Question

Some newborn black babies have light skin pigmentation but it gets dark with time. Can somebody tell me why this is so?

Answer 1

I don't know the mechanics behind it, but i would assume it had something to do with Melatonin cells in Dermis of your skin.

Answer 2

Im sorry not Melatonin, "Melanocytes" they produce Melanin to paracrin cells. and they're in Epidermis not in Dermis as i previous stateted.

Answer 3

thanks exuras, that helps

Answer 4

i was also thinking of it along the lines of the environment they grow under or something, like if they live under environments with a lot of sunshine and high heat intensity, the melanin darkens, but i think its a question f aging or something related to that, any ideas about that one?

Answer 5

If i understand the question correctly, a albino baby is born but he/she then converts back to the supposibly genetic pigmentation of the skin, based on his parents?

Answer 6

Oh no, that is not the case, and that implies that my assumption is wrong.

Answer 7

Do you mean something in the line of the autoimmune disease "Vitiligo"?

Answer 8

no i doubt, the central substance here is polyphenol oxidase, like how it functions.the thing is i dont know how it works, i.e the mechanisms involved

Answer 9

Enviromental factors, such as UV light does increase pigmentation of the skin, but as you might have noticed it's only temporary. Sooner or later it will revert back to our "genetic" predetermine homeostas pigmentation.
For example, a black person moving to a northern country won't turn white, while white people moving to a southern country would develop darker pigmentation, but if they would move back to the northern country again. Their dark pigmentation would fade relativly quickly. and revert back to their "genetic one".

Im just speculating here but the diffrence would be the following. We both know that cells dies, and are replaced by new cells from stemcells. in this scenario with derm stem cells. They differentiate into new derm cells to replace the old ones. But the new cells will be more white as the skin color you've a genetic predispotion of having based on your parrents genetics.

Well i found some information that might give you the answer you're looking for:
(Peptide they're refering to is the polyphenol oxidase)
"Melanogenesis is controlled by several mechanisms. It is under hormonal control because peptides activating a receptor. A number of other molecules can stimulate the production of melanin, including cholera toxin, metabolites of Vitamin D, and derivatives of retinoic acid. When UV irradiation damages the skin’s DNA, one of the breakdown products of the DNA can also trigger this process."
Source - http://www.wisegeek.com/what-is-melanogenesis.htm

Answer 10

thanks hey!!!