What i'm thinking is that it's *possible
(barring the possibility that these genes were passed down from master-slave, which is also possible. As an African American that possibility is undoubtedly there and i'm sure exists somewhere. However experience has also taught me that genetic legacies are often not what you think as well. Such as the fact that Africans and Irish intermarried in the Caribbean after some Irish were taken as slaves, a term for this called "Barbadosed". So for now I am thinking in the hypothetical until I get more evidence)
that there is some genetic similarity between the person my grandmother matches, and their old world genetic components and the new world indigenous groups that seem to continue to pop up for all of us at different frequencies (Greater for grandmother, second for mum, and then me. If I remember, not so much for my uncle and grandfather).