PRNP and Creutzfeldt Jacob disease: CJD subtype can be further defined by different patterns of pathology (i.e. spongiform change and neuronal loss) and PrPSc deposition in the brain [3, 30, 31, 33], and by transmission properties into non-human primates [8] or transgenic mice expressing human PrPC [1, 2, 5, 9, 13, 23, 44].