Three hundred years ago, three African-born slaves from the Caribbean suffered a sad fate. No one knew who they are, no one knew what they went through, and until recently, no one knew where they came from. Now, researchers extracted and sequenced tiny bits of DNA to figure out where in Africa these people came from when they were captured and enslaved.

Image via MLK Task Force.

“Through the barbarism of the middle passage, millions of people were forcibly removed form Africa and brought to the Americas,” said Carlos Bustamante, one of the researchers, in a news release. “We have long sought to use DNA to understand who they were, where they came from and who, today, shares DNA with those people taken aboard the ships. This project has taught us that we cannot only get ancient DNA from tropical samples, but that we can reliably identify their ancestry. This is incredibly exciting to us and opens the door to reclaiming history that is of such importance.”

Indeed, it’s estimated that roughly 12 million people shipped from West and West Central Africa to the New World between 1500 and 1850, and very little else is known about the origin of these people. Hannes Schroeder, one of the study authors said:

“What’s new about our study is that we were able to obtain genome-wide data from really poorly-preserved skeletal remains using this new technique called whole genome capture. Those remains had essentially been lying on a Caribbean beach for hundreds of years so their preservation was really not good. But by enriching the poorly preserved DNA in those samples we were able to obtain enough data to be able to dig deeper into the genetic origins of those three individuals we analyzed.”

They used a technique called whole-genome capture to isolate enough ancient DNA to properly sequence and analyze – quite a challenging task, as the DNA was in a pretty bad state. They found that one of the former slaves had likely belonged to a Bantu-speaking group in northern Cameroon. The other two shared similarities with non-Bantu-speaking groups in present-day Nigeria and Ghana. All three of them were from between the ages of 25 to 40 years and lived sometime in the late 1600s.

“We were able to determine that, despite the fact that the three individuals were found at the same site, and may even have arrived on the same ship, they had genetic affinities to different populations within Africa,” said Maria Avila-Arcos, one of the researchers, in a news release. “They may have spoken different languages, making communication difficult. This makes us reflect on two things: the dynamics of the trans-Atlantic slave trade within Africa, and how this dramatic, ethnic mingling may have influenced communities and identities in the Americas.”

Journal Reference: Hannes Schroeder et al. Genome-wide ancestry of 17th-century enslaved Africans from the Caribbean. doi: 10.1073/pnas.1421784112