Researchers analyzed the genetic material of hundreds of Nigerians and Sierra Leoneans and found that they had “ghost DNA” from an unknown ancestor.
Recently, the American academic journal “Frontiers of Science” published the latest research results on “ghost DNA”, making the story of human origins more complicated. “Human evolution is incredibly complex, and we’re just scratching the surface of it,” biologist Sriram Sankararaman of the University of California, Los Angeles, told NPR.
Sharon Browning, a professor of biostatistics at the University of Washington, has studied hybrids of Denisovans and Homo sapiens. She pointed out that “ghost DNA” often appears in the genetic material of modern people. “This tells us that those ancient populations still influence modern humans.”
Sankararaman said that scientists currently do not know the specific role of these mysterious genetic materials. “Are they just randomly appearing in our genome? What adaptive (evolutionary) advantage do they have? Or do they have any adverse effects? These are all questions worth thinking about.” He pointed out that there is evidence that modern humans outside West Africa There is also “ghost DNA” in the body. “When we obtain human genome sequences at different points in time and from different parts of the world, we may discover some unidentified ‘ghost’ populations.”
Browning believes that the “ghost DNA” discovered this time may come from multiple populations. “In Africa, we have yet to determine exactly how many ancient tribes participated in the formation of human genes. But the emergence of this mysterious gene tells us that human genes do exist and may come from more than one ancient group.”
Due to climate influence, it is much more difficult to obtain fossil samples in West Africa than in other regions. Therefore, this study currently lacks fossil evidence. Scientists are still studying where the mysterious owners of “ghost DNA” come from and what they experienced. They may have become extinct, or they may have eventually fully integrated into modern humans.