It is truly amazing that we know so much now about our early days. For example, Africans do not have DNA which is specifically derived from Neanderthals, whereas people in the rest of the world do carry a small amount. This confirms the picture of human history derived from studying fossils. Neanderthal bones have not been found in Africa, so it isn’t surprising that their DNA is not there either. The fact that non-Africans have some of the DNA found in Neanderthal bones confirms that which geneticists knew from other studies: we have two distinct groups of human ancestors—those who left Africa in ancient times and those who stayed.
Quoted from an essay on Biologos