强直性肌营养不良一家系的临床和致病基因初步分析

目的:探讨浙江台州地区一个强直性肌营养不良(myo tonic dystrophy,DM)汉族家系的临床表现和分子遗传学基础.方法:分析 该家系44例成员中8例(包括先证者Ⅲ13)临床确诊为DM患者的临床表现,以及5例患 者和6例无症状成员的肌电图表现,并对7例DM患者(除Ⅱ6外)的DNA样品进行DM 1和DM22个位点PCR扩增、琼脂糖电泳检测,对克隆产物进行测序. 结果: 该家系患者除有肌强直、肌萎缩等表现外;心电图检查:心脏传导阻滞(7/8);裂 隙灯检查:白内障(6/7);肌电图检查:患者组有强直电位发放(5/5),无临床症状成员也 存在肌源性损害(5/6);但该家系无DM1位点(CTG)n和DM2位点(CCTG )n的重复数增加.结论:强直性肌营养不良可能存在新的致病基因位 点.

Clinical and genetic analysis of a pedigree of myotonic dystrophy disease

OBJECTIVE: To investigate the clinical manifestations and to make genetic analysis in a pedigree with myotonic dystrophy disease. METHODS: The proband and available family members were identified by neurological examination. The clinical manifestation of 8 patients (including the proband) was analyzed; the electromyographic data of 5 patients were compared with 6 other family members. Blood samples were obtained from the 7 patients of the family (excepting II6). DM(1) and DM(2) gene were amplified by PCR, tested by agarose electrophoresis, then analyzed by genetic analyzer. RESULTS: Myotonia and muscle weakness were the main manifestations associated with heart block (7/8) and cataract(6/7). Electromyologram showed myopathic abnormalities not only in patients but also in other members of the family (5/6). The CTG repeats in DM1 and CCTG repeats in DM2 were all in normal range. CONCLUSION: There likely to be new mutants in this DM pedigree and further study is needed.