Tanaka Eiji, Maruyama Hirofumi, Morino Hiroyuki, Kawakami Hideshi
Department of Epidemiology, Research Institute for Radiation Biology and Medicine, Hiroshima University, Japan.
Hiroshima J Med Sci. 2011 Sep;60(3):63-6.
Spinocerebellar ataxia type 8 (SCA8) is a neurodegenerative disorder characterized by slowly progressive cerebellar ataxia. It is caused by bidirectional expression of (CUG)n expansion in the ATXN80S/ATXN8 gene and (CAG)n expansion transcripts in ATXN8. The diagnosis of SCA8 must be confirmed by the presence of a (CTG)n trinucleotide repeat expansion in the ATXN8OS gene. On the other hand, there are many human genetic diseases that are caused by expansion of short tandem repeats. Since Werner et al proposed a repeat-primed fluorescent PCR to detect large CTG-repeats in myotonic dystrophy, Friedreich ataxia, SCA2, SCA7, SCA10 and SCA12 have been reported. In this study, we applied a fluorescent PCR method for detection of expanded repeats in the ATXN8OS/ATXN8 gene. Although this test cannot give a precise estimate of the size of the expansion, it proved useful for confirming the presence of expansions in SCA8.
8型脊髓小脑共济失调（SCA8）是一种神经退行性疾病，其特征为缓慢进展的小脑共济失调。它由ATXN8OS/ATXN8基因中（CUG）n重复序列的双向表达以及ATXN8中（CAG）n重复序列转录本引起。SCA8的诊断必须通过在ATXN8OS基因中存在（CTG）n三核苷酸重复序列扩增来确认。另一方面，有许多人类遗传疾病是由短串联重复序列的扩增引起的。自从Werner等人提出一种重复引物荧光PCR法来检测强直性肌营养不良中的大CTG重复序列以来，已报道了弗里德赖希共济失调、SCA2、SCA7、SCA10和SCA12。在本研究中，我们应用荧光PCR法检测ATXN8OS/ATXN8基因中的扩增重复序列。虽然该检测不能精确估计扩增的大小，但它被证明对确认SCA8中扩增的存在很有用。
