线粒体内膜易位酶8A基因新突变导致耳聋肌张力障碍综合征一家系  

A novel mutation in the translocase of inner mitochondrial membrane 8 homolog A gene in a family with Mohr-Tranebjaerg syndrome

作　　者：王璐[1] 张巍[1] 刘玉和[2] 吕鹤[1] 王朝霞[1] 袁云[1] 

机构地区：[1]北京大学第一医院神经内科,100034 [2]北京大学第一医院耳鼻喉科,100034

出　　处：《中华神经科杂志》2013年第4期243-246,共4页Chinese Journal of Neurology

摘　　要：目的报道1个耳聋肌张力障碍综合征（Mohr-Tranebjaerg syndrome，MTS）家系的临床和基因突变特点。方法收集1个MTS家系的临床资料，对该家系先证者（Ⅲ5）行视、听觉诱发电位，纯音测听，瞬态诱发耳声发射和畸变产物耳声发射检查，同时对Ⅲ，及该家系健康成员I2、Ⅱ4、Ⅱ6进行线粒体内膜易位酶8A（TIMM8A）基因测序。结果Ⅲ，男性，2岁后渐出现听力障碍、讲话欠清、双手指伸开困难和行走姿势异常。家系中Ⅲ1、Ⅲ2、Ⅲ3在2岁后均出现听力障碍，I2、Ⅱ2、Ⅱ4和Ⅱ6分别在12岁左右出现视力轻度下降。Ⅲ，视觉诱发电位示双侧P100潜伏期延长，纯音测听示双耳重度感音神经性聋，听觉诱发电位双耳均无波形出现，耳声发射检查在双耳均未引出。基因测序示m，TIMM8A基因内含子存在c．133-2delA剪切突变，同时I2、Ⅱ4、Ⅱ6均检测到该位点突变。结论MTS存在TIMM8A基因新突变。除感音神经性耳聋外，该病其他症状的发展在同一家族不同患者间存在明显差异，轻度视神经损害可在女性基因携带者中出现。Objective To report the clinical and genetic features in a family with Mohr-Tranebjaerg syndrome （MTS）. Methods After collecting clinical data of the family, visual and auditory evoked potentials ,pure tone audiometry, transient evoked otoaeoustie emissions and distortion product otoacoustic emissions were carried out in proband （III5 ）- The translocase of inner mitochondrial membrane 8 homolog A （TIMM8A） gene was sequenced in proband, I 2, II 4 and II 6. Results III5, a 15-year-old boy presented with deafness, slurred speech, difficulty in finger extension and dystonia gradually since 2 years old. IIIl, III2 and III3 presented with deafness at the age of 2. I2, II2, II4 and II6 showed mild decreased visual acuity at the age of 12. Visual evoked potentials revealed prolonged P100 latency in both eyes. Pure tone audiometry revealed severe sensorineural hearing loss. The auditory evoked potentials showed no wave in the bilateral ears. Otoaeoustic emissions were not elicited bilaterally. A novel e. 133-2delA mutation in TIMM8A gene was identified in III5, I 2, II 4 and II6. Conclusions We confirm the MTS caused by a novel e. 133- 2delA mutation in TIMM8A gene. Except for the deafness, the development of other symptoms of the disease vary obviously from case to case in the same family. The female carriers with mild lesion of optic nerves.

关 键 词：张力失调 智力障碍 视神经萎缩 聋盲障碍 膜转运蛋白质类 突变 

分 类 号：R764[医药卫生—耳鼻咽喉科]