Further, ribonuclear ATXN8OS foci were found to be co-localized with MBNL1 and displayed an alternative splicing pattern in both SCA8 mice and SCA8 patients (Daughters et al., 2009), demonstrating a gain-of-function role for expanded CUG ATXN8OS RNA in the pathogenesis of SCA8. The gene discussed is MBNL1; the disease is spinocerebellar ataxia type 8.