Relationship Estimates

Every story has a beginning and every journey has a first step. But right before that there is a pivotal moment. Breath is exhaled and destinies defined. That moment of breath is part of my story. It is also part of my journey into knowing from whence I came. It all started standing at the foot of the grave of my 3rd great-grandparents, Archibald Sinclair and Ann McVean.

I don’t recall the first time I accompanied my granny to the cemetery. Or even the first time we placed flowers at this beautiful red granite headstone. I only know I’ve been doing so for more years than I can remember. The last internment in this lair was before my parents married, let alone I was born. While I personally knew none of the souls who rest here, the pull of connection is strong. Maybe there is a word for this in Gaelic, but that is beyond my language skills.

I feel I have come full circle.  My exhale became an inhale and I was rejuvenated. Years of searching dusty documents and tracing down hints across the ocean paid off. Today, I received the results for a DNA test kit I administer for my mother’s first cousin.  Score! Iain matches a known cousin in Canada.  The most recent common ancestors are Archibald Sinclair and his wife Ann McVean. So this thrills me beyond description.  It feels like a little bit of Archie and Annie reached out from beyond the veil and touched a little bit of my core.

Testing company estimates vs. cM measurements

At 15.6 centimorgans (cM) of shared DNA over 2 segments, it really is a little bit. Ancestry estimates the relationship between Cousin Iain, and the match, my mother’s 3rd cousin, as distant. They suggest somewhere in the 5th-8th cousin range.  In actuality, the connection is one of third cousins. This is a prime example of why we shouldn’t use the relationship estimates by the testing companies. Rather, we must calculate the possible relationships using charts such as Blaine Bettinger’s Shared cM Project.

Blaine’s chart puts the range of shared DNA for a 3rd cousin in the range of 0-198 cM, with an average of 79 cM. Consequently I’d have guessed the relationship was in the range of 4th cousin 2 generations removed, as the average shared cM is 14.  However, as Blaine keeps telling us – you have to look at the range!

Check out Kitty Cooper’s great blog post on this same subject.

Red granite headstone in Dunoon Cemetery

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