The diverse genetic ancestry of North and South America has been mapped in unprecedented detail revealing key events the history books missed. The study compared the DNA of current Africans and Europeans using more than 4,000 DNA samples to reveal the genetic fingerprints of the slave trade and colonisation. It also highlighted previously unidentified ancestry, such as Basque lineages in South America, along with a ‘surprising’ degree of variation in the ancestry of modern-day Americans. The diverse genetic ancestry of North and South America has been mapped in unprecedented detail, revealing key events the history books missed. The study compared the genes of current Africans and Europeans using more than 4,000 DNA samples to reveal the genetic fingerprints of the slave trade and colonisation. This map reveals the location of donor and recipient populations analysed . The Oxford University team first grouped subsets of people in Africa and Europe who were genetically similar. They were able to separate European genomes into 37 groups. They then compared the data with the genomes from 2,500 people of mixed ancestry from the Americas. The method helped them identify detailed ancestry sources, such as Basque DNA patterns from Spain, rather than France. Overall the group, which also included researchers from University College London and the Universita' del Sacro Cuore of Rome, used DNA sample from 64 different populations. They included people in Barbados, Columbia, the Dominican Republic, Ecuador, Mexico, Puerto Rico and African-Americans in the USA. The study, led by Oxford University, compared the 'donor' African and European DNA with 'recipient' American populations to see where their ancestors came from. 'It was interesting to find so much complexity in the ancestry of American people,’ Professor Cristian Capelli from Oxford University told DailyMail.com. Professor Capellii, who is Italian, was particularly suprised to find evidence of the Basques in Colombia and the Italians in Puerto Rico, as well as the fact that some part of Spain, but not others, contributed Spanish DNA to the Americas . He explained how his team first grouped subsets of people in Africa and Europe who were genetically similar. Using something known as a 'haplotype-based' DNA technique, researchers were able to separate European genomes into 37 groups. They then compared the data with the genomes from 2,500 people of mixed ancestry from the Americas. The method helped them identify detailed ancestry sources, such as Basque DNA patterns from Spain, rather than France. In total, the group, which also included researchers from University College London and the Universita' del Sacro Cuore of Rome, used DNA sample from 64 different populations . They included people in Barbados, Columbia, the Dominican Republic, Ecuador, Mexico, Puerto Rico and African-Americans in the USA. 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 the UK. 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. Meanwhile, the Caribbean Islands of Puerto Rico and the Dominican Republic are genetically similar to each other and distinct from the other populations. The left image shows how much European ancestry is in the Americas, while the left image relates to American ancestry. The bars are colour coded to match the map above. The Basques (light), 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 Oxford team first grouped subsets of people in Africa and Europe who were genetically similar. IThey were able to separate European genomes into 37 groups (pictured). They then compared the data with the genomes from 2,500 American people of mixed ancestry . The ancestors of current-day Yoruba people (left) from West Africa - which is one of the largest African ethnic groups - provided the largest contribution of genes from Africa to all current-day American populations. The most common European genetic source in African-Americans and Barbadians comes from the UK (right) - The most common European genetic source in African-Americans and Barbadians comes from the UK. - The Basques, a distinct ethnic group spread across Spain and France, provided a small but distinct genetic contribution to current-day Continental South American populations. - 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 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 per cent in current-day Barbados. - South Italy and Sicily provided a European contribution to Colombia and Puerto Rico, in line with the history of Italian emigrants to the Americas in the 19th and early 20th century. - One of the African-American groups from the USA had French ancestry, which reflects historical French immigration into the colonial Southern US. The researchers say this probably reflects 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 - which is one of the largest African ethnic groups - provided the largest contribution of genes from Africa to all current-day American populations. 'We can see the huge genetic impact that the slave trade had on American populations and our data match historical records', said study author Dr Garrett Hellenthal from the UCL Genetics Institute, . 'The majority of African Americans have ancestry similar to the Yoruba people in West Africa, confirming that most African slaves came from this region. ‘In areas of the Americas historically under Spanish rule, populations also have ancestry related to what is now Senegal and Gambia. Records show that around a third of the slaves sent to Spanish America in the 17th Century came from this region, and we can see the genetic evidence of this in modern Americans really clearly.' Researchers also found that the proportion of African ancestry varied across the continent, from virtually zero in the Maya people from Mexico to 87 per cent 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. These genetic findings also uncover previously unknown migration. 'We found a clear genetic contribution from the Basques in modern-day Maya in Mexico', said Oxford University's Professor Cristian Capelli. 'This suggests that the Basque also took part in the colonisation of the Americas, coming over either with the Spanish conquistadores or in later waves of migration. 'The differences in European ancestry between the Caribbean islands and mainland American population that we found were also previously unknown. ‘It is likely that these differences reflect different patterns of migration between the Caribbean and mainland America. 'These results show just how powerful a genetic approach can be when it comes to uncovering hidden patterns of ancestry,’ added Professor Capelli. The team now hopes to use the same approach to look at other populations with diverse genetic contributions, such as Brazilians. Professor Capellii, who is Italian, was particularly suprised to find evidence of e Italians in Puerto Rico (bottom right), as well as the fact that some part of Spain, but not others, contributed Spanish DNA to the Americas. Pictured is a graph of some of the regions analysed in the study as well as how much DNA from around the world was found in the populations . South Italy and Sicily 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 .
Scientists compared genes of current Africans and Europeans using 4,000 DNA samples from 64 populations . Study found the most common European genetic source in African-Americans and Barbadians is from the UK . The ancestors of Yoruba people provided the largest contribution of genes from Africa to modern Americans . The study also highlighted previously unidentified ancestry such as Basque genes present in South America .