Why dont i have blue eyes? Genetics?

Question

My mom has blue-grey eyes, her mom has blue eyes, and her dad had green eyes.

My dad on the other hand has dark brown eyes, his mom has hazel green eyes, and his dad has dark brown eyes.

My question is why did i come out with light brown eyes but not blue eyes or green eyes?

Answer 1

Brown is dominant over blue.

I'm not saying it's impossible for you to have been born with blue, it isn't.

It is just more likely that if a blue-eyed person and a brown-eyed person have a child, that the child will have brown eyes.

Answer 2

You came out with brown eyes because the gene for brown eyes is dominant.  Based on your father's family history, it seems that he is homozygous brown eyes (mostly, you can't really split hairs with hazel eyes), and your mother has blue eyes as you had stated.  When homozygous blue and homozygous brown color for eyes appears, the chance that you would have blue eyes is absolutely 0%.  Your dad's gene will win every time, since blue eyes are recessive.

As for having green eyes, your dad has green eyes due to a combination of blue eyes and brown eyes with his parents that resulted in non-dominance, or a combination of the two (much like in red and white mixing to make pink).

Sincerely,

R.T.K.

Answer 3

Brown is a dominant color over blue.  also, genetically, green codes out to brown.  If you look into a person's green eyes, you can actually see some brown areas.

Answer 4

Eye color is a very odd thing. It doesn't work based so much on dominance and recessiveness as it does with the amount of pigments. So, for example, certain genes have a lot of pigments, which make shades of brown, and certain genes have lighter pigments, which make blue. This would make sense for you, because this way you have a mixture of your father (who has dark brown and a lot of pigments) and your mother (who is blue-grey with little pigment) to make light brown, which is somewhere in between.

Answer 5

Brown eye is dominant. Your father is heterogeneous for brown eyes, and so are you.

Answer 6

Brown dominant gene. Each parent carries a set of genetic markers (2) and in development one marker is taken from each parent to make up your 2. I there is at least 1 dominant gene then that is what your eye color will be regardless what the other is. It is possible for you to get blue eyes from your parents if you father carries a recessive gene. Example

B=Brown eye gene

b=Blue eye gene

Father has Bb (since the B brown eye gene is there he has brown)

Mother has bb (she has blue since there are no other markers)

The possible combination of markers from your parents are:

Bb = Brown eyes

Bb = Brown eyes

bb = Blue eyes

bb = Blue eyes

So you would have a 50/50 chance to have Blue or Brown eyes.

If your father has 2 dominant genes (BB) then there is no chance for you to get blue.

Combos:

Bb = Brown

Bb = Brown

Bb = Brown

Bb = Brown

Answer 7

Brown is dominant, so it can override  blue. That means, you need the blue gene from BOTH parents to have blue eyes.

Your mom only has the genes for blue, since she has blue eyes. You carry one of those genes.

Your dad probably has one gene for brown, one for green. Or maybe both brown, hazel is weird. Whatever he has, you definitely inherited a gene for brown from him. That overrides the blue.

But since you have the gene for blue as well, there's a chance you'll pass it along to your kids. If your partner has it also, their eyes might be blue.

Answer 8

It is common practice to distinguish genes through letters.

Brown= BB or Bb or bB

blue= bb

The capital B's are the dominant gene and anytime (even one) is present, the result will be brown eyes.

The lowercase represent the recessive, or blue.

You receive one 'letter' from your mom and one from your dad.

Your dad has brown eyes, so he either has one capital B or two.  The only chance of you having blue eyes would have been for your dad to be heterozygous dominant (having Bb or bB and having brown eyes) and him passing a lowercase b onto you.

That apparently was not the case and you are most definitely Bb or bB.  

Obviously, parents don't give their kids letters, it's more like a certain sequence of nitrogenous bases (in DNA) at a certain allele (a point) on your chromosome.  But I hope this explanation helps.

Answer 9

Brown is dominant over the blue