In 2019 Wang et al. published three ancient samples from north Caucasian foothill steppe region. They got the label Steppe Eneolithic. The term "Steppe" is usually used in genetic papers to label DNA related or similar to Yamnaya genetic profile.
Those Steppe Eneolithic samples were remarkable because not only they have the genetic profile similar to Yamnaya but were also older than it. Back then they didn't get the attention they deserved because they were not from a famous culture. In 2024 Lazaridis et al. proposed a new name for them the Caucasus - Lower Volga cline and added new similar samples. Genetic calculations showed that genome wide Yamnaya got most of their ancestry from this CLV folks. Despite this advance the two most important Y markers were still not securely linked to this CLV population. The R1b-M269 and R1a-M417 which had a large expansion all over Eurasia spreading the Indo-European languages.
Ghalichi et al. 2024 filled this gap. Two new cases of R1b-M269 were found before the Yamnaya near North of Caucasus region. They had similar to other Steppe Eneolithic groups ancestry dated at around 3800BC. It's worth to note that there was another older M269 sample (I33307) from Kalmykia dated around 3700 but it's genetic profile is identic to Core Yamnaya raising the suspicion that it is younger than the radiocarbon dates show. Lazaridis et al. labeled this sample as Russia_Caspianinland_EBA_Yamnaya group that is why I didn't included it in this list of Steppe Eneolithic Y DNA (4700-3000BC. See the map for the geographic area)
R1b-V1636 -----9
R1b-M269. -----2
R1a. -----1
I2-L699. ------1
J2a ------1
J2b2a. ------1
Besides those cases another possible old R1b-M269 (around 4500BC) was found in Bulgaria in Varna culture burial. It's autosomes showed an obvious Steppe Eneolithic related ancestry. Which means that it was not related to local Neolithic farmers and was a migrant from the Caucasus Lower Volga region. Varna was a peculiar culture with highly hierarchical organization. Large number of gold items were found from Varna culture graves.
Another important finding in the Steppe Eneolithic context is off course the J2b2a-L283. Its autosomes were more Caucasus shifted which is understandable. But overall, it was part of that emerging kurgan Eneolithic groups from which the Yamnaya and Corded Ware Culture will stem few centuries later.
We haven't yet found the R1a-M417 in the forementioned context. But given that one of oldest R1a-M198 (close to M417) was found in Middle Volga region we can assume that M417 will be found in Steppe Eneolithic / CLV region also. Currently one of oldest R1a-M417 is from Yamnaya layer in Balkans.
Based on this data I will restate my scepticism about the possibility that Yamnaya descend from Sredny Stog located in Ukraine expressed on some boards. Highest diversity of Z2103+ and negative to Z2106 is found in Near East which means that the region from which Z2103 started its expansion must be close to Caucasus. More ancient DNA will hopefully solve this question also.
PS. I didn't include in that Eneolithic Y DNA list samples from Steppe Maykop who have a different Central Asian origin. Also, one of V1636 is dated at 2800BC which is later than the 3000BC. But its autosomes shows that it was from preceding period and not from Core Yamnaya.
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