In the study presented here, two transgenic mouse lines, used in different laboratories in Europe, that overexpress ovine PrP (ARQ/ARQ) 2–4-fold (TgshpIX) and 4–8-fold (TgshpXI), respectively, were inoculated intracerebrally with BSE, ovineBSE and well-defined isolates of sheep scrapie originating from different host genotypes. Here, PRNP is linked to scrapie.