Lee Won Yong, Jin Dong Kyu, Oh Myung Ryurl, Lee Ji Eun, Song Seng Mi, Lee Eun Ah, Kim Gyeong-Moon, Chung Jin Sang, Lee Kwang Ho
Department of Neurology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
Arch Neurol. 2003 Jun;60(6):858-63. doi: 10.1001/archneur.60.6.858.
By genetic analysis, the CAG repeat expansion has been established in spinocerebellar ataxia (SCA) types 1, 2, 3, 6, and 7. Despite the genetic differentiation of SCA, the characterization of the phenotypes of various SCAs has been challenging for better clinical diagnosis.
To analyze the frequencies and the clinical manifestations of SCA1, SCA2, SCA3, SCA6, and SCA7 in Korean patients.
We performed genetic analysis in 253 unrelated Korean patients with progressive cerebellar ataxia. We compared the frequencies, inheritance patterns, and various clinical manifestations of patients with genetically confirmed SCA.
Among the 52 patients with expanded CAG repeat, the most frequent SCA type was SCA2, followed by SCA3, SCA6, SCA1, and SCA7. Nine patients (17%) had a negative family history of ataxia, mostly in SCA6. There were characteristic clinical features such as hypotonia and optic atrophy for SCA1; hyporeflexia for SCA2; nystagmus, bulging eye, and dystonia for SCA3; and macular degeneration for SCA7. Interestingly, 4 patients (1 with SCA2, 1 with SCA3, and 2 with SCA6) were misdiagnosed as having multiple-system atrophy because of the absence of family history and the presence of parkinsonism and urinary incontinence.
This study provides a detailed analysis of the clinical characteristics of the genetically defined CAG-repeat SCAs in Korean patients. Although phenotypes were heterogeneous, some clinical features may be helpful for clinical diagnosis. However, genetic studies for SCA are needed despite uncertain family history or the presence of atypical clinical features causing misdiagnosis as atypical parkinsonism.
通过基因分析，已确定1型、2型、3型、6型和7型脊髓小脑共济失调（SCA）存在CAG重复序列扩增。尽管SCA存在基因差异，但对各种SCA表型进行特征描述以实现更好的临床诊断仍具有挑战性。
分析韩国患者中SCA1、SCA2、SCA3、SCA6和SCA7的发生频率及临床表现。
我们对253例无亲缘关系的韩国进行性小脑共济失调患者进行了基因分析。我们比较了基因确诊的SCA患者的发生频率、遗传模式及各种临床表现。
在52例CAG重复序列扩增的患者中，最常见的SCA类型是SCA2，其次是SCA3、SCA6、SCA1和SCA7。9例患者（17%）共济失调家族史为阴性，主要是SCA6患者。SCA1有肌张力减退和视神经萎缩等特征性临床特征；SCA2有反射减退；SCA3有眼球震颤、突眼和肌张力障碍；SCA7有黄斑变性。有趣的是，4例患者（1例SCA2、1例SCA3和2例SCA6）因无家族史以及存在帕金森症和尿失禁而被误诊为多系统萎缩。
本研究对韩国患者中基因定义的CAG重复序列SCA的临床特征进行了详细分析。尽管表型具有异质性，但一些临床特征可能有助于临床诊断。然而，尽管家族史不确定或存在导致误诊为非典型帕金森症的非典型临床特征，仍需要对SCA进行基因研究。
