Most human genomes harbor small fragments of Neanderthal DNA, the legacy of prehistoric hanky-panky between our ancestors and their hominid cousins.
For the most part, that inheritance has been detrimental. Research suggests that as much as 10 percent of the human genome was inherited from archaic hominids other than Homo sapiens, but the majority of that material was weeded out by tens of thousands of years of natural selection. The DNA that does remain has been blamed for increasing risk of depression, Type 2 diabetes, Crohn’s disease, lupus, allergies, addiction and more.
