| Human deafness is a major medical and public health concern. It has beenestimated tha approximately 70 million people worldwide have a hearing loss ofat least 55dB, and 50% of deafness in newborns has a genetic basis. In 70% ofthese cases, the hearing impairment is described as "nonsyndrdromic" because it isnot associated with other clinical manifestations. The genetics of human deafnessis complex and heterogeneous. The genetic heterogeneity of this disorder has beenwell established as 80 nonsyndromic hearing loss loci have been mapped and 17genes have been cloned to date. The continued identification of genes associatedwith hearing loss may provide an effective means of uncovering essentialcomponens of the auditory system and promise an increased understanding of themolecular basis for sound ·transduction. We have ascotained 21 familiessegregating nonsyndromic sensorineural hearing loss. To map the locusrerponsible for hearing loss in deafness family, we firstly excluded knowndeafness loci. The study was composed of three parts below:Part 1. Family studies and SIMLINK analysisObjective To determine the pattern of inheriance and phenotype of thecollected family and to estimate the power of a proposed linkage study. MethodsThe pedigree was constructed on the basis of information obtained fromquestionnaires and interviews. The members in 21 families were interviewedregarding their medical history and family relationships and underwent anexamination to exclnde signs of syndromic hearing impairment. Pure-toneaUdiOmetry tymPanometry and ABR wer pwted. The pattem of inhedancewas detMd by pedgree and segretio analySis. The SWIN'K soforareboion 4.l2) was used to estiInat the prObability of deteCtio of Me in ourftally Result8 (1) Pedigree anaiySis: Nons~c autosoInal dominathereditary hearin boainnen was foun in l1 bolies, and nonSyndrondcWsOInai recessbe hereditary hearin boainnen was shOWed in 7 bolies. Thelast 3 drilles belong to maemal tranSmited boes ofdethes. (2) Phenope: All21 fchlies belong to nonsyndroInic heedny hearin boainnen. Thepleres wer summd uP in the age of onset, seVerity and Progression of thehearin loss. (3) The pWe of the tri boly: m hail shOWd nonsyndrndc autosomai doIninan hereditny wi boainnat. The heahag lOsswas sensorineUI, highfrequerey, moderatetormderatel sever andProgresion. The onsot age was abOat 20 years old. The hearing loss was not--cal and tallatera invOlvement in 12 persons. (4) SlMLINK analySis hadshOWn tha the third ftally could genera a maXtw LOD score of 3.781.ConcIUsion The gene maPing can cny out in the ch hailPart 2. Genthe analyis of Anown nonmpdrmtc autosoma! dominant~ess haObjective TO get the gontyPes of 22 bown nonSyndroe autosomaldomjnan dethess loci. Methods DNA was isolated frOm blood samPles in 35boly memers and 50 nonnal subeCts. STR genetic markers wer analyZed bypolymerase chain reaction and popee ge eleCtrOPhoreSis using thesM procM. PN soforare was used tO cMate the allee fre~es,heerozygOsity PIC and HardyWeinerg tes of 10 loci in nonnal persons.Reults (l) We found that 10, 9, 8, 7, 7, 6, 6, 6, 5 aJleles wer Observed atD6S287, D8S1l32, D13Sl275, D15S130, D1S2726, D4S3038, D2S2380,D22S282, D14S1042, D7S529 lOci' reSPW The diforutiOnS of genopesin Wse Han wer in accotae with HardyWeinerg equllibrium, and thePIC was more than 0.7 fOr thetD. rerpectively (2) Gettin the genotyPe of 35meders of the M boly: No diWe of the dichon of alldss betWentheCted and untwd drilies was shOWed. ConclUsion The results indiatedtha these 22 STh loci can be used fOr ~c analyis.he i Linkag an~ in taopilyObjecthr To detennin whethe or no the gere of the third ftallyMe to the 22 bown dethess lOci. Methods boToint linkae analySishas been done using for PrOgram of bo pahage 5.2. Lods wer obtainedby differen gen freqUenCy oT allele boy Reults (1) The results of Lodswer no thectea by the diW gene ffeH or thele hempy (z)...
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