ATXN8OS and spinocerebellar ataxia type 8: To investigate the broader significance of MBNL1 in SCA8, we tested the effects of Mbnl1 depletion on a behavioral phenotype in our SCA8 mice by crossing heterozygous Mbnl1+/ΔE3 animals with a low-copy SCA8-BAC-EXP5 line.