Prion diseases such as scrapie of sheep and goats, BSE of cattle and CJD of humans are transmissible neurodegenerative diseases. The research of our prion group is concerned with providing knowledge to try and answer some of the important questions related to aspects of prion disease pathogenesis, diagnosis and therapeutic strategy. These questions include defining the nature of the infectious agent, determining the molecular basis of prion strain diversity, understanding the mechanism of protein misfolding as PrPC converts into PrPSc, and identification of molecular targets for diagnostic and potential therapeutic interventions. These aspects of PrP biology are being pursued in our attempts to identify and quantify abnormal PrP in the blood of individuals with pre-clinical prion disease. These studies underpin our efforts to develop an effective ante-mortem blood test for prion disease.