Sex with Neanderthals boosted human immunity Humans, Neanderthals got it on

  • Posted by a hidden member.
    Log in to view his profile

    Aug 28, 2011 12:21 AM GMT
    CBC News

    Posted: Aug 26, 2011

    New genome shows Neanderthal trace in humans


    Neanderthals, such as the one to whom this skull once belonged, died out 30,000 years ago. But many of their immune genes are common among humans outside Africa.

    Nikola Solic/Reuters

    Some immune system genes carried by modern humans came from interbreeding with Neanderthals and other ancient hominins called Denisovans, a new study suggests.

    "The cross breeding wasn't just a random event that happened," said Peter Parham, who co-authored the study published online in Science Express, in a statement. "It gave something useful to the gene pool of the modern human."

    Parham, a professor of microbiology and immunology at California's Stanford University, and his collaborators analyzed a family of immune system genes called human leukocyte antigen (HLA) genes, which are extremely varied and help the body recognize and destroy disease-causing pathogens.

    They sequenced and compared HLA genes from humans with those from:

    Neanderthals, who lived in West Asia and Europe and died out 30,000 years ago.
    Denisovans, a group of hominins who lived in East Asia 30,000 to 50,000 years ago and were discovered in 2008 from a finger bone and a tooth in a cave in Siberia. Those are still the only known Denisovan remains.
    What the researchers found was that humans outside Africa share certain HLA genes with Denisovans and certain HLA genes with Neanderthals. This suggests that these genes entered the human genome through interbreeding with those other hominin groups after humans spread out of Africa 65,000 years ago.

    A Denisovan gene variant called HLA-B*73 was most common in West Asia, leading scientists to believe that was "the most likely site for the fortuitous mating to have taken place," said a Stanford University news release.

    While Neanderthal genes typically make up one to six per cent of the genome of humans from outside Africa, Parham said, Neanderthal and Denisovan HLA genes account for a much higher percentage of HLA gene variants.

    For one class of HLA genes, over half the variants in Europeans, 80 per cent in Asians and 95 per cent of variants in Papua New Guineans originally came from Neanderthals and Denisovans.

    That suggests that these variants gave a survival advantage to humans who carried them, the researchers concluded.

  • Posted by a hidden member.
    Log in to view his profile

    Aug 28, 2011 12:22 AM GMT
    Test Yourself : Are you a Neanderthal?

    This was in the comments section of the above story:

    1. Do your eyebrows meet in the middle? +5

    2. Can you lock your knees in an upright position? -5

    3. Got a chin? If the answer is no, +3

    4. How about a forehead? If not, +3

    5. Is it easy for you to balance a book on your head? +5

    6. Do you ever open beer bottles with your teeth? +10

    7. Are you frequently more comfortable squatting on your heels than sitting in a chair? +5

    8. Is your head attached vertically to your neck? If not, +1 for every five degrees of slope.

    9. Less than five feet tall? +1 for every inch under.

    10. If your lower arm is shorter than your upper arm,+1 for every inch of difference.

    11. Ditto for your lower and upper legs.

    12. Pigeon-toed? +5

    13. Have you ever felt like bashing a postal clerk with a club? You're normal--no points.

    14. Is the space between your big toe and your other toes big enough to hold an apple? +5

    15. Do you regularly eat apples in this fashion? +15

    16. Do people think you're wearing your hair in a bun when you're not? +10

    17. Can you count your vertebrae while wearing two sweaters and an overcoat? +5

    18. Is your nickname "Duke", "Butch", or "Animal"? +3


    0-20 points: You are a virtually pure homosapien. Feel free to build bridges, compose symphonies, and overrun the world.

    20-40 points: A slight Neanderthal strain means that you will occasionally have spells of primitive behavior, crawling around on all fours and whooping wildly. If you live in California, no one will notice.

    40-60 points: You can still function quite well in the modern world, but avoid eating in fancy restaurants lest your table manners give you away.

    60-80 points: Your Pleistocene heritage is predominant. You should consider a career in pro football.

    80-100 points: Unfortunately, your genetic makeup is Grunt City; there is no place for you in human society. A career in politics is recommended.