CALB1 and autosomal dominant cerebellar ataxia: Additionally, using immunofluorescence staining of calbindin, a Purkinje cell marker, it was possible to detect a significant loss of calbindin‐positive Purkinje cells in the KI/KI mice at 18 weeks of age (an age close to 5 months) (Figure 2D,E); this mirrors a characteristic feature of SCA, namely the loss of calbindin‐positive Purkinje cells, in both human patients [20] and in other mouse models [2].