Mutesa Léon, Pierquin Geneviève, Segers Karin, Vanbellinghen Jean François, Gahimbare Laetitia, Bours Vincent
Medical Genetics Laboratory, National University of Rwanda, CHU of Butare, Rwanda.
J Trop Pediatr. 2008 Oct;54(5):350-2. doi: 10.1093/tropej/fmn034. Epub 2008 May 22.
Spinocerebellar ataxia type 2 (SCA2) is an autosomal dominant neurodegenerative disease that results from the expansion of an unstable trinucleotide CAG repeat encoding for a polyglutamine tract. In normal individuals, alleles contain between 14 and 31 CAG repeats, whereas the pathological alleles have more than 35 CAG repeats. The clinical phenotype of SCA2 includes a progressive cerebellar ataxia with additional features such as ophthalmoplegia, extra-pyramidal or pyramidal signs and peripheral neuropathy. We report a SCA2 large African family with several affected individuals. A major pathological allele carrying 43 CAG repeats was identified in the proband. To our knowledge, this is a first report of a SCA disorder described in Central African patients, thus indicating the need to consider this diagnosis in young African ataxic patients.
2型脊髓小脑共济失调(SCA2)是一种常染色体显性神经退行性疾病,由编码多聚谷氨酰胺序列的不稳定三核苷酸CAG重复序列扩增引起。在正常个体中,等位基因含有14至31个CAG重复序列,而病理性等位基因具有超过35个CAG重复序列。SCA2的临床表型包括进行性小脑共济失调,并伴有诸如眼肌麻痹、锥体外系或锥体束征以及周围神经病变等其他特征。我们报告了一个有多个受累个体的SCA2非洲大家庭。在先证者中鉴定出一个携带43个CAG重复序列的主要病理性等位基因。据我们所知,这是首次报道在中非患者中描述的SCA疾病,因此表明在年轻的非洲共济失调患者中需要考虑这一诊断。