III.

Controversy

Prusiner’s revolutionary idea has met with great resistance because DNA and RNA are the only substances now known to replicate in body tissues. The concept of a proteinaceous infectious particle capsized the widely accepted convictions about agents of infectious disease.

Prusiner received the 1997 Nobel Prize in physiology or medicine for his work with prions. Even so, his theory that prions alone produce TSEs remains controversial. Some scientists believe that TSEs are caused by an as yet unidentified slow-acting virus. Some believe that a small virus accompanies a prion, and both are needed to produce scrapie, BSE, and other TSEs. Still other scientists think that other proteins, called “chaperones,” initiate the improper folding of the normal proteins.