sup] The expansion of polymorphic CTG repeats in the SCA8 gene was 107.
sup] Genetic testing demonstrated that the trinucleotide repeat sequences of SCA1, SCA2, SCA3/MJD, SCA6, SCA7, SCA8, SCAl2, SCAl7 and DRPLA were normal.
In our research, we performed a systematic study on 10 Chinese families with SCAs, among which 1 family was identified as SCA1, 6 families were SCA3/MJD, 1 family was SCA7, 1 family was SCA8 and 1 family was undefined.
The SCA8 gene, which is located at 13q21, carries normal CTA/CTG repetitions of 16-37 in the noncoding region; however, approximately 1% of healthy persons exhibit over 100 CTA/CTG repeats.
In our study, the genetic testing of Family J, which presented clinically diagnosed SCA, was not in agreement with the known subtypes of SCA1, SCA2, SCA3/MJD, SCA6, SCA7, SCA8, SCA12, SCA17 and DRPLA.
sup], SCA8 is usually characterized on MRI by different degrees of cerebellar atrophy without significant changes in any other brain region.