An understanding of the origin of R-M269 is relevant for the question of population replacement in the Neolithic Revolution. R-M269 had formerly been dated to the Upper Paleolithic, but by about 2010 it had become clear that it arose near the beginning of the Neolithic Revolution, about 10,000 years ago. The R-L23 (R-Z2103) subclade has been found to be prevalent in ancient DNA associated with the Yamna culture. David Anthony considers the Yamna culture to be the Indo-European Urheimat.
No clear consensus has been achieved as to whether it arose within Europe or in Western Asia. Balaresque et al. (2010) based on the pattern of Y-STR diversity argued for a single source in the Near East and introduction to Europe via Anatolia in the Neolithic Revolution. In this scenario, Mesolithic hunter-gatherers in Europe would have been nearly replaced by the incoming farmers. By contrast, Busby et al. (2012) could not confirm the results of Balaresque et al. (2010) and could not make credible estimates of the age of R-M269 based on Y-STR diversity.
By contrast, the subclade R-P311 appears to have originated after the beginning of the Neolithic Revolution in Europe, and is substantially confined to Western Europe in modern populations. R-P311 is absent from Neolithic-era ancient DNA found in Western Europe, strongly suggesting that its current distribution is due to population movements within Europe taking place after the end of the Neolithic. The three major subclades of P311 are U106 (S21), L21 (M529, S145), and U152 (S28). These show a clear articulation within Western Europe, with centers in the Low Countries, the British Isles and the Alps, respectively.
According to Jones et al. (2015) and Haak et al. (2015), autosomic tests indicate that the Yamnaya people were the result of admixture between two different hunter-gatherer populations: distinctive “Eastern European hunter-gatherers” with high affinity to the Mal’ta–Buret’ culture or other, closely related people from Siberia[ and a population of “Caucasus hunter-gatherers” who probably arrived from the Caucasus. Each of those two populations contributed about half the Yamnaya DNA. According to co-author Andrea Manica of the University of Cambridge:
The question of where the Yamnaya come from has been something of a mystery up to now we can now answer that, as we’ve found that their genetic make-up is a mix of Eastern European hunter-gatherers and a population from this pocket of Caucasus hunter-gatherers who weathered much of the last Ice Age in apparent isolation.
Several genetic studies performed since 2015 have given support to the Kurgan theory of Marija Gimbutas regarding the Indo-European Urheimat – that Indo-European languages spread throughout Europe from the Eurasian steppes and that the Yamnaya culture were Proto-Indo-Europeans. According to those studies, haplogroups R1b and R1a, now the most common in Europe (with R1a also being common in South Asia), would have expanded from the Pontic–Caspian steppes, along with the Indo-European languages. They also detected an autosomal component present in modern Europeans which was not present in Neolithic Europeans, which would have been introduced with paternal lineages R1b and R1a, as well as Indo-European languages in the Bronze Age.