PRNP and sporadic Creutzfeldt-Jakob disease: Thus far, more than 50 mutations in PRNP have been reported to cause autosomal dominant inherited CJD, and a large number of polymorphisms in PRNP (including codon 129, 219, 178, 200, and 232, etc.)have been identified as susceptible factors in sporadic CJD (sCJD) cases.