Have you ever wondered why you have hair on your feet, but not on your feet?
Or why do we have a lot of hair on our head but not one hair on the palms of our hands?
The question has been for many years for doctors, researchers and other scientists of complex human body machines.
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For decades, science was limited to considering that it was a evolutionary properties some animals, but the physiological explanation of how it is produced is a recent question.
Scientists from the University of Pennsylvania School of Medicine have been researching this "mystery" for years and now claim to have an answer.
Study published in the journal Journal Cell Reports, indicates that the "culprit" not We get hair in certain areas of our body is a special kind of molecule, for multiple signals, proteins.
According to the researchers, it is about this Dickkopf 2 (DKK2), which blocks the so-called. "WNT signaling pathways", cellular channels that, among other things, are responsible for initiating hair growth.
"In this study, we demonstrate that skin in unknowable areas naturally produces an inhibitor that prevents WNT from doing its job," he said in a journal. Newsweek Sarah E. Millar, one of the investigators.
"We know that WNT signaling is essential for the development of hair follicles, blocking hairless hair and activating it causes more hair to be formed," he said.
But why some animals have hair on most of their bodies, and the other does not?
Things of evolution
The study suggests that, as it has been known for years, evolutionary adaptation.
The research suggests that some animals evolved to produce DKK2 in certain parts of their bodies helping them to better survive their environment.
For example, the hairless hand would serve more to hold instruments or other tasks, while the absence of wild boots might help to walk better.
However, in cold climates it would be better if they are coated, as in the case of polar bears.
To reach these conclusions, the team analyzed the skin of mice (which, like humans, have no hair on their plants) and compares them to other working animals, such as rabbits.
When comparing the DKK2 levels between the two species, they found that the amount of protein is significantly lower in the skin of animals having hair on the tabs.
Meanwhile, the level of the molecule was considerably higher in areas where hair does not grow than in the finest areas.
The study shows that in these areas there is no WNT signaling, hair generator, but the protein is blocked.
Scientists hope the findings will be used for new research on hair growth, treatment of some diseases or future treatments for people who have suffered severe burns or accidents.
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