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

<div><p>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 10^th 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.</p></div

MDS plot of Romanian medieval population and modern Eurasian populations.

<p>Stress value is 0.1323 and non-metric fit (R²) is 0.982, values that highlight a good fit between the two-dimensional graph and the original distance matrix. The linearized Slatkin F_ST values and population information are presented in the <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0193578#pone.0193578.s013" target="_blank">S9 Table</a>.</p

PCA plot of the first two components (34.82% of variance) of medieval populations.

<p>The PCA based on mtDNA haplogroup frequencies of the 15 medieval populations shows a roughly clustering of the ancient populations from Romania (ROU-med) and medieval Cumanians from Hungary (HUN-Cum). The other medieval populations from Southern Europe are clustered together, as are those from the North of Europe. The abbreviations, references and haplogroup frequencies are presented in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0193578#pone.0193578.s009" target="_blank">S5 Table</a>.</p

Levelplot of the linearized Slatkin population differentiation (F_ST) values and significant p values.

<p>Lower left corner: significant p values (< 0.05) are indicated in green. Upper right corner: larger Slatkin F_ST values indicating greater genetic distances are marked by dark red shades. The exact F_ST and p values and population information are indicated in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0193578#pone.0193578.s010" target="_blank">S6 Table</a>.</p

PCA of the investigated medieval and present-day populations.

<p>The PCA is based on mtDNA haplogroup frequencies of the medieval population from Romania and 35 modern populations from Eurasia and shows PC1 and PC2. The haplogroup frequencies and population information are listed in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0193578#pone.0193578.s012" target="_blank">S8 Table</a>.</p

Additional file 1: of Dual polarization of human alveolar macrophages progressively increases with smoking and COPD severity

Immunohistochemical and confocal analysis of alveolar macrophage polarization: Methods and Results. (DOCX 93 kb