RootsTech 2025 – The Year of Discover and the New Mitotree

Last week, RootsTech was a whirlwind and full of discoveries – which, ironically, was the 2025 theme.

I always take you along with me and share the RootsTech experience, start to finish, so here’s my 2025 “feet on the ground” report.

I might, just might, have overcommitted myself. I taught the half-day DNA Academy,  three more sessions, plus several other commitments such as book signings, get-togethers, and interviews.

One class, “DNA for Native American Genealogy,” was a live webinar from the floor of the expo hall. You can watch that here for free, if you’re interested.

Unfortunately, none of my other sessions were recorded, but I’ll see what other alternative options may be available to bring those to you.

Additionally, I did two book signings at the GenealogyBank booth, along with two other authors, Drew Smith and Sunny Morton. I’m sorry, I don’t have any pictures. I should have asked someone to take some.

There were long lines and books sold out. Still, you can order either of my books, The Complete Guide to FamilyTreeDNA – Y-DNA, Mitochondrial, Autosomal and X-DNA or DNA for Native American Genealogy, at Genealogical.com. Thank you to GenealogyBank for being so welcoming.

The book signing was particularly fun because people shared their success stories or their hopes of what they want to achieve. I met a couple of new cousins too! Even people waiting in line were helping each other with information about research resources.

I had created my “RootsTech plan” for sessions I wanted to attend, but I was only able to actually attend one of those. Several were happening at the same time as mine, or directly before or after. As a presenter, you arrive early to get set up and make sure everything is working correctly.

Then, after your session, attendees have questions and are interested in your topic, which is a good thing. So essentially, you can’t attend sessions either before or after your session either.

Before I share photos, I’d like to share something else.

It’s About the People

I have never attended RootsTech for the classes, although there are wonderful offerings – and I have enjoyed them immensely.

Having said that, for me, the best part of RootsTech is the people. People I know and love but never get to see – many of whom I met in-person at RootsTech initially. I get to meet my blog followers. I meet with or reconnect with friends and cousins from around the world. I am privileged to talk with people about their challenges and their victories – when they’ve broken through a brick wall using DNA that they could never have otherwise achieved. People collaborating and helping each other. It’s all beautiful.

The reason I started blogging in the first place, and the reason all 1750 articles are free, is because I wanted to help people do just that – confirm ancestors, find ancestors, and connect with their fsmily.

My cousins that I’ve met through genealogy are some of my closest friends and closest family members. Outliving everyone is a mixed blessing but it makes me extremely grateful for my various cousins since all of my siblings and close family, with the exception of the next generation, have transitioned to the land of the ancestors.

So, yea, for me, RootsTech is about connecting and reconnecting with the people.

That’s also why I never get anything done because I’m always talking with someone.

Additionally, this particular RootsTech was a celebration.

Mitotree Release

Just a few days before RootsTech, the Million Mito Team at FamilyTreeDNA released the brand new Mitotree, 5 years in the making, reconstructing the tree of humankind to reflect our combined heritage more accurately.

At RootsTech 2020, I was honored to announce the Million Mito Project, and the new Mitotree initiative was born.

At some point, I will write about the deep, personal significance of the Mitotree for me,  but for now, suffice it to say that there is something profoundly moving about rewriting the tree of humankind and in doing so, giving a voice to our ancestors from long ago. Yes, I know many of them are thousands or even tens of thousands of years old, but had they not survived, we would not be here today. Now we can identify who they are and that they lived.

Million Mito Team, left to right, Goran Runfeldt, Dr. Paul Maier, me, Dr. Miguel Vilar, Bennett Greenspan, John Detsikas

Our amazing Dream Team has given life to our ancestors and said their names once again, even if their name is a mitochondrial DNA haplogroup. Four team members, Goran, Paul, me and Bennett were at RootsTech. Where else can you actually approach and speak with the actual scientists?

When I say RootsTech is about the people, I know that I am related to every single individual at RootsTech, it’s just a matter of how far back in time. So are you.

Just think about the significance of that for a minute.

Every. Single. Person.

The other end of the mitochondrial DNA spectrum is genealogy, of course, and the new Mitotree with it’s haplotype clusters brings mitochondrial DNA results into the genealogical timeframe. In future articles, I’ll be writing about each one of the new tools, what they mean, and how to use them.

Dr. Paul Maier, lead scientist doing most of the hard science behind Mitotree, had the much-deserved honor of introducing the Mitotree to genealogists at RootsTech.

I’m not sure the audience understood they were witnessing history unfold, but they clearly were. We needed a drum roll and some balloons!

This wasn’t like most vendor announcements of a new product or feature – this was a major scientific achievement that led to genealogical benefits.

In celebration, I asked my friend to make double helix zipper pulls so that I could give them to colleagues, friends and cousins that I ran into at RootsTech. It’s my way of celebrating and sharing the joy!

Five years is a very long time to work on a project. The Mitotree is a massive accomplishment. Every customer at FamilyTreeDNA who has taken the full sequence test received their new haplogroup either the week before or during RootsTech, AND, the second updated version of the tree was released too.

While this is truly wonderful, the true highlight is the testimonials – seeing how Mitotree is actually helping people break through their brick walls.

Here’s just one.

Breathless Testimonial

I’m going to try to convey this exactly as it happened.

A lady that I don’t know literally runs up to me in the hallway. This isn’t unusual. She was so excited that what she said was one long breathless sentence, which I’m going to try to reconstruct here, although I’m adding a bit of punctuation. I also can’t remember how many “greats” were attached to the “grandmother,” but you’ll get the idea.

Roberta, Roberta, I’m so excited – I just wanted to let you know – I found my ancestor using mitochondrial DNA. I got my new haplogroup and I had like 47 matches before but now they are clustered together so I could focus…and there were three matches in my cluster…and one of them had an EKA but the other didn’t…so I built out the EKA matches’ tree and guess what??? They were from the same place and then I found that her great-great-grandmother’s sister is my great-great-grandmother but she had her surname so now I have more generations too. OMG I ‘m so excited I could never have broken through this wall without mtDNA because I had no surname. This is THE MOST CONSEQUENTIAL DNA TEST I’VE EVER TAKEN, and I’ve taken them all. Thank you, thank you!

And with that she quickly hugged me and ran off to something she was obviously late for.

I never got to say one word, which was fine, but I stood there with tears in my eyes, thinking to myself, “This – this is what it’s all about.”

It doesn’t get better than this!

I want to hear your stories too. I just scaled my fourth brick wall last night using the new Mitotree and mtDNA Discover features.

RootsTech Week

RootsTech week started early for me – as in leaving the house at 3 AM Sunday. I fly on Sunday because the flights are cheaper and because the pre-conference meetings and events begin on Monday.

We took off into the dawn, jetting our way westward through the azure blue sky.

I have never gotten over the majesty and beauty of the Rocky Mountains.

And then, of course, the Great Salt Lake, for which Salt Lake City is named.

Looking at the Salt Palace across the street from the Marriott hotel. The silver building is the new Hyatt which is attached to the conference center behind the windmills which extends another very long block to the right, out of view. The mountain range is visible in the distance, and the beautiful sunset.

Speaking of the Marriott hotel, several people have asked if it was any better this year, and if I got trapped in the fire exit again, like last year.

No, I didn’t get stuck because I didn’t tempt fate again. It looked just the same though, so I’m presuming nothing has changed. Furthermore, there was no heat in my room, so they gave me a space heater and a pass to the concierge level – which they did not do last year.

That was kind of them, but food ran out, and there was only one poor server in the restaurant. I’m not even going to mention the nauseating thing that happened with my food. Let’s just say I’m not picky, but I will NEVER eat there again, and that makes it particularly difficult because there’s very little close by, especially when you’re exhausted.

I’m hoping that RootsTech will negotiate someplace different for speakers in the future. I’ve stayed in a lot of Marriotts and most of them are just fine. I have never had issues like this with any of them, let alone repeat issues year after year.

The good news is that we’re not there for the hotel, and the fun began on Monday.

Monday

My interviews began on Monday morning with “Mondays with Myrt” at the FamilySearch Library, which you can view here beginning about 16 minutes.

Mondays with Myrt is a RootsTech tradition and Myrt incorporates people present in person and tuning in virtually as well. Left to right, Kirsty Gray from England, John Tracy Cunningham, me and Myrt. Kirsty had a huge breakthrough that she shared with us just a few minutes after it happened.

I met John at the ECGGS Conference last October. He’s one of the few people I know whose 8 great-grandparents were born in the same county. I’m so jealous. Mine were either born in or first generation immigrants from four countries.

Sometimes the broadcast waiting area is just as much fun as the actual broadcast – in part because it’s the first day of RootsTech week and everyone is so excited to see their friends that they haven’t seen in forever. Call is a reunion!

Do Kirsty Gray and I look like we’re about to get into mischief?

Behind me is the first group of folks to be interviewed.

Pat Richley-Erickson, aka Myrt, Cheryl Hudson Passey, Laura Wilkinson Hedgecock, and Jenny Horner Hawran.

This is the livestream room at the FamilySearch Library. The waiting area for the next group is to the right, and the three presently being interviewed are sitting on the left beside Myrt.

For those who know Gordon, aka Mr. Myrt, he’s coordinating interviewees outside the livestream room. His job is herding cats and he’s the nicest cat-herder you’ll ever meet!

Pre-RootsTech Library Research

I love the FamilySearch Library. It feels like coming home to me.

So many passionate genealogists at every level – learning and searching. Lots of volunteer helpers available, too.

Normally, I create a research plan for the library, but I had been so utterly slammed between preparing my several RootsTech sessions and the Mitotree release that I hadn’t really been able to prepare anything.

I did, however, have a group of ancestors in mind that settled in the Oley Valley in Pennsylvania, so I decided to focus on the Berks County books.

I won’t bore you with the details, but among other things, I found confirmation that the Hoch surname is also the same as High and Hoy, which explains some very confusing Y-DNA results. So even though I didn’t get much productive time there, I did find something very useful in the land records.

I also ran into cousins and friends, of course, which is why I didn’t get more actual research done.

I knew Judy Nimer Muhn, at left, was going to be at RootsTech as a speaker, and I knew we connected through Acadian lines, but we never took the time to really piece together that puzzle.

My cousins, Mark and Manny were also coming for RootsTech, and to visit the library, for the first time. Mark, Manny and I visited Nova Scotia together in the summer of 2024, chasing our ancestors.

You know, fate is a funny thing.

We all descend from Acadian, Francois Savoie who was born about 1621 in France, but settled in Acadia, today’s Nova Scotia. Mark, Manny and I knew that we are cousins through Francois, but Judy and I did not. Mark, Manny and I ran into a local historian, Charlie Thibodeau, the Acadian Peasant, last year, outside of Port Royal. It just so happened that he was taking another couple to see the remains of the Savoie homestead deep in the salt marshes at BelleIsle.

We asked if we could join them, and Charlie was kind enough to include us. It was a long, brutally hot, tick-infested hike through the swamp, but oh so worth it!

We also found the well, located between three homesteads.

The year before, Judy had been in the same place in Nova Scotia, found the same man, Charlie, at the BelleIsle Hall Acadian Cultural Centre, and he had taken her to the remains of the same homestead.

And here we all four are in Utah.

What are the chances?

Needless to say, we had a LOT to talk about, and still do. Unfortunately, I wasn’t able to get to Judy’s talk, but Mark and Manny attended.

I ran into Katy Rowe-Schurwanz, the FamilyTreeDNA Product Manager at the library too, and look what she’s wearing – a mitochondrial DNA scarf. How cool is that!

The rest of Tuesday and most of Wednesday morning were spent trying to update my several presentations to reflect newly released information by various vendors and practicing the timing of the presentations. I had another interview, and more people were arriving.

I found time to visit Eva’s Bakery about 3 blocks from the Salt Palace. If you’re ever in Salt Lake City, Eva’s is a must! Lunch is wonderful, and so are their French pastries.

Wednesday is “tech prep” day at RootsTech, along with speaker instructions and then the Speaker Dinner.

Steve Rockwood, President and CEO of FamilySearch always delivers an inspirational message and this year did not disappoint.

If you’ve wondered about RootsTech conference stats, they provided this information. I can’t even imagine trying to coordinate all of this – and that’s not including the vendors, expo hall, technology in the presentation rooms, food, security and so much more.

Last year, in 2024, the final attendance numbers were more than 16,000 people in person and 4 million virtual attendees. I noticed a few days ago that there were more than half a million people participating in Relatives at RootsTech, which is still live until April 12th.

On Wednesday evening, after the Speaker’s Dinner, vendors in the Expo Hall were putting the final touches on their booths and preparing for the thousands of excited genealogists who would descend Thursday morning.

Discover

This year’s RootsTech theme was “discover” and attendees were greeted with this display just inside the door.

Attendees listed their discoveries on Post-its and could either post them on the board or plastic boxes, or on the green tree.

I placed my discovery from the day before at the library on the Rootstech tree.

Some people place their wishes here, kind of like a technology wishing well.

I couldn’t help but think of the new Mitotree, now forever green and growing, so I posted a second discovery, “Mitotree.”

Thursday – Opening Day

For those who don’t know, the Salt Palace Convention Center is two lengthy blocks long, a block wide, and two or three stories high, depending on whether you are in the front or rear portion. In other words, it’s massive and you need a map!

The huge Expo Hall with vendors is located in the center on the first floor and vendors have aisle addresses. The show floor is always very busy, and this year was no exception. One of the things I love is that spontaneous conversations just spring up between people who often find commonalities – common ancestors, common locations, and more. People compliment each other and join others at tables. It’s like a big family gathering of sorts.

I always try to walk the entire Expo Hall, because I really enjoy seeing the vendors and their wares, but this year, I never actually had enough time to traverse all the aisles. I took several pictures as I was passing through and running into people, but not nearly enough. I know I missed a lot, but there just wasn’t enough time and I arrived at RootsTech already tired.

However, the energy of RootsTech is like no place else and just infects you.

It’s like you can’t drink from the genealogy firehose fast enough!

Let’s Take a Walk

Ok, come along on a walk with me.

Left to right, Lianne Kruger, a speaker, and Courtney, in the FamilyTreeDNA booth. I believe they said they are cousins.

Daniel Horowitz, genealogist extraordinaire, in the MyHeritage booth. More about MyHeritage’s announcements shortly.

Geoff Rasmussen in the Legacy Family Tree Webinars booth. For those who don’t know, there’s lots of good material at Legacy, and the freshly recorded webinars are always free for a week.

Several vendors offer booth talks, including MyHeritage. I love their photo tools and use their site in some capacity almost daily.

One of the RootsTech traditions is ribbons. Collect one, collect ‘em all. Liv’s ribbons almost reach the floor. I think she wins!

Selfies are also a RootsTech tradition. Me, here with Jonny Perl of DNAPainter fame. I owe Jonny an apology as he asked me if I had a minute, and I had to say no because I was on the way to one of my own classes. I never got back to his booth to view his new features. Sorry Jonny – don’t take it personally!

Jonny released a new Ancestral tree version titled Places, so take a look here at his blog. I need to go look at my ancestors Places.

You’ll find this new feature under Ancestral Trees, Places. These are my most recent 8 generations. Just think of all those brave souls who climbed on a ship and sailed for the unknown. Check this feature out and have fun.

In a booth talk, Dave Vance, Executive Vice-President and General Manager at FamilyTreeDNA is speaking about the three types of DNA, which are, of course, Y-DNA, mitochondrial and autosomal DNA – all useful for genealogy in different ways.

Dave is explaining how in-common-with matches, also known as shared matches, operate with the chromosome browser. You can use the chromosome browser, shared matches, the new Matrix Tool, and download your match segment information at FamilyTreeDNA, a combination of features not available at any other vendor.

WikiTree, a free a moderated one-world-tree is one of my favorite genealogy tools. One of their best features is that you find your ancestor, and in addition to lots of sources, their Y-DNA, mitochondrial DNA, and those who are related autosomally are listed. Here’s my grandfather, for example.

Several DNA connections are listed. The further back in my tree, the more DNA connections are found, becuase those ancestors have more descendants.

WikiTree volunteers were wandering around taking pictures of “WikiTreers” holding fun signs.

Paul Woodbury, a long time researcher with Legacy Tree Genealogists, who specializes in DNA. I don’t take private clients anymore, and regularly refer people to Legacy Tree.

Me with Janine Cloud taking our annual RootsTech selfie. Janine, the Group Projects Manager at FamilyTreeDNA and I co-administer one of those projects and accidentally discovered a few years ago that we are cousins too. How fun is this!!!

I wanted this shirt, but by the time I got back to the booth, it was too late. I’m going to order it online from Carlisle Creations, in case you want one too. This is so me.

Land records are critically important to genealogists. Rebecca Whitman’s class was about plotting land plats. What she’s holding is a surveyor’s chain. You’ve read about chain carriers? This is what they carried to measure land boundaries – literally metes and bounds. Some of my best discoveries have been thanks to land records.

The only session I actually got to attend was Gilad Japhet’s “What’s New and Exciting at MyHeritage.” For those who don’t know, Gilad is the founder and CEO of MyHeritage and it’s always great to hear about the new features straight from the top executive who is, himself, a seasoned genealogist. That’s why he started MyHeritage in the first place – 22 years ago in his living room.

Gilad had several wonderful announcements, but the one I’m most excited about is their new Cousin Finder. Cousin Finder finds and reveals cousins who are DNA candidates if they have not yet taken a DNA test.

I’ll be writing more about the MyHeritage announcements soon, but you can read their blog about Cousin Finder now, here, and their Roundup here about the rest of their announcements!

My Last Class – Reveal Your Maternal Ancestors & Their Stories

My last class at the end of the final day of RootsTech was “Reveal Your Maternal Ancestors & Their Stories – Solving Mitochondrial DNA Puzzles.”

Had I tried to coordinate this presentation with International Women’s Day, I could never have done it, but fate winked and here I was.

I’m often asked what it’s like from the presenters’ perspective. This is one of the smaller ballrooms. My earlier sessions were in larger rooms, maybe 3 times this size. I took this picture about 15 minutes before the session started as people were beginning to drift in.

The amazing RootsTech techs had me wired up to microphones and had verified that the audio and video equipment was working correctly, so now it was just waiting.

My cousin, John Payne, who co-administers the Speaks surname project with me, came by and took this great picture of the two of us. We’ve made huge inroads connecting the various Speake(s) lines in America, plus finally proving our home village in England, thanks to the Big Y-700 test, followed by church records. All is takes, sometimes, is that one critical match.

As I sat there, waiting to begin the mitochondrial DNA session, I couldn’t help but reflect upon all of the women who came before me and how fortunate I was to have been in the right place at the right time to be a member of the Million Mito team.

These are my direct matrilineal ancestors who give me, and my daughter, pictured at left, their mitochondrial DNA. I felt them with me as I sat there, waiting.

The woman at furthest right, Barbara Drechsel (1848-1930), immigrated to Indiana from Germany as a child with her parents in the 1850s. Before her came thousands of generations of women with no photos, of course, and no names before Barbara Freiberger, another eight generations earlier, born about 1621 in Germany.

Before that, which was before church and other records, prior to the 30 Years War, this lineage came from Scandinavia where some of my exact matches are still found today.

Before beginning, I said a positive affirmation and thanked my ancestors – so very honored to introduce them. I know they were proud of me, a member of the team that opened the door to the distant past. I wouldn’t be here if not for every one of their lives.

In this session, I would discuss, for the first time ever, the new Mitotree and my/our connection to all of humanity some 7000 generations ago, more or less.

The mutations we carry over those generations form an unbroken chain of breadcrumbs, connecting us to mitochondrial Eve who lived about 145,000 years ago. We revealed that breakthrough finding in the Haplogroup L7 paper, published in 2022.

I’m still in absolute awe that we have been able to both reach that far back in time AND, at the same time, make the newest haplogroups and haplotype clusters genealogically relevant. I will write more about that soon, but for now, I wrote about the Mitotree release here and you can find articles by Katy Rowe-Schurwanz here and here.

I’m very excited about my new mitochondrial DNA results for my ancestral lines that I track and have already made headway on several.

I’m not the only one.

Not only was I excited about my results, many other people have had breakthroughs too, including Mark Thompson, one of our genealogy AI experts who also spoke at RootsTech. I particularly love his AI generated image.

If you haven’t yet, check your mitochondrial DNA results.

It’s a Wrap

Another year done, another RootsTech under our belts. Hopefully everyone is over the “conference crud” by now and are busily applying their newfound knowledge.

You can view either live-cast sessions or RootsTech webinars, here.

I saw a meme posted sometime during the conference that coined the term “exhausterwhelmulated,” a combination of exhausted, overwhelmed and overstimulated at the same time.

I added exhilarated and elated to the mix and asked ChatGPT to draw me a picture of someone at a genealogy conference feeling those simultaneous emotions.

ChatGPT titled this request “Genealogy Conference Overload,” which made me laugh.

The first two attempts looked like the person had a headache, which I fully understood, so I asked ChatGPT to make the person look happy to be there.

This person, carrying a coffee like I often do, looks like they have just discovered the great irony that they have chased the wrong ancestor for some 20 years – with “laugh or I’ll cry” mania being their overwhelm “go to” in that minute.

This one made me laugh too!

Yes, indeed, I think every single one of us, especially at RootsTech, has experienced this exact adrenaline-fueled emotion.

We leave with a VERY long to-do list, exhausted but full of anticipation and buoyed by excitement. Filled with so much gratitude for our cousins and fellow genealogists, the speakers, vendors, DNA to solve thorny problems, new tools and records, FamilySearch who sponsors RootsTech itself and their amazing employees, plus the legions of the volunteers who make it all work.

Thank you! Thank you! Thank you!

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Six Ways to Figure Out How We’re Related

In my latest Webinar, Six Ways to Figure Out How We’re Related, I discuss the various tools from Ancestry, FamilyTreeDNA, MyHeritage, and 23andMe – plus clusters from Genetic Affairs and the amazing DNAPainter.

This webinar lives in the Legacy Family Tree Webinar library, but as part of the “webtember” lineup, you can view it for free through the end of September.

It’s always exciting to discover a new match at one of the DNA testing companies, which, of course, begs the question of how you’re related.

So, what are the six ways to figure out how you’re related, and how do you use them?

Come along for a step-by-step guide!

Shared Matches

We begin with how each vendor handles shared matches, what that feature is called, where to find the information, and how to interpret what they are telling you.

23andMe goes a step further and creates a genetic tree, of sorts, although that functionality has changed since their breach last October.

Bucketing and Sides

Two vendors go a step further and provide unique tools to divide your matches maternally and paternally.

FamilyTreeDNA buckets your matches maternally and paternally (or both) based on matches you link to their profile cards in your tree. FamilyTreeDNA then uses your linked matches to triangulate with other matches and assign your matches accordingly, providing a maternal and paternal match list. Bucketing, also known as Family Matching, is one of my favorite tools.

Note that linking matches at FamilyTreeDNA requires that you have transferred your tree to MyHeritage. I wrote about that and provided instructions here and here, and produced a complimentary webinar, too.

Ancestry also divides your matches by parent, but they use a different technique based on their Sideview technology and either ethnicity or shared matches.

Surnames and Locations

Surnames and locations, either separately or together, provide HUGE hints!

MyHeritage provides a nice summary for each of your matches that includes ancestral surnames, a map of locations in common, and “Smart Matches” which shows you people in common in both of your trees. There are several ways to use these tools.

FamilyTreeDNA also provides a list of surnames. You can view either the surnames in common with a match, or all of their ancestral surnames, with locations if provided. The tester enters these surnames, and we review how to complete that step.

Ancestry also provides shared surnames, with clickable links to the number of people in your matches tree with that surname, plus common locations.

X-DNA

X-DNA is probably the most underutilized DNA matching tool. While each of the vendors actually test the X chromosome, only one, FamilyTreeDNA, provides X-matching. You can obtain X-matching results by uploading your DNA file to FamilyTreeDNA. I’ve provided upload/download instructions for all companies, here.

X-DNA has a very unique inheritance pattern because males only inherit an X chromosome from their mother which limits the number of potential common ancestors for any two testers. In other words, X-DNA matching does half your work for you!

Clustering Technology – AutoClusters, the Matrix and DNAPainter

In the past few years, match clustering has become a very useful tool. Clustering shows which of your matches match you and each other.

Genetic Affairs offers several flavors of these clusters, and both MyHeritage and GEDmatch have incorporated Genetic Affairs clusters into their product offerings.

If you haven’t used AutoClusters yet, by all means, try them out.

FamilyTreeDNA offers the Matrix, a slightly different version of clustering. You can select 10 people from your match list to see if they also match each other. Shared matches don’t automatically mean triangulation between you and those two people, or even that all three people descend from the same line. However, if the people are bucketed to your same side (parent) and they share common segments with you in the chromosome browser, they triangulate.

You’ll want to paint those matches to DNAPainter to determine which ancestor you share, especially if they haven’t provided a tree.

DNAPainter provides your chromosomes as the “canvas” upon which to paint your matches in order to correlate segments with ancestors and identify common ancestral lines with mystery matches.

Three vendors, FamilyTreeDNA, MyHeritage, and GEDmatch provide segment information with matches for you to paint. I illustrate how I walk segments back in time, identifying our most distant common ancestor possible.

Theories of Family Relativity and ThruLines

Both MyHeritage and Ancestry provide a combination of DNA matching and tree triangulation, where they search the trees of your DNA matches to find common ancestors with you – although their implementation is different.

MyHeritage’s Theories of Family Relativity provides varying theories about common ancestors for you and a specific match using both trees and historical documents. You can review the various pathways and confirm or reject theories. I love this tool.

Ancestry’s Thrulines functions a bit differently, showing you all of your matches that descend from a common ancestor in all your matches’ trees. Sometimes, the trees are incorrect, but Theories of Family Relativity and ThruLines should still be used as hints.

I showed how ThruLines helped me discover what happened to one of my ancestor’s grandchildren who was lost to the family at his mother’s death – and to all of us since. Not anymore.

Bonus – Y-DNA and Mitochondrial DNA at FamilyTreeDNA

Only FamilyTreeDNA offers both Y-DNA and Mitochondrial DNA testing and matching. All of the tools above pertain to autosomal DNA testing, which is named Family Finder at FamilyTreeDNA. Illustrated by the green arrow below, autosomal DNA testing measures and compares the DNA you inherited from each ancestral line, but that’s not the only game in town.

Y-DNA, in blue, for males, tracks the direct paternal line, which is the surname line in Western cultures. Mitochondrial DNA, in red, is passed from mothers to all of their children. Therefore, everyone can test, revealing matches and information about their mother’s direct matrilineal lineage.

Y-DNA testing includes the amazing Discover tool with a baker’s dozen different reports, including ancient DNA. Mitochondrial DNA will soon have its own MitoDiscover after the rollout of the new Mitotree.

Both tests include “Matches Maps” to help you determine how you are related to your matches, as well as where your ancestors came from before the advent of surnames.

The Advanced Matching feature allows you to select multiple tests to see if your matches match you on combined types of tests.

Tune In

Now that you know what we cover in the webinar, please tune in to see how to use these awesome tools. Be sure to fish in all four “ponds” plus GEDmatch, where you may find people who didn’t test at a company that provides a chromosome browser or matching segment information.

Tools provided by the DNA testing vendors facilitate multiple ways to determine how we match and which ancestor(s) we have in common.

You can watch the webinar, here.

Additionally, subscribers to Legacy Family Tree Webinars have access to the 25-page syllabus with even more information!

A Legacy Family Tree Webinar subscription normally costs $49.95 per year, but through the end of September, there’s a coupon code good for 20% off. Just click here, then enter webtember24 at the checkout.

Enjoy!

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DNA Academy Webinar Series Released

Great news! Legacy Family Tree Webinars has just released DNA Academy.

DNA Academy is a three-part series designed to introduce the basics of DNA for genetic genealogy and how Y-DNA, X-DNA, mitochondrial and autosomal DNA can be utilized. Each of these different types of DNA serves a different function for genealogists – and reveals different matches and hints for genealogy.

  1. DNA Academy Part 1 introduces genetic genealogy basics, then, Ancestry’s DNA tools – including their new pricing structure for DNA features. Click here to view.
  2. DNA Academy Part 2 covers FamilyTreeDNA’s products. Click here to view the webinar, which includes:
    1. Y-DNA for males which tracks the direct paternal line
    2. Mitochondrial DNA for everyone which tracks your direct maternal line – your mother’s mother’s mother’s lineage
    3. Autosomal DNA which includes matches from all of your ancestral lines and along with X-DNA matching, which has a very distinctive inheritance path.
  3. DNA Academy Part 3 includes MyHeritage, 23andMe, and third-party tools such as DNAPainter and Genetic Affairs. Click here to view.

Legacy Family Tree Webinars has graciously made Part 2, the FamilyTreeDNA class, free through August 22nd for everyone – so be sure to watch now.

After August 22nd, Part 2 will join Part 1 and Part 3 in the webinar library for subscribers with more than 2240 webinars for $49.95 per year.

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I receive a small contribution when you click on some of the links to vendors in my articles. This does NOT increase your price but helps me keep the lights on and this informational blog free for everyone. Please click on the links in the articles or to the vendors below if you are purchasing products or DNA testing.

Thank you so much.

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Pedigree Collapse and DNA – Plus an Easy-Peasy Shortcut

Pedigree collapse can be responsible for you sharing more DNA than expected with another person.

What is pedigree collapse?

Pedigree collapse occurs when you descend from the same ancestor(s) through more than one path. In other words, you descend from those ancestors through two different children. Therefore, when matching with someone else who descends through those ancestors, you may share more DNA than would be expected from that level of relationship on the surface, meaning without pedigree collapse.

Endogamy is different and means that you descend from a community of ancestors who descend from the same group of ancestors. Often out-marriage is discouraged or otherwise impossible, so all of the group of people share common ancestors, which means they often match on segments without sharing close ancestors. Examples of descent from endogamous populations are Jewish, Amish, Brethren, Acadian, Native Hawaiian, Māori, and Native American people, among others.

I wrote about the difference between pedigree collapse and endogamy in the article, What’s the Difference Between Pedigree Collapse and Endogamy?

I’ve also written about endogamy in the following articles:

Degrees of Consanguinity

If you’re a genealogist, and especially if you’ve worked with Catholic church records, you’ve probably heard of “degrees of sanguinity,” which are prohibited blood relationships in marriage. For example, siblings are prohibited from marrying because they are too closely related, according to church doctrine.

By SVG remake by WClarke based on original by User:Sg647112c – Own work, CC BY-SA 4.0, https://commons.wikimedia.org/w/index.php?curid=54804980

Today, we think of the genetic results of inbreeding, but originally, relationships (and consanguinity) also had to do with inheritance.

Essentially, marriages are prohibited by degree of sanguinity, and that degree is calculated based on this relationship chart. Prohibited degrees of consanguinity changed over time. Sometimes, a priest granted dispensation for a couple to wed who was of a prohibited degree of sanguinity. That’s a genealogy goldmine because it tells you where to look for common ancestors. It also tells you something else – that you may share more DNA with other descendants of that couple than one would otherwise expect.

More Than You Ever Expected

Recently, I’ve been working with an academic research team on a very interesting ancient DNA case that involves pedigree collapse. Doing the genealogy and genetic work on how much DNA was expected in a match without pedigree collapse, and how much was expected with pedigree collapse, was very interesting.

The team was working to confirm relationships between people in a cemetery. The burials shared more DNA than anticipated for who the people were believed to be. Enter pedigree collapse.

I can’t disclose the circumstances just yet – but I will as soon as possible. It’s an extremely interesting story.

We needed to ensure that readers, both academic and more generally understood pedigree collapse and our calculations. Why did burials share higher than expected DNA than indicated by the expected relationships? This puzzle becomes much more interesting when you add in pedigree collapse.

Academic researchers and scientists have access to models and mathematical algorithms that normal air-breathing humans don’t have easy access to.
So, what do you do if you and a match have a known pedigree collapse in your tree? How much DNA can you expect to share, and how do you calculate that?

These are all great questions, so let’s take a look.

I’m sharing the PowerPoint slides I prepared for our team on this topic. I’ve removed anything that would identify or even hint at the project and modified the slides slightly for easier consumption.

This presentation has never been given publicly, so you’re first! It seemed a waste to do this work and not share it!

Pedigree Collapse and DNA

Pedigree collapse occurs when you share an ancestor or ancestors through different pathways. In this case, the person at the bottom is the child of parents who were third cousins, but the father’s grandparents were also first cousins.

First cousin marriages were common in the not-too-distant past. Today, you could easily marry your third or fourth cousin and not even realize it unless someone in your family just happened to be a genealogist.

Genealogists use various tools to calculate the expected amount of shared DNA in relationships – first cousins, siblings, or half-siblings, for example. Both the Shared cM Project at DNAPainter and SegcM at DNA-Sci Tools provide tools.

Take a look at the article, DNA: In Search of…Full and Half-Siblings, for some great examples.

First cousins share common grandparents. Their child inherits DNA from two paths that lead back to the same ancestors. Some of that DNA will be the same, meaning the child will or can inherit the same ancestral segment from both parents, and some will be different segments from those ancestors that the parents do not share with each other.

Inheritance – How It Works

Let’s look at inheritance to see how this happens.

Let’s start with full and half-siblings.

Each child inherits half of their DNA from each parent, but not entirely the same half (unless they are identical twins.)

Therefore, full siblings will match on about 50% of their DNA, which is illustrated by the segments on the chromosome browser. However, and this will be important in a minute, about 25% of their DNA is exactly the same, when compared to each other, on the chromosome inherited from their father and mother at the same location.

On the chromosome browser, you can see that three siblings do match. One sibling (the grey background chromosomes) is the person both other full siblings are being compared to, in the example above.

What you can’t determine is whether they share the exact same DNA on both their mother and father’s Chromosome 1, where the matches overlap, for example. We know they both match their sibling, but the top person could match the sibling due to a match from their paternal chromosome in that location, and the bottom person could match due to their maternal chromosome. There’s no way to know, at least not from that view.

The areas where the siblings share exactly the same DNA on both their maternal and paternal chromosome, both, with each other are called Fully Identical REgions (FIR), as compared to Half Identical Regions (HIR) where the siblings match on either their maternal or paternal copy of the chromosome, but not both.

23andMe used to provide a tool that displayed both types of matches.

Since the data exposure incident at 23andMe, they no longer provide this lovely tool, and since that help page is now gone as well, I doubt this view will ever be returned. Fortunately, I grabbed a screenshot previously.

The dark purple segments are fully identical, meaning that these two full siblings match on both their maternal and paternal chromosomes in that location. The magenta are half identical, which means they match on EITHER the maternal or paternal chromosome in that location but not on both chromosomes. Of course, no color (light grey) means there is no match at that location.

Please note that because 23andMe counts fully identical regions (FIR) twice, their total matching cMs are elevated. The other companies do NOT count those regions twice.
GEDmatch also shows both full and half-identical regions as described more fully, here.

In this full-sibling example from GEDmatch, the green segments are fully identical regions across both the maternal and paternal chromosomes.

The definition of FIR is that two people match on both their mother’s and father’s DNA on the same chromosome. Therefore, in following generations, there technically should not be FIR matches, but in some instances we do find FIR matches outside of full siblings.

Moving down another generation, first cousins may share SOME fully identical DNA, especially if they are from an endogamous population or their mothers are related, but less, and it’s generally scattered.

Here’s my Mom’s GEDmatch comparison to her first cousin. The purple-legend segment shows a match, and the green within that match shows fully identical locations.

You can easily see that these are very scattered, probably representing “chance” or population-based fully identical matching locations within a segment. Comparatively, the green FIR segments for full siblings are dense and compact, indicating a segment that is fully identical.

Evaluating matches for dense FIR segments (known as runs of homozygosity – ROH) is a good indicator of parental relatedness.

Double Cousins

Of course, if these people were double first cousins, where the wives of the siblings were sisters to each other – the first cousins would have large patches of dense green FIR segments.

First cousins share grandparents.

Double first cousins occur when two people share both sets of grandparents, meaning that brothers marry sisters. Normal first cousins share about 12.5% of their DNA, but double first cousins share about 25% of their DNA.

In this case, Sharon and Donna descend from two brothers, James and Henry, who were sons of Joseph and Jane. In this scenario, James and Henry married unrelated women, so Sharon and Donna are first cousins to each other.

Double first cousins share both sets of grandparents so they would inherit FIR from both sets of siblings.

You need to be aware of this, but for now, let’s stick with non-double relationships. You’re welcome!

DNA Inheritance

Here’s a different example of DNA inheritance between two siblings.

  1. You can see that in the first 50 cM segment, both siblings inherited the same DNA from both parents, so they match on both their mother’s and father’s chromosomes. They match on both the 50 cM green and 50 cM pink segments. 23andMe would count that as 100 cMs, but other vendors only count a segment IF it matches, NOT if it matches twice. So, other vendors count this as a 50 cM match.
  2. In column two, these two people don’t match at all because they inherited different DNA from each parent. In this example, Person 1 inherited their maternal grandmother’s segment, and Person 2 inherited their maternal grandfather’s segment.
  3. In column three, our siblings match on their paternal grandmother’s segment.
  4. In column four, no match again.

How much can we expect to inherit at different levels – on average?

Different tools differ slightly, and all tools provide ranges. In our example, I’ve labeled the generations and how much shared DNA we would expect – WITHOUT pedigree collapse.

Ancestral couple Inherited cM Inherited %
Gen 1 – Their children 3500 cM 50
Gen 2 – Grandchildren 1750 cM 25
Gen 3 – Great-Grandchildren 875 cM 12.5
Gen 4 – GG-Grandchildren 437.5 6.25
Gen 5 – GGG-Grandchildren 218.75 3.125
Gen 6 – GGGG-Grandchildren 109.375 1.5625
Gen 7 – GGGG-Grandchildren 54.6875 .078125

Please note that this is inherited DNA, not shared (matching) DNA with another person.

Adding in pedigree collapse, you can see that we have three Gen 1 people involved, three Gen 2 descendants, and two Gen 3 and Gen 4 people.

Each of those people inherit and pass on segments from our original couple at the top.
We have three distinct inheritance paths leading from our original couple to Gen 5.
We have a first cousin marriage at Gen 2, at left, which means that their child, Gen 3, will have an elevated amount of the DNA of their common ancestors.

In Gen 4, two people marry who both descend from a common couple, meaning their child, Gen 5, descends from that couple in three different ways.

Did your eyes just glaze over? Well, mine did, too, which is why I had to draw all of this out on paper before putting it into PowerPoint.

The Gen 5 child inherits DNA from the ancestral couple via three pathways.
The next thing to keep in mind is that just because you inherit the DNA from an ancestor does not mean you match another descendant. Inheritance is not matching.

You must inherit before you can match, but just because you and someone else have inherited a DNA segment from a common ancestor does not guarantee a match. Those segments could be in different locations.

Categories of DNA

When dealing with inheritance and descent, we discuss four categories of DNA.

  • In the first generation, full siblings will, in about 25% of their locations, share the same DNA that has been inherited from both parents on the same chromosome. In other words, they match each other both maternally and paternally at that location. Those are FIR.
  • The DNA you inherit from an ancestor.
  • The DNA that both you and your cousin(s) inherit from a common ancestor and match on the same location. This is shared DNA.
  • The DNA that both you and your cousin(s) inherit from a common ancestor, but it’s not in the same location, so you do not match each other on that segment. Just because you inherit DNA from that ancestor does not necessarily mean that your cousin has the same DNA from that ancestor. This is inherited but not shared.

Inheritance is Not The Same as Matching

Inheritance is not the same thing as matching.

Inheriting our ancestor’s DNA isn’t enough. We need to match someone else who inherited that same segment in order to attribute the segment to that specific ancestor.

Depending on how close or distant the relationship, two people may share a lot of DNA (like full siblings), or one segment in more distant matches, or sometimes none at all. As we reach further back in time, we inherit less and less of our increasingly distant ancestors’ DNA, which means we match increasingly fewer of their descendants. I wrote about determining ancestral percentages in the article,  Ancestral Percentages – How Much of Them is in You?

Based on how much DNA we share with other known relatives, we can estimate relationships.

Pedigree collapse, where one descends from common ancestors more than once, increases the expected amount of inherited DNA, which in turn increases the probability of a shared match with other descendants.

Ancestral Couple Matching Between Shared DNA ~cM Shared DNA ~% Range (Shared cM Project) FIR – Identical DNA
Generation 1 Full Siblings 2600 50 1613-3488 25%
Generation 2 First Cousins 866 12.5 396-1397 0
Generation 3 Second Cousins 229 3.125 41-592 0
Generation 4 Third Cousins 73 0.78125 0-234 0

Here’s an example through third cousins, including expected FIR, fully identical regions where full siblings match each other on both their maternal and paternal chromosomes in the same location.

I provided a larger summary chart incorporating the information from public sources, here, minus FIR.

Of course, double cousins, where two pairs of siblings marry each other, represent another separate level of complexity. DNA-Sci’s Double Cousin Orogen explains this here and also provides a tool.

Double cousins, meaning when two pairs of siblings marry each other, are different from doubly related.

Doubly related means that two people descend from common ancestors through multiple paths, meaning multiple lines of descent. Doubly related is pedigree collapse. Double cousins is pedigree collapse on steroids.

Pedigree Collapse, aka Doubly Related

Calculating expected inherited DNA from multiple lines of descent is a bit more challenging.

A handy-dandy chart isn’t going to help with multiple relationships because the amount of expected shared DNA is based on the number of and distance of relationships.

Please note that this discussion excludes X-DNA matching which has its own inheritance path.

It’s time for math – but I promise I’ll make this relatively easy – pardon the pun.

What’s Behind the Math?

So, here’s the deal. I want you to understand why and how this works. You may not need this information today, but eventually, you probably will. This is one of those “refer back to it” articles for your personal library. Read this once as a conceptual overview, then read it again if you need to work through the relationships.

This is easy if you take it one step at a time.

First, we calculate each path separately.

In the first generation, full siblings inherit identical (FIR) DNA on both their mother’s and father’s chromosomes.

In the second generation, the male inherits the maternal segment, and the female inherits the paternal segment.

In the third generation, their child inherits those segments intact from both of their parents. The child inherits from the ancestral couple twice – once through each parent.

In generation 1, those two segments were FIR, fully identical regions. Both of those men married unrelated wives. When their children, Gen 2, were born, they had either the maternal or paternal segment from their father because they had an entirely different segment in that location from their mother.

However, the child in Gen 3 inherited the original green segment from their father and the original pink segment from their mother – reuniting those FIR segments in later generations.

First Cousin’s Child

Let’s calculate the inheritance for the child of those two first cousins who married.

Ancestral couple Inherited cM Inherited %
Gen 3 – Great-Grandchildren 875 cM 12.5
Gen 3 – Great-Grandchildren 875 cM 12.5
Total 1750 cM 25

Normally, a Gen 3 person inherits roughly 875 cM, or 12.5% of their great-grandparent’s DNA. However, since their grandparents were first cousins, they inherit about twice that amount, or 1750 cM.

While a Gen 3 person inherits as much as a grandchild (25%) normally would from the original couple, they won’t match on all of that DNA. When matching, we need to subtract some of that DNA out of the equation for two reasons:

  • In the first generation, between siblings, some of their DNA was fully identical and cannot be identified as such.
  • In the second generation, they will each have some parts of the ancestral couple’s DNA that will not match the other person. So, they inherit the same amounts from their common ancestors, but they can only be expected to match on about 25% of that amount two generations later.

However, the child of first cousins who marry inherits more DNA of the common ancestors than they would if their parents weren’t related. It’s just that some of that DNA is the same, potentially on the maternal and paternal chromosomes again, and some won’t match at all.

While matching DNA is the whole point of autosomal DNA testing, fully identical DNA matching regions (FIR) cannot be identified that way. For the most part, other than identifying full and half-siblings, sometimes pedigree collapse, and parent-relatedness, fully identical DNA isn’t terribly useful for genealogy. However, we still need to understand how this works.

It’s OK if you just want to say, “I know we’ll share more DNA due to pedigree collapse,” but if you want to know how much more to expect, keep reading. I’d really like for you to understand use cases and be able to track those segments.

Remember, we will learn a super-easy shortcut at the end, so for now, just read. It’s important to understand why the shortcut works.

Sibling Inheritance Versus Matching

In order to compare apples to apples, sometimes we need to remove some portion of DNA in our calculations.

Remember story problems where you had to “show your work”?

Calculating Expected DNA

Here’s the step-by-step logic.

Ancestral couple Inherited Non-Identical cM Inherited %
Gen 1 first son 3500 50
Gen 1 second son 3500 50
Less identical segments (FIR) -1750 (subtracted from one child for illustration) 25
Gen 2 son 1750 25
Gen 2 daughter married Gen 2 son 875 12.5
Gen 3 – Their child path through Gen 2 son 875 cM 12.5
Gen 3 – Their child path through Gen 2 mother 437.5 cM 6.25
Their child total without removing identical segments 1750 cM 25
Their child total after removing identical segments 1312.5 18.75

Category cMs Most Probable Degree Relationship
No Pedigree Collapse 875 98% Great grandparent or great-grandchild, great or half aunt/uncle, great or half niece/nephew, 1C 3
Pedigree Collapse without identical segment removal 1750 100% Grandparent, grandchild, aunt/uncle, half-sibling, niece/nephew 2
Pedigree Collapse after identical segment removal 1312.5 56% grandparent, grandchild, aunt/uncle, niece/nephew, half-sibling 2

Just because you HAVE this much shared (and/or identical) DNA doesn’t mean you’ll match on that DNA.

Next, let’s look at Gen 5 child who inherited three ways from the ancestors.

If you think, “This will never happen,” remember that it did, which is why I was working through this story problem. It’s not uncommon for families to live in the same area for generations. You married who you saw – generally, your family and neighbors, who were likely also family.

Let’s take a look at that 5th generation child.

The more distantly related, the less pedigree collapse affects matching DNA. That’s not to say we can ignore it.

Here’s our work product. See, this isn’t difficult when you take it step by step, one at a time.

Ancestral couple Inherited Non-Identical cM Inherited %
Gen 3 Child total after removing identical segments 1312.5 18.75
Gen 4 father – half of Gen 3 father 656.25 9.375
Gen 5 child – half of Gen 4 father 328.125 4.6875
Gen 5 child – mother’s side calculated from ancestral couple normally 218.75 3.125
Total for Gen 5 Child 546.875 7.8125

Inheritance Ranges

Lots of factors can affect how much DNA a person in any given generation inherits from an ancestor. The same is true with multiple paths from that same ancestor. How do we calculate multiple path inheritance ranges?

As with any relationship, we find a range, or combined set of ranges for Gen 5 Child based on the multiple pathways back to the common ancestors.

Gen 5 Child Inherited Non-Identical cM Inherited %
Without removing either paternal or maternal identical cMs 656.25 9.375
After removing paternal identical cMs only 546.875 7.8125

 

After removing maternal cMs only 546.875 7.8125

 

After removing both paternal and maternal identical cMs 362.50 6.25
Normal Gen 5 no pedigree collapse 218 3.125

What About Matching?

Inheritance and matching are different. Most of the time, two people are unlikely to share all of the DNA they inherited from a particular ancestor. Of course, inheriting through multiple paths increases the likelihood that at least some DNA from that ancestor is preserved and that it’s shared with other descendants.

Two people aren’t expected to match on all of the segments of DNA that they inherit from a particular ancestor. The closer in time the relationship, the more segments they will inherit from that ancestor, which increases the chances of matching on at least one or some segments.

Clearly, pedigree collapse affects matching. It’s most pronounced in closer relationships, but it may also be the only thing that has preserved that ONE matching segment in a more distant relationship.

So, how does pedigree collapse actually affect the likelihood of matching? What can we actually expect to see? Is there a name for this and a mathematical model to assist with calculations?

I’m so glad you asked! It’s called Coefficient of Relationship.

Coefficent of Relationship

My colleague, Diahan Southard, a scientist who writes at YourDNAGuide has authored two wonderful articles about calculating the statistical effects of pedigree collapse.

You can also read another article about the methodology of calculating coefficient of relationship, here, on WaybackMachine.

Diahan is a math whiz. I’m not, so I needed to devise something “quick and dirty” for my own personal use. I promised you a “cheat sheet,” so here’s the methodology.

Two Inheritance Paths – First and Third Cousins

Let’s look at an example where two people are both first cousins and third cousins because their grandparents were also first cousins.

Let’s calculate how these two people are related. They are first cousins and also third cousins.

When calculating the effects of pedigree collapse, we calculate the first relationship normally, then calculate the second relationship and add a portion of the result.

Here’s the math.

Using the Shared cM Project for the expected amount of shared DNA for both relationships, we’ve calculated the expected range for this pedigree collapse relationship.

Tying this back to degrees of relatedness.

Let’s look at ways to do Quick Calculations using the publicly available Shared cM charts and my composite tables, here.

Using Average Shared DNA

This first methodology uses average expected amount of shared, meaning matching, DNA. Please note, I’m not necessarily expecting you to DO this now, just read to follow.

Using Average Inherited DNA

Here’s a second method using average inherited DNA, meaning people wouldn’t be expected to match on all of the inherited DNA – just a portion.

You can’t always use the shared cM charts because all relationships aren’t represented, so you may need to use the amount of expected inherited DNA instead of shared DNA amounts.

Methodology Differences

Remember, none of these methodologies are foolproof because DNA inheritance is random. You may also have additional relationships that you’re aware of.

So, what’s the easiest method? Neither, actually. I’ve found an even easier method based on these proven methodologies.

Easy-Peasy Pedigree Collapse Shortcut Range Calculation in 4 Steps

Now that you understand the science and reasoning behind all of this, you can choose from multiple calculation methodologies after drawing a picture of the relevant tree.

You’re probably wondering, “What’s the easiest way to do this?”

  • These quick calculation methods are the easiest to work with for non-scientists and non-math whizzes. These are the calculations I use because, taking into account random recombination, you can’t do any better than get close.
  • Also, remember, if you’re dealing with double relationships, meaning double first cousins, you’ll need to take that into consideration, too.
  • If endogamy is involved, your matches will be higher yet, and you should use the highest calculations below because you need to be on the highest end of the range – and that may still not be high enough.

In these Easy-Peasy calculations, you calculate for the lowest, then the highest, and that’s your range. Please note that these are options, and truly, one size does not fit all.

  1. For the lowest end of the range, simply use the average of the highest relationship. In this case, that would be 1C, which is 866 cM. Remember that you may not share DNA with third cousins. 10% of third cousins don’t share any DNA, and 50% of fourth cousins don’t.
  2. For the highest end of the range, find the second relationship in the Shared cM chart, divide the average by half, and add to the value from the closest relationship. In this case, half of the 3C value of 76 is 38.
  3. Add 38 to 866 for the highest end of the range of 904.
  4. If there’s yet another path to ANY shared ancestor, add half that amount too to calculate the high end of the range – unless it’s 4C or more distant, then don’t add anything.

You can see that this easy-peasy range calculation for pedigree collapse compares very well to the more complex but still easy calculations.

  • Easy-peasy calculation: 866-904
  • Other calculation methods: 850-903
  • For this same relationship combination, Diahan’s statistical calculation was 850 cM.

Back to Genealogy

What’s the short story about how pedigree collapse affects genealogy?

Essentially, in close generations, meaning within a few generations of two first cousins marrying, descendants can expect to inherit and share significantly more DNA of the common ancestors, but not double the amount. As we move further away from those marriages in time, the effect becomes less pronounced and more difficult to detect. You can see that effect when calculating multiple paths where at the fourth cousin level, or more distant, those cousins have a 50% or greater possibility of not sharing DNA segments.

Of course, with multiple paths to the same ancestor, your chances of inheriting at least some segments from the common ancestor are increased because their DNA descends through multiple paths.

Today, close marriages are much less common and have been for several generations in many cultures, so we see fewer instances where pedigree collapse makes a significant difference.

Within a population or group of people, if pedigree collapse becomes common, meaning that there are multiple paths leading back to common ancestors, like our three-path example, DNA segments from the common ancestors are found among many people. Significant pedigree collapse becomes endogamy, especially if marriage outside of the group is difficult, impossible, or discouraged.

Normally, pedigree collapse is not recorded in actual records. It’s left to genealogists to discover those connections.

The exception, of course, is those wonderful Catholic parish records where the priest granted dispensations. Sometimes, that’s our only hint to earlier genealogy. In the case of the marriage of Marie-Josesphe LePrince to Jacques Forest, the priest wrote “dispense 3-3 consanguinity,” which tells us that they shared great-grandparents. It also tells us that their grandparents were siblings, that the bride and groom were second cousins, and that their children and descendants inherited an extra dose of DNA from their common great-grandparents.

How does that affect me today? Given that I’m their seventh-generation descendant – probably not at all. Of course, they are Acadian, and the Acadians are highly endogamous, which means I match many Acadians because all Acadians share the DNA of just a few founders, making it almost impossible to track segments to any particular ancestor. If it weren’t for endogamy, I would probably match few, if any, of their descendants.

Now, when you see those Catholic church dispensations or otherwise discover pedigree collapse, you can be really excited, because you understand the effects of pedigree collapse and how to calculate resulting matches! You might, just might, have retained a DNA segment from those ancestors because you inherited segments through multiple paths – increasing the probability that one survived.

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Ancestry’s ThruLines Are a Hot Mess Right Now – But Here Are Some Great Alternatives

Right now, ThruLines at Ancestry is one hot mess.

Aside from the inherent frustration, especially over a holiday weekend when many people had planned to work on their genealogy, I’d like to say, “don’t panic.”

I don’t have any inside information about what’s going on at Ancestry, and I’ve attempted to make contact through their support page with no luck. They make talking to a person exceedingly difficult; plus, it’s a holiday weekend, and they are probably inundated.

Regardless, I have an idea of what is happening. Ancestry has been in the midst of recalculating “things,” perhaps in relation to their other changes, which I’ll write about separately in a few days.

In any event, Ancestry SURELY MUST KNOW there’s a significant problem because I imagine thousands of their customers are screaming right about now. Adding another voice won’t be helpful.

Symptoms

  • You may not have ThruLines at all.
  • If you do have ThruLines, don’t trust the information, or more to the point, don’t trust that it’s in any way complete.

I have two tests at Ancestry, both connected to different trees so that my matches and Thrulines are calculated separately for each test.

Test One

My first Ancestry test is connected to my primary tree. I’ve been amassing Thrulines cousins ever since the feature was released. I have hundreds of cousin matches descended from some of my more prolific ancestors.

Additionally, my sister’s grandchildren have tested, as have other close relatives who have connected their tests to their trees.

Today, those people are still showing on my match list, but are NOT showing as matches in ThruLines. None of them. Most of my ThruLines ancestors are showing zero matches, and the rest are only showing very few. Ancestors who had hundreds before now have 2, for example.

Here’s an example with my cousin, Erik.

My grandfather, William George Estes, shown in Erik’s tree, above, is his great-grandfather. Erik is my half first cousin, once removed, and we share 417 cM over 16 segments.

Yet, looking at my ThruLine for William George Estes, neither he nor my other cousins are shown as matches. Same for William George’s parents, and so forth.

ThruLines is VERY ill right now.

Test Two

My second DNA test at Ancestry is even worse. There are no ThruLines calculated, even though my DNA is tree-attached, and I had ThruLines previously.

I see this message now, and I can’t even begin to tell you how irritating this is – in part because it suggests the problem is my fault. It’s clearly not. My tree hasn’t changed one bit. I’m not alone, either. I’ve seen other people posting this same message.

And yes, if you’re thinking that there is absolutely no excuse for this – you’re right.

However, outrage isn’t good for us and won’t help – so let’s all do something else fun and productive instead.

Productive Genealogy Plans

Here are some productive suggestions.

At MyHeritage:

At FamilyTreeDNA:

  • Build your haplogroup pedigree chart by locating people through different companies descended from each ancestor in your tree through the appropriate line of descent, and see if they have or will take a Y-DNA or mtDNA test.
  • Tests are on sale right now, and there’s no subscription required at FamilyTreeDNA for anything.
  • Check Y-DNA and mtDNA tests to see if there are new matches and if you share a common ancestor.

At 23andMe:

  • Check for new matches and triangulation.
  • Check to see if 23andMe has added any of your new matches to your genetic tree.

Remember, the parental sides are typically accurate, but the exact placement may not be, and 23andMe deals poorly with half-relationships. It’s certainly still worth checking though, because 23andMe does a lot of heavy lifting for you.

DNAPainter

For me, the most productive thing to do this weekend would be to copy the segment information from new matches with whom I can identify common ancestors at FamilyTreeDNA, MyHeritage and 23andMe – the vendors who provide segment data – and paint those segments to DNAPainter.

Not only does DNAPainter allow me to consolidate my match data in one place, DNAPainter provides the ability for me to confirm ancestors through triangulation, and to assign unknown matches to ancestors as well.

As you can see, I’ve successfully assigned about 90% of my segments to an ancestor, meaning I’ve confirmed descent from that ancestor based on my autosomal matches’ descent from that same ancestor – preferably through another child. Will new matches propel me to 91%? I hope so.

What percentage can you or have you been able to assign?

If you need help getting started, or ideas, I’ve written about DNAPainter several times and provided a compiled resource library of those articles, here.

Have fun!!!

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Paint LivingDNA Chromosome Segments to DNAPainter

LivingDNA entered the genetic genealogy landscape as a vendor in September of 2016, A British company, they were and remain focused on British Isles testers and ethnicity based on the POBI, People of the British Isles Study.

Initially, they provided only ethnicity results and high-level haplogroups, but added family matching relatively recently.

If you have not tested or uploaded to LivingDNA, you may want to read about the company and leadership, here, before doing so.

Family Matching

Please note that their family matching is imperfect, so exercise a great deal of caution.

This states that my mother’s kit, which I uploaded and own, has no matches.

My mother reportedly has no matches, including NOT TO ME. If I were to make a family inference from this, I would conclude that my mother is not my mother. That is very clearly not the case. For obvious reasons, it could be even more damaging within a family unit for a DNA company to report no matches between a father and child.

However, a second upload file from the same testing company for my mother at LivingDNA DOES reflect me as a match.

I have about 650 matches at LivingDNA, but I only share 141 matches with my mother. The rest would either be to my father’s side of the family, or identical by chance (IBC.)

Chromosome Browser

LivingDNA has been promising a chromosome browser “soon” for several years now, since at least the fall of 2017 when I spoke to them at Genetic Genealogy Ireland in Dublin. That long-awaited day has arrived. You can view your matches in a chromosome browser and paint your segments with your matches at DNAPainter to obtain additional information.

To briefly review, the purpose of a chromosome browser is to identify specific segments of your DNA that you share in common with your matches. These common segments will be associated with your common ancestors, presuming the match is identical by descent (IBD) and not identical by chance (IBC.) If you’re unfamiliar, you can read about those concepts in the article Concepts – Identical by…Descent, State, Population and Chance.

Assigning Common Segments

Of course, assigning common DNA segments with your matches to specific ancestors implies one of three things.

Either:

  1. A tree where you can identify a common ancestor or ancestral line with your match
  2. Shared matches with a family member you know
  3. Communications with your match to identify a shared ancestor

LivingDNA does not provide a tree function, so you cannot view other testers’ family trees. Neither do they provide a field for a link to an existing tree someplace else, so users are handicapped.

LivingDNA does provide a message facility, so you can message your matches and ask about their genealogy and where they may have a tree you can view.

Unless you recognize a match or your match provides you with a tree to view, you may only be able to identify common ancestors through previously identified shared matches.

Shared Matches

Your best bet is identifying a cousin or other family member at LivingDNA. I only have one match that I can identify, and that’s my mother.

I can click on our 141 shared matches in common to view that list.

Unfortunately, my closest shared match with my mother is 36 cM. Matches are not listed in segment size order. LivingDNA is not popular outside of the British Isles, but you never know where a useful match will pop up.

My closest match, other than my mother, is Christopher with whom I share 101 cM across five segments.

Christopher does not share a match with my mother, and 101 cM is too large to be IBC, so my conclusion would be that Christopher and I share ancestors on my father’s side.

I viewed the 17 shared matches Christopher and I have in common, but I don’t recognize anyone from the other testing sites.

I could, of course, message Christopher and ask about his genealogy.

However, there’s another option too. Because I’ve been painting my known matches at DNAPainter, I can now paint my match with Christopher, which might identify our common ancestor or at least provide a significant hint.

Chromosome Browser

My personal goal is to identify my DNA segments that descend from each ancestor, and to associate 100% of my DNA with an ancestor. Without knowing who our common ancestor is, painting matching segments is not terribly useful.

However, let’s say that I know who Christopher is, or that I recognize some of our 17 shared matches allowing me to identify our common ancestor(s).

By clicking on the right arrow, you’ll be able to view a selection menu.

By clicking on the blue Shared DNA Beta link, I can view my match with Christopher either on a chromosome browser, or in a table.

My common segments with Christopher are painted on my chromosomes, above.

Click on “table view” at the top to view only the segment data where Christopher matches me on chromosomes 1-22.

Painting at DNAPainter

Click on the “Copy segment data” tab in the upper right-hand corner to copy the segment data to paint at DNAPainter.

I have written several articles about using DNAPainter, which you can reference, here.

Open DNAPainter.

I selected “Paint a New Match” at DNAPainter, then pasted the copied segment information from LivingDNA.

Click on “Save Match Now’ in the lower right-hand corner.

You will need to select either the maternal or paternal side, or unknown.

We know that Christopher matches me on my father’s side because the match is large and we do not share my mother as a match.

Since I haven’t yet identified our common ancestor, I selected teal blue to differentiate the LivingDNA match.

As it turns out, Christopher at LivingDNA matches the same segments as another man named Christopher who tested at 23andMe. It’s the same person.

I identified my common ancestor with Christopher at 23andMe as Lazarus Estes and Elizabeth Vannoy, my great-grandparents.

At DNAPainter, I’ve assigned segments of other descendants of this couple the color grey. You can easily see that the same segment on chromosome 14 is assigned to several other descendants of Lazarus Estes and Elizabeth Vannoy.

Therefore, the additional 17 shared matches at LivingDNA with Christopher, assuming they are valid IBD matches, would descend from the same genetic line, if not the same couple. In other words, some of that DNA might have descended to me from Lazarus or Elizabeth, but might have descended to Christopher or others through the parents of either Lazarus or Elizabeth, or another common upstream ancestor.

Every segment has its own unique ancestral history.

Thanks to DNAPainter

LivingDNA has joined the group of vendors who provide a complimentary chromosome browser and segment information for their customers. Other DNA testing vendors who do as well include 23andMe, FamilyTreeDNA and MyHeritage, plus third-party GEDmatch.

A big thank you to DNAPainter for a comprehensive tool to track segments and assign them to ancestors in one easy-to-use all-inclusive tool.

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What Is a Sibling Anyway? Full, Half, Three-Quarters, Step, Adopted, Donor-Conceived & Twins

I’ve seen the term sibling used many different ways, sometimes incorrectly.

When referring to their own siblings, people usually use the term brother or sister, regardless of whether they are talking about a full, half or step-sibling. It’s a term of heart or description. It’s often genealogists who are focused on which type of sibling. As far as I’m concerned, my brother is my brother, regardless of which type of brother. But in terms of genetics, and genealogy, there’s a huge difference. How we feel about our sibling(s) and how we are biologically related are two different things.

Let’s cover the various types of siblingship and how to determine which type is which.

  • Full Siblings – Share both parents
  • Half-Siblings – Share only one parent
  • Three-Quarter Siblings – It’s complicated
  • Adopted Siblings
  • Donor-Conceived
  • Step-Siblings – Share no biological parent
  • Twins – Fraternal and Identical

Full Siblings

Full siblings share both parents and share approximately 50% of their DNA with each other.

You can tell if you are full siblings with a match in various ways.

  1. You share the same fairly close matches on both parents’ sides. For example, aunts or uncles or their descendants.

Why do I say close matches? You could share one parent and another more distant relative on the other parent’s side. Matching with close relatives like aunts, uncles or first cousins at the appropriate level is an excellent indicator unless your parents or grandparents are available for testing. If you are comparing to grandparents, be sure to confirm matches to BOTH grandparents on each side.

  1. Full siblings will share in the ballpark of 2600 cM, according to DNAPainter’s Shared cM Tool.

Keep in mind that you can share more or less DNA, hence the range. It’s also worth noting that some people who reported themselves as full siblings in the Shared cM project were probably half siblings and didn’t realize it.

  1. Full siblings will share a significant amount of fully identical regions (FIR) of DNA with each other, meaning they share DNA at the same DNA address from both parents, as illustrated above. Shared DNA with each other inherited from Mom and Dad are blocked in green. The fully identical regions, shared with both parents, are bracketed in purple. You can’t make this determination at FamilyTreeDNA, MyHeritage or Ancestry, but you can at both 23andMe and GEDmatch.

At GEDmatch, the large fully green areas in the chromosome browser “graphics and positions” display indicates full siblings, where DNA is shared from both parents at that location.

I wrote about the details of how to view fully identical regions (FIR) versus half identical regions (HIR) in the article, DNA: In Search of…Full and Half-Siblings.

  1. If your parents/grandparents have tested, you and your full sibling will both match both parents/grandparents. Yes, I know this sounds intuitive, but sometimes it’s easy to miss the obvious.

At FamilyTreeDNA, you can use the matrix tool to see who matches each other in a group of people that you can select. In this case, both siblings are compared to the father, but if the father isn’t available, a close paternal relative could substitute. Remember that all people who are 2nd cousins or closer will match.

  1. At Ancestry, full siblings will be identified as either “brother” or “sister,” while half-siblings do not indicate siblingship. Half-siblings are called “close family” and a range of possible relationships is given. Yes, Ancestry, is looking under the hood at FIR/HIR regions. I have never seen a full sibling misidentified as anything else at Ancestry. Unfortunately, Ancestry does not give customers access to their matching chromosome segment location data.
  2. Y-DNA of males who are full siblings will match but may have some slight differences. Y-DNA alone cannot prove a specific relationship, with very rare exceptions, but can easily disprove a relationship if two males do not match. Y-DNA should be used in conjunction with autosomal DNA for specific relationship prediction when Y-DNA matches.
  3. Y-DNA testing is available only through FamilyTreeDNA, but high-level haplogroup-only estimates are available through 23andMe. Widely divergent haplogroups, such as E versus R, can be considered a confirmed non-match. Different haplogroups within the same base haplogroup, such as R, but obtained from different vendors or different testing levels may still be a match if they test at the Big Y-700 level at FamilyTreeDNA.
  4. Mitochondrial DNA, inherited matrilineally from the mother, will match for full siblings (barring unusual mutations such as heteroplasmies) but cannot be used in relationship verification other than to confirm nonmatches. For both Y-DNA and mitochondrial DNA, it’s possible to have a lineage match that is not the result of a direct parental relationship.
  5. Mitochondrial DNA testing is available only through FamilyTreeDNA, but haplogroup-only estimates are included at 23andMe. Different base haplogroups such as H and J can be considered a non-match.
  6. A difference in ethnicity is NOT a reliable indicator of half versus full siblings.

Half-Siblings

Half-siblings share only one parent, but not both, and usually share about 25% of their DNA with each other.

You will share as much DNA with a half-sibling as you do some other close matches, so it’s not always possible for DNA testing companies to determine the exact relationship.

Referencing the MyHeritage cM Explainer tool, you can see that people who share 1700 cM of DNA could be related in several ways. I wrote about using the cM Explainer tool here.

Hints that you are only half-siblings include:

  1. At testing vendors, including Ancestry, a half-sibling will not be identified as a sibling but as another type of close match.
  2. If your parents or grandparents have tested, you will only match one parent or one set of grandparents or their descendants.
  3. You will not have shared matches on one parent’s side. If you know that specific, close relatives have tested on one parent’s side, and you don’t match them, but your other family members do, that’s a very big hint. Please note that you need more than one reference point, because it’s always possible that the other person has an unknown parentage situation.
  4. At 23andMe, you will not show fully identical regions (FIR).
  5. At GEDmatch, you will show only very minimal FIR.

Scattered, very small green FIR locations are normal based on random recombination. Long runs of green indicate that significant amounts of DNA was inherited from both parents. The example above is from half-siblings.

  1. At FamilyTreeDNA and 23andMe, most men who share a mother will also share an X chromosome match since men only inherit their X chromosome from their mother. However, it is possible for the mother to give one son her entire X chromosome from her father, and give the other son her entire X chromosome from her mother. Therefore, two men who do share a mother but don’t have an X chromosome match could still be siblings. The X is not an entirely reliable relationship predictor. However, if two men share an entire X chromosome match, it’s very likely that they are siblings on their mother’s side, or that their mothers are very close relatives.

Three-Quarter Siblings

This gets a little more complicated.

Three-quarter siblings occur when one parent is the same, and the other parents are siblings to each other.

Let’s use a real-life example.

A couple marries and has children. The mother dies, and the father marries the mother’s sister and has additional children. Those children are actually less than full siblings, but more than half-siblings.

Conversely, a woman has children by two brothers and those children are three-quarter siblings.

These were common situations in earlier times when a man needed a female companion to raise children and women needed a male companion to work on the farm. Neither one could perform both childcare and the chores necessary to earn a living in an agricultural society, and your deceased spouse’s family members were already people you knew. They already loved your children too.

Neither of these situations is historically unusual, but both are very difficult to determine using genetics alone, even in the current generation.

Neither X-DNA nor mitochondrial DNA will be helpful, and Y-DNA will generally not be either.

Unfortunately, three-quarter siblings’ autosomal DNA will fall in the range of both half and full siblings, although not at the bottom of the half-sibling range, nor at the top of the full sibling range – but that leaves a lot of middle ground.

I’ve found it almost impossible to prove this scenario without prior knowledge, and equally as impossible to determine which of multiple brothers is the father unless there is a very strong half-sibling match in addition.

The DNA-Sci blog discusses this phenomenon, but I can’t utilize comparison screenshots according to their terms of service.

Clearly, what we need are more known three-quarter siblings to submit data to be studied in order to (possibly) facilitate easier determination, probably based on the percentage frequency distribution of FIR/HIR segments. Regardless, it’s never going to be 100% without secondary genealogical information.

Three-quarter siblings aren’t very common today, but they do exist. If you suspect something of this nature, really need the answer, and have exhausted all other possibilities, I recommend engaging a very experienced genetic genealogist with experience in this type of situation. However, given the random nature of recombination in humans, we may never be able to confirm using any methodology, with one possible exception.

There’s one possibility using Y-DNA if the parents in question are two brothers. If one brother has a Y-DNA SNP mutation that the other does not have, and this can be verified by testing either the brothers who are father candidates or their other known sons via the Big Y-700 test – the father of the siblings could then be identified by this SNP mutation as well. Yes, it’s a long shot.

Three-quarter sibling situations are very challenging.

Step-siblings, on the other hand, are easy.

Step-Siblings

Step-siblings don’t share either parent, so their DNA will not match to each other unless their parents are somehow related to each other. Please note that this means either of their parents, not just the parents who marry each other.

One child’s parent marries the other child’s parent, resulting in a blended family. The children then become step-siblings to each other.

The terms step-sibling and half-sibling are often used interchangeably, and they are definitely NOT the same.

Adopted Siblings

Adopted siblings may not know they are adopted and believe, until DNA testing, that they are biological siblings.

Sometimes adopted siblings are either half-siblings or are otherwise related to each other but may not be related to either of their adoptive parents. Conversely, adopted siblings, one or both, may be related to one of their adoptive parents.

The same full and half-sibling relationship genetic clues apply to adopted siblings, as well as the tools and techniques in the In Search of Unknown Family series of articles.

Donor-Conceived Siblings

Donor-conceived siblings could be:

  • Half-siblings if the donor is the same father but a different mother.
  • Half-siblings if they share an egg donor but not a father.
  • Full siblings if they are full biological siblings to each other, meaning both donors are the same but not related to the woman into whom the fertilized egg was implanted, nor to her partner, their legal parents.
  • Not biologically related to each other or either legal parent.
  • Biologically related to one or both legal parents when a family member is either an egg or sperm donor.

Did I cover all of the possible scenarios? The essence is that we literally know nothing and should assume nothing.

I have known of situations where the brother (or brothers) of the father was the sperm donor, so the resulting child or children appear to be full or three-quarters siblings to each other. They are related to their legal father who is the mother’s partner. In other words, in this situation, the mother’s husband was infertile, and his brother(s) donated sperm resulting in multiple births. The children from this family who were conceived through different brothers and had very close (half-sibling) matches to their “uncles'” children were very confused until they spoke with their parents about their DNA results.

The same techniques to ascertain relationships would be used with donor-conceived situations. Additionally, if it appears that a biological relationship exists, but it’s not a full or half-sibling relationship, I recommend utilizing other techniques described in the In Search of Unknown Family series.

Twins or Multiple Birth Siblings

Two types of twin or multiple birth scenarios exist outside of assisted fertilization.

Fraternal twins – With fraternal or dizygotic twins, two eggs are fertilized independently by separate sperm. Just view this as one pregnancy with two siblings occupying the same space for the same 9 months of gestation. Fraternal twins can be male, female or one of each sex.

Fraternal twins are simply siblings that happen to gestate together and will match in the same way that full siblings match.

Please note that it’s possible for two of a woman’s eggs to be fertilized at different times during the same ovulation cycle, potentially by different men, resulting in twins who are actually half-siblings.

A difference in ethnicity is NOT a reliable indicator of fraternal or identical twins. Submitting your own DNA twice often results in slightly different ethnicity results.

Identical twins – Identical or monozygotic twins occur when one egg is fertilized by one sperm and then divides into multiple embryos that develop into different children. Those children are genetically identical since they were both developed from the same egg and sperm.

Two of the most famous identical twins are astronauts Mark and Scott Kelly.

Identical twins are the same sex and will look the same because they have the same DNA, except for epigenetic changes, but of course external factors such as haircuts, clothes and weight can make identical twins physically distinguishable from each other.

DNA testing companies will either identify identical twins as “self,” “identical twin” or “parent/child” due to the highest possible shared cM count plus fully matching FIR regions.

For identical twins, checking the FIR versus HIR is a positive identification as indicated above at GEDmatch with completely solid green FIR regions. Do not assume twins that look alike are identical twins.

Siblings

Whoever thought there would be so many kinds of siblings!

If you observe the need to educate about either sibling terminology or DNA identification methodologies, feel free to share this article. When identifying relationships, never assume anything, and verify everything through multiple avenues.

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So, You Want to Become a Professional Genetic Genealogist

I get asked quite often about what is required to become a professional genetic genealogist.

That’s actually two separate questions.

  • What is required to become a professional genealogist?
  • Then, what is required to specialize as a genetic genealogist?

What It’s Not

Before we have this discussion, I need to make sure that you understand that I’m NOT talking about forensics, meaning IGG, or investigative genetic genealogy in this article.

  • This is NOT forensics (IGG)
  • This is also not a specialty in finding missing parents for adoptees and others searching for unknown parents.

Both IGG and adoption searches utilize the same methodology, a subset of genetic genealogy. I wrote about that in Identifying Unknown Parents and Individuals Using DNA Matching.

The difference between genetic genealogy more broadly and IGG is:

  • What you’re searching for
  • The perspective
  • The methods utilized.

Essentially, the functional difference is that genealogists know who they are and have some information about their ancestors. For example, they know who their parents are and probably at least their grandparents. Genealogists are using both DNA testing and traditional genealogical paper trail research methods to focus and make discoveries going backwards in time.

Both IGG and unknown parent research uses DNA and (sometimes some) paper trail genealogy to find ways to connect the closest matches to the DNA tester (or DNA sample) together to each other to identify either living or recently living people. For example, two people who are are first cousins to the tester should both have the same grandparents if they are related to the tester through the same parent.

If two people who are related to the tester as first cousins do not share the same grandparent(s), then they are related to the tester through different parents of the tester.

The commonality is that DNA testing and some types of records are used for:

  • IGG where you’re searching for the identity of the tester or DNA sample
  • Unknown parent(s) searches where you are searching for the identity of the parent(s)
  • Genetic genealogy

However, the search methodology is different for IGG and unknown parents than for genealogy.

With IGG and unknown parent searches, you’re looking for your closest matches, then attempting to connect them together to identify either currently living or recently living people.

This article focuses specifically on genealogy and genetic genealogy, meaning looking backwards in time to identify ancestors.

I wrote about the techniques used for both IGG and parental searching in the article, Identifying Unknown Parents and Individuals Using DNA Matching.

What Do Genealogists Do?

Genealogy is the study of family history and the descent of a person or a family. Genealogists use a variety of sources and methods to discover and show the ancestry of their subjects and in doing so, create the family trees that are familiar to all of us.

Genealogists use different sources and methods to find and show the descent and kinship of their subjects.

Traditional sources include but are not limited to the following record types:

  • Vital records (birth, marriage, and death certificates)
  • Census
  • Military
  • Immigration
  • Land and tax records
  • Wills and probate
  • Church records
  • Newspapers
  • Obituaries
  • Published and online books
  • Oral histories
  • Genealogy databases
  • And more

Of course, today the four types of DNA can be added to that list.

A professional genealogist needs to know how and where to find these types of records in the target area, any unique cultural or regional factors affecting those records, and how to interpret them both individually and together.

For example, in a deed record in colonial Virginia, why would, or wouldn’t a female release her dower right? What is dower right, and why is it important? How might that record, or lack thereof, affect future probate for that woman/couple? In what type of historical or court record book might one look for these types of records?

Genealogists also need to know how to weigh different types of information in terms of potential accuracy and how to interpret primary and secondary sources.

Primary sources are those that were created at or near the time of an event by someone who was present at the event or who had first-hand knowledge of it. Examples of primary sources include birth certificates, marriage licenses, and census records, although census records are far more likely to be inaccurate or incomplete than a birth certificate or marriage record. Genealogists need to understand why, and where to look for corroboration. Primary sources are considered to be most accurate.

Secondary sources are those that were created later by someone who did not have first-hand knowledge of the event. Examples of secondary sources include family histories and genealogies, published biographies, and sometimes, newspaper articles.

The genealogists “go to” source for understanding and interpreting evidence is Evidence Explained by Elizabeth Shown Mills, available here.

Of course, DNA understanding and analysis needs to be added to this list and has become an important resource in genealogy. Additionally, genetic genealogy has become a specialty within the broader field of genealogy, as has IGG.

Put another way, a genealogist should have expertise and a specialty in some area. Maybe Italian records, or Native American genealogy, or New England records, in addition to the basic skills. At one time, a genealogist didn’t necessarily HAVE TO have expertise in genetic genealogy as well, but that has changed in the past few years. A professional genealogist should MINIMALLY understand the basics of genetic genealogy and when/how it can be useful. They may or may not have ready access to a genetic genealogist within the company where they work.

Being an independent genealogist, unless you specialize only in a specific area, like Dutch genealogy, is much more challenging because you’ll need to be proficient in BOTH Dutch genealogy AND genetic genealogy. It’s tough keeping up with one specialty, let alone two, although in this case, Yvette does an amazing job. However, her primary specialty is Dutch genealogy, and genetic genealogy is the booster rocket when appropriate. Genetic genealogy is not always needed for traditional genealogy, which is why genetic genealogy is a specialty skill.

In addition to all that, you also need to be proficient and comfortable with technology and a good communicator. Walking on water is also helpful:)

Job Description

So, what does the job description for a genealogist look like?

I reached out to Legacy Tree Genealogists because they are one of the largest, if not the largest genealogy research company, and they partner with 23andMe, FamilyTreeDNA, and MyHeritage. Legacy Tree has specialists in many regions and languages, in addition to six genetic genealogists on staff.

Fortunately, they have a job listing posted right now, here, with an excellent description of what is expected.

If you’re interested or wish to sign up for notifications, click here.

Understanding that this job description won’t be posted forever, I reached out to the owner, Jessica Dalley Taylor, and asked if she would send me a sample description to include in this article.

Here you go, courtesy of Jessica:

About You

It’s not easy to make each client’s experience the very best it can possibly be, and it means we can only hire an exceptional genealogist for this position. You will be a great fit if:

    • You are fluent in English and can explain your genealogy discoveries in a way that clients connect with and understand
    • You have taken at least one genetic genealogy test or administered the test of a relative
    • You have introductory genetic genealogy abilities
    • You have at least intermediate traditional genealogical research experience in any geographic locality
    • You are familiar with the repositories of the areas for which you claim expertise and have worked with them to obtain documents
    • You are passionate about genealogy and are a creative problem solver
    • You are great at working independently and hitting deadlines (please don’t overlook this line about deadlines)
    • You are comfortable with Microsoft Office suite
    • You’re familiar with genealogical technology such as pedigree software
    • You have a quiet place to work without distractions, a computer, and great internet
    • You have a strong desire to work as a professional genetic genealogist

Even better if:

    • You have a basic understanding of genetic inheritance and its application to genealogy
    • You have beginning experience with interpretation and use of genetic genealogy test results
    • You have intermediate-level genetic genealogy abilities

What you’ll be doing at Legacy Tree:

    • You’ll be learning how to use genetic testing in identifying family
    • You’ll be learning how to create high-quality research reports
    • You’ll be reading and formatting reports by professional researchers
    • You’ll be assisting with researching and writing genealogy reports
    • You’ll be performing genetic genealogy analysis under the direction of professional mentors
    • You’ll be developing advanced-level genetic genealogy skills and abilities
    • With your input, you’ll do other things as opportunities and needs arise

Please note that Legacy Tree offers both traditional genealogy services, combined with genetic genealogy, along with adoption and unknown parent searches.

As a measure of fundamental basic genetic genealogy skills, you should be able to create and teach a class like First Steps When Your DNA Results Are Ready – Sticking Your Toe in the Genealogy Water.

You should also be able to read and fully comprehend the articles on this blog, as well as explain the content to others. A very wise person once told me that if you can’t explain or teach a topic, you don’t understand it.

As luck would have it, Ancestry also posted a job opening for a genealogist as I was finishing this article. Here’s part of the job requirements.

Contractor or Employee

Please note that many companies have shifted their primary hiring strategy to utilizing contractors for not more than half time, especially now that working remotely has become the norm.

This may or may not be good news for you.

It allows the company to avoid paying benefits like insurance, vacation, leave, and retirement programs which reduces their costs. You may not need these benefits, and it may represent an opportunity for you. For others who need those benefits, it’s a deal-breaker.

Contracting may provide the ability to work part-time, but contracting probably means you need to have business management skills not required when you work for someone else. Let’s just say that I make quarterly estimated tax payments and my annual CPA bill is in the $2,000 range.

Compensation

Pay, either as an employee or contractor for a company, is a sticky wicket in this field.

First, there’s a consumer mindset, although not universal, that genealogy “should be” free. In part, this is due to search angels and a history of well-intentioned people making things free. I’m one of them – guilty as charged – this blog is free. My hourly work, however, when I accepted clients (which I DO NOT now,) was not free.

However, that “should be free” mindset makes it difficult to shift to a “pay to play” mentality when people can go on social media and get what they want for free.

Professional services are not and should not be free.

Professionals should be able to earn a respectable living. The full-time Ancestry job, posted above, with those credentials, nets out to $21.63 per hour for a 40-hour week, with a graduate degree preferred. For comparison, google other jobs and professions.

If you doubt for one second whether professional services should or should not be free, especially ones that require a bachelor’s degree or master’s, just think about what your CPA would do if you asked them to do your taxes because they have the ability, for free. Same for a doctor, lawyer, or any other professional.

People are often shocked at the rates paid to employees versus the rates charged to prospective customers. This discussion has recently gotten spicy on social media, so I’m not going to comment other than to say that when I did take private clients, which I DO NOT ANYMORE, I found it much more beneficial to operate independently than to work for a company.

However, I also had a readily recognizable specialty and an avenue to reach potential clients.

I also already had a business structure set up, and a CPA, and perhaps more important than either of those – I had medical insurance already in place.

The need for benefits is what drives many people to work for companies, which I fully understand. It’s also a big factor in why there are more female genealogists than male genealogists. Married women in the US are eligible to be covered by their spouse’s insurance, assuming the spouse has insurance through their employer.

My very strong recommendation to you is to weigh all of the factors and NEVER to find yourself without medical insurance or coverage.

If you’re going to be “self-employed,” set up a company. If you’re going to set up a company, do it properly, understand the tax ramifications of the various types of corporations and engage a competent CPA to shepherd you through the process from day 1 through taxes. They are worth every penny.

Look at various jobs in the market, review at the associated pay, get a quote for genealogy services of the type you would be providing from the various companies – and decide if this profession is really for you.

I don’t mean to be a wet blanket, just a realist.

Training and Certification

Now for the good news and the bad news.

  • There is professional training for genealogy
  • There are certifications for genealogy
  • There is no “one place” for either
  • There is no certification for genetic genealogy
  • There’s a LOT of misunderstanding and misinformation about genetic genealogy
  • Genetic genealogy changes often

You need to view your education for genealogy/genetic genealogy in the same way you’d view obtaining a college degree – plus continuing education to maintain your education and skills at a current and functional level.

And yes, all of that costs money. If you decide to work for a company, be sure to ask if continuing ed is on their dime and time, or yours.

Genealogy Training

The Board for Certification of Genealogists, BCG, allows graduates to append CG, for Certified Genealogist after their name. BCG is focused on certification of skills and is not a training platform, although they do provide some webinars, etc. It’s not a college curriculum though. Certification is the “end game” for many. Candidates must submit a portfolio for evaluation, complete in a specific timeframe, and must reapply every five years to maintain their certification.

Not all genealogists are certified by BCG, and BCG only lists references of BCG members.

In the field of Genetic Genealogy, that can be problematic because many competent and well-known people are not BCG certified. BCG does not have a genetic genealogy certification.

Lack of BCG certification does not mean that someone is not qualified, and BCG certification certainly does NOT mean or imply that the individual is competent in genetic genealogy, which has more and more become a part of almost every genealogical puzzle. If not for initial discovery, for confirmation.

There are many avenues for genealogical training, including, but not limited to:

  • Brigham Young University Family History Degree
  • NGS Home Study Course
  • Salt Lake Institute of Genealogy (SLIG)
  • Genealogical Research Institute of Pittsburgh (GRIP)
  • Boston University Certificate program
  • Genealogical Institute on Federal Records (Gen-Fed)
  • Institute of Genealogy and Historical Research (IGHR)
  • University of Strathclyde
  • University of Dundee
  • Major Conferences, including RootsTech and NGS, among others
  • Specialty conferences such as the International Conference on Jewish Genealogy (IAJGS)
  • Online conferences and conference proceedings such as Rootstech who maintains a free library of their virtual and recorded conference sessions.
  • Legacy Family Tree Webinars
  • Videos produced by major genealogy companies such as MyHeritage, FamilyTreeDNA and Ancestry, often available through their website, Youtube or both
  • Blogs and learning/help centers of the major genealogy companies

Genetic Genealogy Training

Genetic genealogy training is more challenging because there is no specific program, curriculum, or certification.

Many genetic genealogists obtained their experience as a part of genealogy over 15 or 20 years and have focused on the genetic aspect of genealogy. Several of us had a scientific background that meshed well with this field and is part of why we discovered that our passion is here.

Before I provide this resource list, I need to emphatically state that probably 95% of answers that I see provided on social media platforms in response to questions asked by people are either entirely incorrect, partially incorrect in a way that makes me want to say, “well, not exactly,” or are incomplete in a way that makes a significant difference.

I chose and choose to focus on creating educational tools and making explanations available for everyone, in one place, not one question at a time.

I began publishing my blog in 2012 as an educational tool and I’m dumbstruck by how many people just want a yes or no answer instead of learning. If one doesn’t take the time to learn, they have no idea if the answers they receive are valid, or if there’s more to the story that they are missing.

Social media can mislead you badly if you don’t have the ability to discern between accurate answers, partially accurate answers, and incorrect answers. Furthermore, opinions differ widely on some topics.

Unfortunately, because there is no genetic genealogy credentialling, there is also no “post-nominal letters,” such as CG for certified genealogist. Therefore, a novice has absolutely no idea how to discern between an expert and another overly helpful novice who is unintentionally providing incorrect or partial information.

Many of us who at one time reliably answered questions have simply gotten burned out at the same question being asked over and over, and no longer regularly engage. Burnout is real. Another issue is that askers often don’t provide enough, or accurate, information, so a significant amount of time is spent in clarifying the information around a question. Furthermore, your CPA, lawyer, and physician don’t answer questions online for free, and neither do most people who are busy earning a living in this field.

DNA educational opportunities, some of which are contained within larger conference agendas, include:

There are other blogs, of course, some of which were launched by well-known genetic genealogists but are no longer maintained. Blogging is quite time-consuming.

I’ve covered all kinds of genetic genealogy topics in my blog articles. They are a good source of information, education and hands-on training. I attempt to publish two articles weekly, and there are over 1600 available for your enjoyment.

In addition to the initial learning period, you’ll need to make time to stay engaged and maintain your genealogy and genetic genealogy skills.

Apprenticeship

In addition to training, I think you’d need at least a year interning or working at a junior learning level, minimum. Think of it as your genealogy residency.

  • You could choose to work for a vendor in their help center.
  • You could choose to work for a genealogy company. I’ve mentioned the largest ones, but there are others as well.
  • You could choose to work on your own case studies and those of your friends and family, but if you do, be aware that you won’t have anyone reviewing your work. If you make a mistake or should have approached something differently, and you’re working alone, there’s no one to tell you.
  • You could work as a search angel for others. I have mixed emotions about this, in part due to the lack of review and oversight. But also, in part because “free search angels” perpetuate the idea that genealogy “should be” free.

If you want to work in IGG, after training, an internship under an established mentor is ABSOLUTELY ESSENTIAL for a minimum of 100 or so successful closures.

Genealogists and genetic genealogists have the ethical responsibility to NOT MAKE MISTAKES when working on other people’s family. You need to know what you know, what you don’t know, when to get help, from where and with whom.

Networking Opportunity

A Facebook group named “Genealogy Jobs” has been established to discuss opportunities and all of the topics surrounding this subject.

There’s a Genealogy Career Day event on April 22nd where you can interact with professionals including authors, freelance genealogists, certified genealogists, business owners, and an investigative genetic genealogist. Take a look at the topics. If you’re considering whether or not you want to go pro, you’ll be interested. You can sign up here.

The sessions will be uploaded to their YouTube channel, here, after the event.

I hope you’ve found this article useful and helps you decide if this profession is for you. If so, create a plan and execute.

If you decide you do want to go pro, I wish you the best and welcome you to the fast-paced world of professional genealogy or its specialty, genetic genealogy.

____________________________________________________________

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X Chromosome Master Class

The X chromosome can be especially useful to genetic genealogists because it has a unique inheritance path. Thanks to that characteristic, some of the work of identifying your common ancestor is done just by simply HAVING an X match.

Unfortunately, X-DNA and X matching is both underutilized and somewhat misunderstood – in part because not all vendors utilize the X chromosome for matching.

The X chromosome has the capability of reaching further back in time and breaking down brick walls that might fall no other way.

Hopefully, you will read this article, follow along with your own DNA results and make important discoveries.

Let’s get started!

Who Uses the X Chromosome?

The X chromosome is autosomal in nature, meaning it recombines under some circumstances, but you only inherit your X chromosome from certain ancestors.

It’s important to understand why, and how to utilize the X chromosome for matching. In this article, I’ve presented this information in a variety of ways, including case studies, because people learn differently.

Of the four major testing vendors, only two provide X-DNA match results.

  • FamilyTreeDNA – provides X chromosome results and advanced matching capabilities including filtered X matching
  • 23andMe – provides X chromosome results, but not filtered X matching without downloading your results in spreadsheet format
  • Ancestry and MyHeritage do not provide X-DNA results but do include the X in your raw DNA file so you can upload to vendors who do provide X matching
  • GEDmatch – not a DNA testing vendor but a third-party matching database that provides X matching in addition to other tools

It’s worth noting at this point that X-DNA and mitochondrial DNA is not the same thing. I wrote about that, here. The source of this confusion is that the X chromosome and mitochondrial DNA are both associated in some way with descent from females – but they are very different and so is their inheritance path.

So, what is X-DNA and how does it work?

What is X-DNA?

Everyone inherits two copies of each of chromosomes 1-22, one copy of each chromosome from each of your parents.

That’s why DNA matching works and each match can be identified as “maternal” or “paternal,” depending on how your match is related to you. Each valid match (excluding identical by chance matches) will be related either maternally, or paternally, or sometimes, both.

Your 23rd chromosome is your sex determination chromosome and is inherited differently. Chromosome 23 is comprised of X and Y DNA.

Everyone inherits one copy of chromosome 23 from each parent.

  • Males inherit a Y chromosome from their father, which is what makes males male. They do not inherit an X chromosome from their father.
  • Males always inherit an X chromosome from their mother.
  • Females inherit an X chromosome from both parents, which is what makes them female. Females have two X chromosomes, and no Y chromosome.
Chromosome 23 Father Contributes Mother Contributes
Male Child Y chromosome X chromosome
Female Child X chromosome X chromosome

X-DNA and mitochondrial DNA are often confused, but they are not the same thing. In fact, they are completely different.

Mitochondrial DNA, in BOTH males and females is always inherited from only the mother and only descends from the direct matrilineal line, so only the mother’s mother’s mother’s direct line. X DNA can be inherited from a number of ancestors based on a specific inheritance path.

Everyone has both X-DNA AND mitochondrial DNA.

Because males don’t inherit an X chromosome from their father, X chromosome matching has a unique and specific pattern of descent which allows testers who match to immediately eliminate some potential common ancestors.

  • Males only inherit an X chromosome from their mother, which means they can only have legitimate X matches on their mother’s side of their tree.
  • Females, on the other hand, inherit an X chromosome from both their mother and father. Their father only has one X chromosome to contribute, so his daughter receives her paternal grandmother’s X chromosome intact.
  • Both males and females inherit their mother’s X chromosome just like any of the other 22 autosomes. I wrote about chromosomes, here.

However, the unique X chromosome inheritance path provides us with a fourth very useful type of DNA for genealogy, in addition to Y-DNA, mitochondrial and autosomal DNA.

For the vendors who provide X-matching, it’s included with your autosomal test and does not need to be purchased separately.

The Unique X Chromosome

The X chromosome, even though it is autosomal in nature, meaning it does recombine and divide in certain circumstances, is really its own distinct tool that is not equivalent to autosomal matching in the way we’re accustomed. We just need to learn about the message it’s delivering and how to interpret X matches.

FamilyTreeDNA is one of two vendors who utilizes X chromosome matching, along with 23andMe, which is another good reason to encourage your matches at other vendors to upload their DNA file to FamilyTreeDNA for free matching.

The four major vendors do include X-DNA results in their raw DNA download file, even if they don’t provide X-matching themselves. This means you can upload the results to either FamilyTreeDNA or GEDmatch where you can obtain X matches. I provided step-by-step download/upload instructions for each vendor here.

Let’s look how X matching is both different, and beneficial.

My X Chromosome Family Tree

We are going to build a simple case study. A case study truly is worth 1000 descriptions.

This fan chart of my family tree colorizes the X chromosome inheritance path. In this chart, males are colored blue and females pink, but the salient point is that I can inherit some portion of (or all of) a copy of my X chromosome from the colorized ancestors, and only those ancestors.

Because males don’t inherit an X chromosome from their father, they CANNOT inherit any portion of an X chromosome from their father’s ancestors.

Looking at my father’s half of the chart, at left, you see that I inherited an X chromosome from both of my parents, but my father only inherited an X chromosome from his mother, Ollie Bolton. His father’s portion of the tree is uncolored, so no X chromosome could have descended from his paternal ancestors to him. Therefore he could not pass any X chromosome segments to me from his paternal side – because he doesn’t have X DNA from his father.

Hence, I didn’t inherit an X chromosome from any of the people whose positions in the chart are uncolored, meaning I can only inherit an X chromosome from the pink or blue people.

Essentially any generational male to male, meaning father/son relationship is an X-DNA blocker.

I know positively that I inherited my paternal grandmother, Ollie Bolton’s entire X chromosome, because hers is the only X chromosome my father, in the fan chart above, had to give me. His entire paternal side of the fan chart is uncolored.

Men only ever inherit their X chromosome from their mother. The only exception to this is if a male has the rare genetic condition of Klinefelter Syndrome, also known as XXY. If you are an adult male, it’s likely that you’ll already know if you have Klinefelters, so that’s probably the last possibility you should consider if you appear to have paternal X matches, not the first.

Sometimes, men appear to have X matches on their father’s side, but (barring Klinefelter’s) this is impossible. Those matches must either be identical by chance, or somehow related in an unknown way on their mother’s side.

Everyone inherits an X chromosome from their mother that is some combination of the X from her father and mother. It’s possible to inherit all of your maternal grandmother or maternal grandfather’s X chromosome, meaning they did not recombine during meiosis.

Using DNA Painter as an X Tool

I use DNAPainter to track my matches and correlate segments with ancestors.

I paint my DNA segments for all my chromosomes at DNAPainter which provides me with a central tracking mechanism that is visual in nature and allows me to combine matches from multiple vendors who provide segment information. I provide step-by-step instructions for using DNAPainter, here.

This is my maternal X chromosome with my matches painted. I’ve omitted my matches’ names for privacy.

On the left side of the shaded grey column, those matches are from my maternal grandmother’s ancestors. On the right side, those matches are from my maternal grandfather’s ancestors.

The person in the grey column descends from unknown ancestors. In other words, I can tell that they descend from my maternal line, but I can’t (yet) determine through which of my two maternal grandparents.

There’s also an area to the right of the grey column where there are no matches painted, so I don’t know yet whether I inherited this portion of my X chromosome from my maternal grandmother or maternal grandfather.

The small darker pink columnar band is simply marking the centromere of the chromosome and does not concern us for this discussion.

Click on any image to enlarge

In this summary view of my paternal X chromosome, above, it appears that I may well have inherited my entire X chromosome from my paternal great-grandmother. We know, based on our inheritance rules that I clearly received my paternal grandmother’s X chromosome, because that’s all my father had to give me.

However, by painting my matches based on their ancestors, and selecting the summary view, you can see that most of my paternal X chromosome can be accounted for, with the exception of rather small regions with the red arrows.

It’s not terribly unusual for either a male or female to inherit their entire maternal X chromosome from one grandparent, or in this case, great-grandparent.

Of course, a male doesn’t inherit an X chromosome from their father, but a female can inherit her paternal X chromosome from either or both paternal grandparents.

Does Size Matter?

Generally speaking, an X match needs to be larger than a match on the other chromosomes to be considered genealogically equivalent in the same timeframe as other autosomal matches. This is due to:

  • The unique inheritance pattern, meaning fewer recombination events occurred.
  • The fact that X-DNA is NOT inherited from several lines.
  • The X chromosome has lower SNP density, meaning it contains fewer SNPs, so there are fewer possible locations to match when compared to the other chromosomes.

I know this equivalency requirement sounds negative, but it’s actually not. It means 7 cM (centimorgans) of DNA on the X chromosome will reach back further in time, so you may carry the DNA of an ancestor on the X chromosome that you no longer carry on other chromosomes. It may also mean that older segments remain larger. It’s actually a golden opportunity.

It sounds much more positive to say that a 16 cM X match for a female, or a 13 cM X match for a male is about the same as a 7 cM match for any other autosomal match in the same generation.

Of course, if the 7 cM match gets divided in the following generation, it has slipped below the matching threshold. If a 16 or 13 cM X match gets divided, it’s still a match. Plus, in some generations, if passed from father to daughter, it’s not divided or recombined. So a 7 cM X match may well be descended from ancestors further back in time.

X Chromosome Differences are Important!

Working with our great-great grandparent’s generation, we have 16 direct ancestors as illustrated in the earlier fan chart.

Given that females inherit from 8 X-chromosome ancestors in total, they are going to inherit an average of 45.25 cM of X-DNA from each of those ancestors. Females have two X chromosomes for a total length of 362 cM of X-DNA from both parents.

A male only has one X chromosome, 181 cM in length, so he will receive an average of 36.2 cM from each of 5 ancestors, and it’s all from his mother’s side.

In this chart, I’ve shown the total number of cMs for all of the autosomes, meaning chromosomes 1-22 and, separately, the X for males and females.

  • The average total cM for chromosomes 1-22 individually is 304 cM. (Yes, each chromosome is a different length, but that doesn’t matter for averages.)
  • That 304 cM can be inherited from any of 16 ancestors (in your great-grandparent’s generation)
  • The total number of cM on the X chromosomes for both parents for females totals 362
  • The total cM of X-DNA for males is 181 cM
  • The calculated average cM inherited for the X chromosome in the same generation is significantly different, shown in the bottom row.

The actual average for males and females for any ancestor on any random non-X chromosome (in the gg-grandparent generation) is still 19 cM. Due to the inheritance pattern of the X chromosome, the female X-chromosome average inheritance is 45.25 cM and the male average is 36.2 cM, significantly higher than the average of 19 cM that genetic genealogists have come to expect at this relationship distance on the other chromosomes, combined.

How Do I Interpret an X Match?

It’s important to remember when looking at X matching that you’re only looking at the amount of DNA from one chromosome. When you’re looking at any other matching amount, you’re looking at a total match across all chromosomes, as reported by that vendor. Vendors report total matching DNA differently.

  • The total amount of matching autosomal DNA does not include the X chromosome cMs at FamilyTreeDNA. X-DNA matching cMs are reported separately.
  • The total amount of matching autosomal DNA does include the X chromosome cMs in the total cM match at 23andMe
  • X-DNA is not used for matching or included in the match amount at either MyHeritage or Ancestry, but is included in the raw DNA data download files for all four vendors.
  • The total match amount shows the total for 22 (or 23) chromosomes, NOT just the X chromosome(s). That’s not apples to apples.

Therefore, an X match of 45 cM for a female or 36 for a male is NOT (necessarily) equivalent to a 19 cM non-X match. That 19 cM is the total for 22 chromosomes, while the X match amount is just for one chromosome.

You might consider a 20 cM match on the regular autosomes significant, but a 20 cM X-only match *could* be only roughly equivalent to a 10ish cM match on chromosomes 1-22 in the same generation. That’s the dog-leg inheritance pattern at work.

This is why FamilyTreeDNA does not report an X-only match if there is no other autosomal match. A 19 cM X match is not equivalent to a 19cM match on chromosomes 1-22. Not to mention, calculating relationships based on cM ranges becomes more difficult when the X is included.

However, the flip side is that because of the inheritance pattern of the X chromosome, that 19 cM match, if valid and not IBC, may well reach significantly further back in time than a regular autosomal matches. This can be particularly important for people seeking either Native or enslaved African ancestors for whom traditional records are elusive if they exist at all.

Critical Take-Away Messages

Here are the critical take-away messages:

  1. Because there are fewer ancestral lineages contributing to the tester’s X chromosome, the amount of X chromosomal DNA that a tester inherits from the ancestors who contribute to their X chromosome is increased substantially.
  2. The DNA of the contributing ancestors is more likely to be inherited, because there are fewer other possible contributing ancestors, meaning fewer recombination events or DNA divisions/recombinations.
  3. X-DNA is also more likely to be inherited because when passed from mother to son, it’s passed intact and not admixed with the DNA of the father.
  4. X matches cannot be compared equally to either percentages or cM amounts on any of the other chromosomes, or autosomal DNA in total, because X matching only reports the amount on one single chromosome, while your total cM match amount reports the amount of DNA that matches from all chromosomes (which includes the X at 23andMe).
  5. If you have X matches at 23andMe and/or FamilyTreeDNA, you can expect your total matching to be higher at 23andMe because they include the X matching cM in the total amount of shared DNA. FamilyTreeDNA provides the amount of X matching DNA separately, but not included in the total. MyHeritage and Ancestry do not include X matching DNA.

For clarity, at FamilyTreeDNA, you can see my shared DNA match with my mother. Of course, I match her on the total length of all my chromosomes, which is 3563 cM, the total Shared DNA for chromosomes 1-22. This includes all chromosomes except for the X chromosome which is reported separately at 181 cM. The longest contiguous block of shared DNA is 284 cM, the entire length of chromosome 1, the longest chromosome.

Because I’m a female, I match both parents on the full length of all 23 chromosomes, including 181 cM on both X chromosomes, respectively. Males will only match their mother on their X chromosome, meaning their total autosomal DNA match to their father, because the X is excluded, is 181 cM less than to their mother.

This difference in the amount of shared DNA with each parent, plus the differences in how DNA totals are reported by various vendors is also challenging for tools like DNAPainter’s Shared cM Tool which is based on the crowd sourced Shared cM Project that averages shared DNA numbers for known relationships at various vendors and translates those numbers into possible relationships for unknown matches.

Not all vendors report their total amount of shared DNA the same way. This is true for both X-DNA and half identical (HIR) versus fully identical (FIR) segments at 23andMe. This isn’t to say either approach is right or wrong, just to alert you to the differences.

Said Another Way

Let’s look at this another way.

If the average on any individual chromosome is 19 cMs for a relationship that’s 5 generations back in time. The average X-DNA for the same distance relationship is substantially more, which means that:

  • The X-DNA probably reaches further back in time than an equivalent relationship on any other autosome.
  • The X-DNA will have (probably) divided fewer times, and more DNA will descend from individual ancestors.
  • The inheritance path, meaning potential ancestors who contributed the X chromosomal DNA, is reduced significantly.

It’s challenging to draw equivalences when comparing X-DNA matching to the other chromosomes due to several variables that make interpretation difficult.

Based on the X-match size in comparison to the expected 19 cM single chromosome match at this genealogical distance, what is the comparable X-DNA segment size to the minimum 7 cM size generally accepted as valid on other chromosomes? What would be equal to a 7 cM segment on any other single random autosomal match, even though we know the inheritance probabilities are different and this isn’t apples to apples? Let’s pretend that it is.

This calculation presumes at the great-great-grandparent level that the 19 cM is in one single segment on a single chromosome. Now let’s divide 19 cM by 7 cM, which is 2.7, then divide the X amounts by the same number for the 7 cM equivalent of 16.75 cM for a female and 13.4 cM for a male.

When people say that you need a “larger X match to be equivalent to a regular autosomal match,” this is the phenomenon being referenced. Clearly a 7 cM X match is less relevant, meaning not equivalent, in the same generation as a 7 cM regular autosomal match.

Still, X matching compared to match amounts shown on the other chromosomes is never exact;u apples to apples because:

  • You’re comparing one X chromosome to the combined DNA amounts of many chromosomes.
  • The limited recombination path.
  • DNA from the other autosomes is less likely to be inherited from a specific ancestor.
  • The X chromosome has a lower SNP density than the other chromosomes, meaning fewer SNPs per cM.
  • The X-DNA may well reach further back in time because it has been divided less frequently.

Bottom Line

The X chromosome is different and holds clues that the other autosomes can’t provide.

Don’t dismiss X matches even if you can’t identify a common ancestor. Given the inheritance path, and the reduced number of divisions, your X-DNA may descend from an ancestor further back in time. I certainly would NOT dismiss X matches with smaller cMs than the 13 and 16 shown above, even though they are considered “equivalent” in the same generation.

X chromosome matching can’t really be equated to matching on the other chromosomes. They are two distinct tools, so they can’t be interpreted identically.

Different vendors treat the X chromosome differently, making comparison challenging.

  • 23andMe includes not only the X chromosome in their cM total, but doubles the Fully Identical Regions (FIR) when people, such as full siblings, share the same DNA from both parents. I wrote about that here.
  • Ancestry does not include the X in their cM match calculations.
  • Neither does MyHeritage.
  • FamilyTreeDNA shows an X match only when it’s accompanied by a match on another chromosome.

The Shared cM Project provides an average of all of the data input by crowdsourcing from all vendors, by relationship, which means that the cM values for some relationships are elevated when compared to the same relationship or even same match were it to be reported from a different vendor.

The Best Part!

The X chromosome inheritance pattern means that you’re much more likely to carry some amount of a contributing ancestor’s X-DNA than on any other chromosome.

  • X-DNA may well be “older” because it’s not nearly as likely to be divided, given that there are fewer opportunities for recombination.
  • When you’re tracking your X-DNA back in your tree, whenever you hit a male, you get an automatic “bump” back a generation to his mother. It’s like the free bingo X-DNA square!
  • You can immediately eliminate many ancestors as your most recent common ancestor (MRCA) with an X-DNA match.
  • Because X-DNA reaches further back in time, sometimes you match people who descend from common ancestors further back in time as well.

If you match someone on multiple segments, if one of those matching segments is X-DNA, that segment is more likely to descend from a different ancestor than the segments on chromosomes 1-22. I’ve found many instances where an X match descends from a different ancestor than matching DNA segments on the autosomes. Always evaluate X matches carefully.

Sometimes X-DNA is exactly what you need to solve a mystery.

Ok, now let’s step through how to use X-DNA in a real-life example.

Using X DNA to Solve a Mystery

Let’s say that I have a 30 cM X match with a male.

  • I know immediately that our most recent common ancestor (MRCA) is on HIS mother’s side.
  • I know, based on my fan chart, which ancestral lines are eliminated in my tree. I’ve immediately narrowed the ancestors from 16 to 5 on his side and 16 to 8 on my side.
  • Two matching males is even easier, because you know immediately that the common ancestor must be on both of their mother’s sides, with only 5 candidate lines each at the great-great-grandparent generation.

Female to female matches are slightly more complex, but there are still several immediately eliminated lines each. That means you’ve already eliminated roughly half of the possible relationships by matching another female on their X chromosome.

In this match with a female second cousin, I was able to identify who she was via our common ancestor based on the X chromosome path. In this chart, I’m showing the relevant halves of her chart at left (paternal), and mine (maternal), side by side.

I added blockers on her chart and mine too.

As it turns out, we both inherited most of our X chromosome from our great-grandparents, marked above with the black stars.

Several lines are blocked, and my grandfather’s X chromosome is not a possibility because the common ancestor is my maternal grandmother’s parents. My grandfather is not one of her ancestors.

Having identified this match as my closest relative (other than my mother) to descend on my mother’s maternal side, I was able to map that portion of my X chromosome to my great-grandparents Nora Kirsch and Curtis Benjamin Lore.

My X Chromosome at DNA Painter

Here’s my maternal X chromosome at DNAPainter and how I utilized chromosome painting to push the identification of the ancestors whose X chromosome I inherited back an additional two generations.

Using that initial X chromosome match with my second cousin, shown by the arrow at bottom of the graphic, I mapped a large segment of my maternal X chromosome to my maternal great-grandparents.

By viewing the trees of subsequent X maternal matches, I was then able to push those common segments, shown painted directly above that match with the same color, back another two generations, to Joseph Hill, born in 1790, and Nabby Hall. I was able to do that based on the fact that other matches descend from Joseph and Nabby through different children, meaning we all triangulate on that common segment. I wrote about triangulation at DNAPainter, here.

I received no known X-DNA from my great-grandmother, Nora Kirsch, although a small portion of my X chromosome is still unassigned in yellow as “Uncertain.”

I received a small portion of my maternal X chromosome, in magenta, at left, from my maternal great-great-grandparents, John David Miller and Margaret Lentz.

The X chromosome is a powerful tool and can reach far back in time.

In some cases, the X, and other chromosomes can be inherited intact from one grandparent. I could have inherited my mother’s entire copy of her mother’s, or her father’s X chromosome based on random recombination, or not. As it turns out, I didn’t, and I know that because I’ve mapped my chromosomes to identify my ancestors based on common ancestors with my matches.

X-DNA Advanced Matches at FamilyTreeDNA

At FamilyTreeDNA, the Advanced Matches tab includes the ability to search for X matches, either within the entire database, or within specific projects. I find the project selection to be particularly useful.

For example, within the Claxton project, my father’s maternal grandmother’s line, I recognize my match, Joy, which provides me an important clue as to the possible common ancestor(s) of our shared segments.

Joy’s tree shows that her 4-times great-grandparents are my 3-times great-grandparents, meaning we are 4th cousins once removed and share 17 cM of DNA on our X chromosome across two segments.

Don’t be deceived by the physical appearance of “size” on your chromosomes. The first segment that spans the centromere, or “waist” of the chromosome, above, is 10.29 cM, and the smaller segment at right is 7.02 cM. SNPs are not necessarily evenly distributed along chromosomes.

Remember, an X or other autosomal match doesn’t necessarily mean the entire match is contained in one segment so long as it’s large enough to be divided in two parts and survive the match threshold.

It’s worth noting that Joy and I actually share at least two different, unrelated ancestral lines, so I need to look at Joy’s blocked lines to see if one of those common ancestral lines is not a possibility for our X match. It’s important to evaluate all possible ancestors, plus the inheritance path to eliminate any lineage that involves a father to son inheritance on the X chromosome.

Last but not least, you may match on your X chromosome through a different ancestor than on other chromosomes. Every matching segment has its own individual history. It’s not safe to assume.

Now, take a look at your X chromosome matches at FamilyTreeDNA, 23andMe, and GedMatch. What will you discover?

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In Search of…How Am I Related to That Close Match?

My friend recently reached out to me for some help with a close match at Ancestry. Which vendor doesn’t matter – the process for figuring out who my friend is related to her match would be essentially the same at any vendor.

My friend has no idea who the match is, nor how they are related. That match has not replied, nor is any of her information recognizable, such as an account name or photo. She has no tree, so there are literally no clues provided by the match.

We need to turn to science and old-fashioned sleuthing.

This eighth article in the “In Search of…” series steps you through the process I’m stepping my friend through.

This process isn’t difficult, per se, but there are several logical, sequential steps. I strongly recommend you read through this (at least) once, then come back and work through the process if you’re trying to solve a similar mystery.

The “In Search of…” Series

Please note that I’ve written an entire series of “In Search of…” articles that will step you through the search process and help you understand how to unravel your results. If you’re new, reading these, in order, before proceeding, would be a good idea.

  • I introduced the “In Search of” series in the article, DNA: In Search of…New Series Launches.
  • In the second article, DNA: In Search of…What Do You Mean I’m Not Related to My Family? – and What Comes Next? we discussed the discovery that something was amiss when you don’t match a family member that you expect to match, then how to make sure a vial or upload mix-up didn’t happen. Next, I covered the basics of the four kinds of DNA tests you’ll be able to use to solve your mystery.
  • In the third article, In Search of…Vendor Features, Strengths, and Testing Strategies, we discussed testing goals and strategies, including testing with and uploading to multiple autosomal DNA vendors, Y DNA, and mitochondrial DNA testing. We reviewed the vendor’s strengths and the benefits of combining vendor information and resources.
  • In the fourth article, DNA: In Search of…Signs of Endogamy, we discussed the signs of endogamy and various ways to determine if you or your recent ancestors descend from an endogamous population.
  • In the fifth article, DNA: In Search of…Full and Half-Siblings we discussed how to determine if you have a sibling match, if they are a half or full sibling, and how to discern the difference.
  • In the sixth article, Connect Your DNA test, and Others, to Your Tree, I explained how to optimize your DNA tests in order to take advantage of the features offered by each our primary DNA testing vendors.
  • In the seventh article, How to Share DNA Results and Tree Access at Ancestry, I wrote step-by-step instructions for providing access to another person to allow them to view your DNA results, AND to share your tree – which are two different things. If you have a mystery match, and they are willing to allow you access, in essence “to drive,” you can just send them the link to this article that provides detailed instructions. Note that Ancestry has changed the user interface slightly with the rollout of their new “sides” matches, but I can’t provide the new interface screenshots yet because my account has not been upgraded.

Sarah – The Mystery Match

My friend, who I’ll be calling the Tester, matches Sarah (not her name) at 554 cM. At that close level, you don’t have to worry about segments being removed by Timber at Ancestry, so that is an actual cM match level. Timber only removes segments when the match is under 90 cM. Other vendors don’t remove cMs at all.

Ancestry shows the possible relationships at that level as follows:

Some of these relationships can be immediately dismissed in this situation. For example, the Tester knows that Sarah is not her grandchild or great-grandchild.

Our tester does not have any full siblings, or any known half-siblings, but like many genealogists, she is always open-minded. Both of her parents are living, and her father has already tested. Sarah does not match her father. So, this match is on her mother’s side.

It’s obvious that Sarah is not a full sibling, nor is she a half-sibling, based on the cM values, but she might be a child, or grandchild of a maternal half-sibling.

Let’s begin with observations and questions that will help our Tester determine how she and Sarah are related.

  1. It’s clear that IF this is a half-sibling descendant match, it’s on her mother’s side, because Sarah does not match our Tester’s father.
  2. The tester’s mother has six siblings, none of whom have tested directly, but three of whom have children or grandchildren who have tested.
  3. By viewing shared matches, Sarah matches known relatives of BOTH the maternal grandmother AND maternal grandfather of our tester, which means Sarah is NOT the product of an unknown half-sibling of her mother. Remember, Ancestry does not display shared matches of less than 20 cM. Other vendors do not restrict your shared matches.
  4. Ancestry does not provide mitochondrial DNA information, so that cannot be utilized, but could be utilized if this match was at FamilyTreeDNA, and partially utilized in an exclusionary manner if the match was at 23andMe.

DNAPainter

DNAPainter’s Shared cM Tool provides a nice visual display of possible relationships, so I entered the matching cM amount

The returned relationships are similar to Ancestry’s possible relationships.

The grid display shows the possible relationships. Relationships that fall outside of this probability range are muted.

The color shading is by generation, meaning dark grey is through great-great-grandparents, apricot is through great-grandparents, green is through grandparents, grey is through one or both parents, and blue are your own descendants.

Based on known factors, I put a red X in the boxes that can’t apply to Sarah and our Tester after evaluating each relationship. I bracketed the statistically most likely relationships in red, although I must loudly say, “do not ignore those other possibilities.”

Let’s step through the logic which will be different for everyone’s own situation, of course.

  • Age alone eliminates the great and half-great grandparents, aunts, and uncles. They are all deceased and would be well over 100 years old if they were living.
  • The green half relationships are eliminated because we know via shared matches that Sarah matches BOTH of the Tester’s maternal grandparent’s sides.
  • We know that Sarah is not a second cousin because second cousins match only ONE maternal grandparent’s ancestor’s descendants, and Sarah matches both of the tester’s maternal grandparents through their descendants. In other words, Sarah and our Tester both match people who descend from both of the Tester’s maternal grandmother AND grandfather’s lines, which, unless they are related, means Sarah’s closest common ancestor (MCRA – most recent common ancestor) with our Tester are either her maternal grandparents, or her mother.
  • Therefore, we know that Sarah cannot be any of the apricot-colored relationships because she matches BOTH of our Tester’s maternal grandparents. She would only be related through one of the Tester’s maternal grandparents to be related on the apricot level.
  • Sarah cannot be a full great-niece or nephew, or great or great-great niece or nephew because the Tester has no full siblings, confirmed by the fact that Sarah does not match the Tester’s father.
  • We know that Sarah is not the great-grandchild of the Tester, in part due to age, but the definitive scientific ax to that possibility is that Sarah does not match our Tester’s father. (Yes, our Tester does match her father at the appropriate level.)

We know that Sarah is somehow a descendant of BOTH of Tester’s maternal grandparents, so must be in either the green band of relationships, the grey half-relationships, or the blue direct relationships. All of these relationships would be descended from the Tester’s maternal grandparents (plural.)

We’ve eliminated the blue direct relationship because Sarah does not match the Tester’s father. This removes the possibility that the Tester’s children have an unknown great-grandchild, although in this case, age removes that possibility anyway.

This process-of-elimination leaves as possible relationships:

  • Grey band half niece/nephew and half great-niece/nephew, meaning that the Tester has an unknown half-sibling on their mother’s side whose child or grandchild has tested.
  • Green band first cousin which means that the tester descends from one of the Tester’s maternal aunts or uncles. Given that Sarah is not a known child of any of the Tester’s six aunts and uncles, that opens the possibility that her mother’s sibling has a previously unknown child. Three of the Tester’s mother’s siblings are females, and three are males.
  • Green band first cousin once removed is one generation further down the tree, meaning a child of a first cousin.

Using facts we know, we’ve already restricted the possible relationships to four.

Hypothesis and Shared Matches

In situations like this, I use a spreadsheet, create hypothesis scenarios and look for eliminators.

I worked with the Tester to assemble an easy spreadsheet with each of her mother’s siblings in a column, along with their year of birth. All names have been changed.

The hypothesis we are working with is that the Tester’s mother has a previously unknown child and that Sarah is that person’s child or grandchild.

Across the top of our spreadsheet, which you could also simply create as a chart, I’ve written the names of the maternal grandparents.

The Tester’s mother, Susie, is shown in the boxes that are colored red, and her siblings are listed in their birth order. Siblings who have anyone in their line who has tested are shown by colored boxes.

The Tester is shown in red beneath her mother, Susie, and a potential mystery half-sibling is shown beneath Susie.

This is importantthe relationships shown are FROM THE PERSPECTIVE OF THE TESTER.

This means, at far left, with the red arrow, these people at the top, meaning the mother’s siblings are the Tester’s aunts and uncles.

The next generation down are the Tester’s first cousins, followed by the next row, with 1C1R. The cell colors in that column correspond to the DNAPainter generation columns.

In the red “Mother” group, you’ll see that I’ve included that mystery half-sibling and beneath, the relationships that could exist at that same generation level. So, if the mystery half-sibling had a child, that person would be the half-niece/nephew of the Tester.

The cM value pointed to by the arrows, is the cM value at which the TESTER matches that person.

In this case, Ginger’s son, Jacob matches our Tester at 946 cM, which is exactly normal for a first cousin. Ginger’s son, Aaron, has not tested, but his daughter, Crystal, has and matches our Tester at 445 cM.

Three of the Tester’s aunts/uncles, John, Jim, and Elsie are not represented in this matrix, because no one from their line has yet tested. The Tester has contacted members of those families asking if they will accept a testing scholarship.

Analysis Grids

Some of the children of our Tester’s aunts/uncles have tested, and their matches to Sarah are shown in the bottom row in yellow, on the chart below.

Of course, obtaining Sarah’s matching cM information required the Tester to contact her aunts/uncles and cousins to ask them to look at their match to Sarah at Ancestry.

For each set of relationships with Sarah, I’ve prepared a mini-relationship grid below Sarah’s matches with one of the Tester’s aunts/uncles’ descendants.

  • If Sarah is related to the Tester through an unknown half-sibling, Sarah will match the tester more closely than she will match any of the children of the Tester’s aunts and uncles.
  • If Sarah descends through one of the Tester’s aunts’ or uncles’ lines, Sarah will match someone in those lines more closely than our Tester, but we may need to compensate for generations in our analysis.

I pasted the DNAPainter image in the spreadsheet in a convenient place to remind myself of which relationships are possible between our Tester and Sarah, then I created a small grid beneath the Tester’s match to Sarah, who is the yellow row.

Let me explain, beginning with our Tester’s match to Sarah.

Tester’s Match to Sarah

The Tester matches Sarah at 554 cM, which can potentially be a number of different relationships. I’ve listed the possible relationships with the most likely, at 87%, at the top. I have not listed any relationships we’ve positively eliminated, even though they would be scientifically possible.

I can’t do this for our Tester’s Uncle David, because the Tester has not yet heard back from David’s son, Gary, as to how many cMs he shares with Sarah.

Our tester’s aunts, Ginger and Barbara do have descendants who have tested, so let’s evaluate those relationships.

Ginger and Sarah

We know less about Ginger and Sarah than we do about our Tester and Sarah. However, many of the same relationship constraints remain constant.

  • For example, we know that Sarah matches both of Ginger’s grandparents, because Ginger is our tester’s aunt, Susie’s full sibling.
  • Our tester and all of the other family members who have tested match on both maternal grandparents’ sides.
  • Therefore, we also know that the 2C relationships won’t work either because Sarah matches both maternal grandparents.
  • Based on ages, it’s very unlikely that Sarah is a great-grandchild of Ginger’s children, in part, because I’m operating under the assumption that Sarah is old enough to purchase her own test, so not a child. Ancestry’s terms of service require testers to be 18 years of age to purchase or activate a DNA test. Also, Sarah’s test is not managed by someone else.
  • We don’t know about great-nieces and nephews though, because if one of Ginger’s sibling’s children had an unknown child, that person could be Sarah or Sarah’s parent.

Ginger’s son Jacob

Using the closest match in Ginger’s line, her son Jacob, we find the following possibilities using Jacob’s match to Sarah of 284cM.

The DNAPainter grid shows the more distant relationship clearly.

You can quickly determine that Sarah probably does not descend from Ginger’s line, but let’s add this to our spreadsheet for completeness.

You can see that the MOST likely relationship, of the possible relationships based on our known factors, is 1C2R, which is the least likely relationship between our Tester and Sarah. It’s important to note that our Tester and Jacob are in the same generation, so we don’t need to do any compensating for a generational difference.

Comparing those relationships, you can see that the least likely relationship between Sarah and Jacob is much more likely between Sarah and our Tester.

Therefore, we can rule out Ginger’s line as a candidate. Sarah is not a descendant of Ginger.

Let’s move on to Barbara’s line.

Barbara’s Daughter Cindy

This time, we’re going to do a bit of inferring because we do have a generational difference.

Barbara’s granddaughter, Mary, has tested and matches Sarah at 230 cM. While we know that Sarah probably wouldn’t match Mary’s mother, Cindy, at exactly double that, 460 cM, it would certainly be close.

So, for purposes of this comparison, I’m using 460 cM for Sarah to match Cindy.

That makes this comparison in the same generation as Ginger and our Tester to Sarah. We are comparing apples to apples and not apples to half an apple (an apple once removed, technically, but I digress.) 😊

You can see that this analysis is MUCH closer to the cM amounts and relationship possibilities of Sarah and our Tester.

Here are the possible relationships of Sarah and Cindy, with the most likely being boxed in red.

Where Are We?

Here is my completed spreadsheet, so far, less the two DNAPainter graphs for Ginger and Barbara’s lines.

To date, we’ve eliminated Ginger as Sarah’s ancestor.

Both Susie, the mother of our Tester, and Susie’s sister Barbara are still candidates to have an unknown child based on DNA, or one of their children possibly having an unknown child.

Of course, we still have one more sister, Elsie, and those three silent brothers sitting over there. It’s much easier for a male to have an unknown child than a female. By unknown, in this situation, I mean truly unknown, not hidden.

What’s Needed?

Of course, what we really need is tests from each of Susie’s siblings, but that’s not going to happen. What can we potentially do with what we have, how, and why?

Our Tester can refine these results in a number of ways.

  • Talk to living siblings or other family members and tactfully ask what they know about the four women during their reproductive years. Were they missing, off at school, visiting “aunts” in another location, separated from a spouse, etc.?
  • Check to see if Sarah shared her ethnicity results (View match, then click on “Ethnicity.”) If Sarah has a significant ethnicity that is impossible to confuse, this might be significant. For example, if Sarah is 50% Korean, and one of Susie’s brothers served in Korea, that makes him a prime candidate.
  • If possible, ask John, David, Jim, Ginger, Barbara, and Elsie to take DNA tests themselves. The best test is ALWAYS the oldest generation because their DNA is not yet divided in subsequent generations.
  • If that’s not possible, find a child or grandchild of Elsie, Jim, and John to test.
  • The Tester needs to find out how closely David’s son, Gary matches Sarah, then perform the same analysis that we stepped through above.
  • Ask Ginger’s son, Jacob to see if Sarah also shares matches with the closest family members of the known father of Ginger’s children. One of Ginger’s children could have had an unknown child. This is unlikely, based on what we’ve already determined about Sarah’s match level to Jacob, but it’s worth asking.
  • Ask Barbara’s granddaughter, Mary, to see if she and Sarah share matches with the closest family members of the known father of Barbara’s children. This scenario is much more likely.
  • If the answer is yes to either of the last two questions, we have identified which line Sarah descends from, because she can only descend from both Barbara AND the father of her children if Sarah descends from that couple.
  • If the answer is no, we’ve only eliminated full siblings to Ginger and Barbara’s children, not half-siblings.
  • If our Tester can make contact with Gary, ask him if he and Sarah share matches with David’s wife’s line. One of David’s children could have an unknown child.
  • If our Tester can actually make contact with Sarah, and if Sarah is willing and interested, our Tester can create a list of people to look for in her matches – for example, the spouses’ lines of all of Susie’s siblings. If Sarah matches NONE of the spouses’ lines, then one of Susie’s siblings (our Tester’s aunts/uncles,) or Susie’s mother, has an unknown child. However, if Sarah is a novice tester or genealogist, she might well be quite overwhelmed with understanding how to perform these searches. She may already be overwhelmed by discovering that she doesn’t match who she expected to match. Or, she may already know the answer to this question.
  • It would be easier if Sarah granted our Tester access to her DNA results to sort through all of these possibilities, but that’s not something I would expect a stranger to do, especially if this result is something Sarah wasn’t expecting.

I wrote instructions for providing access to DNA results in the article, How to Share DNA Results and Tree Access at Ancestry.

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I receive a small contribution when you click on some of the links to vendors in my articles. This does NOT increase the price you pay but helps me to keep the lights on and this informational blog free for everyone. Please click on the links in the articles or to the vendors below if you are purchasing products or DNA testing.

Thank you so much.

DNA Purchases and Free Uploads

Genealogy Products and Services

My Book

Genealogy Books

Genealogy Research