Breaking an Irish Brick Wall with DNA
Updated: Feb 25, 2022
Happy Labor Day! I am happy to say that it appears that we dodged Hurricane Dorian here on the west coast of Florida. We spent time last week preparing and as the track of the storm moved east, we moved out of the threat area. Of course there appears to be 2 or 3 additional storms out in the Atlantic, so we need to stay vigilant. That's hurricane season in Florida. Just hope nothing hits near October 2nd when I leave for Ireland!
I wrote a pretty complete blog on Occupations for Labor Day last year, (if you're new, I'd encourage you to go back and read it) so I'm going to stick to the DNA topic. Last week's blog readership jumped to over a thousand readers, so it appears to be of interest.😀
As I've said in the past, I don’t consider myself an expert on DNA…I’m on the journey and still learning. I’m sure there are many readers who are much more advanced on this topic and if you are interested in sharing that expertise as it applies to your Irish research, or if you have a success story you’d like to share, please feel free to contact me about writing a guest blog or add your experience in the Comments section.
I tested originally at 23&Me back in 2009, but mainly for health reasons. I have always been very interested in health history and how genealogy can help provide information to family about health risks. Although 23&Me provided genealogy information, I didn’t pay much attention to it. There were lots of names, which I didn’t recognize and when I tried to contact the closest ones, most didn’t respond or if they did, like me they too had tested for health reasons. At all of the major conferences I would attend the lectures on DNA and leave more confused wondering why I would want to do this.
In my first blog on Where do I test, I discussed Y-DNA and how I met John “Jack” Moughty of County Longford. The shock for my husband, Brian, was how much Jack looked like his father, Bernard "Pat" Moughty, who had been dead for 12 years. (Jack is on the left and Bernard on the right.) Through the years I attempted to make the connection between the families, but was unsuccessful in connecting them. Here’s a chart created through traditional research.
The fact that I had been able to trace the family in County Longford back to the early 1800s was all about the time and place. Roman Catholic baptismal records in this area went back to 1820. So I was able to trace Brian back to Bernard born about 1814 and Jack back to Michael, born about 1816. But like most Irish researchers, I hit my brick wall. There were no records that would give me the parents of Bernard and Michael.
It was at this point that I decided to try a DNA test. I understood the basics of Y-DNA (father's, father's, father) and since both Brian and Jack carried the Moughty surname, it would at least tell me if they shared a common ancestor. Jack agreed, and so in 2014 I visited Jack in County Longford with a Y-DNA test in hand. I also tested Brian. The results showed that they had a common ancestor…no surprise, I could tell that from looking at them! But how far back was the common ancestor? They had a genetic distance of 1at 37 markers which meant they had a 50% chance of being related within four generations and a 95% chance of being related within 10 generations. The good news was they had a common ancestor...the bad news was if it was 10 generations back, I wasn't going to solve this brick wall in Ireland!
The breakthrough for me on DNA was taking the Virtual Institute class on autosomal DNA with Blaine Bettinger. The lightbulb finally went off, and I realized that an atDNA test would give me the approximate relationship based on the amount of DNA Jack and Brian shared. Since the Y-DNA test had been with FamilyTree DNA I was able to simply upgrade it to atDNA. The results showed 53cM (centimorgans) of shared DNA and estimated at 3rd-5th cousins. A check of the ISOGG* Average Shared DNA chart showed 53 cM as likely 3rd cousins or 2nd cousins twice removed. Since I initially did this, Blaine has developed a Shared Centimorgan Project Tool. He asked genealogists to provide cM information on known relationships which he compiled to show the lowest and highest cM counts for various relationships, along with the averages. Since these numbers can vary widely based on the process of recombination, Blaine's tool shows lots of possible relationships, rather than just 1st, 2nd, 3rd cousin, etc. Here's what it looks like for 53cM.
That's a lot of different relationships! Based on the paper trail, I could pretty much rule out 1st or 2nd cousins. And since Brian and Jack were in different generations they had to be once removed. The chart showed that 3rd Cousins once removed shared between 0-173 cM with the average being 48cM, pretty close to my 53cM. The likelihood therefore is that I am one generation away from the common ancestor. Now what?
I’ll finish the story next week and show how Cluster Research provided a potential solution.
*ISOGG - International Society of Genetic Genealogists - check out their WIKI. This site contains an extensive amount of information on Genetic Genealogy.
The Virtual Institute is no longer available, but you can follow Blaine on Facebook where he is the administrator for numerous pages; on his website, The Genetic Genealogist; as a contributor to The Genealogy Guys Podcast or join his membership site, DNA Central. Here's a link (below) to the 2nd edition of Blaine's book, The Family Tree Guide to DNA, just published in August. (Note: the link to the Kindle version is to the old 2016 version of the book.)
You can check out links to DNA resources here.
Registration is open for the 2020 Ireland Research Trips.