Indeed, bank voles and mice have a different susceptibility to prions and rather opposite prion strain preferences (65, 67, 70), whereas the genotype at codon 129 of human PrPC is known to be critical for the risk of acquired and sporadic prion diseases as well as in the phenotype modification of prion diseases (85, 86, 87, 88). Here, PRNP is linked to prion disease.