RLP 236: Strategies for Overcoming Endogamy

Nicole (1s):
This is Research Like A Pro. episode 236 Strategies for Overcoming Endogamy Welcome to Research Like a Pro a genealogy podcast about taking your research to the next level. Hosted by Nicole Dyer and Diana Elder accredited Genealogist professional Diana and Nicole are the mother daughter team@familylocket.com and the authors of research Like a Pro, a Genealogist Guide with Robin Wirthlin. They also co-authored the Companion Volume research like a Pro with DNA, Join, Diana, and Nicole as they discuss how to stay organized, make progress in their research and solve difficult cases. Let’s go.

Nicole (43s):
Hello everybody. Welcome to Research. Like a Pro

Diana (46s):
Hi, Nicole. How, are you today

Nicole (48s):
Doing well, How about you? What have you been doing?

Diana (51s):
I’ve been doing my morning reading in the National Genealogical Society quarterly and just finished an article this morning that I thought I would highlight because it was so unusual. It’s in the September, 2021 issue and it’s titled John Porter Langdon, one of four brothers to settle in California. It’s by Shirley Langdon Wilcox, who’s a certified Genealogist and I think the thing that was so interesting for me was the setting. I mean, have you read an article ever about settling Northern California in the 1850s?

Nicole (1m 27s):
I have read an article about California, but I don’t think it was in the 1850s. It was much later.

Diana (1m 33s):
Yeah, so this was really fun. It takes place in Humboldt County, which is fun because I had a cousin who lived there and we visited her years and years ago so I could kind of picture the area very mountainous and forested and beautiful. But the author Shirley, she had so many family letters and then a lot of county histories. Anyway, it was a really interesting case study and actually it’s pretty long. It was pretty fascinating and fun to read something just a little bit different than what I usually am studying, so that was fun. I always enjoy reading research in other areas.

Nicole (2m 9s):
That’s great. I actually have that issue of the ngs, so I’m just flipping through here and it’s kind of neat to see the transcriptions of some of these letters and the strike through when somebody had crossed off of Word and it’s just neat to see old letters being used

Diana (2m 24s):
And. it kind of gives you a hint of what it was really like for them because in one of the letters that talks about the husband going out to do some work and being attacked by a grizzly baron and being killed, and then another one of the family members was killed in a Native American conflict. And so just gives it a little bit of a picture of what it would’ve been like for our Ancestors, some of these remote locations as early pioneers.

Nicole (2m 51s):
Well, good job doing your reading this morning. Our announcements today are that we are starting our research Like a Pro Mini challenge for 2023, and today is actually the first day you can join us by going to our Facebook group. It’s the Research Like, a Pro Mini challenge group, and I’ll put the link in the show notes and we’ll work through a research problem with all seven of the research Like a Pro steps, and each day you’ll have a test to do and share what you found in the Facebook group. So we’d love for you to join us. We are also starting our research like Pro with DNA Study Group on February 1st. So if you’re interested in joining us, then just check to see if we have any spots open on the website and we’re mostly sold out of that, but there might be some opening up.

Nicole (3m 39s):
Also, we’re excited to be starting our research Like a Pro webinar series, a new offering for 2023 where we’ll have monthly case studies featuring the research Like a Pro process and sharing reports that we’ve done. Diana’s sharing the first one and then I’ll be doing the second one. Then we’ll have a case by Alice Childs and accredited Genealogist that we work with and we’ve got a couple other people who are gonna be presenting after that. So we’re just really looking forward to this and if you have a case you’ve worked on in a report that you’d like to share, please let us know. We’d love to have more of our research, Like a Pro alumni sharing their projects and our webinar series. Also a reminder that Roots Tech is open for registration.

Nicole (4m 20s):
We’re excited to see a lot of you in person there that’s coming up really quickly.

Diana (4m 24s):
Yeah, it is so exciting and I’m so excited for our webinar series. That’s going to be really fun. We’ve got a lot of people that have already registered for that and we’re looking forward to being able to talk about our research live and answer questions. So we invite you to join us this year in learning how we actually do this research that we’re always talking about. Well, we had a fun review of the podcast. She says, I love listening to your podcast. I have done lots of searching and finding things back several generations, but now I want to start at the beginning and work backwards with correct documentation. I know my parents, grandparents and great grandparents, I’ve heard we should write everything related to them, birth census, death occupations, et cetera, and write a report.

Diana (5m 6s):
What type of report do you write when you’re summarizing a person’s life? Do you have examples? What is the objective for this type of research? Find everything on the life of John Doe. Well, I thought this was such a fun review, comment question that I told this podcast listener that we would answer it on the podcast. So here are just a couple of thoughts. This would be an objective blush out the life of John Doe, or perhaps you would do several small reports leading up to writing this big biography. you know, maybe you’ve discovered that your ancestor serves in the military, but you really don’t know anything about that.

Diana (5m 48s):
And so you would want to do a project just on military service. So I’m just going to use my dad’s life as an example. and I know a lot about my dad. He told stories of his early life. He told about growing up in Oklahoma and all of his adventures, but he did not tell much about when he was in World War ii. And so I would like to flesh that out a little bit more in a history about him. you know, I have some real basics, but I’d like to research where he went to Naval Gunner School, I think is what it was called, and you know, see what his unit actually was involved in.

Diana (6m 30s):
He didn’t see any active duty because it was the very talent end of World War ii, but there’s so much more that I could learn and write about. So I would have that just be a project and then when I felt like I really had enough of these small projects, then I would put that together into a biography. No, I don’t have a good example of a report for that yet because that’s on my to-do list. I want to do that for each of my Ancestors, but I have lots of small reports and lots of things that I can bring together to do something like that. Nicole, any thoughts on that?

Nicole (7m 3s):
I love that answer. I think it’s such a great idea to focus on different aspects of your Ancestors life, different biographical details that you need to figure out and do. Small reports. It’s so easy to get overwhelmed when you have a big idea and you have to write a whole biography all at once. It’s so much easier to break it into pipe size pieces and it’s the best way to do your research too because it causes you to focus and more intensity on the answer to that one research question.

Diana (7m 29s):
Exactly. So I think that’s a great goal for all of us to do that for our mainline Ancestors. Well, let’s get to our topic for the day, which is talking about Endogamy. Let’s first of all talk about what Endogamy is, just a little bit of a definition and what we mean when we say that word Endogamy because this does come up quite a bit when we’re talking about dna.

Nicole (7m 54s):
All right. Well Endogamy is defined as the practice of marrying within the same ethnic, cultural, social, religious or tribal group. And that definition comes from the ISO wiki. And when marrying within the same group occurs over and over for several generations, descendants of that population begin to share many segments of D n A with each other. So in genetic Genealogy, when we say somebody has Endogamy in their tree, then we are meaning that it’s complicating their DNA analysis to find relatives and figure out the relationship with them through shared dna because they tend to share DNA with many people from their same ethnic group or social religious group.

Nicole (8m 37s):
And so it gets challenging and some groups of people have some of these challenges associated with Endogamy. But in my research I kind of found that not all of the people that have Endogamy like symptoms in their DNA analysis actually have the practice of marrying within within the same ethnic, cultural or social group. But the result that they see in their D N A analysis comes from the founder effect or the bottleneck effect, which are terms used in genetics that we’ll define later. So we’re gonna talk about all those things. Before we dive into that, just a reminder that Diana wrote about the three terms that often get confused when talking about Endogamy and DNA analysis.

Nicole (9m 19s):
She talked about Endogamy pedigree collapse and multiple relationships, and that was a great post that you did,

Diana (9m 26s):
Well Thank, you and I think that was really the first time that I clarified what every single one of those meant. So many times pedigree collapsed, multiple relationships get kind of put together in the same bucket, whereas they really are two very separate things. And so you know, that’s for anyone listening, if you didn’t read that blog post or listen to the podcast, that might be a good place to start to kind of separate in your mind what you might be seeing in your dna, whether it’s just multiple relationships, pedigree, collapse, score full on Endogamy. It’s good to have a grasp of what those all look like.

Nicole (10m 2s):
Yeah, sometimes a person will have one instance of a double cousin, which is a multiple relationships case, but that doesn’t mean that they have pedigree collapse or Endogamy. And so it’s good to be aware of the differences. Other people may have an isolated instance of pedigree collapse in their pedigree, just one of their grandparent sets were third cousins to each other or something like that. But those with Endogamy have multiple relationships with many of their DNA N matches and several instances of pedigree collapse over and over in their more recent tree. And then further the macin time even. So these multiple relationships and collapsed pedigrees cause an inflated amount of DNA n between a pair of DNA N matches who come from the same Endogamy community.

Nicole (10m 42s):
So they will be sharing more than the expected amount of DNA for the closest known relationship. And this is because of multiple pathways of inheritance from the same Ancestors and having multiple common ancestral couples.

Diana (10m 55s):
Right. And we’ve seen the, in some of our client projects where we have a Native American community that when we did the network graph or a cluster chart, it was just all one big mass because everyone was so interrelated. And another case we had was one set in Polynesia with the same thing, you know the island communities. So your DNA does look much different and you do have to work with it in a different way.

Nicole (11m 23s):
Right. You mentioned a couple different known Endogamy populations. Let’s talk about the differences between different Endogamy populations. Paul Woodbury talked about Endogamy as a spectrum in his Legacy family tree webinar, Dealing with Endogamy and he showed a continuum with non Endogamy populations on one end and then severe Endogamy on the other end with pedigree collapse and normal levels of Endogamy somewhere in between. So if you are wanting to learn more about Endogamy, I highly recommend that webinar Leah Larkin has also talked about this idea that Endogamy is a spectrum. She’s talked about mild, moderate and strong Endogamy and that was in her Roots Tech Talk from 2021 entitled When Your Tree Is a Banyan Untangling Endogamy.

Nicole (12m 10s):
And this recording isn’t online anymore, but Leah Larkin usually offers it annually through her own lecture series. So you can go to The DNA Geek dot com slash events to see when she might be offering it again. But she’s been collecting data about the average segment size for DNA matches where two or more of the grandparents of the test taker come from the same indogenous population. And she’s been compiling this information about the average segment size and sharing it in her lectures that she gives about Endogamy. What she has found is that the average segment size for matches in the Ancestry fourth cousin range, which is from 20 to 89 cent Morgans is much smaller for Endogamy populations than for non Endogamy populations.

Nicole (12m 55s):
So just this idea that a lot of small segments are adding up to be from 20 to 90 cent Morgans and sometimes can look like a lot of DNA and like, oh, this is a fourth cousin, we probably share, you know, third great grandparents. But then they’re actually a related way further back. They’re like seventh, eighth, ninth and 10th cousin several times over. And so you are not gonna find a common ancestor until you’ve built your tree back really far. So she has found that there’s evidence that you come from an monogamous population if you are able to calculate the average segment size for that third and fourth cousin range and see a big draw in the average segment size when you get to that fourth cousin range.

Nicole (13m 36s):
And she talks all about that in her lecture. and I actually watched one of her older lectures to refresh my memory of what she’s saying, that was available online from 2016 when she was first teaching about Endogamy at the I four G G conference, the Institute for Genetic Genealogy. But she said that that lecture is a little bit outdated now cuz she’s been accepting other people’s data about the total shared cent Morgans and the number of segments and then calculating the average segment size. And so then she’s been compiling that into a a table that you can see on her website. She has like a screenshot of her Roots Tech 2021 chart from her Banyan lecture.

Nicole (14m 16s):
So I’ll put a link to that in the show notes.

Diana (14m 18s):
I’m looking at that and I think it’s interesting the different groups. So she has South Carolina Free people of Color, Cajun, Colombian, Andes, Acadian, Ashkenazi Polynesian, yeah,

Nicole (14m 31s):
And old New Mexico,

Diana (14m 32s):
Old New Mexico. Okay. I was trying to think what was old nm,

Nicole (14m 37s):
Puerto Rican, Jamaican, Cuban, Eastern European French, Canadian Appalachian and Italian. And then she also puts in the no Endogamy group. And so the title of this slide in her blog post is Gauging Endogamy across Populations. And you can see that that the red cells, the ones that have red, those are ones where the average segment size is less than 10 cent Morgans. So you can see how that would be like this, you know, really small segments that are adding up to make it seem like the person is a fourth cousin but really they’re much more distant.

Diana (15m 7s):
So interesting and I think that it is valuable now that ancestry puts the largest segment on there, we can see how many segments and the largest segment, even though we don’t have any other segment data that can help us to gauge and see if this possibly could be a match through an Endogamy situation. you know, if you’re seeing a match that has 40 centor And, it looks good, but then you see that it’s made up of

Nicole (15m 34s):
Four segments

Diana (15m 36s):
Or even more. Yeah, it’s something crazy. Well so good just to be educated and learn about this when it pops up and you know, you may not have it in your DNA but it might occur in a DNA match and you would need to be aware or maybe a test taker that you’ve asked to help you with your dna. you know, we often don’t work just with our own dna, we’re working with a lot of different people’s dna and so it’s good to know about all these situations.

Nicole (16m 1s):
Right. And that’s why we’ve had to learn about it because we’ve had clients who’ve had Endogamy in their family or on one of their lines. And so when we’re doing the DNA analysis we notice, oh there’s tons of matches from this online. Oh look, it’s from French Canada or Acadia.

Diana (16m 16s):
Yeah. So let’s talk a little bit about why Endogamy occurs. You’ve, you’ve introduced that a little bit, but let’s dive a little bit more into that.

Nicole (16m 24s):
Well obviously Endogamy is definition is marrying within the same group over and over. So why does that happen though? Mild to moderate Endogamy often occurs in geographically isolated communities where there just aren’t very many marriage partners available and they’re all kind of descended from the same people who’ve always lived on the island. So like islands and mountainous areas, some examples of isolated communities with mild to moderate Endogamy include Appalachia, the Italian Alps and Puerto Rico. And those last two Paul Woodbury talked about in his Dealing with Endogamy lecture as places where he first learned about Endogamy. you know, he had a client project that was focused in Puerto Rico and so he was learning all about Endogamy and now he’s kind of become somebody who lectures about Endogamy and teaches about how to deal with it because he’s worked with it in his client projects.

Nicole (17m 14s):
Also he’s done research for small mountainous Italian population that had Endogamy just in that town. Moderate levels of Endogamy are also present in communities that encourage marriage within the same religion like Mennonites and the Amish. What was interesting when I was researching this is that I read the article on Wikipedia about Endogamy And, it Edman included our church as a community that encourages Endogamy the church of Jesus Christ of latter Day Saints are the Mormons. And that is true, however, I haven’t noticed the effects of Endogamy that Polynesians and Ashkenazi Jews more moderate or severe levels of Endogamy as far as the genetic Genealogy definition go.

Nicole (17m 57s):
But I think that’s because there have been so many people coming into Utah who are from different populations. There’s a lot of people joining the church over the time period from 1830 to the present that brought in new gene pools. you know, if I look at my tree, which is mostly members of our church, you know there are people from Denmark, England, colonial United States and different parts of the US all coming together. So the effects of Endogamy marrying within the same religion aren’t really seen for Mormons.

Diana (18m 29s):
Yeah, I would agree with that because we haven’t seen in our DNA any sign of that. you know, we had people coming in from all over in a continual stream of immigrants coming in.

Nicole (18m 40s):
Yeah. What I have seen is multiple relationships where like brothers Mary’s sisters and then their descendants are like double cousins. So I’ve seen that a little bit in you know, marriages within Utah in the early days. So that’s interesting. And then there obviously some polygamy which can Contribute the fundamentalist church, you know, an offshoot from our church in Colorado City. They have intermarried so much that they actually are having some negative effects of of that Endogamy with some of their children having rare diseases and things like that because they’re all descended from the same two founders basically.

Diana (19m 14s):
Yeah. So you know, another religion that we see this in is theology, Jewish religion because they have the mandated marriage to other Jews and severe population bottlenecks and you know, that is one of the typical populations everybody talks about with Endogamy, the Ashkenazi Jewish population. And so I think it’s so interesting to think of it of Endogamy in some of these other areas as well. Other religions.

Nicole (19m 43s):
Yeah. And what I was going to say is that just marrying within your religious community won’t cause severe levels of Endogamy like the Ashkenazi Jewish, they actually had additional factors that cause these genetic effects to where they’re all so related to each other and they had severe population bottlenecks like you said, where there’s just a small group of founders and I think I’ve seen numbers, you know, in the 800 level, I’ll have to check that but, and I don’t think they really know, they’re just kind of guessing. But there have been genetic studies about that. But the same thing happened with Polynesian. So they have experienced the founder effect in population bottlenecks over time as they populated more Polynesian islands.

Nicole (20m 31s):
And that has caused, you know, those at the more distant islands of Polynesia to have more severe Endogamy. A blog author that I follow, Kalani Manway, his blog is called Hawaiian d n a. And he talks a lot about kind of this effect of the founders settling the new islands and the population bottlenecks and how it’s created this severe level of Endogamy as seen in the genetic results of DNA testers. And the same thing with Ashkenazi Jews. They have the bottlenecks too. So I promised I would give the definition of those two terms. So here they are. This definition is from the National Human Genome Research Institute.

Nicole (21m 11s):
So the founder effect as related to genetics refers to the reduction in genomic variability that occurs when a small group of individuals becomes separated from a larger population. Over time the resulting new subpopulation will have genotypes and physical traits resembling the initial small separated group. And these may be very different from the original larger population.

Diana (21m 35s):
I love that. And I’m thinking that could apply to so many situations. you know, I’ve been thinking of Daniel Boone and when they went out to Kentucky it was such a small group of founders there and and the intermarriage there and we’ve had some people in our study group who descended from that group and found a very messy bit of D N A because of that. But you know, of course then that can get separated out. But if you have that same population just staying together like on an island, then that would really multiply, wouldn’t it?

Nicole (22m 8s):
Exactly. Okay. The next definition is the pop population bottleneck. And this is from Wikipedia. A population bottleneck or genetic bottleneck is a sharp reduction in the size of a population due to environmental events such as famines, earthquakes, floods, fires, disease and droughts or human activities such as speech aside, widespread violence or intentional calling and human population planning such events can reduce the variation in the gene pool of a population thereafter a smaller population with a smaller genetic diversity remains to pass on genes to future generations. And so I found in my research that the Ashkenazi Jewish community had two severe bottlenecks of population having to do with the crusades and just the general challenges that the Jewish community has experienced over the last couple thousand years.

Diana (22m 59s):
That’s so interesting. I had not really heard that term population bottleneck, but I love that definition. So this whole idea of population bottlenecks can cause many people from one ethnic group to share the same segments of D N A and these are called population segments, which is a term we hear a lot. And so a test taker with a grandparent from an Endogamy community may find tons of DNA matches sharing the same segment all from that same Endogamy community. And so this can actually be helpful in assigning that segment to a certain ethnicity. And Roberta Essis has written all about this on her blog DNA Explained and the title is What is a population bottleneck?

Diana (23m 41s):
Sometimes we think that if we share a segment with someone, we will find the most common ancestor without doubt. But what this is saying is that no we may not because it could all just be going to that Endogamy community and that same little segment is being passed around to everybody. Correct.

Nicole (24m 1s):
Right. And so a lot of the times we will dismiss those population segments and just ignore them as not being helpful. But they can be helpful, especially in assigning that segment to a specific ethnicity. Like if you know that you have a Polynesian grandparent and a bunch of Polynesian people are sharing a certain segment with you, you can probably say this is my Polynesian segment right here and if anyone shares with me on on that segment, then I kind of know which line it’s from.

Diana (24m 30s):
That is a great idea. And in Roberta’s new book, the DNA for Native American Genealogy, she does talk a lot about using segments to find ethnicity. you know the specifically is Native American, but I love that idea that if you figure out that that little segment is a certain population that can really help you to put your DNA matches in order trying to figure out how you are connected.

Nicole (24m 55s):
Yes. Well sometimes people from monogamous populations, they look at their family tree and they don’t see any instances of recent pedigree collapse. But as they build their pedigree back to more distant Ancestors like the fifth great grandparents and beyond, that’s when maybe they’ll start to find those instances of pedigree collapse. and I wrote about that on Lara Diamond’s blog who has Ashkenazi Jewish ancestry and she shared how she first discovered an instance of pedigree collapse in her tree. She found an ancestor with the same name in two different places in her tree. And then she noticed that the locations for that ancestor were geographically close and as she continued to study the locations, she realized that the location was actually in the same place.

Nicole (25m 40s):
So discovering that that ancestor was in her tree twice showed her that her second great-grandparents were her second cousins.

Diana (25m 45s):
That’s so interesting. It makes me wonder if as we continue building our tree back beyond some of those places where we’re stuck if we might find something similar. You don’t know what you don’t know on your family tree when you have those blank spots.

Nicole (25m 59s):
Exactly. I mean eventually all of our pedigrees collapse back to the same groups of founders of areas and things. And then back to the time in the medieval period when only a certain number of people survived. So Back to Laura Diamond, she had found, you know, multiple relationships with her cousin matches in the past she’d found, you know, several double cousins and things like that. And so it just highlights the fact that people from Endogamy populations both find both multiple relationships with DNA matches and pedigree collapse in their tree and their matches trees. So it’s a lot of things combining to cause the DNA matches to seem more closely related than they are.

Nicole (26m 40s):
And that’s one of the biggest challenges of DNA analysis with test from Endogamy communities that their matches from that same Endogamy community are more genetically similar to them than those from non Endogamy communities. and they will share more DNA N than the typical amounts according to the Shared Sun Morgan project and other studies. So this effect is mostly seen for matches that are more distant than first cousins. Your first cousins in an Incas community will probably share within the range for shared Santa Morgan project. But DNA matches that the testing companies put into the second cousin category are often more distant. They’ll be like a third, fourth and fifth cousin several times over

Diana (27m 18s):
And I think, as long as we understand that it’s going to help us so much in evaluating and trying to figure out how we connect with these DNA n A matches,

Nicole (27m 27s):
Right, it just becomes hard to prioritize D N A matches for further investigation because you’re not sure which matches are truly close matches. And then another challenge is that clustering doesn’t separate the matches into distant groups with the common ancestral line. Instead you’ll usually see one large single cluster with all the matches.

Diana (27m 46s):
Right. And we’ve seen that a lot.

Nicole (27m 48s):
Yeah, you can see a good example of this on Kalani’s website, Hawaiian d n a, he recently shared a blog post about shared matches in Clusterings from his own experience.

Diana (27m 59s):
That’s great. Well it is fun to talk about Endogamy. I know I first heard about it in the advanced DNA class at the Salt Lake Institute of Genealogy that I took from Karen Stanbury, I think it was her first advanced DNA class and Paul Woodbury was teaching and Paul has a great voice and so somebody in the class that asked about Endogamy and he burst out into song singing about Endogamy, it was So fun. That’s so hilarious. I love it. So if you ever listen to Paul talk, ask him to sing, he has great voice. But anyway, there was,

Nicole (28m 34s):
What song was it?

Diana (28m 35s):
He just said he sang Endogamy really funny. He used the words Endogamy and just sang that like three times with this like operatic voice. It was hilarious. Anyway, the questioner, the person who asked the question, she had this Ashkenazi Jewish case and was just trying to figure out how to deal with it. So I, I felt for her because way it is difficult.

Nicole (28m 58s):
Right. So a lot of the strategies you would normally use like clustering and evaluating with the Shared Center Morgan project are just not gonna work the same.

Diana (29m 6s):
No they are not.

Nicole (29m 8s):
Now I want to introduce a case that I worked on with part of our research team for a client who I will call Marie. She has given permission for her case to be discussed here and Marie has two grandparents from Endogamy communities. Her maternal grandfather was a French Canadian and her maternal grandmother was from Nova Scotia with Scottish and Acadian Origins. Her paternal side is free from Endogamy, they’re from Massachusetts. So to work with a Marie’s d n a I downloaded her ancestry, D n a matches to a spreadsheet using the D n a Jcom client and I just put a lower limit of 35 cent Morgans and she had 512 matches at ancestry sharing over 35 cent Morgans.

Nicole (29m 51s):
And then I went ahead and added a column to the spreadsheet to help me mark if the match was maternal or paternal. and I noticed she had far fewer paternal matches. So I actually just put an X for everyone who was paternal match. I just went down the match list at Ancestry and they have the maternal paternal designations. I knew which parent was which. So I changed it from parent one and parent two to maternal and paternal. Neither of her parents have tested but we figured it out through her first cousin matches and just her ethnicity of each side of the family and things. So what I found is that only 50 of the 512 matches were labeled as paternal and all the other 462 matches were maternal.

Nicole (30m 31s):
I expected that because her maternal side is where she has the French Canadian and Acadian lines, which are monogamous communities. French Canadians are often discussed as an monogamous group within the genetic Genealogy community. But through my research I think it might be more accurate to say that they experienced the founder effect and that caused them to have Endogamy like symptoms in their DNA test results.

Diana (30m 59s):
I really like that we have got that new terminology that you’ve introduced the founder effect because I think that helps better understand the history of some of these groups. The French Canadians descend from a small group of French immigrants who settled in Quebec from 1608 to 1760. And when the British took over New France in 1760 French immigration took Quebec. These French founders had children who probably married within their ethnic group also. They also intermarried with the Acadians and British settlers who began arriving increasing the genetic diversity of the population.

Nicole (31m 35s):
Right. So they didn’t strictly marry only within their ethnic group, they did do that, you know, married other French people who lived in Quebec. But the Acadians who had been in like what is now Prince Edward Island, a lot of them were deported to different parts of the world, including Quebec. And then you know, when the British took over, French immigration stopped and the British settlers started coming and there were also loyalists from New York who came during the Revolutionary war and all those people began intermarrying together in Quebec. And so you don’t see a severe Endogamy with French Canadians because they did marry into other groups. But because there was that small number of founders who came from 1608 to 1760 and then French immigration like dropped at that time.

Nicole (32m 22s):
Then there’s just kind of a few number of founders that all French Canadians seem to descend from. So they will often share a lot of D n A with other French Canadians and have a lot of distant matches.

Diana (32m 35s):
So did the American colonies also experience the founder effect?

Nicole (32m 39s):
You could could say that they do not to the same extent, but I found an article that was talking about Admixed ancestry and stratification of Quebec regional populations in the American Journal of Physical Anthropology and they kind of were comparing the numbers of the founders of the two groups that you mentioned. And so that article said that the British immigrants to the American colonies numbered about 360,000 and by contrast there were 8,500 founders of the French Canadian group. So that was thought to be a relatively small group. But I have heard people say that if you’re descended from the pilgrims then you’re going to match all the other people who are descended from the pilgrims because that’s also a small founder group. But because the pilgrim’s descendants did begin to intermarry with other people in the United States, I don’t think it’s as severe.

Diana (33m 25s):
Right. I remember in the DNA course I took last year with Blaine Beninger that on the class on Endogamy where he did mention that you know, that idea of American colonists, you know, having Endogamy in that group, it was so far back and it’s been so mixed up since then that you’re not gonna make a big difference to your dna. And also I was thinking about with the American colonies, they were spread out from Georgia all the way up to New England and you had many different groups coming over at different times and so they weren’t just isolated in a smaller area like you had in

Nicole (34m 2s):
Quebec. Yeah. and I think what also happened there in Quebec is the French speakers tended to associate with other French speakers and then you do see them inter marrying with the British. But now we have this French Canadian ethnicity where people identify as French Canadian because they descend from this group that did kind of stick together for a while.

Diana (34m 22s):
Right. Because culturally and linguistically they were the same.

Nicole (34m 26s):
Yeah, back to Marie. So she had this French Canadian maternal great-grandfather and then her maternal great-grandmother was from Nova Scotia and she had one parent that was Acadian and the other parent that was Scottish. And so the first people to live in that area, new France were French people and they became known as the Acadians then they were forcibly deported and some of them went down to Louisiana and became the Cajuns and some of them went to Quebec. Then that area was renamed different names. So like Prince Edward Island and Nova Scotia, a lot of Scottish people began immigrating there.

Nicole (35m 6s):
So on Marie’s line there, she has an Acadian who married a Scottish person. The Acadians had more severe Endogamy than the French Canadians from what I’ve learned.

Diana (35m 18s):
Well when you were working with Marie’s d n a, what were some of the strategies that she used?

Nicole (35m 23s):
Well, with Marie I decided to create a network graph to identify distinct clusters of matches from her family lines since only two of her grandparents were from an monogamous community and they weren’t from the same Endogamy community. So if, if all of your grandparents or most of your grandparents are from the same Endogamy community and network graph will probably not be helpful. But if not, then you could probably still do it. So for Marie’s network graph I used matches from 25 to 300 cent Morgans from ancestry d n a and there were 900,000 rows of shared matches in the in common with spreadsheet. And a common problem for making network graphs with test for monogamous populations is that the in common with file is too large to to edit in Excel, which has a limit of 1.04 million rows.

Nicole (36m 10s):
So if all of the matches are shared matches with each other, then there will be connecting lines between everyone in the graph. So limiting the range of Shareds Morgans can help, which is what I did. I only went down to 25 cent Morgans. But with severely Endogamy populations it, it doesn’t help even limiting the range of shareds. Morgans will still just be one big blob. So Marie’s network graph shows three large clusters accounting for almost all of her matches, 96% of the matches, the other 3.7% of the matches are divided into eight very tiny clusters, mostly representing Marie’s paternal side. So those clusters have like between 2, 3, 4 and like 16 matches in them. So her paternal side is very limited, but the maternal side has these like one enormous cluster and then a medium cluster and then like a medium large cluster, the medium cluster cluster zero, the orange one I found that those are descendants of Marie’s maternal grandmother’s Nova Scotia Ancestors who lived in the 18 hundreds.

Nicole (37m 8s):
So these are some of her closer matches possibly including her Scottish line. And then a lot of the connecting lines are going to this big huge green cluster that takes up most of the network graph that takes up 50% of the matches. And this cluster cluster number one, which is green, has a lot of connecting lines to the orange cluster. What I found when looking at the common ancestor hints is that these matches are descendants of Acadians living on what is now Prince Edward Island. And in 17 hundreds it was known as the is Saint John, how do you say that in French,

Diana (37m 40s):
Maybe

Nicole (37m 43s):
That was renamed Prince at Rhode Island. But that’s where a lot of Acadians lived. And so I’m thinking that’s the Acadian cluster And, it really shows there are just tons of distant matches in that group. Then the other medium large cluster, the pink one, cluster seven, I noticed that they share common Ancestors with Marie from Quebec. And so this appears to be the French Canadian cluster and many of the matches from the big green Acadian cluster and the pink French Canadian cluster have a lot of shared matches in common as illustrated by the thousands of connecting lines. Really joining those two clusters together, this probably means that they just all have multiple common Ancestors and probably some on different lines than Marie and just kind of the effect of the intermarriage between those two groups, the Acadians and the French Canadian, I’m not sure, but there definitely are a lot of relationships between those two groups.

Nicole (38m 36s):
So what’s interesting is that the Acadian line only counts for about one eighth of Marie’s pedigree, but that cluster accounts for 50% of the matches in her network graph. Wow.

Diana (38m 46s):
Yeah, and the image is really telling. So if you look at the blog post, any of you listening, you will see this huge green cluster that’s the Acadian group. It’s a really good visual of how much of how much DNA comes from that group.

Nicole (39m 3s):
Right. And the French Canadian cluster accounts for 34% of the matches. The high number of matches is sometimes a giveaway for Endogamy. So if you see that one particular group of your family has like dominates all the matches, then perhaps you’re seeing some of these effects of the founder effect population bottlenecks or true Endogamy of marrying within the same cluster of people. Well after learning about Leah Larkin strategy for finding the average segment size for different cousin groups like the second cousin range, the third cousin range, and the fourth cousin range, I decided to go ahead and figure out the average segment size for each of the clusters in my network.

Nicole (39m 44s):
Graphs and I kind of identified, you know, which ones were which. So in the Nova Scotia cluster from the 18 hundreds with Marie’s closer matches, this kind of had like a normal segment size of, you know, second cousins had 17 cent Morgan segment, average size, third cousins 17 as well, fourth cousins, 20 cent Morgans was the average size. So that cluster didn’t seem to have like the effects of Endogamy. And then the Acadian cluster with all those tons of distant matches, there were like two matches in the third cousin range from 90 to 199 cent Morgans. And the average segment size for them was 19 cent Morgans. But then if you go down to the fourth cousin range sharing between 20 and 89 cent Morgans of total shared dna, the average segment size for that group of Acadians was 11 cent Morgans.

Nicole (40m 34s):
So it jumps all the way down from 19 to 11. And so that is a hallmark of a more strongly monogamous community. And then with the French Canadians, the average segment size for fourth cousins was 21. So I didn’t see like a huge indication of a lot of small segments adding up there. So I think that could mean that there was maybe some but not a lot, you know. And then the paternal clusters, some of them had an average segment size of like 25 and 28, and then one of the paternal clusters must have been more distant and the average segment size was 16.

Diana (41m 10s):
Okay. So I’m just gonna clarify. If there’s an average of a smaller segment size, that means there’s a higher possibility of Endogamy because you are having a lot of small segments making up the total amount of DNA that you

Nicole (41m 23s):
Share, right? Exactly. And it’s just calculated by taking the total amount of shared DNA divided by the number of segments, which was very conveniently listed in the list of matches I downloaded from dna jed com, from Ancestry for Marie.

Diana (41m 39s):
Nice. All right. So we have talked a lot about Endogamy, what it looks like, what do we do if we have it, what are some strategies for working with it? When we’re doing our autosomal DNA analysis,

Nicole (41m 50s):
One of the strategies is to increase the threshold for the smallest segment. And it’s not really simple to do this, but Paul Woodbury talks about how you can do it, but it helps you to know which matches are truly second cousin level matches and those closer matches. Basically what you do is you manipulate a downloaded spreadsheet of matches showing you know the segments and you delete small segments to increase the threshold for the smallest segment. And so then you’ll recalculate the total amounts of shared D n a. So this can help you see which segment cousin matches are truly that close. So what I’ve kind of seen is that in severely Endogamy populations you may need to increase the threshold to 15 cent Morgans, but for more mild or moderate Endogamy populations, somewhere between 10 or 15 could be beneficial.

Nicole (42m 41s):
So I would recommend going to Paul Woodbury’s webinar and syllabus for that webinar, Dealing with Endogamy to get ideas on how to do that.

Diana (42m 49s):
Yeah, I love Paul’s Webinars because he always gives you practical things to do. you know, you get the high level explanation, then he tells you specifically what you can do.

Nicole (42m 57s):
Yeah. And another strategy you can do is to prioritize your match list and decide which matches to focus on by sorting by the longest segment instead of by the total amount of shared d n a. So you can do this in Family Tree dna n My Heritage and Jed Match 23 in 23andme doesn’t allow you to do that And, it only allows you to sort by strength and relationship and percentage of shared dna, but you can figure it out by using the advanced DNA N comparison, their chromosome browser tool ancestry doesn’t allow you to sort by longest segment either, but at least they do report the longest segment. And when I downloaded Marie’s match list recently using d n h com client, I did not see a column for the longest segment unfortunately. So that was disappointing.

Nicole (43m 38s):
But when I do keep track of my matches that I’m looking at in my Airtable research log, I do keep track of the longest segment. And so if you add several matches that you think are relevant to your Airtable base, then you could sort them by the longest segment field to help you prioritize further. One thing to remember though is that the longest segment isn’t the only thing to consider. You can look at both the total amount of shared d n A and the longest segment to help you prioritize the matches. So one thing I would do is in Airtable you can apply multiple levels of sorting just like in Excel. So you could first sort by the longest segment and then sort by the total shared D N A column or field.

Diana (44m 16s):
I have had people ask us if we should use the longest segment, do you know what the value is for putting the longest segment in Airtable? So this is such a good explanation that it can really help you if you are work worried about Endogamy. So I’m so glad you talked about that.

Nicole (44m 34s):
Yeah, you know, the real value of the longest segment is showing you another indication of how close the match is because you know, when you look at total shared dna, you’re thinking, oh, somebody who shares a hundred cent Morgans, they’re probably like a closer cousin. I should start there instead of with someone who shares 15 looking at the longest segment can do the same thing. If you see a segment that’s 50 cent Morgans, then you might think, oh, I can prioritize this person because another person who shares a total amount of 50 cent Morgans, but it’s five segments of 10 cent Morgans, you maybe wouldn’t prioritize that one as much, right? Because it’s just smaller segments from more distant Ancestors probably

Diana (45m 11s):
Such a good reason to look at that number and to keep track of that in your project. Well what about, we talked a little bit about this earlier ethnicity and the segments,

Nicole (45m 23s):
Right? So 23andme and Family Tree DNA provide these chromosome paintings with ethnicity segments painted on them. So this is another great way to use segment data to help you with your matches. One thing that really helps is if your test is from an end agamous community that has its own ethnicity label, then you can really use that tool to help you check and see if the ancestral line that you hypothesize for a segment matches the ethnicity for that segment that you can see on the painting. So if you have some mixing going on, like maybe you have some Ashkenazi Jewish segments and then some German segments or some British segments here and there, then it can really help you to identify which side of the family came from.

Nicole (46m 7s):
Because maybe you know like, oh, this is where my German ancestor is and this is where the Ashkenazi Jewish Ancestors. And so looking at those places on the ethnicity chromosome painting can help you identify where that segment belongs in your tree.

Diana (46m 20s):
Right? We can use DNA painter to map segments to Ancestors and that can be a helpful way to organize your DNA matches and figure out which segments come from which Ancestors and I love using DNA painter. And so Laura Diamond in her blog post chromosome mapping and Endogamy suggests that to be successful you should raise your threshold from seven centor to something higher around 10 to 15 centor for Endogamy populations. And then as you’ve said, viewing those segments with that an unknown match overlaps with can sometimes help you determine which lines are related through. So such a great way to use DNA painter and chromosome mapping to figure out those mystery matches.

Nicole (47m 5s):
Yeah, and you’ll have some matches who are related on like several different lines and you can really see that as you assign each segment to different ancestral couples. And it’s kinda like putting a puzzle together of like, okay, it looks like I have this ancestor in common with them and this segment overlaps with another person who just sends from the ancestor, but this other segment seems to be from a different ancestral couple and so you can kind of figure it out.

Diana (47m 30s):
Right? And one of the things that Roberta Estes recommends in her book on Native American DNA is if you are wanting to use some ethnicity painting and DNA painter, she recommends that you do a whole new chromosome map and just paint in all the segments, for instance, from the Native American population that you’ve got or your Polynesian group that you’ve got. And so you have just kind of a separate chromosome map that you can use and look at. So she has some really good ideas in that book also about using chromosome mapping to figure things out.

Nicole (48m 5s):
Right. And even if you don’t use the ethnicity chromosome paintings, you can just use the regular way of mapping your segments and DNA painter and assigning the ancestral couples and you can give them different certainty levels to help you remember that you are just kind of guessing on this one and putting things together a little by little.

Diana (48m 24s):
Yeah, I like how you can write notes, you can put as much in there as you want.

Nicole (48m 28s):
One strategy that we talk about a lot is increasing coverage. And this is really important for those for mengas communities, and this is the idea that just one test taker is just one data point and that’s not as helpful as several data points. So to help you determine truly relevant matches, not just super inflated distant matches, you can compare them with multiple test takers who descend from your research subject. There’s been several examples of people doing this in Endogamy communities. So you can go to Laura’s Genealogy for an example of that in her blog post called Endogamy and Action Sibling Edition. And she has several people that she’s tested and she compares how much they share with certain matches.

Nicole (49m 12s):
And so you can kind of get an idea of which matches to prioritize this way. Like if you see that one of your matches has a long segment with your brother and your dad, but with you it wasn’t very much you can kind of realize, oh, this match might be more important than I thought. Another thing with coverage is finding test takers who descend from the ancestral couple you are researching and people maybe have already tested who you can invite to share their matches with you. And one thing to really focus on when you’re doing this is any test takers whose Ancestors did not stay in the Endogamy community and those people, Paul Woodbury calls them genetic pioneers and they can help you find relevant matches to your research objective.

Nicole (49m 54s):
If they didn’t have like all these Acadian and French Canadian extra matches, they just have, you know, that one small line that goes back to French Canadian, then that could really help you to find matches that are relevant,

Diana (50m 7s):
Right? Genetic pioneers are important and you know, that can even be helpful in cases of pedigree collapse as well. you know, finding someone who moved away from the area. So that’s a great, great suggestion. Well what about X D A? Can that help us?

Nicole (50m 24s):
Absolutely. you know, the challenge with Endogamy populations is it’s hard to separate which matches came from which lines, but XD n a gives you a super clear pathway to which lines could have contributed in that segment of DNA N So this is a really helpful tool and so definitely find test takers who inherited X D N A from the ancestor you’re working on and focus on looking at long blocks of XD n a and trying to narrow down which ancestral lines and that XD n a could have come from. Just be careful with using small XD n a segments since there’s a higher chance of false matches on the X chromosome,

Diana (51m 2s):
Right? XD n a is really fun to use, but you do have to understand that inheritance. So you’ll wanna look at a good diagram of X D A mark on your pedigree chart. I like to print out or on my big pedigree chart on the wall, I have the XS all all marked so it can get confusing. So you wanna make sure you know exactly how that X D A works.

Nicole (51m 24s):
Yeah, I just always remember that it cannot pass through two generations of males in a row. Right? That’s the one thing I always just try to remember that.

Diana (51m 34s):
Yep. Alright, anything else that you wanna tell us about the conclusion to Marie’s case?

Nicole (51m 41s):
Well, with Marie’s case, we had a, a research question on her French Canadian line. The goal was to find the parents of her great-grandfather who was born in 1867 in Quebec and died in 19, in the 1930s in Massachusetts. And like a lot of French Canadians, they kind of migrated some of them down to the New England area. Previously our research had focused on one of Marie’s paternal lines that went back to Ireland and DNA evidence was somewhat scarce on that line. And so in that project we saw that a lot of her matches were maternal. So I was excited and hopeful that we would have a lot of DNA evidence to help move the French Canadian line further back in time.

Nicole (52m 22s):
However, when we dug into the matches, everybody was Acadian and Marie didn’t have any matches that were descended from the second great grandparents that we found using documentary research on that French Canadian line. So most of the research report was documentary evidence with some analysis of the clusters just showing which is which. But we didn’t find any French Canadian relevant matches that were helpful to the objective. But all the French Canadian matches were just further back in time sharing somewhat smaller segments and beyond where we had been able to trace Marie’s tree on that French Canadian line And. it was just complicated with all those Acadian matches.

Diana (53m 2s):
Yeah. Is that interesting? And she had so many matches, you would think that there would be some decent matches for the lines that you needed.

Nicole (53m 10s):
Right. So I, what I would do in the future to continue on that objective, would be to focus on a combination of documentary research and cluster analysis and the records. There are good enough in Quebec that I think we would be be able to extend the the lines back pretty easily with documentary research and parish records and things, then continue the cluster analysis since we were able to separate her matches into a cluster of French Canadian MA matches and a cluster of Acadian matches. We could work on identifying common Ancestors among those French Canadian matches in that cluster. And then I also noticed that two first cousins who descend from Marie’s maternal grandparents have tested an ancestry.

Nicole (53m 53s):
So asking them to share their d n a match list could help us prioritize which matches share a higher amount of D N A with longer segments. But both of those cousins also have Acadian ancestry. So it would be even better to target test one of Marie’s second cousins who descend from her great-grandparents on the French Canadian line than we would be able to weed out all of the Acadians.

Diana (54m 16s):
Yeah, it just points to the idea that this research has to be done in phases. You can’t do it all in one fell swoop. You gotta do a piece and then another piece and another piece, right? That’s how you make progress. It’s not like you have to throw up your hands and dismay and say, I cannot do any of this. You just tackle it and use some of these strategies and do one project at a time to get closer to your objectives. So thanks for writing this blog post and for researching Endogamy. We’ve learned so much as you mentioned at the beginning through our client projects that have come to us with these Endogamy populations that sometimes the client had no idea that they had.

Diana (54m 59s):
But when we dive into the dna, it certainly becomes apparent. you know, we hope everyone listening learns something about Endogamy. If you haven’t come across it in your own dna, perhaps you will in someone else’s that you’re working with or one of your matches.

Nicole (55m 14s):
All right, well have a great week everyone, and we’ll talk to you again next week.

Diana (55m 17s):
All right, bye-bye.

Nicole (55m 19s):
Bye. Thank you for listening. We hope that something you heard today will help you make progress in your research. If you want to learn more, purchase our books, research Like a Pro, and Research like a Pro with DNA on amazon.com and other book sellers. You can also register for our online courses or study groups of the same names. Learn more at family lock.com/services. To share your progress and ask questions, join our private Facebook group by sending us your book receipt or joining our courses to get updates in your email inbox each Monday. Subscribe to our newsletter@familylocket.com slash newsletter. Please Subscribe rate and review our podcast. We read each of you and are so thankful for them. We hope you’ll start now to research Like a Pro.