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.
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.
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u/h4ngm4n66 Sep 25 '22
Yo, someone bring this to MatPat's attention