[Bovine spongiform encephalopathy: a review].

Transmissible Spongiform Encephalopathies are a group of chronic, always fatal diseases affecting the central nervous system of humans and animals. They occur in all species and are probably caused by agents called prions. In this minireview, a first part provides an overview of the various disease forms, a second part is devoted to the molecular biology of transmissible spongiform encephalopathies, and a last part deals with the specific problems of the Bovine Spongiform Encephalopathy.