In contrast, other inocula comprising sporadic CJD and iatrogenic CJD with different PRNP codon 129 status and PrPSc types, and also vCJD and vCJD passaged in 129VV Tg152 mice (which contained type 5 PrPSc[37], [40]) transmitted very poorly or not at all (Table 1). This evidence concerns the gene PRNP and variant Creutzfeldt-Jakob disease.