From recent studies
The fact that the Golden elite individual from the Varna culture belongs to T, and the fact that the earlier Starčevo–Körös–Criș culture individual from the same Bulgarian region belongs to T, means that the ruling group of the Neolithic Revolution could be related to T.
Also, the gold found among the Varna culture shows that metallurgy was introduced into the neighbouring Steppe regions by the people of the Varna culture. And the early farmers of the Starčevo–Körös–Criș culture were probably the ones that brought farming to the Steppe.
Two quotes from David Anthony's papers:
Quote 1:
"Ornaments of Balkan copper, exotic ornamental shells (Glycemeris, Antalis), long lamellar flint blades, polished stone maces, and perhaps people and animals were exchanged across the Pontic–Caspian steppes from Varna to Khvalynsk and Svobodnoe between 4500-4200 BC."
Quote 2:
"At the cemetery of Khvalynsk on the middle Volga, dated about 4700 bc, 320 copper ornaments were found in 201 graves. Some objects were made or repaired locally, but most were made of Bulgarian copper, and a handful (rings and spiral bracelets) were made in the same way as the copper ornaments found at Varna, and probably were imported from Bulgaria."
Before farming was found in the steppe regions, the people of the steppe consisted of different distinct unrelated cultures, totally different from the later Khvalynsk / Sredny Stog culture. So, it is obvious that the ancestors of the Varna golden elite individual were involved in the formation of this Eneolithic steppe civilization. The people of the Neolithic Revolution brought their culture to the natives of the Steppe during the Eneolithic period, and mixed with each other in time.
And I think that the arrival of the ancestors of the Steppe Maykop individual IV3002 from the Ipatovo kurgan in the steppe region is probably related to these mixing events described above.
Sample IV3002
[h=3]Ipatovo 3 ( 5400 yBP - Early Bronze Age ) Early Steppe Maykop Culture[/h]
IV3002 ( 5383 ± 64 yBP )
Kurgan: 2
Phase: 1st
Grave: 187 ( Founding grave of the entire mound )
Other dates: 5058 ± 223 yBP / 5328 ± 251 yBP / 4630 ± 50 yBP (radiocarbon)
Y-DNA:
T1-CTS6004 (xT1a1a-CTS484, T1a1b-Y6031, T1a2b-FGC37316) Probably:
T1a2a-Y8614
mtDNA: X1'2'3
Age at Death: 35-45