The first people to migrate to the Americas carried a unique genetic relic from extinct human groups, Neanderthals and Denisovans. This archaic variation may have helped early Americans fight diseases in their new environment. A recent study found that 1 in 3 Mexicans alive today carry a Denisovan-specific gene variant, which is beneficial for immune function.
Researchers analyzed the MUC19 protein-coding gene and discovered that it was passed down from Neanderthals to modern humans via Denisovans. This genetic variation was common among Indigenous Americans, with higher frequencies found in Mexicans, Peruvians, and Colombians. The study suggests that this gene variant may have provided an evolutionary advantage, allowing early Americans to adapt to their new environment more efficiently.
The researchers’ findings provide insight into human evolution and the complex interplay between different human groups. By studying this genetic relic, scientists can gain a better understanding of how humans developed immunity to diseases in response to new environmental challenges.
As people expanded into the Americas, they drew upon the genetic variants they gained from other human groups, allowing them to develop new mutations more quickly. The study’s authors propose that this genetic exchange may have contributed to the development of immune responses and disease resistance in early Americans.
Further research is needed to determine the function of the Denisovan MUC19 gene and how it affects protein function. However, the discovery of this genetic relic highlights the importance of studying human evolution and the complex history of human migration and interaction with other species.
Source: https://www.livescience.com/archaeology/human-evolution/the-first-americans-had-denisovan-dna-and-it-may-have-helped-them-survive