Sunday, May 5, 2024

BBC Radio 4 Ingenious, The Ginger Gene

where does red hair come from

However, a majority of the pheomelanin-rich population live in the northern hemisphere, where the sun is not as harsh as in the equatorial region. Because the population does not face the wrath of the burning rays of the sun, their body doesn’t require a large amount of eumelanin pigment. When the MC1R gene is activated, the cell will have more MC1 receptors, which will cause your melanocytes to produce more eumelanin and give you a darker hair  color. Now researchers at the University of Edinburgh have looked at DNA from almost 350,000 people who had taken part in the UK Biobank study. The study, which was led by The Roslin Institute and the MRC Human Genetics Unit, focused on people of European descent because they have greater variation in hair colour.

Does Norway have a lot of redheads today?

The study – which also sheds light on blondes and brunettes – is the largest genetic study of hair colour to date. Blue eye colour is a recessive trait, which means both parents must carry the gene for the child to be born with it. As previously mentioned, ginger hair occurs naturally in an average of just two percent of the world’s population, while only 17 percent of humans have blue eyes.

Prejudice and discrimination against redheads

This fact not only rules out interbreeding as a route for Homo sapiens red hair, but it also rules out early Europe, as it’s the birthplace. You can, of course, see whether there is anyone with red hair in your family. However, even if this has not been the case for generations, it is still possible that you carry a (recessively inherited) red-hair gene. There are theories that the pale skin with which red hair is often paired was favourable from an evolutionary point of view in less sunny areas. This is because pale skin still produces sufficient vitamin D when there is little sunlight.

where does red hair come from

How does hair color work?

According to historical records, there are more redheads in the Volga region in Russia than anywhere else in the world. The men around this region have been described to have the most red hair in the rest of the world. All of these red-haired tribes match the genetic makeup of the current inhabitants of the lands they occupied. Scotland, Wales and Ireland respectively- the British Celtic nations- all having the high level of red gene carriers and manifestations. On mainland Europe, Brittany, the border between France and Belgium, Switzerland, and Jutland – the ancestral lands of the Gaulish and Germanic tribes- also carry high levels of the red-haired gene.

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Scientists believe that the distinct gene mutation is more common in climates where there is little to no harmful sun exposure. Red hair is a recessive genetic trait caused by a series of mutations in the melanocortin 1 receptor (MC1R), a gene located on chromosome 16. As a recessive trait it must be inherited from both parents to cause the hair to become red. Consequently there are far more people carrying the mutation for red hair than people actually having red hair. In Scotland, approximately 13% of the population are redheads, although 40% carry at least one mutation.

From the assumptions about Norsemen having beards, you can assume that the ones who lived in areas where you find red hair genes dominant would, consequently, have had red beards. From 27 to 29 August redheads from around the world will be gathering again in Tilburg for Redhead Days, an annual international event that celebrates red hair. And can you pass red hair on to your children even if you do not have red hair yourself?

The Mysterious History of Red Hair

On Life As A Freckle-Faced, Redheaded, Mexican American From Southeast Los Angeles - LAist

On Life As A Freckle-Faced, Redheaded, Mexican American From Southeast Los Angeles.

Posted: Fri, 26 Jun 2020 07:00:00 GMT [source]

The MC1R gene found on chromosome 16 plays a critical role in the process of melanin synthesis by melanocytes. The MC1R gene provides instruction for the formation of a protein known as the melanocortin 1 receptor, which are present on the surface of melanocytes. Even as far back as Neolithic times, the 45th parallel roughly divided the Mediterranean Cardium Pottery culture from the Central European Linear Pottery culture. Superstar actress Nicole Kidman is perhaps Australia’s best known redhead, while British model Alexina Graham became the first ever ginger beauty to walk the Victoria’s Secret Fashion Show in 2018. Sir Arthur Conan Doyle's Sherlock Holmes story "The Red-Headed League" (1891) involves a man who is asked to become a member of a mysterious group of red-headed people.

Once again, they regarded redheads, as untrustworthy- yet red hair was also desirable, as many Roman ladies aspired to it, prompting Roman wig makers to import quantities of red hair from northern Europe. “Hence, too, the same physical peculiarities throughout so vast a population. While redheads are born all throughout the world, they’re more likely to crop up in the Northern hemisphere. Though about 1-2% of the general world population has the red hair gene, that percentage rises to 2 to 6 percent north of the equator. You might believe that because these genetic traits are rare, they could be diluted out of the gene pool entirely.

where does red hair come from

There are more than seventy known variants of the MC1R gene that can influence your hair colour. This means that you will only get a red hair colour if two ‘alleles’ of the gene are present that suppress eumelanin production. It is therefore possible for two people, neither of whom has red hair but who both carry this gene, to unexpectedly have a child with red hair.

What is immediately apparent to genetic genealogists is that the map of red hair correlates with the frequency of haplogroup R1b in northern and western Europe. It doesn't really correlate with the percentage of R1b in southern Europe, for the simple reason that red hair is more visible among people carrying various other genes involved in light skin and hair pigmentation. Mediterranean people have considerably darker pigmentations (higher eumelanin), especially as far as hair is considered, giving the red hair alleles little opportunity to express themselves. The reddish tinge is always concealed by black hair, and rarely visible in dark brown hair. Rufosity being recessive, it can easily stay hidden if the alleles are too dispersed in the gene pool, and that the chances of both parents carrying an allele becomes too low.

The thing is, there were already red haired individuals way before the Vikings era. Scientific evidence points towards red haired people around the period that Celtic and Germanic tribes thrived. One can argue that the genetic disposition for red hair was already among the population. The Classical suspicion of redheads probably derived from the fact red hair was so rare in the Mediterranean regions.

23andMe’s Health + Ancestry Service can tell you more about the genetic roots of your hair color. People who have certain variants in this gene are more likely to have red hair because they have higher levels of pheomelanin. The Italic branch crossed the Alps around 1300 BCE and settled across most of the peninsula, but especially in Central Italy (Umbrians, Latins, Oscans). It is likely that the original Italics had just as much red hair as the Celts and Germans, but lost them progressively as they intermarried with their dark-haired neighbours, like the Etruscans. The subsequent Gaulish Celtic settlements in northern Italy increased the rufosity in areas that had priorly been non-Indo-European (Ligurian, Etruscan, Rhaetic) and therefore dark-haired.

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BBC Radio 4 Ingenious, The Ginger Gene

Table Of Content Does Norway have a lot of redheads today? Prejudice and discrimination against redheads How does hair color work? Get Mum...