Genetic diversity in Northern Spain (Basque Country and Cantabria): GM and KM variation related to demographic histories

Abstract

Genetic diversity in Northern Spain (SW Europe)

Human Y-chromosome variation in the Western Mediterranean area: implications for the peopling of the region

“…However, a 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 of this population to a heterogeneous resettlement, including also Moslem slaves [12]. The microsatellite diversity associated with HG25.2 provided coalescence age estimates of ϳ1400 YBP (CI ϭ 540 -2200 YBP).…”

“…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]. In addition, the following samples were analyzed for comparison: 171 from Northeastern Europe (35 from Denmark, 36 from Poland, 74 Estonian, and 26 Russians from Estonia), and 84 from the Middle East (27 Bedouin, 28 Druze, and 29 Palestinians from Israel) ( Table 1).…”

Y Chromosome and Mitochondrial DNA Characterization of Pasiegos, a Human Isolate from Cantabria (Spain)

“…The most probable hypothesis about the origin of Pasiegos, which also holds for other Cantabrians, is that they are the result of an ancient indigenous substrate more or less mixed with more recent immigrants. The other possibility, that the high frequencies found in Cantabrians for lineages with dual geographic origins have been the result of genetic drift, is weakened because it happens in outbred and inbred samples, and it is recurrent in independent male and female genetic lineages as well as in autosomal markers (Esteban et al 1998;Sánchez-Velasco et al 1999).…”

“…Even today, Cantabrians (the Pasiego included, Lebaniegos excluded), at the North of the Iberian Peninsula, seem to be a genetically well differentiated community, as deduced from uniparental and autosomal (Esteban et al 1998;Sánchez-Velasco et al 2003) markers, perhaps to a higher degree than their neighbours, the Basques, who are the best known European isolate on linguistic grounds.…”

“…The region's actual isolation is confirmed by a high degree of endogamy and consanguinity (Tax-Freeman, 1979;Pérez-Flores, 1998;Sánchez-Velasco et al 1999), and a relatively high incidence of some diseases, such as multiple sclerosis, and virtual absence of others such as insulin-dependent diabetes mellitus. Furthermore, genetic studies using GM and KM immunoglobulin markers demonstrated a high degree of genetic differentiation of Pasiegos, that when included with other populations, reveals a considerable range of genetic variation within the Iberian peninsula, higher than that often polarised around the Basque versus non-Basque variation (Esteban et al 1998). Concerning the origin of the Pasiegos at least three theories can be considered: i) Pasiegos are descendants of the primitive inhabitants of Cantabria.…”