Question: Another important set of samples for testing was gathered from direct male-line descendants of Samuel and Peter Carr, who were Thomas Jefferson's nephews, the sons of his sister. According to Thomas Jefferson's grandchildren Thomas Jefferson Randolph and Ellen Coolidge, Samuel and Peter Carr were the fathers of the children of Sally Hemings and her sister. Dr. Foster collected three blood samples from living descendants of John Carr, the grandfather of Samuel and Peter Carr. Finally, fi ve male descendants from several old-line Virginia families around Charlottesville were sampled to serve as control samples. These controls were tested to provide a ‘ background 'signal with the idea that potential similarities in the Y-chromosome tests due to geographic proximity needed to be eliminated. Inall, 19 Y-chromosome markers were examined in this study. These included 11 STRs, seven SNPs, and one minisatellite MSY1, which proved to be the most polymorphic marker. All 19 regions of the Y chromosome examined in this study matched between the Jefferson and Hemings descendants. These DNA results were viewed by Dr. Foster and his coauthors as evidence for President Thomas Jefferson fathering the last child of Sally Hemings. The John Carr lines differed signifi cantly from the Jefferson - Hemings results with at least 7 of the 19 tested DNA markers giving different results. Thus, neither Samuel Carr nor Peter Carr was the father of Eston Hemings. The results of the Virginia old-line families were not reported, presumably because these samples served their purpose as effective controls and revealed no unusual Y-chromosome patterns. Shortly after the results of Dr. Foster's study were announced, an alternative scenario was proposed. Could some other male Jefferson have fathered Eston Hemings? All the results in this study conclusively show is that there is a genetic match between descendants of Eston Hemings and Thomas Jefferson's uncle, Field Jefferson. Was it historically possible for another male Jefferson to have fathered Sally Hemings's children? The Thomas Jefferson Memorial Foundation, a private,
nonprofi t organization established in 1923 that owns and operates Monticello with the goal of preservation and education, conducted a yearlong investigation into the historical record. According to this careful historical investigation, 25 adult male descendants of Thomas Jefferson's father Peter and his uncle Field lived in Virginia during the 1794 - 1807 period of Sally Hemings's pregnancies (Monticello, 2000). Most of them lived over 100 miles from Monticello and make no appearance in Thomas Jefferson's correspondence documents. Several male Jeffersons including President Jefferson's brother Randolph and his sons did live in the area of Monticello and visited occasionally. However, the historical records fail to indicate that any of these individuals were present at Monticello 9 months before the births of Sally Hemings's children. This information combined with the fact that Thomas Jefferson was present at Monticello during the time of conception of each of Sally Hemings's six children led to the 26 January 2000 Thomas Jefferson Memorial Foundation report that he was the father of all of Sally Hemings's children. A more recent study by a 13-member Scholars Commission of the Thomas Jefferson Heritage Society unanimously agreed that the allegations of a relationship are ‘ by no means proven. ' The findings of this group are reported in a 565-page report available at the Heritage Society's Web site: https://www.tjheritage.org . This report notes that the original DNA study indicated only that a Jefferson male had fathered one of Sally Hemings's children and that the available DNA evidence could not specify Thomas Jefferson as the father to the exclusion of all other possibilities . Thomas Jefferson's younger brother Randolph, who was known to fraternize with the Monticello slaves, is considered a likely possibility by many members of the Scholars Commission. Randolph and other family members would have visited Monticello when President Jefferson was home and therefore the circumstantial evidence of Thomas Jefferson being present on the plantation when Sally Hemings conceived might not be as strong as originally presented. This study of Jefferson lineage DNA demonstrates one of the major disadvantages of Y-chromosome DNA testing, namely that results only indicate connection to a male lineage and are not specific to an individual like autosomal STR pro- fi les can be. While a Jefferson Y-chromosome match exists between his descendants and those of Sally Hemings, the matter can probably never be definitely solved by Y-chromosome information alone.