Whole genome sequences provide a genetic snapshot of ancient indigenous peoples who were decimated by European military campaigns


The first complete genome sequences of the ancient people of Uruguay provide a genetic snapshot of the region’s indigenous populations before they were decimated by a series of European military campaigns. Nexus PNAS published the research, led by anthropologists from Emory University and the University of the Republic, Montevideo, Uruguay.

“Our work shows that the indigenous peoples of ancient Uruguay exhibit an ancestry that has not previously been detected in South America,” says John Lindo, co-corresponding author and Emory Assistant Professor of Anthropology specializing in DNA. ancient. “It contributes to the idea that South America is a place where multi-regional diversity existed, instead of the monolithic idea of ​​a single Native American race across North and South America.”

The analyzes relied on a DNA sample from a man dating back 800 years and another from a woman dating back 1,500 years, both well before the 1492 arrival of Christopher Columbus in the Americas. The samples were taken from an archaeological site in eastern Uruguay by co-corresponding author Gonzalo Figueiro, a biological anthropologist at the University of the Republic.

The results of the analyzes showed a surprising connection with the ancient individuals of Panama – the land bridge that connects North and South America – and with eastern Brazil, but not with modern Amazonians. These finds support the theory proposed by some archaeologists of separate migrations in South America, one of which led to the Amazonian populations and another which led to the populations along the East Coast.

“We have now provided genetic evidence that this theory may be correct,” Lindo said. “This runs counter to the theory of a single migration that split at the foothills of the Andes.”

Archaeological evidence of human settlement in the region now known as Uruguay, located on the Atlantic coast in southern Brazil, dates back more than 10,000 years. European colonizers first made contact with the indigenous peoples of the region in the early 1500s.

During the 1800s, colonizers launched a series of military campaigns to exterminate indigenous peoples, culminating in what is known as the Salsipuedes Creek Massacre in 1831, which targeted an ethnic group called the Charrúa. At that time, the authors write, the term Charrúa was widely applied to the remains of various groups of hunter-gatherers in the territory of Uruguay.

“Thanks to these first complete genome sequences of indigenous peoples in the region before the arrival of Europeans, we were able to reconstruct at least a small part of their genetic prehistory,” says Lindo.

The work opens the door to today’s Uruguayans seeking to genetically relate to populations that existed in the region before the arrival of European colonizers. “We would like to collect more DNA samples from ancient archaeological sites across Uruguay, which would allow people living in the country today to explore a possible genetic connection,” Lindo said.

Lindo’s ancient DNA lab specializes in mapping little-explored human lineages of the Americas. Most of the older DNA labs are located in Europe, where the cooler climate has better preserved specimens.

Less attention has been given to sequencing ancient DNA from South America. One reason is that warmer and wetter climates across much of the continent have made it more difficult to collect usable ancient DNA specimens, although advances in sequencing technology are helping to weed out some of these. restrictions.

“If you’re of European descent, you can have your DNA sequenced and use that information to work out where your ancestors came from down to specific villages,” Lindo says. “If you are descended from Native Americans, you may be able to learn that part of your genome is Native American, but you are unlikely to be able to trace a direct lineage because there are not enough ancient DNA references. available.”

To further complicate the picture, he adds, the massive disruption caused by the arrival of Europeans as many civilizations were destroyed and entire populations killed.

Working closely with indigenous communities and local archaeologists, Lindo hopes to use advanced DNA sequencing techniques to create a free online portal with a growing number of ancient DNA references from the Americas, to help people to better explore and understand their ancestry.

Co-authors of the current paper include Emory senior Rosseirys De La Rosa, Andrew Luize Campelo dos Santos (Federal University of Penambuco, Recife, Brazil), Monica Sans (University of the Republic, Montevideo, Uruguay), and Michael De Giorgio ( Florida Atlantic University).

The work was funded by a CAREER grant from the National Science Foundation.


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