Prion Disease

The causative agent in prion disease is a misfolded protein that causes normally folded protein to misfold and aggregate. This aggregate of proteins leads to brain cell damage and death, although the exact mechanism is not known. This makes prion disease the only known type of infectious agent in which the causative agent is not based in genetic information in either the form of DNA or RNA. One of the commonly known examples of prion disease is Mad-Cow disease, and though there are different types for different species, in humans it is known as CJD. Prions cause whole areas of brain cells to die, which gives the brain the appearance of a sponge and therefore a “spongiform” phenotype.

The term prion, also known as PrP, comes from the combination of the term “proteinaceous infectious only”. It is especially hard to prevent prion disease by any sterilization means because most sterilization techniques are targeted towards DNA and RNA, such as chemical reagents or by heating. This leads to the most common way of contracting the misfolded protein. Although it can spontaneously misfold on its own, the prion is often inducted into a system and then causes other proteins to transform and collect together.