Maygra's Musings

I remember reading a sci-fi short story about just that. These kids come to find out that they are the result of some experiment to return to several "pure" racial types. Everyone else in the world has brown hair and eyes and toffee-colored skin. The kids are matched up and expected to breed more of their type. In the end, the kids escape the experiment and the author hints that none of the kids will match up with who they were supposed to. Not sure of who the author is though.