This reduction in the severity of ataxia was associated with reductions in Purkinje cell damage, leptomeningeal leukocyte infiltration (Fig. 11a), white matter demyelination (Fig. 11a, b, d), neurodegeneration (FJC staining Fig. 11c) and gliosis (IBA1 and GFAP expression, Fig. 11d). This evidence concerns the gene AIF1 and cerebellar ataxia.