Y-chromosome analysis recapitulates key events of Mediterranean populations

Tautalus

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Portuguese
Y-DNA haplogroup
I2-M223 / I-FTB15368
mtDNA haplogroup
H6a1b2
Abstract
The remarkable geographical situation of the Mediterranean region, located between Europe, Africa, and Asia, with numerous migratory routes, has made this area a crucible of cultures. Studying the Y-chromosome variability is a very performant tool to explore the genetic ancestry and evaluate scenarios that may explain the current Mediterranean gene pool. Here, six Mediterranean populations, including three Balearic Islands (Ibiza, Majorca, and Minorca) and three Southern Italian regions (Catanzaro, Cosenza, and Reggio di Calabria) were typed using 23 Y-STR loci and up to 39 Y-SNPs and compared to geographically targeted key reference populations to explore their genetic relationship and provide an overview of Y-chromosome variation across the Mediterranean basin. Pairwise RST genetic distances calculated with STRs markers and Y-haplogroups mirror the West to East geographic distribution of European and Asian Mediterranean populations, highlighting the North-South division of Italy, with a higher Eastern Mediterranean component in Southern Italian populations. In contrast, the African populations from the Southern coast of the Mediterranean clustered separately. Overall, these results support the notion that migrations from Magna Graecia or the Byzantine Empire, which followed similar Neolithic and post-Neolithic routes into Southern Italy, may have contributed to maintaining and/or reinforcing the Eastern Mediterranean genetic component in Southern Italian populations.

https://www.cell.com/heliyon/fulltext/S2405-8440(24)11360-6

38 geographically targeted key reference populations employed in this study. Populations are represented by dot and an abbreviation. Spain: ARA (Aragon), BCN (Barcelona), IBI (Ibiza), MAJ (Majorca), and MIN (Minorca). France: MARS (Marseille) and TOU (Toulouse). Italy: BELV (Belvedere), CATA (Catania), CTR (Catanzaro), CSZ (Cosenza), EMIROM (Emilia-Romagna), SPEZ (La Spezia), LAT (Latium), LIG (Liguria), MAR (Marche), OFF (Offida), PUG (Puglia), RAV (Ravenna), RC (Reggio di Calabria), SIC (Sicily), TRAP (Trapani), TUSC (Tuscany), UDI (Udine), and VENE (Veneto). Greece: ATHE (Athens) and GRE (Greece). Cyprus: CYP (Cyprus). Lebanon: LEBA (Lebanon). Turkey: ATURK (Aegean Turkey Region), MATURK (Marmara Turkey Region), and METURK (Mediterranean Turkey Region). Algeria: ORA (Oran). Tunisia: SOUS (Sousse). Libya: BANG (Banghazi), LIB (Libya), and TRIP (Tripoli). Egypt: NEGY (Northern Egypt).
H4ggUTV.png


Multidimensional scaling (MDS) analysis based upon pairwise genetic distance show differences among populations:
OoePu5u.jpg


Graphic representation of the migration histories derived from the data generated in this study:


llwnlJq.png
 
To me it is surprising if there were such a huge difference in Y-DNA distribution to conclude that the Tuscans and the Romagnoli are "Western Mediterraneans", while their neighbours from Marche and Lazio (which would appear even more "eastern" that Sicily) are "Eastern Mediterraneans".

At least I'm not aware about these regions having such different patterns of human migrations to explain these different labels.
 
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To me it is surprising if there were such a huge difference in Y-DNA distribution to conclude that the Tuscans and the Romagnoli are "Western Mediterraneans", while their neighbours from Marche and Lazio (which would appear even more "eastern" that Sicily) are "Eastern Mediterraneans".

At least I'm not aware about these regions having such different patterns of human migrations to explain these different labels.

The idea that in Italy there is, in addition to a north-south cline, also a west-east cline has been argued for years on the basis of uniparental markers, specifically Y-chromosome analysis. Thus, as it is known that more R1b exists in Tuscany, based on academic samples, than in Marche or Lazio. I haven't read this study yet, but it should be taken for what it is.
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This is a 2013 study.

Geographical patterns of sPC1 and sPC2 are plotted in Figure 1. sPC1 identifies two main groups of populations separated by an almost longitudinal line (Figure 1a). The first group (black squares) is represented by populations from North-Western Italy, including most of the Padana plain and Tuscany. The second group (white squares) includes locations from South-Eastern Italy and the whole Adriatic coast, being represented also in North-Eastern Italy.

 
In this latter study North-Eastern Italy lies comfortably in the "western" group though.
 
In respect to the study linked in the OP: I find these labels arbitrary and of little informative value (if not possibly misleading): what's the point of having, for example, the Tuscans in a "Western" group and the people from Marche in an "Eastern" group when in fact they are genetically closer to each other than they are, respectively, to the Balearics (the Tuscans) and to the Turks (the Marche sample)?

Besides the distribution in the "Eastern" group would vary enormously. The Y-DNA haplogroups distribution in, say, Lazio is nothing like the Y-DNA haplogroups' breakdown of Cyprus or Anatolia.

Bottom line, in my opinion, if you are going to group human populations in order to give them labels, which inevitably end up suggesting some level of genetic homogeneity between members of a same "group", at least make sure you are using autosomal DNA and not uniparental markers.
 
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Interesting to confirm, once more, how relevant is the presence of J2a-Z387 in Calabria, and among J2a's in the Balearic islands, probably most of them J2-L70.
A clear northern Mediterranean subclade of J2a, as hypothesized on other papers.
 
This is a limitation of this type of analysis, it only represents a small fraction of the genome.
However it is useful for studying male-specific migration patterns and historical population movements.


The classification of some regions like Lazio as "Eastern" is strange, isn’t R1b the major haplogroup in that region?

Maybe a map like this represents better the distribution of the Italian y-chromosome.
(clicking on the map takes you to the original study)

 
The classification of some regions like Lazio as "Eastern" is strange, isn’t R1b the major haplogroup in that region?

In Lazio and Marche R1b decreases a lot compared to Tuscany and Emilia-Romagna. According to Maciamo's data from academic studies in Lazio R1b is 29%, in Marche R1b is 34%, compared to 52.5% in Tuscany and 53.5% in Emilia-Romagna. It should be mentioned that not all clades of R1b can be considered "western."

NNJI18M.jpeg
 
In Lazio and Marche R1b decreases a lot compared to Tuscany and Emilia-Romagna. According to Maciamo's data from academic studies in Lazio R1b is 29%, in Marche R1b is 34%, compared to 52.5% in Tuscany and 53.5% in Emilia-Romagna. It should be mentioned that not all clades of R1b can be considered "western."
At 29%(Lazio) and 34%(Marche) they are the most frequent haplogroups, but has you said not all R1b clades are considered “Western”, like for example R-PF7562 and some clades of R-Z2103.

Do you know if exist One similar article with forefathers of Iberia?
Kirgonix, I don't know of any article or site with similar information for Iberia.
 
In respect to the study linked in the OP: I find these labels arbitrary and of little informative value (if not possibly misleading): what's the point of having, for example, the Tuscans in a "Western" group and the people from Marche in an "Eastern" group when in fact they are genetically closer to each other than they are, respectively, to the Balearics (the Tuscans) and to the Turks (the Marche sample)?

Besides the distribution in the "Eastern" group would vary enormously. The Y-DNA haplogroups distribution in, say, Lazio is nothing like the Y-DNA haplogroups' breakdown of Cyprus or Anatolia.

Bottom line, in my opinion, if you are going to group human populations in order to give them labels, which inevitably end up suggesting some level of genetic homogeneity between members of a same "group", at least make sure you are using autosomal DNA and not uniparental markers.

You seem to be confusing uniparental markers with autosomal DNA. The study posted by the OP is based only on uniparental markers and specifically on the Y chromosome. What this study supports was already supported by Boattini in 2013, albeit with different multivariate statistical tools. One only has to take the data collected by Maciamo to see that this study does not support anything controversial. The study clearly says that the divisions are based on Y-DNA, there can be no misunderstanding. Obviously like all divisions even the west-east one should be taken for what it is, all divisions are arbitrary. The west-east division is only functional to reconstruct human movements in this case. Being eastern is not a disgrace, and eastern is a broader concept than Middle-East in this case.

Regarding the closeness between Tuscans and Marche people, in Raveane 2019, which is the most comprehensive study published to date on Italians based on autosomal DNA, Tuscans and Marche people end up in two different clusters. Tuscans end up in the northern-central cluster and Marche people in the southern-central cluster. The misunderstanding is based on the idea that statistical-geographic divisions then correspond exactly to genetic clusters. This is not always the case, because genetically, in addition to a north-south cline, there is also a slight west-east cline, as already mentioned. There is really a strong closeness between people from the Marche, Umbria and Lazio; the Tuscans, on the other hand, are closer to Emilia, or as Angela said already 6/7 years ago are intermediate between northern and central Italy. No surprise, they are also geographically closer to Emilia (we still lack data on the Romagna autosomal but a sample from Ravenna appears in this study that is similar to Tuscany in Y-DNA).

s58YFip.jpeg


These PCAs are based on K12b and say nothing different from what Raveane 2019 claims.

kUWRAf8.png


edLjbCR.png
 
At 29%(Lazio) and 34%(Marche) they are the most frequent haplogroups, but has you said not all R1b clades are considered “Western”, like for example R-PF7562 and some clades of R-Z2103.

Exactly, not all R1b are considered "western" and for an MDS plot evidently that 34/29% is not enough, which then will be less if we consider only the really western ones. it is obvious that then there would be to go into the details of the data, but as I wrote before west-east division is only functional to reconstruct human movements in this case.
 
You seem to be confusing uniparental markers with autosomal DNA. The study posted by the OP is based only on uniparental markers and specifically on the Y chromosome. What this study supports was already supported by Boattini in 2013, albeit with different multivariate statistical tools. One only has to take the data collected by Maciamo to see that this study does not support anything controversial. The study clearly says that the divisions are based on Y-DNA, there can be no misunderstanding. Obviously like all divisions even the west-east one should be taken for what it is, all divisions are arbitrary. The west-east division is only functional to reconstruct human movements in this case. Being eastern is not a disgrace, and eastern is a broader concept than Middle-East in this case.
That was really not my intention, I apologise for not being clear enough. As a matter of fact, in my previous post, I highlighted that this sort of "eastern"/"western" grouping, in my opinion, provides valuable information only to the extent that it is based on autosomal DNA rather than uniparental markers. In fact I find conclusions based on Y-DNA alone more shaky and more easily subject to manipulation by people with agendas.

We agree that all divisions of this kind are arbitrary, this one, at least to me, more than others. It's a matter of method (i.e. forced arbitrary labelling) to me, not of validity of results. I hope it makes sense what I'm trying to say.

Regarding the closeness between Tuscans and Marche people, in Raveane 2019, which is the most comprehensive study published to date on Italians based on autosomal DNA, Tuscans and Marche people end up in two different clusters. Tuscans end up in the northern-central cluster and Marche people in the southern-central cluster. The misunderstanding is based on the idea that statistical-geographic divisions then correspond exactly to genetic clusters. This is not always the case, because genetically, in addition to a north-south cline, there is also a slight west-east cline, as already mentioned. There is really a strong closeness between people from the Marche, Umbria and Lazio; the Tuscans, on the other hand, are closer to Emilia, or as Angela said already 6/7 years ago are intermediate between northern and central Italy. No surprise, they are also geographically closer to Emilia (we still lack data on the Romagna autosomal but a sample from Ravenna appears in this study that is similar to Tuscany in Y-DNA).
Again, that was not my point. I just meant what I wrote, i.e. that the Tuscans and the people of Marche are genetically closer to each other than they are to most populations in their respective arbitrarily separated "Western" and "Eastern" group.

This, to me (but again it's just my opinion to which I'm fully entitled), makes this excercise in labelling 1. devoid of a real genetic-anthropologic meaning and, worse 2. subject to a concrete danger of manipulation especially elsewhere not in this forum.
 
s58YFip.jpeg


These PCAs are based on K12b and say nothing different from what Raveane 2019 claims.

kUWRAf8.png


edLjbCR.png
To better explain my point of view.

What someone might see (mind you, equally arbitrarily) in those plots is that a third group exists: the "Central", roughly equidistant between the "Western" and "Eastern" groups.

It depends on what is my interpretation and my interpretation an awful lot of times is biased by what I set out to prove from the very beginning.

As a Northern Italian (very much so in favor of a united Italy) I'm sorry to say that the general tone of most conversations bringing in the "Western" and "Eastern" labels is an underlying dog whistle for trolls: "Western = pure European / Eastern = not really European" (so you'll pardon me if grouping Marche and Lebanon together rang a bell for my very personal sensibility).
 
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That was really not my intention, I apologise for not being clear enough. As a matter of fact, in my previous post, I highlighted that this sort of "eastern"/"western" grouping, in my opinion, provides valuable information only to the extent that it is based on autosomal DNA rather than uniparental markers. In fact I find conclusions based on Y-DNA alone more shaky and more easily subject to manipulation by people with agendas.

We agree that all divisions of this kind are arbitrary, this one, at least to me, more than others. It's a matter of method (i.e. forced arbitrary labelling) to me, not of validity of results. I hope it makes sense what I'm trying to say.


Again, that was not my point. I just meant what I wrote, i.e. that the Tuscans and the people of Marche are genetically closer to each other than they are to most populations in their respective arbitrarily separated "Western" and "Eastern" group.

This, to me (but again it's just my opinion to which I'm fully entitled), makes this excercise in labelling 1. devoid of a real genetic-anthropologic meaning and, worse 2. subject to a concrete danger of manipulation especially elsewhere not in this forum.
To better explain my point of view.

What someone might see (mind you, equally arbitrarily) in those plots is that a third group exists: the "Central", roughly equidistant between the "Western" and "Eastern" groups.

It depends on what is my interpretation and my interpretation an awful lot of times is biased by what I set out to prove from the very beginning.


In my opinion you are projecting too much onto these west-east divisions, giving too much weight to trolling in the forums, as if being in an eastern cluster for an Italian is some kind of racial offense. That there is not only a north-south cline but also a west-east cline, even on the basis of autosomal DNA not just uniparental markers, just see Raveane's 2019 PCA, is a fact. Whether this study is really a masterpiece of population genetics is another matter.
 
From the paper:

In Italy, subhaplogroup E1b1b-V13 appears with higher frequency than in Spain. This subhaplogroup is distinctive in the Balkan Peninsula, particularly in Greece, and serves as a marker for assessing the Hellenic influence in the Mediterranean [14,15]. Several evidences suggest an initial migration of E1b1b-V13 from Anatolia to the Balkans, where it expanded demographically and then spread to Southern Italy [30,47,48]. However, the occupation by the Hellenes of Magna Graecia from the 8th century BC [14,15,30] and the fluid contact between Southern Italy and the Greek areas even during the time this region was under the dominion of the Crown of Aragon (12th to 18th centuries) [49,50], may have helped to maintain and/or reinforce the presence of this subhaplogroup in Italy. In fact, before the Roman Empire, one in every 10–13 inhabitants in Southern Italy was Greek [35]. Hence, it makes sense that E1b1b-V13 is mainly found in Catanzaro, Cosenza and Reggio di Calabria populations.
 
From the paper:

In Italy, subhaplogroup E1b1b-V13 appears with higher frequency than in Spain. This subhaplogroup is distinctive in the Balkan Peninsula, particularly in Greece, and serves as a marker for assessing the Hellenic influence in the Mediterranean [14,15]. Several evidences suggest an initial migration of E1b1b-V13 from Anatolia to the Balkans, where it expanded demographically and then spread to Southern Italy [30,47,48]. However, the occupation by the Hellenes of Magna Graecia from the 8th century BC [14,15,30] and the fluid contact between Southern Italy and the Greek areas even during the time this region was under the dominion of the Crown of Aragon (12th to 18th centuries) [49,50], may have helped to maintain and/or reinforce the presence of this subhaplogroup in Italy. In fact, before the Roman Empire, one in every 10–13 inhabitants in Southern Italy was Greek [35]. Hence, it makes sense that E1b1b-V13 is mainly found in Catanzaro, Cosenza and Reggio di Calabria populations.
My estimation for Greeks being the majority in Sicily and Calabria in 5th century BC (which did decrease with Romans genociding them and wiping off Carthage completely too) and possibly around 20% in Basilicata, Campania and Apulia was actually very high compared to academics putting the number at 10%.

Angela dogpiled me for giving those generous numbers where they were far better than the official Italian academics estimating only 10%.
(10% is very low to be accurate but still)
 
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Also Peloponnesians are completely different from Calabrese Y-DNA wise. Especially Western Peloponnesians. Wouldn't be surprised if the study in 2017 had Y-DNA results but they did not publish those because of the high difference in J2a dominating Deep Mani and Sicily compared while E-V13 dominating Peloponnesians.

Sorry, not sorry.
 
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The foreign R1b elite almost annihilated the male lineages of the Mesolithic and Neolithic among the Basques. Initially they entered stealthily and later, in the Iron Age, they became more intense. What is striking is that the Basques are ethnically those who most closely resemble the natives of the Iberian Peninsula of the Stone Age. The foreigners must have been men with many wives and the local men must have been harshly subjugated, including in terms of reproductive issues. Life in those times was tough.
 
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