Preliminary analysis based on the oldest age cohort (the mice euthanized at 32 weeks of age; 8 animals per group) identified the molecular layer of the cerebellum (its relative volume per granular layer volume [Cb-ML]) and two regions of the hippocampus (the dentate gyrus molecular layer [DG-ML] and the inner layers of the Cornu ammonis [stratum radiatum + lacunosum-moleculare; CA-SRLM]) as those regions of the brain most sensitive to volumetric atrophy in the SCA1 mice (Fig. 4a, Suppl. The gene discussed is ATXN1; the disease is Atrophy.