pheomelanin


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Related to pheomelanin: Eumelanin

phe·o·mel·a·nin

(fē'ō-mel'ă-nin),
A type of melanin found in red hair; it contains sulfur and is alkali soluble; elevated levels are found in the rufous type of oculocutaneous albinism. Compare: eumelanin.
[G. phaios, dusky, + melas (melan-), black]

pheomelanin

yellow to red-brown pigment produced by melanocytes. See also eumelanin.
References in periodicals archive ?
Humans produce melanin in 3 forms: neuromelanin (B), eumelanin (both brown-black) (C), and pheomelanin (golden yellow -red) (D).
That analysis not only reported one of the first demonstrations of pheomelanin (the brown version of melanin) in non-vertebrates, but it also found that the grasshoppers kept on brown soil were rich in pheomelanin, while the grasshoppers kept on gray stones were rich in eumelanin (the black version of melanin) (see Galvan et al.
In an attempt to unearth the factors favouring the evolution of pheomelanin in spite of its costs, Ismael Galvan and Anders P.
They specifically excluded women with chemical hair treatment and utilised spectrophotometric hair analysis to confirm the pheomelanin proportion.
An easy-to-run method for routine analysis of eumelanin and pheomelanin in pigmented tissues.
Skin contains two kinds of pigments, or melanins: pheomelanin, which is reddish or yellow, and eumelanin, which is dark and brownish.
In a large number of mammalian species, the coat color diversity is mainly determined by the relative amount of the two basic melanins, eumelanin (black/ brown) and pheomelanin (yellow/red), which are genetically controlled by the extension (E) and agouti (A) loci, respectively [5].
Certain defective MC1R variants are associated with a phenotype that shows red hair, fair skin, and predominance of nonphotoprotective pheomelanin ("red/yellow" melanin).
That tiny difference prevents the tiger from making the reddish and yellow pheomelanin pigments, but does not affect the production of the black pigment eumelanin.
Light-skinned redheads with freckles and an inability to tan have trouble producing the black-grown pigment eumelanin, which absorbs harmful UV rays - instead producing the red-yellow pigment pheomelanin which provides a weak UV shield.
Individuals with red hair have a predominance of pheomelanin in hair and skin and/or a reduced ability to produce eumelanin, which may explain why they fail to tan and suffer from increased cutaneous UV sensitivity and why UV irradiation is more dangerous for them.