For conditional SCA1[82Q] mice, 6 weeks with the gene on revealed a detectable degree of Purkinje cell dendritic atrophy that became more severe by 12 weeks (A, B). However, in 6 weeks gene-on/6 weeks gene-off animals, cal bind in immunostaining showed essentially normal Purkinje cells, comparable with 12-week-old wild-type mice (C, D). See the article by Zu et al. for details.