Diseases caused by these agents involve post mortems showing brain tissue with large vacuoles in cerebellum and cortex tissue.  
First identified by Stanley B. Prusiner, these agents cause such diseases as Gertsmann-Sträussler-Scheinker disease, fatal familial insomnia, and kuru. Diseases caused by these agents involve post mortems showing brain tissue with large vacuoles in cerebellum and cortex tissue.  Scrapie in sheep, chronic wasting disease in elk and mule deer and bovine spongiform encephalopathy or mad-cow disease are all caused by these agents.  For ten points, these infectious proteins are the cause of Creutzfeld-Jacob Disease, the human equivalent of mad-cow disease.
First identified by Stanley B. Prusiner, these agents cause such diseases as Gertsmann-Sträussler-Scheinker disease, fatal familial insomnia, and kuru.
{Prions}