摘要
目的 探讨母系遗传性非综合征性耳聋的听力学特征及分子遗传学机制。方法 选择一遗传聋大家系中 4代 41人为研究对象 ,详细询问病史和全身体格检查 ,行系统听力学测试和线粒体DNA(mtDNA)A15 5 5G突变分析。结果 2 0例母系亲属均存在A15 5 5G点突变 ;纯音测听 17例呈程度不等的感音神经性聋 ,双耳对称 ,发病年龄 1～ 5 0岁 ,5例听力近 11年间呈进行性下降 ;声导抗测试均为A型鼓室曲线 ,12耳可在低感觉级引出镫骨肌反射 ;听性脑干反应 (auditorybrainstemresponse,ABR)和瞬态诱发耳声发射测试无蜗后病变证据。 2 1名父系亲属及配偶无听力障碍 ,mtDNAA15 5 5G突变检测阴性。结论 本家系以迟发性进行性耳蜗性聋为特点 ,导致听力损失的内在因素为mtDNAA15 5 5G突变 ,而环境因素和核基因可能也参与了突变体mtDNA表型表达的调节。
Objective To explore audiological features of matrilineal non syndromic deafness and its molecular mechanism. Methods A large family with 41 members having inherited deafness was studied. Complete history and the data of general and otolaryngological examinations were collected. All subjects were screened for mitochondrial DNA A1555G mutation by molecular analysis. Audiological evaluation included pure tone audiometry, auditory brainstem responses and transiently evoked otoacoustic emissions. Results All subjects were in good health generally. Molecular analysis showed that all maternal relatives with or without hearing loss harbored the A1555G mitochondrial mutation. No mutation was found among spouses and paternal relatives. Audiological results showed notable symmetric bilateral sensorineural hearing loss in 17 of 20 maternal relatives, in which 5 cases had a progressive hearing loss in the recent 11 years. The age of appearance of hearing loss ranged from 1 to 50 years. Conclusion All hearing impaired subjects of this family had late onset sensorineural hearing loss. Most of which were progressive. The A1555G mitochondrial mutation in the 12S rRNA gene is responsible for the disorder. Other factors, such as nuclear genes or environmental determinants, may influence the clinical expression of mutant mtDNA.
出处
《中华耳鼻咽喉科杂志》
CSCD
2000年第2期98-101,共4页
Chinese Journal of Otorhinolaryngology
基金
国家自然科学基金资助项目 !(39770402)
关键词
母系遗传性耳聋
听力学
线粒体DNA
基因突变
Hereditary diseases
Hearing loss,sensorineural
DNA, mitochondrial
DNA mutational analysis
Polymerase chain reaction
