I don't think it really means anything either, but it is interesting. The extent to which white folks had to hide their African ancestry. Most white people who have been on this land mass for more than a few centuries have Black ancestry, as do Black people with the same tenure have white ancestry.
There are at least six American presidents with Black ancestry, Barack Obama, Andrew Jackson, Abraham Lincoln, Warren G. Harding, Calvin Coolidge, and Dwight D. Eisenhower. Of course, most of these men would have done everything in their power to hide any evidence of Black ancestry.
J.A. Rodgers published a 22-page book The Five Negro Presidents, in which he provides evidence. Rodgers, for obvious reasons, has been marginalized.