eye color

[saguinaga]

I have blue eyes with blonde hair, my parents both are brown eyed with brown hair. I have 3 brothers two of which, including me, came out with blue and green eyes? how is this possible. my moms parents and my dads parents are the same as my parents brown eyes brown hair. how is this possible 3 out of 4 kids came out with blue and green eyes? please advise.
Also I am 7 months pregnant I have a 2 year old son who has brown eyes with brown hair , my husband has brown eyes also with brown hair. I am expecting this baby to come out with brown eyes as well? want to know your thoughts.
saguinaga

[LazyGun]

It is entirely possible. All down to dominant and recessive characteristics, and which combine and therefore are passed on. It is likely your baby when born will come out with brown eyes, but not absolutely certain.

[ugly_bob]

what colour eyes did the milkman have?

[kujawski]

what about the window cleaner, or the postman?

[jake-the-peg]

As Lazy gun says there are things called recessive genes which basically means characteristics which tend to be overcome by 'stronger' genes but then pop back after a generation.

Say blue eyes is a recessive gene.

A man has blue eyes and marries a woman with brown eyes they have children all of who have brown eyes.

The children still carry the gene for blue eyes - it is just dormant.

One of these brown eyed children marries a partner also with brown eyes and lo and behold some of the children (typically 1 in 4) have blue eyes.

This is the classic example and it can be more complicated but it's the basic principal that you can carry a gene without being affected by it.

[Gnisy]

saguinaga, this isn't really much to worry about and it's all in the genes. Take for instance a couple, one with A type blood and another with B type blood. The posibility of blood types their kids may have may cover A, B, AB and O. For another example out of the textbooks, I have a friend who has an Indian father, a Chinese mother and she came out looking like a Caucasian. Turns out her paternal grandmother was caucasian and the genes skipped a generation and turned up in her.

by the way, if there were no blue-eyed family members in your husband's family then your baby will probably have brown eyes as well.

[wildwood]

To enable brown-eyed parents to have a blue-eyed baby, both parent would have to be carriers of the recessive blue gene. On the average, one brown, two brown/blue carrier, and one blue eyed child will be born. the recessive blue gene can thus be carried for many generations without showing up.
Green eyes are a variant of brown eyes and are rarer than blue.
The hair colour is completely independant from the eye colour. There are also dominant and recessive genes involved.
The only time to worry is when two blue-eyed parents have a brown eyed baby. That is the time to start looking at the milkman.