I dunno, the insignifigant amount of Indian (I think it's like 1/32) doesn't bother me, though logically speaking, that's non-white blood. All the non-white I have, as far as I know.
And emotionally speaking, I can understand the unease one would feel finding out you had some black blood, though logically, such small infusions would make no difference.
What I would really hate, is if some good white person, especially a racially conscious one, found out that like his great-great grandfather was married to a mullato or something, and freaked out, maybe even had a change of heart. He'd still be who he is, I mean, white for all intents and purposes. Theres probably no such thing as an absolutely pure race, at the very least us and the ******** share a common ape-creature as an ancestor. And even some of the blacks make decent folks, when you get down to it.