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Using DNA before you head to Ireland


Before you head to Ireland to research, you need to take a look at your DNA results. You haven’t taken a test yet? Now’s a great time to do it, as most of the DNA companies are offering special pricing (in time for St. Patrick’s Day). For those who aren't expert yet (and that includes me) here are some suggestions on how you can take your results and use them to identify matches in Ireland (or descendants of your Irish families).


If you tested at Ancestry, check out your DNA Story. Ancestry in some cases can identify DNA Communities from which you descend. Mine is primarily Scotland and Northern Ireland which matches pretty well with my paper research. My husband (see above) is 97% Irish and his results are broken down into various communities. If you don't know where in Ireland your ancestors were from, this can be helpful. His four grandparents emigrated from Ireland in the early part of the 20th century from Monaghan, Down, Mayo (on the border of Roscommon) and the border of Longford/Westmeath. His communities are very close to the paper trail. You can read about how Ancestry comes up with the percentages but be aware that these can go back hundreds of years.


You should move your results to all of the various DNA companies to play in the big pool, rather than just the smaller pool of your testing company. If you’ve tested at Ancestry, you can move your results to FamilyTree DNA, MyHeritage, Living DNA and GEDmatch. You cannot move your results to 23andme. Also, Ancestry does not accept results from other companies, so if you haven’t tested, consider testing first at Ancestry as they have the largest database. 23andme does not accept uploads from other companies so you should also consider testing there, especially if you are interested in health results. If you manage DNA results for other family members, ask for permission to move their results as well (you should never move results without permission). Over the past few years there has been lots of discussion of law enforcement’s use of various genealogy databases especially GEDmatch since their site was the first one identified as assisting law enforcement in the Golden State Killer case. For information on the policy of each of the genealogy companies, you should read Investigative genetic genealogy FAQs on the International Society of Genetic Genealogy (ISOGG) Wiki. No matter how you feel about this, you should know that at the present time, two companies, FamilyTree DNA and GEDmatch allow law enforcement matching under certain circumstances and with your approval. Everyone in the GEDmatch database is opted OUT of law enforcement matching unless you specifically opt in. The other company involved with law enforcement matching is FamilyTree DNA and in their case you need to specifically opt out by going to your Account Settings>Privacy and Sharing and selecting "opt out." In both cases you have a choice. There are lots of places where you can read in more detail about law enforcement's use of DNA, but I want to mention it, because both of these companies are important when using some of the Irish matching sites. Diahan Southard has a blog on DNA Testing, Law Enforcement Access and Privacy which she updates as changes occur.


FamilyTree DNA has a large presence in Ireland as they were one of the earliest companies to offer testing there. If you've done atDNA testing somewhere other than FamilyTree DNA you can move your results to their site. FamilyTree DNA is also the only site that provides Y-DNA and mtDNA testing and they offer lots of different projects, for surnames, geographic areas and specific Y-DNA and mtDNA projects. A Y-DNA test can help determine which Daly group your family is associated with. To do this you need to have a known male descendant with the appropriate surname. I've written over the past few months about my search for a male Johnston descendant (I haven't found one yet). From your results page at FamilyTree DNA, open your results and begin by selecting "My Projects" then "Join a Project." You can then search or browse the lists to see what might be the best project(s) for you.

Once you've joined a project, from your dashboard, select "Advanced Matches" then click on FamilyFinder. From the drop down menu select which project you want to match and click Run Report.


Over the past few years, the number of my matches specific to Northern Ireland has increased from 2 pages to 4 pages. I was hoping for some Johnston matches, but no luck so far. The matches range from 2nd-4th cousin ( the first match is a 3rd cousin who I tested) to 4th cousins. This Project is administered by the North of Ireland Family History Society and if you’re visiting the Belfast area, I recommend you go ahead and join this group. Martin McDowell, one of the administrators is an excellent resource for this Project.


You can join as many projects as are appropriate. In each case with Advanced Matches you are only being compared to other individuals who have also joined the project. The first benefit is that the people who have done this are interested...they're trying to find you, too. Second, even if you don't have a close match, it might isolate the geography to assist in your research.


If you are going to use these resources, I'd like to encourage you to make sure you have a basic tree uploaded or can refer people to your online tree. The example below is NOT helpful! All our research is based on time and place, so PLEASE add not only names of deceased individuals, but also dates and places (use estimates if you don't have the exact information).

Back to GEDmatch. There are multiple reasons why you want to have your results here. First, like FamilyTree DNA, people who placed their information here are interested in finding you. Second, it has a chromosome browser, so if you've tested at Ancestry (which doesn't have this feature) you can use DNAPainter (more on that in the future) or a chromosome browser at another site. And third, you can utilize the Matchmaker tool through Facebook Groups. For your Irish research, number three is the big winner! If you decide to do this, follow the posted directions for each group exactly. On my Links and Resources pages for the Counties you’ll find some of the listings. Not all Counties participate. This blog reminded me that I hadn’t posted in a while, and I received my first response in 4 minutes!


The first thing you need to do is request membership in the Facebook group you are interested in. Because of privacy concerns these are closed groups. It's simply a matter of filling out a request and answering a couple of questions. What is your GEDmatch number? (You can't join until you have transferred your DNA results to GEDmatch.) Where were your ancestors in that particular county? What surnames are you searching? The Administrator will check your answers and you'll receive a notification that your request has been approved.


Next you open the Matchmaker tool (which is a Google Docs Spreadsheet) and make a copy. Go to your GEDmatch account and run the "One to Many DNA Comparison" not the Beta. Select and copy the entire page, and return to the Matchmaker tool and paste. The instructions are in the spreadsheet. Give it some time. It will paste in the results and then match them with others on that site and give you a list of your matches (if you continue to see the instruction overlay your spreadsheet, it's not finished yet...keep waiting).

The above image is what the spreadsheet looks like. After you select your entire GEDmatch spreadsheet (including text and titles) you come back here and paste. You don't select any cell just paste. The spreadsheet knows what to do! Even if you have hundreds of matches when it's finished you'll only have a list of the matches with other people in that Matchmaker set. I did this at Irish DNA. You can do this for multiple sites but each time start from the beginning...you don't reuse the spreadsheet from another site. Check the Links and Resources tab on my website for Counties to see if there is a DNA site.

The final step is a Facebook post. Copy your results from the Matchmaker results, and then tag all of the individuals by Facebook name. The last step is very important. Unless you tag the individuals they will not know they have a match. I don't go out to all of the sites on a regular basis. I only check when I receive a tag.


Here are some other suggestions. Don't bother tagging individuals with less than 10 cM. Someone with a 15 cM match is almost 5 generations removed. It's pretty hard to get back 5 generations on many Irish lines. You'll get a flurry of activity initially, then it will fall off. Re-run your matches every so often as new people are being added all the time. Keep track of your responses and only post new matches. This is also a time to point out how important it is to research all your collateral lines. That will give you the possibility of recognizing a name.


So that's a few additional ways to use your DNA results that focus specifically on your Irish ancestors. If you haven't already done so, I hope you have a chance to try them out. Leave a comment on your experience.


Happy Hunting!



If you've been following the blogs on researching in Ireland why not plan your trip for

October of 2022. There are still some spaces available.





Ends March 17th



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