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Angela
04-05-15, 14:38
I found this study on Dienekes:

http://www.dienekes.blogspot.com/2015/05/eye-color-and-alcohol-dependence.html

This is the link to the study itself:
http://onlinelibrary.wiley.com/doi/10.1002/ajmg.b.32316/abstract

I'm always a bit skeptical about these kinds of studies, but for what it's worth:

"In archival samples of European-ancestry subjects, light-eyed individuals have been found to consume more alcohol than dark-eyed individuals. No published population-based studies have directly tested the association between alcohol dependence (AD) and eye color. We hypothesized that light-eyed individuals have a higher prevalence of AD than dark-eyed individuals. A mixture model was used to select a homogeneous sample of 1,263 European-Americans and control for population stratification. After quality control, we conducted an association study using logistic regression, adjusting for confounders (age, sex, and genetic ancestry). We found evidence of association between AD and blue eye color (P =  0.0005 and odds ratio = 1.83 (1.31–2.57)), supporting light eye color as a risk factor relative to brown eye color. Network-based analyses revealed a statistically significant (P = 0.02) number of genetic interactions between eye color genes and AD-associated genes. We found evidence of linkage disequilibrium between an AD-associated GABA receptor gene cluster, GABRB3/GABRG3, and eye color genes, OCA2/HERC2, as well as between AD-associated GRM5 and pigmentation-associated TYR. Our population-phenotype, network, and linkage disequilibrium analyses support association between blue eye color and AD. Although we controlled for stratification we cannot exclude underlying occult stratification as a contributor to this observation. Although replication is needed, our findings suggest that eye pigmentation information may be useful in research on AD. Further characterization of this association may unravel new AD etiological factors. © 2015 Wiley Periodicals, Inc."

LeBrok
04-05-15, 17:45
It makes sense as both AD and lighter eye colour goes up statistically with upper latitudes in Europe. I linked it some time ago with Hunter Gatherer ancestry, especially ANE (the last Euro Asiatic HGs). ANE also goes up with latitude in Europe, specifically rises towards NE. It's just happened, fairly recently that ANE ancestry persisted the longest in this region, and also blond mutations settled in region around Baltic Sea. This also gives correlation between light eye and ANE ancestry in Europe, however the true causation is ANE genes making people drink more. ANE folks were introduced to alcohol the latest of all European admixtures, therefore they didn't develop proper mutations to deal with AD. By this way of thinking I'm guessing that EEF folks are the ones who can deal with alcohol the best, fewer binge drinking, moderation, fewer addictions and faster alcohol metabolism. Now this would collerate with brown eyes and southern latitude in Europe.

Fire Haired14
04-05-15, 23:35
People with big noses are more prone to stupidity.

Templar
05-05-15, 01:17
It makes sense as both AD and lighter eye colour goes up statistically with upper latitudes in Europe. I linked it some time ago with Hunter Gatherer ancestry, especially ANE (the last Euro Asiatic HGs). ANE also goes up with latitude in Europe, specifically rises towards NE. It's just happened, fairly recently that ANE ancestry persisted the longest in this region, and also blond mutations settled in region around Baltic Sea. This also gives correlation between light eye and ANE ancestry in Europe, however the true causation is ANE genes making people drink more. ANE folks were introduced to alcohol the latest of all European admixtures, therefore they didn't develop proper mutations to deal with AD. By this way of thinking I'm guessing that EEF folks are the ones who can deal with alcohol the best, fewer binge drinking, moderation, fewer addictions and faster alcohol metabolism. Now this would collerate with brown eyes and southern latitude in Europe.

I get what you are saying, but how do you know it is more connected to ANE than WHG? I'd guess they were equally unadapted to consuming alcohol.

LeBrok
05-05-15, 01:26
I get what you are saying, but how do you know it is more connected to ANE than WHG? I'd guess they were equally unadapted to consuming alcohol.
It is also related to WHG, but in lesser degree. WHG were "domesticated" much sooner than ANE. The purer hunter gatherer the more AD.

Fire Haired14
05-05-15, 06:41
Eye color was not directly passed down to the present day without frequencies going in all directions in differnt time periods. We can see in the Haak data eye color frequencies had more to do with geography and time period than genetics(besides WHG). So, associating a trait that is associated with an eye color to an ancient group might not work.

Angela
05-05-15, 06:51
People with big noses are more prone to stupidity.

That was unnecessary and not very helpful.

LeBrok
05-05-15, 07:02
Eye color was not directly passed down to the present day without frequencies going in all directions in differnt time periods. We can see in the Haak data eye color frequencies had more to do with geography and time period than genetics(besides WHG). So, associating a trait that is associated with an eye color to an ancient group might not work.
Alcohol dependency, the lactose persistence and blondism are actually great examples of good mutations, the positive traits, popping up spontaneously and taking hold in places where mostly needed. Alcohol "fighting" genes were only needed in societies able to produce alcohol and lot of it, the farmers. The lowest AD is around Mediterranean Sea, the hub of farmers. The biggest in hunter gatherers.
White/blond traits popped up around Eurasia, but finely they found the best place to persist around Baltic and North Sea. A simple map of solar irradiation tells us why.
Lactose persistent gene in Europe took hold in places where grass is always green and crops sometimes fail.

Angela
05-05-15, 07:24
I don't think that there's any doubt that there's a cline in Europe with less alcoholism in the southern parts of Europe and more in the north. The statistics are clear....anyone can look it up.

They're not saying that blue eyes cause the greater tendency to AD. They're saying there's a correlation. I think the correlation has to do with that south/north cline, because light eyes are also on that cline, with higher percentages as you go north.

Dietary changes as the result of the transition to agriculture meant selection for certain alleles relating to triglyceride levels, as Mathiesen et al made clear.
See: http://biorxiv.org/content/biorxiv/early/2015/03/13/016477.full.pdf

I think there was also selection for specific genes that produce "aversion" from imbibing alcohol beyond a certain limit. I certainly have it, inherited from my mother. It doesn't mean that culture doesn't have a role to play...being drunk and incapable in front of people was an "infamia" when I was growing up, shameful, infamous, especially, God forbid, women. However, did the culture stem in part from the genetics? I don't know.

This paper also discusses the correlation between certain alleles and "protection" against AD:
http://pubs.niaaa.nih.gov/publications/arh301/5-13.pdf

They use Jews as an example of a population with high numbers of these protective genes, (East Asians are another group) and it hardly needs to be said that they are a supremely "Mediterranean" and EEF population.

""The presence of even a single ADH2*2 allele is strongly protective against alcohol dependence."

As to blue eyes, we should keep in mind that according to Mathiesen again, there has actually been selection against blue eyes in southern Europe.

LeBrok
05-05-15, 08:12
I think there was also selection for specific genes that produce "aversion" from imbibing alcohol beyond a certain limit. I certainly have it, inherited from my mother. It doesn't mean that culture doesn't have a role to play...being drunk and incapable in front of people was an "infamia" when I was growing up, shameful, infamous, especially, God forbid, women. However, did the culture stem in part from the genetics? I don't know.

I'm sure it is a big part. An interesting example is how African-Americans "adopted" Christianity. It was easier for them to change their faith than to stop dancing in a holy place, which is not an attractive proposition for any European christian. Black people dance and sing at every occasion and that includes churches. Europeans gave them Christianity but never managed to teach them a proper European etiquette of European Church.

Without genetic predispositions there wouldn't be any singing, dancing, fashion, love stories, and many more things in our cultures, in general sense. The differences between cultures have genetic factor too, but it will be very difficult to separate nurture from nature, when differences are not pronounced much.

Templar
05-05-15, 13:26
It is also related to WHG, but in lesser degree. WHG were "domesticated" much sooner than ANE. The purer hunter gatherer the more AD.

Most ANE in Europe came with the Indoeuropeans though, and they were already mixed with middle eastern farmers (like 30-40%). I think there were parts of Northern Europe that didn't receive any farmer blood until they were conquered by indoeuropeans.

LeBrok
06-05-15, 01:45
Most ANE in Europe came with the Indoeuropeans though, and they were already mixed with middle eastern farmers (like 30-40%). I think there were parts of Northern Europe that didn't receive any farmer blood until they were conquered by indoeuropeans.
Perhaps Finland, Balts and NE Russia were the last places farmers visited. Although there were Neolithic villages in Sweden. On other hand WHG (at least some of them) started mixing with ENF in early Neolithic in Balkans.

Fire Haired14
06-05-15, 04:32
Alcohol dependency, the lactose persistence and blondism are actually great examples of good mutations, the positive traits, popping up spontaneously and taking hold in places where mostly needed. Alcohol "fighting" genes were only needed in societies able to produce alcohol and lot of it, the farmers. The lowest AD is around Mediterranean Sea, the hub of farmers. The biggest in hunter gatherers.
White/blond traits popped up around Eurasia, but finely they found the best place to persist around Baltic and North Sea. A simple map of solar irradiation tells us why.
Lactose persistent gene in Europe took hold in places where grass is always green and crops sometimes fail.

I've never meet a Native American and only seen a few, but from what I hear they're some of the most alcoholic people in the world. My dad used to know alot of Native Americans when he was younger and he said they were consistent with the stero-type. I've heard the same is true for natives in Canada and Alaska.

They were introduced to Alcohol by Europeans only a few hundred years ago. So, I guess according to your theory their alcoholism is consistent with them being less adapted to people groups who have had alcohol for thousands of years. But of course other factors play in too.

LeBrok
06-05-15, 06:27
I've never meet a Native American and only seen a few, but from what I hear they're some of the most alcoholic people in the world. My dad used to know alot of Native Americans when he was younger and he said they were consistent with the stero-type. I've heard the same is true for natives in Canada and Alaska.

They were introduced to Alcohol by Europeans only a few hundred years ago. So, I guess according to your theory their alcoholism is consistent with them being less adapted to people groups who have had alcohol for thousands of years.
Same problem are facing Australian Aboriginies, the pure hunter gatherers, and also on lesser scale SS Africans and African Americans, who have a very strong admixture of hunter gatherers.



But of course other factors play in too. Sure, take away alcohol and you don't have AD problem. Otherwise with genetics, either you have it or you don't.

arvistro
06-05-15, 07:37
http://gamapserver.who.int/gho/interactive_charts/substance_abuse/bod_alcohol_prevalence/atlas.html

Angela
06-05-15, 15:41
http://gamapserver.who.int/gho/interactive_charts/substance_abuse/bod_alcohol_prevalence/atlas.html

The general pattern is always the same. In our particular case, as I said above, culture and genetics reinforce one another. Being sloppily drunk and incapable is antithetical to making a "bella figura".

However, this is changing somewhat among younger people. Part of the fault lies in the fact that they are emulating the behavior of northern Europeans and Americans that they see in the media. That's the strength of cultural influences.
http://news.bbc.co.uk/2/hi/uk_news/7093143.stm

LeBrok
06-05-15, 17:09
http://gamapserver.who.int/gho/interactive_charts/substance_abuse/bod_alcohol_prevalence/atlas.html

Interesting case is Hungary. They have twice the alcoholism compared to surrounding countries. They also have higher ANE level than them.

AgnusDei
15-05-15, 13:46
23andme carried out a similar research on their customers and found a correlation between extraversion and alcoholism in Europe. Like other posters mentioned in this thread, it has more to do with a North South division rather than eye color, or skin color for that matter !

23andMe researchers found that a number of social and cultural traits were strongly associated with a person's predicted genetic ancestry of origin in Europe. Self-reported diagnoses of alcoholism were more common than average among people of predicted Irish ancestry, while people with predicted Balkan ancestry were more likely to describe themselves as extraverts.
These associations and others that we found beg many questions. First do they reflect actual traits among people of different European ancestry or are they simply a reflection of cultural stereotypes among 23andMe customers? More intriguing is the question of whether these traits are influenced by genetics. While the statistical correlations in the data are strong, we still don’t have a complete picture of why these traits appear to separate according to ancestry.
https://www.23andme.com/you/23andwe/discoveries/pca_sociocultural/
http://spittoon.23andme.com/wp-content/uploads/2011/10/pca_sociocultural_plots.png

Angela
15-05-15, 16:04
They framed the questions judiciously, I think, but it doesn't seem to me that it's just a question of people believing the stereotypes about themselves. You'd have to be blind not to notice these differences as you travel around Europe.

I'm with LeBrok; I think it may have something to do with adaptation genetically and culturally to different lifestyles. I don't know if you're read Matthiesen et al, but it's very interesting.
"Eight Thousand Years of Natural Selection in Europe"
http://biorxiv.org/content/biorxiv/early/2015/03/13/016477.full.pdf

It's also discussed here:
http://dienekes.blogspot.com/2015/03/natural-selection-and-ancient-european.html

Sile
15-05-15, 20:03
Eye color was not directly passed down to the present day without frequencies going in all directions in differnt time periods. We can see in the Haak data eye color frequencies had more to do with geography and time period than genetics(besides WHG). So, associating a trait that is associated with an eye color to an ancient group might not work.

All the LBK_EN in haak paper had Hazel, Blue, Green or Grey eyes....none had Brown eyes. The Brown eyes in majority came in with a "younger " group ( less than 4500 years ago )

If you also read the paper, he states the new migrations of people had nothing in common with the LBK_EN ( Anatolians ) and the line of cutoff/difference in years is 4500 years..............so anyone before this period is one group and anyone after is a completely different other group

Sile
15-05-15, 20:05
23andme carried out a similar research on their customers and found a correlation between extraversion and alcoholism in Europe. Like other posters mentioned in this thread, it has more to do with a North South division rather than eye color, or skin color for that matter !

https://www.23andme.com/you/23andwe/discoveries/pca_sociocultural/
http://spittoon.23andme.com/wp-content/uploads/2011/10/pca_sociocultural_plots.png

I do not trust any surveys which give results via todays national boundaries ...................it is impossible to believe