To reevaluate this possibility and to analyze in detail the transmission properties of vCJD prions to transgenic animals carrying distinct codon 129 genotype, we performed intracerebral inoculation of vCJD prions to humanized knock-in mice carrying all possible codon 129 genotypes (129M/M, 129M/V, or 129V/V).
So far, all clinical cases of new variant Creutzfeldt-Jakob disease (vCJD), thought to result from the Bovine Spongiform Encephalopathy (BSE) prion agent, have shown Methionine-Methionine (M/M) homozygosity at the M129V polymorphism of the PRNP gene.
Surprisingly, we succeeded in the transmission of vCJD prions to humanized knock-in mice not only with codon 129 Met/Met but also with codon 129 Met/Val.