Short answers, pulled from the story.
A prion is a misfolded form of the naturally occurring prion protein (PrP) that induces other normal proteins of the same type to misfold, triggering a chain reaction that leads to cellular death. Prions cause neurodegenerative disease by aggregating in the central nervous system to form amyloid plaques, producing a spongy, hole-filled brain tissue. All known prion diseases are fatal and have no effective treatment.
Stanley B. Prusiner coined the word "prion" in 1982. It is short for "proteinaceous infectious particle", derived from the words protein and infection. Prusiner, based at the University of California, San Francisco, was awarded the Nobel Prize in Physiology or Medicine in 1997 for his research into prions.
Prions cause several fatal human diseases, including Creutzfeldt-Jakob disease in sporadic, familial, iatrogenic, and variant forms, Gerstmann-Straussler-Scheinker syndrome, fatal insomnia, kuru, and familial spongiform encephalopathy. The incubation period ranges from 5 to 20 years or more, but once symptoms appear the disease progresses rapidly to brain damage and death.
Prions are resistant to proteases, heat, ionizing radiation, and formaldehyde, making standard sterilization insufficient. The World Health Organization recommends specific protocols involving sodium hydroxide or sodium hypochlorite combined with autoclaving at 121 degrees Celsius. Heating at 134 degrees Celsius for 18 minutes in a pressurized steam autoclave has been found to be somewhat effective.
A polymorphism at codon 129 in the PRNP gene significantly affects susceptibility to sporadic Creutzfeldt-Jakob disease. Individuals with a homozygous methionine/methionine genotype at that position are approximately five times more likely to develop sporadic CJD than those with a heterozygous methionine/valine genotype.
Prion-like mechanisms are implicated in both Alzheimer's disease and Parkinson's disease, though neither is classified as a prion disease. Misfolded proteins including Abeta, tau, TDP-43, and alpha-synuclein spread through the brain by self-templating in a manner similar to prions. In 2015, a prion form of alpha-synuclein was specifically linked to multiple system atrophy, and over 250 human proteins are predicted to contain prion-like domains.