Vestiges of an Ancient Border in the Contemporary Genetic Diversity of North-Eastern Europe

It has previously been demonstrated that the advance of the Neolithic Revolution from the Near East through Europe was decelerated in the northernmost confines of the continent, possibly as a result of space and resource competition with lingering Mesolithic populations. Finland was among the last domains to adopt a farming lifestyle, and is characterized by substructuring in the form of a distinct genetic border dividing the northeastern and southwestern regions of the country. To explore the origins of this divergence, the geographical patterns of mitochondrial and Y-chromosomal haplogroups of Neolithic and Mesolithic ancestry were assessed in Finnish populations. The distribution of these uniparental markers revealed a northeastern bias for hunter-gatherer haplogroups, while haplogroups associated with the farming lifestyle clustered in the southwest. In addition, a correlation could be observed between more ancient mitochondrial haplogroup age and eastern concentration. These results coupled with prior archeological evidence suggest the genetic northeast/southwest division observed in contemporary Finland represents an ancient vestigial border between Mesolithic and Neolithic populations undetectable in most other regions of Europe.Peer reviewe

Logistic regression estimates representing the difference in haplogroup frequencies between the SW & NE subpopulations.

<p>Above X-axis: SW dominance, below: NE dominance. The results are shown for division (cf. Fig 2) that maximized the difference. Error bars denote standard deviation, statistical significance is marked with stars. No statistically significant values were obtained in randomized, non-continuous divisions.</p

Spatial patterns in different marker classes and in archaeological evidence for Combed Ware Culture in Finland.

<p>A: Division maximizing Y-STR haplotype differences, and frequencies of the main Y-haplogroups in Finland. B: Division maximizing the difference between Hunter-Gatherer (H-G: hgs U & V) and Farmer (F: hgs H, T, J & K) mtDNA haplogroups and their frequencies. C: The extent of Corded-Ware Culture (CWC; data from <a href="http://www.nba.fi" target="_blank">www.nba.fi</a>) in Finland, and the approximate location of the first political border between Sweden and Novgorod (AD 1323; hatched blue line).</p

Bayesian Skyline Plots for mtDNA haplogroups H and U in Finland, with European reference data from Fu et al. 2012.

<p>The hatched lines denote 95% confidence intervals. A: MtDNA haplogroups H (red) and U (blue) in Finland. B: Haplogroup H in Finland (red) and in Europe (grey). C: Haplogroup U in Finland (blue) and in Europe (grey).</p

The strength of NE bias for the main haplogroups plotted against the difference of haplogroup ages in Near Eastern and European populations estimated in (Richards, et al. 2000).

<p>Haplogroups with older estimated ages in Europe than in Near East show stronger eastern bias in Finland, and vice versa.</p

Map of Northern Europe with Finland and the different subpopulations analyzed.

<p>Map of Northern Europe with Finland and the different subpopulations analyzed.</p