ĭifferent hair color phenotypes arise primarily as a result of varying ratios of these two pigments in the human population, although Europeans show the greatest range in pigmentation overall. Inside the melanocytes, tyrosine is converted into L-DOPA and then L-dopaquinone, which in turn is formed into pheomelanin or eumelanin. Two types of pigment give hair its color, black-brown eumelanin and reddish-brown/reddish-yellow pheomelanin, synthesized by melanocytes. identified 13 DNA variations across 11 different genes that could be used to predict hair color. Regulatory DNA is believed to be closely involved in pigmentation in humans in general, and a 2011 study by Branicki et al. The full genetic basis of hair color is complex and not fully understood. See also: Human genetic variation and Race and genetics Early 20th century Standard Fischer-Saller's scale of hair color Genetics and biochemistry of hair color Hair color samples in a box for scientific studies. straight dark hair amongst East Asians, Southeast Asians, Polynesians and Native Americans, a large variety of dark, fair, curly, straight, wavy and bushy hair amongst Europeans, West Asians and North Africans, curly, dark, and uniquely helical hair with Sub Saharan Africans, whilst gray, white or "silver" hair is often associated with age. Some hair colors are associated with some ethnic groups due to observed higher frequency of particular hair color within their geographical region, e.g. Levels of melanin can vary over time causing a person's hair color to change, and it is possible to have hair follicles of more than one color on the same person. The tone of the hair is dependent on the ratio of black or brown eumelanin to yellow or red pheomelanin. Generally, if more melanin is present, the color of the hair is darker if less melanin is present, the hair is lighter. Human hair color is the pigmentation of human hair follicles due to two types of melanin: eumelanin and pheomelanin. For hair colorants, see Hair coloring.Ī variety of human hair colors from top left, clockwise: black, brown, blonde, white, red For hair color of horses, see Equine coat color.
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