Home > Encyclopedia of Neurological Disorders > Prion Diseases

Definition

Prion diseases are also called transmissible spongiform encephalopathies (TSEs) because of the sponge-like holes they leave in infected brains. The infectious agents in prion diseases are prions, or proteinaceous infectious particles, that can reproduce themselves. Prions have the ability to transform normal, benign protein molecules into infectious, deadly ones by altering their structure. These deadly proteins initiate a sequence of events in which many benign proteins are transformed into new deadly ones upon contact. Prions are distinct from all other infectious materials in that they do not contain any genetic material. There are multiple prion diseases, including bovine spongiform encephalopathy (BSE), or "mad cow disease." Some prion diseases are hereditary, and involve a mutation in the gene that encodes for the prion...