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Scientifically Speaking...

koehlerrock

Parents that have blue eyes, (that is both of them) can't have a child with brown eyes.
Make a story with said logic, whether crime doing wanna be parents or adoption, it would be pretty neat.

Ernest Bywater

@koehlerrock

Parents that have blue eyes, (that is both of them) can't have a child with brown eyes.


check the genetic rules on a throwback (atavism) and dominance I'm not sure you can say it's impossible or not. That's something you'd need to check with a geneticist for a definitive answer.

https://en.wikipedia.org/wiki/Atavism

https://en.wikipedia.org/wiki/Dominance_(genetics)

Crumbly Writer
Updated:

@koehlerrock


Parents that have blue eyes, (that is both of them) can't have a child with brown eyes.

Make a story with said logic, whether crime doing wanna be parents or adoption, it would be pretty neat.


Both parents, both eyes or all four eyes? But either way, I'm not sure that's true. Blue eyes are, I believe, merely a recessive gene. The problem is, for most non-Europeans, you've got hundreds of generations with brown eyes, so there aren't as many available blue-eye genes. However, I've seen photos of the occasional blue-eyed Asian, though only a couple. If child of brown eyed parents could ever have blue eyes, the blue-eyed gene would eventually be eliminated (at least in it's expressed form). Instead, it's merely statistically unlikely.

But beyond that, it would be difficult building a plot around such a detail, or even a minor plot or individual character element beyond a "Oh, wow, you've got blue eyes?" moment. Maybe in the crime story, they decide to steal a set of blue eyes?

tppm

@koehlerrock

Parents that have blue eyes, (that is both of them) can't have a child with brown eyes.
Make a story with said logic, whether crime doing wanna be parents or adoption, it would be pretty neat.


Everyone else in my family has blue eyes, mine are hazel.

Not_a_ID

@koehlerrock

Parents that have blue eyes, (that is both of them) can't have a child with brown eyes.
Make a story with said logic, whether crime doing wanna be parents or adoption, it would be pretty neat.


Supposed to be the same story for Green or even Grey eyes from my understanding. They're "recessive traits," thus requiring both parents to posses(and pass along) that genetic trait in order to pass it along to their children. (And working out the dominance between them can be fun, although simplified charts will give you Brown(dominant) vs Blue(recessive), and then Green(dominant) vs Blue(recessive) genetic pairings(So someone like me with Green Eyes needs to have the Blue Eyed genes in place of the Brown ones, and I can then be either GG or Gb on the second set)

That being said, genetics isn't quite that simple, and as already mentioned, even normally dominate traits can sometimes skip generations. As such, it isn't impossible for such a thing to happen, it simply is unlikely to occur. Further complicating it is some traits(like eye color) aren't fully decided by just one "pairing" of genes (one of the links below says current studies suggest up to 16 different pairings being involved), so there are other ways for eye color to turn up unexpected results in cases of parents with a rare/recessive eye color.

For a very simplified version(that somewhat concurs with the OP, but only because it is simplified)
http://genetics.thetech.org/ask/ask59

For more depth:
http://www.allaboutvision.com/conditions/eye-color-chart.htm

http://www.allaboutvision.com/conditions/eye-color-hazel.htm

Although this one seems to go into a little more depth.

http://sandwalk.blogspot.com/2007/02/genetics-of-eye-color.html

The "funky one" in the bunch seems to be the Green Eye allele in the mix. From what I'm seeing, it can express itself as anything from Brown to Hazel(the second most common "expression"), to Green(which is more typical, hence it being tagged as such), to even being Blue or lighter(grey). So... That "Blue Eyed parent" may actually have green eyes that have expressed themselves as Blue eyes. Which may result in their pairing with another "blue eyed parent" and coming out with a "green eyed child" who expresses that genetic gift with brown or hazel eyes instead.

Which I guess explains how actual honest to god Green Eyes is reportedly more rare than having Blue Eyes even though it is the dominant trait between the two. As the "green eyes" trait is probably recessive to yet other traits that the "blue eyes" trait is not.

richardshagrin

As Mr. Wong said to Mrs. Wong, in the maternity ward after she gave birth, when presented with a white baby, two Wongs don't make a white.

Replies:   Not_a_ID
koehlerrock

I regret this idea, all y'all science geeks are making me nauseous

Not_a_ID

@richardshagrin

As Mr. Wong said to Mrs. Wong, in the maternity ward after she gave birth, when presented with a white baby, two Wongs don't make a white.


Unless Mrs. Wong was White to start with, and Mr. Wong himself had at least one white parent. (Adoption is an option)

Not_a_ID
Updated:

To make things more frustrating, I have found more resources referencing the 16 different pairs of genes being involved in eye color. (Not to be confused with 16 possible pairings)

But I've also seen some other (.edu) stuff reiterating the 2 pairs of genes being involved. Only it described the first as Brown/blue and the second as Green/hazel with brown being dominant over everything, Green dominant over hazel and blue, but hazel dominant over blue to some degree. bb/GG gives Green eyes, bb/Gg gives hazel, bb/gg gives blue under that pattern, all other results return as brown eyes.

But in terms of melanin content in the eye, it pretty much seems consensus is two gene pairs are primarily involved. Blue eyes have the least(and why many babies have blue eyes at birth that turn to other colors as they age and reach their genetic "set point" for melanin) while brown eyes have the most.

Complicating factors are the other structures within the eye and even the shape of the eye itself, which can change the refractivity and reflectivity of light once it enters the eye. (In reality, there is no blue or green pigment in the human iris, the only coloring comes from melanin(which is brown, and why it's so dominant as a trait), and blood flow(rarely), everything else is optical illusion)

Which is where those other genes come into play, and can make a mess of things. In particular for those people whose eye color seemingly changes based on lighting conditions/what they're wearing.

There also are a evidently a few other genes tied to melanin production in general(body wide) which can also influence eye coloring, but they're very rarely decisive as to the brown/green/blue/hazel/grey/violet thing, they'd be more likely to impact the shade of the relevant color that results.

Crumbly Writer

A caveat to the above material: "hazel" eyes are, by definition, a variety of different colors. It worked out while I was dating, as my eyes would often match whatever the girl I was dating was wearing.

On the other hand, to further complicate things, there are many instances of people with two different eye colors: likely the result of more than two genes (ex: such as XYX) which isn't apparent otherwise.

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