简介：Objective:Electrocochleography(ECochG)isvaluabletodiagnoseMeniere'sdiseaseobjectively.TheaimofthepresentstudywastoprovidepreliminarynormativedataforECochGamongAsianadults.Theinfluencesofethnicity(MalayversusChinese)andgenderonECochGresultswerealsostudied.Methods:Twenty-twoMalayadults(10menand12women)andtwentyChineseparticipants(10menand10women)agedbetween20and49yearsparticipatedinthisstudy.ExtratympanicECochG(ET-ECochG)wasrecordedaccordingtostandardnon-invasiveprocedure.Summatingpotential(SP)amplitude,actionpotential(AP)amplitudeandSP/APratiowereanalyzedaccordingly.Results:ET-ECochGresultswerefoundtobecomparablebetweenleftandrightears(p>0.05).NonotabledifferencesinET-ECochGresultswerefoundbetweenMalayandChinesegroups(p>0.05).NosignificantinfluenceofgenderonET-ECochGoutcomeswasalsonoted(p>0.05).ThederivednormativedataforAsianadults(84ears)areconsistentwithpreviousreports.Conclusion:ThepresentstudyprovidespreliminarynormativedataforET-ECochGamongAsianadults.TheECochGcomponentsdonotappeartobeinfluencedbyeitherethnicityorgender.ThederivednormativedatacanbeusedforclinicalapplicationsandasthereferenceforfuturestudiesinvolvingAsianpopulation.

简介：MutationsintheGJB2genearethemostfrequentlyfoundmutationsinpatientswithnonsyndromichearingimpairment.However,themutationspectrumandprevalenceofmutationsvaryamongdifferentethnicgroups.Everyyear,30,000babiesarebornwithcongenitalhearingimpairmentinChina.Inordertoprovideappropriategenetictestingandcounselingtothefamily,weinvestigatedthemolecularetiologyofnonsyndromicdeafnessin135unrelatedschoolchildrenattendingChifengMunicipalSpecialEducationSchoolinInnerMongolia,China.ThecodingexonoftheGJB2genewasPCRamplifiedandsequenced.Inaddition,the12SrRNAgeneandtRNAser(UCN)ofmitochondrialgenomewerescreenedformutationsresponsibleforhearingimpairment.SixtyfourGJB2mutantalleles,including60confirmedpathogenicallelesand4unclassifiedvariants,wereidentifiedin31.1%(42/135)ofthesubjects.Twentytwosubjectscarriedtwopathogenicmutationsand20subjectscarriedonemutantallele,includingonesubjectwithoneautosomaldominantmutation.The235delCwasthemostcommonmutationaccountingfor65.6%(42/64)GJB2mutantalleles.WhencomparedtootherAsianpopulations,oursubjectcohorthadhigherfrequencyof235delCmutationthantheJapanesepopulation.TheGJB2mutantallelesaccountfor23.7%(64/270)ofallchromosomesresponsiblefornonsyndromichearingimpairment.Testingofthe4mostprevalentdeleteriousframeshiftmutations(235delC,299_300delAT,176_191del16,and560_605ins46)inthiscohortdetected90%ofallGJB2mutantalleles.TheseresultsdemonstratethateffectivegenetictestingoftheGJB2geneforpatientsandfamilieswithnonsyndromichearingimpairmentispossibleintheChinesepopulation.Sincethemostcommon309kbGJB6deletionisnotdetectedandonlyone1555A>GmutationinmitochondrialDNAisdetectedinourpatients,investigationofmutationsinothernucleargenesand/orenvironmentalfactorsresponsiblefornonsyndromichearingimpairmentintheChinesepopulationis