Trinucleotide expansions in the SCA7 gene in a large family with spinocerebellar ataxia and craniocervical dystonia

Neurosci Lett. 2008 Mar 28;434(2):230-3. doi: 10.1016/j.neulet.2008.01.077. Epub 2008 Feb 13.

Abstract

Spinocerebellar ataxia type 7 is a rare autosomal dominant cerebellar ataxia (ADCA). Herein, we describe the molecular and clinical findings in patients within six generations of a large Chinese family with spinocerebellar ataxia. To identify the genetic cause(s), 4 affected patients and 26 asymptomatic relatives were recruited for the study. Molecular screening of the SCA1 and SCA7 genes was carried out by subcloning and direct PCR-sequencing methods. Both neurological and ophthalmic examinations were performed to investigate the clinical characteristics of the disease. The patients had typical cerebellar ataxia, achromatopsia and macular degeneration, and displayed a rare phenotype manifesting as a combination of cerebellar ataxia and craniocervical dystonia. Mutational analysis of the SCA7 genes demonstrated expanded CAG-repeats in the four patients. In conclusion, we identified expanded CAG-repeats in the SCA7 gene within members of a large Chinese family with spinocerebellar ataxia. The defined phenotypic characteristics of the patients may be helpful for clinical diagnosis and genetic typing of new patients.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Asian People / genetics*
  • Ataxin-7
  • Cervical Vertebrae
  • Dystonia / ethnology
  • Dystonia / genetics*
  • Dystonia / pathology
  • Family Health
  • Female
  • Genetic Testing
  • Humans
  • Magnetic Resonance Imaging
  • Male
  • Nerve Tissue Proteins / genetics*
  • Pedigree
  • Phenotype
  • Point Mutation
  • Spinocerebellar Ataxias / ethnology
  • Spinocerebellar Ataxias / genetics*
  • Spinocerebellar Ataxias / pathology
  • Trinucleotide Repeat Expansion*

Substances

  • ATXN7 protein, human
  • Ataxin-7
  • Nerve Tissue Proteins