posted August 26, 2011 01:26 PM
This is an interesting piece
I'm not sure where it should go
so for the time being I'll put it here.
Ms Juni, Ms Charmaine,
please feel free to relocate this thread if need be.
Sexual relations between ancient humans and their evolutionary cousins are critical for our modern immune systems, researchers report in Science journal.
Mating with Neanderthals and another ancient group called Denisovans introduced genes that help us cope with viruses to this day, they conclude.
Previous research had indicated that prehistoric interbreeding led to up to 4% of the modern human genome.
The new work identifies stretches of DNA derived from our distant relatives.
In the human immune system, the HLA (human leucocyte antigen) family of genes plays an important role in defending against foreign invaders such as viruses.
The authors say that the origins of some HLA class 1 genes are proof that our ancient relatives interbred with Neanderthals and Denisovans for a period.
"Getting these genes by mating would have given an advantage to populations that acquired them”
At least one variety of HLA gene occurs frequently in present day populations from West Asia, but is rare in Africans.
The researchers say that is because after ancient humans left Africa some 65,000 years ago, they started breeding with their more primitive relations in Europe, while those who stayed in Africa did not.
EtA: I didn't relize Lexx was moderating this forum also, Ms Lexx the above includes you too