Have you ever wondered why you have hair on your feet, but not on your legs?
Or why do we get a lot of hair on the head, but not a single hair on our palms?
This issue has for years been a matter for doctors, researchers and other scientists in the complex mechanism of the human body.
For decades, science was confined to the idea that it is a evolutionary feature from some animals, but a physiological explanation of how it is produced until recently was a question.
Researchers at the University of Pennsylvania School of Medicine have been studying this "secret" for years and now claim to be given a response.
The study published in the magazine journal Cell Reports, indicates that the "culprit" is not We get the hair in certain areas of our body, there is a special molecule type to get more signals, protein.
According to the researchers, this is about Dikkkopf 2 (DKK2) blocking the so-called "WNT signaling paths", mobile channels that are among other things responsible for activating hair growth.
"In this study, we show that skin in colorless areas naturally creates an inhibitor that prevents WNT from doing its job," he told the magazine. Newsweek Sarah E. Millar, one of the authors of the study.
"We know that WNT alarms are essential for the development of hair follicles, blocking it creates hair and its activation causes more hair growth," he said.
But why do some animals have hair in most of their bodies, but others do not?
The study shows that, as has been known for years, evolutionary adaptation.
The study studies that some animals evolved to detect some parts of the body DKK2 help them better survive in their environment.
Thus, for example, hair would serve more hands to hold instruments or other tasks, but lack of needles on the legs would help walk better.
Cold climates, however, would be better if they were covered, for example, in the case of polar bears.
To reach these conclusions, the team analyzed the skin of the mouse (which, like humans, did not have hair on the plants), and compared it to other animals, such as rabbits.
When comparing the levels of DKK2 between the two species, they found that the amount of protein was significantly lower in the skin of the animals having legs.
At the same time, the molecular level was much higher in areas where hair does not develop, rather than in the most parts of the mouth.
The study indicates that these areas do not have WNT signal paths, such as hair-generators, but proteins block them.
Now researchers hope that this result can be used for new studies on hair growth, for the treatment of certain diseases, or for further treatment in people who are seriously dead or have an accident.
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