PRNP and Creutzfeldt Jacob disease: Although other diagnostic methods such as magnetic resonance imaging (MRI), electroencephalogram (EEG), and genetic testing of the PRNP gene have also been used for CJD diagnosis, the confirmation of PrPSc accumulation in the appendix is highly desirable to diagnose variant CJD in Korea since the PrPSc test on the appendix is a relatively comprehensive diagnostic method compared to brain autopsy.