The Y-chromosomal Heritage of the Azores Islands Population P. R. Pacheco1,2, C. C. Branco1,2, R. Cabral1,2, S. Costa1,2, A. L. Araujo´ 3 , B. R. Peixoto1,2, P. Mendonc¸a3 and L. Mota-Vieira1,2∗ 1Molecular Genetics and Pathology Unit, Hospital of Divino Esp´ırito Santo, Ponta Delgada, Sao Miguel Island, Azores, Portugal ˜ 2 Instituto Gulbenkian de Ciencia, Oeiras, Portugal ˆ 3Hematology Department, Hospital of Divino Esp´ırito Santo, Ponta Delgada, Sao Miguel Island, Azores, Portugal
Summary The Azores, a Portuguese archipelago located in the north Atlantic Ocean,
had no native population when the Portuguese first arrived in the 15th century. The islands were populated mainly by the Portuguese, but Jews, Moorish prisoners, African slaves, Flemish, French and Spaniards also contributed to the initial settlement. To understand the paternal origins and diversity of the extant Azorean population, we typed genomic DNA samples from 172 individuals using a combination of 10 Y-biallelic markers (YAP, SRY-1532, SRY-2627, 92R7, M9, sY81, Tat, SRY-8299, 12f2 and LLY22g) and the following Y-chromosomal STR systems: DYS389I, DYS389II, DYS390, DYS391, DYS392, DYS393 and DYS385.
We identified nine different haplogroups, most of which are frequent in Europe.
Haplogroup J∗ is the second most frequent in the Azores (13.4%), but it is modestly represented in mainland Portugal (6.8%). The other
non-European haplogroups, N3 and E3a, which are prevalent in Asia and sub-Saharan Africa, respectively, have been found in the Azores (0.6% and 1.2%, respectively) but not in mainland Portugal. Microsatellite data indicate that the mean gene diversity (D) value for all the loci analysed in our sample set is 0.590, while haplotype diversity is 0.9994. Taken together, our analysis suggests that the current paternal pool of the Azorean population is, to a great extent, of Portuguese descent with significant contributions from people with other genetic backgrounds.
Prevalent Y-chromosome Lineages in Azores Islands The non-random distribution of distinctive stable HGs provides patterns of genetic affinity and clues concerning past human movements. Here we investigated the genetic background of the male Azorean population, and discussed the results in light of existing historical records. HG J∗ , defined by the 12f2 deletion, is largely confined to Caucasoid populations, with its highest frequencies being found in Middle Eastern populations. It is thought to have originated in the Middle East, where it accounts for over one third of the Y-chromosomes of Jewish, Turkish and Arab populations (Bosh et al. 2001; Nebel et al. 2001). Our data show that in the Azores this haplogroup is the second most common, with a frequency of 13.4%, twice as high as in mainland Portugal (6.8%; Rosser et al. 2000). Using a sampling strategy based on the three geographical groups of the Azores.
islands, Montiel and colleagues (in this issue) found lineage J at a lower frequency (8.6%) for the whole archipelago, although their study revealed a similar frequency (14.5%) for the islands of the Central group. The high frequency of lineage J raises the question of whether early Jewish settlers left a significant imprint in the genetic pool of the Azorean male population. The overall northwest (NW) African contribution to the Iberian Y-chromosome pool has been calculated as 7%, with the highest level of contribution (14%) being found in Andalusians from southern Iberia (Bosch et al. 2001), a result that is consistent with the population movement associated with Islamic rule in Iberia (Pereira et al. 2000). The frequency of the NW African lineage E∗ (xE3) in mainland Portugal and the Azores (11.7% and 10.5%, respectively) is similar. Montiel and colleagues (in this issue) also found comparable values (13.0%) for the archipelago. The results obtained by us and Montiel at al. suggest several hypotheses for the presence of this lineage in the present-day population of the Azores: a direct input of Moorish prisoners, the influence of early Portuguese settlers, or a contribution of both Moorish prisoners and Portuguese. Lineage E3a, defined by mutation sY81, shows a subSaharan distribution pattern. This HG is the most frequent in west African populations, and its presence can be interpreted as resulting from sub-Saharan gene flow. The occurrence of lineage E3a in the Azores is the result of African influence, since it has been detected neither in Europe, nor in Iberian samples (Semino et al. 2000; Bosch et al. 2001; Rosser et al. 2000). The presence of sub-Saharan African slaves in the archipelago since the beginning of its settlement is well documented (Matos 1989). Therefore, we conclude that the 1.2% Ychromosomes with the E3a background represent the male descendants of black slaves from Guinea, Cabo Verde and Sao Tom ˜ e.´ Lineage N3, defined by a Tat biallelic polymorphism, is specific to Asians and northern Europeans, and has not been found in the Iberian peninsula or in other European countries (Rosser et al. 2000; Helgason et al. 2000). This mutation probably arose in the Mongolia/China area, and its present distribution stretches from Japan to Norway (Zerjal et al. 1997). The presence of this lineage in the Azores (0.6%) is intriguing. Historical records of the presence of Asians or Mongolians in the archipelago are not known, but
Bruges-Armas and colleagues (1999) have recently described the presence of Mongolian HLA genes at a high frequency in the Terceira Island population (Azores). Thus, it is possible that the N3 Lineage may have been introduced during the expansion of trade navigation between Europe, America and Asia, in the XVI and XVII centuries, when the Azores had a strategic role due to its geographic position (Russel-Wood, 1998). Lineage R1b8, defined by a C→T base substitution at the SRY-2627, arose recently in Iberia. This lineage has its highest frequency in Basques (11%) and Catalans (22%), but in other regions these chromosomes are rare or absent (Hurles et al. 1999). In the Azores, its frequency is marginal (0.6%), probably reflecting the descendants of Spaniards who came to the islands during the reign of Spain over Portugal, from 1580 to 1640 (Matos, 1989). Lineage R1a is most frequent in central eastern Europe, comprising approximately half of the chromosomes in Russian, Polish and Slovakian samples. In contrast, frequencies in southeast and southwest Europe are low. In our sample set, R1a is four times more common than in mainland Portugal (Rosser et al. 2000), which may be explained by the following reasons: (i) this chromosome only arrived with Portuguese settlers, and subsequently increased in frequency; (ii) some chromosomes came with Portuguese settlers, while others came directly from central eastern Europeans; and (iii) they are an exclusive contribution from central eastern Europe. Records and papers exploring historical settlement show that some Europeans (e.g. Flemish) contributed to the peopling of the Azores, so we believe that all of the above hypotheses are possible.
Fonte:
https://www.academia.edu/18134784/The_Y_chromosomal_Heritage_of_the_Azores_Islands_Population?email_work_card=view-paperPor isso é que eu gosto da música dos Sardaukar!
