脊髓小脑型共济失调Ⅱ型(CAG)n突变检测研究  

Characteristics of spinocerebellar ataxia type 2 gene mutation dictation in hereditary spinocerebellar ataxia

作　　者：沈璐[1] 唐北沙[1] 汤熙翔[2] 谭斯品[2] 戴和平[2] 潘乾[2] 严新翔[1] 欧阳珊[1] 

机构地区：[1]湖南医科大学附属湘雅医院神经内科,长沙410008 [2]湖南医科大学中国医学遗传学国家重点实验室

出　　处：《中华内科杂志》2000年第4期259-261,共3页Chinese Journal of Internal Medicine

基　　金：湖南省科委课题!(0 1 942 39 3);湖南省卫生厅课题!(95 7)

摘　　要：目的　探讨我国遗传性脊髓小脑型共济失调Ⅱ型 (SCA2 )基因突变特点及临床表型。方法　采用聚合酶链式反应、变性聚丙烯酰胺凝胶电泳和银染技术 ,检测分析 85个中国SCA家系 16 7例患者的SCA(CAG)n。结果　 5个家系 12例患者与 1名无症状者存在SCA2 (CAG)n扩展突变 ,拷贝数为 40～ 47;其余 80个家系 15 5例患者的 (CAG)n拷贝数为 13～ 30。SCA2患者临床以肌张力下降、腱反射减弱和智能障碍多见 ,且异常 (CAG)n拷贝数与发病年龄呈负相关。结论　首次发现中国SCA2基因型 ,但该型在中国少见。Objective To assess the clinical phenotype and characteristics of spinocerebellar ataxia type 2(SCA2)gene mutation in Chinese patients with spinocerebellar ataxia (SCA) Methods The polymorphic(CAG)n copies in SCA2 gene were determined with polymerase chain reaction and denaturing polyacrylamide gel electrophoresis analysis in 167 SCA patients from 85 unrelated Chinese autosomal dominant SCA kindreds Results The mutated SCA2 alleles ranging from 42 to 47 CAG repeats were observed in 12 patients from 5 kindreds, while the normal alleles ranging from 13 to 30 repeats One asymptomatic individual had an expanded allele of 40 CAG repeats The SCA2 patients had mainly cerebella ataxia, dysarthria, hypotonia, decreased reflex, visual loss, swallow difficulty and dementia In addition, the size of expanded (CAG )n copies was inversely correlated with the age of onset of SCA2 Conclusion Although (CAG)n copiers have influence on disease phenotype, they can not be considered as the only predictable index of clinical features

关 键 词：脊髓小脑变性 基因点突变 共济失调 

分 类 号：R744[医药卫生—神经病学与精神病学]