Using transgenic mice expressing ovine PRNP (ovinized mice), scrapie incubation times were substantially reduced compared with incubation times in wild-type mice (Crozet et al., 2001; Vilotte et al., 2001) while histopathologic profiles and PrPres biochemical features characteristic of scrapie prion types were maintained (Baron et al., 2004; Chong et al., 2015; Cordier et al., 2006). This evidence concerns the gene PRNP and scrapie.