Analysis of the clinical features and genetic mutation of spinocerebellar ataxia type 6 from Chinese kindreds / 临床神经病学杂志

ABSTRACT

Objective To study the clinical features and genetic mutation frequency of spinocerebellar ataxia (SCA) type 6 from Chinese kindreds. Methods The SCA6 (CAG)n trinucleotide repeat mutations were detected using polymerase chain reaction (PCR) and polyacrylamide gel electrophoresis (PAGE) techniques in 330 patients with autosomal dominant SCA from 160 kindreds and 77 sporadic SCA patients, and the abnormal alleles fragments were sequenced by ABI377 DNA sequencing machine. The clinical features were assessed and cranial MRI examinations were performed in these patients.Results 6 patients from 4 SCA6 Chinese kindreds had abnormal SCA6 alleles with CAG repeat expanded to 25 and 26, respectively, of which 2.5% was about the positive rate, while CAG repeat of normal SCA6 allele ranged from 5 to 17. The basic characteristics of SCA6 patients were slowly progressive cerebellar ataxia and purely cerebellar atrophy.Conclusion SCA6 is one seldom subtype of SCA in Chinese patients with its characteristics both in clinic and imaging in contrast to other subtypes.