Genomic insight into the origins and dispersal of the Brazilian Coastal Natives

In the 15th century, approximately 900,000 Native Americans, mostly Tupí-speakers, lived on the Brazilian coast. By the end of the 18th century, the coastal native populations were declared extinct. The Tupí arrived on the east coast after leaving the Amazonian basin approximately 2,000 years before present; however, there is no consensus on how this migration occurred - toward the northern Amazon and then directly to the Atlantic coast, or heading south into the continent, and then migrating to the coast. Here we leveraged genomic data from one of the last remaining putative representatives of the Tupí coastal branch, a small, admixed, self-reported Tupiniquim community, as well as data of a Guaraní Mbyá native population from Southern Brazil and of three other native populations from the Amazonian region. We demonstrated that the Tupiniquim Native American ancestry is not related to any extant Brazilian Native American population already studied and thus they could be considered the only living representatives of the extinct Tupí branch that used to settle the Atlantic Coast of Brazil. Furthermore, these data show evidence of a direct migration from Amazon to the Northeast Coast in pre-Columbian time, giving rise to the Tupí Coastal populations, and a single distinct migration southward that originated the Guaraní people from Brazil and Paraguay. This is the first study to elucidate the population dynamics and diversification of the Brazilian Natives at a genomic level, which was made possible by recovering data from the Brazilian coastal population through the genomes of mestizo individuals.EGA study EGAS00001004036