Neanderthal gene - alcoholism link

[Lucas_Jackson]

A friend tells me there is a study that links a higher Neanderthal DNA percentage to a predisposition to alcoholism. Googling, I find mainly articles about Ozzy.

Is there anything to this or is my friend full of hooey?

[Broomstick]

I think he’s full of hooey.

Ethnic tendencies towards alcoholism tend to be highest among Native Americans, but the group with the highest percentage of Neanderthal DNA is Europeans.

So… no, I don’t think so.

[DSeid]

Not so far off though. Neandertal genes are associated with a variety of positive and negative traits, predispositions to diseases, and with nicotine addicition, but apparently not so far with alcoholism.

@Science

Akey and Capra joined forces and searched for more than 6000 Neandertal haplotypes in genetic data from 28,416 adults of European ancestry. After pinpointing chunks of DNA inherited from Neandertals, the team used statistical analysis to link possession of these archaic variants to a higher risk of the diseases or other traits captured in the billing data, Capra says.

The search netted a dozen Neandertal genes likely to cause significant risk of disease today. For example, one gene variant apparently makes blood more sticky and prone to coagulate. This fast clotting may have spelled the difference between life and death when Neandertals hunted dangerous animals or hemorrhaged after birthing big-brained babies. But it can also increase the risk of blood clots and strokes, which would have been much less common in prehistoric times when most people died young.

The researchers also found a number of Neandertal genes associated with neurological conditions, including depression, which can be triggered by disturbed circadian rhythms. Other variants were linked to precancerous skin lesions called actinic keratoses. Capra speculates that Neandertal brain chemistry and their skin responses to sunlight may both have been attuned to the light conditions and lifestyles of prehistoric Europe. The gene variants responsible may be maladaptive now that most people live by artificial light.

Other Neandertal alleles regulate the transport of thiamine, or vitamin B1, which metabolizes carbohydrates in cells of the gut. Neandertal diets, rich in meat and nuts, may have provided ample thiamine, but people munching processed foods today may not get enough, and having the Neandertal variant may predispose them to malnutrition, Capra speculates.

The study also revealed Neandertal genes associated with incontinence, bladder pain, and urinary tract disorders. And a single base change was associated with nicotine addiction, making it the second Neandertal allele found so far to boost the risk of tobacco addiction.

The Neandertal health legacy isn’t entirely negative. Two studies published in The American Journal of Human Genetics last month identified three archaic genes that boost the innate immune response, which helps defend against fungi and parasites as well as bacteria. All three have been strongly selected for in Europeans and Asians, says computational biologist Janet Kelso of Max Planck, lead author of one study. The three genes work together in subtle ways to regulate the expression of toll-like receptors on the surface of white blood cells, presumably boosting the innate response, says Lluis Quintana-Murci, a population geneticist at the Pasteur Institute and the French National Center for Scientific Research in Paris, lead author of the other study.

[Squink]

I get the impression that lately Homo Sap has taken to trying to dump many of our less admirable traits off on our poor defunct predecessors.
We’ll probably hear soon that the hobbit people of Indonesia were skilled thieves.

[DSeid]

There is lots of presumption that Neanderthal genes preserved had been, back 10,000 years ago or so, beneficial to H sapiens moving into the neighborhood, and that many are still beneficial today. Certain areas of the genome have more Neanderthal genes and others are very empty of them. The presumption is that the areas that are fairly absent were mainly genes that were of negative genetic fitness impact and the ones more concentrated with them were for genes that were of positive genetic fitness impact. But proving what those unknown positive impacts were or are is hard to do. OTOH finding an association, even a fairly weak one, with reported negative impacts in a solid database, not as difficult. Even some of the negative impacts may be due to traits that were positive back 10,000 years ago but which have different impacts in a different world (Nicotine addiction? The gene(s) involved HAD to do something positive once upon a time.)