Recent genetic analysis has revealed that during the last ice age, humans migrating from Asia via the Beringland Bridge experienced three significant population divisions upon arriving in America. This migration is described by researchers as “the longest human journey from Africa,” resulting in a group that settled in Patagonia approximately 14,500 years ago.
A study published on Thursday, May 15th, in the journal Science details an international team’s analysis that includes 1,537 individuals from 139 distinct ethnic groups, referred to as Early Americans.
According to study co-author Hie Lim Kim, a professor of population genomics at Nanyang University of Technology in Singapore, “Many indigenous people are small and genetically unique. One of the main findings of our study is the extremely low genetic diversity.”
By analyzing genetic material from Genomeas 100K, a consortium that holds data from Asian populations whose ancestors arrived in the Americas, Kim and her team were able to trace the genetic heritage of American indigenous peoples and pinpoint three key periods of divergence.
The initial population division took place between 26,800 and 19,300 years ago, as described by the researchers. This period marked the split of Indigenous Americans from the populations of North Eurasia, coinciding with evidence of Native American presence at the ancient Footprints site in white sands, New Mexico, dating back to approximately 23,000 to 21,000 years ago.
Related: The ancient indigenous lineage of the Blackfoot Union dates back 18,000 years to the last ice age, DNA reveals
Following this, the next major population division occurred between 17,500 and 14,600 years ago, during which indigenous peoples in North America diverged, with some groups moving southward. This Mesoamerican lineage subsequently divided into four native genetic strains around 13,900 years ago.
“Our estimates align remarkably well with archaeological records of the Patagonian people,” stated Kim, noting that these populations were established at the southernmost tip of the continent by approximately 14,500 years ago. “Once they spread across different regions of South America, it took time for genetic differences to emerge between populations,” she explained.
Notably, the study identified a decline in genetic diversity among populations upon entering the new continent tens of thousands of years ago.
A significant loss discovered by the research team was related to changes in the human leukocyte antigen (HLA) gene, which plays a crucial role in immune health. Previous studies have highlighted that high HLA gene diversity in populations is vital, especially in regions like Southeast Asia where disease prevalence is high. However, the team found significantly lower diversity in the HLA gene among Indigenous South Americans.
Researchers aim to bring attention to the unique medical needs of contemporary indigenous populations. “Much of the existing medical research is based on European populations, frequently overlooking Indigenous peoples,” Kim emphasized. “It is essential to create targeted healthcare and disease prevention strategies capable of addressing specific genetic profiles.”
Source: www.livescience.com