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mizzfizz
May 14, 2007, 06:24 AM
Can two blue eyed parents make a brown eyed child?
And can two brown eyes make a blue eyed child?

templelane
May 14, 2007, 07:12 AM
Eye colour comes from one gene right? Nope you got lied to at school about that one it is actually polygenic despite always being used to describe a discrete phenotype. Eye colour comes form the interaction of several genes- I think it's considered to be about 8 at the moment. So depending on the combination of all the eye colour genes you receive will determine the colour of the eyes. Certain combinations are going to be more likely that others in the progeny - therefore it is common to share your parents eye colour.

Also you have to consider genetic mutations causing one of the eye colour genes or related associated proteins in expression- these would cause a different eye colour than what you would expect form inheritance alone.

So you can see it is possible and observed.

If you want to know where the genes are located look at this site - it also confirms that this happens
OMIM - EYE COLOR 1; EYCL1 (http://www.ncbi.nlm.nih.gov/entrez/dispomim.cgi?id=227240)

mizzfizz
May 16, 2007, 03:09 AM
So what's the answer yes or no??

Curlyben
May 16, 2007, 03:21 AM
NO
And
YES
Or is it
YES
And
NO
Or maybe
BOTH!
I forget.

dannysmom
May 16, 2007, 05:28 AM
Case in point husband and I both brown, sun has blue
If two blonds have a brown , wife has some explaining to do.

templelane
May 16, 2007, 07:56 AM
Sorry It's yes it is possible - the link to online mendelien inheritance in man confirms this - I just thought you might wish to see it straight from a reputable source. Sorry for any confusion I was in exam mode!

LadyB
May 16, 2007, 08:22 AM
It is very, very rare for two blue eyed parents to have a brown eyed child due to blue eyes being a non-dominant trait, but it can happen due to the more complex interplay of genes the previous poster discussed.

Brown eyed couples can and do have blue eyed children fairly regularly, due to many brown eyed people having a blue recessive gene due to one blue eyed parent themselves.

For example both my parents have brown eyes, but they each had one blue eyed and one brown eyed parent, so I could have easily had blue eyes.

mizzfizz
May 16, 2007, 08:23 AM
I thought goldfish has white spot oe black spot, not pimples... wot like acne??