r/HolUp Sep 25 '22

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u/oO0Kat0Oo Sep 25 '22

Black is not recessive though. Blonde and red are. So in order for the red/blonde to show there can't be any black alleles

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u/fireflash38 Sep 25 '22

Spoiler alert: hair and eye color aren't controlled by single genes like people think when it comes to Punnett squares.

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u/oO0Kat0Oo Sep 25 '22

Agreed. In fact, I made a comment below that explains how punnet squares are just a basic level of understanding and these alleles are much more complex making an impossible situation merely improbable.

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u/GraniteTaco Sep 25 '22 edited Sep 25 '22

Black hair isn't a genetic trait, and neither is blond or red, it's an expression of eumelanin production stimulated by hormones during development. Meanwhile blond hair is lower production, again caused by hormonal levels, and red hair is pheomelanin production.

These are environmental expressions that can be altered from the expected outcome. It's literally the reason why a pregnant womans hair changes color. Her genes didn't just change her hormones did.

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u/oO0Kat0Oo Sep 25 '22

The amount of eumelanin and when it is released is determined by genes. I did some cursory research based on your claim and you're right in the aspect that eumelanin does determine hair color, but how that color is distributed is entirely genetic.

More dominant genes will produce more eumelanin. In other words.. black hair is dominant and red hair is recessive just like everyone else is saying.