North European Component Variation within the Eurasian Heartland [Original Work]

As DNA variation across Asia have progressed over the years (Wells et al., Xing et al., teaser mtDNA results from Burger et al.'s upcoming analysis of prehistoric Eurasian steppe remains), the prevailing theme of ancestral markers with origins in Europe has remained a frequent one, particularly with regard to the expansion of Bronze Age semi-pastoral nomads from the Pontic-Caspian steppe bearing the Indo-European languages.

David W. of the Eurogenes Genetic Ancestry Project has recently posted data online from a new Intra-European run using ADMIXTURE (K=12) with the intention of breaking up the North European component that often arises through the program. Spreadsheet results here.

This brief investigation seeks to identify the North European-derived component patterns within Asia by first mapping out the frequencies and then correlating with Eurogenes' release notes on each.

Method
As many samples from immediately-identifiable populations were obtained from the spreadsheet results (link above). No sample restrictions were implemented. Averages of each population were calculated, except where n=1. No modifications made to population labels except for Eurogenes population averages, denoted by the addition of a _Eg suffix. Populations were then allocated into arbitrary regional groups, allowing results to be displayed more coherently.

Results
Tabulated results can be found in the Data Sink. Autosomal variation per Regional Group can be found below:











The North European-derived components, despite their exceptionally close Fst. distances relative to the other components, do seem to reveal a few interesting trends;

• Northeast European appears to (at least partially) be the result of allele sharing with populations further east, as evidenced by its' predominance in East-Central Asian groups, as well as extending even further eastwards into the Siberian Selkup (n=1). This component has a circumstantial correlation with the craniometric and ancient mtDNA evidence suggestive of a "migration corridor" between Eastern Europe and Siberia (Malyarchuk et al.'s On the Origin of Mongoloid Component in the Mitochondrial Gene Pool of Slavs, Newton's Ancient Mitochondrial DNA From Pre-historic Southeastern Europe: The Presence of East Eurasian Haplogroups Provides Evidence of Interactions with South Siberians Across the Central Asian Steppe Belt). While it also explains this component's abundance in North Caucasian populations (lie en route between Ukraine and Siberia), the same cannot be said with absolute certainty of South-Central Asia. With that being said, the 0.021 Fst distance with West European despite the markedly different distributions suggests both are the result of prehistoric (possibly paleolithic?) hunter-gatherer migration paths across large swathes of Eurasia.
• West European has a sporadic appearance across with an Asian peak in the North Caucasus. This implies - Staying true to its' assigned label - It is a generic West Eurasian component that has reached a maximum in Western Europe, with the North Caucasus representing the closest point of reference to there. Indeed, this inference is made independently by Eurogenes, albeit using different parameters;

"I used samples of Scottish, Irish and Western English ancestry to create this cluster. Not surprisingly, it peaks in individuals of Western Irish descent. However, it also peaks in Basques and many Iberians, which is fascinating, because that makes it the autosomal equivalent of Y-chromosome haplgroup R1b in Europe."

• North Sea and South Baltic accompany one another at similar frequencies across much of Asia, especially in populations with an Indo-Iranian-speaking heritage (observe the ~0.8-1:1 ratio among Kurds, Iranians, the Turkmen, Uzbeks, Tajiks, Brahmins, Kshatriya's and Kyrgyz as examples of this). It is interesting to note that, of the two, only the North Sea component is readily present in East-Central Asians. The only other likely migration path along this trajectory is that of the proto-Tocharians, who (under the Eurasian steppe theory) split off from the Proto-Indo-European homeland several millennia prior to the Proto-Indo-Iranians that eventually formed the Andronovo archaeological horizon from Sintashta/Pit Grave (E Kuz'mina, The Origin of the Indo-Iranians, pg.451). Perhaps this near-solitary North Sea component within the Altaians, Mongolians and Uyghurs is attributed to early speakers of Tocharian? Perhaps the elevated presence of the North Sea component in South-Central Asia (Jatts, Pathans, Kyrgyz) is a relic of the Kushans, nomads supposedly a part of the Yuezhi confederacy, who may have been Tocharian speakers themselves? 
• One curious phenomenon is the similar West European-North Sea-Northeast European component proportions across the Turkmen, Uzbeks, Kyrgyz, Pathans, Uttar Pradesh Brahmins, Altaians and the Uyghur. Whether this can be substantiated in any way, or whether it is simply an anomalous association predicated by non-uniform and varying sample sizes, prevents a firm conclusion from being made.
• North European-derived frequencies among Southwest Asian Semitic-speaking groups shown here seldom exceed 1% apiece and are either the result of recent, inconsistent small-scale admixture events or are simply background noise generated by ADMIXTURE.

Summary

The Northeast European and West European components appear to have a distribution independent of any significant migration events since the Neolithic, instead being associated with either the "migration corridor" across Eurasia or simply being the result of mutual West Eurasian heritage. North Sea and South Baltic, on the other hand, do seem to correlate with one another and support (rather than contradict) the eastward movement of Bronze age semi-pastoral nomads speaking early dialects of Proto-Indo-European.

Edit I [31/03/2012]: Correction of erroneous Brahmin results due to Google Spreadsheet lag.