Introducing DNA Tidbits – DNA Tidbit #1: Triangulation

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I know this winter is going to be difficult, but don’t lose heart. I have a plan.

Covid is already spiking and many families have already canceled holiday plans. This situation, combined with the seasonal darkness and cold will make things even more difficult for people in the northern hemisphere. I’ve been trying to think of some way to help make things better, to lift our collective spirits – and I’ve come up with an idea.

Drum roll please…

Today, I’m introducing the first of what will be weekly “DNA Tidbits” – fun genealogy+DNA tasks that might, just might, reveal buried treasure.

You know, tidbits, as in those wonderful tiny little nuggets of luscious goodness that tide you over until you can eat the whole thing, whatever your “thing” is. No, wait…eat the whole thing – that’s not what I meant to say:) Tidbits are about pacing ourselves, right??!!

DNA Tidbits will be enjoyable to do together because we can share our findings. They will range from introductory to a little more complex so everyone can play, and learn.

We will be jumping around between different vendors and third-party tools, so this might be a good time to be sure you’re in the 4 major databases, FamilyTreeDNA, MyHeritage, Ancestry, and 23andMe, either by testing or by transfer, where possible.

Here’s a step-by-step article about how to transfer results to both FamilyTreeDNA and MyHeritage, which are the only two testing vendors that accept transfers:

DNA Tidbits

DNA tidbits will be different from my regular articles in that they aren’t going to be detailed educational lessons on HOW to do specific things. That’s already handled in lots of articles on my blog that are keyword searchable.

Keyword Searchable

For example, if you want to read about triangulation, what it is, and how to use triangulation at the various vendors, use the search box on the blog and type in “triangulation.”

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You’ll find educational and instructional articles along with other articles where I’ve mentioned triangulation, plus lots of examples.

DNA Tidbit #1 – Triangulation

A DNA Tidbit challenge will read something like this:

Challenge: Go to each of the three testing vendors, FamilyTreeDNA, MyHeritage, and 23andMe who provide triangulation, plus GedMatch. View your 5 highest matches that triangulate. Triangulation, of course, means that three people – you, a match plus someone else (not a direct relative meaning not parents or siblings) all match each other on the same segment.

Can you tell how the person or people you triangulate with match? Through which ancestral line? You might be able to discern this by viewing each triangulated match to see:

  • Who else they match in common with you. If they triangulate with you and your first cousin who you already know, that’s a huge hint as to the ancestral line.
  • Who else they match on that same segment.
  • Ancestors share by you and those matches. Look at their surnames, trees, and other tools to see if you can identify common ancestors.

How can or does this help your genealogy?

Have you painted those segments at DNAPainter? That’s yet another way to achieve triangulation.

Triangulation Instructions

When I’ve written articles about how to perform the various tasks referenced in a DNA Tidbit, I’ll include links to instructions.

Why is Ancestry missing from this list?

Because Ancestry doesn’t have a chromosome browser or triangulation, which is why checking at GedMatch is important. At least some Ancestry customers will upload their DNA files to GedMatch and not elsewhere.

Community

During these next few months when we won’t be able to see members of our own families, our genealogy community will be more important than ever. Be sure to post a comment sharing your outcome for each week’s Tidbit. Did you find something unexpected?

Trust me, you’ll inspire others and we all need positive inspiration right now!

This triangulation exercise is DNA Tidbit #1.

I’ll go first with a couple of examples to help you along the way. This is probably more detailed than future Tidbits because Tidbits are designed to be quick for you and me, both. Can’t do everything? That’s OK, do something.

There are no tidbit or chocolate police!

DNA Tidbit #1 – Triangulation Results

Family Tree DNA – My top 5 triangulated autosomal matches are people assigned to one parent or the other. That’s how triangulation occurs at Family Tree DNA. I’ve skipped the people whose relationships I’ve already identified, which I track by notes, and selected my top 5 that I haven’t previously identified. Their note icon is grey meaning nothing recorded there.

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Unfortunately, Christopher has uploaded no tree. He is, however, assigned to my paternal side with a sizeable piece of matching DNA across multiple segments.

Looking at who we match in common, I can discern immediately that we connect through my great-grandparents, Lazarus Estes and Elizabeth Vannoy because we match people who descend from both of those lines upstream of that couple.

Christopher and I match on three significant segments.

  • The first segment also matches a cousin who descends through Lazarus and Elizabeth.
  • The second segment matches a cousin who descends from the Campbell/Dodson line which is Lazarus Estes’s mother’s line.
  • The third segment matches a cousin who also descends through the Campbell line so this segment can be attributed to Elizabeth Campbell of the Elizabeth Campbell/Lazarus Dodson marriage. That means, in generational order, this segment descends to me through my father, his father William George Estes, his father Lazarus Estes, his mother Rutha Dodson, and her mother Elizabeth Campbell and her parents John Campbell and Jenny Dobkins.

Next, I viewed these matches in the chromosome browser of course, and in the matrix tool.

I made a note on the match at FamilyTreeDNA and painted these segments at DNA Painter, noting how I identified the segments.

Unfortunately, none of my top 5 triangulated matches had trees that were productive in terms of identifying a common ancestor.

Have you gotten this far? Good job. Eat a strawberry or chocolate tidbit.

MyHeritage – I chose Jason from my match list, the first person with whom I did not have a note indicating I’ve already worked with the match.

I reviewed the DNA match to see if Jason and I share triangulated segments with other people, indicated by the purple icon on my shared matches with Jason.

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Jason and I triangulate with my cousin Buster, which tells me that we share a common ancestor from either the Lazarus Estes or Elizabeth Vannoy lines, my paternal grandfather’s parents They are my most recent common ancestors with Buster.

However, as I scan on down the list of shared matches that Jason and I triangulate with, I see several people from my paternal grandmother’s side who do not share ancestors with my paternal grandfather’s side. My grandparents were not related to each other.

This indicates that Jason and I are related through two different lines that lived in the same area and intermarried.

I might need two pieces of chocolate for this one!

I need to send Jason a message. He doesn’t have a tree, but I bet he knows at least some of his genealogy since this connection seems to be within the past few generations based on the amount of DNA we share.

23andMe is more difficult because you can’t quickly see which matches have notes. Notes only appear after you’ve clicked on the match, and then at the very bottom of that page after scrolling to the end. Instead, I use the stars to indicate that I’ve worked with the match.

I click on the star to turn it yellow after I’ve analyzed a match, in addition to making notes.

My first match at 23andMe with no yellow star is RA.

Checking who I match in common with RA, I can see that 23andMe has assigned RA to my father’s side of my genetic tree, as a descendant of Lazarus Estes and Elizabeth Vannoy. Keep in mind that this tree is not uploaded, but genetically created by 23andMe with the customer adding the appropriate names of their ancestors in their proper position. This relationship tree can be incorrect, but it’s certainly a useful tool.

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Clicking “Find Relatives in Common” on my match page with RA, I see that RA and I do share DNA, meaning triangulate, with several relatives on my list. That’s what “Shared” means in this context at 23andMe – shared same segment.

Unfortunately, RA has not entered any additional information such as a tree link, family surnames, or locations.

I’ll message RA for more information as soon as I finish my next bite of chocolate.

GEDmatch is a bit different because your match list is not pre-generated, meaning there is no stored match list so no ability to create and save notes for matches.

At GEDmatch, I did a One-to-Many comparison which allowed me to view my match list.

In the far right column, you can see the testing company and test version. A=Ancestry, F=FTDNA, and M=23andMe along with the version when it says the results were migrated to the current platform. Otherwise, you’ll see the name of the testing company your match uploaded from more recently.

I selected an Ancestry match since I’ll match the people from MyHeritage and FamilyTreeDNA at their respective sites that already have triangulation capability. I will match close matches at 23andMe, but 23andMe caps matches at 1500 (unless you’re on the V5 chip WITH a subscription), so some matches may be here that aren’t there.

Ancestry testers are my best bet for finding new triangulated matches at GEDmatch because Ancestry doesn’t support triangulation on their own platform.

Based on my match’s name, I think the first person on this match list that I can’t identify is the same match, Christopher, that I was working with at Family Tree DNA. He uploaded 4 different files to GEDmatch, including an Ancestry file. This tells me he might have a nice tree at Ancestry since he’s obviously interested enough in genealogy to test multiple places😊

I went back to the main GEDmatch menu and selected Triangulation from the Tier 1 (paid subscription) options. Triangulation selects your closest matches and indeed, Christopher was among the triangulated groups with other people I recognize, providing immediate hints as to how we are related.

Next, I’m going to run over to Ancestry to see if indeed, I can find Christopher and view his tree there.

Unfortunately, I can’t find Christopher at Ancestry by the name he used elsewhere, although I do see a good candidate using initials but who has a private tree☹

Time for another chocolate!

Fortunately, I have Christopher’s email from GEDmatch and FamilyTreeDNA, so I can send him a friendly email introducing myself and asking about his genealogy.

DNA Tidbit #1 – Summary

Surprisingly, with reviewing just 5 triangulated matches at each vendor, I found a LOT to work with and discovered the ancestral lines through which several people are related to me, even if I can’t isolate exactly which ancestor. I painted each of those matches at DNAPainter. I’m currently sitting at 90% of my segments painted, which means they are identified with a specific ancestral line. Every identified match gets me closer to 100%.

I’m left with the distinct impression that after I find genealogical connections with these closest matches, that the leftover matches that triangulate will be the ones to break down brick walls.

Those will be the matches I really need to concentrate on, because somehow these people DO all match each other too, and the common ancestor they share between themselves may be the clue I desperately need. You know, the key to those people waiting just behind that brick wall of burned records and no last names.

Making that discovery will, indeed, be cause to celebrate with more than tidbits!!!

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Thank you so much.

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4 thoughts on “Introducing DNA Tidbits – DNA Tidbit #1: Triangulation”

  1. This sounds like a fun Idea. I always like to take time for exploring matches and ideas in novel ways (and a couple of trips down the rabbit hole). A fresh perspective is often surprisingly fruitful.

    I have gone through my accounts, selected a few matches and made a couple of notes on some interesting observations to look over this weekend. I am eager to pursue these.

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      • I must say, one of those rabbit holes paid off. It led to me sending a message to a woman who was not biologically related to me, but was someone who I thought might have knowledge about two people I was searching. She did, and was eager to connect as the part of the story I know about was a family secret, and as far as she knew there was no one alive who could answer her questions. I have now been able to confirm that my mother’s first cousins, who were in an orphanage, were not in the mass burial of children that I feared they were. The woman and I have exchanged some pictures of the relevant people.

        I have explored several matches with regards to triangulation and made not on some new leads. I wanted to mention one particular finding which provides an interesting clue. (I know 25-30 cM matches are not huge ones to work with, but some have been traceable or very informative and that is what I have to work with for the most part.) I have two matches on 23andMe. 23andMe indicates they match one another in the same location of chromosome 15 as they match me. I know from another site that one does not match my mother. Match one (M1) is 25 cM and has three other shared matches with me. Match two (M2) is the newer one I looked at for this exercise and is about 30 cM. M2 has around 60 other shared matches with me although none of them triangulate. One of the non-triangulated is one of my few larger matches and is a known 2C1R on my mother’s side. Two other matches on that list triangulate some maternal side matches. Some of the matches are also ones that I suspect are paternal. So, what does the discrepancy in the number of shared matches tell me? It tells me that although the segment shared with M2 is paternal, we may have other lines of connection through which we do not share DNA. At the very least, I know M2 seems to be historically more connected to my all Scottish-Irish direct line ancestry than M1. Indeed M1 shows about 12% European ancestry whereas M2 shows 100% European. But I could have guessed that based on the match lists.

        I have several other non-maternal matches on this segment on other sites and a shared match group of about 20 people on Ancestry. For the most part, they self-identify as Jamaican, of Jamaican descent, and/or live in Jamaica. Trelawny and Hanover have come up as ancestral locations for my matches, so that would be the northwest corner of Jamaica. One match states that he descends from theJamaican Maroons. I suspect that the sibling of one of my grandparents, or a descendant of a sibling, went to Jamaica.

        I have worked on and off with M1 and we work as much as possible towards bringing our trees together. We have established the match is through the maternal side for M1. M2 is a newer match and is one that I would now like to connect with to see if this is of any help in tracing back a little further on my paternal side. I know the line of possible connection was not wealthy and likely on the wrong side of the prevailing political sentiment of their times. Banishment lists contain many surnames associated with that side. It is my understanding that those who were banished were eventually allowed to become landowners, but it is an area of Scottish-Jamaican history that M1 and I are just beginning to explore.

        I have now gone through all the sites and identified a couple of additional matches on this chromosome with mainly Scottish-Irish ancestry. So I will also try connecting with them while trying to create trees. The further back I can go on this segment on the UK side of the ocean, the more I can narrow down where to look for people who left for Jamaica.

        There are several occasions, similar to this scenario, where I may not have found the MRCA, but have learned much by working on matches from widely spread geographic regions. Although I understand how DNA and DNA matching work, I am still fascinated and awed that spitting in a tube reveals interesting details of family history such as this.

        Reply ↓

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