The University of Oxford has conducted a study of the “Complex genetic ancestry of Americans,” where the genes of North and South Americans with European and African representation were compared, and found the genetic links of the colonisation of the Americas and the slave trade.
Researchers involved in the study analysed over 4,000 DNA samples crossing a broad spectrum of populations of the Americas, Europe and Africa. By tracking DNA of the originating populations with that of the populations in the Americas, Europe and Africa, they found that “the genetic profile of Americans is much more complex than previously thought,” according to study leader Professor Cristian Capelli from the Department of Zoology at Oxford University.
The study found that:
- “While Spaniards provide the majority of European ancestry in continental American Hispanic/Latino populations, the most common European genetic source in African-Americans and Barbadians comes from Great Britain.
- The Basques, a distinct ethnic group spread across current-day Spain and France, provided a small but distinct genetic contribution to current-day Continental South American populations, including the Maya in Mexico.
- The Caribbean Islands of Puerto Rico and the Dominican Republic are genetically similar to each other and distinct from the other populations, probably reflecting a different migration pattern between the Caribbean and mainland America.
- Compared to South Americans, people from Caribbean countries (such as the Barbados) had a larger genetic contribution from Africa.
- The ancestors of current-day Yoruba people from West Africa (one of the largest African ethnic groups) provided the largest contribution of genes from Africa to all current-day American populations.
- The proportion of African ancestry varied across the continent, from virtually zero (in the Maya people from Mexico) to 87% in current-day Barbados.
- South Italy and Sicily also provided a significant European genetic contribution to Colombia and Puerto Rico, in line with the known history of Italian emigrants to the Americas in the late 19th and early 20th century
- One of the African-American groups from the USA had French ancestry, in agreement with historical French immigration into the colonial Southern United States.
- The proportion of genes from European versus African sources varied greatly from individual to individual within recipient populations.”
The press release at Eurekaalert.com provides more information.