Redheads are a rare breed, with ginger hair accounting for less than 2% of the global population. With such low numbers, would it be possible for red hair to go “extinct”, leaving people with natural hair ranging from black to blonde with no hint of red?
In a word, no. Experts told Live Science how red hair genetics mean the trait is sticking around.
“There is no evidence that redheads are becoming extinct,” he said Katerina Zorina-Lichtenwalteris a research associate at the University of Colorado Boulder’s Institute for Behavioral Genetics studied the inheritance of red hair. He told Live Science that the genes responsible for red hair “are harmless, they do not interfere with reproduction and they are not linked to any diseases that could prevent people from reaching reproductive age.”
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Still, the myth of impending red hair extinction is not new.
“‘Are redheads going extinct?’ This question has remained for decades,” ian jacksonProfessor Emeritus of the Institute of Genetics and Cancer at the University of Edinburgh told Live Science. “There are also stories of blonde hair becoming extinct that go back to the mid-19th century.”
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The reasoning behind alleged redhead extinction usually goes something like this: Red hair is rare; In Redhead Hotspots of the World In the United Kingdom and Ireland, only 10% of the population is classified as redheads. And red hair is a recessive trait, meaning that two red hair carriers must mate together to produce a red-haired child.
There’s even questions about whether potentially fatal conditions, such as melanoma, could plague redheads, who are especially sensitive to sunburn. While people of color are with red hair (Malcolm had red hair), red hair is often Linked to pale skin and hence, increased risk of skin-cancer. Redheads’ higher melanoma risk isn’t just because they burn more easily. This is also due to Harmful chemicals from pheomelaninthe pigment that helps create the red color of hair, and low DNA-repair protectionWhich is linked to different variants of the gene that cause red hair.
keeping the flame alive
But experts say these issues won’t drive redheads to extinction.
First, let’s look at genetics. A person needs to get the ineffective version of mc1r – A gene involved in pigment production – from both parents. Someone with only one copy may not have red hair at all, but they can still pass the type on to their children. Therefore, the role of carrying the red hair gene across generations is shared by people of all hair colors, not just those with red hair.
Redheads celebrate Redhead Day in the city of Breda, Netherlands, on September 4, 2016.
(Image credit: Brian Dowling via Getty Images)
This hidden-carrier effect is why a recessive trait can persist in a population even when it is unusual to see it. Jackson gave a simple example: If half the population has one type of infection, only about a quarter of the couples will carry it. Of those couples, about one-quarter of children will inherit two copies.
For red hair to truly disappear, the associated variants would have to be continually removed from the gene pool. In evolutionary terms, this would usually mean that people with these variants – or people with red hair – were having fewer children than everyone else.
“The only reason things go extinct in large populations is because you don’t have as many children as others, simply put, and I don’t know that there’s any evidence for that,” jonathan reesemeritus professor of dermatology at the University of Edinburgh told Live Science.
Second, let’s look at the risk of skin cancer. Rees said people with the MC1R variant have a much higher risk of skin cancer two to four times“
But skin cancer risk does not automatically equate to evolutionary decline. Many skin cancers occur after people have already had children. Death rates from melanoma in the UK are highest among people aged 90 and over, According to Cancer Research UKWhen they have had more than enough time to pass on their genes.
Theoretically, before the invention of sunscreen and modern medicine, redheads may have been more likely to die from skin cancer before having children. However, given that this trait is persistent, are there any evolutionary benefits to having red hair?
Red hair can bring amazing health benefits. For example, recent research Suggested that the red-hair pigment pheomelanin may help regulate excess cellular cysteine, which can be harmful in high concentrations.
“The vitamin D story is one that people talk about most often,” Rees said. The idea is that light pigmentation of the skin (and red hair being associated with light skin) Vitamin D levels increase in people during the gloomy winter. But he said the evidence is lacking, particularly because it can be difficult to define who actually is a redhead. It’s a spectrum: Where does red hair end and strawberry blonde hair begin? This makes it difficult to study without sequencing the genome of a large portion of the population.
However, the frequency of red hair may still fluctuate. Jackson said the frequency “may decline somewhat as people become more mobile” and have children with partners from areas where MC1R variants are less common. But that would be a change in frequency, not extinction.
As long as the MC1R variant remains quietly present in carriers — and as long as redheads don’t have significantly fewer children than everyone else — the redheads of the world are not going to disappear.
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