Prions Essay

1124 Words May 16th, 2005 5 Pages
Sometimes a scientific discovery shakes the confidence of scientists, making them question whether they truly understand nature's ground rules. That's exactly what prions have done to scientists' understanding of the ground rules for infectiousdiseases. Prions cause diseases,but they aren't viruses or bacteria or fungi or parasites. They are simply proteins, and proteins were never thought to be infectious on their own. Organisms are infectious, proteins are not. Or, at least, they never used to be. Prions entered the public's consciousness during the mad cow epidemic that hitEngland in 1986. For decades, however, scientists had searched for unusual, atypical infectious agents that they suspected caused some puzzling …show more content…
Sheep and goats with the disease scrapie, which is like mad cow disease, become so uncomfortable and itchy that they frantically rub up against anything they can, finally scraping off – hence, the name of the disease -most of their wool and hair. Ultimately, infected prion-bloated brain cells die and release prions into the tissue. These prions then enter, infect, and destroy other brain cells. And, as clusters of cells die, the brain stops looking like a brain and starts looking more like Swiss cheese. The medical term for the prion diseases is "spongiform encephalopathies," in acknowledgement that the sick brains are riddled with holes and have taken the form of sponges. Shepherds and farmers whose sheep had scrapie never seemed to get scrapie themselves. So, for a long time, scientists assumed that the prions of animals did not cause infections in humans. But, between 1994 and 1996, 12 people in
England came down with Creutzfeld-Jakob disease (CJD), a human prion disease whose symptoms are not unlike those of the mad cows, and all the victims had eaten beef from cows suspected of having mad cow disease. In October, 1996, scientists in England reported that the prions from ten of the British patients were remarkably like those of the mad cows and not like those of people