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Tuesday, February 28, 2012

Oetzi the Iceman: more Middle Eastern than the average modern Euro


So, Oetzi the Iceman from the Copper Age Tyrolean Alps has turned out more Middle Eastern than the majority of present-day Europeans. You can see that result on the first PCA below (a), where Oetzi (black dot) is closer to the Middle Eastern samples than even most modern Italians (orange dots). Unfortunately, the article doesn't resolve why this is so. But one possibility is that almost all Europeans today, except those from the Mediterranean coastline, have more North European or North European-like ancestry than Oetzi, pushing them up and right on that PCA, away from the Middle East. In any case, this result makes it tough to argue that the ancestors of most modern Europeans (the Y-chromosome R1a and R1b crowd) arrived on the continent after Oetzi's kind (the Neolithic Y-chromosome G crowd). It appears as if they were already there, at the same time as the Iceman, and probably earlier, and then expanded down into South Europe later, leaving only more isolated areas, like Sardinia and Corsica, relatively untouched.


The image above of the figures + tables was edited by me to make it a little more informative than the original. Below is the abstract from the study, and here is the Iceman genome browser. Can anyone tell me where & how I can download this guy's SNPs, so I can make him a Eurogenes project member?

The Tyrolean Iceman, a 5,300-year-old Copper age individual, was discovered in 1991 on the Tisenjoch Pass in the Italian part of the Ötztal Alps. Here we report the complete genome sequence of the Iceman and show 100% concordance between the previously reported mitochondrial genome sequence and the consensus sequence generated from our genomic data. We present indications for recent common ancestry between the Iceman and present-day inhabitants of the Tyrrhenian Sea, that the Iceman probably had brown eyes, belonged to blood group O and was lactose intolerant. His genetic predisposition shows an increased risk for coronary heart disease and may have contributed to the development of previously reported vascular calcifications. Sequences corresponding to ~60% of the genome of Borrelia burgdorferi are indicative of the earliest human case of infection with the pathogen for Lyme borreliosis.

Keller et al., New insights into the Tyrolean Iceman's origin and phenotype as inferred by whole-genome sequencing, Nature Communications, Volume: 3, Article number: 698, DOI: doi:10.1038/ncomms1701


5 comments:

princenuadha said...

" It appears as if they were already there, at the same time as the Iceman, and probably earlier, and then expanded down into South Europe later,leaving only more isolated areas, like Corsica and Sardinia, relatively untouched."

So which places even had more Meso European around the time of otzi? The only places I know of that had a lot of meso around otzi's time were northern Europe (don't know about the British isles), the Baltic area, and eastern Europe.

Then they would have to spread the R's along with meso, which I couple, within a short time frame.

I like to think it was eastern Europe that spread the r's and meso... But I guess you basically think it was the Baltic area (a thoery I hadn't heard before).

Fanty said...

"But I guess you basically think it was the Baltic area (a thoery I hadn't heard before)."

Dont forget, people didnt live at the places where they live today.

- "Traditional" ideas about the origins of the Balts see them migrating from north of the Black sea in relative recent times.

- some time back, there was a study about the blue eyes mutation. In wich Danish scientists claimed, the blue eyes mutation would have originated 8K YBP northwest of the Black Sea.
The modern population wich has the highest levels of that mutation are modern day Lithuanians.

- A study about hunter-gatherer mtDNA in CENTRAL Europe (Germany, Poland, Czechia, Hungary etc) suggested that these people now live in the Baltic states.

In other words, genetical connections to the modern day Balts would not suggest origins in what is now geographically the Baltic states, as these Balts themselfs dont originate from that place.

jeffhsu3 said...

Did you ever find out how to download Oetzi's genome?

Davidski said...

Yes, it's available online, but I don't have the link on me. I got it sent to me as a plink file by someone anyway.

Shin.and.Ginger said...

Oetzi's genome is presented in a value-added interactive browser at http://icemangenome.net/.

That may sound like more spectacle than science, but I found the site to be usefully annotated and rich with contextual visualisation.