1型脊髓小脑运动失调(spinocelebellar ataxia typ 1,SCA1)是常染色体显性遗传病,其特征为由于不稳定的CAG三核苷酸重复扩增引起的小脑浦肯野细胞、脊髓小脑后束和选择性的脑干神经元退行性变。为了弄清SCA1突变的发病机理以及三核苷酸重复在小鼠代际间的遗传稳定性,作者用表达带有正常或CAG反复扩增序列的人类SCA1基因的转基因小鼠进行研究。两种基因在从亲代向子代的遗传过程中都是稳定的。表达无CAG扩增序列的 Spinocerebellar ataxia type 1 (SCA1) is an autosomal dominant genetic disease characterized by cerebellar Purkinje cells, spinocerebellar tract and cerebellar spinous processes caused by unstable CAG trinucleotide repeat amplification Selective brain stem degeneration. To understand the pathogenesis of SCA1 mutations and the genetic stability of trinucleotide repeats in mouse offspring, the authors studied the transgenic mice expressing the human SCA1 gene with normal or CAG repeat amplification sequences. Both genes are stable in the genetic process from parent to offspring. Expression of CAG-amplified sequences