Secondary Genealogical and Genetic Lines

When we find an autosomal match in genetic genealogy, and we then discover that person shares a common ancestral line with us, we do our happy dance and  tend to forget that they might actually share a second line as well.

It’s easy to discount in the excitement of the moment, especially if you’re working in a situation where your match to that ancestral line on that segment has not been proven by triangulation.

But let’s face it, all genetic genealogy success stories, whether just one to one matches or triangulation begin with individual matches.

So, I was curious, just how many of our matches really do share a secondary genealogy line.

Now, let’s be very clear here about what a secondary line is, and is not.

This is my father’s pedigree chart.

father's pedigreeLet’s say that I find a match who shares the bottom center couple – Samuel Claxton and Elizabeth Speaks.

They automatically share the lines to the right of those ancestors in the pedigree chart – those who contribute to the DNA of Samuel and Elizabeth.  In this case, that would be Fairwick Claxton, Agnes Muncy, Charles Speak and Ann McKee.

As we move the pedigree chart out further in time – that list of common ancestors that we do share would include everyone on this chart including and beneath the blue cell, James Lee Claxton.  These are NOT secondary lines, just ancestors of the people in the original match that we would also expect to have received some amount of DNA contribution from.

father's pedigree 2

Now, let’s say we start looking at the tree of the person we match and we discover that they also share the top center ancestors, Henry Bolton and Nancy Mann.

father's pedigree 3

That is a secondary line, not connected genetically to the first line.

Obviously, if the person we match has ancestors living in the same geography as our ancestors, there’s a possibility that they will share a second (or even third) ancestral line.

How often does that actually happen?

I’ve been working with my shakey leaf matches at Ancestry.com.  Shakey leaf DNA matches are those with whom Ancestry has identified that you have a DNA match and a common ancestor in a tree.  I love shakey leaves!!!!  They save me so much work.

shakey leaf

Now, the easy assumption to make is that your DNA match is through the ancestor noted on the tree.  That’s certainly possible, and if that is your only common ancestor, it’s even probable – but without a chromosome browser and triangulation there is NO PROOF.

There is no way at Ancestry to prove a genetic relationship.  But that doesn’t mean you shouldn’t gather evidence.

I’ve been keeping a spreadsheet of matches at Ancestry, our common ancestor, which child they descend from and any other known common lines.

ancestry match spreadsheet

I have a total of 137 rows, each representing a shakey leaf match at Ancestry.com.

Of those, 16 disappeared with Ancestry’s new phasing rollout in November.  No, I am not “over that”…nor do I think it’s accurate because I match some of those same people elsewhere and triangulate with common ancestors.  Nuff said about that – no point in beating a dead horse.

Recently, Ancestry has added a feature that allows a hint to additional shared ancestors.  However, on mine, which is all I can really address, all of my multiple hints were to people in the same line where Ancestry appears to have been confused, perhaps by people’s trees.

For example, the three hints on the match below includes one, as shown, one to only the mother (Suzanna Berchtol) and one to their grandson’s wife’s mother (but not her father.)  But there was no match to the son and his wife.  These are not inaccurate, just confusing.

multiple hints

None of my multiple hints were actually to different lineages – although several matches’ trees do exist that include unquestionable matching to multiple lines.

Ancestry includes a great comparison feature.

If you view your shakey leaf match, they show you the common ancestor of both individuals in a tree, as show below with cousin Harold.

common surnames

If you scroll down, you will see the list of common surnames we share – in the green box on the left.

Because I know my own tree quite well, along with cousin Harold’s, I know by just looking at this list that all of these except one are from the same line as Joel Vannoy and Phoebe Crumley, our common ancestors.

But, for purposes of example, let’s say that I discover one that isn’t.

Let’s say Mercer isn’t a name from our known common line.

common surname compare

By clicking on Mercer, you can see that yes, indeed, we do share a common ancestor.  Hannah Mercer appears recognizably the same in both trees.

Looks like cousin Harold has more Mercers than I do, so I need to visit with cousin Harold about this.

Now let’s look at Webb, our name that is not from this common line.

common surname compare 2

Webb doesn’t match.  Furthermore, I haven’t entered anything about this person that even remotely identifies them, so I need to address that.  Even approximations are useful, and no information at all is not useful.

I went through this process for every single common surname for each tree that I match.  Of interest, there were only a few trees that didn’t have any surnames that I needed to check.

On top of the matches I lost through phasing, we need to subtract another 21 for private trees and one more because their tree won’t load due to a technical issue of some sort.  Of the 21 private trees, I have written to all 21, and 4 of the individuals answered me by telling me the name of our common ancestor.  However, that still does not provide me with the ability to see this page that shows our common matching surnames.

That leaves me with 99 shakey leaf matches whose trees I can see.

Of those, 52 do not have a common ancestor or a common line that makes me think we might have a common ancestor.  What the heck does that mean?

It means that roughly half of my matches either do or might have a secondary matching line.

Let me give you a couple of examples that make it difficult to decide.

Campbell – those darned Campbells.  First, I’m at a dead end with mine in Hawkins County, TN around 1800.  We do have a Y DNA representative from my line though, and we know that our Campbell line matches the Campbell clan line.  So, anyone where I see Campbell in their surname list, regardless of how far back in time that Campbell link goes – I categorize as “possibly Campbell.”  Because, frankly, we not only don’t know for sure how long that sticky DNA can stick together and I don’t know which line my Campbells descend from in 1700s Virginia, assuming that is where they came from.

Secondly, Hall.  My Hall family was from Tolland County, CT.  When I see someone else’s tree that shows a Hall ancestor from Tolland County, CT, even though they don’t connect with mine – I know darned good and well there is a very high likelihood that this is the same Hall family as mine.  So, I categorize that as “probably Hall.”

When I find a dead hit in terms of a common ancestor, I just enter their name in that column

I have 4 that I’ve categorized as “not recognizable” which means to me that it looks quite suspicious in terms of surname/geography, but no smoking gun like Hall in Tolland County.  I’m combining these with the “no” group for now, understanding that a “no” could turn into a “yes” with a breakthrough for anyone at any minute.

I have 13 labeled “possible.”

I have 7 labeled “probable” but ironically, two of those have two lines each that are not connected to each other.

I have 8 that are Acadian, meaning they descend from a large group of common surnames from the Acadian community.  This is a highly endogamous community and it’s nearly impossible to tell which DNA comes from where and originally belonged to whom.  This means that lines on my chart that appear to be disconnected probably are not.  I view these as all “yes” in terms of multiple lines.

I have 15 matches with positively confirmed secondary lines, and of those, another 5 possible third lines.

So how does this stack up:

No Possibly Probably Acadian Yes-Confirmed >2 lines
% Matches 56 13 7 8 15 10 + 8 Acadians

Truthfully, this is far more than I expected.  I thought it would be the rare match where I would have two disconnected genealogical lines.  In reality, it appears that it could be about half the time.  This certainly causes me to take a moment to pause and reflect – and makes triangulation even more important.

What this really means is that we cannot assume that DNA/Tree matches are connecting the dots between the right genetic lines and the right pedigree lines in a tree – because about half of the time, it could be the wrong line in our and their tree.  And this little experiment, by the way, cannot take into account the dead ends on either my tree or theirs that can’t be accounted for.

Let’s be very clear about this.  You DO share DNA with this person from a common genealogical line.  You MAY share DNA with this person from multiple lines.  The DNA may NOT have come down to you from both (or multiple) lines. From tools we have at Ancestry, we can’t tell which line or lines contributed the DNA.

The only way to prove a match is to a specific ancestral line is to triangulate the match, meaning that the same segment of DNA matches between a minimum of three people who share the same ancestor.  To do this, you need a chromosome browser, which Ancestry does not and says they won’t provide.

More and more Ancestry customers are transferring their results to Family Tree DNA and to GedMatch to take advantage multiple pools and tools.  So, you can’t prove a relationship at Ancestry, but there is still a lot of useful work that you can do based on your matches trees…so long as you don’t need proof.  In the next few days, we’ll be talking about how to maximize your AncestryDNA experience.

17 thoughts on “Secondary Genealogical and Genetic Lines

  1. I have received 357 new tree matches so far in January. As usual, about 50% are locked, or have no tree. I was receiving more than double that each month, but this is more manageable. Yes, it is a shame they do not provide a chromo browser………..and shocking that they can get away with their attitude re this crucial need of their customers.

  2. I have yet to receive a single shaky leaf hint on my Ancestry DNA. In fact very few of my matches even show a family tree. Almost no one shows a real name. its all initials and code names.That leaves few options other than contacting someone who is a relatively close (2nd -4th is the highest I show) through Ancestry and hope they respond.

    I cross loaded my Ancestry results to FTDNA and in addition to their being much better tools there I can see real names and real email addresses. I can then look up the emails on GedMatch to extract even more info. Why do the people on Ancestry seem to want to hide rather than share information?

  3. Wow, 112 shared ancestor hints! That certainly blows away my mom’s paltry 20, my brother’s whopping 21 and my 38. (I don’t think there is a “genealogy gene” in my ancestral tree.)

    I’ve moved mine and mom’s over to FamilyTree DNA (my dad’s is already there), but I haven’t had much luck convincing anyone from our matches to make the move with us.

  4. Roberta, I’ve been hoping you’d cover something similar to what you’ve written today on multiple lines–specifically, the possible effect on autosomal results (centiMorgans) from the incidence of intermarriages. In this case, two people are related multiple times specifically because two or more people from the same line married into that line again, i.e. cousins marrying cousins, then repeated scenario one or two generations later.

    The reason I ask is that I have just found a match on one surname line, which we have calculated to be eighth cousins, twice removed. However, the size of the centiMorgan measurement, the number of segments we share in common, and the length of those segments seem to suggest a closer relationship than that. The testing company (Family Tree DNA) estimated our relationship would be around fourth cousin level. Could intermarriages–several generations back–amplify the cM results for us to more than the relationship we anticipated, based solely on the paper trail? We’ve checked for multiple relationships, but there seem to be no other surname lines–your multiple lines example–to pin this number anomaly on.

  5. Roberta,

    Thanks for addressing techniques for evaluating Ancestry matches, I look forward to upcoming discussions. I have, in the past, taken advantage of the shaky leafs and DNA Circles in order to convince my suspected matches to upload data to gedmatch.com where comparisons can be made.

    I noticed that the ancestral chart (fishbone) at the beginning of the blog had generation headers at the top. Was this generated by your home genealogical program? If so what do you use.

    Thanks again

      • Roberta,
        I thought I recognized the old reliable PAF. Hahahaha! I’m hooked on it too. My wife and I taught PAF in the Training Zone in 2011-2012 and supported the software in the Worldwide Support Zone of the LDS Church in 2007-2008 when we served in the LDS Family History Department those years. I began using PAF v.2.2 in July 1990. According to my journal, my data was stored on a 5-1/4″ 360K floppy disk. They stopped updating PAF in 2002. Support for it was cancelled in 2013 (see https://familysearch.org/paf).

        I finally switched to Roots Magic then. I’ve had Roots Magic for years but never used it. Also have Legacy, Family Tree Maker, and Ancestral Quest (can you tell I’m a genealogy software junkie). They’re all good but PAF was a work of art thanks to Gaylon Findlay who created the first Windows version. It was fun working with some of PAF’s original designers in Salt Lake City when we lived there in 2007. I finally got to meet Gaylon in 2008 at a BYU Family History Conference. He still offers Ancestral Quest, a more powerful PAF look-alike.

        You must know that stand alone computer genealogy software is now a thing of the past. Only us old timers still use it. Almost all the youngest who are attracted to family history these days use online databases such as FamilySearch.org’s Family Tree, Wikitree.com, or Ancestry.com. At least that’s been the case with the ones I’ve taught lately. I see people using their tablet PCs or even their smart phones to access their genealogy. I have those too but nothing, in my opinion, will ever compare to the simplicity and ease of use of PAF. I still use it from time to time.

        Ron.V

      • Now this is kind of funny, because I have Legacy sitting here along with RootsMagic too. I think I prefer RootsMagic and I know that I will need to actually start USING it at somepoint:) I just haven’t seen the need to yet. The only things PAF didn’t do that I wanted it to, PAF Companion did.

  6. Pingback: Friday Finds – 01/30/15

  7. Thanks for this post. I am one of those taking advantage of FTDNA and GEDmatch. It’s opened up access to matches in countries like Finland, a place to which I can’t find any link to yet, but have several matches with. I have more shaky leaves than you can throw a stick at in ancestry.com and a few from which I could triangulate an ancestor in GEDmatch, but for the most part I haven’t been able to do much with the data. I’ve been looking for a way to wrangle the names and matches and like your spreadsheet layout. I’ll have to try it.

  8. Pingback: Getting the Most Out of AncestryDNA | DNAeXplained – Genetic Genealogy

  9. Pingback: Autosomal DNA Matching Confidence Spectrum | DNAeXplained – Genetic Genealogy

  10. Pingback: DNAeXplain Archives – Introductory DNA | DNAeXplained – Genetic Genealogy

  11. Pingback: The Ancestry 200 | DNAeXplained – Genetic Genealogy

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s