Finding out what makes a prion protein go bad may help control these brain-eating pathogens.

Prions are believed to be the cause of an array of rare but horrifying neurological diseases, such as Variant Creutzfeldt-Jakob disease (known, in cattle, as mad cow disease).

These misfolded proteins essentially eat microscopic moth holes into the brain. They are untreatable and always fatal.

Researchers at Imperial College London and the University of Zurich have now identified a critical step in the misfolding that creates a prion.

They were also able to halt the process, in a Petri dish, using antibodies — paving the way to possible treatments.

“Prion diseases are aggressive and devastating, and currently there is no cure,” Imperial’s Alfonso De Simone, the study’s lead researcher, said in a release.

“Discovering the mechanism by which prions become pathogenic is a crucial step in one day tackling these diseases, as it allows us to search for new drugs. Now we know what we’re targeting, we know what features drugs need to have to stop prions becoming pathogenic.”