Western vs eastern Iberia -- is there a genetic gradient?

[Sikeliot]

It has been proposed on here that no, Iberia does not face a north to south gradient like Italy does, but an east to west one, meaning that Catalans, Valencians, Aragonese, etc. differ genetically from Portuguese, Galicians, Extremadurans, etc.

Is this backed up genetically?

[quediustu]

The main genetic cline in Iberia is north-south, as it is in everywhere in Europe.
I can't thing of anything that would make the east different than the west. If anything the west got a bit more of external influences.

[Sikeliot]

The main genetic cline in Iberia is north-south, as it is in everywhere in Europe.
I can't thing of anything that would make the east different than the west. If anything the west got a bit more of external influences.

People on here have said that Iberia has no north to south gradient, because southern Spain was repopulated from the north following the Reconquista.

All of the evidence I have seen shows elevated North African and SW Asian, by a slight amount, in western Iberia.

[Gaston]

Yes, both lineages and autosomal DNA gives Western Iberia more diversity.

[Sikeliot]

I will have to look at some results more carefully to see.. because if the "non-European" elements rise slightly in western Iberia, I am curious to see what other components rise or fall along with it.

[Empecinado]

People on here have said that Iberia has no north to south gradient, because southern Spain was repopulated from the north following the Reconquista.

All of the evidence I have seen shows elevated North African and SW Asian, by a slight amount, in western Iberia.

And northern Spain was repopulated from south to north too. Many Christians from the south, the Mozarabs, moved to the north fleeing from Muslim opression.

[gold_fenix]

i doubt it, quediustu , if even could East-West , thing i doubt it too

http://i37.photobucket.com/albums/e87/Divad_Ocsarrac/me_zps51813d09.png
this is me in the map, i am the green point

the person on the left of myself is half basque/half Burgos and in the right totally from the North of Aragon

[Sikeliot]

An east to west gradient makes sense, since Spain is connected to the rest of Europe on its northeastern side, and is close to North Africa on its southwestern side.. therefore when people moved into Spain from either direction, they would have to move either northeast or southwest.

Thus, the real gradient should be northeast to southwest.

[Ibericus]

There is a lot of overlap between regions on PCA plots. The patterns I see is the amount of "basqueness", and the closeness to French, which seems lower in regions like Extremadura , Murcia, Portugal, and highest in Aragon/Cantabria/Catalunya/Valencia, other than that, the rest of regions seem a bit random :

http://oi59.tinypic.com/soyeew.jpg

[quediustu]

People on here have said that Iberia has no north to south gradient, because southern Spain was repopulated from the north following the Reconquista.

All of the evidence I have seen shows elevated North African and SW Asian, by a slight amount, in western Iberia.

According to wikipedia only 4% of the total population at that time was expulsed. Even if this loss had been repopulated completely, it is very few. Plus the main population loss was in Valencia, which isn't southern proper.

Also I remember reading somewhere that while the majority of moriscos left, some didn't and relocated to northwestern Castile because apparently they were less discriminated there. This may explain for the more elevated NA in those places.

[Sikeliot]

Some people though say that there is higher affinity to what they call "Atlantic Europe" in western Iberia, which would mean that the true reduction is in ancestry that is shared with places like Italy and Greece. I spend so much time analyzing Italy and Greece that I've neglected to do the same for Portugal and Spain.

[Cristiano viejo]

An east to west gradient makes sense, since Spain is connected to the rest of Europe on its northeastern side, and is close to North Africa on its southwestern side.. therefore when people moved into Spain from either direction, they would have to move either northeast or southwest.

Thus, the real gradient should be northeast to southwest.
The day that you go to that part of Spain you will get a surprise.

[gold_fenix]

Well the people i share in 23andme who are Spaniards of different zone , there isn't to exist a correlation by zones of origin, they can cluster in any point inside of iberian cluster

[Sikeliot]

Well the people i share in 23andme who are Spaniards of different zone , there isn't to exist a correlation by zones of origin, they can cluster in any point inside of iberian cluster

I notice that Galicians and Portuguese do end up further from the "Basque" cluster than many Spaniards, as I share with someone of Valencian origin who is closer to the Basque cluster than any of the Portuguese I share with.

[quediustu]

i doubt it, quediustu , if even could East-West , thing i doubt it too

http://i37.photobucket.com/albums/e87/Divad_Ocsarrac/me_zps51813d09.png
this is me in the map, i am the green point

the person on the left of myself is half basque/half Burgos and in the right totally from the North of Aragon

The map is too big and encompasses too many populations to make it representative for iberians.

[Lábaru]

The difference is minimal north and south, and east and west, we are an isolate peninsula with homogeneous people.
http://3.bp.blogspot.com/-ABTZXvdsvmw/Tq169iE-UzI/AAAAAAAAACc/eMYNAcjqDPQ/s1600/pueblos-prerromanos.jpg
http://ocw.unican.es/humanidades/historia-antigua-de-la-peninsula-iberica/seminarios/mapa-de-los-pueblos-prerromanos/image

[Lábaru]

The map is too big and encompasses too many populations to make it representative for iberians.

The main genetic cline in Iberia is north-south, as it is in everywhere in Europe.
I can't thing of anything that would make the east different than the west. If anything the west got a bit more of external influences.

Inn this map we can see that northern Spanish and Andalusians we are together in a point, with galicians and Valencian too.
http://abload.de/img/mds_mfa_eutest0gzcn.png

[Mn The Loki TA Son]

The day that you go to that part of Spain you will get a surprise.

:thumb001:

[Damião de Góis]

This picture posted by Ibericus on another thread sums it up quite nicely (it's the Eurogenes K15 run):

http://oi57.tinypic.com/2ldkhp2.jpg

[Mn The Loki TA Son]

Since you have been analyzing Italy and Greece, do you think she could pass in Italy or Greece? Iberian descent that moved and live in N Mexico :cool:
http://i821.photobucket.com/albums/zz138/yoyochickenkfc/20140615_204343_zpsf9ef3740.jpg

[quediustu]

Inn this map we can see that northern Spanish and Andalusians we are together in a point, with galicians and Valencian too.
http://abload.de/img/mds_mfa_eutest0gzcn.png

Still we can see the gradient north-south clearly. Notice that the distance between "german" and "west scottish" is the same even though it concentrates many different populations.
And we cluster together because we're the only territory that has been divided in many parts. If you did the same with all regions in France you'd see a continuum, and the same goes for all of Europe. I'm sure that both sides of the Pyrenees would be closer to each other than to Andalusia, after all Iberia is very big (for european standards) and distance is very important when analyzing a genetic gradient.
This map shows it:
51892

[Lábaru]

Still we can see the gradient north-south clearly. Notice that the distance between "german" and "west scottish" is the same even though it concentrates many different populations.
And we cluster together because we're the only territory that has been divided in many parts. If you did the same with all regions in France you'd see a continuum, and the same goes for all of Europe. I'm sure that both sides of the Pyrenees would be closer to each other than to Andalusia, after all Iberia is very big (for european standards) and distance is very important when analyzing a genetic gradient.



The difference is ridiculous, Italy and other countries have differences but in the Iberian peninsula are very small, we are the same people.

Eurogenes K15
http://oi57.tinypic.com/2ldkhp2.jpg

if you are looking for any reason to divide Spain, genetics and science are not going to help you.

[quediustu]

The difference is ridiculous, Italy and other countries have differences but in the Iberian peninsula are very small, we are the same people.
http://oi57.tinypic.com/2ldkhp2.jpg

If you calculate the north sea + atlantic + baltic + east euro for each iberian region you can see the gradient. Northern Iberia having more and southern Iberia less, and the contrary with southern elements like meds, red sea, etc.

Look at the southwest_French, even being in France it is closer to the populations at the other side of the Pyrenees than to the general french result. As I said before, it is a continuum. Pretty sure that someone from Catalonia or northern Aragón would be closer to someone from Toulouse than the former are to Portugal or Andalusia.

We're homogenous if compared to a distant population like the polish for example, but not when it is an immediate region like southern France.


And btw lol at the low atlantic result for Galicia and Portugal :biggrin::biggrin: The rest of Iberia is on par with the british isles though.

EDIT: And Italy is special due to the greek colonization.

[quediustu]

if you are looking for any reason to divide Spain, genetics and science are not going to help you.

We're talking about Iberia and not Spain, don't discriminate the portuguese in this please.

I think it is obvious but I'll say it anyway: genetics don't understand about political boundaries.

[Damião de Góis]

And btw lol at the low atlantic result for Galicia and Portugal :biggrin::biggrin: The rest of Iberia is on par with the british isles though.


"Atlantic" is more of a basque component as it can be seen, so the result which you consider funny makes perfect sense.


As for the rest, you have a good way of proving your theory: do 23andme and post your results here. Then we'll see if you cluster with the french or with iberians.

[Lábaru]

If you calculate the north sea + atlantic + baltic + east euro for each iberian region you can see the gradient. Northern Iberia having more and southern Iberia less, and the contrary with southern elements like meds, red sea, etc.

Look at the southwest_French, even being in France it is closer to the populations at the other side of the Pyrenees than to the general french result. As I said before, it is a continuum. Pretty sure that someone from Catalonia or northern Aragón would be closer to someone from Toulouse than the former are to Portugal or Andalusia.

We're homogenous if compared to a distant population like the polish for example, but not when it is an immediate region like southern France.


And btw lol at the low atlantic result for Galicia and Portugal :biggrin::biggrin: The rest of Iberia is on par with the british isles though.

EDIT: And Italy is special due to the greek colonization.


Still the difference is minimal, we're talking about ridiculous amount, and too exist east Vs west, but again a ridicolous amount. Even South French are very similar to Andalusians, the numbers are clear.

[Empecinado]

According to wikipedia only 4% of the total population at that time was expulsed. Even if this loss had been repopulated completely, it is very few. Plus the main population loss was in Valencia, which isn't southern proper.

Also I remember reading somewhere that while the majority of moriscos left, some didn't and relocated to northwestern Castile because apparently they were less discriminated there. This may explain for the more elevated NA in those places.

The NA is more elevated in those places for other reasons. There was a migration from North Africa in the late Paleolithic, but after the Indo-European and Neolithic farmers invasions was replaced in most of Spain, except in isolated regions less attractive to farm life led by these newcomers and more away from the Pyrenees, which was their entry point, and these are the conditions that meet the highest NA regions: Extremadura, valley of Pas, the mountainous areas of Leon and Galicia, all share being remote areas and/or bad for agriculture.

[Lábaru]

Another map, we can see that there is a clear Iberian point group, while other nationalities, French and Italian etc ... are scattered, split with bigger distances, this is an indisputable fact.
http://imageshack.com/a/img834/7859/c0zu.png

[quediustu]

"Atlantic" is more of a basque component as it can be seen, so the result which you consider funny makes perfect sense.


As for the rest, you have a good way of proving your theory: do 23andme and post your results here. Then we'll see if you cluster with the french or with iberians.

A basque component that's higher in the british isles than in Galicia and Portugal aka western Iberia? I'm not a genius but I'm sure the dude who did those runs knows what he is doing, so I'll trust his decision to call it "atlantic".

And no need to get defensive, I'd like to do the 23andme thing so if you want to see my results you can contribute with €€€ to make it happen. As for a guess, I think I'd score closer to the people of Languedoc-Roussillon than to the portuguese. Mainly because catalans are native to that region and also because the distance between were I'm from and there is shorter and to Portugal. Now if it's the aragonese then we're closer bros with them (iberian powa!). As I said before Iberia is big and distance matters a lot.

[quediustu]

Still the difference is minimal, we're talking about ridiculous amount, and too exist east Vs west, but again a ridicolous amount. Even South French are very similar to Andalusians, the numbers are clear.

Then again, we look homogeneous from a global european perspective, but if you analyze a smaller region like Iberian and southern France, you can begin to see the difference and how a gradient forms.



Another map, we can see that there is a clear Iberian point group, while other nationalities, French and Italian etc ... are scattered, split with bigger distances, this is an indisputable fact.
http://imageshack.com/a/img834/7859/c0zu.png

The french there got very few samples, so we can almost guarantee that they didn't test people from every region in France. If they did I'm sure you'd see a continuum like the one with brits - germans - scandinavians - baltics - slavs that the map shows.

I think I made my points very clear and even using the material you and others provided. The genetic continuum is obvious and for example a german and a dutchman who live near the frontier will cluster closer together than that same german with someone from Stuttgart. As I said Iberia is big and this is shown too by the fact that the circle grouping all iberians is as big as the one grouping the english, scottish, germans, danish, dutch, irish. In other words, all these populations have the same genetic diversity as Iberia. In general, geographical distance correlates very well with genetic distance.

I've already set my arguments and I won't go further with this discussion because then I'd be repeating myself.

[Lábaru]

Then again, we look homogeneous from a global european perspective, but if you analyze a smaller region like Iberian and southern France, you can begin to see the difference and how a gradient forms.

You can see Cantabrians, Catalans, Valencians, Castilians etc ... very close together, and French, even South French, a bit more far. Only one Catalan among many is close to French, the rest of Catalan are closer to Extremadura and Andalusia than a France
http://imagizer.imageshack.us/a/img834/7859/c0zu.png

[Damião de Góis]

A basque component that's higher in the british isles than in Galicia and Portugal aka western Iberia? I'm not a genius but I'm sure the dude who did those runs knows what he is doing, so I'll trust his decision to call it "atlantic".

I think it's quite clear that it peaks in French Basques. Don't know how that can be the subject of discussion, all you have to do is look at the picture again.


And no need to get defensive, I'd like to do the 23andme thing so if you want to see my results you can contribute with €€€ to make it happen. As for a guess, I think I'd score closer to the people of Languedoc-Roussillon than to the portuguese. Mainly because catalans are native to that region and also because the distance between were I'm from and there is shorter and to Portugal. Now if it's the aragonese then we're closer bros with them (iberian powa!). As I said before Iberia is big and distance matters a lot.

I'm not being defensive, just telling you that you would fall in the iberian cluster. I've never seen any iberian falling outside of it except for basques.
I can see that this is a disappointment for you. So maybe i wouldn't recomend that you do this test.

[quediustu]

You can see Cantabrians, Catalans, Valencians, Castilians etc ... very close together, and French, even South French, a bit more far. Only one Catalan among many is close to French, the rest of Catalan are closer to Extremadura and Andalusia than a France

I have edited the last post to include the answer to the map.



I'm not being defensive, just telling you that you would fall in the iberian cluster. I've never seen any iberian falling outside of it except for basques.
I can see that this is a disappointment for you. So maybe i wouldn't recomend that you do this test.

Don't worry for me because I don't need to fake being someone that I'm not.

[quediustu]

The NA is more elevated in those places for other reasons. There was a migration from North Africa in the late Paleolithic, but after the Indo-European and Neolithic farmers invasions was replaced in most of Spain, except in isolated regions less attractive to farm life led by these newcomers and more away from the Pyrenees, which was their entry point, and these are the conditions that meet the highest NA regions: Extremadura, valley of Pas, the mountainous areas of Leon and Galicia, all share being remote areas and/or bad for agriculture.

Is that your theory or did you read it somewhere else? It seems very unlikely to be honest. Paleolithic iberians found at the moment show no signs of NA admixture. Also I think we can agree that the basques are the most isolated in Iberia, and in fact they're the only ones not showing NA.

[Gaston]

Is that your theory or did you read it somewhere else? It seems very unlikely to be honest. Paleolithic iberians found at the moment show no signs of NA admixture. Also I think we can agree that the basques are the most isolated in Iberia, and in fact they're the only ones not showing NA.

It's still all speculation but the hypothesis is not unrealistic. Besides, Iberia is very big so I doubt the population was monolithic and only populated by La Braña type people (who are very Northeast European-like) before the neolithic. Just look at the recent paper on Hungary: neolithic people from the same region being genetically very different from each other.

There is also a possible Bell Beaker link with North Africa, which would put all Western Europe as NA influenced.

Basque people are actually NA influenced too, much less than Iberia of course, and more in line with the French. There is even one mtdna M1 found in eighth century basques.

[quediustu]

It's still all speculation but the hypothesis is not unrealistic. Besides, Iberia is very big so I doubt the population was monolithic and only populated by La Braña type people (who are very Northeast European-like) before the neolithic. Just look at the recent paper on Hungary: neolithic people from the same region being genetically very different from each other.

There is also a possible Bell Beaker link with North Africa, which would put all Western Europe as NA influenced.

Basque people are actually NA influenced too, much less than Iberia of course, and more in line with the French. There is even one mtdna M1 found in eighth century basques.

We can speculate all we want and create many theories, la braña at least provides some realistic information.
And I have read the papers on Hungary and all was expected and made sense from what we knew even before this study.
North Africa has also changed a lot since the paleolithic. Keep in mind that the sharing is with the actual population of NA, not an ancient one.

And btw I just read that the reason of slightly elevated NA in western Iberia is because they formed a very small community there compared to the east, so instead of expulsing them they were mixed within the general population. I don't know if this is the right answer or not, but it convinces me much more than the paleolithic thing.

[DanielJ1eH]

Where would I fall in this cluster? I'm assuming with Tuscans.

[Sikeliot]

There is also a possible Bell Beaker link with North Africa


This might explain some things about why North African genetic influence is absent in the Balkans but present in the rest of Southern Europe.

[Empecinado]

Is that your theory or did you read it somewhere else? It seems very unlikely to be honest. Paleolithic iberians found at the moment show no signs of NA admixture. Also I think we can agree that the basques are the most isolated in Iberia, and in fact they're the only ones not showing NA.

This is the theory of a chemical friend who has participied in some of these studies. There is too few samples from Upper Paleolithic to draw a conclusion, but this theory is more plausible than the one about Moriscos. There was no Moriscos in the Valley of Pas neither in Galicia, and in Leon and Zamora their number was low and most of them were expelled. Valencia had much more Moriscos, the most important population in Spain and even nowadays is not difficult to see people with Morisco surnames, yet we have very low NA.

The pattern of NA distribution is always the same: isolated areas away from Pyrinees and poor for agriculture. Ie Leon and Galicia mountains and Pas valley, the areas with highest NA. Instead Moriscos were for the most part peasants and lived in areas favorable for agriculture.

[Ibericus]

Where would I fall in this cluster? I'm assuming with Tuscans.
more likely with North Italians

[Damião de Góis]

Don't worry for me because I don't need to fake being someone that I'm not.

Really? I must have got you wrong then.