Previous studies into the ancestry of human beings revealed that humans had cross bred with Neanderthals and Denisovans in order to take their populace forward. In fact research into the DNA of modern human beings of China, Russia and large parts of Asia, Europe and Africa revealed that people living in these regions still carry a certain percentage of Denisovan and Neanderthal DNA. But for people living in the Pacific Islands, the DNA signature shows an unknown ancestor, perhaps a group of hominids that existed around the same time as Neanderthals and Denisovans but later got extinct.
The study was carried out by Anderson Cancer Research Center, University of Texas. Ryan Bohlender, a statistical geneticist,estimated that Melanesian people should have about 6% Denisovan DNA. However, people from this region have only 1.11% Denisovan DNA, leading researchers to speculate that they contain DNA from another group of unknown hominids. This is a significant discovery in mapping human genetics since the earliest possible time.