pheomelanin
noun
pheo·mel·a·nin ˌfē-ə-ˈme-lə-nən 
variants or less commonly phaeomelanin
plural pheomelanins also phaeomelanins
: a reddish-yellow sulfur-containing melanin pigment formed in the presence of cysteine
… in people with dark brown or black hair, the pheomelanin is effectively masked by the darker eumelanin.
Erin Brodwin
Erin BrodwinThe marked spectrum of color and diversity of patterns … in mammals arises, unexpectedly, from variation in the quantity, quality, and regional distribution of just two types of pigment—black eumelanin and yellow pheomelanin. Sophie I. Candille et al.
compare eumelanin, neuromelanin Sophie I. Candille et al.
Word History
Etymology
borrowed from German Phäomelanin, from Greek phaiós "a shade between black and white, gray, dark gray" (of obscure origin) + Melanin melanin
Note: The term Phäomelanin was apparently introduced, along with Eumelanin eumelanin, by the biologist Karl Görnitz in "Versuch einer Klassifikation der häufigsten Federfärbungen," Journal für Ornithologie, Band 71 (1923), Heft 1, pp. 127-31. On the meaning of the element phäo-/pheo- see the note at pheochromocytoma.
First Known Use
1924, in the meaning defined above
Medical Definition
pheomelanin
noun
pheo·mel·a·nin
variants also phaeomelanin
ˌfē-ə-ˈmel-ə-nən
: a reddish-yellow sulfur-containing melanin pigment formed in the presence of cysteine
As pH reduces, there is a progressive reduction in tyrosinase activity leading to increased pheomelanin and reddish or blonde hair. Anagha Kumar et al., International Journal of Trichology
Anagha Kumar et al., International Journal of TrichologyModern melanosomes generally carry a mixture of two melanin pigments: dark brown-black eumelanin and red-yellow pheomelanin. Meghan Rosen, Science News
Meghan Rosen, Science NewsThe marked spectrum of color and diversity of patterns that we see in mammals arises, unexpectedly, from variation in the quantity, quality, and regional distribution of just two types of pigment—black eumelanin and yellow pheomelanin. Sophie I. Candille et al., Science
compare eumelanin, neuromelanin Sophie I. Candille et al., Science