Monday, April 20, 2015

A DNA Update

The Lacey family tree, beginning with my grandfather, David Austin Lacey


When I last wrote about my family's foray into DNA testing, we had a real mystery on our hands.  My father had done a 67-marker Y-DNA test and the results were quite unexpected.  Rather than connecting him with Lacey relatives, it indicated that most of his close matches bore the surname Elliott. 

As explained in my previous post, Y-DNA traces the patrilineal line.  The Y chromosome is passed down, unchanged, from father to son. When my father's results indicated no connection to anyone else with the surname Lacey, he was very surprised.  How could this be?  We put our heads together and tried to come up with possible explanations.

The first thing my father did was upgrade his test.  He had initially tested on 67 markers and this had revealed a number of matches with a genetic distance of 0 to 3.  A Y-DNA 67 marker match with a distance of 0 gives you about a 95% probability of having a common ancestor within the last 150-200 years or about five generations.  We are confident about the Lacey family line back until about the year 1800, so this was extremely puzzling.  We thought we could get some more clarity on these results by testing my father on 111 markers.  This is the most thorough Y-DNA test you can do right now and would provide a more accurate timetable for the most recent common ancestor shared with his matches.

When the Y-DNA 111 marker results arrived, it still showed that my father was a match to Elliott men, not Lacey men, but it gave us a better understanding of the situation.  Matches that had been reported as having a genetic distance of 0-3 with the 67 marker test now had a genetic distance of 5 or more.  As popular testing company FamilyTreeDNA explains it, a genetic distance of 5 on a 111 marker test "indicates a genealogical relationship [as opposed to a close relationship]. Most matches at this level are related as 12th cousins or more recently, and over half will be 7th cousins or closer."

It seems that somewhere back in the family tree, one of my father's direct male ancestors was a Scottish Elliott, not an Irish Lacey.  There are so many reasons this might have happened (infidelity, rape, adoption, etc.) and we may never know that complete story.  However, we now have a better understanding of when this event occurred.  The matches provided by the 111 marker test indicate that the common Elliott ancestor lived in the 1700s or earlier, well beyond our knowledge of this family line.

This means that all of my father's known ancestors are still his ancestors.  The Elliott intermingling happened before our family history paper trail starts. So, my father is still a Lacey and he is still Irish.  It's just that genetically, his deeper roots are different than he thought they were. 

We're having fun reading about the Elliotts and their history.  Ironically, I already knew a bit about this family, since my mother's ancestors are Rutherfurds, and the Rutherfurds and Elliotts were neighbors on the Scottish-English border.  In fact, at least one Elliott married into my mother's Rutherfurd family.  My parents find this connection amusing.

The Lacey ancestral home (Rossadillisk, Ireland) and the Elliott ancestral home (Roxburgh, Scotland)

In the early seventeenth century, a number of Scottish Elliotts migrated to what is now Northern Ireland.  They clustered primarily in County Fermanagh, although some families ended up in County Donegal and other areas in the north. This at least brings the Elliotts to the same island as the Laceys, although County Fermanagh and western County Galway are not all that close.  Sometime in the 150-200 years that followed, Elliott DNA ended up in Rossadilisk amongst the Laceys.  I don't know if we'll ever be able to determine the circumstances of this event, but DNA may eventually help to connect us with a specific line of Elliotts.  We'll keep working on that.


2 comments:

  1. This is really fascinating! Thank you for sharing.

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  2. Thank you, Michelle! DNA has added such an interesting component to our genealogical research.

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