Scientists and Neanderthals mated, scientists said.  Scientists have long has long thought that Neanderthal genes that have been instilled in human DNA are not functional.  However, new research increasingly suggests that immune system genes in modern humans seem to have been passed down by Neanderthals and other archaic relatives.

Scientists also said that these gene variants greatly benefited humans.  Study author and postdoctoral researcher Laurent Abi-Rached said that the DNA a very profound functional impact in the immune systems of modern humans.

Neanderthals were population of hunter-gatherers who populated our Earth until 30,000 years ago.

Biologists at the Max Planch Institute for Evolutionary Anthropology in Leipzig, Germany estimated that one to four percent of modern Eurasian genomes are founded in our hominid predecessors.

In the study, scientists evaluated genes on chromosome 6 called human leukocyte antigen class I genes, which enable HLA proteins that help the immune system detect anomalies including cancer. 

The scientists said that more than 50 percent of genetic variants in one HLA gene seen in Europeans are related to Denisovan, a type of hominid, DNA.  This number increased to 70 percent in Asians and 95 percent in people from New Guinea.

Researchers explained that the spread of these gene variants likely gave some early modern humans comparative advantages over other early modern humans. 

The findings were published in the journal Science Thursday.