The theory that has the strongest backing these days started off as quirky notion put forth by British physicist J.S. Griffith thirty years ago. Over the last ten years Stanley Prusiner at the University of California, has transformed that quirky notion into the scientific mainstream. Prusiner's version of how a proteinaceous infectious particle or PRION as he calls them could work, goes something like this.
It turns out that the infectious protein, henceforth to be referred to as "the prion", is a dented version of a normal protein. Its most commonly found tethered to the outside of brain cells.
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