In order to answer the question of whether or not Thomas Jefferson could have been the father of any of Sally Hemings' sons it is necessary to compare the Y-chromosome DNA from the living male-line descendants of Jefferson and Hemmings. Is has been possible to locate male-line descendants of two of Sally Hemings' sons, Thomas Woodson (the oldest) and Eston Hemings the (youngest), but not Madison Hemings whose male-line descendants did not survive the Civil War. Shown in the figure to the right is the lineage of the one male-line descendant (H21) of Eston Hemmings and the five male-line descendants (W55, W56, W69, W70, and W61) of Thomas Woodson whose DNA was analyzed as part of the study.
Furthermore, Thomas Jefferson did not have a son survive to reproduce so it was necessary to locate the male-line descendants of Thomas Jefferson's paternal uncle, Field Jefferson. Five such descendants (J41, J42, J47, J49, and J50) were located and their DNA was analyzed.
It was also possible to locate three male-line descendants (C27, C29, and C31) of Samuel and Peter Carr -- the sons of Thomas Jefferson's sister -- whom some consider as the possible fathers of Sally Hemings' children.
In the table below are the results of an examination of the Y-chromosome DNA of the 14 male-line descendants described above. Where an individual differs from the other members of his cohort, the allele difference is shown in bold face. The five descendants of Field Jefferson (and proxies for Thomas Jefferson) have identical Y-chromosome DNA alleles except for one microsatellite DNA from J50. This difference is most reasonably accounted for by assuming that a mutation occured.
The lone descendant of Eston Hemings has the same set of Y-chromosome DNA alleles as the descendants of Field Jefferson. This supports the claim that Thomas Jefferson could have been the father of Eston Hemings although it does not prove it since the father could have been any male who had the same Y-chromosome as Thomas Jefferson and was in the immediate vicinity of Sally Hemings nine months before the birth of Eston Hemings. In fact, historical evidence implicates Randolph Jefferson, Thomas' brother, as the more likely father of Eston Hemings. The Carr descendants have similar DNA among themselves but are clearly different from either the Jefferson or Hemings descendants.
Four of the descendants of Thomas Woodson are quite similar among themselves but different from Jefferson and Hemings although they do have similarities to the descendants of the Carr line. One of the Woodson descendants is quite different from all of the other individuals which suggests that one of the genetic ancestors was not in the direct line from Thomas Woodson.
Family | Pedigree Member |
Bi Allelic Markers | Microsatellite STR | Mini Satellite MSY1 |
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Jefferson | J41 | 0000001 | 15,12,4,11,3,9,11,10,15,13,7 | (3)5, (1)14, (3)32, (4)16 |
J42 | 0000001 | 15,12,4,11,3,9,11,10,15,13,7 | (3)5, (1)14, (3)32, (4)16 | |
J47 | 0000001 | 15,12,4,11,3,9,11,10,15,13,7 | (3)5, (1)14, (3)32, (4)16 | |
J49 | 0000001 | 15,12,4,11,3,9,11,10,15,13,7 | (3)5, (1)14, (3)32, (4)16 | |
J50 | 0000001 | 15,12,4,11,3,9,11,10,16,13,7 | (3)5, (1)14, (3)32, (4)16 | |
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Hemings | H21 | 0000001 | 15,12,4,11,3,9,11,10,15,13,7 | (3)5, (1)14, (3)32, (4)16 |
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Carr | C27 | 0000011 | 14,12,5,12,3,10,11,10,13,13,7 | (1)17, (3)36, (4)21 |
C29 | 0000011 | 14,12,5,11,3,10,11,10,13,13,7 | (1)17, (3)37, (4)21 | |
C31 | 0000011 | 14,12,5,12,3,10,11,10,13,13,7 | (1)17, (3)36, (4)21 | |
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Woodson | W55 | 0000011 | 14,12,5,11,3,10,11,13,13,13,7 | (1)16, (3)27, (4)21 |
W56 | 0000011 | 14,12,5,11,3,10,11,13,13,13,7 | (1)16, (3)27, (4)21 | |
W69 | 0000011 | 14,12,5,11,3,10,11,13,13,13,7 | (1)16, (3)27, (4)21 | |
W70 | 1110001 | 17,12,6,11,3,11,8,10,11,14,6 | (0)1, (3a)3, (1a)11, (3a)30, (4a)14, (4)2 |
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W61 | 0000011 | 14,12,5,11,3,10,11,13,13,13,7 | (1)16, (3)28, (4)20 |