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This is an accepted version of this page This is the latest accepted revision, reviewed on 28 December 2024. "Skin pigmentation" redirects here. For animal skin pigmentation, see Biological pigment. Extended Coloured family from South Africa showing some spectrum of human skin coloration Human skin color ranges from the darkest brown to the lightest hues. Differences in skin color among ...
Pigmentation disorders are disturbances of human skin color. [1] There may be a loss or reduction, which may be related to loss of melanocytes or the inability of melanocytes to produce melanin or transport melanosomes correctly. [1] Most pigmentation disorders involve the underproduction or overproduction of melanin. [2] [3]
Melanin is a class of pigment responsible for producing color in the body in places such as the eyes, skin, and hair. The process of melanin synthesis (melanogenesis) starts with the oxidation of l-tyrosine to l-dopa by the enzyme tyrosine hydroxylase, then to l-dopaquinone and dopachrome, which forms melanin. [5]
The Fitzpatrick scale has been criticized for its Eurocentric bias and insufficient representation of global skin color diversity. [9] The scale originally was developed for classifying "white skin" in response to solar radiation, [2] and initially included only four categories focused on white skin, with "brown" and "black" skin types (V and VI) added as an afterthought.
A woman with dark skin. Dark skin is a type of human skin color that is rich in melanin pigments. [1] [2] [3] People with dark skin are often referred to as black people, [4] although this usage can be ambiguous in some countries where it is also used to specifically refer to different ethnic groups or populations.
It is an autosomal recessive disorder characterized by a congenital reduction or absence of melanin pigment in the skin, hair, and eyes. The estimated frequency of OCA2 among African-Americans is 1 in 10,000, which contrasts with a frequency of 1 in 36,000 in white Americans. [ 55 ]
— Including at least 25% of patients with darker skin complexion in each study, up from 15% previously; — Evaluating pigmentation of every study participant using at least two different methods, one based on a researcher's evaluation and another based on scientific, light-based measurement of melanin levels in the skin.
Light skin is a human skin color that has a low level of eumelanin pigmentation as an adaptation to environments of low UV radiation. [1] [2] Due to migrations of people in recent centuries, light-skinned populations today are found all over the world.