Prion diseases, such as Creutzfeldt-Jakob disease (CJD) of humans and bovine spongiform encephalopathy (BSE) of cattle, are transmissible neurodegenerative disorders linked to the accumulation of a misfolded isoform (PrPSc) of the host-encoded glycophosphatidylinositol (GPI)-linked prion protein (PrPC) [1]. This evidence concerns the gene PRNP and Creutzfeldt Jacob disease.