The technique for obtaining and sequencing ancient DNA in biological samples from thousands of years' worth of archaeological excavations has been perfected by Brazilian researchers at every level.

Svante Pääbo, a Swedish biologist who won the 2022 Nobel Prize in Physiology or Medicine for his research on the genomes of extinct hominids and human evolution, created the method for sequencing the material, which is typically found in bone pieces.

Interestingly, Brazilian researcher Tiago Ferraz obtained his doctorate at the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, where Pääbo serves as director of genetics before transferring his expertise to the University of São Paulo (USP).

Ferraz sequenced ancient DNA while he was still in Germany, leading to the publication of Genomic History of Coastal Societies from Eastern South America in the journal Nature Ecology & Evolution.

Ferraz's work included everything from bone powder extraction, where the DNA is preserved, to data analysis and result interpretation.

Experts from the Senckenberg Center for Human Evolution and Palaeoenvironment at the University of Tübingen, Germany, also contributed to the study, which also included Tiago Ferraz as the first author and André Menezes Strauss, an archaeologist from USP's Museum of Archaeology and Ethnology (MAE) as senior researcher.

“This work has a vital institutional role. It is the first time a Brazilian-led team, alongside so many institutions, has managed to publish a high-impact article in the field of archaeogenetics,” Strauss noted.

A sambaquieiros

The study was based on the genomes of 34 samples that were up to 10,000 years old and came from four different places on Brazil's east coast. The oldest skeleton found in So Paulo, Luzio, which is about 13,000 years old, is among the material.

André Strauss claims that the method helped to solve one of the mysteries in Brazilian archaeology: Did the ancestors of today's indigenous people, known as sambaquieiros, who lived in ancient coastal populations throughout the Brazilian coast descend from a single biological group or from a number of separate peoples?

“Genetic analysis showed that this hypothesis [their origin stemming from distinct peoples] was wrong. The genetic data show they are descended from the same ancestral population, which occupied [what is now Brazil] 16 thousand years ago, just like any other indigenous group in Brazil or the Americas,” Strauss pointed out.

One of the theories, which has since been refuted by archaeogenetics, claimed that two waves of Homo sapiens from Asia inhabited the continent. According to legend, the first wave of migration arrived in this country 14,000 years ago and consisted of people with non-mongoloid morphologies, comparable to modern Australians and Africans, but no descendants. The second wave, from which modern indigenous people are assumed to have descended, is thought to have arrived 12 thousand years ago, and its members are said to have had the physical characteristics of Asians.

However, the findings of the new ancient DNA analysis indicate that there was only one migration. "What we do have is intracontinental migration: people coming here from the Andes, from North America, from South America—but these are local processes. These great migrations, the genetic data, contrary to what had been imagined until now, point toward a single migration from Asia."

Laboratory USP

Ferraz believes that USP's Laboratory of Archaeology and Environmental and Evolutionary Anthropology will be fully operational by the end of 2023 after receiving training for two years at Germany's Max Planck Institute, which is well known for its work on ancient DNA. The facility, which was created in cooperation with the German institute, is the nation's first archaeogenetics laboratory.

The sequencing of ancient DNA might be done in Brazil without the need for facilities abroad if the laboratory is fully operational and has "a solid system for processing samples and decontaminating material," according to the researcher. "We’re adapting the space. We’ve been dealing with various technical and bureaucratic issues,” he said. “We’re putting the finishing touches to it so we can finally open the space and actually work in it, with a more intense work routine."

He continued by saying that the initial goal will be to teach regional scientists how to produce on-site archaeogenetic data. “Now that we’ve brought the technique to Brazil, we’re going to implement it here, do it locally, sequence the individuals, sequence the ancient DNA here in Brazil, and train people to work with it.”