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Distribution maps of autosomal admixtures in Europe, the Middle East and North Africa

Introduction

The following maps were created based on the data from the Dodecad Project and Eurogenes.

The map of Early European Farmer (EEF) ancestry uses Eurogenes's EEF-WHG-ANE test. The Gedrosian and Caucasian maps are based on the Dodecad's K=12b admixtures. The Red Sea map uses the K=10a admixtures. All the other maps were are based on the Dodecad's K=12 admixtures.

Note that the 'West European' admixture was renamed 'Northwest European' on Eupedia, as it fits better the overall distribution of this admixture. The African admixture was computed by adding up the Northwest African, East African, Neo African and Paleo African components, which were too minor in Europe on their own. The East Asian admixture combines Northeast Asia and Southeast Asia.

Please be aware that the maps are very approximate due to the scantity of regional data available, and the complete lack of data for some countries at present (including the Czech Republic, Slovakia, Slovenia, Bosnia-Herzegovina, Serbia, and Macedonia).

Contents

Early European Farmer (EEF) admixture

This map compares the genes of modern people to the DNA of a Neolithic individual from Stuttgart in Germany, who lived 7500 years ago. The Neolithic sample was tested by Lazaridis et al. (2014). It is supposed to reflect the percentage of similarity with Neolithic farmers who colonised Europe from the Near East. The closest modern populations are the Ashkenazi Jews (93%), Maltese (93%) and Sicilians (90%).

Distribution of the Early European Farmer (EEF) in Europe, the Middle East and North Africa

Distribution of the Early European Farmer (EEF) admixture in and around Europe

Northwest European admixture

The Northwest European admixture appears to be strongly Indo-European and correlates particularly well with the haplogroup R1b-L11, representing essentially the Italic, Celtic and Germanic branches of the Indo-Europeans. In eastern Europe, the Northwest European admixture once merged with the East European admixture represents the Baltic and Slavic branches of the Indo-Europeans.

Distribution of the Northwest European admixture in Europe, the Middle East and North Africa

Distribution of the Northwest European admixture in and around Europe

East European admixture

Note the resemblance with the distribution of Y-DNA haplogroup R1a.

Distribution of the East European admixture in Europe, the Middle East and North Africa

Distribution of the East European admixture in and around Europe

Mediterranean admixture

Distribution of the Mediterranean admixture in Europe, the Middle East and North Africa

Distribution of the Mediterranean admixture in and around Europe

West Asian admixture

Note the resemblance with the distribution of Y-DNA haplogroup J2.

Distribution of the West Asian admixture in Europe, the Middle East and North Africa

Distribution of the West Asian admixture in and around Europe

       

Caucasian admixture

The Caucasian admixture was probably brought to Europe by various West Asian people during the Neolithic, Chalcolithic and Bronze Age.

Distribution of the Caucasian admixture in Europe, the Middle East and North Africa

Distribution of the Caucasian admixture in and around Europe

Gedrosian admixture

The Gedrosian admixture was probably brought to Europe by Y-DNA haplogroup R1b, although its distribution in Asia correlates more with Y-haplogroups G, J2 and L.

Distribution of the Gedrosian admixture in Europe, the Middle East and North Africa

Distribution of the Gedrosian admixture in and around Europe

Southwest Asian admixture

Note the resemblance with the distribution of Y-DNA haplogroup J1.

Distribution of the Southwest Asian admixture in Europe, the Middle East and North Africa

Distribution of the Southwest Asian admixture in and around Europe

Red Sea admixture

The Red Sea admixture peaks in Ethiopia and Somalia, the region of origin of Y-DNA haplogroup E1b1b, to which its distribution is closely linked, except in northwestern Europe.

Distribution of the Red Sea (Horn of Africa) admixture in Europe, the Middle East and North Africa

Distribution of the Red Sea African admixture in and around Europe

African admixture

This is essentially a Northwest African admixture. Note the resemblance with the distribution of Y-DNA haplogroup E-M81.

Distribution of the African admixture in Europe, the Middle East and North Africa

Distribution of the African admixture in and around Europe

East Asian admixture

Distribution of the East Asian admixture in Europe and the Middle East

Distribution of the East Asian admixture in and around Europe

Comparing maps of autosomal DNA with Y-DNA haplogroups

It is tempting to make analogies between the distribution of autosomal admixtures and that of Y-DNA haplogroups. While both of them represent the migrations of certain populations and may roughly correspond to the same source populations, it is essential to understand that any correspondance has its limits for a number of reasons.

  1. Whereas Y-chromosomal lineages can be organised in a neat genealogical tree ('phylogenetic tree' is the technical word), it is much harder for autosomes due to the fact that they get mixed up ('recombined') at every generation with other autosomes. To trace back the origins of a population, the idea is to check which modern populations share the same unique mutations spread out on all 22 pairs of non-sex chromosomes. That's why they are referred to as "admixtures". The names for each admixture are arbitrary and do not necessarily refer to the source population who spread those genes, but usually the geographic region where it is most common today. For example, the Southwest Asian admixture got its name because this set of mutations is most common in the Arabian peninsula nowadays. But Arabic people descend from nomadic herders who lived around the Zagros and Taurus mountains, around northern Mesopotamia, during the Neolithic period. This is also the case of Y-haplogroup J1, with which the Southwest Asian admixture best correlates. In other words, the so-called Southwest Asian admixture found in a European individual may never have come from Southwest Asia (Arabic peninsula) at all, but rather from Anatolia.

  2. Any admixture can be broken down into a number of more specific admixtures, splitting populations that may otherwise have looked closely related. The Northwest European admixture almost certainly comprises DNA markers from two completely different source populations. That is why it is found at high frequencies among the Finns, the Irish and the Iberians, three populations that do not share a lot in common history or phenotypes. It is also found at lower but still substantial frequencies in the Chuvash people (22%) from the Volga region, and the Adygey people (16%) from the North Caucasus, and the Uyghur people (10%) from Northwest China. In all likelihood, the Northwest European component is composed of markers belonging to the Paleolithic population of northern and western Europe (haplogroup I), as well as an Indo-European element (haplogroup R1b) that originated in the Black Sea region.

  3. The way Y chromosomes and autosomes are transmitted is very different. Y chromosomes are strictly inherited from fathers to sons and never recombine, while autosomes are inherited at 50% through each parent. This will inevitably affect their respective geographic distribution since it is known that in most European societies through the ages male children (usually the eldest sons) were the ones who inherited the land, house, farm or even castle from their parents, and therefore stayed from generation to generation at the same place. Women, on the contrary, were married off to men from neighbouring tribes, villages or towns. They were sometimes sent quite far away, especially in royal and noble families that frequently used daughters to seal alliances with other families, or just sought a suitor of a similar social level which they could not find close to home (or at least not without risking inbreeding). This is still common practice among the high aristocracy nowadays. This explains why maternal lineages (mtDNA) and autosomal DNA is much more evenly spread out geographically than paternal lineages (Y-DNA).

  4. Y chromosomes sometimes disappear for evolutionary reasons. Mutations in one lineage can have a negative incidence on male fertility, causing men to have more female offspring (who do not pass on Y-DNA), have less children (contraction of the Y-DNA lineage), or in extreme cases even become sterile (extinction of the Y-DNA lineage).

  5. Y chromosomes may suffer dramatic decline in frequency due to wars, in the event men from a tribe or ethnic group are killed in large numbers by their opponents, and their women taken by the winners. Since autosomes are also passed on by women, autosomes would survive such a scenario even if all male lineages went extinct (which was probably very rare, but once in history is enough to affect a region permanently).

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