Albinism reveals itself through a lack of melanin or coloring in the skin, hair and eyes.

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Dark feathers contain the pigment melanin, which protects feathers against the damaging effects of abrasion and UV radiation.

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People with albinism are born with genes that do not make the normal amounts of the pigment called melanin.

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Some people with this disorder never experience changes in pigmentation, but others begin to produce melanin during childhood and adolescence.

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Intriguingly, that did not apply to birds that used melanin, another pigment, in their plumage, nor to those that employed iridescence which is a result of the structure of feathers, rather than their chemistry.

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The first source said Jackson's body was "lily white from head to toe, " perhaps the result of vitiligo -- a condition that causes the skin to lose melanin and produce slowly enlarging white patches.

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In addition, vitamin D can be produced by the skin with sunlight exposure, but this ability decreases with age and varies considerably by geography, time of day or year, skin melanin content (darker skin produces less vitamin D) and sunscreen use.

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