Sunday, April 5, 2015

Jumping to Conclusions with Genealogy and DNA

In genealogy research, as well as genetic genealogy, jumping to conclusions is easily done. Researchers may find something or someone that looks like a promising clue to tracing back further, or researchers may even find something or someone that looks exciting and appears to be connected. Before we know it, we are deeming that research finding as a factual connection BEFORE more in-depth research reveals something otherwise. In other words, reasonable assumptions convert to bona fide conclusions without a reasonably exhaustive search for all pertinent information. In many cases, the closer analysis or more in-depth research never happens. Consequently, many erroneous family trees or pedigree charts are being shown or false information is being presented. I was guilty of this recently.

Now that genetic DNA technology has come onto the genealogical scene, jumping to conclusions is even easier, unfortunately. Let’s face it. Many of these conclusions could be wrong as two left shoes. Why? Here are several reasons why many conclusions could possibly be wrong:

1.    Some researchers have based their conclusions on one person’s DNA results. More accurate conclusions can be drawn from analyzing multiple family members’ results.
2.    Some researchers overlook the chance that their initial analysis is wrong because the finding is exciting, interesting, and seems to fit. Therefore, they fail to examine the contradictory evidence.
3.    Some researchers often erroneously conclude that just because two or three people are someone’s DNA matches too, then they all must descend from the same ancestor. They often fail to consider that with autosomal DNA test results from 23andMe, FamilyTreeDNA, AncestryDNA, or GEDMatch, our DNA matches may be maternal relatives or paternal relatives. That’s why DNA triangulating is very important and ensuring that the people in question all match each other.
4.    Also, a misunderstanding of DNA technology or a gross lack of knowledge about DNA can often lead to many erroneous conclusions.

Recently, I decided to ask my mother’s brother to take the 23andMe test. He eagerly agreed, and I had a DNA kit sent to one of his sons in Memphis, who collected my uncle’s saliva. 23andMe has analyzed and calculated his results; they have been uploading some of the results this weekend. When I saw my uncle’s Ancestry Composition last night, my mouth dropped. I realized that I had jumped to a wrong conclusion in 2013, shortly after getting my mother’s 23andMe results. I even wrote an entire blog post on this wrong assumption.

When I wrote “DNA Found Native Americans Resting in Family Tree” in August 2013, I was largely confident that the huge Native American segment on my mother’s X chromosome came from her paternal grandmother, Sarah Partee Reed (1852-1923). My aunt (mother’s sister) and I also have large Native American segments on our X chromosomes. See diagrams below. You see, family elders had relayed that Grandma Sarah had some Native American ancestry. I even presented some circumstantial evidence of this alleged Native American ancestry in that blog post. Since 50% of a female’s X-DNA comes from her paternal grandmother, I wasn’t totally off-based from concluding this, right? But, I overlooked where the other 50% of my mother and aunt’s X-DNA come from because it appeared that I had DNA proof of my family elders’ Native American claim. That would have been major. Nonetheless, my elders’ Native American claim may still be accurate, but the huge Native American segments on our X-chromosomes definitely did not come from Grandma Sarah Partee Reed.

Below is a snapshot of the ancestry composition of my uncle’s X-chromosome. To my surprise, a vast majority (over 80%) of his X-DNA is of Native American ancestry! His ancestry composition includes 2.0% Native American, and most of it is on his X chromosome. Another small chunk falls on his chromosome 7. A man inherits all of his X-DNA from his mother, while 50% of a female’s X-DNA comes from her mother and the other 50% come from her father’s mother. Therefore, the Native American ancestry on my, my Mom, and her siblings’ X chromosomes came from their mother, my maternal grandmother.


(1) The ancestry composition of my Uncle’s X chromosome

 (2) The ancestry composition of my Mom’s X-chromosome


(3) The ancestry composition of my Aunt’s X-chromosome


(4) The ancestry composition of my X-chromosome


(5) X-chromosome triangulation in 23andMe: My uncle compared to my mother (green), my aunt (blue) and me (purple). My match to my uncle on the X chromosome is my Native American segment (69-115 Mbp, 33.9 cM, 3297 SNPs)

With my uncle’s DNA results, and utilizing the male X inheritance chart, I can now pinpoint which of my maternal grandmother’s ancestors could and could not have passed down these large Native American segments on our X. One of these five great-great-great-grandparents passed it down, along with the average percentage of X-DNA that my uncle can inherit from them. However, from each of these five Mississippi ancestors, my uncle could inherit as little as 0% or as much as 100%.

1.    Wade Milam (born c. 1820 in Alabama): 25%
2.    Margaret “Peggy” Warren Milam (born c. 1829 in Tennessee): 25%
3.    Unknown mother of Edward Danner (probably born c. 1800 in So. Carolina): 25%
4.    Elijah Wilbourn Jr. (born 1810 in So. Carolina): 12.5% (He was white.)
5.    Clarissa Bobo (born c. 1823 in So. Carolina): 12.5%

Now I wonder if Cousin Robert Danner (1905-2008), my maternal grandmother’s first cousin, was right after all. He was a walking history book! You see, when I first interviewed him in 1996, he showed me the following picture of his paternal grandmother, my great-great-grandmother, Louisa “Lue” Bobo Danner (daughter of Clarissa Bobo). I immediately asked him if she had Native American ancestry. Other family members had shared with me that she was half Native American, while my mother and other family members had shared that she was half white. There was obvious confusion about her ancestral background.

Well, Cousin Robert confirmed her white paternity, and he was even able to provide the name of Grandma Lue’s white father, Elijah Wilbourn, and a white half-brother called Sandy Wilbourn. Hear his interview here. A solid 4th cousin DNA match in FTDNA between my mother’s second cousin Orien (another great-granddaughter of Grandma Lue) and a great-great-grandson of Elijah’s brother seems to suggest that this paternity claim is accurate. With my eyes fixated on Grandma Lue’s picture, I then asked if maybe Grandma Lue’s mother (Clarissa Bobo) may have had Native American ancestry. Cousin Robert expressed that he never heard anything about that. However, he relayed that his father told him that his grandfather’s people back in South Carolina were considered “Black Indians.” Therefore, the alleged Native American ancestry was via my great-great-grandfather, Edward Danner. For some reason, I ignored that claim about Grandpa Edward Danner and had deemed it as being one of those “Indian myths”. Now my uncle’s DNA results have me wondering. Hmmmmm………


My great-great-grandmother, Louisa “Lue” Bobo Danner (1842-1921)


My maternal grandmother, Minnie Davis Reed (1908-1971), around 5 years old, with her mother, Mary Danner Davis (1867-1932). She was Grandma Mary’s youngest child of nine children.

4 comments:

  1. Always interesting and thought provoking.

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  2. Indeed, a timely, useful research reference. THANKS!

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  3. Wishing I had some uncles left to test.

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  4. X DNA is very interesting! I have 3 generations tested and by comparing our X's, it appears that my son (I am female) inherited my father's X at nearly 100%. My mother's X is almost 100% European and my fathers is African. So it is easy to see my father's X, the X that I got from him, and the X my son got from me...all appear to be exactly the same!

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