NATURAL DARK RED HAIR SKIN
These health benefits increased the likelihood that women would survive pregnancy and birth, successfully passing on genes for light skin and red or blonde hair to their offspring. Vitamin D helps the body absorb and retain calcium, build stronger bones, and protect against inflammation. “There was evolutionary pressure to lose skin pigmentation,” Zorina-Lichtenwalter explains, because lighter skin absorbs more UV, which produces more vitamin D from the limited amount of sunlight in northern regions. Pale coloration bestowed a key advantage to cultures migrating from sunnier regions into northern Europe with its gray skies and short winter days. When they published the study, geneticist Richard Spritz told the media “this is the first time in humans that a specific gene for any common visible characteristic has been identified.” Genetic advantage-and peril More than 80 percent of rosy-haired and/or fair-skinned people carried variations in the MC1R gene but just 20 percent of the brown-haired individuals did. In their 1995 research, Jackson and his colleagues compared 30 Irish and British redheads with the same number of brunettes. “ MC1R is one of several genes that work together to produce dark melanin, and without that switch, you’re going to have light skin,” says Zorina-Lichtenwalter-and easily burn when out in the sun. When exposed to UV light, this variant fails to trigger a switch that changes melanin pigment from yellow/red to the protective brown/black.
In people who have red hair, the skin cells (melanocytes) that produce pigment have a variant receptor on the cell surface. Pheomelanin creates red or blonde locks and confers light skin and freckles. One type, eumelanin, endows brown or black hair. This melanocortin 1 receptor gene, or MC1R, plays a key role in producing melanin, the tan pigment that protects skin from ultraviolet radiation (sunlight) and also colors eyes and skin. The “redhead gene” was discovered in 1995 by a team including Ian Jackson, now a professor emeritus at Scotland’s University of Edinburgh. Ginger coloring in people-as well as horses, dogs, pigs, and other mammals-is conferred by just a handful of genetic mutations that both parents must carry. It is trumped by every other card in the pack.” The genetics of red In her book Red: A History of the Redhead, author Jacky Colliss Harvey characterizes the odds of having a crimson-haired baby this way: “In the great genetic card game, red hair is the two of clubs. Only if both parents are redheads can they be almost certain their baby will have fiery hair, Zorina-Lichtenwalter says. The gene variants involved are recessive, meaning two copies-one from the mother and one from the father-are required to produce a red-haired child. From the fifth century on in what is now southeast Europe and Turkey, the mythological King Rhesus of the ancient Thracians was depicted on Greek pottery with carrot-colored hair and beard. A famous 3,800-year-old Bronze Age mummy, known as the Beauty of Loulan, was unearthed from a desert cemetery in northwestern China with intact sepia-colored hair. Analysis of 50,000-year-old DNA revealed that some Neanderthals were pale-complected redheads.
There’s more research on the variations in human hair color than you might expect, and the science makes it clear that crimson locks are not becoming increasingly rare, nor will they disappear any time soon. As it turns out, it’s not only tabloids that are interested in flame-haired people. To understand why this is so, it’s necessary first to understand why there are redheads in the first place. “Redheads are not going extinct,” says Katerina Zorina-Lichtenwalter, a postdoctoral fellow at the Institute for Behavioral Genetics at University of Colorado, Boulder. While the gene variants that endow flaming locks are rare, redheads are not destined to vanish from the population, despite recurring claims to that effect. That is, in part, because red hair is an exotic trait, occurring in just one or two out of every 100 people.
On the screen and on the street, strawberry blonds and those with auburn tresses attract attention, and always have.
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