Although they are known to become activated in the early stages of Creutzfeldt-Jakob disease, the functional relationships between microglia and PrPc remain unclear; however, the activation of these cells is accompanied by a downregulation of the expression of the PRNP gene and it also appears that, during infection or in degenerative CNS disorders, this could promote the conversion of PrPc into PrPSc [8]. Here, PRNP is linked to Creutzfeldt Jacob disease.