Phenotype analysis of patients of spinocerebellar ataxia with trinucleotide repeat expansion of ATXN8OS gene / 中华神经科杂志

ABSTRACT

Objective:To investigate the clinical and genetic characteristics of patients with CTA/CTG trinucleotide repeat expansion of ATXN8OS gene.Methods:The CTA/CTG trinucleotide repeats of ATXN8OS gene were detected in 1 689 spinocerebellar ataxia cases from Research Center for Movement Disorders and Neurogenetics, Department of Neurology, China-Japan Friendship Hospital in 2005—2017. The correlation between clinical phenotypes and expanded CTA/CTG repeats in the ATXN8OS gene of patients was studied carefully, and compared with 100 healthy controls.Results:Twenty-one patients with pathological CTA/CTG repeat expansion of ATXN8OS gene were collected. Eighteen of them carried the alleles with more than 80 repeats, whose common initial symptom was gait instability, followed by dysarthria and dysphagia with disease progression. Four of the 18 patients presented with head or truncal tremor. The other three patients carried the alleles with the repeats ranging from 70 to 79, whose initial symptom was walking instability, gradually appeared dysarthria, with no dysphagia or tremor. The repeat lengths ranged from 19 to 42 in the 100 healthy controls. The brain magnatic resonance imaging of almost all the patients showed moderate to severe cerebellar atrophy, and some patients with mild atrophy of the brainstem except one case with corpus callosum dysplasia.Conclusions:Most of the patients with CTA/CTG repeat expansion presented with ataxia and dysarthria. Brain magnetic resonance imaging showed significant cerebellar atrophy, suggesting that the mutation is related to SCA8 gene.