Not a geneticist, but after some googling, here's what I found:
Red hair is caused when a person's body makes pheomelanin (red pigment) and can't convert it into brown pigment (eumelanin). This is usually due to a lack of a protein called MC1R, which is created by a gene conveniently also called MC1R.
Blondes can have one working copy of this gene (M) and one non-working copy (m). Let's assume Bob has one of each of these genes (Mm).
Usually, redheads have two non-working copies of this gene (mm), one from each parent. If Helene's genes look like this, then Violet should have red or blonde hair, depending on what version of the gene she got from Bob.
However, if Helene had the R160W mutation of the MC1R gene, she could have one working copy and one non-working copy (Mm) but the mutation would cause the proteins they create to interfere with each other. She could potentially pass on the working copy to Violet, which combined with Bob's working copy, would give her dark hair.
But wouldn't that make Dash a redhead? Not if he got Helene's working MC1R and Bob's non-working MC1R (Mm). Then he'd be blond like his dad.
EDIT: References:
McDonald, J.H. , 2011. Myths of Human Genetics [Online]. Baltimore: Sparky House Publishing, pp. 37-39. Available from: https://udel.edu/~mcdonald/mythredhair.html [Accessed 25 Jun 2020]
Starr, B., 2010. Stanford @ The Tech: Understanding Genetics: Other Traits [Online]. San Jose: The Tech Interactive. Available from: https://genetics.thetech.org/ask/ask343 [Accessed 25 Jun 2020].
code_monkee on June 25th, 2020 at 18:00 UTC »
All y'all trying to apply genetics to a damn superhero cartoon.
When clearly the color of her hair is a result of the light refraction from the energy field that envelopes her.
ocular-pat-down on June 25th, 2020 at 18:03 UTC »
We all know she's emo and begged for the $4 box of black dye and went invisible until they got it for her.
Lexotron on June 25th, 2020 at 18:23 UTC »
Not a geneticist, but after some googling, here's what I found:
Red hair is caused when a person's body makes pheomelanin (red pigment) and can't convert it into brown pigment (eumelanin). This is usually due to a lack of a protein called MC1R, which is created by a gene conveniently also called MC1R.
Blondes can have one working copy of this gene (M) and one non-working copy (m). Let's assume Bob has one of each of these genes (Mm).
Usually, redheads have two non-working copies of this gene (mm), one from each parent. If Helene's genes look like this, then Violet should have red or blonde hair, depending on what version of the gene she got from Bob.
However, if Helene had the R160W mutation of the MC1R gene, she could have one working copy and one non-working copy (Mm) but the mutation would cause the proteins they create to interfere with each other. She could potentially pass on the working copy to Violet, which combined with Bob's working copy, would give her dark hair.
But wouldn't that make Dash a redhead? Not if he got Helene's working MC1R and Bob's non-working MC1R (Mm). Then he'd be blond like his dad.
EDIT: References:
McDonald, J.H. , 2011. Myths of Human Genetics [Online]. Baltimore: Sparky House Publishing, pp. 37-39. Available from: https://udel.edu/~mcdonald/mythredhair.html [Accessed 25 Jun 2020]
Pennisi, E., 2014. The Genetics of Blond Hair [Online]. Washington: Science. Available from: https://www.sciencemag.org/news/2014/06/genetics-blond-hair [Accessed 25 Jun 2020]
Starr, B., 2010. Stanford @ The Tech: Understanding Genetics: Other Traits [Online]. San Jose: The Tech Interactive. Available from: https://genetics.thetech.org/ask/ask343 [Accessed 25 Jun 2020].