Phylogeographic patterns of mtDNA reflecting the colonization of the Canary Islands

Abstract

Although the Canary Islands were settled by humans, possibly of Berber origin, as late as 2500 years ago, the precise course and numbers of early migrations to the archipelago remain controversial. We have therefore analysed mtDNA variation (HVS‐I as well as selected RFLP sites) in 300 individuals from the seven Canary Islands. The distribution and variation across the islands in a specific mtDNA clade of Northwest African ancestry suggest that there was one dominant initial settlement process that affected all the islands, from east to west. This indicates that a certain genetic affinity of present‐day Canary Islanders to Northwest African Berbers mainly stems from the autochthonous population rather than slaves captured on the neighbouring African coast. The slave trade after the European conquest left measurable, though minor, traces in the mtDNA pool of the Canary Islands, which in its majority testifies to the European immigration.

A Tale of Aborigines, Conquerors and Slaves: Alu Insertion Polymorphisms and the Peopling of Canary Islands

“…An exceptional case was El Hierro, for which the genetic distances, although non-significant, point to a closer affinity with Northwest Africans than Iberians. This distinctiveness could be due to a higher sub-Saharan African influence in this Island, as has been observed for mtDNA (Rando et al 1999, Flores et al 2001a) and the Y chromosome (Flores et al 2003). However, it should be noted that the distance between Canarians and Northwest Africans were two times smaller than those between Iberians and Northwest Africans (Table 2).…”

“…Particularly, in the case of the Canary Islands, both have provided a more reliable vision of the genetic composition of the present day population. From mtDNA data, besides the sub-Saharan African influence, a more important Northwest African one was detected (Pinto et al 1996;Rando et al 1999). Furthermore, ancient mtDNA has demonstrated that this Northwest African influence is not only due to slavery but mostly due to aborigine heritage (Maca-Meyer et al 2004).…”

The maternal aborigine colonization of La Palma (Canary Islands)

“…Genetic studies on diversity and frequency distribution of polymorphic markers in the current populations of the seven islands have also given inconclusive results. The correlation patterns found for mtDNA, CD4/Alu haplotypes, and AB0 allele frequencies were congruent with only one dominant settlement process, 2,3,10 whereas the distribution and dating of some Y-chromosome North African lineages, present in the Canary Islands, matched with a pattern of settlement of the archipelago in two stages. 4 If the aboriginal colonizers reached the islands by themselves, using primitive boating skills, they most probably landed first on the nearest eastern islands from the mainland and, under demographic pressure, ventured afterwards to the next western island at sight.…”

“…This apparent discrepancy was due to the fact that exact L haplotypic matches between North Africa and the historical sample from Tenerife 5 were greater than between the former and Gran Canaria. 2 …”

“…Internal DNA extraction For internal extraction, teeth were again thoroughly washed, this time, with 15% HCl, rinsed with UV-treated ddH 2 O, and then exposed to UV light for 10 min. To reconstruct the tooth after extraction, it was cut through the midline using a dentist electric saw and the internal pulp and dentin drilled out using a dental drill.…”