I pretty much know jack about genetics but thought a kind Doper might help explain this. I do remember Pundit squares but it was so long ago I think many things have changed or are clearer.
To get an idea of my question I’ll need to explain. My heritage is western European. Name a country and it’s in there. Throw in some Polish, too for good measure. Mutt, thy name is BBJ. However I LOOK like I am paying tribute to a Norwegian ancestor. Blonde hair (dishwater now but white for years), translucent white skin (see my veins type) and slightly uptilted bluegreen eyes.
My understanding is these are all recessive type genes, but I know it’s not just one gene per trait although this was not what they used to teach. I have 2 kids from a pasty, blue eyed, light brown haired (blond as kid) Scottsman. Not surprisingly the kiddos are white haired, blue eyed, and pasty skinned with a slight tilt to their eyes.
The question is since I think I have a ton of recessive genes, if I keep spawning with like recessives is there a possibility my outwardly missing genes show up and I’ll get a brown eyed kiddo that has the ability to tan or even a red haired kiddo, or one with Welsh dark hair and skin? Or is my only hope for something to change is use a male with stronger genes to beat mine into submission? Are those ancestral characteristics in me just waiting to jump out or are they now inoperative or missing so I’ll need to steal anything different from a male with those other outwardly expressed genes?
My present spouse cannot have children and we are looking at artificial insemination. Spouse has brown hair and brown eyes, and I will have a brown eyed, tannable child damnit! I want him to feel that this is his child as much as he can both physically and emotionally. I worry if I find a clone donator it still might not help.
Sorry if I sound like an idiot. Haven’t brought it up to the doc yet. Help me sound less stupid please!
To clarify my hope of a rogue gene popping up that will be different, the father of first 2 offered semen, but although we’ll have 3 full siblings I don’t think it’s likely that the child will look anything different than the first 2.
Almost certainly no. If you (for example) have blond hair you just don’t possess a gene for brown to pass on to an offspring. It’s not hidden somewhere, you just don’t have it. If you mate with another blond the two of you just don’t have dark hair genes to pass on. Ditto for skin color.
Green eyes are a little different… I’m not entirely clear on those, but I think it’s possible for two green-eyed people to have a brown eye child, but don’t quote me on that.
If the biological father is carrying a recessive gene for, say, blond hair then you have a 50/50 chance of a blond child rather than a brunette child for any given pregnancy. There is no way to tell by just looking if he has two brown-hair genes or 1 brown and 1 blond. If you can select a sperm donor from a family that is exclusively dark-hair and dark-eyed for as far back as anyone knows the odds of the being double-dominant are higher but it’s sort of impossible to guarantee someone of European ancestry has no genes for blond hair or blue eyes.
Sorry if I sound like an idiot. Haven’t brought it up to the doc yet. Help me sound less stupid please!
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Blue eyes in humans is a full recessive. If both parents have blue eyes, then all their children will have blue eyes (barring a mutation).
Blue-green eyes, such as you say you have, are probably just a variant of blue. Full green eyes are dominant to blue, but recessive to brown. Since your kids have blue eyes, this indicates you do not have the green allele. (If you did, they would have green eyes.)
People with brown eyes can have either two copies of the brown allele, or one each of brown and blue (or green). Without expensive testing, I don’t think there is any easy way to distinguish between these alternative. Pairing with a blue eyed person, someone with two brown alleles will produce entirely brown-eyed children. One with one brown and one blue has 50-50 odds of producing a blue-eyed child with a blue-eyed partner. Two brown eyed individuals who are both brown/blue have 75% odds of producing a brown eyed child, and 25% of producing a blue eyed one.
Hair and skin color is much more complex. For hair, brown is dominant over blond, and red is recessive to other colors. However, there are many other factors that affect the exact color shade of hair. Two blond individuals will almost always have blond children. However, brown haired individuals can produce blond children according to the same principles as for brown/blue eyes. For skin color, there are probably even more genes involved.
I don’t follow… If BBJ had one blue allele and one green allele, then she’d have green eyes, possibly slightly blue if the dominance isn’t complete, which is consistent with her description of blue-green eyes. Her children could by chance have both inherited the blue allele from her and not the green one, and if they also get blue-eyed genes from their dad, they’d have blue eyes. How does them having blue eyes prove that BBJ doesn’t have a green allele?
In summary (Table 4) blue-eyed people have an A to G mutation in the promoter region of a gene for melanin production (OCA2), and everyone with blue eyes shares a common ancestor from 6-10k years ago.
So, if you have enough children, it is possible one will have reversed this mutation and turn the promoter back on at this specific spot. Children have between 0 and 300 nucleotide changes from their parents, depending on the source. Your genome is 3 billion base pairs. So doing very fast and probably incorrect math, it’s about a 1 in 10 million chance that your child would gain this specific mutation.
The origin and inheritance of green eye color is actually incompletely known, and I cannot claim to be an expert. However, to the best of my knowledge the situation is this:
There are two separate genes at different loci. Gene 1 has two alleles, brown (B) and blue (b). Gene 2 has two alleles, blue (b) and green (G).
If you have even one B gene, you have brown eyes regardless of which allele you have at Gene 2. If you are bb for Gene 1, then you can have either blue or green eyes. If you have even one G allele at Gene 2 you have green eyes; if you are bb you have blue eyes.
As I said above, as far as I know bluish-green eyes are just a variant of blue; they are caused by some other genetic factor, not the influence of the G allele. To the best of my knowledge G is a simple dominant, and if you have it your eyes will be green. (I could be wrong on this.) Therefore if BBJ has bluish green eyes (rather than fully green ones) she is probably bb bb, and doesn’t have a G allele.
Of course, since I don’t know BBJ’s exact eye color, it’s possible that she actually does have true green eyes, in which case she must be bb Gb.
Here’s more on the inheritance of brown/blue/green eyes.
Sure, but that’s still not consistent with "Since your kids have blue eyes, this indicates you do not have the green allele. (If you did, they would have green eyes.) ". The fact that BBJ has bluish eyes might be evidence that she doesn’t have the green allele, but the fact that her kids have blue eyes is not evidence for that.
Let’s not forget that what we have learned from the human genome project completely screws up classic mendelian genetics. We thought we had upwards of 100 thousand genes. Turns out we have about 20 thousand - the same number as a freaking round worm. We are currently rethinking our definition of “gene”. Operators and promoters don’t mean nearly as much as what we once thought, and it turns out that most of the proteins that make us, well, us use a blueprint from several different places on our DNA.
In short, there is no good answer to BottledBlondJeanie’s O.P.
I made a mess of that, didn’t I. What I was trying to convey was that BBJ did not have a green gene “hiding” somewhere, that could be expressed in her kids if it was not present in her. You are correct.
Getting back to the OP, speaking generally, if you’re expressing recessive genes - that is, people can see that you have those genes when they look at you - then you don’t have any other “hidden” genes hanging out somewhere. It’s the reverse. If you were expressing dominant genes, then you could have some recessive genes (well, alleles, but let’s keep it simple) hiding, waiting to be expressed. That’s what dominant and recessive mean. So, if we accept as given that you and your partner both express the recessive versions of the traits you’re talking about - skin color, eye color, etc - then, no, there’s no chance for you to have a vastly different-looking child together. You’d need a partner with some dominant genes to overrule your own.
Now, as has been made clear here, it’s more complicated than that. But that’s the general idea, which seems to be what you’re after.
I had a brown eyed child and we both had hazel eyes. I have a brother with one blue eye and one that is half blue and half brown. My parents were blue and hazel eyed. My family is recessive also and Irish and all have blue or hazel eyes.
Make sure your donor has Brown eyes and you should be all set.
What I was trying to convey was that BBJ did not have a green gene “hiding” somewhere, that could be expressed in her kids if it was not present in her. You are correct.