Researchers at the Stanford University Medical Center have extracted and sequenced tiny bits of DNA remaining in the teeth of 300-year-old skeletons in the Caribbean. From this data, they were able to determine where in Africa the individuals likely lived before they were captured and enslaved. Here are excerpts:
More than 300 years ago, three African-born slaves died on the Caribbean island of Saint Martin. No written records memorialized their fate, and their names and precise ethnic background remained a mystery. For centuries, their skeletons were subjected to the hot, wet weather of the tropical island until they were unearthed in 2010 during a construction project in the Zoutsteeg area of the capital city of Philipsburg.
Now researchers at the Stanford University School of Medicine and the University of Copenhagen have extracted and sequenced tiny bits of DNA remaining in the skeletons’ teeth. From this data, they were able to determine where in Africa the individuals likely lived before they were captured and enslaved.
The research marks the first time that scientists have been able to use such old, poorly preserved DNA to identify with high specificity the ethnic origins of long-dead individuals. The finding paves the way for a greater understanding of the patterns of the trans-Atlantic slave trade, and may transform the general practice of genealogical and historical research.
“Through the barbarism of the middle passage, millions of people were forcibly removed from Africa and brought to the Americas,” said Carlos Bustamante, PhD, professor of genetics at Stanford. “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.”
A new tool
The researchers used a technique recently devised in the Bustamante laboratory called whole-genome capture to isolate enough ancient DNA from the skeletons to sequence and analyze. In this way, they learned that one skeleton was that of a man who 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.
Bustamante is co-author of a paper describing the research. It will be published online March 9 in the Proceedings of the National Academy of Sciences. The study was led by Hannes Schroeder, PhD, a molecular anthropologist from the University of Copenhagen, and Stanford postdoctoral scholar Maria Avila-Arcos, PhD. The research was initiated in Denmark, and the senior author of the study is Thomas Gilbert, PhD, of the University of Copenhagen.
Bustamante is well-known for his studies of the ethnic background of native Mexicans and Caribbean dwellers, as well as for using genomics to study the patterns of human migration from North Africa to southern Europe. [. . .]
For full article, see http://www.sciencedaily.com/releases/2015/03/150309155523.htm