Reshaping the Hexagone: the genetic landscape of modern France

[Grace O'Malley]

Reshaping the Hexagone: the genetic landscape of modern France

Simone Andrea Biagini, Angel Carracedo, David Comas, Francesc Calafell

doi: https://doi.org/10.1101/718098

Abstract

Unlike other European countries, Metropolitan France is surprisingly understudied. In this work, we combined newly genotyped samples from various zones in France with publicly available data and applied both allele frequency and haplotype-based methods in order to describe the internal structure of this country, taking advantage of the Human Origins SNP array, specifically designed for human population genetics studies. We found out that French Basques are genetically distinct from all other populations in the Hexagone and that the populations from southwest France (namely the Franco-Cantabrian region) are intermediate between Basques and other populations. Moreover, Bretons slightly separated from the rest of the groups and a link with the historical gene flow from the British Isles has been found. Results from the allele frequency analyses point to a general background that appears to be a mixture of two components, one closer to Southern Italy and the other to Ireland. This combination may be the result of a contact happened in two different moments: in the Early Neolithic, and then Ireland would be a proxy for the continental pathway for the Neolithic wave of advance and South Italy for the coastal penetration, or the Iron Age, when the Celtic and the Mediterranean worlds met in France. On the other hand, results from the haplotype-based methods describe a more structured landscape, highlighting the presence of areas characterized by differential links with the neighboring populations, possibly reflecting a more recent history.

https://www.biorxiv.org/content/bior...18098.full.pdf

Will discuss this later.

[Daco Celtic]

Thanks for posting this. I found this interesting:

"With the admixture analysis, a more ancient and homogeneous background was found.
The homogeneity we detected affected all the French departments, with one important
exception: Brittany, whose connection to the Irish samples completely agrees with
previous findings (Dubut et al., 2004; Ramos-Luis et al., 2014; Karakachoff et al., 2015).
Historical migrations from Ireland to Brittany are well recorded since the 4th century CE
(Monnier, 1997), as well as the emigration of Irish people during the War of Ireland
(1641-1651) into the present day departments of Finistère (FI) and Cȏte d’Armor (CdA),
within which a higher integration of the Irish immigrants is proved by records of marriage,
birth and death certificates (Dubut et al., 2004). Additionally, the Irish admixture signal
may be a proxy for the Celtic British (mostly Welsh and Cornish) migration into Brittany
also in the 4th century CE (see below). Furthermore, a Celtic root for the Breton language
links the Breton departments to the Insular Celtic languages from the British Isles (Forster
et al., 2003). "

[Lucas]

Reshaping the Hexagone: the genetic landscape of modern France


Will discuss this later.

There is also other new paper on French genetics discussed. https://www.theapricity.com/forum/sh...40#post6153840

But in this one also there isn't any info if samples were collected in such way that only people with four grandparents from specific department were included. Birth in department means nothing.

[Creoda]

Located in the center of Western Europe, Metropolitan France acts as a bridge connecting
Northern Europe to the Mediterranean and the Iberian spaces. Nowadays, France is a
cosmopolitan country whose society is shaped by a plurality of lifestyles and truly
different ethno-cultural diversity. Without any doubt, the impact immigrations from
colonised countries to mainland France, such as the migration of Arabs and Berbers from
Algeria which was the most extensive of all colonial migrations to Western Europe before
the 1960s (MacMaster, 1997), enriched the modern genetic landscape of the French
territory.

Enriched

[Leto]

Enriched

After 50+ years in France they're as French as it gets

[Lucas]

There is also other new paper on French genetics discussed. https://www.theapricity.com/forum/sh...40#post6153840

But in this one also there isn't any info if samples were collected in such way that only people with four grandparents from specific department were included. Birth in department means nothing.

For example in this paper they stated that all samples has four grandparents from 50 km radius.
https://www.nature.com/articles/s41431-019-0361-1