Genetic History of the Altai Breed Horses: From Ancient Times to Modernity.

This study focuses on expanding knowledge about the genetic diversity of the Altai horse native to Siberia. While studying modern horses from two Altai regions, where horses were subjected to less crossbreeding, we tested the hypothesis, formulated on the basis of morphological data, that the Altai horse is represented by two populations (Eastern and Southern) and that the Mongolian horse has a greater genetic proximity to Eastern Altai horses. Bone samples of ancient horses from different cultures of Altai were investigated to clarify the genetic history of this horse breed. As a genetic marker, we chose hypervariable region I of mitochondrial DNA. The results of the performed phylogenetic and population genetic analyses of our and previously published data confirmed the hypothesis stated above. As we found out, almost all the haplotypes of the ancient domesticated horses of Altai are widespread among modern Altai horses. The differences between the mitochondrial gene pools of the ancient horses of Altai and Mongolia are more significant than between those of modern horses of the respective regions, which is most likely due to an increase in migration processes between these regions after the Early Iron Age.

High genetic diversity of ancient horses from the Ukok Plateau.

A growing number of researchers studying horse domestication come to a conclusion that this process happened in multiple locations and involved multiple wild maternal lines. The most promising approach to address this problem involves mitochondrial haplotype comparison of wild and domestic horses from various locations coupled with studies of possible migration routes of the ancient shepherds. Here, we sequenced complete mitochondrial genomes of six horses from burials of the Ukok plateau (Russia, Altai Mountains) dated from 2.7 to 1.4 thousand years before present and a single late Pleistocene wild horse from the neighboring region (Denisova cave). Sequencing data indicates that the wild horse belongs to an extinct pre-domestication lineage. Integration of the domestic horse data with known Eurasian haplotypes of a similar age revealed two distinct groups: the first one widely distributed in Europe and presumably imported to Altai, and the second one specific for Altai Mountains and surrounding area.

Maternal genetic features of the Iron Age Tagar population from Southern Siberia (1st millennium BC).

Early nomads in the Eurasian steppes since the beginning of the 1st millennium BC played a key role in the formation of the cultural and genetic landscape of populations of a significant part of Eurasia, from Eastern Europe to Eastern Central Asia. Numerous archaeological cultures associated with early nomads have been discovered throughout the Eurasian steppe belt. The Tagar archaeological culture existed in the Minusinsk basin (Sayan Mountains, Southern Siberia, Russia) in the northeastern periphery of the Eurasian steppe belt from the 8th to 1st century BC during the pre-Scythian, Scythian, and Early Xiongnu-Sarmatian periods. In this study, we evaluated mtDNA diversity in the Tagar population based on representative series (N = 79) belonging to all chronological stages of the culture. The Tagar population had a mixed mtDNA pool dominated by Western Eurasian haplogroups and subgroups (H, HV6, HV*, I, K, T, U2e, U4, U5a, and U*) and, to a lesser degree, Eastern Eurasian haplogroups (A*, A8, C*, C5, D, G2a, and F1b). The Tagar population showed a similar mtDNA pool structure to those of other Iron Age populations representing the "Scythian World." We observed particularly high similarity between the Tagar and Classic Scythians from the North Pontic region. Our results support the assumption that genetic components introduced by Bronze Age migrants from Western Eurasia contributed to the formation of the genetic composition of Scythian period populations in Southern Siberia. Another important component of the Tagar mtDNA pool was autochthonous East Eurasian lineages, some of which (A8 and C4a2a) are potential markers of the westward genetic influence of the eastern populations of the Scythian period. Our results suggest a genetic continuity (at least partial) between the Early, Middle, and Late Tagar populations.

Ancestry and demography and descendants of Iron Age nomads of the Eurasian Steppe.

During the 1st millennium before the Common Era (BCE), nomadic tribes associated with the Iron Age Scythian culture spread over the Eurasian Steppe, covering a territory of more than 3,500 km in breadth. To understand the demographic processes behind the spread of the Scythian culture, we analysed genomic data from eight individuals and a mitochondrial dataset of 96 individuals originating in eastern and western parts of the Eurasian Steppe. Genomic inference reveals that Scythians in the east and the west of the steppe zone can best be described as a mixture of Yamnaya-related ancestry and an East Asian component. Demographic modelling suggests independent origins for eastern and western groups with ongoing gene-flow between them, plausibly explaining the striking uniformity of their material culture. We also find evidence that significant gene-flow from east to west Eurasia must have occurred early during the Iron Age.

MtDNA Haplogroup A10 Lineages in Bronze Age Samples Suggest That Ancient Autochthonous Human Groups Contributed to the Specificity of the Indigenous West Siberian Population.

BACKGROUND: The craniometric specificity of the indigenous West Siberian human populations cannot be completely explained by the genetic interactions of the western and eastern Eurasian groups recorded in the archaeology of the area from the beginning of the 2nd millennium BC. Anthropologists have proposed another probable explanation: contribution to the genetic structure of West Siberian indigenous populations by ancient human groups, which separated from western and eastern Eurasian populations before the final formation of their phenotypic and genetic features and evolved independently in the region over a long period of time. This hypothesis remains untested. From the genetic point of view, it could be confirmed by the presence in the gene pool of indigenous populations of autochthonous components that evolved in the region over long time periods. The detection of such components, particularly in the mtDNA gene pool, is crucial for further clarification of early regional genetic history. RESULTS AND CONCLUSION: We present the results of analysis of mtDNA samples (n = 10) belonging to the A10 haplogroup, from Bronze Age populations of West Siberian forest-steppe (V-I millennium BC), that were identified in a screening study of a large diachronic sample (n = 96). A10 lineages, which are very rare in modern Eurasian populations, were found in all the Bronze Age groups under study. Data on the A10 lineages' phylogeny and phylogeography in ancient West Siberian and modern Eurasian populations suggest that A10 haplogroup underwent a long-term evolution in West Siberia or arose there autochthonously; thus, the presence of A10 lineages indicates the possible contribution of early autochthonous human groups to the genetic specificity of modern populations, in addition to contributions of later interactions of western and eastern Eurasian populations.