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Summary

Occurring in approximately 1 per 1,000,000 people yearly worldwide, Creutzfeldt–Jakob disease (CJD) is the most common form of prion disease. Prion diseases are a group of neurodegenerative disorders that results from the abnormal accumulation of a cell surface glycoprotein called prion protein (PrP), which is encoded by the prion gene PRNP on chromosome 20. Interestingly, PrP is normally found in healthy brains; however, for an unknown reason, and by an unknown mechanism, normal PrP undergoes a posttranslational conformational change that makes it insoluble and resistant to protease degradation. These abnormal forms of PrP then self-propagate and convert normal forms of PrP to pathological forms like themselves. Though there are no known environmental or modifiable risk factors currently known for CJD, there is a genetic risk factor, which is homozygosity of the codon 129 on PRNP gene. Although 90% of CJD is sporadic, there are also familial and iatrogenic forms.