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

Abstract

SummaryClassical, mitochondrial DNA (mtDNA) and Y chromosome markers have been used to examine the genetic admixture in present day inhabitants of the Canary Islands. In this study, we report the analysis of ten autosomal Alu insertion polymorphisms in 364 samples from the seven main islands of the Archipelago, and their comparison to continental samples. The detection of population‐specific alleles from the Iberian Peninsula and Northwest Africa, as well as their affinities on the basis of genetic distances and principal component analysis, support a clear link between these populations. Coincident with previous results, the Canarian gene pool can be distinguished as being halfway between those of its putative parents, although with a major Iberian contribution (62‐78%). Both the substantial Northwest African contribution (23‐38%), and the minor sub‐Saharan African input (3%), suggest that the genetic legacy from the aborigines and slaves still persists in the Canary Islanders.

The relationship between microsatellite instability and PTEN gene mutations in endometrial cancer

“…The population of the Canary Island presents a homogeneous Caucasian phenotype, with (i) a major Iberian contribution (up to 80%); (ii) a substantial Northwest African input (up to 40%); and, (iii) a minor sub-Saharan African representation (under 5%). [49][50][51] The patients of our series were also Caucasian. In the healthy population, the 3 mononucleotide loci used to establish the MSI status were quasi monomorphic with infrequent alleles only 1 nucleotide longer or shorter.…”

A CXCL2 tandem repeat promoter polymorphism is associated with susceptibility to severe sepsis in the Spanish population

“…It can thus be argued that our result may be a false positive, albeit continental and island populations are not genetically different, 15 even when compared using highly structured genetic markers of the Y-chromosome. 19 Such a scenario is known to preserve subtle population stratification that can still increase the likelihood of false positives in association tests.…”

“…14,15 The principal factors contributing to differences among Spanish populations relate to the levels of external influences, both from the Near East and North Africa. 16 It is well recognized that, with some exceptions such as the Basques, 17 the Near East influence is homogeneous in the current Spanish population.…”

Alleles with short CAG and GGN repeats in the androgen receptor gene are associated with benign endometrial cancer

“…Unfortunately, information on oral contraceptives (OC) users was not available from our patients and, since a number of them have died, that information cannot be collected at this point. Unpublished data from the ''CDC of the Canary Islands'' cohort study, which has surveyed more than 7,000 subjects 35 , show that the 60% of the general women population of the Canary Islands used OC for at least 1 year, and on the average they used OC for 5 or more years (Cabrera de Leon, personal communication). We estimate that patients of our series have used OC in the same proportion, although the potential bias caused in our study by the lack of a more precise information should be taken into account.…”

“…Studies on the gene pool of the Canary Islands' population have revealed a slightly different composition from one to another island, but, in either case, its ancestries had: (i) a major Iberian contribution (up to 80%); (ii) a substantial Northwest African input (up to 40%); (iii) a minor sub-Saharan African representation (under 5%); and (iv) no oriental contribution. [33][34][35] Since the allele frequencies for both AR polymorphisms may greatly vary depending on the ethnic background of the study subjects, [30][31][32] a large study comprising more than 1,300 subjects is underway to know the precise distribution of the CAG and GGN tracts of the AR gene in the Canary Islands population.…”