Our allergies come from genes inherited from Neanderthal man

health - Allergies afflicting modern man would come from inherited genes of Neanderthals and Denisovians, extinct cousins of humans,

following crosses with these species there are approximately 40,000

years, revealed Thursday two studies.

these prehistoric couplings are that all modern humans with the exception of Africans have inherited from 1 to 6% of genes of ancient hominid as the Denisova and Neanderthal man, tribes who lived in Siberia.

three of these genes are among those from these two species, the most common found in modern men and play an important role in the immune system, explain these two studies published in the journal

American Journal of Human Genetics

.

immune excessive sensitivity this discovery suggests that genetic inheritance confers an advantage in the evolution of humans in boosting their immune system.

but these genes are also responsible for excessive sensitivity of the immune system, which causes allergies. Holders are thus more prone to asthma, hay fever and other allergies.

these genes themselves are probably transmitted to modern humans when the first groups have left Africa there are about 50,000 years to come to Europe. They had sex with Neanderthals already established in Eurasia.

"our study shows that crosses with archaic humans have had practical implications for modern humans, whose most obvious has been our adaptation to the environment by improving our resistance to pathogens and our metabolism to digest new food," says Janet Kelso, of the Max Planck Institute in Germany, lead author of one of the studies.

adaptation to the climate and

food "the Neanderthals lived in Europe and Western Asia for 200,000 years before the arrival of modern humans." "They were probably well adapted to the climate, food and pathogens and mating with them, us modern humans have inherited from these advantageous adaptations", she continues.

Janet Kelso has scanned the genomes of modern humans to detect genes of Neanderthals or human from Denisova. Two of the three genes of the immune system corresponded to DNA from Neanderthal and the third to that of Denisova.

the most common of these genes was found in any newly population, the second especially among Asians and the third, rarer and more similar to the Denisova DNA in a small group of Asians.

Dr Quintana-Murci, of the Pasteur Institute in Paris and lead author of the second study, studied 1500 active genes in the immune system. It was determined that most adaptations occurred 6000-13,000 years ago, when humans went from lifestyle hunter-gatherer to agriculture.