Alternative Scenarios

Shortly after the results of Dr. Foster's study were announced, an alternative scenario was proposed. Could some other male Jefferson have fathered

Thomas Jefferson II _I_

Field Jefferson _I_

Jefferson Y Haplotype

Jefferson Y Haplotype

Peter Jefferson

President

Thomas Jefferson ?

Eston Hemings

Same Y Haplotype

Thomas Woodson

Different Y Haplotype

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, non-profit 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 nine 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 (Monticello 2000).

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: http://www.tjher-itage.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 profiles 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.

SURNAME TESTING AND GENETIC GENEALOGY

Genealogists in large numbers are beginning to turn to Y chromosome DNA testing to extend their research efforts (Brown 2002). Tens of thousands of genetic genealogy tests, primarily Y-STR typing of one to two dozen loci, are being conducted by several commercial enterprises (D.N.A. Box 9.2). Oxford Ancestors (Oxford England), Family Tree DNA (Houston, TX), Relative Genetics (Salt Lake City, UT), and DNA Heritage (Dorset, England) offer Y-STR testing specifically for surname testing.

D.N.A. Box 9.2 The emerging field of

A number of so-called 'genetic genealogy' companies have begun offering DNA testing services to avid family historians in order to help establish links between related individuals when the paper documentary trail runs cold (Brown 2002). The major assumption behind these efforts is that surnames, which generally are passed on from father to son, can be correlated to Y chromosome haplotype results. An early study with four Y-STR markers found a common core haplotype in 21 out of 48 men with the Sykes surname (Sykes and Irven 2000). Unfortunately, illegitimacy, adoption, and Y-STR mutations introduce a level of ambiguity into results (see Jobling 2001b). Nevertheless, this field is taking off quickly with demands for higher numbers of tested markers than are currently used in the forensic DNA typing community.

Below is a list of the companies offering Y-STR 'surname' (paternal lineage) testing and mitochondrial DNA 'maternal lineage' testing for genealogical purposes. Each company has its own database to enable comparisons to those with similar DNA results. The number of Y-STR markers offered in the various company tests as of January 2004 is also listed. Most mitochondrial DNA sequence results are for hypervariable region I only.

Family Tree DNA

(Houston, TX and Tucson, AZ) http://www.familytreedna.com 12, 25, or 37 Y-STRs

Relative Genetics/GeneTree/ Ancestry.com

(Salt Lake City, UT and San Jose, CA) Associated with Sorenson Genomics (BYU Molecular Genealogy Group) http://www.relativegenetics.com http://www.genetree.com 26 Y-STRs

Oxford Ancestors

(Oxford, England) http://www.oxfordancestors.com 10 Y-STRs

Trace Genetics

http://www.tracegenetics.com Focuses on Native American lineages

African Ancestry

(Washington, DC) http://www.africanancestry.com Focuses on African-American lineages 9 Y-STRs

DNA Heritage

(Dorset, England) http://www.dnaheritage.com http://www.ybase.org 21 Y-STRs

DNA Print Genomics

(Sarasota, FL)

Use SNPs to estimate ancestry http://www.dnaprint.com http://www.ancestrybydna.com 71 or 175 autosomal SNPs

Genetic genealogy using Y chromosome STR markers in conjunction with surname studies originated with a study published by Bryan Sykes in 2000 (Sykes and Irven 2000). Using four Y-STRs, DYS19, DYS390, DYS391, and DYS393, Sykes tested 48 men bearing the surname Sykes sampled from several regions of England. Of the 48 tested, 21 of them exhibited the core 'Sykes' haplo-type and several others were only one mutational step away from the core hap-lotype. Sykes interpreted these results to reflect a common origin coming from an ancestor that lived about 700 years ago. While some interesting connections are being made with DNA to aid genealogical research, the field is still in its infancy and results should be interpreted with caution.

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