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Humanist
07-02-2014, 07:41 AM
Reading up on the Basques a bit, I was surprised to learn the following:


The Basques stand out from the rest of Europe by their exceptionally high frequency of haplogroup H (61.5%, including 44% of H1 and H3)...

Source: Eupedia (http://www.eupedia.com/forum/threads/26805-New-mtDNA-amp-Y-DNA-frequencies-for-the-Basques)

Can anyone recommend any comprehensive studies on Basque mtDNA? In particular, I am interested in learning which varieties of H, apart from H1 and H3 are frequently observed in the Basques.

Jean M
07-02-2014, 10:41 AM
Here is my section on Basque mtDNA from Ancestral Journeys:


Much was made in early papers of the supposed absence in the Basque population of mtDNA J (a Neolithic marker). More recent studies found haplogroup J in both French and Spanish Basques. Another popular theory was that the density of mtDNA haplogroups H1 and H3 in Iberia and particularly among the Basques reflects the Mesolithic re-colonisation of Europe from the Franco-Cantabrian glacial refuge. Yet the greatest diversity of H3 is in north Africa, and that for H1 in the Near East. That suggests that both arrived with early farmers. H1 and H3 show a low diversity among the Basques.

Curiously an mtDNA haplogroup that appears in only a small proportion of Basques is the most revealing clue to the Copper Age component. The rarity of HV4a1 makes its history easier to trace. HV4a1 has a sister in the Near East, HV4a2, which makes it likely that HV4a arose there. One branch of HV4a appears to have entered Eastern Europe, where HV4a1 arose. Tracking its movements through modern populations we reach Italy and then southwestern France, where HV4a1a appeared at an estimated 3400 BC. HV4a1a is certainly most diverse in the Franco-Cantabrian region. It generated at least three subclades in this area. Its highest density today is in the Spanish Basque Country. So it looks distinctively Basque. If the dating is correct, it suggests a movement from somewhere in eastern Europe to southwestern France in the Copper Age....

The Basques are a people with their own genetic footprint. Still they are a modern people, not an ancient one miraculously preserved. So we should expect them to be a genetic mixture, as all Europeans are, rather than 100% pure descendants of the artists of Lascaux. They could be the product of layer upon layer of peoples sheltering in the shadow of the northern Pyrenees. Their high level of mtDNA U5b hints at Mesolithic hunters. Their Y-DNA I2a1a (M26) and perhaps E-V12* appear to link them to the strand of early farmers noted for Cardial Ware. Certainly Cardial Ware moved up the Garonne from the Mediterranean to what is now Gascony. Copper Age arrivals could have added another ingredient to the mix – the predominant Y-DNA R1b1a2. One study of a set of Basque R1b1a2 carriers calculated an expansion in the Basque population around 5500 BC coupled with a very high population growth rate. Given the uncertainties of the dating process, that might indicate either a Neolithic or a Copper Age expansion from a tiny founding group.

Jean M
07-02-2014, 11:11 AM
From https://www.familytreedna.com/public/u5b/default.aspx?section=results

In a 2012 study of the Basque region by Behar et al, 12% of the Basques are in haplogroup U5b1f1a, while another 5% are in other subclades of U5.


The study in question: Doron M. Behar et al., The Basque Paradigm: Genetic Evidence of a Maternal Continuity in the Franco-Cantabrian Region since Pre-Neolithic Times, The American Journal of Human Genetics, Volume 90. http://www.ncbi.nlm.nih.gov/pubmed/22365151 [Open access]

They sequenced 420 complete mtDNA genomes, focusing on haplogroup H.


We identified six mtDNA haplogroups, H1j1, H1t1, H2a5a1, H1av1, H3c2a, and H1e1a1, which are autochthonous to the Franco-Cantabrian region and, more specifically, to Basque-speaking populations. We detected signals of the expansion of these haplogroups at ~4,000 years before present (YBP) and estimated their separation from the pan-European gene pool at ~8,000 YBP, antedating the Indo-European arrival to the region.

dp
07-18-2014, 05:54 PM
Gonzalez in a 2006 paper found one Basque, listed as from Iberian provinces (Spain) that placed in mtdna haplogroup K1a1b1-C5742T T15074C, using RSRS as the reference. The sequence is on GEDBANK as DQ200804.
In other words not all Basques are in H. Some are from K, which is off of U8.
David Powell
dp :-)

Erik
07-18-2014, 06:48 PM
They are thought to be the first settlers of Europe, according to certain theories. Since they are distinct from other Europeans, I wonder what a "pure-blooded" Basque's results would be on an autosomal test such as AncestryDNA that doesn't have a Basque category.

dp
07-18-2014, 07:29 PM
My original post was in the line of trivia. But I've now found my copy of Ana M. Gonzalex's (2006) paper. It's entitled "The mitochondrial lineage U8a reveals a Paleolithic settlement in the Basque country". Out of a sample of 211 unrelated (mtdna) Basques they found 4 Basques that placed in U8. Of those there was the one I already mentioned in the daughter branch of U8b/K, one in U8a*, and two in U8a1. They added other U8a's from published data and got a coalescence for the haplogroup of 37,000 +/- 14,000 ybp. Therefore, the U8a Basques (or some of them) are of Paleolithic stock.
David Powell
dp :-)
PS: no idea on the autosomal lines :-)

GailT
07-18-2014, 10:41 PM
I'm curious to know what Bill thinks about the origins of U8a. Behar has an age estimate of 18,500 years. I looked at some of the samples in GenBank and it does seem to have a western and northern European distribution, so perhaps it expanded from an LGM refuge. The problem is there are very few samples in the older branches which makes it difficult to look at its ancient variability.

The problem with the Gonzales paper (and many others) is that they indulge in extremely naive phylogeographic analysis. You can't say anything at all about when and where a population originated by looking at the modern distribution of just a few samples. U5 is also found in the Basque, but if you exclude a recent founder effect in U5b1f1a, the U5 distribution of the Basque is very similar to others areas in southern Europe. So the fact that we find U5 or U8 samples among the Basque isn't telling us anything about their ancient origins, except that they are similar to other Europeans. The autosomal DNA would be a more useful approach.

Jean M
07-18-2014, 11:37 PM
The autosomal DNA would be a more useful approach.

That approach has been taken, along with just about any other that any geneticist can think of. The Basques are one of the most studied populations in Europe, precisely because of this decades-old idea (now in tatters) that they are a palaeolothic relic. I didn't want to highjack a thread on mtDNA with all the other genetic studies of the Basques. But in brief from AJ:


A genome-wide study of Spanish Basques did not find them particularly differentiated from other Iberian populations. [Laayouni, Calafell and Bertranpetit 2010.] A similar study redressed the balance. The French and Spanish Basques do form an homogeneous group, which can be distinguished from non-Spanish European populations (such as French and Sardinian) to roughly the same degree that those populations can be distinguished from each other. [Rodríguez-Ezpeleta 2010.]


The Basques have been included in more recent full-genome comparisons, such as Lazaridis 2013/4 which is available free online. You will see that they plot closest to their nearest neghbours, the French and the Northern Spanish. http://biorxiv.org/search/Lazaridis

Generalissimo
07-19-2014, 03:12 AM
They are thought to be the first settlers of Europe, according to certain theories. Since they are distinct from other Europeans, I wonder what a "pure-blooded" Basque's results would be on an autosomal test such as AncestryDNA that doesn't have a Basque category.

You should update your reading list. It seems to be out of date by about 15 years.

Start here...

http://arxiv.org/abs/1312.6639v2

johnvisintainer24
09-22-2014, 05:05 PM
I have heard Basque are direct descendants of cro magnon is that true?