Red Heads!
Red Heads
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Red Heads Historical Distribution
Red-headed, blue-eyed Central Asian (Tocharian?) and East-Asian Buddhist monks, Bezaklik, Eastern Tarim Basin, 9th-10th century. Estimations on the original occurence of the red haired gene vary from 20,000 to 100,000 years ago. Some commentators have speculated that red-headed and freckled humans share some heritage with Neanderthals. However, other researchers disagree, and the scientists who conducted the study claim this is a misinterpretation of their findings.A fragment by Xenophanes describes the Thracians as blue-eyed and red-haired, and Herodotus described the "Budini" (probably Udmurts and Permyak Finns) as being predominantly redheaded. The Berber and Kabylie populations of northern Algeria have occasional red heads. Red hair was also found in Asia, notably among the Tocharians. The 2nd millennium BC Tarim mummies in China were found with red and blond hair.
Boudica, the famous Celtic queen of the Iceni, was said by the Greek historian Dio Cassius to: "be tall and terrifying in appearance ... a great mass of red hair fell over her shoulders". The Roman Tacitus commented on the "red hair and large limbs of the inhabitants of Caledonia Scotland" (The Life of Agricola, Ch. 11), which he linked with some red haired German/Belgic Gaulish tribes.
On the left, a red-headed girl in Kalasha, Pakistan.Today, red hair is most commonly found at both the west and eastern fringes of modern Europe. It is associated with those in Britain and Ireland (more specifically the Scots, Irish, Welsh and Cornish). The highest proportion of redheads is found in Scotland and Ireland, where as many as 10% have ginger or strawberry blond hair, while it is thought that up to 35% carry a recessive "ginger gene". However, dark red or reddish-tinged hair is also found in other Caucasian populations particularly in Scandinavia.
In Asia, redheads can be found today from North India, Iran and Pakistan, where it can be found most commonly amongst those of Iranian descent, such as the Pashtuns, all the way to Japan.
Red Heads Biochemistry and genetics of red hair
MP Robin Cook was one of many redheaded Scots.The biochemistry of red hair, discovered in 1997, appears to be associated with the melanocortin-1 receptor, which is found on chromosome 16. The MC1R recessive gene which gives people red hair and fair skin is also associated with freckles, though it is not uncommon to see a redhead without freckles. 80% of redheads have a MC1R gene variant, and the prevalence of these alleles is highest in Scotland and Ireland.The genetics of red hair are now being uncovered, together with connections between red hair and melanoma, skin disorders in general, and different reactions to anaesthesia. There is evidence for genetic linkage of eye color with other hair colors such as brown hair, although MC1R is not linked to eye color. The inheritance of red hair is close to what geneticists describe as an autosomal recessive mode of inheritance. This means that the parents of red-haired children may carry the gene for red hair but not have red hair themselves.
There is also evidence that red hair may be an example of incomplete dominance. This means that when only one copy of the red hair allele is present, red hair may blend with the other hair color, resulting in different types of red hair including strawberry blond (red-blonde) and auburn (red-brown). In studies by Harding, et al. (2000), the alleles Arg151Cys, Arg160Trp, Asp294His, and Arg142His on MC1R, are shown to be recessives for the red hair phenotype.
Evolution of red hair
Red hair is the rarest type of natural hair color in humans and the reasons for its occurrence are unclear. The pale skin associated with red hair may be of advantage in far-northern climates where sunlight is scarce. Studies by Bodmer and Cavalli-Sforza (1976) hypothesized that lighter skin pigmentation prevents rickets in colder latitudes by encouraging higher levels of Vitamin D production and also allows the individual to retain heat better than someone with darker skin. Rees (2004) suggested that the vividness and rarity of red hair may lead to it becoming desirable in a partner and therefore it could become more common through sexual selection.Harding et al (2000) proposed that red hair was not the result of positive selection but rather occurs due to a lack of negative selection. In Africa, for example, red hair is selected against because high levels of sun would be harmful towards fair skin. However, in Northern Europe this does not happen and so redheads can occur through genetic drift.
Red Head Sensitivity to ultraviolet light
Red hair is also associated with fair skin color and sensitivity to ultraviolet light. On MC1R, the alleles that code for red hair occur close to the alleles that impact skin color, so it seems that the phenotypic expression for lighter skin and red hair are interrelated. Melanin in the skin aids UV tolerance through suntanning, but a typical redhead lacks melanin and is more likely to get sunburn. Studies by Healy et al. (2000) show that red hair alleles in MC1R effect increased freckling and decreased tanning ability. Rees (2004) found that Europeans that are heterozygous for red hair exhibit increased sensitivity to UV radiation.Red hair and its relationship to UV sensitivity are of interest to many melanoma researchers. Sunshine can both be good and bad for a person's health and the different alleles on MC1R represent these adaptations. It also has been shown in studies by Rees (2002a, 2002b) that individuals with pale skin are highly susceptible to a variety of skin cancers such as melanoma, basal cell carcinoma, and squamous cell carcinoma.
Red Head Sensitivity to pain
Two studies have demonstrated that redheads have differential sensitivity to pain compared to non-redheads, but they differ as to the direction of the effect. A study by Liem et al. found that redheads are more sensitive to thermal pain. However, a study by Mogil et al. found that redheads are less sensitive to pain from electrical stimuli, and that mutant mice with non-functional melanocortin-1 receptors are less sensitive to pain from multiple modalities.In people with red hair, the cells that produce skin and hair pigment have a dysfunctional melanocortin 1 receptor. Edwin Liem (researcher at the Outcomes Research Institute of the University of Louisville, US) says this dysfunction triggers the release of more of the hormone that stimulates these cells, but this hormone also stimulates a brain receptor related to pain sensitivity.
Researchers have found that redheads require greater amounts of anesthesia, but other research shows that women with naturally red hair require less of the painkiller pentazocine than do either women of other hair colors or men of any hair color. A study conducted by Jeffrey Mogil and colleagues showed red-headed women had a greater analgesic response, to that particular pain medication, than men. A follow-up study by the same group showed that redheaded men and women (and mutant "redhead" mice) had a greater analgesic reponse to morphine-6-glucuronide.
Red Heads and Kwashiorkor condition
In cases of severe malnutrition, normally dark human hair may turn red or blonde. The condition, part of a syndrome known as kwashiorkor, is a sign of critical starvation caused chiefly by protein deficiency, and is common during periods of famine.Red Heads in Culture
A red-haired woman, Far Away Thoughts John William Godward 1892. Red hair was a popular subject amongst Pre-Raphaelite artistsIn various times and cultures, red hair has been prized, feared, and ridiculed.Queen Elizabeth I of England was a redhead, and during the Elizabethan era in England, red hair was fashionable. This was also the case during the rule of redhead Oliver Cromwell. In modern times, red hair is subject to fashion trends; celebrities such as Rita Hayworth or Gillian Anderson can boost sales of red hair dye.
Often, ginger hair darkens as people get older, becoming a more brownish colour or losing some of its vividness. This leads some to associate red hair with youthfulness, a quality that is generally considered desirable. In several Muslim countries such as Iran and Pakistan, henna is used on greying hair to give it a bright red appearance.
Red hair can also be subject to ribbing and ridicule. In the Middle Ages red hair was disparagingly called judas-colored, in reference to Judas Iscariot. In modern-day UK and Ireland, the word "ginger" (often pronounced to rhyme with 'ringer' (as opposed to or "ginger minger" is derogatorily used to describe red headed people. Redheads are also sometimes referred to as "carrot tops." This "gingerphobia" has been satirised on a number of TV shows. The British comedienne Catherine Tate appeared in a running sketch in an episode of The Catherine Tate Show in which she was forced to seek solace in a refuge for ginger people; the pejorative use of the word "ginger", and related discrimination, was used to illustrate a point about racism and prejudice in the "Ginger Kids" episode of South Park; and the British comedy Bo' Selecta! featured a spoof documentary which involved a caricature of red-haired "Simply Red" singer Mick Hucknall presenting a show in which celebrities (played by themselves) dyed their hair ginger for a day and went about daily life being insulted by people.
A common stereotype of redheads is that they have fiery tempers. Another is that they are highly-sexed; for example, Jonathan Swift writes: "It is observed that the red-haired of both sexes are more libidinous and mischievous than the rest." Witches are frequently portrayed as redheads.
Many painters have exhibited a fascination with red hair. The colour "titian" takes its name from Titian, who often painted women with red hair. Other painters notable for their redheads include the Pre-Raphaelites, Edmund Leighton, Modigliani , Gustav Klimt and Sandro Botticelli, whose famous painting, The Birth of Venus, depicts the mythological goddess, Venus, as a redhead.
