Tuesday, December 26, 2017

Hidden DNA at Ancestry

A couple of months ago Ancestry made another change to their policies for managing DNA test results. It is a mix of both good and bad, depending on your perspective. You can choose to hide your test from your DNA matches. If you make that choice, you also can’t see your matches. If you have extreme privacy concerns, this change could be a blessing. However, you could also skip the test or choose to delete the test from Ancestry. So this change feels a bit ridiculous.

It seems a lot of people merely want their ethnicity results, but not matches. If they choose to hide their results, they will disappear from our match lists. That would help reduce the wasteland of useless results that we researchers must wade through.

However, sometimes even a match without a tree can help with a breakthrough. I’ve assisted a couple of adoptees who relate to tests I administer, with skeleton trees that are private. I recently received a nice thank you from such a researcher who identified her birth grandfather after I shared just a little information.

I also had a personal victory. Over a year ago Roberta asked on the DNAExplained blog about converting a New Ancestor Discovery into an actual ancestor. I was able to do that recently with the help of a treeless match. It did take a lot of lucky breaks.

I administer a test for a college student that I’ll call Missy. Her parents divorced when she was young and her father poisoned the relationship by casting doubt on Missy’s parentage. His French-Canadian Catholic family was not pleased with Missy's mother. Conversely, her mother’s family, including me, was incensed at his behavior.

I tested Missy simply as part of testing many family members. Ironically, her DNA is more heavily French-Canadian than her older sibling’s. She has 12 new ancestor discoveries — more than anyone else among my 11 family tests — and most of those discoveries are French-Canadian.

For several years I have been blocked at Missy’s living paternal grandmother. Let’s call her Grandma Case (as in case study). I knew her birth date and her maiden and married names, but could not identify her parents. I also needed to do this work without reaching out to other Case researchers.

One of Missy’s New Ancestor Discoveries has the Case surname and was born in the Montreal area in about 1799. This looked like a good hint, but I was not interested in spending the time to do a descendants study.

Missy has a close DNA match with no tree, but with 329 centimorgans shared across 14 DNA segments. Lucky break number one.

The man we’ll call Eddy Case used his real name when he registered his DNA test. Lucky break number two. I waited for a year to see if Eddy would provide a tree, but it didn’t appear. One day, when reviewing the new ancestor discoveries, I decided to see if it was possible to break through the brick wall with just the information I had.

A Google search on Eddy’s name turned up only four matches in the entire US. Lucky break number three. Too many matches would have put a quick stop to the research.

One of the four men lived in the right area of Michigan. He had been interviewed in a newspaper article, giving his age. Lucky break number four.

Eddy was born before the 1940 census. Lucky break number five.

Starting from the 1940 census, I quickly ran up his tree and arrived at the new ancestor discovery couple. All the work to this point would have been done for me if Eddy had posted a tree. So this part of the journey is not a show-stopper when working with a promising NAND.

The next step was to determine possible relationships between Grandma Case and Eddy Case. One of my considerations needed to be the fact that the French-Canadian community is endogamous, which can make the match stronger than it might otherwise be.

Blaine Bettinger at The Genetic Genealogist has researched how DNA match strength corresponds to relationships. He has posted a PDF with several handy charts at his website and he updates it periodically. He has clustered relationships by strength and provides tips about how to determine probable relationships. He also tracks endogamy in his collected information.

From the charts, I could see that the match between Eddy and Missy falls into clusters 4 or 5. Grandma Case could be a younger half-sister to Eddy, a first cousin, a niece, or some other relative within two generations.


The next step was to document Eddy’s siblings and cousins. Missy had no matches to anyone in Eddy’s mothers family,  but had a number of matches related via Eddy’s grandmother’s family. I decided to ignore the possibility that Eddy was a half-sibling to Grandma Case and focus instead on Eddy's first cousins.

Tracing Eddy’s aunts and uncles, I ran into a number of roadblocks but was able to eliminate most branches through obituaries or early deaths. Finally, when ready to give up with three open branches, I found an obituary on an obscure website that listed Grandma Case as a daughter of the deceased. Lucky break number six.

Grandma Case was indeed a younger first cousin to Eddy, making Missy a 1C2R to Eddy, which is a cluster 5 match.

Would I have eventually made the find without Eddy’s DNA match? The close match with a clear name and the wonderful relationship chart led me to the right branch. If Eddy chooses now to hide his DNA tests from his matches, someone else may not have the hint they need to make a discovery.

The entire project was completed in one weekend. That is fast in genealogy time! So thank you, Eddy Case, for your contribution.

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