Did we inherit ADHD from the Neanderthals?

//Did we inherit ADHD from the Neanderthals?

Cro-Magnons wrote the history books

What if our ADHD traits come from Neanderthal genes? Neanderthals were not the brutal violent cavemen as depicted erroneously by Victorians – but were as intelligent, artistic and less aggressive than our predominantly Cro-Magnon ancestors. They were red-haired, fair skinned and were more peaceful. Neanderthals lived in matriarchal small tribes, buried their dead, were artistic and made tools and musical instruments like flutes. Might those of us with ADHD and ADD have inherited Neanderthal genes?

Neanderthals arrived in Europe from Africa around 160,000 years ago and colonised Ice Age Europe. They dominated Europe until Cro-Magnons arrived from Africa, about 45,000 years ago. Over the next seventeen thousand years or so – by 28,000 years ago, all Neanderthals had died out, leaving Cro-Magnons (modern humans) to reign supreme.

The evidence is pretty mixed up on inter-breeding with CroMagnons, but knowing how people so enjoy procreation, it is hard to believe there was none going on as the Cro-Magnons were killing out all the Neanderthals.

Since I wrote the original article in 2009, much has developed in genetics. As of 2016, there is now conclusive genetic evidence of hanky-panky between our ancestors and Neanderthals. From 1-4% of the European genome derives from Neanderthal DNA, see the Neanderthal Genome Project, and watch a great lecture by Prof. Tom Higham: “When Neanderthals and Modern Humans Meet”.

According to Wikipedia, there was interbreeding of modern humans (more accurate term than Cro-Magnon) with Neanderthals, Denisovans, and possibly others. Neanderthal-derived DNA is rare in the genome of Sub-Saharan African people who may have a different genetic contribution from a now-extinct archaic African hominin population. While in Oceanian/Southeast Asian populations, there is more Denisovan derived DNA, up to 6%.

You can get personally tested to see how Neanderthal you are.

Links with addiction

US researchers reviewed 28,000 patients historical medical records and their biological samples. In Science, they describe how they matched the modern human genes in the database against a map of those groups of genes known to have been inherited from Neanderthals. Genes responsible for faster blood clotting and skin adaptations were found, but more importantly for an ADHD link, there is a higher chance of depression and (nicotine) addiction.

“Our main finding is that Neanderthal DNA does influence clinical traits in modern humans”,“We discovered associations between Neanderthal DNA and a wide range of traits, including immunological, dermatological, neurological, psychiatric and reproductive diseases.” –  John Capra, evolutionary geneticist at Vanderbilt University in Nashville.

Could it be that Neanderthals inter-breeding brought to Cro-Magnons some positive, beneficial traits, perhaps some creative, inventive and exploring genes that helped shift Cro-Magnon society and propelled it forward to today’s advanced position?

Is DRD4-7R the answer?

One of the genes of interest, that’s linked to addictions (including smoking) is the DRD4-7R gene, linked with dopamine levels in the brain. This is a mutant-variation of the usual DRD4 gene, the 7R variant is associated with ADHD and with risk-taking, novelty-seeking, intolerance of routine and exploration.

The history of the gene is that it appears in our genome around the time the Neanderthals and Cro-Magnons “got it together”. This restless gene can cause people to explore, a study by Chen in 1999 found the DRD4-7r form of the gene more likely to occur in modern day societies where people migrated longer differences from where we first originated in Africa. These findings suggest that this gene could be the motivation behind the yearning to travel, to move and to see the world.  Since boredom and laziness are the drivers of invention, perhaps this DRD4-7r gene drove mankind to more quickly develop tools, technology and culture.

In the population today, about 10% have the active DRD4 7R gene, risk-taking, creative, innovative and with less desire to follow authority. Society needs only some of the tribe to explore, invent new ways of doing things, break the rules and find new solutions. We only need some to perform and create art, to make us laugh, to write literature and music that can be enjoyed by all. The tribe would fail disastrously if everyone wanted to explore, sing and break the rules.  The bulk of the population needs to be be happy with repetitive non-creative tasks and processes. Fortunately most people prefer farming, teaching, creating rules, running organisations, policing and making things – over risky pursuits like exploring and inventing.

Maybe I’m a Neanderthal

When I first wrote about Neanderthals in 2008, this theory based on a short article here, felt very much a speculative folly. Amazingly the science of genetics is advancing so rapidly that not only has inter-breeding been confirmed but the DRD4-7R gene could be the magic bullet. Plenty of research is underway as we start to really understand the origins of our genetically inherited personalities.

It seems obvious to anyone (beside most ADHD medical specialists), that the neurotransmitters affected by ADHD,  not only cause problems in modern society but equally have benefited and continue to benefit society in many critical ways. The strong desire to explore, set up businesses, entertain, invent, to rebel and to create has brought mankind a long way from those Victorian images of cave dwelling savages.

I’m happy to be part Neanderthal!

2016-12-07T16:32:03+00:00July 1st, 2015|Out of the box|