Ocular changes in patients with spinocerebellar degeneration and repeated trinucleotide expansion of spinocerebellar ataxia type 1 gene
T. Abe, K. Abe, M. Aoki, Y. Itoyama and M. Tamai
Department of Ophthalmology, Tohoku University School of Medicine, Sendai, Japan.
OBJECTIVE: To examine ocular changes in patients with spinocerebellar
degeneration who have repeated trinucleotide expansion in the
spinocerebellar ataxia type 1 (SCA1) gene. DESIGN: Ophthalmic findings in 6
patients from 3 families whose DNA analysis revealed that they had an
expanded allele of the trinucleotide repeated in the SCA1 gene were
compared with those of normal control subjects and other healthy family
members. The DNA was extracted from peripheral blood lymphocytes of the
neurodegenerative family and normal control subjects. SETTING: University
medical center. RESULTS: Visual acuity gradually decreased in successive
follow-up visits. Color vision and visual fields were gradually affected.
Electroretinograms showed mild attenuation of oscillatory potentials.
Corneal endothelial cell density was severely decreased from 600 to 1300
cells/mm2. These findings were not observed in the normal control subjects,
other healthy family members, or other patients with spinocerebellar
degeneration who had repeated trinucleotide expansion of other genes.
CONCLUSION: To the best of our knowledge, this is the first report
describing the association between ocular changes in patients with
spinocerebellar degeneration and gene mutation. These ocular changes were
considered specific to patients who had the expanded allele of the repeated
trinucleotide in the SCA1 gene.
