High germinal instability of the (CTG)n at the SCA8 locus of both expanded and normal alleles.

ABSTRACT: The autosomal dominant spinocerebellar ataxias (SCAs) are a group of late-onset, neurodegenerative disorders for which 10 loci have been mapped (SCA1, SCA2, SCA4-SCA8, SCA10, MJD, and DRPLA). The mutant proteins have shown an expanded polyglutamine tract in SCA1, SCA2, MJD/SCA3, SCA6, SCA7, and DRPLA; a glycine-to-arginine substitution was found in SCA6 as well. Recently, an untranslated (CTG)n expansion on chromosome 13q was described as being the cause of SCA8. We have now (1) assessed the repeat size in a group of patients with ataxia and a large number of controls, (2) examined the intergenerational transmission of the repeat, and (3) estimated the instability of repeat size in the sperm of one patient and two healthy controls. Normal SCA8 chromosomes showed an apparently trimodal dist

SUBMITTER: Silveira I 

PROVIDER: S-EPMC1288166 | biostudies-literature | 2000 Mar

REPOSITORIES: biostudies-literature