Mutations in the prion protein gene (PRNP) cause the inherited prion diseases [21,22] and coding polymorphisms in the prion protein (PrP) are associated with susceptibility to acquired and sporadic Creutzfeldt-Jakob disease (CJD), kuru and influence age of onset in some inherited prion diseases [23-25]. Here, PRNP is linked to Creutzfeldt Jacob disease.