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Serendipity strikes again

So the semi-annual meeting of the Board of Trustees of the Board for Certification of Genealogists® is underway in Salt Lake City and, as is the BCG custom, Board-certified genealogists donated their time yesterday to offer free lectures to the genealogical community.

Held in the Family History Library (FHL), the lectures are — first and foremost — BCG’s way to say thank you to the FHL and its staff for everything they do for us year in and year out. By sharing our knowledge with them, we hope to repay to some degree the many times they have shared their knowledge with us and with all genealogists everywhere.

The Legal Genealogist had the privilege of being the lead-off lecturer, doing a reprise of a topic I presented at the National Genealogical Society conference in Richmond in May: Shootout at the Rhododendron Lodge: Reconstructing Life-Changing Events.

It’s a presentation I dearly love, for many reasons: it’s got a great story — a firefight between good guys and bad guys in which the Bath County, Virginia, sheriff was shot to death; it’s got a lot of twists and turns — demonstrating why reasonably exhaustive research is so key to excellence in genealogy; and it’s a story where — if the shootout had ended just a little differently — my family would be so very different today.

Because, you see, when that sheriff set out that night in December 1929 to track down the men who’d been involved in a bar fight, he didn’t go off alone. He had picked a local man to back him up, had deputized him on the spot… and that local man was right in the middle of the gunfight that broke out when the two groups met in the darkness.

The on-the-spot deputy — who survived the night’s gunfight — went on to marry and have children, grandchildren and great grandchildren.

One of those grandchildren is my brother-in-law Mike, husband of my youngest sister. And two of those great grandchildren are my nephew and niece, Thomas and Rose.

It almost would have been enough genealogical serendipity that the lecture was yesterday, which happened to be my niece Rose’s birthday. Kind of cool to be talking about her great grandfather while she’s celebrating with her Dad.

But that was barely the start of it.

In the audience yesterday was another man named Mike. He’s a Facebook friend, a fellow genealogist, and one who has exactly the same Scottish last name as my brother-in-law. It had occurred to me once or twice in passing that I should ask this Mike if he’d ever thought about doing DNA testing; it would be fun, I thought, to see how Mike and Mike matched up.

I had the chance to ask that question yesterday and got one whale of a surprise for an answer.

Mike in the audience — call him MikeA — and Mike my brother-in-law — call him MikeB — are cousins.

Close cousins.

Where it counts.

In their genes.

Here’s the 12-marker YDNA match-up between MikeA (on the bottom) and MikeB (on the top):


They’re both in what’s called the Western Atlantic Modal Haplogroup: “the most frequently occurring 12-marker Y chromosome haplotype associated with haplogroup R1b1a2.”1 In other words, they’re both absolutely typical men of European ancestry.2

Now at 12 markers, there’s not a whole lot more than could be said. At 12 markers, an exact genetic match means the Mikes have a good chance — about 95% odds — of sharing a common ancestor within 29 generations.3 Give or take a few, figuring an average of 25 years per generation, that’s about 725 years. Not exactly within the usual genealogical time frame.

But neither of the Mikes stopped at 12 markers. Let’s look at the next set of 13 markers:


Oh, boy. So far so good — a 25-for-25 marker match, sharing a surname. That ups the odds quite a bit. With that kind of match, we’ve got a 95% chance of the Mikes sharing a common ancestor within 13 generations.4 Again figuring about 25 years per generation, about 325 years.

Better, for sure. But still pushing the limits of genealogical time. We think we know the original immigrant ancestor here, a man who died in late 1748 in Prince William County, Virginia. But wouldn’t it be nice to get even closer?

So… take a look at the next set of 12 markers — both Mikes have tested to the 37-marker level:


Oh yeah. A 37-for-37 marker match, sharing a surname.

The odds now? About a 95% chance that they share a common ancestor within seven generations5 — as little as perhaps 175 years. And the odds are about 90% that the common ancestor will turn up within five generations6 — roughly 125 years.

We’ve got our eyes on one particular man — a Loyalist — or one particular son of that Loyalist as likely candidates for the most recent common ancestor, and we’ve sure got some paper trail work to do to try to narrow down the odds.

But then there is that whole other set of odds. The odds that MikeA would be sitting there in the audience yesterday, listening to another part of the family story of his cousin, MikeB.

I can’t even begin to calculate that.

I love genetic genealogy… especially when serendipity strikes.


  1. ISOGG Wiki (, “Western Atlantic Modal Haplotype,” rev. 5 Mar 2014.
  2. What does the WAMH badge on my personal page mean?,” The Family Tree DNA Learning Center, Family Tree DNA ( : accessed 11 Oct 2014).
  3. Ibid., “Paternal Lineages, Y-DNA12.”
  4. Understanding Your Y-DNA25 Results,” Family Tree DNA ( : accessed 11 Oct 2014).
  5. Paternal Lineages, Y-DNA37,” The Family Tree DNA Learning Center, Family Tree DNA ( : accessed 11 Oct 2014).
  6. Ibid.
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