduction hybridization).They were GJB2(176 del16,35 del G,235 del C,299 del AT)of congenitaldeafness gene,SLC26A4(IVS7-2 A > G,2168 A > G)of enlarged vestibular aqueduct syndrome gene,mtDNA(12SrRNA 1555 A > G,12 SrRNA 1494C > T)of drug-induced ear gene and GJB3(538C > T)of late-onset deafness.3.Analyzing the experimental results of gene examination and clinical data of deafness.ResultsThere were 147 patients with moderate or severer sensorineural deafness,96 males and 51 females.The age distribution ranged from 7 months to 55 years old.There were 32 cases of moderate hearing loss,51 cases of severe hearing loss and 64 cases of severe hearing loss.All of them were bilateral hearing loss.There were 13 cases with family history and 4 cases having used aminoglycoside antibiotics.Temporal bone CT showed vestibular aqueduct enlargement with or without varying degrees of mondini malformation or(and)vestibular enlargement in 4 cases.SLC26A4 gene mutation was detected in all cases,and the loss was bilateral extremely severe deafness.Among 147 cases,33 gene mutations were totally detected(22.45%,33/147).The mutation rates from high to low were respectively GJB2(14.29%,21/147),SLC26A4(4.76%,7/147),12 S rRNA(2.72%,4/147),GJB3(0.68%,1/147),and the most common mutation sites was 235 delC.Biallelic mutations were detected in 12 cases(36.36%,12/33),including 7 homozygous mutations,3 compound heterozygousmutations and 1 homogeneous mutations.Single allele mutations were detected in 21 cases(63.63%,21/33).Conclusions1.The detection rate of four common genes in sporadic non-syndromic deafness patients in Hainan was 22.45%,and the mutation rate of GJB2 gene was the highest,followed by SLC26A4,and GJB3 mutation rate was the lowest,which provides information for the epidemiological investigation of deafness genes.2.The detection rate of SLC26A4 gene mutation in LVAS patients was100%.LVAS patients were usually associated with mondini malformation and vestibular enlargement,and most of the hearing loss is bilateral extremely severe deafness.