The Disappearing Blond Gene (hoax)


“The disappearing blonde gene was a hoax claiming a scientific study had estimated that natural blonds would become extinct, repeated as fact in reputable media such as the BBC and *The Sunday Times* between 2002 and 2006.”

“The hoax claimed that, because the allele for the genes for hair colour is recessive, blond hair would become less common as people with dominant non-blond hair alleles had offspring with people with the recessive alleles, even though such a pairing would retain one copy of the blond allele in the genome of the offspring. Claims that blond hair would disappear have been made since 1865.”

I’m trying to understand *why* it’s a hoax *and* how *the reality* works. To a layman and uneducated non-expert on genes, like myself, the premise of the hoax may at least *seem* logical:

If more and more people with the **dominant blond-hair gene** have offspring with people that have a **dominant non-blond gene**, then, eventually, the blond-hair gene may still *exist* but blond-haired people will be a rarity, because the blond-hair gene will be dominated by dominant non-blond genes. I mean, wouldn’t a traditional blond-haired, blue-eyed Swede only be born through two people with the dominant blond-gene?

In: 16

If my I understanding’s of genes is correct recessive genes are just as likely to be passed on as dominant genes so there’s no real reason they would go extinct

The premise is logical in itself the issue is the general time frame, there are currently millions of people with the gene meaning that no matter what else 50% of their offspring will carry the gene even if the other parent doesn’t carry the gene. So we are talking thousands of generations for the gene to disappear without people preferring the gene and having relationships accordingly.

Because thats now how recessive genes work. As long as genes are presented, there will be people with blonde hair. Unless you specifically remove all people who has blond gene in them you will get blonde people.

There is no such thing as a dominant blond gene, at least not in humans. Blond hair is always recessive trait, whether in Sweden or Algeria.

Thing is, though, recessive genes don’t simply disappear forever. If genetics worked that way, recessive genetic disorders like Tay-Sachs and cystic fibrosis would have disappeared long ago.

In terms of hair colors, it’s possible for a brunette and a blond to have a blond child if the brunette parent happens to have blond genes, which they might have as a result of having a blond ancestor at some point.

It’s also possible for two people with black or brown hair to have a blond child if they both happen to have the recessive blond genes. I believe the odds of this happening are about 25%, which isn’t high, but it’s still a long way from never.

I don’t know anything about hair genes but….
if blond is simple recessive it means lots of people with brown hair have some blond genes.
Recessive means the brown wins, the hair is brown and nobody knows the blond genes are hidden in them.
Two of those brown with blond genes people will have about 1/4 blond children.
Hair color in humans is probably more complex but this is the ELI5 version.