The ADHD Advantage: Did the “Hyper” Gene Benefit Our Nomadic Ancestors?

ADHA has gotten a bad rap in the 21st century, but all of us fidgety hyper-hypos may have evolved this way for good reason, say scientists. An ADHD-associated version of the human gene DRD4 was found to be linked to superior health among nomadic tribesmen. But oddly enough, it seems to be linked with malnourishment among their more settled cousins. Here is my completely unscientific explanation for why that might be the case: People who can’t sit still would be appreciated in a society that is always on the move, whereas in a sedentary population—like most of us live in today—we’re all but an unwanted annoyance. But whatever the real reason, scientists say these findings offer clues to why some of us evolved the way we did, and what that means for the future.

A research team led by anthropologist Ben Campbell of the University of Wisconsin-Milwaukee along with colleagues from Northwestern University, Boston University and UNLV particular ADHD gene, found that this particular ADHD gene has completely different effects depending on your environment. The DRD4 gene helps regulate a receptor for dopamine, one of the chemical messengers used in the brain. But people can have different versions of the gene.

Previous research has linked the gene with Attention Deficit Hyperactivity Disorder-type behavior in young men – risk-taking, reward-seeking and impulsivity, says Campbell. Another variation, called the 7R allele, is associated with novelty-seeking in addition to ADHD.

The researchers conducted the study among the Ariaal population in northern Kenya – some of whom still live as nomads, while others have recently settled. The research team analyzed the body mass index (BMI) and height of the two groups, nomadic and non-nomadic Ariaal men, who had the variant gene.

They found that those with the 7R allele in the nomadic population were better nourished than their non-nomadic brethren who carried 7R allele.

Campbell says these results underscore the complexity of genotype on the expression of behavior. Different environments can determine whether behaviors associated with the gene, such as ADHD, are more or less effective.

"We may have difficulty understanding ADHD in part because we are considering the behaviors associated with it in only one environment – the present one," he says. "The thinking used to be one gene, one outcome. Now we know that one gene with different environments yields different outcomes."

Campbell says that a gene that is beneficial in one setting, can be detrimental in another.

"This suggests that this particular allele may be beneficial in a traditional setting with high levels of habitual physical activity, but carries with it longer term costs in a more sedentary setting."

So, in other words, all of us with ADHD need to head back to the desert with a pack of camels loaded up with tents to really make the most of our “disorder” (how dare they call it that when it turns out it’s an evolutionary advantage unless you’re a semi-comatose couch potatoes). Of course half of us will absent-mindedly forget to bring essentials—like water—but we’ll have a lot of fun. Who’s with me?

Posted by Rebecca Sato

Related Galaxy posts:

“Hyper-Speed” Evolution Discovered

Source Link:

Comments

[RJ]

I would argue that in todays mobile and constantly changing world, CEOs with ADHD have a marked advantage. Its never held me back. I have no problem accepting change and thriving in a fast-paced environment, in fact I've always felt like my ADHD helps, so if its a "disorder" then its one I'm glad to have.

Another thing that a lot of people don't realize is the the flip side of not being able to concentrate on any one thing for long, is that if its something we're very interested in--many ADHD carriers are able to hyper focus to a degree that non-ADHD carriers don't seem to be capable of. Obviously our genes are like everything else in life--they involve trade-offs. Every asset has its liability and vice versa.

[Will Anjos]

This isn't a new idea, Thom Hartmann proposed a "Hunter vs Farmer" thory of ADHD back in 1978. He published "ADD: A Different Perception" in 1992. At least it now appears to have some scientific validity.

See http://en.wikipedia.org/wiki/Hunter_vs._farmer_theory for mor info.