PRNP and sporadic Creutzfeldt-Jakob disease: We report a detailed study of a cohort of sporadic Creutzfeldt-Jakob disease (sCJD) VV1–2 type-mixed cases (valine homozygosity at codon 129 of the prion protein, PrP, gene harboring disease-related PrP, PrPD, types 1 and 2).