Maternal DNA lineages at the gate of Europe in the 10th century AD

Abstract

Given the paucity of archaeogenetic data available for medieval European populations in comparison to other historical periods, the genetic landscape of this age appears as a puzzle of dispersed, small, known pieces. In particular, Southeastern Europe has been scarcely investigated to date. In this paper, we report the study of mitochondrial DNA in 10th century AD human samples from Capidava necropolis, located in Dobruja (Southeastern Romania, Southeastern Europe). This geographical region is particularly interesting because of the extensive population flux following diverse migration routes, and the complex interactions between distinct population groups during the medieval period. We successfully amplified and typed the mitochondrial control region of 10 individuals. For five of them, we also reconstructed the complete mitochondrial genomes using hybridization-based DNA capture combined with Next Generation Sequencing. We have portrayed the genetic structure of the Capidava medieval population, represented by 10 individuals displaying 8 haplotypes (U5a1c2a, V1a, R0a2’3, H1, U3a, N9a9, H5e1a1, and H13a1a3). Remarkable for this site is the presence of both Central Asiatic (N9a) and common European mtDNA haplotypes, establishing Capidava as a point of convergence between East and West. The distribution of mtDNA lineages in the necropolis highlighted the existence of two groups of two individuals with close maternal relationships as they share the same haplotypes. We also sketch, using comparative statistical and population genetic analyses, the genetic relationships between the investigated dataset and other medieval and modern Eurasian populations.

Mitochondrial ancestry of medieval individuals carelessly interred in a multiple burial from southeastern Romania

“…The analysis and interpretation of genome-wide aDNA data from more than 200 individuals inhabiting southeastern Europe between 12,000 and 500 BC, showed that this geographical region “served as a genetic contact zone between east and west over thousands of years 6 ”. This pattern was also observed in a small medieval group of individuals from southeastern Romania (Dobruja) 7 . The genetic connections to Central Asia were reflected by the presence of the N9a haplotype in 2 out of 10 successfully analyzed samples 7 .…”

“…This pattern was also observed in a small medieval group of individuals from southeastern Romania (Dobruja) 7 . The genetic connections to Central Asia were reflected by the presence of the N9a haplotype in 2 out of 10 successfully analyzed samples 7 . Evidence from present-day maternal haplogroup diversity in the historical provinces of Romania showed that the Asian influence in Dobruja is greater than in the other regions, and suggested that the Carpathian Arch might have had an influential role in migration patterns 8 .…”

“…Previous radiocarbon dating is available for Cap-M4 (880–990 cal. AD) an individual buried according to Christian funerary custom in terrace B of the necropolis 7,12 .…”

“…Pairwise genetic distances were calculated based on the complete mitochondrial genomes of 18 ancient Eurasian populations, including the medieval Capidava group (Supplementary Table S5). Due to the fact that our investigated population is small (six samples) we grouped it together with four of the formerly published medieval samples from this necropolis 7 . The medieval population from Capidava showed the lowest distances from four ancient populations: Bronze Age population of the Balkan Peninsula (Balkans_BA) (F ST = −0.0348), Srubnaya (SRU) (F ST = −0.02367), Poltavka-Potapovka (PBA) (F ST = −0.01677), and Hungarian Conquerors (HUN_Conq) (F ST = −0.01325); these values were not significant (p > 0.05).…”

A genetic perspective on Longobard-Era migrations

“…PCA based on haplogroup frequencies was conducted employing the function fviz_pca_biplot from the library factoextra [19] in R 3.4.0 [20]. The haplogroups frequencies of complete mitochondrial genomes from ancient populations (from Neolithic to medieval times) were taken from [21][22][23][24][25][26][27][28][29][30][31][32]. For a comparison with modern European variation, we used the data published by ref.…”