PRNP and Creutzfeldt Jacob disease: Intracerebral injection of rat PrP prions into the brains of Tg(PrP) rats led not only to accelerated disease but also to selective propagation of PrP prions in the CNS; this result was similar to findings that showed that Tg mice can propagate human Creutzfeldt–Jakob disease (CJD) prions [73].