NEW YORK – New genetic analyses of ancient DNA support the notion that members of an elite population group that inhabited the Carpathian Basin in Southeast Europe from the late 6th to early 9th century carried ancestry originating from long-distance migrations into the region from the East Asian Steppe.
Genetic data generated from dozens of ancient samples in the region "allow us to confidently conclude that an outstanding genetic variability existed in the early Medieval Carpathian Basin, covering almost the entire genetic variation of present-day Eurasia and providing clear evidence of long-distance trans-Eurasian migrations," senior and co-corresponding author Johannes Krause, an archaeogenetics researcher at the Max Planck Institute for Evolutionary Anthropology, and his colleagues wrote in a paper published in Cell on Friday.
Using in-solution target enrichment and sequencing, investigators from Max Planck, the Institute of Archaeogenomics in Hungary, and elsewhere profiled around 1.24 million SNPs in 66 ancient samples from burial sites in the Carpathian Basin, which spans present-day Hungary, Slovakia, Poland, Ukraine, and other central European sites. The set included representatives from populations found in the region before and after the rise of a "khagan" leader-ruled Avar empire with Central Eurasian steppe origins that ruled the region for hundreds of years.
"The Byzantine texts agree that their move had been triggered by the rise of the first Turkic khaganate in the 550s, centered in what is now Mongolia, when Turks destroyed an empire called Rouran by its Chinese neighbors," the authors explained. "However, the texts do not agree on who these Avars were, or where exactly they came from."
With genome-wide SNP data for 18 pre-Avar and 48 Avar individuals, the team saw pronounced Northeast Asian ancestry in the Avar elite representatives from the Carpathian Basin, consistent with a speedy, long-distance migration into the region almost 1,500 years ago. In particular, early Avar individuals had genetic features that resembled those in an already available Rouran genome from the Mongolian Steppe.
Even so, the researchers noted that population dynamics continued shifting at the Carpathian Basin sites they looked at during early, middle, and late points in the Avar empire, which was replaced by the Franks more than 1,200 years ago.
Although Eurasian ancestry remained robust in the elite Avar individuals across the 200 years of their rule, for example, the sequence data provided a look at the genetic variation that existed in the region. It also uncovered a potential influx of western Eurasian individuals and late Avar period ancestry, hinting at additional Central Asian migrations or at greater-than-usual diversity in the original migrants.
Together, the findings "indicate the emergence of a genetically heterogeneous local elite stratum under the rule of the immigrant Avar elite population," the authors wrote. "Similarly, the more western genetic profile of non-elite, early- and late-Avar period individuals, as far as represented in the present study, shows a stronger connection with the pre-Avar population of the Carpathian Basin."