But, from the Middle Neolithic onwards, DNA patterns more closely resembled those of people living in the area today, pointing to a major - and previously unrecognised - population upheaval around 4,000 BC.Neolithic mitochondrial haplogroup H genomes and the genetic origins of Europeans
Co-author Prof Alan Cooper, from the University of Adelaide in Australia, said: "What is intriguing is that the genetic markers of this first pan-European culture, which was clearly very successful, were then suddenly replaced around 4,500 years ago, and we don't know why.
"Something major happened, and the hunt is now on to find out what that was." [. . .]
A significant contribution appears to have been made in the Late Neolithic, by populations linked to the so-called Bell Beaker archaeological culture. Sub-types of haplogroup H that are common today first appear with the Beaker people and the overall percentage of individuals belonging to the H clan jumps sharply at this time.
The origins of the "Beaker folk" are the subject of much debate. Despite having been excavated from the Mittelelbe Saale region of Germany, the Beaker individuals in this study showed close genetic similarities with people from modern Spain and Portugal.
Other remains belonging to the Late Neolithic Unetice culture attest to links with populations further east.
"We have established that the genetic foundations for modern Europe were only established in the Mid-Neolithic, after this major genetic transition around 4000 years ago," said co-author Dr Wolfgang Haak.
"This genetic diversity was then modified further by a series of incoming and expanding cultures from Iberia and Eastern Europe through the Late Neolithic."
Haplogroup H dominates present-day Western European mitochondrial DNA variability (>40%), yet was less common (~19%) among Early Neolithic farmers (~5450 BC) and virtually absent in Mesolithic hunter-gatherers. Here we investigate this major component of the maternal population history of modern Europeans and sequence 39 complete haplogroup H mitochondrial genomes from ancient human remains. We then compare this ‘real-time’ genetic data with cultural changes taking place between the Early Neolithic (~5450 BC) and Bronze Age (~2200 BC) in Central Europe. Our results reveal that the current diversity and distribution of haplogroup H were largely established by the Mid Neolithic (~4000 BC), but with substantial genetic contributions from subsequent pan-European cultures such as the Bell Beakers expanding out of Iberia in the Late Neolithic (~2800 BC). Dated haplogroup H genomes allow us to reconstruct the recent evolutionary history of haplogroup H and reveal a mutation rate 45% higher than current estimates for human mitochondria.