Prion disease is typically characterised by histological features of spongiform vacuolation, neuronal loss and astrocyte proliferation (Budka, 2003), along with deposition of PrP aggregates in the brain and a strong microglia response, which can be identified upon brain biopsy in patients, or on post-mortem histopathological analysis of the brain in patients and animals (Wenborn et al., 2015). This evidence concerns the gene PRNP and prion disease.