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Friday, August 14, 2015

Testing for genetic continuity in Poland from the Bronze Age to the present

The recent Allentoft et al. paper on the ancient genomics of Eurasia featured an Early Bronze Age Corded Ware/proto-Unetice individual belonging to Y-haplogroup R1a. His remains came from a kurgan burial in present-day Greater Poland, or Wielkopolska, known as one of the four Pyramids of Wielkopolska.

Of course, R1a is by far the most common Y-haplogroup in Poland today, and Greater Poland is generally accepted to be the cradle of the Polish nation.

It's tempting to think that all of this isn't just a happy coincidence, and that this kurgan man and/or his close relatives are the ancestors of modern-day Poles. Considering that we have some of his genome, can we actually test this hypothesis?

Unfortunately, the sequence by itself is too limited to allow such a high resolution analysis. However, the Allentoft et al. dataset includes six other Bronze Age samples from Poland; one other Corded Ware individual from Greater Poland, and five Unetice individuals from Silesia. Thus, it's possible to combine these samples and at least run a preliminary analysis comparing them to present-day Europeans, including Poles, to test their affinities.

The only reliable way to do this is to use formal statistics, and specifically D-statistics. That's because, unlike model-based analyses, D-stats ignore recent genetic drift and, unlike f3-stats, they're able to discriminate correctly at a very fine scale between samples with somewhat different numbers of markers. Below are two sets of results of the form D(Outgroup, PopulationTest) (Population1, Population2).

D(Ju_hoan_North, Poland_Bronze_Age) (BedouinB, European)

D(Ju_hoan_North, Poland_Bronze_Age) (Polish, European)

Basically, what the results show is that western Poland was inhabited by a very northern people during the Bronze Age. They were similar to present-day Balts, Scandinavians, Irish, and Poles.

Indeed, in these sorts of tests small Northern European countries tend to get the best scores with most prehistoric Europeans. I believe that this isn't just because of shared ancestry, but also relative isolation and homogeneity. So the fact that Poland is the only really big country at the top of the list above might be very important.

That's pretty much it for now. As far as I can see, there's nothing to suggest that present-day Poles can't be the direct descendants of these ancients. But as I say, this was a preliminary analysis and a work in progress. I'll revisit this issue when more samples come in. By the way, I also ran a bunch of other D-stats that might be of interest.

D(Ju_hoan_North, Bell_Beaker) (BedouinB, European)

D(Ju_hoan_North, Corded_Ware) (BedouinB, European)

D(Ju_hoan_North, EHG) (BedouinB, European)

D(Ju_hoan_North, Hungary_BA) (BedouinB, European)

D(Ju_hoan_North, Loschbour) (BedouinB, European)

D(Ju_hoan_North, Motala_HG) (BedouinB, European)

D(Ju_hoan_North, Stuttgart) (BedouinB, European)

D(Ju_hoan_North, Unetice_EBA) (BedouinB, European)

D(Ju_hoan_North, Yamnaya) (BedouinB, European)

It's useful to plot D-stats against each other when looking for patterns in the data. For instance, in the graphs below Basques and southern French often look like obvious outliers. What this means is that there's something peculiar about their genetic history. What might that be I wonder? Any suggestions?

The present-day Polish samples, eleven in all, came from here. Most of the other samples are from the Allentoft et al. (Rise Project), Haak et al. and Lazaridis et al. datasets, all of which are publicly available.

See also...

R1a-Z280 from Early Bronze Age Northern Poland

R1a1a from an Early Bronze Age warrior grave in Poland


CroMagnon said...

I doubt that there's direct descent from corded ware groups.
There has been way too much flux between CWC and Piast Poland for that. Rather, modern Poles descend, for the most part, from several groups, some of which are indeed ancestral to CWC, but perhaps not those very same ones from bronze age Wielkopolska.

Krefter said...

What about the Slavic migrations? Did the Slavs come from east of Poland?

Davidski said...

I doubt it.

M458 is the Slavic marker and it peaks in Western Slavs, including Czechs and Slovaks, who don't have much in common with East Slavs, at least relative to their western neighbors like Germans and Austrians.

Dmytro said...

Where, in your opinion, do the other Slavic markers, viz., M558 and CTS10228 stand?

Davidski said...

M558 might be in large part a Baltic marker. The early Slavs expanded over a huge stretch of Baltic-speaking territory, so a lot of Slavs today, especially East Slavs, carry Baltic lineages.

CTS10228 probably derives from southern Poland, but its launching pad with the Slavic expansions to the Balkans was probably further east.

CroMagnon said...

M458 is not "the" slavic marker. It's *a* marker which expanded (or subgroups within) c. 500 AD. Afaik, most R1a in the Balkans is from Z280

Davidski said...

Well I doubt the Proto-Slavs rushed for the Balkans as soon as they appeared.

Don't conflate the birth of a people with their first major expansions.

batman said...

"Slavic" is a language, developing during late Roman times, as a 'lingua franca' of the trading communities around the Black Sea.

Thus there were never a "slavonic dna" - but rather a linguistic communion that developed the *slavonic-speaking' peoples. Mist of them were formerly prt of the Bulgars, who used to share language with the Hungarians and the Venedae, aka Sarmatian/Scytian.

The spread of the slavonic language goes hand in hand with the spread of the Eastern Roman Empire to the north. Thus it was Method and Cyril who got the task to form a cyrilian writing-system, to cover the language that had developed around the northern areas of the Black Sea.

Since Justitian it kept conquering new grounds up north - especially along the trade-routes/waterways towards the Balkans and the Baltic Ocean, where the North European markets were.

Since the russians (also) submitted to the trade-union of Konstantiopel - and thus converted to the Greek church - the slavonic languages could spread all along the northern areas too, from the vendic Vistula (slavonic: Wizla) to the uralian Venedae/Vänejä/Russians.

The spread of the Slavonic languages - as well as the Greek church - are clearly a case of cultural diffusion, NOT demic.

Davidski said...

That's ridiculous.

batman said...


Is there any line of reason, bassed on facts rather than assumptions - to explain such a blunt conclusion?

batman said...

"If some prospective descendants of the Eulau haplotype carries lived until today, theirs actual haplotype must have a difference of GD=2 - 4, for the regularities discovered until this time say that each haplotype begins to mutate in a certain number of generation. It means that people today being with such difference from the Eulau haplotype can deem themselves as prospective descendants or close relatives of the people burried in Eulau 4 600 years ago."

"Haplotypes close to the Eulau haplotype up to a genetic distance 4 originate only from Norway, Great Britain, Czech Republic, Slovakia and Slovenia. Not untill the GD=5 the other European countries do occur."

"This discovery represents another argument against the statement that each R1a haplogroup carrier living today in our country is of so-called Slavic origin. It is already the second support of the fact that R1a haplogroup has occured in middle Europe since the Neolith. It is likely that the people with haplotypes close to those from Eulau were the first, or the ones of them, who brought the R1a haplogroup to middle Europe."

"The fact that the recent haplotypes closest to the one from Eulau can be found in Norway, Great Britain, Czech Republic and Slovakia can point to a probable origin of R1a amongst Celts and Germans."

So the question remians - what haplotype is supposed to signify a "slavic" patriliniality ('tribe').

Davidski said...

Low resolution STR haplotypes won't tell you much about R1a lineages, because 99% of the R1a in the world comes from a massive and rapid expansion and founder effect from Eneolithic Eastern Europe. The people expanding were early Indo-Europeans and ancestors of the Corded Ware.

That's why using a few STR markers a Norwegian R1a can look a lot closer to an Indian R1a than to another Norwegian R1a.

Slavic R1a lineages are just a subset of this massive Corded Ware R1a expansion.

Krefter said...

Why would all ancient northern genomes be closest to the same set of people in the same order? It makes sense for Corded Ware and Bell beaker because they had a lot of ANE, but definitely not for Bronze age Hungary. Unless you're using the Hungarian who had a lot of WHG. Is this just a limitation of D-stats?

stan the man said...

eurogenes eutest v2 k15 admixture proportions.
I do know all grandparents were Lithuanians out of Russia, early 20th century. analysis stated I am 96%eastern European, 4% finnish, western Russian..big deal..I am a white man. your report has a breakdown by this what my dna actually is.
thanx for any help if you have a chance to answer me
based upun the historic enmity between the Poles and Lithuanians , I was surprised (not really) form one of the other GEDMATCH reports if I interpreted it correctly that I am 16% Polish

Davidski said...

Your results seem to make sense Stan.

There was that Polish-Lithuanian Commonwealth and stuff, so nothing really surprising.

Apart from that, maybe read this and my other blogs when you get some time. Might be useful as you try and work out the finer details about your ancestry.