November 26, 2011

mtDNA of Venezuelans

Am J Phys Anthropol DOI: 10.1002/ajpa.21629

A melting pot of multicontinental mtDNA lineages in admixed Venezuelans

Alberto Gómez-Carballa et al.

The arrival of Europeans in Colonial and post-Colonial times coupled with the forced introduction of sub-Saharan Africans have dramatically changed the genetic background of Venezuela. The main aim of the present study was to evaluate, through the study of mitochondrial DNA (mtDNA) variation, the extent of admixture and the characterization of the most likely continental ancestral sources of present-day urban Venezuelans. We analyzed two admixed populations that have experienced different demographic histories, namely, Caracas (n = 131) and Pueblo Llano (n = 219). The native American component of admixed Venezuelans accounted for 80% (46% haplogroup [hg] A2, 7% hg B2, 21% hg C1, and 6% hg D1) of all mtDNAs; while the sub-Saharan and European contributions made up ∼10% each, indicating that Trans-Atlantic immigrants have only partially erased the native American nature of Venezuelans. A Bayesian-based model allowed the different contributions of European countries to admixed Venezuelans to be disentangled (Spain: ∼38.4%, Portugal: ∼35.5%, Italy: ∼27.0%), in good agreement with the documented history. Seventeen entire mtDNA genomes were sequenced, which allowed five new native American branches to be discovered. B2j and B2k, are supported by two different haplotypes and control region data, and their coalescence ages are 3.9 k.y. (95% C.I. 0–7.8) and 2.6 k.y. (95% C.I. 0.1–5.2), respectively. The other clades were exclusively observed in Pueblo Llano and they show the fingerprint of strong recent genetic drift coupled with severe historical consanguinity episodes that might explain the high prevalence of certain Mendelian and complex multi-factorial diseases in this region.

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21 comments:

Pascvaks said...

Am I wrong to assume that "admixed" here means "Native American + whatever" and this does not represent the country's population as a whole? Nor the "Native Only" population, merely the "Native admixed"?

Maju said...

And this is one of the most intensely colonized Hispanic-American lands. So where is the 80% native mtDNA of Europeans, Dienekes? ;)

Dienekes said...

And this is one of the most intensely colonized Hispanic-American lands. So where is the 80% native mtDNA of Europeans, Dienekes? ;)

The colonization of North America by Europeans forms a much better analogy to the prehistoric colonization of Europe by people from Asia: first, North America was sparsely populated and included (at least in the US and Canada) largely groups of hunters; second, the colonization included family units, whereas in South America there was male-mediated gene flow; third, the colonists of North America largely avoided intermingling with the Native Americans, which is precisely what we see in Europe (G2a-rich/U-deficient folk everywhere we look).

The situation in Latin America more resembles that of the Indian subctontinent, in that there were solid large native agricultural populations and a policy of incorporation which ended up in a whole spectrum of individuals of varying degrees of Caucasoid ancestry, and a caste system built around this (formal in South Asia, informal in most of Latin America).

Dienekes said...

I forgot to mention the role of climate; Caucasoids do not flourish in the equatorial regions, and it is no accident that the Caucasoid element in the Americas has a U-type distribution, being highest in places like Canada/US and Argentina, and lowest in Central America.

Maju said...

And you forgot the industrial capacity to transport people by thousands and even millions right into destination, and you forgot the Magdalenian population explosion, and that even at their peaks, Neolithic populations are some 5 times Epipaleolithic ones (and not a million times), and you forgot that your dear G2a is rather rare today, etc.

Dienekes said...

G2a was the first wave.
J2 and R1 came later.

Also, the capacity to transport people to their destination was necessary in the case of the Americas, because it involved an ocean voyage. Humans had the capacity to get into Europe by the maritime route since the Upper Paleolithic, and, of course, they could have walked there, while the distances are much smaller.

In any case, you can go on believing your theory of Paleolithic continuity, the data is already accumulating and every single datapoint (from the Mesolithic mtDNA, the Neolithic Y-chromosomes, and the first hints of Oetzi's autosomal DNA) points to discontinuity.

Baldric said...

Be very weary with this studies. Coming from Venezuela, there is ZERO chance that this is not politically motivated. All conquerors had sons with the only women available, so many autosomally mestizos are shown as natives.

The same goes for the African element. It is IMPOSSIBLE for the overall contribution of african genes to the venezuelan genepool to be only 10%. This happens because male slaves were more common than female slaves.

To sum up: mtdna without Y-dna is worthless to study the present genetic makup of a population.
Wither work with autosomal or with both unrecombinables.

Pascvaks said...

I've learned so much since droping by a few weeks ago. So very interesting. Had the impression the European mix was much higher.

Ricardo Costa de Oliveira said...

I am not a specialist in the Hispanic history of Venezuela but in the Brazilian Portuguese Empire the Conquistadores kept the same Ethno-National Project building a new American version of our same Language, Religion, Culture, Military and State with the moving frontiers since the River Douro. The difference was quantitative, you had almost 70 million of poor semi-starving European migrants or protestant religious refugees to North America and the Elite Dominance of a group of the Brazilian Portuguese Colonial Elite of 1 million in Colonial Brazil that could expand to the majority dominance of 50 times of their Colonial Y DNA combined with the Brazilian mtDNA racial democracy in the conquest and colonization of the big Brazilian territory operating the Imperial Slavery and remember that after 1850 Brazil also joined the migration modal so we can have several places and regions like Porto Alegre with almost 70% of Eurasian mtDNA as we can see in the SuppInfo3. And I will bet in our South American Project in this new Century in face of the United States and Euro current models…

Onur said...

Had the impression the European mix was much higher.

It must be so in autosomes and especially Y-chromosomes.

Roy said...

Maju, where were the great sugar plantations in Venezuela? Surely its jungles were less attractive to slavers than the Caribbean islands of Cuba or Hispaniola.

South Central Haplo said...

"The situation in Latin America more resembles that of the Indian subctontinent, and varying degrees of Caucasoid ancestry, and a caste system"

Dienekes You are using this worn out Gramophone record for long. How can you be so sure?. In Pakistan mt haplo M is 50% and in high altitude fair skinned Kashmir mt M is > 60%. somebody said in Afghanistan it is 30-40%.

Also Majority of Untouchable people of North India are Y R1a. Historical migrations are not as male dominated as North American settlements. Caucasoid ancestry is not applicable to India. These are paleolithic continuation of ANI. India has more mt U compared to middle east. you need to consider that. ANI spread upto Afghanistan.
ANI, central Asia are close to each other .

hailtoyou said...

"A credible break-down [for Venezuela] through 1990 would be 68 percent mestizo, 21 percent unmixed Caucasian, 10 percent black, and 1 percent Indian." ("Venezuela, a Country Study", c1990).

The study-authors use the term "admixed Venezuelans". I presume this means that the population under study is the 68%-Mestizo category?

eurologist said...

These are paleolithic continuation of ANI.

Yes, largely; I share that view.

G Horvat said...

The Caracas sample size is indicated as being "131" in the abstract but there are only 31 lineages from Caracas listed in the supplementary file (!?!?)

More interesting to me than the admixture levels are the D4h3a sequences in the Pueblo Llano sample.

Kepler said...

I am Venezuelan.
Perhaps you can be interested in checking out this article from 2007:

http://goliath.ecnext.com/coms2/gi_0199-7152117/Admixture-estimates-for-Caracas-Venezuela.html

Autosomal markers:

private clinic (better-off people)
"European": 75%
native American: 16%
sub-Saharan: 8%

public hospital:
European: 0.32%
native American: 39%
sub-Saharan: 27%

Y haplogroups:

private clinic
"European"92%
native American: 0%

public hospital:
"European" 84%
native American: 7%

mDNA:

private clinic:
of European origin: 49%,
of native American: 43%
of sub-Saharan: 8%

public hospital
of European origin: 14%,
of native American: 72%
of sub-Saharan: 14%

I disagree with Maju. There were other places with more Spanish settlement: Argentina, Chile, Uruguay, Mexico (although Mexico had many more native Americans).


I have mentioned this before: I have J2 on the male side and L1c3 on the mtDNA. My mother looked like a Galician woman (freckles, very white), but then her father was blond and blue-eyed. My grandmother looked darker but more like a mestiza (indian eyes, European nose), from poor background, village.
So: the mixture is huge.
Obviously my greatgreatgreatgrandmother seems to have been a slave from Western Africa.

I come from Valencia, close to the coast.

Pueblo Llano is a tiny region in the Andes with very little immigration after the Conquista.

When the Conquista started, the coast and the Andes were relatively densely populated, but the aniquilation and mixing was huge.
A lot of Spaniards practiced massive raping, others simply had a lot of "mistresses", who saw it convenient to have mestizos instead of indios as children.

There is also a third of Venezuela which was settled only very late, because of the climate: the Llanos in the centre.
That region is flat, very dry in "summer" and flooded in the rainy season, where little agriculture was possible earlier.
The indian population there was rather very scarce, unlike at the coast or in the Andes.
Again: in the Andes and coast mixing came in very fast.

South of the Orinoco, where a minority of the population lives, got even less migration. The vast majority of the population lives in the coast and some in the bigger cities of the Andes and a couple of cities in the northern Llanos.
Now, I would have considered more interesting if they had measured mtDNA from an average urban centre in Venezuela. This is something few grasp: most people in Venezuela (70%) live in cities of more than 100000 inhabitants but less than a million.
The dynamics are completely different.

Unfortunately, these studies seem to go either for Caracas or for villages in the middle of nowhere.

Kepler said...

Something else: that study about ethnic groups in Venezuela is quite similar to other "studies" from the whole XX century. I honestly doubt we can talk about 20% "unmixed" Caucasoid. If your great-grandparents were born in Venezuela, I very much doubt you don't have some mix. That's the way it goes in Venezuela, the mixing was higher than in societies such as Peru's, for instance.

Foreigners have just copied those numbers from earlier studies. Alexander von Humboldt, 200 years ago, had quite similar numbers, only with a higher proportion of native Americans (like 10%).

Another thing is the proportion of 'Portuguese', 'Italian', compared to Spanish. That's just wrong. Before 1950 there was very little immigration from either Portugal or Italy. A very small Portuguese immigration occurred particularly in the late XVI and start of the XVII centuries. Massive immigration from Portugal and Italy started from 1950.
Spanish immigration kept going from the beginning...although there were times when few came (almost all men), it went through since 1498...when Italiand and Portuguese were immigrating in the second half of the XX century, Spaniards were doing the same...just up to the early eighties, when European migration went dramatically down.

hailtoyou said...

Kepler,
Why has Venezuela not counted people by race since the 1920s?

I can understand why Chavez would not. Why have none of his predecessors, since the era when Madison Grant and Hans Guenther were mainstream/acceptable writers on Race?

Kepler said...

Hailtoyou,

Oh, I see you are obsessed with the "white" in danger in the USA and the rest of the world...you have a pretty racialist blog.

About your question: Why should we? It is Chávez who has re-introduced some form of ethnic counting by asking for "ethnicity" in some forms. He thrives on racism, like others.

Most Venezuelans find that silly and it has been so for decades. Why? We are almost all mixed and almost all in every form, not just recent "white"/"black".
20% "white"? 10% My foot.

When are you "black"? With 20% of sub-Saharan background? 10%? 50%?
51%? When white? With 100% only? Or according to a Ariernachweis?

Most of us could say almost all our 8 great-grandparents were mixed-raced in one way or the other.

Few countries outside the US are so keen on counting people according to some "race". Russians are thinking about reintroducing the ethnicity in their passport. Rwanda used to have that ages until some years ago.

hailtoyou said...

Kepler wrote:
"Chávez..has re-introduced some form of ethnic counting by asking for "ethnicity" in some forms"

I did not know that. What are the results?

There is always social value in finding out numbers for self-identified ethnicities/races.

For instance, we always hear that the opposition to Chavez is wealthier and white, while Chavez' support comes from poor Blacks, Mulattoes, Mestizoes (who are a majority). Determining the share of people who think of themselves as Whites is useful for political analysis.

Kepler said...

"What are the results?"
Nobody knows. Those were for some projects to state moneys or to get registered in some classes or for scholarships. The educational offer from the state is getting worse by the day. Most Venezuelans find the filling in of forms about ethnicity a little bit weird. I have mixed ancestry from Europe, native America and Africa and I considered myself mixed, but so do I 99% of all Venezuelans. Most people in Europe consider I am "white".
Within my own extended family you find every shade and colour and that's true for most Venezuelans.

Perhaps with one of these Dienekes measurements on skull, nose, etc, I can see if there is some pattern popping up.


Right now some of the wealthiest Venezuelans are Chavistas (the Boliburguesía), but also some of the poorest.

The issue is that we don't have any more just "mestizos" (Indian-European) or mulatos" (black-European) or "zambos" (Indian-black) but the product of a mestizo and a mestiza and crossing that with an European and then a zambo and then two Europeans and then two mestizos and and and and...and that is almost in every Venezuelan family but for 1) very isolated villages (and Pueblo Llano belongs to that category), 2) some areas close to the coast, like near the Caracas airport (and where foreign journalists always go), where there were big slave haciendas and a large proportion of black and 3) in the very sparcely populated areas of Amazonas and Delta Amacuro.

But things are complexer now: the Warao indians in Delta Amacuro are still very much for Chavez, but the Carib and Arawak Indians in Amazonas are not and things are changing in the Wayuu area (also Arawak).

There are several thousand refugees from Southeastern Colombia who belong to the Inga tribe and who were very close to FARC and who migrated to Venezuela recently. They are very Chavistas and they were given the Venezuelan nationality now. They have also beeen recognized as "Venezuelan originary tribe" even if they just arrived some years ago...just because they vote for Chávez.

More interesting than determine the share of white or poor is determining why some very poor areas and also areas where darker skinned people are abundant now are against Chávez.