PRNP and Creutzfeldt Jacob disease: The heating step significantly increased the detection of PrP in the spinal cord samples from c-BSE- (H/U ratio = 6.3 ± 6.2; range 1.8–28.0) and v-CJD-infected animals (H/U ratio = 5.4 ± 2.4; range 1.9–11.2), in comparison to healthy (H/U ratio = 2.0 ± 1.0; range 0.9–3.6) and myelopathic (H/U ratio = 1.8 ± 1.0; range 0.7–3.5) primates, for which the effect of heating was less marked.