User:MalcolmJamesAlex/Jefferson-Hemings DNA Testing

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Jefferson-Hemings DNA Testing Introduction Descendants of Thomas Jefferson’s slave, Sally Hemings, claim to be the children of both Hemings and Jefferson. Their declaration caused a major conflict between the two families, Hemings and Jefferson, because the Hemings children based their claims on family oral tradition. Jefferson descendants, who have unlimited documentation of their blood relationship to the Founding Father, denounced the Hemings oral tradition as insufficient and demanded concrete proof. Thus, in 1998, Dr. Eugene Foster and a team of geneticists tested Y-chromosome DNA samples from the Jefferson line and found a link between the Hemings descendants and Jefferson. However, the controversy surrounding the situation still remains today.

The Dispute between the Jefferson family and the Hemings family

Jefferson Side Jefferson descendants deny the Hemings and Jefferson relationship for numerous reasons. For one, they believe the relationship was a slur spread by a “disappointed office-seeker” named James T. Callendar who was trying to ruin Jefferson’s chances of a second presidential term for his own personal gain. Jefferson descendants also believe “moral and practical grounds” made it impossible for the relationship to occur. In regards to the DNA test conducted by Dr. Eugene Foster, the Jeffersons disagree with the conclusion of the results [that Jefferson fathered Hemings’ children] because other adult male Jeffersons visited Monticello at that time carrying the same Y-chromosome as Jefferson, making them possible fathers of Hemings’ children. Finally, Jefferson descendants feel that the gaps in Hemings’ genealogy and the lack of documentation of the Hemings family make it impossible to ever be certain of whether or not the Hemings and Jefferson relationship could have taken place.[1]

Hemings Side Hemings descendants are confident they are the children of Hemings and Jefferson. The Hemings family has passed on their history via oral tradition and are able to formulate a genealogy that connects them all the way back to Hemings and Jefferson. For instance, in Jefferson’s Children, author Shannon Lanier, a Hemings descendant, can trace his lineage from himself to Madison Hemings, who is the son of Jefferson and Hemings. The Hemingses also believe in the validity of the positive DNA results because the outcome not only confirmed their oral tradition but also provided written documentation for their family history.[2]

Hemings' Oral Tradition Sally Hemings is the daughter of Elizabeth Hemings and John Wayles. John Wayles is the father of Sally Hemings and Martha Wayles, Thomas Jefferson’s wife. Therefore, Martha Jefferson and Sally Hemings are step-sisters. Martha Jefferson dies in 1782. Thomas Jefferson is posted to Paris, and Sally Hemings joins him in Paris to care for his daughter in 1787. Thomas Jefferson is elected president in 1800 and serves two terms. Thomas Jefferson retires to Monticello in 1810 and dies in 1826. Sally Hemings dies in 1835. Thomas Jefferson and Sally Hemings have children between 1795 and 1808. Madison and Eston Hemings are notable because Thomas Jefferson freed them in his will.[3]


DNA in the American Court System The use of DNA in the American judicial system has grown exponentially over the past 30 years, evolving from an unreliable and questioned science to a powerful tool in legal cases. From paternity tests, to definitive evidence in capital crimes, DNA has become a staple within the American legal system. DNA has become immersed in the public eye through a combination of various high profile cases and media outlets such as popular television shows and movies[4] . DNA evidence has been used extensively to not only prosecute defendants, but to overturn wrongful convictions as well. The first ever court case to use DNA in the United States of America took place in Orange County, Florida in 1987, as the definitive piece of evidence in a rape trial[5] . The defendant Thomas Lee Andrews was found guilty after his DNA matched the DNA found inside the rape victim, and was sentenced to serve a prison term of 22 years[6] . He was subsequently convicted of first-degree rape and sentenced accordingly. When done correctly, forensic DNA testing has an accuracy of better then 99%[7] , and while DNA is used often and is seen as authoritative and definitive evidence in linking people together, it is not without skeptics.


DNA Controversy There have been many controversies surrounding the use of DNA evidence in the court of law. Much of the uncertainty surrounding DNA stems from its relative newness to the judicial system combined with the power it holds to determine prison time, often including life sentences. The groundbreaking case that took away credibility from DNA testing and launched wide spread skepticism was The People of New York v. Castro[8] , where Joseph Castro was on trial for the murder of his neighbor’s daughter. During the trial it was revealed that there had faulty laboratory testing procedures, yet the court still allowed the DNA evidence into the trial, and Castro was released as a result[9] . The shaky nature of DNA during this high profile trial launched wide spread criticism and skepticism about DNA which persisted for decades.


DNA Testing As stated, there has been much debate concerning the validity of the Jefferson-Hemings paternity DNA test. The recent discovery of DNA testing allowed scientists and other experts in the field of genetics to speculate whether the results of the DNA test should be the resolute answer to the controversy. The comparison of the Y-chromosomal DNA haplotypes from a male-line descendant of Field Jefferson, a paternal uncle of Thomas Jefferson, should have settled the dispute, however, speculation continued. The DNA test in conjunction with the oral stories and written documentation should help to pinpoint the paternity of Sally Heming’s children.


Procedure Dr. Eugene Foster, a retired professor of pathology at Tufts University and the University of Virginia, designed and executed the entire DNA test which confirmed that Thomas Jefferson was the father of at least one of Sally Heming’s children[10] . The test allowed Dr. Foster to find and isolate the Jefferson Y chromosome. Y chromosomes are passed unaltered from father to son, and aside from occasional mutations, a DNA analysis of the Y chromosome can reveal whether or not individuals are likely to be male-line relatives. Five male-line descendants of two sons of the president’s paternal uncle, Field Jefferson; five male-line descendants of two sons of Thomas Woodson; one male-line descendant of Eston Hemings Jefferson; and three male-line descendants of three sons of John Carr, grandfather of Samuel and Peter Carr. Seven bi-allelic markers, eleven microsatellites, and the minisatellite MYS1 were analyzed[11] .


Figure 1 Male-line ancestry and haplotypes of participants. a, Ancestry. Numbers correspond to reference numbers and names in more detailed genealogical charts for each family. b, Haplotypes. Entries in bold highlight deviations from the usual patterns for the group of descendants. Bi-allelic markers. Order of loci: YAPSRYm8299-sY81-LLY22g-Tat-92R7-SRYm1532. 0, ancestral state; 1, derived state. Microsatellite short tandem repeats (STRs). Order of loci: 19-388-389A-389B-389C-389D-390-391-392-393-dxys156y. The number of repeats at each locus is shown. Minisatellite MSY1. Each number in brackets represents the sequence type of the repeat unit; the number after it is the number of units with this sequence type. For example, J41 has 5 units of sequence type 3, 14 units of sequence type 1, 32 units of sequence type 3, and 16 units of sequence type 4.x[12]


Results Four of the five descendants of Field Jefferson shared the same haplotype at al loci, and the fifth differed by only a single unit at one microsatellite locus. This haplotype is rare in the population, where the average frequency of a microsatellite haplotype is about 1.5%. Four of the five male-line descendants of Thomas Woodson shared haplotype that was not similar to the Y chromosome of Field Jefferson but was characteristic of Europeans. The fifth Woodson descendant had an entirely different haplotype, most often seen in sub-Saharan Africans, which indicates illegitimacy in the line after individual W42. The descendant of Eston Hemings Jefferson did have the Field haplotype. The haplotype of two of the descendants of John Carr were identical, and the haplotypes differed markedly from those of the descendants of Field Jefferson[13] .


Conclusion The most probable explanation for the molecular findings is that Thomas Jefferson was the father of Eston Hemings Jefferson, and that Thomas Woodson was not Thomas Jefferson’s son. The frequency of the Jefferson haplotype is less than .01%[14] .

References[edit]

       By. "A Brief History of DNA Testing - TIME." Breaking News, Analysis, Politics, Blogs, News Photos, Video, Tech Reviews - TIME.com. TIME. Web. 30 Nov. 2010. <http://www.time.com/time/nation/article/0,8599,1905706,00.html>.
      "Evolution of DNA Evidence for Crime Solving - A Judicial and Legislative History." Forensic Magazine. Forensic Magazine. Web. 14 Nov. 2010. <http://www.forensicmag.com/article/evolution-dna-evidence-crime-solving-judicial-and-legislative-history?page=0,0>.
      "Frontline: the Case for Innocence: the Dna Revolution: the Dna Wars Are over." PBS: Public Broadcasting Service. PBS. Web. 15 Nov. 2010. <http://www.pbs.org/wgbh/pages/frontline/shows/case/revolution/wars.html>.
      Lanier, Shannon, and Jane Feldman. Jefferson's Children: the Story of One American Family. New York: Random House, 2000. Print.
      Madison's, By. "Thomas Jefferson and Sally Hemings: A Brief Account « Thomas Jefferson’s Monticello." Thomas Jefferson’s Monticello. Web. 30 Nov. 2010. <http://www.monticello.org/site/plantation-and-slavery/thomas-jefferson-and-sally-hemings-brief-account>.
     "Frontline: Jefferson's Blood: Interviews: Dr. Eugene Foster | PBS." PBS: Public Broadcasting Service. PBS. Web. 14 Nov. 2010. <http://www.pbs.org/wgbh/pages/frontline/shows/jefferson/interviews/foster.html>.
     
      Foster, Eugene A., M. A. Jobling, P. G. Taylor, P. Donnelly, P. De Knijffs, Rene Mieremets, T. Zerjal, and C. Tyler-Smith. "Jefferson Fathered Slave's Last Child." Nature 396 (1998): 27-28. Print.