Final answer:
TSEs such as Creutzfeldt-Jakob disease are caused by abnormal prion proteins. The strain specificity of TSEs refers to the ability of different strains of prion to cause different symptoms and diseases. This is believed to be determined by variations in the conformation of the prion protein.
Step-by-step explanation:
Transmissible spongiform encephalopathies (TSEs) such as Creutzfeldt-Jakob disease are caused by abnormal versions of a protein called prion. The strain specificity of TSEs refers to the ability of different strains of prion to cause different symptoms and diseases. This strain specificity is believed to be determined by variations in the conformation of the prion protein, which affect its ability to interact with other proteins and cells in the body. For example, different prion strains may have different affinities for specific cell types or may cause different patterns of protein aggregation in the brain.