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Louis Kessler's Behold Blog

Triangulation does NOT mean IBD - Mon, 25 Sep 2017

When I was first learning about autosomal DNA analysis, just over a year ago, I was under the misconception that if three people triangulate on a segment, then that segment is IBD (Identical by Descent).

A segment that is IBD is one that is passed down from a common ancestor. These are the segments you are looking for. By identifying people who received the same IBD segment, you can use traditional genealogical research to trace back and figure out who was the common ancestor. This is way autosomal DNA analysis and genealogical research can work together to extend your family.

Triangulation means that Person A matches Person C on the segment, Person B matches Person C on the segment AND Person A matches Person B on the segment. If other people also triangulate with them over the same segment, then all people must match all the other people on the segment. Under this condition, all the matching people are said to be in the same triangulation group for this segment. If the segment is IBD, then they all share a common ancestor who has passed them that segment or some portion of that segment.

In a Chromosome Browser, if you are Person A, what you see is:


So you as Person A match Person C, and you as Person A also match Person B over the same segment. Don’t make the mistake of thinking that this means you triangulate with Persons B and C. You still have one more check to make. You must verify that Person B matches with Person C on that segment before you can say that the three of you triangulate. Unfortunately, your own Chromosome Browser will not tell you that.

Simply using what’s called ICW (In Common With) is not good enough. That means Person B and Person C are considered a match with each other. They definitely match on some segments, but those matches might not be the one specific segment you are looking at.

If you are at GEDmatch, you can do a one-to-one check of Person B against Person C and see if they match on the segment. At Family Tree DNA, you must ask either Person B or Person C to check in their Chromosome Browser to see if they match each other on the segment. At 23andMe, the “Y” indicator will tell you if you and a second person triangulate on at least one segment with a third person and then you can set one of them as the primary person in their Chromosome Browser and see if they match each other on the segment.

A Chromosome Browser does what I call “Single Matching”. It compares one person to all that person’s matches. By comparison, “Double Matching” uses the matches of two people and combines them and doing so can find all the triangulations that those two people have between them. It’s like having two Chromosome Browsers side-by-side:


Using double matching, you can tell that Person A matches Person C (orange) and that Person B matches Person C (green) and that Person A matches Person B (blue) all on the same segment. This is what Double Match Triangulator does for you.

That’s how you can find if people triangulate on a segment. Now what can you say if you have a triangulating segment?

My misconception a year ago was thinking that segments that triangulate are all Identical by Descent and thus the People who triangulate must share the common ancestor who passed the segment down. Debbie Kennett took a fair bit of her personal time back then through a number of emails and explained to me that this was not necessarily true. Thank you, Debbie, for your time and patience. My misconception has been corrected.

Here are the correct rules and what you need to know:

All IBD (Identical by Descent) segments will triangulate.
Some segments that Triangulate are not IBD

This is very important, especially the 2nd statement. Never assume that a triangulation is IBD. Here are a couple of reason why they may not be:


1. One of the People Match by Chance

A matching segment in a Chromosome Browser means that we half-match. Each line the Chromosome Browser shows actually represents a pair of chromosomes, one from your father and one from your mother. To be IBD, one of your parental chromosomes must match just one of Person B’s parental chromosomes and just one of Person C’s parental chromosomes. What can happen instead is that they match by “zigzagging back and forth” between the parental chromosomes. Check out the section “False Positive or Identical by Chance Match” in the article Concepts – Segment Size, Legitimate and False Matches by Roberta Estes who explains this very well.

You could theoretically have 3 people who all match each other zigzagging back and forth between their parental chromosomes. But this is quite unlikely, since instead of just one chance match, for this you need three chance matches. I haven’t seen any studies of this but my reckoning would be that it would be a rare event.

Still, there’s a much more likely way for a triangulation to happen with a chance match. Let’s say a segment of Person A matches Person B the correct way: over just one of their parental chromosomes. Then that segment of DNA is effectively the same for both of them (only differing because of a few no-calls, misreads and/or mutations). Person C may triangulate with them on this segment by zigzagging between its parental chromosomes to match at each location. If Person C matches by chance to Person A on this segment, then Person C will also match by chance to Person B.  This appears to be a triangulation but is a match by chance and is therefore not IBD.

This match by chance in a triangulation is bad because it is difficult to discern the people who are by chance matching into a triangulation group. The by chance match will match everyone else in the triangulation group. The only way to tell the difference would be to look and compare the raw data – not a simple task, and something you can’t do at GEDmatch because they don’t give you access to the raw data.

One thing triangulation does do for you is reduce the likelihood of a by chance match. In Single Matching, any match between two people that is less than about 15 cM may be a match by chance. As the segment gets smaller, the likelihood of a match by chance increases. But in triangulation, we do have one leg matching two of the people on one of their parent’s chromosome. The by chance match can zigzag on its own pair of chromosomes, but cannot zigzag on the other connection.

That forced connection reduces the worry of matches by chance but do not eliminate it. Jim Bartlett has concluded that all triangulations of 7 cM or more cannot be chance matches. He suspects that threshold might even be as low as 5 cM.

So triangulations could still include a match by chance. Be wary of triangulations under 7 cM.


2. Matching Segments are on Different Parental Chromosomes

This one really caught me off guard. I think it was in January during a discussion about triangulation on Facebook in a DNA discussion group, Blaine Bettinger posed the question to me:  What if the three matches of the triangulation are on different parental chromosomes?

That threw me for a loop. I had never thought of that before. Blaine was right. It could happen. Let’s say person A matches person C on one specific segment on his father’s chromosome, but matches person B on the same segment on his mother’s chromosome. Person B and C would likewise have to match the same way, on the opposite parental chromosome than they do with Person A.


In the above diagram, all three people match each other on the same segment.  This is a Triangulation. Person A matches Person B on the same segment (albeit different parental chromosome) as Person A’s match with Person C and person B’s match with Person C.

When Blaine first brought this up, I had a bit of a panic attack. My entry of Double Match Triangulator in the Innovator Showdown at RootsTech was coming up. This was at the time a new technology based on triangulation … and if we’ve just discovered that triangulation didn’t work, then what?

Fortunately, this turned out not to be a concern. This was just another case like the match by chance situation, where a triangulation occurs but the segment is not Identical by Descent. It does not invalidate triangulation as a tool, and triangulation is still required (but is not sufficient) for a segment to be Identical by Descent.

Don’t think these opposite parent triangulations are a rare thing. They likely are not. I’ve found a number of examples in some of the work I’ve done. And here’s the bad thing about them. It could happen with segments of any length. There is no protection by using only large segments, say 15 cM or more.

So then I thought of how to eliminate this possibility of elimination of opposite parent triangulations. Redrawing the Person A, B and C matches as a diagram, we have this:


To prevent this, all we need is a 4th person who is part of the triangulation group. When you add that 4th person, and try to connect them to each of the other three, as below:


you’ll see there is no possible way that you can make that last connection (the dashed red line) without forcing each line to be an identical segment. For example, in the above diagram, we can logic that:

A Pat = C Pat
A Mat = B Mat
B Pat = C Mat
D Mat = A Pat = C Pat = D Pat
    so D’s parental segments would match each other,
C Pat = D Pat = B Pat = C Mat
    so C’s parental segments would match each other,
C Pat = C Mat = D Pat = D Mat = A Pat = B Pat
    so all people match on an identical segment

IOW, to force the triangulating segments to match, we need 4 people in the triangulation group. This could be done with an extension to Double Match Triangulation that could awkwardly be called: Triple Match Quadrangulation, which would use the segment matches of 3 people (Person A, B and C) to find all the people D who match A, B and C where A, B and C also match each other.

An alternative that would be simpler is to do two sets of Double Match Triangulations (A with B, and  A with C) and combine the results. Doing so would avoid the need to ever have to use the word “quadrangulation”.

Double Match Triangulator already allows two or more sets of Double Matches to be combined in a “By Chromosome” run, but it does not yet merge the triangulation groups together. I’ll attempt to do so in a future version of DMT using this new knowledge that a 4th person in the group can guarantee that its the same segment that’s being triangulated.


Remember: Triangulation is still Very Useful

Even though triangulations may match by chance, or may triangulate on opposite parental chromosomes, that only means that triangulations are not necessarily Identical by Descent.

Despite this, what triangulating does for you is remove from your consideration a very large number of single matches that cannot be IBD. The matches that remain that triangulate are the only ones from which IBD segments will be found.

Said another way:  Identical by Descent segments must triangulate, so by triangulating you are greatly reducing the matches you have to look through to find the common ancestors of your DNA relatives.

Just be wary. Don’t assume all your triangulations are IBD.


Update Sept 25:  Ann Turner informed me on the ISOGG Facebook group that 23andMe allows you to put anyone as the primary person in the Chromosome Browser, so you can determine by yourself if Person B matches Person C without having to contact them. I’ve now corrected that in my article.

Additional notes in my reply to Ann:

From a mathematical analysis, I am pretty sure you would only need 3 people’s matches, A, B & C to triangulate an unlimited number of people: D, E, F, G, …. into the same triangulation group (which is what I horribly named: Triple Match Quadrangulation). Using only two people, A & B, will determine all the triangulations, but those might include some triangulations with matching segments on different paternal chromosomes.

So no, you wouldn’t need to compare D & E. If you add F, you wouldn’t need to compare D & E, D & F or E & F.  Etc.

What you will find, however, is that some people may not have enough total cM to make a match criteria. They may match just on a few small segments including the one of interest. But you can’t tell because they are not an overall match for you. You will then need to match them on the segment with a third person from the triangulation group to prove that they belong.

The IAJGS Conference 2017 - Mon, 31 Jul 2017

I’ve returned from Orlando after the week-long #IAJGS2017 (International Association of Jewish Genealogical Societies) Conference on Jewish Genealogy. This was my 8th International genealogy conference, my first being RootsTech 2012, but it was my first IAJGS Conference.

37th IAJGS Conference

The venue was The Swan Resort, ideally situated midway and within walking distance of Epcot and Hollywood Studios at Disney World, Florida. A mid-July visit to central Florida means 88F (32C) days with high humidity and thunderstorms possible at any time. So the hotel and Conference Centre compensate with powerful air conditioning that dresses up attendees in long sleeves, slacks, and even sweaters and jackets.

Front of Swan Hotel from across the canal

The Conference facility was just the right size to handle the 900 attendees, 9 different tracks, an exhibit hall, a computer workshop room, a resource room with computers giving access to paid services for free, and a mentors area. It was in a separate wing of the hotel, so the conference attendees had the whole area to ourselves.

Swan Hotel Conference Centre for IAJGS



I arrived late Saturday night, so I picked up my Conference Package Sunday morning. I loved the name tags, which prominently displayed up to 5 ancestral surnames and places. It was a no-brainer to compare them whenever meeting someone for the fist time, or for the tenth time. I added my own ribbons at the bottom and I got the ProGen ribbon at our Thursday BOF meeting. The penguin sticker was from Banai Feldstein and I’ll say more about that below.

My IAJGS Conference Badge

The Conference had an App the same as the RootsTech App. You could plan the events you wanted to go to, view the Twitter #iajgs2017 feed, see the list of speakers and attendees, invite them to be friends, view all the handouts, etc. Since I have a Windows Phone, I had to use the online version with wifi. The wifi was good in the main areas, but was a bit spotty in some of the conference rooms. Due to extensive use during the conference, my phone battery would typically run out midday. so I’d then whip out my backup phone and start with that. By Wednesday, I started carrying a charging cable and plug in my back pocket.


Sunday started with a New Attendee Welcome. As this was my first IAJGS, I decided to go to it. Two of the conference co-chairs, Dennis Rice and Adam Brown presented and led the discussion.

Dennis Rice, inset: Adam Brown and Dennis Rice

Arriving late about 9:30 a.m. I heard the end of Shelley Talalay Dardashti talk describing DNA matching at MyHeritage:

Shelley Talalay Dardashti

At10:30, I listened to Bennett Greenspan tell us about Family Tree DNA. My notes from his talk included him saying: “There will be some new tools coming out in the next quarter or two, like triangulation.” Also of interest to me, he said “If you have 4 Ashkenazi grandparents, you’ll have 12,000 matches matching to 3/4 of all Ashkenazi Jews who have tested.” I was always curious about this. Bennett’s statistics implies there are about 16,000 Ashkenazi who have tested at Family Tree DNA. That implies that a 100% Ashkenazi with 12,000 matches should have a Pickholtz-Diamond Index at Family Tree DNA of about 20. I also wrote this in my notes:  How often do you get the owner of a company talking with such passion about a topic?

Bennett Greenspan

At 1:30 pm was a presentation I was really looking forward to. My mother’s mother comes from a family of 17, and I had always heard that 14 of them were killed towards the end of WWI. I found that odd. What was going on in Ukraine during WWI that I didn’t know about? It was well before the Holocaust, and after most of the pogroms in Eastern Europe that prompted my ancestors to emigrate to Canada in the early 1900’s. I had never found out more about that, until now.

“My Dear Children” is a historical documentary being produced about the anti-Jewish massacres in Eastern Europe from 1917 to 1921. LeeAnn Dance, the producer of the film, spoke to us about it and presented clips from the upcoming production. As many as 250,000 Jews were wiped out in this massacre. Expected release is in October on PBS.

My Dear Children

LeeAnn Dance being introduced by Alex Dunai

I took the rest of the afternoon to wander around the Exhibit Hall. It was small compared to other larger conferences I’ve been at, but all the major players were there. I took some pictures of their booths.

Family Tree DNA:
Family Tree DNA booth at IAJGS 2017

RootsMagic (Bruce Buzbee and his wife Laurie):
RootsMagic booth at IAJGS 2017

Ancestry / AncestryDNA:
Ancestry booth at IAJGS 2017

Family Tree Maker (Jack Minsky and Mark Olson):
Family Tree Maker booth at IAJGS 2017

MyHeritage / MyHeritage DNA:
MyHeritage booth at IAJGS 2017

Geni booth at IAJGS 2017

JewishGen booth at IAJGS 2017

IAJGS booth at IAJGS 2017

In the evening at 7:30 p.m. was the first Keynote. Swan 1, 2 and 3 were combined for the Keynotes. There was quite a crowd there for each keynote session:
Awaiting the Sunday keynote at IAJGS 

Marlis Humphrey, the IAJGS President greeted the crowd and gave some interesting statistics: This conference has 900 attendees, 225 first timers (that includes me!). 200 have attended 5 IAJGS conferences. 100 have attended 10 or more. This conference has the most extensive DNA track ever at an IAJGS Conference. 10% of the attendees are from overseas. 34 states are represented. This is the first ever IAJGS conference in Florida. More than 25 attendees from Florida.

Daniel Horowitz then came out and prior to introducing the speaker, talked about MyHeritage who was the sponsor of this keynote. Of interest, I noted he said that the following were coming at MyHeritage DNA:  Pedigree charts, a chromosome browser, and matches by place.

The keynote was Professor Robert Watson who gave an interesting perspective on Alexander Hamilton and how his life connected to the Jews of the Caribbean island of Nevis:
Sunday keynote poster IAJGS 2017Professor Robert Watson IAJGS 2017

Following the keynote, I was accosted by a couple of penguins, who had announced earlier that all 7 continents were being represented. Banai Feldstein and Ron Arons (and a number of others who I don’t have pictures of) represented the Antarctica Jewish Genealogical Society, which has a private Facebook group that they graciously allowed me to join:
Ron AronsBanai Feldstein and Ron Arons



Bright and early at 8:15, was my computer workshop on Double Match Triangulation. It was in Swan 8, a conference room with chairs behind rows of tables so people had a place for their laptops or pads, and it had its own wifi. But there were no computers in the room. I had about 30 attendees and I knew prior that about 8 of them would need a computer for the workshop because DMT currently only runs on Windows. We were expecting Windows laptops to be supplied to those who needed them, but they turned out to be Chromebooks that won’t run DMT, so we had to make do.

Sandy Aaronson introduced me and helped the workshop attendees when they had problems. Sandy had assisted me early on in the testing of DMT last summer, and provided me with a lot of feedback that helped in its development. I communicated extensively with Sandy over the past year, so it was nice to finally meet her in person.

I was unexpectedly surprised to see Bennett Greenspan in the 3rd row with his computer. He hadn’t registered, but there certainly wasn’t anyone who was going to tell him he couldn’t attend. Bennett was genuinely interested in what I was doing.

It’s difficult to give a workshop when there are different people at different levels. You just have to just keep it rolling so that everyone can learn within the 90 minutes what you wanted them to know how to do. This was my first ever workshop/presentation on DMT, so it was very nice to have a half-dozen of the participants come up to me later at the conference to say how much they enjoyed my workshop.


The workshop was scheduled to run until 9:45 a.m. Sandy and I stayed another hour to answer questions and provide additional help to those who wanted.

This workshop was my only personal commitment to the conference. It was nice to be scheduled early so that I now had 3 full days to enjoy freely. There weren’t any talks for a while that I just had to see, so I took a few hours to get some lunch, walk around the Swan/Dolphin resort, walk to the Boardwalk area to the Epcot entrance, back all the way to the Hollywood Studios entrance, and back to the hotel. Ended up that day with 18,874 steps.

For the afternoon and evening, I picked a few DNA sessions. At 3:30 pm was “What Y-DNA Lineages Can Tell Us About Jewish History and Migration” with Rachel Unkefer, Adam Brown, Michael Waas and Janet Akaha on the panel.

Rachel Unkefer, Adam Brown, Michael Waas and Janet Akaha

Following the panel discussion, they asked for questions and I supplied one. I asked whether Y-DNA has discovered connections to any of the 10 lost tribes of Israel. I said that several years ago, Simcha Jacobovichi, an Israeli-Canadian historical documentary film-director, did a movie on the Quest for the Lost Tribes, where he claims to have found many of them. Adam Brown’s answer to me was that only one tribe has so far shown Y-DNA connections (I forget which one he said) and he classified the connections of the other tribes as fiction. Interesting.

The other movie of Simcha’s that I really like is The Exodus Decoded which attempts to plausibly explain the ten plagues and then there’s his claim of finding the true Mount Sinai. Great stuff! Watch them for yourself and make your own judgements.

At 5 p.m. was “The DNA of the Jewish People” given by Bennett Greenspan. This was a very interesting exposition about a fight that Bennett is fighting to help refute “The Thirteenth Tribe”, a 1976 book by Arthur Koestler claiming that Ashkenazi Jews are not descended from Judea, but are Khazars, a Turkic people. Koestler, of course, proposed this to dispute Jewish people’s claim to Palestine. Bennett is out to disprove this through DNA analysis. To summarize Bennett’s task, he used a saying of Ronald Coase: “If you torture data long enough, it will confess.”

Bennett Greenspan

Following Bennett’s talk, I was conversing with Karen Schlussel who I found out was a cousin of Bennett’s. Bennett came up to the two of us and said he was very interested in learning more about my double matching technique. So the three of us went out for dinner together.

Bennett had to rush back for the evening keynotes who he was introducing. The evening talk was “The Contested Origins of Ashkenazic Jews in Eastern Europe” so it was in effect a continuation of Bennett’s quest. This time, we were getting the research details that scientifically refute Koestler from the respected scholars: Dr. Alexander Beider of Paris and Dr. Harry Ostrer of New York.

Adam Brown, Dr. Harry Ostrer, Dr. Alexander Beider, Bennett Greenspan



I was up early for the Tracing the Tribe breakfast. This was a meeting of people who frequent the Facebook group for Jewish Genealogy. It has over 16,000 members. Schelly Talalay Dardashti, who is the moderator of the group, led the breakfast discussion about how to form your own Facebook groups for a specific town or surname, along with essential moderator and guideline issues.

Unfortunately, the TTT breakfast conflicted with the Blogger’s Brown Bag Breakfast which I also would have liked to attend. Emily Garber writes about the Blogger’s breakfast that I missed at the beginning of her Day 3 blog.

At 8:15 a.m., I attended the Q & A on Ashkenazi Surnames with Dr. Alexander Beider, who was one of the keynotes the night before. Dr. Beider told us that surnames can Monogenetic (only one person took the surname) and Polygenetic (multiple people took the surname). What we were all looking forward to was to write our surnames we had questions about on a slip of paper, and then he picked them up one by one and said what he knew of that surname’s origin and meaning. In my case, I asked him a pressing question I had as to why I have a couple of cases Focsaner/Zvoristeaneau and Segal/Hertzan that two brothers took different surnames. Unfortunately he didn’t have the answer for me. He generously gave us his email address in case we had further surname questions. If you haven’t already, be sure to check out Dr. Beider’s book: A Dictionary of Jewish Surnames from the Russian Empire as well as his other books. They are expensive to purchase for yourself, but you should find many of them in any major library. (Note: Dr. Beider did not push or mention any of his books during any of his talks. The mention is mine and mine alone.)

I went into the Exhibit Hall, and caught conference co-chair Adam Brown at his Avotaynu DNA booth. The Avotaynu DNA project is to foster academic studies illumination the history of the Jewish people. So I let Adam include me in the project. Then I spent some time talking to Bruce Buzbee of RootsMagic and his wife Laurie. Dick Eastman joined us for some more interesting conversation.

The rest of the day was basically what I’m calling “Ukraine Day” for me. The Ukraine SIG (Special Interest Group) had a series of talks starting at 9:45. My whole mother’s side as well as my wife’s side comes from Ukraine. I’ve never explored the Ukraine SIG before so this would be my initiation.Janette Silverman, Ukraine SIG coordinator and JewishGen’s volunteer of the year, gave the SIG 101 introduction.

Janette Silverman

Next up at 11:15 was Ukraine SIG 102 with more about the SIG brought to us Janette with the help of Joel Spector, Volunteer’s Director, and Chuck Weinstein, Towns Director.

Joel Spector, Janette Silverman, Chuck Weinstein

Not skipping a beat, we then met at 12:30 for the Ukraine SIG Luncheon. The featured speaker was Phyllis Berenson who gave a fascinating slide show about her two recent trips to Ukraine, visiting her ancestral towns. Alex Dunai who was Phyllis’ highly recommended guide, was in attendance.

Phyllis Berenson

After lunch, at 2:00 pm, we all got together again for the Ukraine SIG annual meeting, where first Janette, and then each of the Directors reported on what has happened under their jurisdiction during the year and what is coming. Below is Lara Diamond, Projects Director for Ukraine SIG, telling us how to become a project coordinator.

Lara Diamond at the Ukraine SIG annual meeting

Some of my notes from these Ukraine sessions were:
- Do a town search to identify your towns.
- If no town coordinator, then you should volunteer. It’s not much work.
- Projects need to be funded, translated and indexed.
- Most records are in Russian.
- The Ukraine archives do not allow posting of documents
- Only way to see original documents is to be a coordinator or translator
- Once documents are indexed, the originals will no longer be available
- If you find one you want, you will have to purchase it from the archives.

There was a session unfortunately scheduled at the same time as the Ukraine SIG meeting, about Volynia, a province in the Ukraine. Fortunately, the Conference coordinators were informed about this and the session was changed to 3:30 pm. I attended and it was a presentation by Alex Denysenko, a researcher from Volynia who could locate records in the archives for you. He says most cemeteries in Volynia are in terrible condition and had examples in his slides. It does sound like there might be Mezhirichi documents, so that’s encouraging for me.

Alex Denysenko

To top off the day, 12 members of our Jewish Ancestry in Volhynia District Facebook Group met at 6:45 for a Dinner together at the Garden Grove Restaurant in our Swan Hotel. Thanks go to Gary Gershfield for arranging this. We all had a wonderful time. To my surprise and delight, I did not realize that this resort or this restaurant had character dining. I did not hesitate to get the necessary pics.

The Volhynia Facebook group

Me and GoofyPluto and Me

I also saw Bruce and Laurie Buzbee at the Garden Grove and got to talk to them again.



At 8:15 was the Computer Workshop: Getting Started with GEDmatch. The person originally scheduled to give the workshop, Rebecca Canada, ended up being unable to make it to the conference. So Sandy Aaronson was asked to lead the workshop in her place. Sandy, who assisted me during my workshop, asked if I would do so during hers, and of course I accepted. It was also a sneaky way for me to get into a GEDMatch workshop which I hadn’t signed up for.

The workshop ended at 9:45. I then had plans to join my younger daughter, who was working for the summer at Disney World through their Disney College Program. We went to Epcot and had lunch together at the Coral Reef Restaurant in the Living Seas attraction.

An amazing day with Dad at Epcot :) Thanks for visiting - now back to work and conference! And see you again in a week and 2 days once I'm home!

I got back in time to join the Romania SIG meeting at 5:00 p.m. Daniel Horowitz of MyHeritage led the meeting. I didn’t realize Daniel had any Romanian in him, but in fact he shares an ancestral place with me (Dorohoi), so maybe we’ll one day find that we’re related. The SIG leader, Barbara Hershey couldn’t make it … physically that is. She attended virtually on Daniel’s laptop.

Daniel Horowitz leading the ROM SIG meeting, with Barbara Hershey on his laptop

There were about 30 in attendance, which was the largest ROM-SIG meeting yet. We talked about records, projects, towns. Jay Sage volunteered to take on the job of ROM-SIG webmaster, but he’s also the new Vice President of the IAJGS, so he’ll be busy.

At 8 p.m. was yet another event that I was really looking forward to. The film “Aida’s Secrets”, sponsored by MyHeritage, was about two brothers separated at birth and given up for adoption. It was through genealogical research by Yad Vashem and MyHeritage that they found each other. What was of great interest to me was that one of the brothers, Shepsel Shell was well-known in my Jewish community of Winnipeg in Canada, went to my synagogue when I was growing up, and lived next door to my brother-in-law when he was growing up. Many scenes from the film were taken in Winnipeg.

Aida's SecretsShepsel Shell

Here’s an article from the Winnipeg Free Press from 2016 about this: “A secret revealed – Shepsel Shell’s family reunification subject of a new doc”

But it was the movie itself and the their mother’s “secrets” that were even more intriguing. Nothing is entirely clear. Following the movie, Daniel led an hour of boisterous discussion. Everyone had a different idea what might have happened.

In attendance to answer questions was Sima Velkovich from Yad Vashem in Israel who did all the Bergen-Belsen research. Also attending virtually (on the big screen after the movie) was British genealogist Laurence Harris whose research helped reunite the brothers.

Even though I had not seen the movie yet, my brother-in-law’s mother had, and she sent me to this conference with a number of questions to raise.

Neither Daniel nor the two experts could answer all the questions posed.

I’ll have lots to discuss with my brother-in-law and his mother when I see them this Friday.



I started Thursday morning on a fun note. I met Ron Arons for the first time a few days earlier and he and I just hit it off – we’re both the same type A people. When he showed up in that penguin costume on Sunday night, it just cracked me up. So I couldn’t pass up the opportunity to hear Ron speak at 8:15 on “Finding Living People on the Internet”.  I got there a few minutes late, and wanted to take a picture of him talking. He pointed me out and sternly scolded me and said, no photography. But in the end, he gave me full permission to post this picture of him speaking:

Ron Arons

p.s. You can’t hide, because Ron will find you.

Following Ron’s talk, I went to the Professional Genealogist’s get together. There were 27 of us there. Most were APG members. Jeanette Rosenberg from England led the discussion. I knew many of the attendees, but it was especially nice to meet and talk to Gary Mokotoff and Stanley Diamond in person.

I then had a few hours in the Resource Room. Stationed in the room was Sima Velkovich from Yad Vashem who was at the Aida’s Secret movie the night before. I had a nice conversation with Sima, and she even was able to provide me with some Bergen-Belsen documents relevant to the movie that I can take home and review. Maybe I’ll get some ideas to answer some of the unanswered questions.

I tried a few of the subscription databases that were available for free in the Resource Room that I hadn’t tried before. Didn’t come up with anything significant. A few of my queries led me to my own postings such as my Family Research web page.

Then I took a few hours off to do visit a few Disney sites. I took a Disney bus to Animal Kingdom so that I could transfer to Coronado Springs, a Disney resort I was at 18 years ago with my family. From there to a bus to Epcot, where I boarded the monorail and took a couple of loops. I got off at Magic Kingdom and would have taken a bus to Hollywood Studios (to make it 4 parks in 4 hours), but I had run out of time and just headed back to the Swan to make it back in time for the banquet.

Coronado Springs

There was a pre-banquest reception starting at 6:30 in the Swan Foyer. Then at 7:00 pm, Adam Brown opened the Gala banquet:

Adam Brown opening the Banquet

The featured speaker was Professor Henry Louis Gates, Jr., host of Finding Your Roots. He spoke prior to the meal, possibly for an hour. He talked on genealogy and genetics in America. What an eloquent, intelligent, entertaining speaker. It was a pleasure to listen to him. Apparently, it was the first time he ever spoke at a genealogy conference. And he said afterward that he really enjoyed the evening. His series airs again this fall on PBS starting October 3. Don’t miss it.

Professor Henry Louis Gates, Jr.



The conference still had a half-day of programming left. Personally, I hate the end of a conference. I find it so sad. So I like to leave a little early, and knowing that the banquet would be the highlight of the week, I set up my flight home for Friday morning.

But I had one last treat. Janet Akaha was on the same shuttle bus to the airport with me. It was nice to have a good conversations with her and for me to learn a little more about Y-DNA in the process.

That’s that. A very full, fun, and educational week. Next up is Halifax in October.

DMT Version 1.5.1 and IAJGS and DMT Workshop - Tue, 18 Jul 2017

I fixed a few bugs in Double Match Triangulator that I found while preparing for my workshop at the IAJGS Conference on Monday. I also changed DMT to display people ordered by longest segment rather than total segments, and released it as Version 1.5.1.

I’m looking forward to giving the workshop. We’re dealing with a lot of endogamy among these participants and there are still many advances to be made in the field of Triangulation with regards to developing methods to find common ancestors and map a person’s chromosome segments to those ancestors.


I expect to learn as much as the 25 or so participants of my workshop. Each will have slightly different sets of matches, different sets of people they’ve DNA tested, and interesting problems to overcome that I have not seen before. I look forward to hearing their questions, comments and suggestions and using this information to further develop Double Match Triangulator.

I gave all the participants a 4 page handout with some preparatory work they should do to download and assemble their own Chromosome Browser Results file along with a few CBR files for a few of their DNA relatives. This way the workshop will be more useful as they will will be analyzing their own data.

Over half the people will be bringing their own Windows laptops that have Excel 2007 or later on it. Currently DMT is a Windows program and uses Excel libraries to create the Excel output files that we will be analyzing. The others, some of whom will have Macs or iPads, are currently out of luck (unless they have a Windows emulator) and will have to used a workshop-supplied Windows computer or sit with their neighbour. I have plans to eliminate DMT’s dependency on Excel and to make a Mac version, but alas, not available yet.

It should also be very interesting to compare everyone’s DNA matches with everyone else. With endogamy, most participants will show up in other participant’s match lists and vice versa. Wouldn’t it be exciting if we had a few discoveries of genealogical cousins at the Workshop?

This will be my first IAJGS Conference. I look forward to it and to the opportunity to personally learn more about genealogical research in my ancestral towns from some of the experts who will be in attendance. The banquet on Thursday night will feature Professor Henry Louis Gates, Jr., host of the PBS program “Finding Your Roots” who will speak on “Genetics and Genealogy in America”.

Skip Gates 
Henry Louis Gates will highlight the week

And of course, I’ll get to see many of my genealogical friends again, and meet some others for the first time. Isn’t that always the best part of any Conference?