February 19, 2005

African ancestry in Buenos Aires

A new article quantifies the African admixture in the population of Buenos Aires from Argentina. The admixture is estimated at 2.2% overall, but is concentrated on only 10% of the total population. These results indicate the great reduction of the black element in Buenos Aires, although it did not disappear entirely.

American Journal of Physical Anthropology (Early View)

African ancestry of the population of Buenos Aires

Laura Fejerman et al.

The population of Argentina today does not have a visible black African component. However, censuses conducted during most of the 19th century registered up to 30% of individuals of African origin living in Buenos Aires city. What has happened to this African influence? Have all individuals of African origin died, as lay people believe? Or is it possible that admixture with the European immigrants made the African influence invisible? We investigated the African contribution to the genetic pool of the population of Buenos Aires, Argentina, typing 12 unlinked autosomal DNA markers in a sample of 90 individuals. The results of this analysis suggest that 2.2% (SEM = 0.9%) of the genetic ancestry of the Buenos Aires population is derived from Africa. Our analysis of individual admixture shows that those alleles that have a high frequency in populations of African origin tend to concentrate among 8 individuals in our sample. Therefore, although the admixture estimate is relatively low, the actual proportion of individuals with at least some African influence is approximately 10%. The evidence we are presenting of African ancestry is consistent with the known historical events that led to the drastic reduction of the Afro-Argentine population during the second half of the 19th century. However, as our results suggest, this reduction did not mean a total disappearance of African genes from the genetic pool of the Buenos Aires population.


No comments: