"[On Jefferson's relationships with Sally Hemings and the likelihood of his DNA providing evidence of their living descendants.] I would not characterize it as an affair, or suggest that the relationship can be understood in modern terms. On Jefferson's isolated mountaintop, sex took place as part of a hierarchy that everyone involved understood. Jefferson, and those of his class, did not share our current understanding of sexual morality. Sally Hemings was his servant, and had little power. She was dependent economically, though this does not mean her feelings were irrelevant. But it does mean that he had extraordinary power, and she very little, and so, as his concubine, she had probably replicated her mother's relationship with Jefferson's father-in-law; for she was, in fact, Jefferson's late wife's half-sister, and I have described the Hemings family as a parallel, subordinate family to the all-white Jeffersons. ... Technically, there were other Jeffersons with matching DNA characteristics, but the white Jefferson descendents who established the family denial in the mid-nineteenth century cast responsibility for paternity on two Jefferson nephews (children of Jefferson’s sister) whose DNA was not a match. So, as far as can be reconstructed, there are no Jeffersons other than the president who had the degree of physical access to Sally Hemings that he did."