Fore tribe's genetic mutation furthers understanding of brain diseases

June 11, 2015 1:00 PM

How a history of eating human brains protected this tribe from brain disease After years of eating brains, some Fore have developed a genetic resistance to the molecule that causes several fatal brain diseases, including kuru, mad cow disease and some cases of dementia.

See also:
Scientists find CJD resistance gene
Tribe Became Immune to Brain Disease— by Eating Brains (has links to other articles)

posted by Michele in California (25 comments total)

So zombies are actually seeking health food?
posted by jim in austin at 1:26 PM on June 11, 2015 [7 favorites]

This seems like one of those things where the cure is (almost) as bad as the disease.
posted by LeLiLo at 1:36 PM on June 11, 2015 [1 favorite]

I mentioned this last night to a friend I had for dinner.
posted by ZenMasterThis at 1:45 PM on June 11, 2015 [20 favorites]

ONE WEIGHT LOSS SECRET THEY DONT WANT YOU TO KNOW
posted by klangklangston at 1:54 PM on June 11, 2015 [10 favorites]

Yeah, it wasn't that they 'developed' resistance, it's that some happened to have it and those without resistance died.
posted by Segundus at 2:04 PM on June 11, 2015 [3 favorites]

Natural selection at work! I wonder if Charles Pierce has heard about this?
posted by TedW at 2:38 PM on June 11, 2015

"Yeah, it wasn't that they 'developed' resistance, it's that some happened to have it and those without resistance died."

Yeah, that's how developed resistance happens.
posted by I-baLL at 2:42 PM on June 11, 2015 [12 favorites]

Would appear that we're all decedents of zombies. From the article:

In a study published in Science, he found that people as far-flung as Europe and Japan exhibited the genetic protection, indicating that cannibalism was once widespread and that prehistoric humans probably dealt with waves of kuru-like epidemics during our evolution.
posted by kisch mokusch at 3:04 PM on June 11, 2015 [1 favorite]

[muffled hannibal theme playing in the distance]
posted by poffin boffin at 3:10 PM on June 11, 2015 [1 favorite]

Unfortunately, the brain is 60% fat, so the tribe was killed off by massive heart attacks.
posted by a lungful of dragon at 3:14 PM on June 11, 2015 [3 favorites]

William Arens is spinning in his grave!
posted by mittens at 3:26 PM on June 11, 2015

"Unfortunately, the brain is 60% fat, so the tribe was killed off by massive heart attacks."

New Yorker cartoon pitch: Those stereotypical (and kinda racist) Charles Addams cannibals preparing to tuck into a brain in a pith helmet, one telling the other, "Yes, but my doctor says it's the good kind of cholesterol."
posted by klangklangston at 4:05 PM on June 11, 2015 [13 favorites]

Now I have this image of white guys dressed in bark, feathers and berry juice for the class action law suit commerical.
posted by clavdivs at 4:42 PM on June 11, 2015 [2 favorites]

"Yeah, it wasn't that they 'developed' resistance, it's that some happened to have it and those without resistance died."

Yeah, that's how developed resistance happens.

I took Segundus to mean that this tribe happened to have a certain level of this mutation for resistance hanging around (a polymorphism), and that's what allowed them not to be killed off completely when they came up with this brain-eating custom -- which is plausible.

However, unless I am misunderstanding it, a sentence in the abstract of the Nature article seems to suggest something more surprising is going on here:

Indeed, this single amino acid substitution (G--->V) at a residue invariant in vertebrate evolution is as protective as deletion of the protein. [my emphasis]

In other words, this one tribe is the only place in vertebrate evolution where we see this mutation -- everybody and everything else has a V there, and they have a G!

That kind of conservation usually means the V has to be there or something pretty bad happens, and so selection against a substitution is quite strong.

But selection against kuru must have been even stronger, so when that G substitution randomly happened along after the custom of brain eating was established, the G substitution was selected for rather than against -- kind of like sickle-cell trait in areas with endemic malaria.

So in that very limited sense, perhaps they could be said to have 'developed' resistance.
posted by jamjam at 4:42 PM on June 11, 2015 [5 favorites]

So it remains that in general the way to cure any disease is to expose a large population of people to it over a multi-generational period of time, wait for most of them to die and then figure out what's up with the survivors.
posted by GuyZero at 5:00 PM on June 11, 2015 [1 favorite]

BRAAAAAINAMINS
posted by generalist at 6:12 PM on June 11, 2015 [3 favorites]

The kuru disease was previously covered in an FPP, and that was how I first learnt of it. Unfortunately the link to that feature is dead. Here's the archive.org copy. So I'm glad to read more about this.
posted by cendawanita at 6:58 PM on June 11, 2015

They didn't develop a custom of brain eating as much as we got rid of one.
posted by Renoroc at 8:38 PM on June 11, 2015

"we got rid of one."

Speak for yourself, brain-vegan!
posted by I-baLL at 8:52 PM on June 11, 2015 [1 favorite]

bregan
posted by klangklangston at 9:20 PM on June 11, 2015 [2 favorites]

> So in that very limited sense, perhaps they could be said to have 'developed' resistance.

I don't see what's wrong with using the word "developed" here.

If I understand correctly, there there was a random mutation in some subset of the population that provided a selective advantage in the form of resistance to a disease. As a consequence, the mutation became ubiquitous in the population.

How is this different from any other case in which a population acquires resistance to a disease through natural selection? I mean, this is more or less how every trait evolves, right? Do we not normally use the word "developed" for that? If not, when would it be appropriate to say a population "developed" resistance?
posted by a mirror and an encyclopedia at 10:12 PM on June 11, 2015 [2 favorites]

The major problem with this tribe, though, is that whenever a bunch of men get together, nothing gets done. They just stand around telling each other what to do.

That's the trouble when you have a group consisting entirely of Fore men.

(I'll see myself out.)
posted by Zarkonnen at 11:15 PM on June 11, 2015 [7 favorites]

Fun fact: The opposite of this phenomenon was part of the backstory in the survival horror video game Dead Island. The zombie outbreak was caused by some kind of prion disease similar to kuru being spread by a native tribe that practiced cannibalism.
posted by Gelatin at 5:26 AM on June 12, 2015 [1 favorite]

Yeah, it wasn't that they 'developed' resistance, it's that some happened to have it and those without resistance died.

Epigenetic research is basically killing the idea that the only thing that modifies the genome is survival pressure.
posted by effugas at 4:09 PM on June 13, 2015

Would appear that we're all decedents of zombies.

I see what you did there.
posted by mistersquid at 5:26 PM on June 13, 2015 [2 favorites]