While the lower expression of PrPC in G2 mice may contribute to the longer incubation period observed in this model after challenge with vCJD, the G2 mice are more susceptible to infection with the sCJDMM2- and G2-passaged 263K TSE agents despite expressing lower levels of PrPC than wild-type controls. The gene discussed is PRNP; the disease is variant Creutzfeldt-Jakob disease.