The INSIDER Summary:
• Some people have red beard hair, but not red head hair.
• It’s because of a mutation in a chromosome involved in producing hair pigment.
• Don’t worry, it’s not dangerous.
While only a small percentage of people in the world are redheads, non-redheads can still grow red beards.
That’s because of a curious genetic quirk that makes it possible for people to grow red hair in the first place.
Hair colour is determined genetically, and can be inherited through different genes from parents, grandparents, and ancestors that reach even further back. That increases the wide range of hair colours and colour combinations that can be expressed on a person’s body.
The precise shade of the colour is determined by the amount of melanin — a type of organically developed pigment — in your hair. The type and amount of melanin is determined genetically.
“For white people the shades are dependent on two sorts of melanin: eumelanine (black pigment) and pheomelanine (red pigment),” Petra Haak-Bloem, a specialist at the Dutch national genetic research center Erfocentrum, told Motherboard. “Hair cells of dark haired people only contain eumelanine. Blondes have less eumelanine. And redheads’ hair contains mostly pheomelanine.”
Having a red beard and non-red head hair is linked to a mutation on the MC1R gene, which appears on chromosome 16 in the DNA sequence.
MC1R plays an important role in making a protein involved in the production of the melanin that determines red hair.
People inherit two different types of MC1R, one from each parent, Haak-Bloem explained to Motherboard. So if one of those MC1R genes is mutated, you end up with people who have red hair in one place but not the other, because the two different types of MC1R are producing hair colour pigments in different ways.
That means you can end up with red beard hair and brown regular hair, like some people do. It’s one mutated MC1R gene expressing itself in one part of the body. A similar genetic principle explains why hair texture is different on different parts of the body.
But if that’s the case, why is it that it’s relatively common to have dark hair and a red beard, but not red hair and a dark beard? And why doesn’t this happen with other colour combinations?
Haak-Bloem said he wasn’t sure. As far as genetic research goes, having a red beard isn’t linked to any deadly diseases, so it hasn’t been researched very much.
So if you have a copper-coloured beard that doesn’t match your head hair colour, don’t worry — you’re definitely not alone.
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