The color of the Eyes

[Michael Liss t3173]

Well, I'm not exactly sure weather this is the right group for such a question.
Here it is anyway:

What is the stuff that gives the eyes their color?
How can it be Blue/brown/green?
Albinos have no color at all. So it must have something to do with
the melanin pathway. 
If you know what the chromophor is do you also know what protein it is 
associated with?

Anxiously waiting for an answer

Mike

Michael.Liss at biologie.uni-regensburg.de