Practice that once caused illness and death now provides immunity to some brain diseases.
A once isolated New Guinea tribe, the Fore, would traditionally consume their dead’s cadavers, including their brains. The men would eat the flesh, while the women and children would consume the brain. The ritual led to problems for the Fore people, since their consumption of a certain molecule living in the human brain caused a terrible degenerative illness named “kuru,” which is known to have killed around 2% of the tribe’s population each year. The practice of feasting on cadavers was outlawed in the ‘50s. Now, a new study shows that there was an upside to the Fore’s consumption of human brains.
Gene that protects from brain disease found in study.
In a study published in the journal Nature on Wednesday, one protective gene is written about as guarding people from prions. Prions are a weird, sometimes lethal type of protein that, though made by the bodies of all mammals, can be deformed in such a way that they turn on the bodies that produced them. Deformed prions can even infect surrounding prions, reshaping them, and thus filling the victim’s brains with tiny holes. These holes end up giving the brain a sponge-like texture and historically have caused massive outbreaks of mad cow disease in cattle. These prions are directly linked to a weird kind of deadly insomnia that starves a person of sleep until he or she is dead, as well Creutzfeldt-Jakob Disease, which leads to accelerated dementia, memory loss, and eventual loss of speech and ability to move. The gene identified in this study protects the body against prion-related diseases in an interesting way. A tiny alteration in the genome of Fore people kept prion-making proteins from making the disease-causing type of the molecule, which kept them from getting the Kuru illness. Scientists now believe that the changing of prion molecules’ shapes by other prions is likely responsible for the effects of many degenerative brain diseases, such as Alzheimer’s, Parkinson’s, and dementia.
Incurable prion illnesses have two causes.
Diseases caused by prions have two causes. One is genetic, where the brain disease is passed down from a person’s parents. The other, which accounts for a smaller percentage of cases, is from consumption of infected tissue. Infected tissue can be eaten accidentally in the form of beef from an infected cow.
