For more than 200 years, one question about the nation's third president has lingered: Did Thomas Jefferson father children with Sally Hemings, a woman 30 years his junior whom he held in slavery?
The question has long been part of debates over slavery, race, power and Jefferson's legacy.
"Thomas Jefferson wrote the most famous phrase in American history — 'All men are created equal' — and yet, if he bore children with Sally Hemings who were born into slavery, it seemed like a paradox and a contradiction," Richard Kurin told NPR's Michel Martin for Morning Edition.
Kurin, a distinguished scholar and ambassador-at-large for the Smithsonian Institution, spent 15 years searching for Jefferson's DNA in an effort to answer the paternity question. The investigation began with strands of hair found in Jefferson's personal Bible and eventually involved scientists, archaeologists, genealogists, forensic experts and Jefferson's and Hemings' descendants.
The investigation's twists, as well as the science behind it, are detailed in Kurin's new book, History by a Hair.
Two centuries of questions
Jefferson was the principal author of the Declaration of Independence. Allegations that he fathered children with Hemings emerged in the late 1700s and early 1800s and have been debated by family members, biographers and historians ever since.
Kurin and his team were not the first to turn to DNA.
In the late 1990s, pathologist Eugene Foster and colleagues analyzed Y chromosome markers from Jefferson's family descendants and a descendant of Eston Hemings.
"He [Foster] found contemporary descendants who had the Jefferson Y chromosome, and then he found the descendant of Eston Hemings, Sally Hemings' youngest son. Coupling the historical evidence with that DNA evidence, it convinced, I think, most historians and a lot of people that Thomas Jefferson was indeed the father of Sally Hemings' children," Kurin said. But others objected by noting that the DNA results then could point to any Jefferson male, such as a cousin, brother or nephew.
Outside of science, other questions remained.
"Some have said, 'Well, you know, she was enslaved. It had to be coercive. It by definition had to be rape because she can't consent," Kurin said. "Other people have said, 'Well, here was a young woman 30 years younger than Jefferson who had tremendous agency,'" he added.
Kurin enlisted Beth Shapiro, a MacArthur fellow who works with ancient DNA from extinct species, and Richard "Ed" Green, an expert in paleogenomics and forensic genomics. Both are at the University of California, Santa Cruz.
Kurin said his project focused on scientific evidence void of "moralizing or judging Jefferson" in their quest for answers. In his time, Jefferson kept more than 600 enslaved people who cultivated tobacco and mixed crops and ran his primary home and plantation, Monticello, near Charlottesville, Virginia.
A lock of hair
About five years into the investigation, Kurin and his team discovered that the strands of hair found in Jefferson's Bible did not belong to Jefferson.
But Kurin kept looking.
He went back to Monticello and pulled from a packet of hair that was not in the initial inventory.
"A rich lock of hair," Kurin said. "You open up the packet, and here is Thomas Jefferson's hair, like a nice lock of hair staring in the face — looked very rich and that hair yielded DNA," Kurin said. "The key to sequencing his DNA."
The packet was labeled as Jefferson's hair, cut the day he died, July 4, 1826.
"That was the, you know, the key to sequencing his DNA," Kurin said.
With this new DNA sample, the results appeared to be conclusive.
"We know that there are descendants of Madison Hemings and Eston Hemings that have a whole lot of Thomas Jefferson DNA," Kurin said, referring to Sally Hemings' two youngest surviving sons. "You actually had Hemings descendants that had more Thomas Jefferson DNA than the known Jefferson descendants."
He added: "I wouldn't make it a rule that the Hemings necessarily have more, but the Hemings certainly had more than was expected."
Asked whether the findings answer the question of whether Jefferson fathered children with Hemings, Kurin said yes.
"The DNA speaks for itself."
The researchers were able to identify descendants of Madison Hemings and Eston Hemings, but not of Sally Hemings' other surviving children, Harriet Hemings and Beverly Hemings.
"Her two other children, Harriet and Beverly, a boy and a girl, basically ran off from Monticello," Kurin said. "Jefferson let them run off in 1822. They went to Washington, D.C. They passed as white, and they had families, and so nobody knows about their descendants."
Kurin hopes to make Thomas Jefferson's genome publicly available, which could help others trace connections to his family. A scientific paper is currently under review for publication.
"They may end up rediscovering a heritage that was obscured. This story is not over yet," he said.
Lilly Quiroz produced the radio interview. Majd Al-Waheidi edited and produced the digital story.
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