Maybe someone here can clear this up as I've been reading conflicting information. My sister is the only person in my family with brown eyes. I'm wondering if perhaps she has a different father than me. My parents both have green eyes. My mothers father has blue eyes and her mother has green eyes. My fathers mother had blue eyes and his father had green. My brother has blue eyes and I have green. My sister has dark brown eyes....... Wtfk...

Most likely had a brown eyed father, though it's technically possible for 2 green eyed people to have a brown eyed child, but very rare (much rarer than women having children with men who aren't their husband).
I wouldn't mention it though unless you had some corroborating evidence.. and even then probably best to just ignore it

this

best to leave those kinds of things alone.

the eye colour example is often times used in high school biology text books as an example for mendelian genetics that can be solved using a punnett grid

truth is, it's not. Eye colour isn't that simple (and neither are many other genetic things)

This lol... exceptions and examples are numerous!
The basic genetic analysis you've done won't really prove anything and would just start a painful drama of sorts lol.

I think the only way is for you to grab two comparable samples of DNA and test them in your own Dexter's Lab.... or hand over about a couple grand and get it done by a pro.

Or just go here... for the low price of twenty nine ninety fiveeee (hi doctor nick):
SwabTest on google

This post was edited by AF_bear on Jul 31 2012 01:47pm

Hm... this is interesting. I had one additional question, and this one I know absolutely nothing about. I have type O- blood, so does my brother. I've been told by my girlfriend that both of my parents must then have type O blood. My sister has AB+ blood....... Is it possible for two parents with type O blood to have a child without it?

you may wanna ask for your parents blood type. if you find them out, heres a quick link that you can input the parents bloodtpyes. sounds to me like yoru sister may be adopted or have a different parents somewhere.
a girl in my bio class found out she was adopted after we did a blood typing lab.
http://www.biology.arizona.edu/human_bio/problem_sets/blood_types/inherited.html

That doesn't guarantee your parents have type O blood. If one has type B and one has type A then they can have both AB or O children (or A or B for that matter).
If your parents are both type O though then it's pretty conclusive.

This post was edited by taekvideo on Jul 31 2012 02:59pm

You and your sister both have the same biological mother and father, but your sister's biological grandfather was a Muslim