mtDNAwiki on “Steppe folk” mtDNA and Indo-Iranian origins

Fascinating stuff from Samuel at mtDNAwiki. Emphasis is mine:

Steppe folk were people who resided in what are today Southern Russia and Eastern Ukraine between 6,000 and 4,000 years ago. They were very different from the Anatolian farmers I discussed earlier.
Ancient DNA shows that, between 3000 and 2000 BC, Steppe folk migrated en masse into Northern Europe, Central Asia and Siberia. Shortly afterwards, Steppe folk settled in South Europe, South Asia (India, Afghanistan, etc.), and Iran.
They contributed huge chunks of ancestry to countless modern ethnic groups. Modern-day Europeans are for the most part a two-way mixture between Steppe folk and European Neolithic farmers (who were mostly of Anatolian origin).
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As much as 33% of Tajik mtDNA really does derive from Eneolithic/Bronze Age Eastern Europe. No doubt about it. Yes, Tajiks are an exception, because they have a lot more Steppe mtDNA than essentially all other South Central Asians. However, significant frequencies of Steppe mtDNA exist in every population in this region. For example, the mtDNA in the Kalasha, a small ethnic group from the Hindu Kush, is mostly made up of founder effects involving Steppe mt-HGs U4a1, U4b1a4, U2e1h, and J2b1a. Each of these haplogroups has been found in remains from Eneolithic/Bronze Age Eastern Europe.
Typical European haplogroups such as U5a1a1, H2a1, T1a1, H5a1, H6a1, J1b1a1, J2b1a, H7b, etc. consistently pop up in every South Central Asian population. Realistically, none of these haplogroups are more than 10,000 years old. Indeed, all of them are likely to be less than 7,000 years old. The European-related mtDNA in South Central Asia isn’t derived from distant, Paleolithic shared ancestry between Europeans and Asians. It’s recent stuff from the Steppe.
For over a decade Y-haplogroup R1a-M417 perplexed many geneticists because it was the most common Y-haplogroup in two geographically very distant peoples; Balto-Slavs of Eastern Europe and Indo-Aryans of South Asia. But thanks to ancient DNA, it has now been confirmed that R1a-M417 is an European Steppe lineage which expanded both west and east from the Pontic-Caspian Steppe between 4,600 and 3,500 years ago.
Interestingly, I’ve found mtDNA haplogroups which correlate very well with R1a-M417; meaning that they either exist in South Asians & Eastern Europeans, or in South Asians & ancient Central and Eastern Europeans rich in R1a-M417, such as the Corded Ware and Srubnaya peoples.
J1c1b1a: Russia, Ukraine, Hungary, Romania, Denmark, UK, Spain, Tajik, India. Srubnaya (R1a-Z93), Corded Ware (R1a-M417).
H2a1a: Russia, Hungary=2, Finland, Britain, Ireland, France, Pathan, Tajik=16, Turkey, Siberia. Eneolithic Ukraine (R1a-M417), Bronze age Scotland, Unetice.
H5e1: Russia=2, Hungary, Greece, Tajik=3.
T1a1b: Russia=4, Poland=3, Hungary=2, Iran=2, Turkey, Tajik=4, India. Bronze age Latvia, Sycthian=2.
N1a1a1a1: Estonia=3, Finland=2, Italy, Turkmen, India=2. Sintashta, Sycthian, Sarmatian.
K2a5: Estonia, Ireland, Iran, Sindhi, Pathan, India. Corded Ware Germany, Corded Ware Sweden.
U4b2: Russia, Ukraine, Sweden, Spain, Burosho, Tajik, India.
U4b1a4: Kalash, Tajik, Iran, Siberia=3. Catacomb, Sycthian.
U2e1h: Kalash=3, Tajik=8, Siberia, Italy. Sintashta, Potapovka
The most important mt-HGs here are U2e1h, H2a1a, U4b1a4, T1a1b, and N1a1a1a1. They directly link modern Indo-Iranian speakers in Asia with Eneolithic/Bronze age Eastern Europeans generally considered by historical linguists and archaeologists to be Proto-Indo-European- or Proto-Indo-Iranian-speakers (i.e. Sintashta and Potapovka).
When I put all of this data together, and saw the undeniable links between modern-day Indo-Iranian speakers and Eneolithic/Bronze Age Eastern Europeans, I was amazed. The results confirmed to me, beyond any doubt, that the ancient migrations from the western Steppe deep into Asia long hypothesized by historical linguists and archaeologists did happen. Indo-Iranian languages really did originate in Eastern Europe, probably in what is now Ukraine, then took the long journey all the way to the Indian Subcontinent.
Case in point: ancient DNA sample I6561. That’s his lab ID, but he’s a man who died in what is now Ukraine ~5,500 years ago. He belonged to Y-HG R1a-M417 and mt-HG H2a1a. Today H2a1a is most common in the Tajik people of South Central Asia. The most common Y-HG in Tajiks, and many of their neighbors, such as Pashtuns, Kalasha, northern Indians, etc. is R1a-M417.
All of the evidence suggests that Mr. I6561 belonged to a PIE community whose descendants would go on to settle lands that stretch all the way from modern-day Norway to India. His people are important founders of countless modern ethnic groups; Russians, Czechs, Tajiks, Pashtuns, Indians, and so on. Oh yeah, and also the ancient Scythians, who dominated much of Asia around 500 BC, derived directly from his people. Pretty amazing.
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It’s been known for a while, via archaeological data, that Steppe folk traded with these farmers. But now, thanks to ancient DNA, it’s clear that they exchanged more than just goods. Enneolithic and Bronze Age genomes from what are now Ukraine, Romania, and Bulgaria show that the Steppe and farmer folks began mixing by at least 4400 BC.
Hence, when Steppe folk expanded both west and east, they took with them at least a little Anatolian admixture. This is also true for the Steppe folk who went to South Asia. Several of the mt-HGs that I labeled “Steppe” are in fact Anatolian mt-HGs that the Steppe folk acquired through admixture with farmer peoples before their mass migrations. These include mt-HGs H1b1, H5a1, H7b, J1c1b1a, J2b1a, N1a1a1a1, K1b1a1, HV6, and HV9.
It’s often said, in scientific literature as well as on various genetic blogs and forums, that the Steppe folk who moved into South Asia didn’t harbor any Anatolian ancestry. But my mtDNA data easily debunks this claim. South Asians do indeed carry some Anatolian-derived mtDNA which they, in all likelihood, acquired from their Steppe ancestors.

See also…
Another look at the genetic structure of Yamnaya
Ancient herders from the Pontic-Caspian steppe crashed into India: no ifs or buts
Descendants of ancient European (fair?) maidens in Central Asia’s highlands
Late PIE ground zero now obvious; location of PIE homeland still uncertain, but…

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