There is a great urgency to better understand the manner in which prions (PrPSc) generate and propagate, as BSE (mad cow disease) is currently a major health threat abroad and the rapid spread of CWD throughout the U.S. is a major concern here at home. The BSe outbreak has led to the development of a TSE Advisory group to the FDA, to ensure the safety of the U.S. blood supply. In addition, the spread of CWD HAS Led to the mandatory culling of deer and elk in several states. Thus, understanding the mechanism and determinants of the transmissible capacity of prion disease is of great importance. Inherent within our studies is the potential to find treatment strategies for prion disease. Our spontaneous disease mouse models will provide insight into the genetic prion disease determinants and will eventually prove useful for the testing of potential treatments for prion disease.