October 14, 2010

African admixture in the Near East: where from?

Here is the result of running ADMIXTURE for K=5 using 275K SNPs on the combined HGDP + HapMap African and West Asian populations, also including Adygei and Tuscans. The populations are in order: Luhya, Maasai, Tuscans, Yoruba, Adygei, Bedouins, Druze, Mozabites, Palestinians.
At this level of detail, Africans are divided into three clusters which can be labeled Sub-Saharan (red), East African (blue), and "Mozabite" or North African (purple). Europeans and West Asians form the green cluster, while the Arab samples have a substantial contribution of the yellow cluster.

Here are the admixture proportions:

African admixture in the two European populations is probably in the limits of statistical noise and consists of "Mozabite" (0.4%) for Tuscans and "E African" for Adygei (0.6%).

Druze, an Arab population that was religiously isolated from Arab Muslims for about a thousand years seems to have correspondingly missed most African admixture, registering 0.6% "Mozabite" and 1.1% "E African".

Non-Druze Arabs have clear traces of African admixture both in the form of "Mozabite" North African (4.5% for Palestinians, 4.9% for Bedouins), E African (6% for Palestinians and 5.7% for Bedouins) and a little Sub-Saharan (1.3% for Palestinians and 2.1% for Bedouins).

I had pointed the mainly eastern African admixture in Near Eastern Arabs a year ago in my review of HAPMIX. Clearly Maasai are a better stand-in than the Yoruba for whatever African ancestry Arabs have.

It is quite interesting to note the genetic distance (expressed in Fst) between the five inferred clusters:

We can plainly see that proximity to Eurasians increases in the order of Sub-Saharan, East African, "Mozabite". I have little doubt that Somalis and Ethiopians from East Africa would occupy an intermediate position between Maasai from Kenya and "Mozabites" in that order.

An interesting observation is that the "Arab" cluster is slightly more distant to all African clusters than the European/W Asian cluster is. This might seem perplexing as geography might dictate that it should be closer to the African clusters.

However, this is not very surprising to me, as there was gene flow between West Asia and Europe and Africa in old times, evidenced by such things as the presence of Eurasian Y-haplogroup R-V88 in Africa and African haplogroup E1b in Europe and West Asia.

The original Arab ancestors, were probably haplogroup J1e-bearing Semites exploiting arid environments of West Asia. Present-day Levantine Arabs (especially Bedouins, in the available samples) maintain a strong signal of this component of their ancestry, admixed, however, principally with the original Tuscan- and Adygei- like West Asians, and secondarily with E and N Africans.

Revisiting GenomesUnzipped "Ashkenazi Jewish" admixture

There were two individuals in my recent post who showed some evidence of "Ashkenazi Jewish" admixture (DBV001: 100% and VXP001: 32%). I list in the comments of that post some possible explanatios for why VXP001 (who has no knowledge of Jewish ancestry) might get such a result. Naturally, using 275K SNPs is better than the 192 of EURO-DNA-CALC, so I did a separate run that included these two individuals.

The results are:

DBV001: 85.1% European/W Asian, 10.5% "Arab", 0.5% "E African", and 3.8% "Mozabite". This is entirely consistent with full known Jewish ancestry. The closest population to the Middle Eastern component of Jews are presumably the Druze, who have about 16.9% of the "Arab" (which should probably be relabeled "Semitic") cluster. Ashkenazi Jews are known to be intermediate between Levantine and European populations, and DBV001's result is entirely consistent with this.

As I've mentioned before, the exact percentage of Middle Eastern ancestry in modern European Jews is difficult to estimate, as this would depend on determining the exact percentage of "European/W Asian" and "Semitic" components was present in their gene pool before they settled in Europe. If, for example, they were 100% in the "Semitic" cluster, then DBV001 would be about 10% of Middle Eastern ancestry, but if they were like modern Druze, then this percentage would be 100*10.5/16.9 = 62.1%. The truth is probably somewhere in between.

VXP001: A shorter story, as VXP001 comes out 100% "European/W Asian". Thus, I am inclined to believe that VXP001's AJ score is either due to the small number of markers, or to a European-origin component in the composite Ashkenazi Jewish gene pool that he happens to share.

UPDATE (Oct 23): A much more detailed analysis of Genomes Unzipped individuals.

17 comments:

  1. Present-day Levantine Arabs (especially Bedouins, in the available samples) maintain a strong signal of this component of their ancestry, admixed, however, principally with the original Tuscan- and Adygei- like West Asians, and secondarily with E and N Africans.

    Were the pre-Arab people of the Levant genetically like Tuscans and the Adygei? I am skeptical of that claim. In any case, the true proxies for the pre-Arab population of the Levant is the Semitic-speaking indigenous Christians of the Levant (especailly the ones away from Crusader contact), not Tuscans or the Adygei. If they are tested, they may show up genetically Druze-like rather than Tuscan or Adygei-like.

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  2. VXP001: A shorter story, as VXP001 comes out 100% "European/W Asian". Thus, I am inclined to believe that VXP001's AJ score is either due to the small number of markers, or to a European-origin component in the composite Ashkenazi Jewish gene pool that he happens to share.


    I'm very interested in more on this, as this is exactly what I expect based on my parents and my results from 23AndMe/HIR Search.

    My father has an Ancestry Finder match with a guy from Crete, who happens to be mtDNA K1a1b1 - usually associated with Ashkenazi Jewish descent.
    Both he and I also are related - via HIR Search - with an Assyrian Christian from Iraq also??!! I've seen people on DNA Forums claim that the Assyrians are most like the original Jews than the Druze or Samaritans.
    My father also shares a segment with 9 Russians, 2 of which are identified as Ashkenazi Jewish.
    On Polako (Davidski's) BGA plots, my father shows as having 5.96% Central Russian (Chuvash) heritage - which is the highest of the 7 Irish sampled - my mother is 4.70%.

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  3. Who said anything about "seafaring"? You are imagining things, Onur bey.

    You mentioned coastal distribution, but I agree with you that coastal distribution doesn't just mean seafaring. What is really important here is that both the original Arabs in Arabia and the other Arabs are in general close to the Mediterranean-Red Sea coastal routes, irrespective of whether they are used by sea or land, and that should make them open to the effects of the coastal gene flow from Africa that you claim and surely much more than the Adygei.

    but if you prefer to explain it in terms of admixture with "more eastern" Caucasoids, that would not alter my thesis significantly, as the "more eastern" Caucasoids would also have little opportunity to experience the gene flow I'm talking about.

    But it would reduce the need to resort to your gene-flow-from-Africa hypothesis, if not completely remove it, to explain the situation.

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  4. Look, Arabs are indeed closer to Africa, that's why they have so much East African admixture.

    But I am not speaking about their more recent admixture, but of the state of their UNADMIXED cluster.

    I'm pretty sure that the original European cluster (prior to e.g., the movements of genes marked by R-V88 and E1b) was more distant than the one observed now.

    Indeed, if we think about it, Caucasoids are closer to Africans than Mongoloids are. In a pure Out-of-Africa scenario this should not have been the case, as the evolutionary time-of-separation between Africans and Eurasians (east and west) would have been the same.

    However, human populations do not really evolve tree-like, but there is lateral gene flow among branches of the tree. It is this lateral gene flow that has brought Caucasoids and Africans closer to each other with respect to Africans and Mongoloids, and prehistoric processes affected some non-Arab Caucasoids while historic ones may have affected the Arabs more.

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  5. Look, Arabs are indeed closer to Africa, that's why they have so much East African admixture.

    But I am not speaking about their more recent admixture, but of the state of their UNADMIXED cluster.


    I already know these. I too was talking about the yellow cluster.

    I'm pretty sure that the original European cluster (prior to e.g., the movements of genes marked by R-V88 and E1b) was more distant than the one observed now.

    Indeed, if we think about it, Caucasoids are closer to Africans than Mongoloids are. In a pure Out-of-Africa scenario this should not have been the case, as the evolutionary time-of-separation between Africans and Eurasians (east and west) would have been the same.

    However, human populations do not really evolve tree-like, but there is lateral gene flow among branches of the tree. It is this lateral gene flow that has brought Caucasoids and Africans closer to each other with respect to Africans and Mongoloids, and prehistoric processes affected some non-Arab Caucasoids while historic ones may have affected the Arabs more.


    I want to make an addition to these:

    Judging by the non-existence of the Negroid components in all non-Arab and non-Berber Caucasoids (I am excluding the noise seen in some analyses), their African admixture is almost completely non-Negroid (mostly very old). Only in some Arab and Berber Caucasoid populations we see genuine Negroid components and their Negroid admixture seems to be relatively recent.

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  6. "human populations do not really evolve tree-like, but there is lateral gene flow among branches of the tree".

    Isn't that the basis of the 'regional continuity theory'?

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  7. Ashkenazim likely have between 4% to 27 % East African -mainly- and in minor South Saharan source markers, even Y and mDNA signals like a genetic landscape of ME of ancient times. The ”L1” and "L2" mtDNA marker is present in the two populations – Ashkenazim and African Ethiopian Jews - also the derived and sibling mtDNA Hg "M" and "N1", as well as the Y markers Hg E3b and 4s too, all of this from East Africa and so. (Also is watching in autosomal markers in minor as well) They belong respectively at one of the three nucleous or center jewish ancient populations, that evolving the called "Syrian-European nucleous"(helenistic and Roman times).
    The oldest center –Ethiopians likely belong these- were that developed in Napata and Elephantine (Kush) and whose nucleous or center was after Alexandria, and I called "Coptic Nucleous" derived in two bias, and split forwards the North via Europe -intermixed with the Syrian Europe nucleous- or the South, via Nile and the Horn Of Africa.
    The "Babilonian and Persian nucleous" is other of the above three mentioned centers and included Bukara, Iranian and Iraki mainly.
    All of this Nucleus take Judaea and Israel like a axis or pendulum.
    Another fourth Nucleous or center I call "East Europe" -not mainly conected with ME-, is not ancient like the three others and was the Jewish Khazar Empire stiring into Askenazy current population and others. All of this events were naturaly intrajewish asimilations in all jews current populations.
    The Ashkenazim hyperhaploydia and heterozygosis that could cluster these Ashkenazim populations everywhere you want (not common in isolated population, the same for mtDNA coming in great rate from host population) is explained by the superposition and overlay of diverse fount or source population , that are all of this of Jewish origin (that consider converted into intraJewish assimilations) , one coming from the “Syrian European nucleous” – that Sephardic as well as preAshenazim bring inside -. The other convergence were the “Coptic Jewish nucleous”, coming from Alexandria, the main and largest Judaic center in ancient times – the buried and graves in Jewish graveyards and catacombs of Tuscan, and Alsace as too Rhineland cities take a lot of Egyptian ornaments and display figures from these, as well as Y and mtDNA markers - . The great Jews migration from Egypt beginning after the Muslim invaders from Arabia in the VII AE century. The “Babylonian and Persian nucleous” take place and contacts newly with and when the “preAshenazim second fase” were migrating to the East Europe. A remarkable contact was with the fourth “East Europe Jews nucleous”-not related or little related with ME-, with the descendant of the Jews Khazarians ones, spreading every where and carrying a lot of East Europe and Eurasian markers. That happen between the XI and XII century AE.
    Remember also that Ethiopian Jews and non Jews are closely between them and are related in a whole to Middle Eastern by languages, traditions and genes associated too with the Horn of Africa. It is the difference between Hindu people – without these close relations with ME- and Ethiopians in Whole as well.
    See, Table 2. Haplogroup distribution in non-Jewish local populations and Jews
    From: Ashkenazi Jewish mtDNA haplogroup distribution varies among distinct subpopulations: lessons of population substructure in a closed group
    Jeanette Feder, Ofer Ovadia, Benjamin Glaser and Dan Mishmar
    See: when in other papers like this too, for example, Polish Jews mtDNA L1,L2 close to 4% Polish non Jews are 0% ; also see tables about mtDNA "L2" and "N1" or "M" markers in Behar et al papers.

    Dr. Hector Horacio Otero Cohen.
    Argentina

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  8. Ashkenazim likely have between 4% to 27 % or more East African -mainly- and in minor South Saharan source markers, even Y and mDNA signals like a genetic landscape of ME of ancient times. The ”L1” and "L2" mtDNA marker is present in the two populations – Ashkenazim and African Ethiopian Jews - also the derived and sibling mtDNA Hg "M" and "N1" from "L3", as well as the Y markers Hg E3b and 4s too, all of this from East Africa and so. (Also is watching in autosomal markers in minor as well) They belong respectively at one of the three nucleous or center jewish ancient populations, that evolving the called "Syrian-European nucleous"(helenistic and Roman times-of profusus and lavish proselitism with genetic inlays-).
    The oldest center –Ethiopians likely belong these- were that developed in Napata and Elephantine (Kush) and whose nucleous or center was after Alexandria, and I called "Coptic Nucleous" derived in two bias, and split forwards the North via Europe -intermixed with the Syrian Europe nucleous- or the South, via Nile and the Horn Of Africa.
    The "Babilonian and Persian nucleous" is other of the above three mentioned centers and included Bukara, Iranian and Iraki mainly.
    All of this Nucleus take Judaea and Israel like a axis or pendulum.
    Another fourth Nucleous or center I call "East Europe" -not mainly conected with ME-, is not ancient like the three others and was the Jewish Khazar Empire stiring into Askenazy current population and others. All of this events were naturaly intrajewish asimilations in all jews current populations.
    The Ashkenazim hyperhaploydia and heterozygosis that could cluster these Ashkenazim populations everywhere you want (not common in isolated population, the same for mtDNA coming in great rate from host population) is explained by the superposition and overlay of diverse fount or source population , that are all of this of Jewish origin (that consider converted into intraJewish assimilations) , one coming from the “Syrian European nucleous” – that Sephardic as well as preAshenazim bring inside -. The other convergence were the “Coptic Jewish nucleous”, coming from Alexandria, the main and largest Judaic center in ancient times – the buried and graves in Jewish graveyards and catacombs of Tuscan, and Alsace as too Rhineland cities take a lot of Egyptian ornaments and display figures from these, as well as Y and mtDNA markers - . The great Jews migration from Egypt beginning after the Muslim invaders from Arabia in the VII AE century. The “Babylonian and Persian nucleous” take place and contacts newly with and when the “preAshenazim second fase” were migrating to the East Europe. A remarkable contact was with the fourth “East Europe Jews nucleous”-not related or little related with ME-, with the descendant of the Jews Khazarians ones, spreading every where and carrying a lot of East Europe and Eurasian markers. That happen between the XI and XII century AE. Note that population events like bottleneck, loosing and losing markers, marriage with local women at the first jews setting community and others comparative few or not, carring from M.E.
    Remember also that Ethiopian Jews and non Jews are closely between them and are related in a whole to Middle Eastern by languages, traditions and genes associated too with the Horn of Africa. It is the difference between Hindu people – without these close relations with ME- and Ethiopians in Whole as well.
    See, Table 2. Haplogroup distribution in non-Jewish local populations and Jews
    From: Ashkenazi Jewish mtDNA haplogroup distribution varies among distinct subpopulations: lessons of population substructure in a closed group
    Jeanette Feder, Ofer Ovadia, Benjamin Glaser and Dan Mishmar
    See: when in other papers like this too, for example, Polish Jews mtDNA L1,L2 close to 4% Polish non Jews are 0% ; also see tables about mtDNA "L2" and "N1" or "M" markers in Behar et al. papers.

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  9. Yes that makes more sense to me, I am afraid my ethnicity is rather simply west European without much of an exotic component. Assuming that the result of the first test is not only noise it may be interesting to figure out what is the source of that shared Ashkenazi/European component.

    Thank you very much for this analysis though, I found it interesting.

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  10. Pconroy writes: “mtDNA K1a1b1 – usually associated with Ashkenazi Jewish descent”.

    But what are you saying? Everything you say is rough: “De bello gallico” is “The gallic wars”, actually “The gallic war” etc. I think you should mind a little bit before speaking or writing. MtDNA K1a1b1 is above all European and with 9932A (like me) above all Italian. I cited the greatest experts on this: Ian Logan and William Hurst. K1a1b1a is above all Ashkenazim, and we should find where they took it. MtDNA K hasn’t so far been found in tombs around Jerusalem and we shall see in the future if ancient Jews had it or not.

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  11. Gioiello,

    I've seen you write your theory that almost every European lineage (male and female) is derived from Tuscany, and especially that Ashkenazi Jews are Tuscans in disguise...

    Did it ever dawn on you that Central Italy - the area around Rome, including Tuscany - was one of great mixing of peoples from all over Europe, North Africa and the Middle East (including Judea) - except North Eastern Europe and Ireland - for over 500 years. So where else exactly would you expect to find samples of most types of DNA in Europe, but in this very area, where they historically mixed.
    Everyone knows you don't want to hear this answer, but it's the truth!

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  12. If this was true, we wouldn't understand why Tuscans, with Sardinians, North Italians, French, Orchards, Adygeys etc. are one of the fundamental population of Europe.
    I sent my raw data to Dienekes (from 23andMe and deCODEme) and I am waiting for a new run on his calculator. I am open to every truth and probably not everyone is.

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  13. The Jews, Sephardi and Ashkenazim, are not intermediate between Europeans and Middle Easterners. The position of Jews on MDS plots is more an artifice of the lack of the spectrum of European, Middle Eastern and Caucasian genetic reference groups that show the true genetic picture of West Eurasia. There is no sharp genetic boundary between Europe, the Middle East or the Caucasus. The Italians are the most genetically diverse Europeans and there is a lack of samples from south of Tuscany in peninsula Italy. No Sicilian Italian samples. No Greek samples. No Albanian samples. In fact the SE of Europe is totally neglected. The Middle East is similarly neglected. No Anatolians. No Syrians. No Lebanese. No Egyptians. No Jordanians. The reference group for Europe is rather stuck with NW Europeans. Given the lack of a proper representation of Europe, the Middle East or the Caucasus region there appears a divide between Europe and the Middle East when in fact the space between the European Tuscan Italians and the Jews will be filled with Mezzogiorno Italians, Greeks, Albanians, other Balkan European, Turks and Levantine Middle Easterners. Then the problem will be to set the boundary between Europe and the Middle East. That will be difficult as the Jews will overlap with those SE Europeans and Southern Italy, Greece and so on will end up outside Europe.

    FTDNA in their Population Finder admit in their explanatory information that they cannot separate SE Europeans from Jews from Middle Eastern people using the SNPs for that test. Prof. McDonald often states to Greeks, Southern Italians and other SE Europeans that he cannot tell whether they are SE Europeans or Jewish people on their results.

    I think Dienekes is shooting himself in the foot as many Magna Graecia Europeans will end up in the Jewish cluster. It is already happening.

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  14. but it's the truth!

    We don't know the demographic effects of the Roman-era migrations (including slaves) to Italy. So we cannot a priori associate the genetic diversity of Italians with the Roman-era migrations.

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  15. To put this in perspective, nearby Caucasoid groups differ from each other in the order of Fst=0.01, and Caucasoids differ from Mongoloids by about Fst=0.1. The low-level Central Asian Caucasoid+Mongoloid admixture in the genome of Anatolian Turks shifts them away from Greeks.

    Dieneke, do you have Fst values of Turks and their geographical neighbors that I can look at? I've seen their ADMIXTURE and PCA results, but, as you know, Fst is more informative about genetic distances.

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  16. pconroy said...
    "Both he and I also are related - via HIR Search - with an Assyrian Christian from Iraq also??!! I've seen people on DNA Forums claim that the Assyrians are most like the original Jews than the Druze or Samaritans."

    You may be referring to the apparent relationships I have pointed out in recent weeks. I post under the pseudonym, "Handschar," on DNA-Forums. I am also the admin of the Aramaic DNA Project at FTDNA. Behar's Iraqi and Iranian Jews, and the samples I and other Assyrians have submitted for inclusion in the "Eurogenes Project," on the many plots thus far created by David W, consistently cluster with one another. What do these three populations have in common? All practiced extreme forms of endogamy for many, many centuries. At least since the advent of Islam, and possibly for many centuries beyond. They also shared a common language for many centuries, Aramaic. Aramaic remains the vernacular of the Assyrians, and some Iraqi and Iranian Jews.

    Recent very minor admixture of Ashkenazim and Sephardim in the two Jewish groups, and Armenian blood in the Assyrian population have failed to significantly impact the apparent affinity between the groups. If not for the recent minor admixture, the proximity between the Iraqi and Iranian Jewish, and Assyrian populations, might have been even greater. Furthermore, beyond autosomal affinities, Iraqi Jews (Nebel et al., 2001), and Assyrians, display more or less consistent Y-DNA haplogroup frequencies.

    As a demonstration of the extreme form of endogamy practiced by the Assyrians over the millennia, my 23andMe experience, in my opinion, is telling. Of the fifteen Assyrians of Hakkari Province, West Azerbaijan Province, and North Iraq tested at 23andMe, I am a predicted cousin of each and every one of the fifteen Assyrians. This is a rate of consanguinity that if representative of the Assyrian population in general, would rival, if not eclipse that of the Ashkenazim.

    If Dienekes wishes, I would be more than willing to provide the complete 23andMe genome files of family members for inclusion in his future projects. I can be reached at AramaicDNA@gmail.com.

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  17. Alfio, your quotation is from Ponto, not mine.

    ReplyDelete

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