viernes, 23 de diciembre de 2011

North-African marker E-M81 in Europe

Here is a list obtained from different studies, for the typical North-African y-dna subclade E-M81 (part of the marco haplogroup E) , for populations of Europe (outside of Iberia) :

West-Flanders : 1/110 = 0.9%   Larmuseau et al. 2013
Vlaams-Waals Brabant :  1/124 =  0.8%  Larmuseau et al. 2013
Belgium Total (all the study) :  2/773 = 0.3%  Larmuseau et al. 2013

Germany   n= 1/345    0.29%    Rebala et al. 2012

Haskovo, Bulgaria n = 1/41  2.4%  Karachanak 2013.
Total Bulgaria    n = 1/808  0.12%   Karachanak 2013.

Greeks               n = 3/92    3.3%   Battaglia et al. 2008
Macedonian-Greeks  n=1/57   1.8%   Battaglia et al. 2008

Croats               n = 1/89   1.1%   Battaglia et al. 2008

North-Italians      n=1/67  1.5%   Cruciani 2004.
Lombard             n=1/18  5.6%   Scozzari 2001.
Venetian              n=20     0.0%   Scozzari 2001.
Ligurian               n=17     0.0%   Scozzari 2001.
Bologna               n =29    3.4%  Boattini et al. 2013           

Central Italians    n=2/89     2.2%   Cruciani 2004.
Latium                n=1/66     1.5%   Scozzari 2001.
Toscana             n=123       0.8%    Boattini et al. 2013

South Italy/Sicily
Southern Italians   n=0/87    0.0%   Cruciani 2004.
Sicilians                 n=1/136   0.7%   Cruciani 2004.
Sicily                    n= 141     2.8%   Boattini et al. 2013
Cosenza              n=1/45      2.22%

Sardinians             n=1/367   0.3%   Cruciani 2004.
Sardinia                n=82        1.2%   Boattini et al. 2013

French               n=3/85    3.5%   Cruciani 2004.
French              n=3/73  4.1%   Scozzari 2001.
Auvergne           n=5/89  5.62   Cruciani 2004.
Île-de-France     (5/91)   5.49   Cruciani 2004.
Gascony             n=0/24  0.0%    Adams et al.
Béarn, Gascony   n=1/56  1.78%  Martínez-Cruz et al. 2012,
Bigorre, Gacony  n=1/44  2.72%  Martínez-Cruz et al. 2012
Provence-Alpes-Côte d'Azur n=1/45 2.22% Ramos-Luis et al. 2013.
Nord-Pas-de-Calais n=3/70 4.29% Ramos-Luis et al. 2013
Midi-Pyrénées n=1/67 1.49% Ramos-Luis et al. 2013.

viernes, 25 de noviembre de 2011

North-African marker in Andalusia

We find the following percentages for the typcial north-african (Berber) paternal marker, the Y-DNA haplogroup E-M81, obtained from different sources :

Southern Spaniards  n=1/62    1.6%    Scozzari 2001.
Huelva, Andalusia   n=5/167   2.99%  Ambrosio 2010.
Huelva, Andalusia   n=1/22      4.5%   Flores et al.2004
Seville, Andalusia  n=7/155     4.5%    Flores et al.2004
Cadiz, Andalusia    n=0/28      0.0%    Flores et al.2004
Cordoba, Andalusia  n=2/27   7.4%    Flores et al.2004
Malaga, Andalusia   n=3/26    11.5%   Flores et al.2004
Andalusia East      n=2/95       2.1%    Adams et al.
Andalusia West      n=10/73   13.7%   Adams et al.
Total South Spain :  31/655 = 4.73%

It is a similar result to percentages found in  French  (3/73 = 4.1% , Scozzari et al. 2001) or in regions of France ( 5.6% in Auvergne (5/89) and Île-de-France 5/91 = 5.5% ). This suggests that the presence of Islamic rule, which was longer in the South of Spain than anywhere else in Iberia, had very limited or no impact in the genetic pool of the population. We can conclude that the moorish population in Andalusia was extremely minoritary, the place were Islamic rule was stronger and longer. We can't also rule out the possibily that the presence of this marker, or part of it, could have entered in much earlier times (Neolithic or earlier), which would make the presence of moors in Al-Andalus even more insignificant. So, in other words, we can safely say the Islamic rule was just that, a military and religious rule, with no impact on the demographics and genetics of the authoctonous populations.

Ambrosio et al. 

The distribution of E-M81 haplogroup, a Berber marker, was found at a frequency of 3% in our sample. The distribution of M81 frequencies in Iberia seems to be not concordant with the regions where Islamic rule was most intense and long-lasting. The study also showed that most of M78 derived allele (6.6%) led to the V13* subhaplogroup. We also found the most basal and rare paragroup M78* and others with V12 and V65 mutations. The lineage defined by M34 mutation, which is quite frequent in Jews, was detected as well. Conclusions: The haplogroup E among Western Andalusians revealed a complex admixture of genetic markers from the Mediterranean space, with interesting signatures of populations from the Middle East and the Balkan Peninsula and a surprisingly low influence by Berber populations compared to other areas of the Iberian Peninsula.

lunes, 7 de noviembre de 2011

Sub-Saharan admixture in the Mediterranean basin

González-Pérez et al. (2010) have analyzed populations from the northern and southern shores of the Mediterranean, with Central Europeans and West Africans as external references. In the Discussion section, they admit that the inflated "Alu/STR estimate might be artefactual" and favor the estimate based on the Alu  loci set alone because it's consistent with previous mtDNA, Y-chromosome and 500,000-SNP structure data.
According to the more accurate latter method, Sub-Saharan African admixture is ~13% in North Africa and "imperceptible" or noise (~ 0.01%) in Southern Europe:

miércoles, 2 de noviembre de 2011

Pyrenean Y-DNA

In the pie charts, dark blue refers
to R1b1b2d, dark light to R1b1b2c, white to other R, orange
to I2a2, salmon to other I and pink to lineages that entered
Iberia from the Neolithic onwards. The light gray slice refers to
R plus I lineages.
From the study of  López-Parra et al. 2009 which analyses 5 pyrenean populations (25 males from Vall d'Arán (Lleida province), 34 from Alt Urgell (Lleida province), 37 from Cerdanya (Girona province), 31 from Jacetania (Huesca province) and 42 from Cinco Villas (Navarre province).

As expected, the vast majority by far of these populations belong to haplogroup R1b1b2-M269 (total 131/169 = 77.5%), especially the subhaplogroup R1b1b2*, and the second most common haplogroup among the total Pyrenean samples was haplogroup I which accounted for 12.4% (21/169) of paternal lineages, being I2a2 the most common clade. The rest of haplogroups are quite minoritary. Here are the distributions for each of the pyrenean populations sampled :

Cerdeña (n=37)
R1b: 75.7%  I: 16.2%  G : 2.7%  J: 2.7%  E: 0% 

Alt Urgell (n=34)
R1b: 76.5%  I: 8.8%  J: 8.8%  E: 2.9% 

Vall d'Arán (n=25)
R1b : 84%  I: 12%  E: 4%  J: 0%

Jacetania (N=31) :
R1b : 64.%  I: 16.1%   J: 9.7%  R1: 6.45%    G: 3.2%   E: 0%

Cinco Villas (n=42)
R1b: 85.7%  I:  14.3%

TOTAL (n=169) :  R1b (131/169) : 77.5%  I (21/169) : 12.4%  J (7/169) = 4.14%, G (3/169) = 1.78% E (3/169) = 1.78%,    R1 (2/169) = 1.18%  and  Other 2/169 = 1.18%.


The male-mediated genetic legacy of the Pyrenean population was assessed through the analysis of 12 Y-STR and 27 Y-SNP loci in a sample of 169 males from 5 main geographical areas in the Spanish Pyrenees: Cinco Villas (Western Pyrenees), Jacetania and Valle de Arán (Central Pyrenees) and Alto Urgel and Cerdaña (Eastern Pyrenees). In the Iberian context, the Pyrenean samples present some specificities, being characterizeded by a high proportion of chromosomes R1b1b2-M269 (including the usually uncommon R1b1b2d-SRY2627 and R1b1b2c-M153 types) or I2a2-M26 and low proportions of other haplogroups. Our results indicate that an old pre-Neolithic substrate is preponderant in populations of the whole Pyrenean fringe. However, AMOVA revealed a high level of substructure within Pyrenean populations, partially explained by drift effects as well as by the signature of an ancient genetic differentiation between Western and Eastern Pyrenees.

Other interesting extracts from the study : 

I2a2 is virtually absent east of the Italian Apennines and shows the highest incidences in north-eastern Iberia/southern France, with the exception of the isolated and dramatic peak of frequency (40.9%) in Sardinia (Rootsi et al. 2004).
This was well illustrated in the phylogram of I2a2 in Figure 1 from Rootsi et al. (2004) based upon the population data available at the moment, within which Basques (Spanish and French mixed) and Bearnais (in the French Atlantic Pyrenees) showed the highest continental frequencies (6% and 7.7% respectively). New data from Spanish Basques (Alonso et al. 2005) did not reproduce such elevated values; in Biscay I2a2 was not detected and its frequency was 1.3% in Gipuzkoa and 4.5% in Alava plus Navarra. From the new data presented here it seems that the Pyrenees might indeed have been the region where I2a2 arose and from which it initiated the spreading process after the LGM.

One of the signs comes from the concentration of high frequencies of I2a2 among populations from the entire Pyrenean range. Our data strongly reinforce previous evidence that I2a2 arose during Mesolithic times in a region close to or within the Pyrenees. The dispersal of I2a2 from its place of origin throughout the Pyrenees and beyond, implied not only gene exchange but also considerable movement of people. Very likely, the demographic event associated with the expansion of I2a2 was the Ice-age repopulation of
Europe from the Franco-Cantabrian refuge. A number of studies on human mtDNA diversity have already indicated that the Franco-Cantabrian glacial refuge was a major source for the European gene pool (Achilli et al. 2004), and our data on I2a2 seemingly lend support to the role of the region as a Mesolithic diffusion center of male lineages.

lunes, 31 de octubre de 2011

Celtiberia population estimate

From the book  ENTRE Celtas e Íberos. Las poblaciones protohistóricas de las Galias e Hispania/ editado por Luis Berrocal-Rangel y Philippe Gardes. — Madrid : Real Academia de la Historia : Casa de Velázquez, 2001. — 248 p. : il. ; 30 cm. —(Bibliotheca Archaeologica Hispana ; 8).

Note, the Celtiberia here refers only to the proper Celtiberian tribes, and not all the Celts of Iberia.


The demographic analysis of the Celtiberian is a hard question. To solve it we have analysed the ethnoarchaeological data and we have contrasted it with archaeological data, as the surface of the known Celtiberian civitates and oppida. We have contrasted the results with the few informations transmitted by classical historians and geographers, as the numbers of warriors in Celtiberian armies and the extension of the populi and civitates of Celtiberia after Plinius and Ptolomeus. As conclusion of the analysis, we can consider that Celtiberia, extended about 45.000 km2 had a theoretical demographic density of about 5/6 h./km2 in mountain areas, but could reach 8/10 h./km2 in the best areas, as river valleys and peripheral plains. These results allow us a calculation of the total Celtiberian population between 250.000 h. and about 350.000/450.000 h., a bigger and more logical number. The first demographic anlysis of the Celtiberia offers a interesanting information and very useful for further studies on Archaeology and Ancient History and Geography, and also to better understand the territorial and urban planning, the demography and the sociology of the Celtiberians.

ADMIXTURE up to K=20 (Rasmussen et al. 2011)

The recently published paper by Rasmussen et al. is focused on the Aboriginal Australians, and inlcudes a massive ADMIXTURE analysis up to 20 ancestral components (K=20). The Spaniard sample (taken from Behar et al.) in this run is similar-looking to other Western-European populations, showing the dark-blue component (peaks in Lithuanians) at similar levels as the French, and the whiteish-blue component (peaks in Sardinians).

The original size can be found in the supplementary PDF here (page 159) :

martes, 16 de agosto de 2011

Sub-Saharan haplogroup mtDNA L in Spain and Europe

In the study of Rhouda et al. (2006) in a sample of 686 spaniards, not a single individual with haplogroup mtDNA L was found. In the rest of Western Europe, the recent study of García et al. 2011 finds L up to Northern Germany and Denmark . We observe the following percentages  :

Hérault (Languedoc) 2.4 %
Rhône (Lyonnais) 4.4 %
Vendée and Vienne (Poitou) 0.8 %
Calvados and Seine-Maritime (Normandy) 1.8 %
Somme (Picardie) 1.3 %
France Miscellanea 0.6 %
Scotland 0.1 %
England 0.7 %
Great Britain 0.9 %
North-Germany and Denmark 0.7 %

miércoles, 3 de agosto de 2011

Skin reflectance of selected world populations

From the study of Nina Jablonski and George Chaplin (Academy of Sciences of California).
We can see that Spaniards, from León (NW Spain) and Basques (N Spain), are as light or even lighter than other Western Europeans. Higher values indicate lighter skintone.

Country and population or area

Observed reflectance at 685 nm

Germany (Mainz)
United Kingdom (Northern)
Spain (Basques) 65•70
United Kingdom (Wales) 65•00
Ireland (Rossmore)
Spain (Leon)
United Kingdom (London) 62•30
Iraq/Syria (Kurds) 61•12
Saudi Arabia 52•50
Algeria (Aures) 58•05
Libya (Tripoli)
Libya (Fezzan) 44•00
India (Northern) 53•26
Pakistan 52•30
India (Southern) 46•70
China (Southern) 59•17
Vietnam 55•90
Japan (Northern) 54•90
Philippines (Manila) 54•10
Cambodia 54•00
Japan (Southwest) 53•55
Nepal (Eastern) 50•42
Papua New Guinea 35•30
Australia (Darwin) 19•30
Greenland (Southern) 55•70
Peru (Nunoa) 47•70
Peru (Maranon) 43•05
South Africa (Hottentot) 46•80
Botswana (San) 42•40
Zaire 33•20
Kenya 32•40
Ethiopia 31•70
Tanzania (Sandewe) 28•90
Namibia 25•55
Cameroon (Fali) 21•50
Mozambique (Chopi) 19•45

Source : "The Evolution of Human Skin Coloration". J Hum Evol, 2000; pp. 74-75

lunes, 18 de julio de 2011

R1b frequencies in Spain and Europe

The paper from Belareseque et al. 2010 gives us new percentages of R1b1b2 from different countries of Europe, as we can see in the table below. There is also a map of frequencies. As we can see again, Spain has among the highest percentages of Europe, especially the Spanish Basques, with 87.1 %, second most in Europe after Wales with 92.3 %.

Here are the levels for the regions of Spain :
  • Spain Basques........................87.1 %
  • Catalonia, Spain .....................81.3 %
  • Andalucia East, Spain ............72.0 %
  • Castilla La Mancha, Spain..... 72.0 %
  • Galicia, Spain.........................58.0 %
  • Andalucia West, Spain...........55.0 %

 Complete table with all countries :

Map of frequencies : 

domingo, 17 de julio de 2011

Spaniards genetically similar to Western and Northern Europeans

Study from Gayán et al. 2010 , some extracts :
In this study we have sampled over 800 unrelated individuals from the population of Spain, and have genotyped them with a genome-wide coverage. We have carried out linkage disequilibrium, haplotype, population structure and copy-number variation (CNV) analyses, and have compared these estimates of the Spanish population with existing data from similar efforts. Conclusions: In general, the Spanish population is similar to the Western and Northern Europeans but has a more diverse haplotypic structure. These results suggest that the general Spanish population, as characterized in the present study by sampling from eight different cities widely-spaced across Spain, is generally similar to other European populations, although more genetically diverse than Western and Northern Europeans. Moreover, the Spanish population is remarkably homogeneous within itself in terms of global genetic structure. In view of these results, the population of Spain is sufficiently genetically similar to the CEU sample (White-Americans from Utah) so that the CEU HapMap dataset could be used to infer genotypes for the Spanish population.

North-African mtDNA in Spain...and Europe

The minor presence of the typical north-african mtDNA haplgroup U6  in Spain, even if at low levels, was tought to be higher than anywherelse in Europe. Interestingly we will see that this is not the case. The truth is that U6 is found everywhere in Europe, but it has been found at higher frequencies in France. Obviously these studies make sure the testees are natives, having the 4 grandparents from the same area, and their surnames native. We see now the studies :

In this study of Dubut et al. 2004 there is a total of 4.5% of U6 in Finistère (Brittany, France) and 1.4% in Périgord-Limousin.

In this very recent study of García et al. 2011 we find these frequencies for France :

  • U6a1/a2/a3 Perigord-Limousin (Limousin) 1.4 %
                       Finistère (Brittany) 0.7 %
  • U6a  France Miscellanea 0.6 %
Spain : 

Andalusians n=3/158    1.9%   Plaza 2003.

Asturias   n=1/89     1.1%    Garcia 2011.

Aragón     n=0/119    0.0%    Garcia 2011.

Catalonia-Aragón  n=2/164  1.2%  Garcia 2011.
Catalonia n=3/80    3.9%      Garcia 2011.
Catalonia n=78     0.0 %    Plaza 2003.

Central Spain   n=1/50  2.0%   Plaza 2003.

Basques    n=45  ??   0.6%    Maca-Meyer 2003.
Basques    n=0/377    0.0%    Garcia 2011.
Basques    n=1/85     1.2%    Garcia 2011.
Basques    n=173      0.0%    Plaza 2003.

Galicia      ??       2.3%    Maca-Meyer 2003.
Galicia    n=3/185    1.5%    Garcia 2011.
Galicia    n=2/103      1.9%    Plaza 2003.

Cantabria  n=1/105    1.0%    García 2011.
Potes      n=0/72     0.0%    Maca-Meyer 2003.

Lebaniegos n=0/72   0.0%      Maca-Meyer 2003.
Pasiegos   n=0/82   0.0%      Maca-Meyer 2003.

Valencia   n=0/30     0.0 %     Plaza 2003.

% M1 and U6a1a = 2/214 = 0.93%   Álvarez 2010

TOtal SPain = 18/2.022 = 0.89%

sábado, 16 de julio de 2011

Genetic continuity since pre-Roman times

In this study of Sampietro et al. 2005 have retrieved mitochondrial DNA (mtDNA) from a few of the scarce skeletal remains that have been preserved. 
Phylogeographic analyses show that the haplogroup composition of the ancient Iberians was very similar to that found in modern Iberian Peninsula populations, suggesting a long-term genetic continuity since pre-Roman times.

Here is the whole summary :

The Iberians developed a surprisingly sophisticated culture in the Mediterranean coast of the Iberian Peninsula from the 6th century BC until their conquest by the Romans in the 2nd century BC. They spoke and wrote a non-Indo-European language that still cannot be understood; their origins and relationships with other non-Indo-European peoples, like the Etruscans, are unclear, since their funerary practices were based on the cremation of bodies, and therefore anthropology has been unable to approach the study of this people. We have retrieved mitochondrial DNA (mtDNA) from a few of the scarce skeletal remains that have been preserved, some of them belonging to ritualistically executed individuals. The most stringent authentication criteria proposed for ancient DNA, such as independent replication, amino-acid analysis, quantitation of template molecules, multiple extractions and cloning of PCR products, have been followed to obtain reliable sequences from the mtDNA hypervariable region 1 (HVR1), as well as some haplogroup diagnostic SNPs. Phylogeographic analyses show that the haplogroup composition of the ancient Iberians was very similar to that found in modern Iberian Peninsula populations, suggesting a long-term genetic continuity since pre-Roman times. Nonetheless, there is less genetic diversity in the ancient Iberians than is found among modern populations, a fact that could reflect the small population size at the origin of the population sampled, and the heterogenic tribal structure of the Iberian society. Moreover, the Iberians were not especially closely related to the Etruscans, which points to considerable genetic heterogeneity in Pre-RomanWestern Europe.

Bioanthropology of the Ebro Valley

This is a study from José Luis Nieto Amada called "La biolantropologia del Valle del Ebro" (bioanthropology of the Valley of Ebro) from 1983. The studied populations are the valley of Ebro, that is, from the provinces of Navarra, Rioja, Huesca, Zaragoza, Teruel and part of Lleida. That is, in the Northeast area of Spain.

Here are some quotes from the study :

"In the lands of Ebro, there is a predominance of dark chestnut hair color".

"According to Sánchez Fernández, Zaragoza would be the province with the highest percentage of blondism, with more than 30%. The percentages of Huesca and La Rioja would also be among the highest "

"Our statistics are far from these frequencies, and we place in the Ribera Zaragozona and Navarra (20.5%) the highest concentration of blondism. " 

"In our study, the highest frequencies of blue eyes appear in the communities with also the highes percentage of azure iris. The distribution is very homogeneus between navarrese and aragonese, with a marked difference in the Ribera (21%) and the middle basin of Jiloca. Wheras in Rioja, the percentage is much lower."

Y-chrosome haplogroup R1b in Spain

Paternal Y-chromosome haplogroup R1b subclades frequency in Europe from the study of Myres et al. 2010. As we can see, the highest frequencies in Iberia are M269, M412 (all), L11 (all), S116 (all), and S116*.