What does "Iranian related ancestry" mean?

Shahmiri

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I have read it several times in recent genetic studies but I see different interpretations of it, is it the same Anatolian-related ancestry which relates to the spread of farming to the west? So why do they call it Iranian related ancestry? Of course haplogroup J2 existed in both in Anatolia and Iran, does it talk about just this haplogroup, not even one of its subclades? What culture is associated with Iranian related ancestry? Please also talk about the time span.
 
Shahmiri: Take a look at this paper. Maybe it can help out. The paper suggest most closely related to the Caucus Hunter Gathers from just to the North. No direct link to modern European populations, so probably came in with some other direct source (e.g., Yamnaya). This paper suggest no genetic relationship with the Anatolian Farmers further to the West.

https://www.nature.com/articles/srep31326
 
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Shahmiri: Take a look at this paper. Maybe it can help out. The paper suggest must closely related to the Caucus Hunter Gathers from just to the North. No direct link to modern European populations, so probably came in with some other direct source (e.g., Yamnaya). This paper suggest no genetic relationship with the Anatolian Farmers further to the West.

https://www.nature.com/articles/srep31326


About Yamnaya, it seems to be clear that this "Iranian related ancestry" is a different thing because they talk about "Steppe-related ancestry" as another thing, I can't find the answer of my question in the paper that you mentioned.
 
Shahmiri: Well lets forget about the steppe, the abstract is pretty clear Iran_Neolithic is distinct from the Anatolian_Farmer DNA however, there is cultural association between Anatolia and Western Iran.

"While somedegree of cultural diffusion between Anatolia, Western Iran and other neighbouring regions is possible,the genetic dissimilarity between early Anatolian farmers and the inhabitants of Ganj Dareh supports amodel in which Neolithic societies in these areas were distinct."


This paper by Mathieson et al 2016 (Figure 2) based on how I interpret it seems to show Iran_Neolithic having close genetic similarity/affinity with the CHG per the plot.

https://www.nature.com/articles/nature25778
 
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Shahmiri: Well lets forget about the step, the abstract is pretty clear Iran_Neolithic is distinct from the Anatolian_Farmer DNA however, there is cultural association between Anatolia and Western Iran.

"While somedegree of cultural diffusion between Anatolia, Western Iran and other neighbouring regions is possible,the genetic dissimilarity between early Anatolian farmers and the inhabitants of Ganj Dareh supports amodel in which Neolithic societies in these areas were distinct."


This paper by Mathieson et al 2016 (Figure 2) based on how I interpret it seems to show Iran_Neolithic having close genetic similarity/affinity with the CHG per the plot.

https://www.nature.com/articles/nature25778

Do you mean CHG is the direct source that you mentioned? I still can't find the answer, in the Neolithic age, some people from Iran migrated to South of Caucasus (however it cannot be called a migration, both lands are in the same region), then what happened? How this ancestry reached south of Europe after 2,000 BC? Who were these people?
 
Shahmiri: I said genetic affinity between CHG and Iran_Neolithic. As for the Yamnaya, they were among the people who brought Steppe ancestry to the West.

Here is the supplementary information for the Lazaridis et al 2016 paper (and main paper). There is a large section in the Supplement on Iran_Neolithic and the evidence suggest that the Iran_Neolithic are in continuity with the Caucus Hunter Gathers from the North, so in a time series, since HG predate Neolithic, I think it suggest CHG were a direct source to Iran_Neolithic. Now that is my reading of the paper. Take a look at it and see what you think.

https://www.nature.com/articles/nature19310

https://static-content.springer.com...ects/41586_2016_BFnature19310_MOESM96_ESM.pdf


But the Bronze Age is much later, so some Iran_Neolithic migrating to the North and and then some of that ancestry being part of Steppe peoples does not negate the CHG being a early source for the Iran_Neolithic populations. Again, that is what I get from the papers. I am not saying my interpretation is 100% accurate as I have not really read as much on ancient DNA studies from that region of the world as opposed to studies on Italian DNA, Ancient Rome, etc. Take a look at the papers and see what you think.
 
Shahmiri: I said genetic affinity between CHG and Iran_Neolithic. As for the Yamnaya, they were among the people who brought Steppe ancestry to the West.

Here is the supplementary information for the Lazaridis et al 2016 paper (and main paper). There is a large section in the Supplement on Iran_Neolithic and the evidence suggest that the Iran_Neolithic are in continuity with the Caucus Hunter Gathers from the North, so in a time series, since HG predate Neolithic, I think it suggest CHG were a direct source to Iran_Neolithic. Now that is my reading of the paper. Take a look at it and see what you think.

https://www.nature.com/articles/nature19310

https://static-content.springer.com...ects/41586_2016_BFnature19310_MOESM96_ESM.pdf


But the Bronze Age is much later, so some Iran_Neolithic migrating to the North and and then some of that ancestry being part of Steppe peoples does not negate the CHG being a early source for the Iran_Neolithic populations. Again, that is what I get from the papers. I am not saying my interpretation is 100% accurate as I have not really read as much on ancient DNA studies from that region of the world as opposed to studies on Italian DNA, Ancient Rome, etc. Take a look at the papers and see what you think.

Would you please explain this map:

po9n_steppe.jpg
 
Shamiri: This seems like a repeat of another thread about the spread of Indo-European languages. Not one I really care to get into that much. On a personal note, I am interested in what is the best direct source of Steppe ancestry that entered the Italian mainland, as well as Sicily, Sardinia. All it means is some Iranian related ancestry came into the West via Steppe migration. The Lazaradis et al 2016 paper that I linked indicates that some Iranian-Related ancestry was part of the Steppe, notice related, it could just as easy be CHG.

"Admixture did not only occur within the Near East but also extended towards Europe. To the north, a population related to people of Chalcolithic Iran contributed about 43% of the ancestry of early Bronze Age populations of the steppe. The spread of Near Eastern ancestry into the Eurasian steppe was previously inferred without access to ancient samples, with a population related to present-day Armenians as a suggested source7,8. To the west, the early farmers of mainland Europe were descended from a population related to Neolithic North-Western Anatolians. This is consistent with an Anatolian origin of farming in Europe, but does not reject other sources, as the spatial distribution of the Anatolian/European-like farmer populations is unknown. We can rule out the hypothesis that European farmers stem directly from a population related to the ancient farmers of the southern Levant, however, because European farmers share more alleles with Anatolian Neolithic farmers than with Levantine farmers..."

I am not sure what you are now asking, it seems the goal post are being moved. I think the papers I linked answered your questions, the Iran_Neolithic seems to share genetic affinity with CHG.
 
Mathieson et al 2018 "The Genomic History of Southeastern Europe"

Here is the best explanation from thee paper I cited above. Steppe ancestry is a 3-way admixture, EHG predominate plus some combination of CHG and Iran_NEO.

"We described the individuals in our dataset in terms of their genetic relatedness to a hypothesized set of ancestral populations, which we refer to as their genetic ancestry. It has previously been shown that the great majority of European ancestry derives from three distinct sources23: first, ‘hunter-gatherer-related’ ancestry that is more closely related to Mesolithic hunter-gatherers from Europe than to any other population, and that can be further subdivided into ‘eastern’ (EHG) and ‘western’ (WHG) hunter-gatherer-related ancestry7; second, ‘northwestern-Anatolian-Neolithic-related’ ancestry related to the Neolithic farmers of northwest Anatolia and tightly linked to the appearance of agriculture9,10; and third, ‘steppe-related’ ancestry that appears in western Europe during the Late Neolithic-to-Bronze Age transition, and which is ultimately derived from a population related to Yamnaya steppe pastoralists7,15. Steppe-related ancestry itself can be modelled as a mixture of EHG-related ancestry and ancestry related to Upper Palaeolithic hunter-gatherers of the Caucasus (CHG) and the first farmers of northern Iran19,21,22.'
 
Iranian-related means related to NEOLITHIC Iranians, not later inhabitants of Iran. Iran_N was still very little admixed with more western peoples like Levantines and Anatolian as well as native Eastern Europeans (EHG). It was most closely related to CHG, but not really almost the same genetic structure as I've seen some claim. They are distinct, but close enough and so divergent from the other West Eurasian groups that some ancestry models prefer to use them as roughly the same thing. Iran_N was mostly ANE + Basal Eurasian, plus maybe a minor portion of something East Eurasian blended into that main combination.

The "southern" admixture in Eneolithic Steppe inhabitants seems to be closer to CHG than to Iran_N, and I think that makes sense geographically and archaeologically. Anthony in his latest article says still unpublished Eneolithic Steppe samples prove the archaeological findings that already demonstrated a northward expansion of Caucasian fishers and herders from the North Caucasus up into the steppes via river valleys (e.g. Don). It had started, according to him, between ~6000 and ~4500 B.C.E, that is, before the period Proto-Indo-European was supposed to have been spoken still in completely undivided form. Indeed, Khvalynsk_En samples many hundreds of kilometers away from the Caucasus were already ~25-30% CHG by about ~4000-4500 B.CE., and Vonyuchka and Progress samples just north of the Caucasus were already ~40-50% CHG by ~4000-4200 B.C.E. That suggests to me that the CHG-EHG admixture that created the steppe-related cline was already pretty much formed by ~4500-5000 B.C.E., that is, quite a bit before PIE started to split into distinct languages (and presumably ethnic groups associated with them).
 
Iranian-related means related to NEOLITHIC Iranians, not later inhabitants of Iran. Iran_N was still very little admixed with more western peoples like Levantines and Anatolian as well as native Eastern Europeans (EHG). It was most closely related to CHG, but not really almost the same genetic structure as I've seen some claim. They are distinct, but close enough and so divergent from the other West Eurasian groups that some ancestry models prefer to use them as roughly the same thing. Iran_N was mostly ANE + Basal Eurasian, plus maybe a minor portion of something East Eurasian blended into that main combination.

The "southern" admixture in Eneolithic Steppe inhabitants seems to be closer to CHG than to Iran_N, and I think that makes sense geographically and archaeologically. Anthony in his latest article says still unpublished Eneolithic Steppe samples prove the archaeological findings that already demonstrated a northward expansion of Caucasian fishers and herders from the North Caucasus up into the steppes via river valleys (e.g. Don). It had started, according to him, between ~6000 and ~4500 B.C.E, that is, before the period Proto-Indo-European was supposed to have been spoken still in completely undivided form. Indeed, Khvalynsk_En samples many hundreds of kilometers away from the Caucasus were already ~25-30% CHG by about ~4000-4500 B.CE., and Vonyuchka and Progress samples just north of the Caucasus were already ~40-50% CHG by ~4000-4200 B.C.E. That suggests to me that the CHG-EHG admixture that created the steppe-related cline was already pretty much formed by ~4500-5000 B.C.E., that is, quite a bit before PIE started to split into distinct languages (and presumably ethnic groups associated with them).

Id like to see more evidence for East Eurasian in Iran_N. I also find it hard to believe that that Iran_N has nothing WHG/AHG/UHG related.
 
Another one on which we disagree. :)

They are not identical, but they're pretty damn similar. The way Eurogenes discusses it it's as if they're different "races".

This old Dienekes chart may not be the last word, but it's not bad:

ADMIXTURE.png


The vast majority of the ancestry which went into the steppe people is the same as the vast majority of the ancestry in Iran Neo.

7s1h2yi.png


I think many academics feel it's so difficult sometimes to tell them apart that it's better to just say Iran related.
 
Another one on which we disagree. :)

They are not identical, but they're pretty damn similar. The way Eurogenes discusses it it's as if they're different "races".

This old Dienekes chart may not be the last word, but it's not bad:
The vast majority of the ancestry which went into the steppe people is the same as the vast majority of the ancestry in Iran Neo.

I think many academics feel it's so difficult sometimes to tell them apart that it's better to just say Iran related.

But, see, I feel this depends a lot on the resolution of the admixture graph you're using (which probably reflects the main purpose of the graph in the first place). If you make a, say, K=6 graph using very divergent modern populations, like West Eurasians, East Asians and South Asians, you could mistakenly believe that Spaniards, Russians and Lebanese are very similar. That's why I always interpret these K= admixture graphs very cautiously especially if they'e comparing very divergent ancient populations like ANF and WHG vs. CHG and Iran_N.

That said, as I commented in my earlier post, I think CHG and Iran_N are close enough that they're best seen by most geneticists, particularly in comparison with other genetic structures that later admixed increasingly, as two ends of a shared genetic cline, not as totally distinct populations that can be very easily distinguished.

They're distinguishable on a PCA and do not overlap, and CHG apparently (IIRC) had some EHG-related ancestry while Iran_N had more Basal Eurasian. But that could be just a part of a wide cline from the Caucasus to the Zagros to the Eastern Plateau of Iran (I say that because the recent South Asian paper claims that eastern Iran_N and western Iran_N had diverged much earlier than previously thought, some 10,000 years ago). Since geneticists can't pinpoint where precisely in that cline a given Iranian and Caucasian-related population lived to contribute later to the admixture makeup of a given population, sometimes they think distinguishing both is not worth the effort and they are better understood as more or less the same thing. I doubt all CHG were 100% Satsurblia-like, and for Iran_N we can for ourselves conclude they had some internal genetic structure, because they do not overlap very tightly.

I'm still unable to post my pictures here, I don't know why, but see in Imgur what I mean: https://imgur.com/a/CNkUf5A. The most distant Iran_N samples are not much less different from CHG than the closest Natufian and Anatolia_N individuals. So, certainly very similar, but not exactly indistinguishable. I don't think we disagree about that.
 
But, see, I feel this depends a lot on the resolution of the admixture graph you're using (which probably reflects the main purpose of the graph in the first place). If you make a, say, K=6 graph using very divergent modern populations, like West Eurasians, East Asians and South Asians, you could mistakenly believe that Spaniards, Russians and Lebanese are very similar. That's why I always interpret these K= admixture graphs very cautiously especially if they'e comparing very divergent ancient populations like ANF and WHG vs. CHG and Iran_N.

That said, as I commented in my earlier post, I think CHG and Iran_N are close enough that they're best seen by most geneticists, particularly in comparison with other genetic structures that later admixed increasingly, as two ends of a shared genetic cline, not as totally distinct populations that can be very easily distinguished.

They're distinguishable on a PCA and do not overlap, and CHG apparently (IIRC) had some EHG-related ancestry while Iran_N had more Basal Eurasian. But that could be just a part of a wide cline from the Caucasus to the Zagros to the Eastern Plateau of Iran (I say that because the recent South Asian paper claims that eastern Iran_N and western Iran_N had diverged much earlier than previously thought, some 10,000 years ago). Since geneticists can't pinpoint where precisely in that cline a given Iranian and Caucasian-related population lived to contribute later to the admixture makeup of a given population, sometimes they think distinguishing both is not worth the effort and they are better understood as more or less the same thing. I doubt all CHG were 100% Satsurblia-like, and for Iran_N we can for ourselves conclude they had some internal genetic structure, because they do not overlap very tightly.

I'm still unable to post my pictures here, I don't know why, but see in Imgur what I mean: https://imgur.com/a/CNkUf5A. The most distant Iran_N samples are not much less different from CHG than the closest Natufian and Anatolia_N individuals. So, certainly very similar, but not exactly indistinguishable. I don't think we disagree about that.

Well argued.

So, we actually don't really disagree this time. :)
 
According to Lazaridis et al., CHG could be modelled as ~64.3% Dzudzuana-like plus ~30.3% ANE-like and extra ~5.4 BE, while Iran Neo is better modelled as ~57.7% Dzudzuana-like plus ~32.7% ANE-like and extra ~9.7% BE. These results would mean CHG as ~46.6 WHG-like, 30.3% ANE-like and ~23% BE, and Iran Neo as ~41.8 WHG-like, ~32.7 ANE-like and ~25.5 BE. ANF would have a similar amount of BE.
EHG Karelia is being modelled as ~66% ANE-like plus 34% WHG-like.

It's also said (https://www.biorxiv.org/content/biorxiv/suppl/2018/09/20/423079.DC1/423079-1.pdf):
"Previously we had shown that CHG could be modelled as a mixture of Iran_N and European hunter-gatherers12.

(...)
Thus, Iran_N/CHG are seen as descendants of populations that existed in the Villabruna→Basal Eurasian cline alluded to above, but with extra Basal Eurasian ancestry (compared to Dzudzuana), and also with ENA/ANE ancestry. The extra ENA/ANE ancestry also explains the affinity between Iran/Caucasus and EHG previously proposed as part of a North/East West Eurasian interaction sphere12, which our results suggest was created by admixture of ENA/ANE ancestry on top of the Villabruna→Basal Eurasian cline."

I confess I'm not seeing this extra-BE in CHG/Iran compared to Dzudzuana. 23-25.5% BE in the former against 27.5% in the latter. Well, it's possible I'm missing something.
 
According to Lazaridis et al., CHG could be modelled as ~64.3% Dzudzuana-like plus ~30.3% ANE-like and extra ~5.4 BE, while Iran Neo is better modelled as ~57.7% Dzudzuana-like plus ~32.7% ANE-like and extra ~9.7% BE. These results would mean CHG as ~46.6 WHG-like, 30.3% ANE-like and ~23% BE, and Iran Neo as ~41.8 WHG-like, ~32.7 ANE-like and ~25.5 BE. ANF would have a similar amount of BE.
EHG Karelia is being modelled as ~66% ANE-like plus 34% WHG-like.

It's also said (https://www.biorxiv.org/content/biorxiv/suppl/2018/09/20/423079.DC1/423079-1.pdf):
"Previously we had shown that CHG could be modelled as a mixture of Iran_N and European hunter-gatherers12.

(...)
Thus, Iran_N/CHG are seen as descendants of populations that existed in the Villabruna→Basal Eurasian cline alluded to above, but with extra Basal Eurasian ancestry (compared to Dzudzuana), and also with ENA/ANE ancestry. The extra ENA/ANE ancestry also explains the affinity between Iran/Caucasus and EHG previously proposed as part of a North/East West Eurasian interaction sphere12, which our results suggest was created by admixture of ENA/ANE ancestry on top of the Villabruna→Basal Eurasian cline."

I confess I'm not seeing this extra-BE in CHG/Iran compared to Dzudzuana. 23-25.5% BE in the former against 27.5% in the latter. Well, it's possible I'm missing something.

This makes more sense than Iran_N being just Basal + ANE with some ENA in there too.
 
Shamiri: This seems like a repeat of another thread about the spread of Indo-European languages. Not one I really care to get into that much. On a personal note, I am interested in what is the best direct source of Steppe ancestry that entered the Italian mainland, as well as Sicily, Sardinia. All it means is some Iranian related ancestry came into the West via Steppe migration. The Lazaradis et al 2016 paper that I linked indicates that some Iranian-Related ancestry was part of the Steppe, notice related, it could just as easy be CHG.

"Admixture did not only occur within the Near East but also extended towards Europe. To the north, a population related to people of Chalcolithic Iran contributed about 43% of the ancestry of early Bronze Age populations of the steppe. The spread of Near Eastern ancestry into the Eurasian steppe was previously inferred without access to ancient samples, with a population related to present-day Armenians as a suggested source7,8. To the west, the early farmers of mainland Europe were descended from a population related to Neolithic North-Western Anatolians. This is consistent with an Anatolian origin of farming in Europe, but does not reject other sources, as the spatial distribution of the Anatolian/European-like farmer populations is unknown. We can rule out the hypothesis that European farmers stem directly from a population related to the ancient farmers of the southern Levant, however, because European farmers share more alleles with Anatolian Neolithic farmers than with Levantine farmers..."

I am not sure what you are now asking, it seems the goal post are being moved. I think the papers I linked answered your questions, the Iran_Neolithic seems to share genetic affinity with CHG.

I don't know how you can't see in the map that steppe ancestry and Iranian-related ancestry are two different lines, the date on the map is "2000 BC", but Lazaradis et al paper talks about people of Chalcolithic Iran (about 5000-4000 BC), this Iranian-related ancestry clearly comes through Anatolia, not the steppe. I think you know what it means but you want interpret it in another way.
 
I just searched in Google Image and found another map:

o91m_steppe.jpg


It says Anatolia and Iran plus Steppe?! But it comes from the northwest of Iran, in the west of Anatolia it is divided into two branches.
 
Iranian-related means related to NEOLITHIC Iranians, not later inhabitants of Iran.

Please show your source about it, there are some thousands years between 2000-1500 BC and Neolithic age, please also be clear, when we read about unmixed people with Iranian-related ancestry in the Middle Bronze age, who these people could be other than inhabitants of Iran?
 
Id like to see more evidence for East Eurasian in Iran_N. I also find it hard to believe that that Iran_N has nothing WHG/AHG/UHG related.

You are right. Iran Neo is not BE and ANE

Iran Neo is something like 57% Dzudzuana and the rest ANE and Basal
So it has a CWE component ( WHG like) of around 38%.
 

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