Technically, blue eyes are already a genetic mutation. So...

Mutations can mutate. Assuming you believe in evolution, we're all the product of beneficial mutations heaped upon each other.

Damn

All these commenters acting like this is no big deal and OP is somehow ungrateful. It is a big deal to find out you're adopted and that your folks never told you. And OP might be very grateful for his or her parents. Doesn't stop it being a big thing to find out you have other family out there somewhere.

I'm adopted too OP, I can relate! Perhaps they didnt tell you because they didnt want to upset you, or they weren't ready. Just sit down with them have a chat! What's meant to be will be, and adopted or not, you're still a blessing to them. :)

You have parents who love you, is that really so bad? It's quite possible that it was never an issue for them so they never told you, because they cared for you so much.

It could have been much worse. You could have NOT been adopted and you'd be doing this game with no parents. Nothing wrong with being adopted unless your adopted parents are abusive. Do you really have it so bad?

Oh yes, fun genetics games in biology. I spilt a beaker of "genes" (coloured beads) over the floor and I never heard the end of it.

This actually happens quite a few times in biology classes while doing Punnet squares. A biology class I was in (I'm in college), we learned about Punnet squares and my instructor told us she's had people discover that they're colorblind. It's amazing.

We adopted and had a biological child, so you're definitely not alone.