MJD基因CAG不稳定性扩增与临床研究  

Gene Mutation and Clinical Analysis in Machado-Joseph Disease

作　　者：张宝荣[1] 黄鉴政[1] 夏家辉[2] 丁美萍[1] 朱永良[1] 应智林[1] 潘乾[2] 汤熙翔[2] 姚梅琪[1] 

机构地区：[1]浙江医科大学附属第二医院神经内科,杭州310009 [2]湖南医科大学医学遗传学国家重点实验室,长沙410078

出　　处：《遗传》1999年第6期17-20,共4页Hereditas（Beijing)

基　　金：浙江省教委资助!(资助号: 981072)。

摘　　要：为了解Ｍａｃｈａｄｏ－ Ｊｏｓｅｐｈ 病（ＭＪＤ）基因突变及临床的神经电生理特点， 对１６ 个诊断为遗传性小脑性共济失调（ＳＣＡ）家系的４５ 例病人及３０ 例家系的“正常”人作ＭＪＤ 基因突变分析，检出ＭＪＤ 基因的病人行肢体运动及感觉神经传导速度（ＭＣＶ 及ＳＣＶ）、脑干诱发电位（ＢＡＥＰ），视觉诱发电位（ＶＥＰ）的检查。结果检出１０ 个家系２５ 例病人及１ 例症状前１８ 岁女孩有ＭＪＤ基因突变，ＣＡＧ 三核苷酸重复７３～７９ 次，异常等位基因片段长３８０～４０２ｂｐ，均为杂合子； 正常人ＣＡＧ 三核苷酸重复１８～４０ 次，等位片段长２００～２７０ｂｐ，电生理发现ＭＪＤ 的ＳＣＶ 减慢比ＭＣＶ 明显，而下肢的ＭＣＶ、ＳＣＶ 又较上肢明显，ＢＡＥＰ、ＶＥＰ均有不同程度的潜伏期延长或波的异常；ＭＪＤ 的父亲遗传早于母亲，进展也较块，临床以小脑性共济失调为突出症状，其次为构音障碍、突眼等，肌肉萎缩仅见于晚期病人；ＭＲＩ示小脑萎缩较明显，脑干萎缩并不严重，未见明显的颈髓萎缩。To investigate the gene mutation of clinical and neuroelectrophysiological characteristics in Machado-Joseph disease(MJD). The gene mutation was detected in 45 patients diagnosed as spinocerebellar ataxia(SCA) and 30 “healthy relatives”. Brain stem evoked potentials(BAEP), visual evoked potentials(VEP) and motor conduction velocity (MCV) and sensory conduction velocity (SCV) were performed on MJD. Gene mutations were detected in 25 patients and a 18-year-old girl among 16 families. Trinucleotide repeats of CAG were 73～79. The fragments of abnormal alleles were 380～402bp, and all patients were heterozygous. The copy numbers of normal alleles were 18～40, fragments from 202～270bp. SCV reduction was much obvious compared to MCV, MCV and SCV in lower limb were much more slow than that in upper′s. BAEP, VEP were also delayed in latency. The anticipation in parental sex bias were much more obvioius than that in matental's. Cerebellar ataxia was most severe, the next were dysarthria and bulging eyes. Amytrophy was seen only in bed ridden patients. Cerebellar atrophy was more severe than brain stem, cord atrophy was n′t observed in all MJD.

关 键 词：基因突变 临床电生理 M-J病 小脑性共济失调 

分 类 号：R744.702[医药卫生—神经病学与精神病学]