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dp
08-21-2014, 07:02 PM
2409

I was surprised by the large amount of European admixture found throughout the island --looks like its the majority source for the 1000+ subjects, independent of location.
dp :-)

details below:

PLoS Genet 10(7): e1004488. doi:10.1371/journal.pgen.1004488

Cuba: Exploring the History of Admixture and the Genetic Basis of Pigmentation Using Autosomal and Uniparental Markers

Beatriz Marcheco-Teruel et al.

We carried out an admixture analysis of a sample comprising 1,019 individuals from all the provinces of Cuba. We used a panel of 128 autosomal Ancestry Informative Markers (AIMs) to estimate the admixture proportions. We also characterized a number of haplogroup diagnostic markers in the mtDNA and Y-chromosome in order to evaluate admixture using uniparental markers. Finally, we analyzed the association of 16 single nucleotide polymorphisms (SNPs) with quantitative estimates of skin pigmentation. In the total sample, the average European, African and Native American contributions as estimated from autosomal AIMs were 72%, 20% and 8%, respectively. The Eastern provinces of Cuba showed relatively higher African and Native American contributions than the Western provinces. In particular, the highest proportion of African ancestry was observed in the provinces of Guantánamo (40%) and Santiago de Cuba (39%), and the highest proportion of Native American ancestry in Granma (15%), Holguín (12%) and Las Tunas (12%). We found evidence of substantial population stratification in the current Cuban population, emphasizing the need to control for the effects of population stratification in association studies including individuals from Cuba. The results of the analyses of uniparental markers were concordant with those observed in the autosomes. These geographic patterns in admixture proportions are fully consistent with historical and archaeological information. Additionally, we identified a sex-biased pattern in the process of gene flow, with a substantially higher European contribution from the paternal side, and higher Native American and African contributions from the maternal side. This sex-biased contribution was particularly evident for Native American ancestry. Finally, we observed that SNPs located in the genes SLC24A5 and SLC45A2 are strongly associated with melanin levels in the sample.


I did some looking at Dienekes Blog, where I came across the above, and found in a different area a cross post from 23andme. Here's an excerpt that may be relevant:
"On average Latinos had about 70 percent European ancestry, 14 percent Native American ancestry and 6 percent African ancestry."
They explain that the missing 10% is of uncertain admixture.

R.Rocca
08-21-2014, 07:58 PM
2409

I was surprised by the large amount of European admixture found throughout the island --looks like its the majority source for the 1000+ subjects, independent of location.
dp :-)

details below:

PLoS Genet 10(7): e1004488. doi:10.1371/journal.pgen.1004488

Cuba: Exploring the History of Admixture and the Genetic Basis of Pigmentation Using Autosomal and Uniparental Markers

Beatriz Marcheco-Teruel et al.

We carried out an admixture analysis of a sample comprising 1,019 individuals from all the provinces of Cuba. We used a panel of 128 autosomal Ancestry Informative Markers (AIMs) to estimate the admixture proportions. We also characterized a number of haplogroup diagnostic markers in the mtDNA and Y-chromosome in order to evaluate admixture using uniparental markers. Finally, we analyzed the association of 16 single nucleotide polymorphisms (SNPs) with quantitative estimates of skin pigmentation. In the total sample, the average European, African and Native American contributions as estimated from autosomal AIMs were 72%, 20% and 8%, respectively. The Eastern provinces of Cuba showed relatively higher African and Native American contributions than the Western provinces. In particular, the highest proportion of African ancestry was observed in the provinces of Guantánamo (40%) and Santiago de Cuba (39%), and the highest proportion of Native American ancestry in Granma (15%), Holguín (12%) and Las Tunas (12%). We found evidence of substantial population stratification in the current Cuban population, emphasizing the need to control for the effects of population stratification in association studies including individuals from Cuba. The results of the analyses of uniparental markers were concordant with those observed in the autosomes. These geographic patterns in admixture proportions are fully consistent with historical and archaeological information. Additionally, we identified a sex-biased pattern in the process of gene flow, with a substantially higher European contribution from the paternal side, and higher Native American and African contributions from the maternal side. This sex-biased contribution was particularly evident for Native American ancestry. Finally, we observed that SNPs located in the genes SLC24A5 and SLC45A2 are strongly associated with melanin levels in the sample.


I did some looking at Dienekes Blog, where I came across the above, and found in a different area a cross post from 23andme. Here's an excerpt that may be relevant:
"On average Latinos had about 70 percent European ancestry, 14 percent Native American ancestry and 6 percent African ancestry."
They explain that the missing 10% is of uncertain admixture.

The problem is that "Latinos" is a very generic term that takes into account anyone who speaks Spanish in the United States. In general, the Caribbean islands received much more African genes through the slave trade than continental Latin America. Conversely, continental Latin American countries retained more Native American genes.

haleaton
08-21-2014, 09:07 PM
The problem is that "Latinos" is a very generic term that takes into account anyone who speaks Spanish in the United States. In general, the Caribbean islands received much more African genes through the slave trade than continental Latin America. Conversely, continental Latin American countries retained more Native American genes.

Very complex "Latino" histories, though often there are records for the last couple centuries or so. In Cuba immigration from Spain was encouraged during early part of the last Century. http://en.wikipedia.org/wiki/Blanqueamiento

Another interesting example, are the Los Angeles Pobladores recruited from Northern New Spain to come to California in 1781. Based on Census records they were on paper mostly indios or African mixtures and also one gentlemen who genealogists believe was from the Philippines.

Mehrdad
08-21-2014, 09:41 PM
The Black in Latin America (http://video.pbs.org/program/black-in-latin-america/)series is really interesting, taught me a thing or two about Cuba, and just as haleaton mentioned there was a large push for European migration in the early part of the 20th century.

Very interesting topic, I've always been interested in Latin American admixtures.