Science
What is A prion?
A prion is a misfolded protein that can force normal proteins to misfold too, spreading damage through the brain. Prions cause rare, fatal diseases like mad cow disease — and uniquely, they are infectious without any DNA or RNA.
See it, don’t just read it.
Watch a 2-minute lesson with voice + animation that explains a prion.
Key things to understand
- 1It's a normal protein folded into the wrong, harmful shape.
- 2It converts healthy proteins into the same bad shape, like a chain reaction.
- 3Unlike viruses and bacteria, it carries no genetic material.
- 4It causes fatal brain diseases such as mad cow disease and CJD.
- 5Prions are extremely tough, resisting heat and normal disinfection.
Frequently asked questions
- How can a protein be infectious?
- A prion physically templates healthy proteins into its misfolded shape, so damage spreads without any genes — unlike any virus or microbe.
- What diseases do prions cause?
- Fatal brain diseases including mad cow disease (BSE), Creutzfeldt-Jakob disease in humans, and scrapie in sheep.
- Why are prions so hard to destroy?
- Being just sturdy protein, they survive heat, radiation, and disinfectants that easily kill bacteria and viruses.