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Thomas Jefferson and Sally Hemings DNA research

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2026-09-24 19:01 UTC → 2026-09-30 04:04 UTC · added ~~removed~~

Researchers at the Smithsonian Institution have conducted a long-term multidisciplinary investigation to determine the parentage of children born to Sally Hemings, an enslaved woman. Using advanced DNA sequencing and genome reconstruction from hair samples—including a lock taken at Jefferson’s deathbed and strands found in his personal Bible—scientists established a genetic link between Thomas Jefferson and Hemings’ descendants. The study, which spanned at least 15 years, compared Jefferson’s genome with DNA from multiple individuals believed to be his descendants. The findings effectively addressed historical debates by evaluating alternative theories, such as whether Jefferson’s brother, Randolph, was the father; researchers concluded the probability of that being the case was only ‘one in a thousand.’ The evidence is described by project leader Richard Kurin as ‘compelling’ and ‘very clear.’ In the book ‘History by a Hair: Thomas Jefferson, Sally Hemings & Solving a 200-Year-Old Mystery’ by Smithsonian scholar Richard Kurin, the investigation provides what researchers describe as ‘extraordinary proof’ of paternity. By comparing genetic material from Jefferson’s hair with DNA samples from 13 living descendants of both the Jefferson and Hemings families, the study concludes there is a 99.9% probability that Jefferson was the biological father of Hemings’s children, specifically Madison and Eston. ~~The researchers noted~~ Recent analysis of a ~~less than 0.001% chance that he was not~~ reddish-blond hair discovered in Jefferson’s Bible at the ~~biological father~~ Smithsonian National Museum of American History has further refined these ~~two individuals.~~ findings, suggesting a 99.96% chance that Jefferson fathered at least one of Hemings’ children. The Thomas Jefferson Foundation, which operates Monticello, stated that these findings reinforce rather than rewrite the existing historical ~~record. The foundation noted that the study offers an opportunity to reflect on how historical knowledge is acquired and provides~~ record, offering a fuller picture of Jefferson and the world of Monticello.

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