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Most recent and deepest study about Canarians using the largest and most diverse Canary Islands sample analyzed to date at a genomic scale : 416 individuals (34 from El Hierro, 35 from La Palma, 78 from La Gomera, 64 from Tenerife, 117 from Gran Canaria, 32 from Fuerteventura, and 56 from Lanzarote)
Genomic Analyses of Human European Diversity at the Southwestern Edge: Isolation, African Influence and Disease Associations in the Canary Islands, Guillen-Guio et al. 2018
Abstract
Despite the genetic resemblance of Canary Islanders to other southern European populations, their geographical isolation and the historical admixture of aborigines (from North Africa) with sub-Saharan Africans and Europeans have shaped a distinctive genetic makeup that likely affects disease susceptibility and health disparities. Based on single nucleotide polymorphism array data and whole genome sequencing (30×), we inferred that the last African admixture took place ∼14 generations ago and estimated that up to 34% of the Canary Islander genome is of recent African descent. The length of regions in homozygosis and the ancestry-related mosaic organization of the Canary Islander genome support the view that isolation has been strongest on the two smallest islands. Furthermore, several genomic regions showed significant and large deviations in African or European ancestry and were significantly enriched in genes involved in prevalent diseases in this community, such as diabetes, asthma, and allergy. The most prominent of these regions were located near LCT and the HLA, two well-known targets of selection, at which 40‒50% of the Canarian genome is of recent African descent according to our estimates. Putative selective signals were also identified in these regions near the SLC6A11-SLC6A1, KCNMB2, and PCDH20-PCDH9 genes. Taken together, our findings provide solid evidence of a significant recent African admixture, population isolation, and adaptation in this part of Europe, with the favoring of African alleles in some chromosome regions. These findings may have medical implications for populations of recent African ancestry"
"For K=4, the overall ancestry proportions among Canary Islanders were, on an average, 22% NAF and 3% SSA (table1)... By using the largest and most diverse Canary Islands sample analyzed to date at a genomic scale, we recognized a wider range of interindividual African ancestry assignments (as much as 29.9% NAF and 9.2% SSA), the largest so far identified in southwestern EUR populations (Botigue et al. 2013)..….. the proportion of SSA ancestry we observed in Canary Islanders likely originated in the postconquest importation of enslaved African people."
Global 25 coordinates : https://drive.google.com/open?id=17u...RqDPkOOFx3LCwt
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