I don't know how that works. It would be so little and so far back it would be diluted by the time I came around.
Don't let people make you feel ashamed of the blood and DNA you have. It's diluted but it's still a dominant gene. There have been stories of two whites having kids, baby comes out with black features. Husband gets pissed, they do a DNA test and find out no one cheated. They do DNA test on both of mama and daddy and it turns out daddy had negro in his family tree he didn't know about. I don't know if he recovered...lol
It obviously won't win you any cool points in the white community but how would your great-great grandfather feel if he knew his great great grandson shunned his great-great grand mother because she's mixed. Not too happy Id imagine...Be happy with who you are...Every part...As I am.