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  #11  
Old 3rd January 2018, 09:22 PM
Germanica Germanica is offline
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Originally Posted by Dimanto View Post
AncestryDNA always had issues effectively splitting up Italians from Iberians, especially for people of northern Italian ancestry.
I don't think it's just AncestryDNA - I think it's common because neighboring regions tend to share so much DNA, it makes it difficult/impossible to always tell them apart.

Personally, I had one South Italian grandparent, and I get nothing in Iberia from AncestryDNA, FTDNA, 23andMe, or MyHeritage. But that doesn't mean lots of other people don't.
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  #12  
Old 4th January 2018, 06:41 PM
Dimanto Dimanto is offline
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Originally Posted by Germanica View Post
I don't think it's just AncestryDNA - I think it's common because neighboring regions tend to share so much DNA, it makes it difficult/impossible to always tell them apart.

Personally, I had one South Italian grandparent, and I get nothing in Iberia from AncestryDNA, FTDNA, 23andMe, or MyHeritage. But that doesn't mean lots of other people don't.
No, this is nonsense for one: Iberia (lacks the Near Eastern element Italians have) is not really a ''neighboring region'' and secondly the fact that on a PCA Southern Italians are basically inbetween Northern Italians/Iberians and some populations native to the Levant like e.g. the Druze, with some Southerners even plotting with Cypriots (see first attached image). Even on a regional level Italians are easy to tell apart from one another (effectively dividing north, center, south with high accuracy), let alone a native of Spain, Portugal or Southwester France. There is no written history of massive geneflow from Iberia to Italy, so most of the shared ancestry we have must date back to the neolithic and could never be named 'Iberian'.

I will illustrate my point by sharing a few PCA's:

The last one is an example based on my DNA and that of my mom who is fully North Dutch and my father who is fully Neapolitan. As you see, I plot near Northern Italians and Iberians.

They say this calculator (the one AncestryDNA uses) shows ancient ancestry but then again, they'd first have to prove that there was significant geneflow from Iberia to Southern Italy at any moment of history and be justified calling it 'Iberian'. It's mainly with people of mixed background like me, that they have issues with when using this method.
Attached Images
File Type: jpg 377578ejhg2015233x8.jpg (423.7 KB, 10 views)
File Type: jpg PCA (2).jpg (755.5 KB, 9 views)
File Type: jpg 10339517_1420570291546091_5882241668972891718_o.jpg (42.0 KB, 9 views)

Last edited by Dimanto; 4th January 2018 at 08:20 PM.
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  #13  
Old 7th January 2018, 10:38 PM
Germanica Germanica is offline
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I'm not sure how anyone can think that any area in the Mediterranean isn't a neighboring region.
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  #14  
Old 9th January 2018, 07:59 PM
Dimanto Dimanto is offline
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Originally Posted by Germanica View Post
I'm not sure how anyone can think that any area in the Mediterranean isn't a neighboring region.
I will share with you several citations of different scientific articles about the Italian peninsula.

Within Italy

''A correlation between genetic and geographic structure in Europe has also been found, with a detectable distinction between Southern Italians and other Europeans''

''The sensitivity of the clusteralgorithm in assigning each sample to the correct macroarea was 96.43%, 86.55%, 92.00%, 94.44% and 100% for Aosta Valley,Northern Italy, Central Italy, Southern Italy and Sardinia, respectively, whereas the specificity was 98.16%, 96.68%, 94.80%, 99.56% and 100% respectively. In view of the above results, the Italian regions were divided into five groups for the statistical analyses: Northern, Central, Southern Italy, Aosta Valley and Sardinia''

''The genetic distance between Southern and Northern Italians (Fst= 0.0013) is comparable to that between individuals living in different political units (ie, Iberians-Romanians Fst= 0.0011; British-French Fst= 0.0007),and, interestingly, in 450% of all the possible pairwise comparisons within Europe (Supplementary Figure S7).''

The Italian genome reflects the history of Europe and the Mediterranean basin (PDF Download Available). Available from: https://www.researchgate.net/publica...erranean_basin [accessed Jan 10 2018].

Within Spain:

''In general, the Spanish population is similar to the Western and Northern Europeans, but has a more diverse haplotypic structure. Moreover, the Spanish population is also largely homogeneous within itself, although patterns of micro-structure may be able to predict locations of origin from distant regions.''

Now back to answering your comment:

Sure, we Southern Europeans have a shared Sardianian (Neolithic-like) genetic component but originally this came from the East and not from the West; through the northern shores of the Mediterranean, from Greece/Italy and then Spain/Portugal.
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  #15  
Old 11th January 2018, 12:21 AM
PDHOTLEN PDHOTLEN is offline
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Historically, there was a major Spanish military campaign in southern Italy around the time of Columbus. I am fuzzy on the details, but it was competition, I read somewhere, for man power to the Spanish empire in the New World.
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  #16  
Old 11th January 2018, 04:26 PM
Dimanto Dimanto is offline
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Originally Posted by PDHOTLEN View Post
Historically, there was a major Spanish military campaign in southern Italy around the time of Columbus. I am fuzzy on the details, but it was competition, I read somewhere, for man power to the Spanish empire in the New World.
Sure, we had a heavy Aragonese/ Spanish presence in Naples. In case of Naples the soldiers were mostly stationed in the famous Spanish quarters ''quartieri spagnoli'', the Iberians also left the Aragonese castle and also some of the Spanish language seems to have influenced the Neapolitan language. However, no significant geneflow is ever recorded and this is clearly seen in the the present genetic makeup of present day Southern Italians, who don't differ all that much from each other. Also the Aragonese''Iberians'' were mostly perceived as being an opressive foreign force which eventually lead to a revolt lead by Masaniello in 1647.

https://en.wikipedia.org/wiki/Masaniello

https://en.wikipedia.org/wiki/Aragonese_Castle

https://en.wikipedia.org/wiki/Quartieri_Spagnoli

http://www.visitnaples.eu/en/diario-...nguage-naples/

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5434004/

https://en.wikipedia.org/wiki/Aragonese_Castle

Last edited by Dimanto; 11th January 2018 at 04:28 PM.
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  #17  
Old 13th January 2018, 04:09 PM
Germanica Germanica is offline
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Originally Posted by Dimanto View Post
I will share with you several citations of different scientific articles about the Italian peninsula.

Within Italy

''A correlation between genetic and geographic structure in Europe has also been found, with a detectable distinction between Southern Italians and other Europeans''

''The sensitivity of the clusteralgorithm in assigning each sample to the correct macroarea was 96.43%, 86.55%, 92.00%, 94.44% and 100% for Aosta Valley,Northern Italy, Central Italy, Southern Italy and Sardinia, respectively, whereas the specificity was 98.16%, 96.68%, 94.80%, 99.56% and 100% respectively. In view of the above results, the Italian regions were divided into five groups for the statistical analyses: Northern, Central, Southern Italy, Aosta Valley and Sardinia''

''The genetic distance between Southern and Northern Italians (Fst= 0.0013) is comparable to that between individuals living in different political units (ie, Iberians-Romanians Fst= 0.0011; British-French Fst= 0.0007),and, interestingly, in 450% of all the possible pairwise comparisons within Europe (Supplementary Figure S7).''

The Italian genome reflects the history of Europe and the Mediterranean basin (PDF Download Available). Available from: https://www.researchgate.net/publica...erranean_basin [accessed Jan 10 2018].

Within Spain:

''In general, the Spanish population is similar to the Western and Northern Europeans, but has a more diverse haplotypic structure. Moreover, the Spanish population is also largely homogeneous within itself, although patterns of micro-structure may be able to predict locations of origin from distant regions.''

Now back to answering your comment:

Sure, we Southern Europeans have a shared Sardianian (Neolithic-like) genetic component but originally this came from the East and not from the West; through the northern shores of the Mediterranean, from Greece/Italy and then Spain/Portugal.
This is just saying there's a distinction between Northern Italians and Southern, with Northerners being more genetically similar to Northwest Europeans, and that Spain/Portugal is closer to Northwest Europeans too, meaning they are closer to Northern Italians than Southern. So it does not mean that Italians aren't similar to Iberians, just that you're more likely to get Iberian results if you're Northern Italian than Southern. I never specified North or South Italy. Nor does this prove that Italy and Iberia aren't neighboring regions.
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  #18  
Old 17th January 2018, 06:20 PM
Dimanto Dimanto is offline
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Originally Posted by Germanica View Post
This is just saying there's a distinction between Northern Italians and Southern, with Northerners being more genetically similar to Northwest Europeans, and that Spain/Portugal is closer to Northwest Europeans too, meaning they are closer to Northern Italians than Southern. So it does not mean that Italians aren't similar to Iberians, just that you're more likely to get Iberian results if you're Northern Italian than Southern. I never specified North or South Italy. Nor does this prove that Italy and Iberia aren't neighboring regions.
The core disagreement we have is that the percentage of Iberian scored on AncestryDNA by someone of Italian and in my case Southern Italian descent, is easily justified by using arguments like:

Spain is a neighboring region and therefore it's normal for an Italian to score a certain percentage, in the 10-25% range and call it Iberian without giving plausible reasons of how these percentages came to be.

Centuries of Spanish domination existed in Italy and hence we can state that there was much geneflow in Southern Italy coming from Iberia, probably through the soldiers that were stationed in specific area's in the south.
I therefore conclude it is normal for Southern Italians to score a certain amount of Iberian without the need of further empirical evidence to back of my claims.

These tests run on software that use a particular set of reference populations. Sometimes they have issues assigning parts of someone's ancestry to the right region of origins because of the high diversity in haplotypes existing in Southern Italy. For example I score 11% Caucasus which is linked to the genetic region of Southern Italy. Geneflow from the Caucasus to Southern italy goes back thousands of years. The same would be true for Iberia as we can score similar amounts, although Iberia is not being linked to the genetic region of Southern Italy at AncestryDNA. Also I've noticed that individuals of the same region can score varying amounts of Iberian and Caucasus and/or Middle Eastern (similar to GEDmatch' Oracle predictions), while at the same time easily clustering together on a PCA plot. I think when the ethnicity calculators are more matured and have better sampled several regions in Italy, these absurdly high percentages of Iberian will disappear, just like they have on 23andme's Ancestry Composition.

You could try to experiment with MyHeritage's ehtnicity calculator by uploading several kits from different companies and look at the varrying results you'll get. On one occasion I get 56% Italian, some Ashkenazi Jewish and West Asian - on the other 52% Italian with almost 5% North African and even an additioal 0.7% West African, while no other test ever gave me anything near SSA. On FTDNA I get 38% Southeast Europe, 8% East Europe, 3% Jewish diaspora and 2% Asia Minor. The Southeast European is the only estimation that seems allright given the strong similarities between Southern Italians and those from the Southern Balkan and Greece.

Last edited by Dimanto; 17th January 2018 at 06:47 PM.
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