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Using DNA Shared Matches


I've spent the week doing additional collateral research on the Johnston family. I thought I was in good shape, but every time I take a look at a new record, something else pops up. If you haven’t done collateral research on the family you plan to research, jump to it! You never know what you’re going to find.

The person I’m trying to identify is the wife of James Johnston. I know that Margaret and Rachel are children of this couple and my hypothesis is that Eliza and William are also siblings. For this area, Rossinver Parish in County Leitrim there are no Church of Ireland baptismal records for this timeframe and Irish death records do not record the names of the parents. A family Bible might provide the information, if I can find it…it doesn’t appear to have passed down in my line (which descends from Rachel). Perhaps there is a family story that has passed down in another line.

I do know that James married a second time to Jane Johnston, and there was one child from this marriage, Matilda (Tilly) Johnston. So I need to do descendant research on the five individuals descended from James. Although Irish research is never easy, we are fortunate to have IrishGenealogy.ie (which is free). In my blog on December 13th, I explained how I created a marriage list for Johnstons beginning in 1845. Margaret, Rachel, Matilda and William are all identified in this list, all naming their father as James. If like me, you are researching females, this is important because the next step is to find the children of these marriages and for that, you need the married name. Yes, it takes some time, but we can research civil births, deaths and marriages from 1864 (and Protestant marriages from 1845). If your family was in an area where baptismal, marriage and burial records survive, you can move back using the church records.


Here are some blogs I’ve written about the process, for researching using these records, as well as collateral or cluster research.

Last week I ended the blog discussing Family Trees and DNA. I have some known cousins on the Johnston line. My best match to find a 3x great grandparent would be a 4th cousin and unfortunately, the ones I’ve found so far know little about their family. In addition to checking for matches at MyHeritage (which can be helpful for matches outside the US), I used Thrulines at Ancestry. I had 11 DNA matches that could be traced to James Johnston, my 3x great grandfather. Four of the matches were on my line, descended from Rachel…a 1st cousin, two 2nd cousins 1x removed and a second cousin 2x removed. I know all of these people and we’ve shared information.

The second group of matches are descended from Margaret Johnston, also with four matches. Although Thrulines shows them as “half” relationships, they are actually full relationships. (That pointed out to me that I need to update my DNA Tree, which I had uploaded in 2015. If you are wondering why this blog is late, that’s the reason!). I’ve spent the last few days identifying all of the descendants of Margaret using online trees (thanks to Diana and Deb), as well as hints on Ancestry. Margaret’s husband was John Curry and they had eight children. One died young, and I have been unable to find a marriage or death for the youngest daughter. Of the remaining six, two remained in Ireland and four emigrated to Bridgeport, Connecticut. I have identified 32 grandchildren, 12 great grandchildren and 5 great great grandchildren. Why is this important? Descendant research is important for identifying your DNA matches (see Diahan Southard’s website).

The third set of matches are from the second marriage of James and are to a known Half 4th Cousin. It's unlikely that this group of matches will know the name of James' first wife (my unknown 3x great grandmother) but the DNA matches may allow me to separate out those who are related through the second wife. The only problem I have here is that the second wife was also a Johnston, so there may be multiple relationships. This family also emigrated to Bridgeport, Connecticut. In each case I have looked at shared matches between me and the known cousin. I use Ancestry's "dots" and so I can mark all of our shared matches with a yellow dot. This should give me a list of potential descendants from James Johnston (in this case there were 21). The majority of them were 4th-6th cousins.

I’m continuing to work this plan so maybe something will pop in the next few weeks.

Happy Hunting and Stay Safe.







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