Classical scrapie (subsequently referred to as scrapie) and Bovine Spongiform Encephalopathy (BSE) are transmissible spongiform encephalopathies (TSEs), a group of fatal neurodegenerative disorders of animals and man which are characterised by the deposition of a misfolded isoform (PrPSc or prion) of a cellular protein (PrPC), spongiosis and gliosis. This evidence concerns the gene PRNP and scrapie.