Appendix 2, Part 11: RACIAL MIXING IN IBERIA (SPAIN) The historical record of Spain is clear: although it is majority White, the population has been affected by three factors: the 700 year long occupation by the mixed race Moors, the African slave trade and the 500 year long influx by mixed race Gypsies. Considering the pressures to which Spain has been subjected, the relatively low levels of admixture are a tribute to the resilience of the White Spanish. Caveat: It is important to bear in mind that these results do not imply that all modern Spanish are of mixed origin.
SUB-SAHARAN mtDNA DETECTED IN SPAIN In a study released in the Annals of Human Genetics, Volume 67 Issue 4 Page 312, entitled Joining the Pillars of Hercules: mtDNA Sequences Show Multidirectional Gene Flow in the Western Mediterranean (S. Plaza, et. al.), sub-Saharan L haplogroup sequences are found at frequencies 3% in Iberia. http://www.blackwell-synergy.com/links/doi/10.1046/j.1469-1809.2003.00039.x/abs/ |  Annals of Human Genetics Volume 67 Issue 4 Page 312 - July 2003 | | Joining the Pillars of Hercules: mtDNA Sequences Show Multidirectional Gene Flow in the Western Mediterranean S. Plaza, F. Calafell, A. Helal, N. Bouzerna, G. Lefranc, J. Bertranpetit and D. Comas Genetic Exchange Through the Mediterranean
Each of the subregions analysed (NW Africa and SW Europe) shows sequences that originated on the opposite shore of the Mediterranean. This is particularly clear in the case of U6 and L in SW Europe. L sequences are found at frequencies 3% in Iberia and 2.4% in Italy. Given the relatively high frequencies of L sequences in NW Africa, it is not clear whether they were contributed by the historical populations movements from the south to the north of the Mediterranean (such as the Moslem invasions of the 7th-11th centuries), or whether its presence is associated with other processes not directly linked to NW Africa. Out of 23 different L sequences in Iberia, two were also found in NW Africa (as well as in sub-Saharan Africa), and 7 others were found in sub-Saharan Africa (in a dataset comprising 1,158 individuals from 20 populations; Graven et al. 1995, Pinto et al. 1996; Watson et al. 1996; Mateu et al. 1997; Rando et al. 1998; Krings et al. 1999; Pereira et al. 2001; Brehm et al. 2002) but not in NW Africa. Treating the set of L sequences in Iberia as if it were a population reveals genetic distances from some W African populations, such as the Senegalese and Yoruba, that are slightly smaller than those between L sequences in Iberia and NW Africa. Thus, it may be the case that gene flow from NW Africa is not entirely responsible for the presence of L sequences in Iberia.
As hinted above, the presence of haplogroup U6 in Iberia may signal gene flow from NW Africa, and those of the subhaplogroup U6b1 recent gene flow from the Canary Islands. Haplogroup U6 is present at frequencies ranging from 0 to 7% in the various Iberian populations, with an average of 1.8%. Given that the frequency of U6 in NW Africa is 10%, the mtDNA contribution of NW Africa to Iberia can be estimated at 18%, with a 95% confidence interval of 8%-26% (estimated by sampling with replacement 10,000 times in populations having the same sample sizes and U6 frequencies as Iberia and NW Africa). This is larger than the contribution estimated with Y-chromosomal lineages (7%, 95% confidence interval 1%-14%, Bosch et al. 2001). Full article can be found here. |
| http://www.journals.uchicago.edu/AJHG/journal/issues/v68n4/002582/002582.html |  The American Journal of Human Genetics, 68:1019-1029, 2001 | | High-Resolution Analysis of Human Y-Chromosome Variation Shows a Sharp Discontinuity and Limited Gene Flow between Northwestern Africa and the Iberian Peninsula Elena Bosch, Francesc Calafell, David Comas, Peter J. Oefner, Peter A. Underhill, and Jaume Bertranpetit In the present study we have analyzed 44 Y-chromosome biallelic polymorphisms in population samples from northwestern (NW) Africa and the Iberian Peninsula, which allowed us to place each chromosome unequivocally in a phylogenetic tree based on >150 polymorphisms. The most striking results are that contemporary NW African and Iberian populations were found to have originated from distinctly different patrilineages and that the Strait of Gibraltar seems to have acted as a strong (although not complete) barrier to gene flow. In NW African populations, an Upper Paleolithic colonization that probably had its origin in eastern Africa contributed 75% of the current gene pool. In comparison, 78% of contemporary Iberian Y chromosomes originated in an Upper Paleolithic expansion from western Asia, along the northern rim of the Mediterranean basin. Smaller contributions to these gene pools (constituting 13% of Y chromosomes in NW Africa and 10% of Y chromosomes in Iberia) came from the Middle East during the Neolithic and, during subsequent gene flow, from Sub-Saharan to NW Africa. Finally, bidirectional gene flow across the Strait of Gibraltar has been detected: the genetic contribution of European Y chromosomes to the NW African gene pool is estimated at 4%, and NW African populations may have contributed 7% of Iberian Y chromosomes. The Islamic rule of Spain, which began in A.D. 711 and lasted almost 8 centuries, left only a minor contribution to the current Iberian Y-chromosome pool. The high-resolution analysis of the Y chromosome allows us to separate successive migratory components and to precisely quantify each historical layer. |
MOORISH INFLUENCE IN IBERIA According to the study Human Y-Chromosome variation in the Western Mediterranean area: implications for the peopling of the region. by R Scozzari, et. al., and published in Human Immunology, 62(9):871-874 (2001)., the newly defined haplogroup 25.2 reveals the influence of the Moors in Iberia: http://www.elsevier.com/gej-ng/10/21/30/47/39/28/article.pdf (requires subscription to access) |  Human Immunology, 62(9):871-874 (2001) | Human Y-Chromosome variation in the Western Mediterranean area: implications for the peopling of the region. by R Scozzari, F Cruciani, A Pangracio, P Santolamazza, G Vona, P Moral, V Latini, L Varesi, M Memmi, V Romano, G De Leo, M Gennarelli, J Jaruzellska, R Villems, J Parik, V Macaulay, A Torroni. "Among the Spanish populations, a small sample of 19 subjects from an isolated population living in a restricted area (Pas valleys) of the community of Cantabria is of particular interest. The origin of this population is not clearly defined [11], although some historical information traces the peopling of the region back to the 11th century as a result of a repopulating from different sources, including Moorish slaves [12]. The newly defined HG25.2 originated on a HG25.1 background. In Africa, HG25.2 is observed in 29% Arabs and 71% of Berbers from Morocco, but is not found in those Ethiopian populations in which a high frequency of the ancestral HG25.1 is observed (R.Scozzari and associates, unpublished results [18]). Outside Northern Africa, HG25.2 was seen at generally low frequencies in Spain, France, and Italy, although no traces could be detected in the Near East. However, particularly high frequency of this haplogroup (42%) was found in the Pasiego of the Pas valleys. In the correspondence analysis (Figure 6), the Pasiego do not cluster with the other Spanish populations, but rather with the Arabs and Berbers from Morocco, supporting historic and demographic records that would trace back the origin this population to a heterogeneous resettlement, including also Moslem slaves [12]. The microsatellite diversity associated with HG25.2 provided coalescence age estimates of ;1400 YBP (CI 5 540–2200 YBP). Although it is not possible at present to determine where HG25.2 originated, the simplest interpretation of our data is that HG25.2 diverged from the ancestor HG25.1 somewhere in North Africa a few thousand years ago. A founder effect led first to its expansion among the Berber populations, followed, in historical time, by its spread into the Iberian peninsula. Interestingly, the distribution YAP(1)/DYS271(A) chromosomes was recently demonstrated to be strongly clinal in Portugal, with the highest frequencies in the south, and interpreted as a reflection the Moorish invasions from North Africa in the Middle Ages [45]. A dissection of the Portuguese YAP(1)/ DYS271(A) chromosomes by PN2 and XY275Y would determine whether they indeed belong to HG25.2, could be inferred from an early report, which unfortunately did not provide haplotype information [46]." |
HG25.2, which most likely indicates recent North African admixture, was found at the following frequencies in this study: | Southern Spaniard: 1.6 | | Asturias: 2.2 | | Pasiegos: 42.1 | | Morrocan Arab: 28.6 | | Morrocan Berber: 71 |
Presuming that (1) the mixed race North African Moors had between 28.6% and 71% HG25.2; (2) there was no HG25.2 in Iberia prior to the Moorish invasion; and (3) the average level of HG25.2 across Iberia today is 2%; This would imply that about 3-7% of Iberian male lineages are of Moorish origin, though this is evidently higher in places like the Pas valley.
http://muse.jhu.edu//journals/human_biology/v073/73.5lucotte.html (requires subscription to access) |  Human Biology 73.5 (2001) 763-769 | North African Genes in Iberia Studied by Y-Chromosome DNA Haplotype 5
Gérard Lucotte, Nathalie Gérard, and Géraldine Mer Abstract: The frequency of haplotype 5 at the Y-chromosome-specific DNA polymorphism (p49/TaqI) was reported in a study of 487 males originating from five different geographic locations in Iberia and North Africa. The highest frequency of haplotype 5 (68.9%) was previously observed in Berbers from Morocco, and it has been established that this haplotype is a characteristic Berber haplotype in North Africa. The relative frequencies of haplotype 5 distribution show a geographical gradient of decreasing frequency according to latitude in Iberia: 40.8% in Andalusia, 36.2% in Portugal, 12.1% in Catalonia, and 11.3% in the Basque Country; such a cline of decreasing frequency of haplotype 5 from the south to the north in Iberia clearly establishes a gene flow from North Africa towards Iberia.
Key Words: DYS1,P49/TAQI, Berberian haplotype, Southwest Europe During the 7th century A.D., Muslims coming from the Arabian Peninsula and the Middle East recruited Berbers on their way to invading the north. One of the most important population movements on both sides of the Mediterranean Sea was the conquest of the Iberian Peninsula by North Africans, soon after this first Muslim invasion. More than eight centuries (from the 8th to the 15th century) of Muslim domination in the southern part of Iberia created an important cultural legacy and possible gene exchange between North African and Iberian populations. It has also been documented that genes from the Mediterranean area entered Iberia in more ancient times (Arnaiz-Villena et al. 1999).
Variations in DNA sequences specific to the nonrecombinant part of the Y chromosome are particularly interesting from a general population genetics point of view, because they relate to paternal ancestry. The first published and most informative DNA probe used in Southern blots for this objective is p49 (locus DYS1), which is able to identify some TaqI male-specific fragments: the A, B, C, D, F, and I fragments are polymorphic between individuals (Lucotte and Ngo 1985), and 16 main corresponding haplotypes (numbered 1-16) were identified in the first population study using the p49 probe (Ngo et al. 1986) on DNA samples of unrelated males living in France. Haplotype 15 (A3, C1, D2, F1, I1) was the most widespread haplotype (23%) in this initial study, and elevated frequencies of [End Page 763] haplotype 15 were later observed in French Basques (Lucotte and Hazout 1996). The geographic distribution of haplotype 15 in Europe shows a gradient of decreasing frequency from this Basque focus towards the southwest, but also towards eastern peripheral countries (Lucotte and Hazout 1996; Lucotte and Loirat 1999).
Haplotype 5 (A2, C0, D0, F1, I1) has a particularly high frequency (55%) in North Africa (Lucotte et al. 2000), and is of predominantly Berber origin. Accordingly, in the present study we examined the relative frequencies of haplotype 5 and other haplotypes in four Iberian populations, and compared them to those of a Berber population living in North Africa.
The 487 samples studied (Figure 1), already described for haplotype 15, correspond to unrelated adult males whose origin is based on the birth place of their fathers and (at least) grandfathers. The Berber sample (group E) consisted of 74 Berbers, natives of Morocco and living near Marrakech (Lucotte et al. 2000). The Basque sample (group A) consisted of 97 French Basques, as already described (Lucotte and Hazout 1996). The Catalonia sample (group B) consisted of 76 French Catalans from Perpignan (Lucotte and Loirat 1999), plus 31 Spanish Catalans from Barcelona living in France (Lucotte and David 1992). The Portuguese sample (group C) consisted of 79 Portuguese living in France and originating from the northern part of the country (Lucotte and Loirat 1999), and 59 originating from the southern part of the country (Lucotte and David 1992; Lucotte and Loirat 1999). The Andalusian sample (group D) consisted of 71 Spaniards originating from the region of Seville (Lucotte and Loirat 1999).
DNA was extracted from venous blood, according to a classical method (Gautreau et al. 1983). At least 5 µg of genomic DNA was restricted with TaqI enzyme, [End Page 764] and separated by electrophoresis on a 1.5% agarose gel. The restricted DNAs were transferred then to Hybond N+ membranes by the method of Southern, and hybridized with two probes oligolabeled by random priming; these two probes, used consecutively, were the 2.8 kb p49f-EcoRI insert, and the 0.9 kb p49a-(XbaI and BamHI) insert (method as described in Lucotte et al. 1994). The TaqI fragments (named alphabetically A-Q) are revealed in genomic DNA, most of which are male specific. Among these the A, B, C, D, F, and I bands can be either present or absent between individuals (variants present or zero); fragments A (variants A1A4) and D (variants D1 and D2) can also show variations in size.
The frequencies of the 16 main haplotypes initially found in Europe (Ngo et al. 1986; Lucotte and Hazout 1996) in the five populations studied are given in Table 1. All 16 haplotypes are represented in the five groups considered as a whole; haplotype 15 is the most frequent (36.8%), as it was for the first European populations studied (Ngo et al. 1986). The highest value obtained in our series was for Basques (72.1%), as has been found earlier (Lucotte and Hazout 1996), and the percentages of haplotype distribution show a decreasing gradient from north to south from this Basque focus (summarized in Lucotte and Loirat 1999): 37.4% in Catalonia, 34.8% in Portugal, and 29.6% in Andalusia; haplotype 15 is absent in Berbers from Morocco. Such a cline, starting from the Basque focus and extending to peripheral regions in Europe, has been observed by several authors (Semino et al. 1996; Cavalli-Sforza and Minch 1997; Barbujani et al. 1998; Quintana-Murci et al. 1999; Casalotti et al. 1999). [End Page 765]
In our own present data concerning southwest European frequencies, haplotype 15 frequencies are heterogeneous among the five populations studied (c2 = 97.15; degrees of freedom [df] = 4), a statistically significant value (> 9.49) with p < 0.001; there is a significant (p < 0.01) positive correlation of haplotype 15 frequencies with northern latitude (r = 0.924), with the correlation equation: y = 0.08x - 2.73.
The study of variations in the frequency of haplotype 5, the second most frequent (31.6%) haplotype (Table 1), is the main purpose of the present study. The most elevated value obtained for haplotype 5 in our series was for Berbers (68.9%), and percentages of haplotype distributions show a gradient of decreasing frequency north from Morocco: 40.8% in Andalusia, 36.2% in Portugal, 12.1% in Catalonia, and 11.3% in the Basque region. Haplotype 5 frequencies are heterogeneous among the five populations tested (c2 = 88.97); there is a significant (p < 0.001) negative correlation of haplotype 5 frequencies with latitude (Figure 2).
Haplotype 5, the "Berber haplotype" (Lucotte et al. 2000), therefore allows assessment of the patrilineal North African gene flow into Iberia. For the corresponding matrilineal gene flow, mitochondrial DNA (mtDNA) analyses have already shown that the Iberian Peninsula is differentiated in terms of levels of genetic diversity and presence of unique lineage groups (Córte-Real et al. 1996). In this last study it might be considered that the North African Berber branch had some input into Iberia (quantified as approximately 10% in Spanish mtDNA lineages, 7% in Portuguese, and none in Basque).
Initial studies on genetic markers corresponding to nuclear gene frequencies in human populations in the Iberian Peninsula (Bertranpetit and Cavalli-Sforza 1991; Calafell and Bertranpetit 1993) have shown that the first principal component (PC) of gene frequencies (the percentage of variation explained by this factor being 27.1%) is that between people originally of Basque and non-Basque descent. The second PC (14.5% of variation explained, and 41.6% cumulated) points to the genetic divergence between Catalonia and the central and south central parts of Iberia. The third PC (12.3%, and 53.9% cumulated) concerns the Mediterranean as opposed to the Atlantic regions. The fourth and fifth factors cover a reasonable portion of variance (9.6% and 9.0%, respectively), but they were more difficult to interpret. No factor examined in these studies seems to involve the southern Iberian Peninsula, and the authors concluded that it was unlikely that the North African genetic contribution would be easily detectable by these methods of analysis.
In fact, a more recently published synthesis (Arnaiz-Villena et al. 1999), based on genetic markers in Basques, Portuguese, Spaniards, and North Africans, supports substantial gene flow from paleo-North African populations to Iberia. Some genetic studies, in particular on the HLA system (Arnaiz-Villena et al. 1995; Martínez-Laso et al. 1995; Arnaiz-Villena et al. 1997), have shown Iberian populations to be more closely related to North African populations than to the rest of Europe. In a recent study (Gómez-Casado et al. 2000), Moroccan Algerians show the closest genetic distance--based on HLA class I (A and B) and class II (DRB1) markers--followed by Berbers, Spaniards, and Basques. North African input into Iberia may be close to 20%, as shown by nuclear CD4/Alu markers (Flores et al. 2000b). It seems that the significance of the genetic links detected between North Africa and Iberia reflect both an ancient common substratum (Arnaiz-Villena et al. 1999) and, to a lesser degree, possible contacts between Christians and North African Muslims (A.D. 710-1492) in Iberia (Kandil et al. 1999), who had a Berber genetic substratum.
Recent data on Y-chromosome haplotypes (Flores et al. 2000a) show that Iberian Peninsula DNA samples provide evidence of some North African gene flow, as reflected by their having a comparatively higher frequency of DYS19A (this allele having also its highest representation in North Africa). As for haplotype 5, a west-east gradient emerges for the frequency of DYS19A in North Africa. Because of the strong linkage disequilibrium between the two alleles in the DYS19A/YAP haplotype, this gradient could also exist for this later allele.
Acknowledgments We acknowledge in particular S. Berriche, P. Guérin, and F. David for DNA extraction and hybridization experiments. The present research is included as our contribution to the Genetic Diversity Program that has been established for European populations. We thank Professor Arnaiz-Villena, Madrid University (Spain) for helpful comments in the successive versions of our manuscript. |
GYPSY INFLUENCE A mistake which many observers make when visiting Spain is to presume that the large number of Gypsies to be found there (estimates are that there are now over one million in Spain alone) are Spanish. They are not, and this can contribute to a mistaken impression of nature of the population. The Gypsies are an originally Indian, but now quite mixed, population which has spread all over Europe, as evidence by this distribution map, dating from the year 2000: 
Below: Typical Gypsies in Spain: |  | Below: Typical Gypsies in Romania: |  |
Chapter 22 Main Contents Page All material (c) copyright Ostara Publications, 1999. Re-use for commercial purposes strictly forbidden. |