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Utility of DNA Testing in Genealogical Research Carrie Rowland Mercer County Chapter of Ohio Genealogical Society November 1, 25, 2009 carrie.rowland@wright.edu What is DNA ?
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Utility of DNA Testing in Genealogical Research Carrie Rowland Mercer County Chapter of Ohio Genealogical Society November 1, 25, 2009 carrie.rowland@wright.edu
What is DNA ? The molecules inside every cell in our bodies that carry genetic information and pass it from one generation to the next. This information is the biological and genetic instructions need to build an organism and control day to day functions of all cells. • skin cells • liver cells • brain cells……. It’s all the same !!!!!
Types of DNA Testing : ● Nuclear ● Y Chromosome (Y-STR) ● Mitochondrial (mtDNA) ● Single Nucelotide Polymorphisms (SNPs) ● Paternity
Nuclear DNA Dad Mom X,X X,Y Sex chromosomes
There are two types of DNA – thus, two types of testing: 1 Mitochondria 2 Nuclear DNA: Chromosomes
Types of DNA testing: Nuclear Autosomal ● Unique to a single individual (non-twin). ● Inherited from both parents. ● Similar to a Social Security number. ● Used for Forensic applications or maternity/paternity testing. ● Markers, not genes used for analysis ● Junk DNA – no medical value. ● No help at all with genealogical questions. 2 copies/cell
Two types of DNA: Nuclear Nuclear DNA: • Only two copies/cell. • Inherited from both parents. • Unique to individual. Chromosomes
Types of DNA testing: Nuclear • Strengths: • - Unique to an individual. • Can determine paternity. • At a high level of certainty. • Easy to test for and interpret. • Weakness: • - Recombine = mixing. • - Not helpful in genealogical studies.
Types of DNA testing: Y-chromosome ● IDENTICAL profile in all males in a paternal line. ● Y chromosome passed only from father to son. ● Similar to a Surname in males. ● Used to assist in determining a male line. ● Markers, not genes used for analysis. ● Junk DNA – no medical value. ● Profiles called “haplotypes”.
Types of DNA testing: Y-chromosome • Strengths: • Passed from generation to generation • without change – good lineage markers. • Found only in Males. • Prevalent databases for comparison. • Do not recombine = NO mixing. • Weakness: • Cannot test females for a paternal line. • Difficulty finding a closely related male ? • No male children – line “dies out”. • Unknowns: Adoptions, infidelity….. • Do you really, really want to know ? (~ 1000 genes) (~ 78 genes)
Y-STRs Females: XX Males: XY Y Identical Y Prince Philip Identical Y Prince Andrew Prince Charles Princess Anne
Y-STRs Y Identical Y Identical Y Y Y Identical Y Identical Y X, X X, X Y Y Prince William Prince Harry Princess Eugenie Princess Beatrice
Y-STR testing: Thomas Jefferson and Sally Hemings • Dr. Eugene Foster (1996) – located living relatives of Thomas Jefferson. • Needed direct male descendants from both Jefferson & Hemings lines. • Jefferson had only one son, who died in infancy. • Other possibilities – Jefferson’s brother and a paternal uncle. • Seven living descendant’s of his paternal uncle still alive in 1996. • Even more difficult on the Hemings side. • Only one of three sons could be located, Eston (Jefferson), who had two sons. • Only one living male descending from Eston could be located (Jefferson). • Thomas Woodson Jefferson – Sally’s first child (according to legend). • Samples from Jefferson’s nephews who might have fathered Sally’s children. • Results of 19 markers were evaluated by researchers at Oxford University. • All 19 markers matched between Jefferson and Hemings descendants. • Jefferson at least fathered Hemings last male child ? • Jefferson’s nephew’s markers did not match the Hemings descendant Y markers • Jefferson’s markers did not match Thomas Woodson Jefferson. • In total tested over 15 generations. • Did not have to disturb the burial site of President Jefferson. • However, could another Jefferson male have been the father ? • According to the historical record, 25 adult male Jefferson descendants • lived in Virginia during the time of Ms. Hemings pregnancies.
Y-STR testing: Thomas Jefferson and Sally Hemings • November of 1998 – Nature, 362, 26-27. • January of 2000 – Thomas Jefferson Memorial Foundation • “strong likelihood” (jeffersonondna.com) . • May 2002 – Monticello Association voted to NOT admit • descendants of Sally Hemings into the organization. • - February,2003 - Thomas Jefferson Heritage Society • (ww.tjheritage.org) – “the evidence is not definitive….” • ”the DNA evidence could not specify Thomas Jefferson as • the father to the exclusion of all others”.
Types of DNA testing: Mitochondrial ● IDENTICAL profile in all children from The same mother (maternal line). ● Inherited from MOTHER only. ● Identical profile found in daughters & sons. ● Used for assist in determining a maternal line. ● Markers, not genes used for analysis. ● Junk DNA – no medical value. ● Effective for ancient and degraded samples. 1,7oo/cell
Two types of DNA: Mitochondrial Mitochondrial DNA: •> 1,000 copies/cell. • Maternally inherited. • Not unique to individual. Mitochondria
Types of DNA testing: Mitochondrial • Strengths: • Both males and females can be tested. • Easy to generate a profile – ample material. • Can test ancient and degraded samples. • Test hair, bones and teeth. • Do not recombine = NO mixing. • Weakness: • Hard to correlate with surname. • No female (or any) children – line “dies out”.
Mitochondrial DNA aka:mt-DNA Identical copies go from Mom to ALL of her children male and female. Queen Elizabeth II Identical Identical Identical Prince Andrew Prince Charles Princess Ann
Mitochondrial DNA aka:mt-DNA Mt-DNA from maternal line of Queen Elizabeth II Mt-DNA from maternal line of Lady Diana Spencer Mt-DNA from maternal Line of Lady Sarah Ferguson
Mitochondrial testing: The Romanov Family • Tsar, Nicholas II, the last ruling Russian Tsar. • For the previous 300+ years the Romanov family ruled the • country of Russia. • 1917 abdicated his throne during the Bolshevik Revolution. • 1918 (July), the Romanov family (Tsar Nicholas II, Wife, • Tsarina Alexandra, four daughters and one son were executed • by the Ural Soviets, bodies where burned and buried in two • separte graves. • 1970 the grave of Nicholas, Alexandra and three of their four daughters were located. • 1991 DNA testing was conducted on the remains and compared to present day • descendants. • Nuclear DNA established familial relationship between the Tsar, Tsarina and three of • the female children (paternity testing on nuclear DNA). • mtDNA profiles from Tsarina Alexandra and her three daughters matched the mtDNA • profile of Prince Philip (descendants of the same maternal line - Queen Victoria). • 2007 the grave of two children were found 70 meters from the first grave. • mtDNA test results from bone fragments and teeth indicated an exact match between • the mtDNA profile of Prince Philip confirming that they were the children of Alexandra • Anna Anderson.
Test your own DNA: 12 marker Y-STR test ~ $99 37 marker ~$149 67 makers ~ $248 mtDNA ~ $99 Turnaround time ~ 7 weeks Should only be used in conjunction with traditional genealogical research. Why: The conclusions are not absolute certainties, the DNA evidence lends very strong support to conclusions.
Probability for Most Recent Common Ancestor (MRCA) Familytreedna.com
Mutations A mutation occurs when DNA is copied slightly incorrectly within the body. It is worth noting that this is a natural phenomenon and is indicative of Darwin's 'Theory of Evolution' working at a molecular scale! Problem: Can be difficult to attribute to the proper generation. Calculating time to Most Recent Common Ancestor (MCRA) is based upon probability and is NOT an exact science. We can identify the most likely time that a common ancestor might have lived, but there is always a degree of uncertainty. Think of it as a range rather than a point in time.
Single Nucleotide Polymorphism (SNP) Used to predict ancestral backgroud. A single nucleotide polymorphism (SNP) is a change to a single nucleotide in a DNA sequence. The relative mutation rate for an SNP is extremely low. This makes them ideal for marking the history of the human genetic tree. Very rare - (approx 1/100,000,000 generations) So infrequent that it is reasonable to assume that they have occurred only once in the course of human evolution.
Most Important Slide !!!!!!!! DNA is a science of exclusion, NOT inclusion. DNA testing should be considered only to help verify exhaustive research of the historical record.
Blue Jacket: Where the story began Mr. Robert Van Trees MSgt. Donald Eugene Bluejacket, 1946.
The historical recordWho Was Blue Jacket ? ● Blue Jacket born ~ 1738-1740, died ~ 1808-1810 ● Became Chief early 177o’s ● Consigner of the Treaty of Greenville, August 3, 1795. ● Treaty of Fort Industry (OH), 1805. ● United the fragmented native populations. ● Led a conglomeration of Ohio Indian tribes in several battles against white expansion. Painting by: Howard Chandler Christy, 1945 Signing of the Treaty of Greenville Hanging in the Rotunda of the Ohio Statehouse
The historical recordWho was Marmaduke (van) Swearingen ? ● Born January, 1763 near Hagerstown, Maryland (Swearingen family Bible). ● Dutch descent. ● Moved to Fayette County, PA at the age of seven years. ● Speculated capture about the year 1778 at age 17 years. ● No family or public record speaks of his death.
BlueJacket Lineage •1877 Thomas Jefferson Larsh- grandson of Marmaduke’s sister Sarah. • An Important Historical Letter - “Very interesting facts about a noted Indian chief” 1877 in the Daily Ohio State Journal. • Swearingens incorporated the story into their family genealogies. • Little to no attempts were made to check authenticity • Possibly “embellished” over time.
It doesn’t add up • Blue Jacket was said to have been “captured” or known by Daniel Boone and Simon Kenton – there has never been a single reference indicating that Bluejacket was caucasian. • Joseph and Nancy Moore were noted in a land deed as being “half bloods”. • Diary of a prisoner (Oliver Spencer, 1792) noted Bluejacket as being “the most noble in appearance of and Indian (he) ever saw. • Bluejacket required an interpreter at the signing of the Treaty of Greenville.
Methodology • Buccal swabs from direct male line descendants: • Six individuals from the Bluejacket family (1740) (1970)
Methodology • Buccal swabs from direct male line descendants: • four individuals from the Swearingen family: (1763) (1945)
Methodology • Sample :Buccal swabs from direct male line descendants: • Six individuals from the Bluejacket family • Four individuals from the Swearingen family • Test: Promega Y-Plex 12 test kit that evaluated 12 Y chromosome loci. • Generate results: Generated a haplotype for each family. • Compare to a database: Comparisons made to the Reliagene (3406 ind.) and PowerPlex®(2443 ind.) online Y-STR databases. - no matches to the Bluejacket haplotype - Swearingen family matched:
Y-STR Haplotypes 12 loci Haplotype – consistent at only four of 12 loci What is a feasible mutation rate over seven generations ?? Could these two families actually be Related ??
Conclusions • Considering the mutation rate (~ 1/900 years, it is not very likely that the Marmaduke Van Swearingen was Bluejacket. • Nor is it very likely that the two families are even related in any way via the male line.
Conclusions (In General) What DNA testing CAN do: - Validate in invalidate existing genealogy research (if complete). - Determine if an individual is related to another individual, or a group of individuals. - Identify a common ancestor and infer probability as to when that ancestor likely lived. - Help confirm/nullify surname (and via a common male ancestor). - Help confirm/nullify maternal lines. - Provide clues about ethnic origin. What DNA testing can NOT do: - Cannot determine the degree of blood relationship. - Cannot identify the exact generation, but can identify the most likely time frame. - Not likely to identify down to an exact ancestor with certainty. - Will not reveal any information about your health or predisposition to disease.