February 14, 2014

Big genetic atlas paper

Nicholas Wade reports in the NYT:
Tracing Ancestry, Researchers Produce a Genetic Atlas of Human Mixing Events 
By NICHOLAS WADE    FEB. 13, 2014

... Now, geneticists applying new statistical approaches have taken a first shot at both identifying and dating the major population mixture events of the last 4,000 years, with the goal of providing a new source of information for historians. 
Some of the hundred or so major mixing events they describe have plausible historical explanations, while many others remain to be accounted for. For instance, many populations of the southern Mediterranean and Middle East have segments of African origin in their genomes that were inserted at times between A.D. 650 and 1900, according to the geneticists’ calculations. This could reflect the activity of the Arab slave trade, which originated in the seventh century, and the absorption of slaves into their host populations. 
The lowest amount of African admixture occurs in the Druse, a religious group of the Middle East that prohibited slavery and has been closed to converts since A.D. 1043. 
Another mixing event is the injection of European-type DNA into the Kalash, a people of Pakistan, at some time between 990 and 210 B.C. This could reflect the invasion of India by Alexander the Great in 326 B.C. The Kalash claim to be descended from Alexander’s soldiers, as do several other groups in the region.

A lot of things peoples say about themselves aren't completely made up.
The genetic atlas of human mixing events was published on Thursday in the journal Science by a team led by Simon Myers of Oxford University, Garrett Hellenthal of University College London and Daniel Falush of the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany. Having sampled genomes from around the world, they found they could detect about 95 distinguishable populations. 
Though all humans have the same set of genes, their genomes are studded with mutations, which are differences in the sequence of DNA units in the genome. These mutations occur in patterns because whole sets of mutations are passed down from parent to child and hence will be common in a particular population. 
Based on these patterns, geneticists can scan a person’s genome and assign the ancestry of each segment to a particular race or population. 
The team led by Dr. Myers has developed a statistical technique for identifying the chromosomal segments with particular precision. This enables them to perform a second feat, that of assigning a date to the one or more mixing events that have affected a population. 
... One of the most widespread events his group has detected is the injection of Mongol ancestry into populations within the Mongol empire, such as the Hazara of Afghanistan and the Uighur Turks of Central Asia. The event occurred 22 generations ago, according to genetic dating, which corresponds to the beginning of the 14th century, fitting well with the period of the Mongol empire.

... Dr. Myers and his colleagues have detected European ancestry that entered the Tu people of central China between the 11th and 14th centuries; this, they surmise, could be from traders traveling the Silk Road. 
They find among Northern Italians an insertion of Middle Eastern DNA that occurred between 776 B.C. and A.D. 550, and may represent the Etruscans, a mysterious people said by the ancient Greek historian Herodotus to have emigrated from Lydia in Turkey. 

The Etruscans apparently turned into the Tuscans (e.g., Florence). They've always had a lot of style.
The Myers group has posted its results on a web page that records the degree of admixture in each population. The English, however, known to be a rich medley of Celts with invaders such as the Angles, Saxons, Jutes, Danes and Norwegians, carry the notation “No strong evidence of admixture.” Dr. Myers said his method cannot yet detect genetic mixing between very similar populations, as was the case with the English and their invaders from Scandinavia and Northern Germany.
 
Dienekes has more here:
While reading this study, it is important to remember its limitations. Two are immediately obvious: (i) admixture events can only be detected for the last few thousand years, as this method depends on pattern of linkage disequilibrium which decays exponentially with time due to recombination, and (ii) detection of admixture seems to depend on the presence of maximally differentiated populations from the edges of the human geographical range; for example, the Japanese appear unadmixed even though they are clearly of dual Jomon/Yayoi ancestry. On the other hand, the method does detect the admixture present in the San at a similar time scale. 
The case of Northwestern Europe appears especially striking as none of the populations from the region show evidence of admixture. This may be because the mixtures taking place there (e.g., between "Celts" and "Anglo-Saxons" in Great Britain) involved populations that were not strongly differentiated. Alternatively, population admixture history may have preceded the last few thousand years and is thus beyond the temporal scope of this method.
 
Here's a companion website.
 

46 comments:

  1. As Dienekes says, the claim of admixture in the Sardinians is evidence that a lot of this paper is crap.

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  2. Not bad for a "social construct".

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  3. No genetic mixing among the northern Europeans in the last 3000 years means they need to hurry up and diversify.

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  4. Celts being people who lived in Southern France mostly although pop culture bizarrely have them centred in Sothern Germany where Tuetons were/are. Still a lot of nonesense written about that time.

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  5. I always thought that the Mutt claim for the Brits was prime facia absurd.

    There's practically no difference between blondes and reds in the Isles and the Danes/Norse etc...it there is I can't see it.

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  6. Its funny. The other day I came accross this site

    http://realhistoryww.com/world_history/ancient/Dobruja_Thrace_1.htm

    which seems to take all this mixing/hbd stuff seriously, but came up with the excuse that white people are a albino genetic mutation

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  7. The English, however, known to be a rich medley of Celts with invaders such as the Angles, Saxons, Jutes, Danes and Norwegians, carry the notation “No strong evidence of admixture.” Dr. Myers said his method cannot yet detect genetic mixing between very similar populations, as was the case with the English and their invaders from Scandinavia and Northern Germany.

    Except that the English are not know to be a rich medley of invaders except in the fantasies of historians with their breathless talk about a Saxon holocaust of the Celtic Britons. Stephen Oppenheimer and others have provided a wealth of evidence as to why this is.

    Its mainly that the British started off even before Roman times with a Flemish/Rhenish/Frisian "Saxon" population in the southeast on what the Romans already called "The Saxon Coast", a "Celtic" population in Wales, Cumbria, Cornwall, and highland Scotland related to the Bretons, SW "French" and Galacians, and a Scandanavian population in the northeast and lowland Scotland (Anglia/Danelaw). These groups generally kept themselves seperate due to geography, and the "invasions" such as they were, were a migration of likeminded folk to settle with their kin across the North Sea.

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  8. teen immigrant angst2/14/14, 6:57 AM

    The only thing that actually surprised me to come out of the banal chat-show interviews for "Battle Hymn of the Tiger Cuban-Nigerian Tricultures" is that their eldest daughter is going to join the freaking Army after she graduates. I have always wanted to see one big government scandal that combined the best of Jonathan Pollard & Wen Ho Lee with Jessica Lynch.

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  9. Celts are R1b. Broadly, French AND south Germans are Celts. North and east Germans are not.

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  10. There alot of racial míxing in Italy during the whole Roman period.

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  11. The case of Northwestern Europe appears especially striking as none of the populations from the region show evidence of admixture. This may be because the mixtures taking place there...involved populations that were not strongly differentiated.

    Just give it time.

    The MultiKult is working night and day to solve this problem.

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  12. As Dienekes says, the claim of admixture in the Sardinians is evidence that a lot of this paper is crap.


    "Dienekes says" nothing of the sort.

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  13. .. the ancient DNA evidence as it stands would rather indicate that Sardinians are the best approximation of Neolithic Europeans currently in existence and so are more likely to (mostly) possess a gene pool that traces back to ~8-9 thousand years in Europe.


    I don't know what DNA evidence Dienekes is referring to, but given the known history of Sardinia - it's been invaded in succession by Phoenicians, Carthaginians, Romans, Vandals, Byzantines, Muslims, and on and on - it would be downright bizarre if the people living there were the unadmixed genetic descendants of Neolithic Europeans from 8-9 thousand years ago.

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  14. The Danes are quite an admixture actually. More of a medley than the British Isles.

    At least until the Windrush dumped a load on England.

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  15. Maybe this will all prove to be true, but for now I'll reserve judgment. It all seems too pat.

    They report some Mongol genes found and then deduce it was Genghis Khan. Somebody notify John Kerry quick.

    If this is a real hypothesis not just a curiosity for history buffs, how do you form a 'null hypothesis'? What kind of statistical test would you employ as a check on your own biases?

    Maybe in the original paper there was more substance but this set of correspondences reads like a 'just so' story.

    Albertosaurus

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    1. Kerry is a descendant of Dr Frankenstein.

      Delete
  16. When you look at migration you have to think about destinations and departures. No one moves to Montenegro. Noone migrates to Haiti...

    Certain areas were simply to fierce or tough to bear. The Dinaric Alps are a European genetic reserve area. The same is apparently true for the Basque region.

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  17. The Islands like Sardinia are places IMHO that you leave if you are ambitious. They are generally unsuitable for colonization.

    If you look at the Irish they have successfully colonized much of the world with their DNA, and up to now, managed to keep home as a refuge.

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  18. "The lowest amount of African admixture occurs in the Druse, a religious group of the Middle East that prohibited slavery and has been closed to converts since A.D. 1043."

    Slavery was 'anti-racist' because it increased genetic diversity.

    Anti-slavery was xenophobic, 'racist', and exclusionary since it didn't lead to more genetic diversity.

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  19. "Based on these patterns, geneticists can scan a person’s genome and assign the ancestry of each segment to a particular race or population."

    Poor Lewontin.

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  20. "the Etruscans, a mysterious people said by the ancient Greek historian Herodotus to have emigrated from Lydia in Turkey"

    Interesting. Romans saw the Trojan Aeneas as the founder of the Roman folks, and Troy was in what is today Turkey.

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  21. Celts being people who lived in Southern France mostly although pop culture bizarrely have them centred in Sothern Germany where Tuetons were/are. Still a lot of nonesense written about that time.

    Celts lived all through Europe at one time. They were pushed west and north by the Germans and Romans.

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  22. Thank you, 10:13 AM, for setting 9:48 AM to rights. Now all you have to do is learn to distinguish military operations from interbreeding.

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  23. Love it.

    Sample sizes are waaaaay to small.

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  24. What will happen down the road in a century or so when these groups gain the ability to undo said admixture?

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  25. What about the Finns? Estonians? Hungarians? Linguistically, these groups are pretty isolated from their surrounding areas, but weren't there some admixtures?

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  26. Parts of the world that took part in the slave trade are more diverse than parts of the world that didn't.

    Brazil more diverse than Norway.
    American South more diverse than Maine and Vermont.

    Conclusion: slave trade increased diversity, therefore it was good.

    But refusal to deal in slaves maintained greater homogeneity. BAD!!!

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  27. Gad, you're firing on a lot of cylinders lately. This one I've linked with a quibcag:
    http://ex-army.blogspot.com/2014/02/a-genetic-atlas.html

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  28. all you have to do is learn to distinguish military operations from interbreeding.


    Even an internet nerd should know that interbreeding follows conquest as surely as 9 follows 10. The first thing the conquering soldiers do is rape the local women. If they're an army of occupation they end up marrying them.

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  29. The Islands like Sardinia are places IMHO that you leave if you are ambitious. They are generally unsuitable for colonization


    People have been invading and colonizing Sardinia for thousands of years. The same is true of all the islands in the Med, which was the interstate highway of the ancient world. Being on an island in the Med guaranteed that every powerful group who sprang up around it would come calling on you at some point.

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    1. Ambitious folk tend to leave smallish islands.

      Check your sources.

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  30. "Celts are R1b. Broadly, French AND south Germans are Celts. North and east Germans are not."

    The Danes - and by extension Anglo-Saxons -are c. half R1b.

    West is Celtic, North is Germanic. Northwest is 50/50.

    Plus they must have been closely related to begin with.

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    1. Here is what happened.

      The Scandies liked em some freckled redheads so they kidnapped em.

      But, the English liked em some blondes so they hooked up with Canute and Thorkelson and guys like Godwinson kidnapped or married Danes and Swedes and Poles. Same as it ever was.

      This probably predates the Romans.

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  31. Geoff Matthews:

    What about the Finns? Estonians? Hungarians? Linguistically, these groups are pretty isolated from their surrounding areas, but weren't there some admixtures?

    Finns and Estonians and Karelians are "native" inhabitants of the general area between Helsinki and Murmansk and Archangelsk.

    Hungarians are a Central Asian warrior tribe that took over a mixed Roman-Germanic-Slavic pastoral population and imposed their language upon them as the ruling nobles. In more recent times since 1848, hundreds of thousands if not a million or more of Germans living in the Hungarians basin gave up that ethnicity and became Hungarians. If you are looking for relatively pure Hungarians, look at the Szekelers in Transylvania.

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  32. Some people seem to think Y-chromosome or mitochondrial haplotypes are similarly informative to principal component analysis on the whole genome. They must believe a piece of steak that gets stuck in your tooth is as nourishing as the whole dinner.
    As for 4:02 PM, he no doubt expects the Japanese of the future to look like GIs.

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  33. The numbers are too low for anything conclusive. Indian - 13, Russian - 25. Too much hype and not nearly enough data for "genetic atlas of human admixture history".

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  34. Anon:

    Celts lived all through Europe at one time. They were pushed west and north by the Germans and Romans.

    Ummm ... no.

    Gauls lived in southern France and the Atlantic Littoral. All the ancient authorities are perfectly clear about that. The inhabitants of the La Tene/Halstatt area termed Celts by some are now and were then Germans, which is why the ancients like Cassius Dio wold write: "some of the Celts, whom we call Germans". Some people like to confuse the word "Galatian" with "Gaul" or "Gael" as well, even though St. Jerome notes they were called this because of "their shiny complexion" and "milky-white necks". Compare to the Salic Law premable, which speaksof the Franks being renowned for their pale white skin. St. Jerome also noted the Galatians as speaking a language similar to that of Trier. Trier has been a German city back to Roman times.

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  35. Now as Wade mentions in this NYT article, it's becoming clear that the Irish and Brit genes are "not strongly differentiated." Interesting because I've come across people who believed that relatively low Irish IQ scores compared to their Brit neighbors were a result of their Celtic ancestry. But IQ scores have converged over the past few decades as Ireland became richer, as you would expect of two groups who are genetically similar but face very different cultural and education environments.

    Note also that Afghans and Swedes aren't all different genetically either, but again there is a massive IQ difference.

    Point is liberals will be proven wrong about how genetics are irrelevant in determining intelligence. But liberals will be proven right about how environmental factors predominate over genetic factors.

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  36. I like how they skip over Indonesia, the fourth most populous nation, entirely. Maybe they looked at both its many separate ethnicities and its long history as the trading crossroads of the world and said screw it.

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  37. Even an internet nerd should know that interbreeding follows conquest as surely as 9 follows 10.
    --anonymous Internet nerd

    By that logic, the soldiers of Alexander, Cæsar, Genghis, and Hernán Cortés died virgins.

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  38. When "African" genes are referred to, the authors generally neglect to mention which race they mean. After all, Africa was historically home to Caucazoid Hamitics in the north, Congoids (blacks) in the central parts, and Capoids (Bushmen) in the south. The territories and cultures of each have ebbed and flowed over the millennia, of course, and slave-taking further churned things. But we ought to be more precise.

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  39. "I don't know what DNA evidence Dienekes is referring to, but given the known history of Sardinia - it's been invaded in succession by Phoenicians, Carthaginians, Romans, Vandals, Byzantines, Muslims, and on and on - it would be downright bizarre if the people living there were the unadmixed genetic descendants of Neolithic Europeans from 8-9 thousand years ago."



    You should have stopped at "I don't know what DNA evidence Dienekes is referring to" then.

    99% of the comments in this thread are crappy but that's what happens when you combine population genetics with politics.

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  40. """""For instance, many populations of the southern Mediterranean and Middle East have segments of African origin in their genomes that were inserted at times between A.D. 650 and 1900, according to the geneticists’ calculations. This could reflect the activity of the Arab slave trade, which originated in the seventh century, and the absorption of slaves into their host populations."""""""



    What this person fails to read about the Arabian slave trade during this era was that the vast majority of sub Saharan African slaves were made eunuchs to serve the vast harems of the various middle eastern rulers of the time. Thomas Sowell in his books on world history and slave trade discusses the Arabian slave trade and makes this point. Sowell contends that very little black Africans during the 650-1800 era during the time of the Arabian slave trade were primarily


    Bottom line: The men were made eunuchs to serve as guards in the harems and eunuchs can't pass their genes on. So any African DNA would have to have come by way of the women, who would also be taken to serve in middle eastern slave markets and to primarily serve in the harems as Arabian rulers concubines.

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  41. "Some people seem to think Y-chromosome or mitochondrial haplotypes are similarly informative to principal component analysis on the whole genome. They must believe a piece of steak that gets stuck in your tooth is as nourishing as the whole dinner."

    It's important to look at all three: y dna, mtdna and aDNA, as any mismatch is probably a clue something significant happened.

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  42. Re: the Sardinians, we know that they don't look like a population that is admixed between relatively large fractions of two different populations. Not in the way that other Europeans can.

    At the same time, given their position and history, it wouldn't be surprising if, compared to say Norway, they had more separate very small episodes of mixture (like very small bands of Arabic / North African / Viking warriors and so on) that quickly got broken up and distributed through the population.

    These would affect their ancestry very little and those would be harder to make out against their genetic background, but would match up with history.

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  43. Genes and Haplogroups = Hardware.

    Language and Culture = Software.

    In the end, it is all about cultural-linguistic space.

    If these Genes, or those Haplogroups, wandered off, into the Cultural-Linguistic space of the Greeks...the Hellenization process would make them Greek, eventually - after 4 generations or so.

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