“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
Say B is dominant brunette, and b is recessive blonde. If we start with a population that is 50-50 BB and bb, so half the population is brunette and half is blonde. Everyone couples up with the opposite color and we now have the next generation being 100% Bb, so everyone is brunette. The generation after that will be 25% BB, 25% bb, and 50% Bb. We now have 75% brunettes and 25% blondes. Even though blondes were “extinct” for a generation, they came back because their genes were always alive. If we look at the gene distribution: 25% BB, 25% bb, and 50% Bb. We see that it’s still 50-50 B and b just as the original population. The only way blondes get extinct is if they are seen as unfavorable, and don’t get as many partners.
Latest Answers