Genes and Geography (Italy vs. Britain)

January 16, 2020

All else being equal, genes mirror geography in Europe. We've already seen this by comparing Italians to Germans, and now we can do another similar comparison. A new study that has even better geographical coverage than Sazzini et al. (2016) shows the samples clustering to form an almost perfect map of Italy, while another new study shows the same thing in the British Isles.

[NOTE: For the samples in gray, "NWEur" is actually Southern French, "WEur" are Spanish and Portuguese, and "SEEur" is Greeks.]


Raveane et al. "Population structure of modern-day Italians reveals patterns of ancient and archaic ancestries in Southern Europe". Sci Adv, 2019.


Gilbert et al. "The genetic landscape of Scotland and the Isles". PNAS, 2019.

2 comments

gamerz_J said...

Neat blog, stumbled upon it looking for more information on Italian and Roman genetics.

If you have some time, I was wondering if you know what this Iranian-like component is in Italians and whether Iran_N or CHG is a better fit?

Furthermore, do you know if there is any substantial Levant_N or Natufian admixture in Italians? I am not sure there is but some have argued as much.

Sarah Nikas said...

Gamerz_J:

The component is specifically from the Caucuses and not Iranian. This was true for all of europe, including italy, which was studied here: https://mega.nz/#!svgRAALa!sjcnF0bPFbOKbHHxPTXCIVkjSrr8hMn4LXE6oUupOXc

The Neolithic Iranians and Caucuses Hunter gatherer components are similar and even difficult to distinguish, however only the caucuses component is representative in europe and N Iranian is found scarcely these days even in Iran.

As far as I can tell there is no basis for proporting levantine/natufian admixture in italians. The only part of italy that has had any notable colonies from south of the mediterranean was sicily and in all cases those colonies were exterminated and their inhabitants deported - usually through slavery.