>>159045675/16 black would appear to be about 1/3rd on a DNA test. There was so much nigger colonialism goblino action going on though in the last 400 years that there are all number of ways it could come about.
What is more likely is that a rare white person mixed with blacks a long time ago, and that DNA got tossed around again and again and with others like them, then in modern times a white person mixes with them and produces someone like that. Seems to happen most often with a white man and mullato women. Same thing that spawned pic related, another ~1/3rd black.
