Identify Your Ancestors – Follow Nested Ancestral Segments

I don’t think that we actively think about our DNA segments as nested ancestors, like Russian Matryoshka dolls, but they are.

That’s exactly why segment information is critical for genealogists. Every segment, and every portion of a segment, has an incredibly important history. In fact, you could say that the further back in time we can track a segment, the more important it becomes.

Let’s see how to unveil nested segments. I’ll use my chromosome 20 as an example because it’s a smaller chromosome. But first, let’s start with my pedigree chart.

Pedigree

Click images to enlarge.

Before we talk about nested segments that originated with specific ancestors, it’s important to take a look at the closest portion of my maternal pedigree chart. My DNA segments came from and through these people. I’ll be working with the first 5 generations, beginning with my mother as generation #1.

Generation 1 – Parents

In the first generation, we receive a copy of each chromosome from each parent. I have a copy of chromosome 20 from my mother and a copy from my father.

At FamilyTreeDNA, you can see that I match my mother on the entire tested region of each chromosome.

Therefore, the entire length of each of my chromosomes is assigned to both mother and father because I received a copy from each parent. I’m fortunate that my mother’s DNA was able to be tested before she passed away.

We see that each copy of chromosome 20 is a total of 110.20 cM long with 17,695 SNPs.

Of course, my mother inherited the DNA on her chromosome 20 from multiple ancestors whose DNA combined in her parents, a portion of which was inherited by my mother. Mom received one chromosome from each of her parents.

I inherited only one copy of each chromosome (In this case, chromosome 20) from Mom, so the DNA of her two parents was divided and recombined so that I inherited a portion of my maternal chromosome 20 from both of my maternal grandparents.

Identifying Maternal and Paternal Matches

Associating matches with your maternal or paternal side is easy at FamilyTreeDNA because their Family Finder matching does it automatically for you if you upload (or create) a tree and link matches that you can identify to their proper place in your tree.

FamilyTreeDNA then uses that matching segment information from known, identified relatives in your tree to place people who match you both on at least one significant-sized segment in the correct maternal, paternal, (or both) buckets. That’s triangulation, and it happens automatically. All you have to do is click on the Maternal tab to view your triangulated maternal matches. As you can see, I have 1432 matches identified as maternal. 

Some other DNA testing companies and third-party tools provide segment information and various types of triangulation information, but they aren’t automated for your entire match list like Family Finder matching at FamilyTreeDNA.

You can read about triangulation in action at MyHeritage, here, 23andMe, here, GEDmatch, here, and DNAPainter, which we’ll use, here. Genetic Affairs AutoKinship tool incorporates triangulation, as does their AutoSegment Triangulation Cluster Tool at GEDmatch. I’ve compiled a reference resource for triangulation, here.

Every DNA testing vendor has people in their database that haven’t tested anyplace else. Your best strategy for finding nested segments and identifying matches to specific ancestors is to test at or transfer your DNA file to every vendor plus GEDmatch where people who test at Ancestry sometimes upload for matching. Ancestry does not provide segment information or a chromosome browser so you’ll sometimes find Ancestry testers have uploaded to GEDmatch, FamilyTreeDNA  or MyHeritage where segment information is readily available. I’ve created step-by-step download/upload instructions for all vendors, here.

Generation 2 – Grandparents

In the second generation, meaning that of my grandparents, I inherited portions of my maternal and paternal grandmother’s and grandfather’s chromosomes.

My maternal and paternal chromosomes can be divided into two pieces or groups each, one for each grandparent.

Using DNAPainter, we can see my father’s chromosome 20 on top and my mother’s on the bottom. I have previously identified segments assigned to specific ancestors which are represented by different colors on these chromosomes. You can read more about how to use DNAPainter, here.

We can divide the DNA inherited from each parent into the DNA inherited from each grandparent based on the trees of people we match. If we test cousins from each side, assigning segments maternally or paternally becomes much, much easier. That’s exactly why I’ve tested several.

For the rest of this article, I’m focusing only on my mother’s side because the concepts and methods are the same regardless of whether you’re working on your maternal side or your paternal side.

Using DNAPainter, I expanded my mother’s chromosome 20 in order to see all of the people I’ve painted on my mother’s side.

DNAPainter allows us to paint matching segments from multiple testing vendors and assign them to specific ancestors as we identify common ancestors with our matches.

Based on these matches, I’ve divided these maternal matches into two categories:

  • Maternal grandmother, meaning my mother’s mother, bracketed in red boxes
  • Maternal grandfather, meaning my mother’s father, bracketed in black boxes.

The text and arrows in these graphics refer to the colors of the brackets/boxes, and NOT the colors of the segments beside people’s names. For example, if you look at the large black box at far right, you’ll see several people, with their matching segments identified by multiple colored bars. The different colored segments (bars) mean I’ve associated the match with different ancestors in multiple or various levels of generations.

Generation 3 – Great-grandparents

Within those maternal and paternal grandparent segments, more nested information is available.

The black Ferverda grandfather segments are further divided into black, from Hiram Ferverda, and gold from his wife Eva Miller. The same concept applies to the red grandmother segments which are now divided into red representing Nora Kirsch and purple representing Curtis Lore, her husband.

While I have only been able to assign the first four segments (at the top) to one person/ancestor, there’s an entire group of matches who share the grouping of segments at right, in gold, descended through Eva Miller. The Miller line is Brethren and Mennonite with lots of testers, so this is a common pattern in my DNA matches.

Eva Miller, the gold ancestor, has two parents, Margaret Elizabeth Lentz and John David Miller, so her segments would come from those two sides.

Generation 4 and 5 – Fuschia Segment

I was able to track the segment shown in fuschia indicated by the blue arrow to Jacob Lentz and his wife Fredericka Ruhle, German immigrant ancestors. Other people in this same match (triangulation) group descend from Margaret Elizabeth Lentz and John David Miller – but that fuschia match is the one that shows us where that segment originated. This allows us to assign that entire gold/blue bracketed set of segments to a specific ancestor or ancestral couple because they triangulate, meaning they all match me and each other.

Therefore, all of the segments that match with the fuschia segment also track back to Jacob Lentz and Fredericka Ruhle, or to their ancestors. We would need people who descend from Jacob’s parents and/or Fredericka’s parents to determine the origins of that segment.

In other words, we know all of these people share a common source of that segment, even if we don’t yet know exactly who that common ancestor was or when they lived. That’s what the process of tracking back discovers.

To be very clear, I received that segment through Jacob and Fredericka, but some of those matches who I have not been able to associate with either Jacob or Fredericka may descend from either Jacob or Fredericka’s ancestors, not Jacob and Fredericka themselves. Connecting the dots between Jacob/Fredericka and their ancestors may be enlightening as to the even older source of that segment.

Let’s take a look at nested segments on my pedigree chart.

Nested Pedigree

Click to enlarge.

You can see the progression of nesting on my pedigree chart, using the same colors for the brackets/boxes. The black Ferverda box at the grandparent level encompasses the entire paternal side of my mother’s ancestry, and the red includes her mother’s entire side. This is identical to the DNAPainter graphic, just expressed on my pedigree chart instead of my chromosome 20.

Then the black gets broken into smaller nested segments of black, gold and fuschia, while the red gets broken into red and purple.

If I had more matches that could be assigned to ancestors, I would have even more nested levels. Of course, if I was using all of my chromosomes, not just 20, I would be able to go back further as well.

You can see that as we move further back in time, the bracketed areas assigned to each color become smaller and smaller, as do the actual segments as viewed on my DNAPainter chromosomes.

Segments Get Progressively Smaller

You can see in the pedigree chart and segment painting above that the segments we inherit from specific ancestors divide over time. As we move further and further back in our tree, the segments inherited from any specific ancestor get smaller and smaller too.

Dr. Paul Maier in the MyOrigins 3.0 White Paper provides this informative graphic that shows the reduction in segments and the number of ancestors whose DNA we carry reaching back in time.

I refer to this as a porcupine chart.

Eventually, we inherit no segments from red ancestors, and the pieces of DNA that we inherit from the distant blue ancestors become so small and fragmented that they cannot be positively identified as coming from a specific ancestor when compared to and matched with other people. That’s why vendors don’t show small segment matches, although different vendors utilize different segment thresholds.

The debate about how small is too small continues, but the answer is not simply segment size alone. There is no one-size-fits-all answer.

As segments become smaller, the probability, or chances that we match another person by chance (IBC) increases. Proof that someone shares a specific ancestor, especially when dealing with increasingly smaller segments is a function of multiple factors, such as tree completeness for both people, shared matches, parental match confirmation, and more. I wrote about What Constitutes Proof, here.

In the Family Finder Matching White Paper, Dr. Maier provides this chart reflecting IBD (Identical By Descent) and IBC (Identical By Chance) segments and the associated false positivity rate. That means how likely you are to match someone on a segment of that size by chance and NOT because you both share the DNA from a common ancestor.

I wrote Concepts: Identical by Descent, State, Population and Chance to help you better understand how this works.

In the chart below, I’ve combined the generations, relationships, # of ancestors, assuming no duplicates, birth year range based on an approximate 30-year generation, percent of DNA assuming exactly half of each ancestor’s DNA descends in each generation (which we know isn’t exactly accurate), and the average amount of total inherited cMs using that same assumption.

Note that beginning with the 7th generation, on average, we can expect to inherit less than 1% of the DNA of an ancestor, or approximately 55 total cM which may be inherited in multiple segments.

The amount of actual cMs inherited in each generation can vary widely and explains why, beginning with third cousins, some people won’t share DNA from a common ancestor above the various vendor matching thresholds. Yet, other cousins several generations removed will match. Inheritance is random.

Parallel Inheritance

In order to match someone else descended from that 11th generation ancestor, BOTH you AND your match will need to have inherited the exact SAME DNA segment, across 11 generations EACH in order to match. This means that 11 transmission events for each person will need to have taken place in parallel with that identical segment being passed from parent to child in each line. For 22 rolls of the genetic dice in a row, the same segment gets selected to be passed on.

You can see why we all need to work to prove that distant matches are valid.

The further back in time we work, the more factors we must take into consideration, and the more confirming proof is needed that a match with another individual is a result of a shared ancestor.

Having said that, shared distant matches ARE the key to breaking through brick-wall ancestors. We just need to be sure we are chasing the real deal and not a red herring.

Exciting Possibilities

The most exciting possibility is that some segments are actually passed intact for several generations, meaning those segments don’t divide into segments too small for matching.

For example, the 22 cM fuschia segment that tracks through generations 4 and 5 to Jacob Lentz and Fredericka Ruhle has been passed either intact or nearly intact to all of those people who stack up and match each other and me on that segment. 22 cM is definitely NOT a small segment and we know that it descended from either Jacob or Fredericka, or perhaps combined segments from each. In any case, if someone from the Lentz line in Germany tested and matched me on that segment (and by inference, the rest of these people too), we would know that segment descended to me from Jacob Lentz – or at least the part we match on if we don’t match on the entire segment.

This is exactly what nested segments are…breadcrumbs to ancestors.

Part of that 22cM segment could be descended from Jacob and part from Fredericka. Then of Jacob’s portion, for example, pieces could descend from both his mother and father.

This is why we track individual segments back in time to discern their origin.

The Promise of the Future

The promise of the future is when a group of other people triangulate on a reasonably sized segment AND know where it came from. When we match that triangulation group, their identified segment may well help break down our brick walls because we match all of them on that same segment.

It is exactly this technique that has helped me identify a Womack segment on my paternal line. I still haven’t identified our common ancestor, but I have confirmed that the Womacks and my Moore/Rice family interacted as neighbors 8 generations ago and likely settled together in Amelia county, migrating from eastern Virginia. In time, perhaps I’ll be able to identify the common Womack ancestor and the link into either my Moore or Rice lines.

I’m hoping for a similar breakthrough on my mother’s side for Philip Jacob Miller’s wife, Magdalena, 7 generations back in my tree. We know Magdalena was Brethren and where they lived when they took up housekeeping. We don’t know who her parents were. However, there are thousands of Miller descendants, so it’s possible that eventually, we will be able to break down that brick wall by using nested segments – ours and people who descend from Magdalena’s siblings, aunts, and uncles.

Whoever those people were, at least some of their descendants will likely match me and/or my cousins on at least one nested Miller segment that will be the same segment identified to their ancestors.

Genealogy is a team sport and solving puzzles using nested segments requires that someone out there is working on identifying triangulated segments that track to their common ancestors – which will be my ancestors too. I have my fingers crossed that someone is working on that triangulation group and I find them or they find me. Of course, I’m working to triangulate and identify my segments to specific ancestors – hoping for a meeting in the middle – that much-desired bridge to the past.

By the time you’ve run out of other records, nested segments are your last chance to identify those elusive ancestors. 

Do you have genealogical brick walls that nested segments could solve?

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Thank you so much.

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DNA for Native American Genealogy – Hot Off the Press!

Drum roll please…my new book, DNA for Native American Genealogy, was just released today, published by Genealogical.com.

I’m so excited! I expected publication around the holidays. What a pleasant surprise.

This 190-page book has been a labor of love, almost a year in the making. There’s a lot.

  • Vendor Tools – The book incorporates information about how to make the best use of the autosomal DNA tools offered by all 4 of the major testing vendors; FamilyTreeDNA, MyHeritage, Ancestry, and 23andMe.
  • Chromosome Painting – I’ve detailed how to use DNAPainter to identify which ancestor(s) your Native heritage descends from by painting your population/ethnicity segments provided by FamilyTreeDNA and 23andMe.
  • Y and Mitochondrial DNA – I’ve described how and when to utilize the important Y and mitochondrial DNA tests, for you and other family members.
  • Maps – Everyone wants to know about ancient DNA. I’ve included ancient DNA information complete with maps of ancient DNA sites by major Native haplogroups, gathered from many academic papers, as well as mapped contemporary DNA locations.
  • Haplogroups – Locations in the Americas, by haplogroup, where individual haplogroups and subgroups are found. Some haplogroups are regional in nature. If you happen to have one of these haplogroups, that’s a BIG HINT about where your ancestor lived.
  • Tribes – Want to know, by tribe, which haplogroups have been identified? Got you covered there too.
  • Checklist – I’ve provided a checklist type of roadmap for you to follow, along with an extensive glossary.
  • Questions – I’ve answered lots of frequently asked questions. For example – what about joining a tribe? I’ve explained how tribes work in the US and Canada, complete with links for relevant forms and further information.

But wait, there’s more…

New Revelations!!!

There is scientific evidence suggesting that two haplogroups not previously identified as Native are actually found in very low frequencies in the Native population. Not only do I describe these haplogroups, but I provide their locations on a map.

I hope other people will test and come forward with similar results in these same haplogroups to further solidify this finding.

It’s important to understand the criteria required for including these haplogroups as (potentially) Native. In general, they:

  • Must be found multiple times outside of a family group
  • Must be unexplained by any other scenario
  • Must be well-documented both genetically as well as using traditional genealogical records
  • Must be otherwise absent in the surrounding populations

This part of the research for the book was absolutely fascinating to me.

Description

Here’s the book description at Genealogical.com:

DNA for Native American Genealogy is the first book to offer detailed information and advice specifically aimed at family historians interested in fleshing out their Native American family tree through DNA testing.

Figuring out how to incorporate DNA testing into your Native American genealogy research can be difficult and daunting. What types of DNA tests are available, and which vendors offer them? What other tools are available? How is Native American DNA determined or recognized in your DNA? What information about your Native American ancestors can DNA testing uncover? This book addresses those questions and much more.

Included are step-by-step instructions, with illustrations, on how to use DNA testing at the four major DNA testing companies to further your genealogy and confirm or identify your Native American ancestors. Among the many other topics covered are the following:

    • Tribes in the United States and First Nations in Canada
    • Ethnicity
    • Chromosome painting
    • Population Genetics and how ethnicity is assigned
    • Genetic groups and communities
    • Y DNA paternal direct line male testing for you and your family members
    • Mitochondrial DNA maternal direct line testing for you and your family members
    • Autosomal DNA matching and ethnicity comparisons
    • Creating a DNA pedigree chart
    • Native American haplogroups, by region and tribe
    • Ancient and contemporary Native American DNA

Special features include numerous charts and maps; a roadmap and checklist giving you clear instructions on how to proceed; and a glossary to help you decipher the technical language associated with DNA testing.

Purchase the Book and Participate

I’ve included answers to questions that I’ve received repeatedly for many years about Native American heritage and DNA. Why Native DNA might show in your DNA, why it might not – along with alternate ways to seek that information.

You can order DNA for Native American Genealogy, here.

For customers in Canada and outside the US, you can use the Amazon link, here, to reduce the high shipping/customs costs.

I hope you’ll use the information in the book to determine the appropriate tests for your situation and fully utilize the tools available to genealogists today to either confirm those family rumors, put them to rest – or maybe discover a previously unknown Native ancestor.

Please feel free to share this article with anyone who might be interested.

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Disclosure

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

Thank you so much.

DNA Purchases and Free Uploads

Genealogy Products and Services

My Book

Genealogy Books

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DNA Beginnings: How Many DNA Matches Do I Have?

People often want to know how many DNA matches they have.

Sounds simple, right?

At some vendors, the answer to this question is easy to find, and at others, not so much.

How do you locate this information at each of the four major vendors?

What else do you need to know?

I’ve written handy step-by-step instructions for each company!

Matches at FamilyTreeDNA

Sign on at FamilyTreeDNA and under autosomal results, click on Family Finder Matches.

At the top of the next page, you’ll see your total number of matches along with matches that FamilyTreeDNA has been able to assign maternally or paternally based on creating/uploading a tree and linking known matches to that tree in their proper place.

Your parents do NOT need to have tested for the maternal/paternal bucketing functionality, but you DO need to identify some relatives and link their tests to their place in your tree. It’s that easy. Instructions for linking can be found in the “Linking Matches on Your Tree” section of this article (click here), along with information about how that helps you, or here.

Obviously, if your parents have tested, that’s the best scenario. For people who don’t have that option, FamilyTreeDNA is the ONLY vendor that offers this type of feature if your parents have NOT tested.

At FamilyTreeDNA, I have 7313 total matches of which 3169 are paternal, 1402 are maternal and 6 are related to both parents.

Hint – your siblings, their children, your children, grandchildren, etc. will be related to you on both your paternal and maternal sides.

If you don’t have an autosomal DNA test at FamilyTreeDNA, you can upload one from Ancestry, 23andMe, or MyHeritage for free. Click here for instructions.

Matches at MyHeritage

At MyHeritage, sign on and click on DNA, then DNA Matches.

At the top of your matches page, you’ll see your total number of matches.

At MyHeritage, I have 14,082 matches.

Matches are not broken down maternally and paternally automatically, but I can filter my matches in a wide variety of ways, including shared matches with either parent if they have tested, or other relatives.

If you don’t have an autosomal DNA test at MyHeritage, you can transfer one from Ancestry, 23andMe, or FamilyTreeDNA for free. Click here to begin your upload to MyHeritage.

Click here for instructions about how to download a copy of your DNA file from other vendors.

Matches at Ancestry

At Ancestry, sign on and click on DNA, then DNA Matches.

On your matches page, at the top, you’ll see a number of function widgets. Look for “Shared DNA.”

Click the down arrow to expand the Shared DNA box and you’ll see the total number of matches, along with the breakdown between 4th cousins or closer and distant matches.

Sometimes the number of matches doesn’t show up which means Ancestry’s servers are too busy to calculate the number of matches. Refresh your screen or try again in a few minutes. This happens often to me and always makes me question my sanity:)

I have 53,435 matches at Ancestry, of which 4,102 are estimated to be 4th cousins or closer and 49,333 are more distant.

For close matches only, if your parents have tested at Ancestry, when possible, Ancestry tells you on each match if that person is associated with your father’s side or your mother’s side.

You can’t upload DNA files from other vendors to Ancestry, but you can download a copy of your DNA file from Ancestry and upload to either FamilyTreeDNA or MyHeritage. Click here for instructions.

You can also download a copy of your tree from Ancestry and upload it to either of those vendors, along with your DNA file for best results.

Matches at 23andMe

23andMe functions differently from the other vendors. They set a hard limit on the number of matches you receive.

That maximum number differs based on the test version you took and if you pay for a membership subscription that provides enhanced medical information along with advanced filters and the ability to have a maximum of 5000 matches.

In order to purchase the membership subscription, you need to take their most current V5 test. If you tested with an earlier product, you will need to repurchase, retest or upgrade your current test which means you’ll need to spit in the vial again.

Please note the words, “up to 5000 relatives,” in the 23andMe verbiage. They also say that’s “over 3 times what you get” with their test without a subscription.

23andMe handles things differently from any other vendor in the industry. They made changes recently which created quite a stir because they removed some capabilities from existing customers and made those functions part of their subscription model. You can read about that here and here.

The match limit on the current 23andMe V5 test, WITHOUT the subscription, is 1500. If you tested previously on earlier kits, V2-V4, 23andMe has reinstated your prior maximum match limit which was 2000.

So, here’s the maximum match summary for 23andMe:

  • Earlier kits (V2-V4) – 2000 maximum matches
  • Current V5 kit with no subscription – 1500 maximum matches
  • Current V5 kit with subscription – 5000 maximum matches

Except, that’s NOT the number of matches you’ll actually see.

23andMe handles matching differently too.

23andMe matches you with their other customers up to your maximum, whatever that is, then subtracts the people who have not opted-in to genealogy matching. Remember, 23andMe focuses on health, not genealogy, so not all of their customers want matching.

Therefore, you’ll NEVER see your total number of allowed matches, which is why 23andMe cleverly says you “get access to up to 5000 relatives.”

Let’s look at my V4 test at 23andMe. Sign on and click on Ancestry, then DNA Relatives. (Please note, Ancestry is not Ancestry the company, but at 23andMe means genealogy results as opposed to medical/health results.)

At the top of your DNA Relatives page, you’ll see your total number of matches, before any sorting filters are applied.

23andMe does not automatically assign matches maternally or paternally, but if your parents have tested AND opt-in to matching, then you can filter by people who also match either parent.

I have 1796 matches at 23andMe, which means that 204 or 11% of my matches have not opted-in to matching.

You can’t upload DNA files from other vendors to 23andMe, but you can download a copy of your DNA file from 23andMe and upload to either FamilyTreeDNA or MyHeritage where you will assuredly receive more matches. Click here for instructions.

Summary

Each vendor has its own unique set of features and operates differently. It’s not so much the number of matches you have, but if you have the RIGHT match to break through a particular brick wall or provide you with a previously unknown photo of a cherished family member.

I encourage everyone to fish in all 4 of these ponds by testing or uploading your DNA. Uploading and matching are both free. Advanced tools require a small one-time unlock fee, but it’s significantly less than testing again. You can find step-by-step instructions to walk you through the process, here.

Have fun!!!

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Disclosure

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

Thank you so much.

DNA Purchases and Free Transfers

Genealogy Products and Services

Books

Genealogy Research

DNA Beginnings: What is a Match?

Before we evaluate matches at each of the four major vendors, FamilyTreeDNA, MyHeritage, Ancestry and 23andMe, let’s discuss what a DNA match is, what it means, and what it does NOT mean.

A Match to Another Person

Each of the four major vendors, but not some other vendors, provide matches to you and other individuals in their database.

This example from FamilyTreeDNA shows my mother’s match list listing me as her closest match, along with a kit I uploaded from Ancestry when I was recently updating upload/download article instructions for my readers. You don’t need to upload multiple kits to vendors.

Every vendor’s match list looks different, as is the information they provide. We will cover each vendor’s match list individually in future articles in this DNA Beginnings series.

Each vendor has different criteria for matching, but in essence, using that vendor’s match criteria – your DNA and the DNA of a person you match are identical on a section of DNA of a vendor-defined length.

Each of those vendors identifies the people who match each other and opt-in to matching in one way or another,

When you sign on to your account at each vendor, you’ll see a match list. Each of those people on that list match your DNA:

  • At or above the vendor-defined centiMorgan (cM) threshold. You can read more about centiMorgans here.
  • At or above the vendor-defined SNP threshold, meaning the number individual contiguous matching locations.

Each vendor has their own thresholds and internal algorithms that define matches. For example, a match of 8 cM with 1500 SNPs refers to both the length of the match (cM) and the density of locations within that segment of DNA that match between two people. Only matches above each vendor’s threshold appear on your match list.

Matches smaller than or beneath those vendor thresholds are considered less likely to be valid matches, so are excluded and do not appear on your match list.

Imputation Affects Matching

Different vendors test their customers’ DNA on different DNA chips:

  • Different chips test a different amount of DNA, but generally roughly 700,000 SNP locations
  • That 700K locations of DNA can be in different locations in your genome

In other words, just because two vendors both test 700,000 locations doesn’t mean they test the same 700,000 locations.

Even the same vendor will, over time, implement different DNA testing chips or modify the SNP locations tested on the same chip.

These different chips, chip versions and SNP locations are not fully compatible with each other, so the vendors use a technique known as imputation to level the playing field between non-identical files.

This is particularly relevant for vendors that accept uploads from other vendors.

In this example, we have 3 vendors and 10 different SNPs, or DNA locations.

  • Vendor 1, on their first Version 1 chip, tested locations 1-8.
  • Vendor 1, on their second V2 chip, tested locations 3-10.

Therefore only 6 locations, 3-8, were “common” between those two different chips used by the same vendor.

  • Vendor 2, on yet a different DNA testing chip version (V3) tested locations 1-4 and 7-10.
  • Vendor 3 on chip version V4 tested locations 2-5, 7, 8 and 10.

There are only 4 locations out of 10 tested by all the vendors’ chips.

If the vendor’s match criteria is that 10 locations in a row must match, then none of these people will match each other.

Sometimes differences occur because of chip differences, and sometimes a difference occurs because a location doesn’t read well for some reason.

In order to compensate for the differences in DNA locations tested/reported, a technique called imputation is widely used.

Imputation uses scientific probability techniques to fill in the blanks based on DNA that typically neighbors or “travels with” the nucleotides or DNA values, (T, A, C or G), found in the customer being tested.

Imputation allows all of those blanks to be filled in for all customers for each of those 10 locations, assuming the “missing DNA” is close to tested DNA locations.

It’s thanks to imputation that customers can download their raw DNA files from one vendor and upload to another for matching, even though the vendors don’t use the same exact chip.

Sometimes imputation is incorrect. Matching can be affected in both directions, meaning that some people will be on each other’s match lists who actually don’t match on a particular segment. Others would actually match if all of those locations were tested.

The highest quality matches are between people who tested at the same vendor, on the same chip or at two different vendors who use exactly the same chip. However, that’s often not possible and isn’t within the control of the customer.

False Positive Matches

This translates to, “You’re a match but not really” and is a headache for genealogists.

False positive matches show as a match between two people on their match lists, but they aren’t actually valid matches for genealogy.

  • A false positive match could occur as a result of imputation, of course.
  • A false positive match could also occur because the two people match because part of the DNA of their mother and part of the DNA of their father at those locations just happens to combine to appear as a match.

For purposes of these examples, presume that each of these matches exceeds the vendor’s match criteria so would be shown on your match list.

In our example, Person 1 and Person 2 match at all 10 locations, so they would appear on each other’s match lists.

However, if we could see the DNA of Person 2’s parents, we would see that Person 2 DOES match Person 1, but is NOT a valid match. Person 3 inherited the first 5 DNA locations from their mother and the second 5 DNA locations from their father.

While Person 2 technically is a match to Person 1, they aren’t a legitimate match because the segment of DNA that matches does not descend from the same parent. This means that the DNA did not descend in one piece from ONE ancestor, but clearly descended in pieces from two ancestors – one maternal and one paternal.

Therefore a technical match that is not a genealogical match because the DNA is inherited in part from both parents is known as a false positive and is said to be Identical by Chance, or IBC. You can read about IBC matches here.

False Negative Matches

A false negative match is just the opposite. False negatives occur when two people are NOT reported on each other’s match lists when they actually would match if all of the DNA at the various required locations were tested, read, and reported accurately. In other words, if imputation were not necessary.

  • False negatives can be caused by imputation not working as accurately as we would hope. Imputation is a probability tool, and it’s not perfect.
  • False negatives can also be caused by differing match thresholds at different vendors.

For example, if one vendor reports matches at 6 cM and above, and a second vendor reports matches at 8 cM and above, the same two people who match at 7 cM will match at the first vendor, but not at the second.

The only way you would ever know about a false negative match, because they aren’t reported, is if you simply happen to match at a vendor who allows smaller thresholds.

Also, keep in mind that each vendor creates their own imputations algorithms, so two different vendors using imputation on the same file may produce different results.

Determining Valid Matches

So, how might you determine which matches are actually valid matches?

That’s a great question.

There are useful “hints:”

  • If your parents have tested, a valid match will match one of your parents on that same segment of DNA. If your match does NOT match one of your parents, it’s a false positive match and invalid for genealogy.
  • If only one of your parents has tested, and your match does NOT match the tested parent, you can’t presume that person automatically matches your other, non-tested parent. That match could match your non-tested parent, or could be IBC.
  • If neither of your parents have tested, check to see if your match also matches close relatives who have tested, but not your descendants. For example, if a match also matches your aunt or uncle, or first cousins, that increases the probability that the match is probably valid.
  • The larger the match, the more likely it is to be a valid match. For example, matches in the 6-7 cM level are IBC about half the time. By the time you’re evaluating matches at the 20 cM level for a single segment, they are accurate almost all the time.

Keep in mind that each matching segment must be confirmed separately, and not every vendor shares the locations of the segments that match.

So What Is a Match?

  • A match is a person who is found on your match list at one of the major vendors.
  • A match at one vendor may not be on your match list if you both have DNA at another common vendor due to various reasons including the vendor’s match criteria, imputation, or file compatibility issues.
  • A match may be false positive, or IBC which means that person is not an accurate match for genealogy. This is especially true for smaller segment matches.
  • A false positive match can occur because of erroneous reads, imputation, or because your match is identical by chance.
  • The larger a matching segment of DNA, the more likely it is to be an accurate match meaning you and your match share a common ancestor.
  • The best way to tell if your match is valid is to compare your match to both of your parents as well.

A match is not a guarantee that you share a common ancestor unless you are matching to close relatives. You won’t match a close relative if the match is not valid.

What About You?

What is your plan to verify that your matches are valid?

Have your parents tested their DNA? Either of both parents?

If so, ask for your parents to upload their DNA with you to each vendor where you upload your own results.

At each vendor, you’ll have different matches. That’s exactly why we fish in multiple ponds.

I always work with my closest matches first, because I’m the most likely to be able to easily identify our common ancestor.

Locate your closest known relatives from both your mother’s side and your father’s side at each vendor. These people will be extremely helpful for our next article about shared matches.

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Disclosure

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

Thank you so much.

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What is a Heteroplasmy and Why Do I Care?

Most people have never heard of a heteroplasmy – but you might have one.

You Might Have a Heteroplasmy If…

…You have no exact matches at the full sequence mitochondrial DNA level.

A heteroplasmy is one of the first things I think of when someone tells me they have no exact full sequence matches but several that are a genetic distance of 1, meaning one mutation difference.

That phenomenon usually means the tester has a rare mutation that no one else has, at least no one who has tested their mitochondrial DNA (yet) – and that mutation just might be a heteroplasmy.

Heteroplasmies are generally (but not always) quite recent mutations. Actually, heteroplasmies are mutations caught in the act of mutating – kind of like an insect in genetic amber – frozen in time in your generation.

By Anders L. Damgaard – http://www.amber-inclusions.dk – Baltic-amber-beetle CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=16792582

Let’s say you might have a heteroplasmy. Or maybe you want to see if you do. Even if YOU don’t have a heteroplasmy, other people’s heteroplasmies can and will affect matching.

Here’s everything you ever wanted to know about heteroplasmies but didn’t know to ask😊

Heteroplasmies are Fascinating

A heteroplasmy is actually quite interesting because it’s a genetic mutation in progress.

This means you have two versions of a DNA sequence showing in your mitochondrial DNA at a specific location.

Said another way, at a specific genetic location, you show both of two separate nucleotides. Amounts detected of a second nucleotide greater than 20% are considered a heteroplasmy. Amounts below 20% are ignored. Generally, within a few generations, the mutation will resolve in one direction or the other – although some heteroplasmies persist for several generations and can sometimes define family branches.

If you’d like to read more about mitochondrial DNA, I wrote a series of step-by-step articles and combined them into one resource page, here.

Show Me!

You can easily check to see if you have a heteroplasmy by signing on to your FamilyTreeDNA account. Hopefully, you’ve taken the full sequence test.

Today, new testers, thankfully, can only purchase full sequence tests, so HVR1 results don’t present quite the same challenges when combined with heteroplasmies as they used to. We’ll talk about that in a minute.

If you have only taken the HVR1 or HVR1+HVR2 “Plus” test, as opposed to the Full Sequence, you can upgrade by signing on here and clicking on the “Full” button on the Maternal Ancestry section of your personal page.

These buttons will be pink if you’ve taken that test already, and grey if you need to upgrade. If you have an account at FamilyTreeDNA, you can add a mitochondrial DNA test to that same account by clicking on “Add Ons and Upgrades” at the top of your personal page. You can order a test if you’re a new customer, here.

How Do I Know if I Have a Heteroplasmy?

Your mitochondrial DNA has a total of 16,569 locations that you can think of as addresses. If your DNA at those locations is normal, meaning no mutations, they won’t be listed in your results.

Mutations are shown in your mitochondrial DNA results by a different letter at the end of the location.

For example, here are my mutations for my HVR1 region. Each of these locations in the HVR1 region has a mutation.

For locations that are shown in your results, meaning those where you have a mutation, you’ll see, in order:

  • A letter, either T, A, C or G
  • The location number
  • A different letter, typically another one of T, A, C or G, but sometimes a small d

For the first mutation, C16069T, the location address is 16069, the normal value is C, the mutation that occurred is T.

Heteroplasmies are shown in your mitochondrial DNA results by letters other than T, A, C, G or d at the end of the location.

I don’t have any heteroplasmies, so I’m switching to the results of a cousin who has a heteroplasmic mutation at location T16362Y to use as an example. The trailing Y means they have a heteroplasmy at location 16362.

But first, what do those letters mean?

The Letters

The letters stand for the nucleotide bases that comprise DNA, as follows:

  • T – Thymine
  • A – Adenine
  • C – Cytosine
  • G – Guanine
  • d – a deletion has occurred. There is no nucleotide at this location.

For location T16362Y, the first letter, T, is the “normal” value found at this location. If a mutation has occurred, the second letter is the mutated value. Normally, this is one of the other nucleotides, A, C or G.

Any other letter after the location has a specific meaning; in this case, Y means that both a C and a T were found, per the chart below.

Note – if you have a small letter t, a, c or g, it’s not a heteroplasmy, and I wrote about small letters and what they mean in the article, Mitochondrial DNA Part 2: What Do Those Numbers Mean?

Check Your Results

On your FamilyTreeDNA personal page in the mtDNA section, click on the Mutations tab.

If you’ve taken the full sequence test, you’ll see Extra Mutations. You’re looking for any mutation that ends in any letter other than T, A, C, G or d.

If you haven’t taken the full sequence test, you don’t have “Extra” mutations listed, but you can still view your mutations for the HVR1 and HVR2 regions.

Look for any value that has any letter other than T, A, C, G or lower case d at the end of the location.

The Y tells us that this location is a heteroplasmy.

Heteroplasmy Matching

Ok, let’s look at a heteroplasmy mutation at location 16326. A heteroplasmy can occur at any mitochondrial location. I’ve selected this location because it occurs in the HVR1 region of the mitochondrial DNA, so even people who haven’t tested at the full sequence level will see results for this location. Plus, the location at which the heteroplasmy occurs affects matching in different ways.

Using the example of T16362Y, the Y tells us that both nucleotides C and T were found. This location should match against anyone carrying the following values in the same location:

  • Y (letter indicating a C/T heteroplasmy)
  • T (standard or normal value)
  • C (mutated value)

However, currently at Family Tree DNA, the heteroplasmy only counts as a match to anyone with a Y, the specific heteroplasmy indicator, and the “normal” value of T, but not the mutated value of C.

This table shows how heteroplasmies are counted at FamilyTreeDNA. For heteroplasmy T16362Y, based on the value your potential match has at this location, you either will or will not be considered a match at that location.

Scenario Other Person’s Value Your Result – T16362Y
1 T16362Y – heteroplasmy indicator Match to you at this location
2 T16362T – normal value, not a mutation Match to you at this location
3 T16362C – mutated value Not counted as match to you at this location
  • If your match has a value of Y, the heteroplasmic C/T value, they are counted as a match to you, so no problem.
  • If your match has a value of T, the normal value, this location won’t be shown on their mutation list at all. They WILL be counted as a match to you so there’s no issue.
  • If your match has a value of C, the mutated value, in my opinion they should also be counted as a match to you, but they aren’t today. The logic, I believe, was that the most likely value is the standard or normal value and that the mutated value is much less likely to be accurate. Regardless, I’ve requested this change and am hoping for a matching adjustment in a future release for heteroplasmies.

Heteroplasmies do affect matching at the different levels.

Viewing Your Matches

Mitochondrial DNA, for testing purposes, is broken into three regions, HVR1 (hyper-variable region 1), HVR2 and the Coding Region.

At FamilyTreeDNA, you can view your matches at each level. The matches are cumulative, meaning that the HVR2 level includes the HVR1 level information, and the Coding Region level includes the HVR1 and HVR2 regions. That highest level which includes all three regions shows information from your entire your entire full mitochondrial DNA sequence.

Heteroplasmy Effects on Matching

If you otherwise match someone exactly, but one of you has a heteroplasmy and the other person carries the mutated value, you will be counted as a mismatch of 1 at the full sequence level.

A mismatch has different effects when it occurs in the HVR1, HVR2 or Coding Regions, respectively.

GD is an abbreviation for Genetic Distance which is how mutations are counted. A GD of 1 means the two people have one mutation difference between them.

In the following chart, the effects of you having a nonmatch, heteroplasmic or otherwise, in each of the regions is shown at each level. The region in which the mismatch occurs is shown in the first column, at left, and the effect the mismatch has on matching in each region is shown in columns 2-4.

The red sections are not counted as matches.

Mismatch Occurs in this Region HVR1 Level Match to Someone Else HVR2 Level Match to Someone Else Coding Region Level Match to Someone Else
HVR1 region nonmatch GD of 1 means no match GD of 1 means no match GD of 1 is a match
HVR2 region nonmatch Does not affect HVR1 – so you are a match GD of 1 means no match GD of 1 is a match
Coding Region nonmatch Does not affect HVR1 – so you are a match Does not affect HVR2 – so you are a match GD of 1 is a match

For purposes of this discussion, we’re assuming our two people being compared in the chart above match exactly on every other location so matching is not otherwise affected.

  • If your heteroplasmic nonmatch occurs in the HVR1 region – in other words, scenario 3 – you’ll fall into the HVR1 nonmatch row. That means you won’t be shown as a match at the HVR1 or HVR1+HVR2 levels, but you WILL be shown as a full sequence match.
  • If your heteroplasmic nonmatch is in the HVR2 region of addresses, it won’t affect your HVR1 matches, but it will affect your HVR2 and Coding Region matches. This means you will be shown as HVR1 match, not an HVR2 match, but will be a full sequence match.
  • If your heteroplasmic nonmatch is in the Coding Region, it won’t affect your HVR1 or HVR2 matches, but it will affect your Coding Region matches. However, it won’t preclude matches and you’ll be shown as a match in all three regions.

To be very clear, I have no issue with these match thresholds. It’s important to understand how this works, and therefore why heteroplasmic (and other) mismatches in specific regions affect our matches in the way they do.

Why Aren’t Mismatches of 1 Counted as Matches in the HVR1 or HVR2 Regions?

The match threshold at FamilyTreeDNA for the HVR1 and the HVR1+HVR2 regions, both small regions of about 1000 locations each, is that only an exact match is considered a match. Therefore, a heteroplasmic nonmatch in this region can really be confusing and sometimes misleading, especially if either or BOTH people have NOT tested at the full sequence level.

These are the match thresholds in effect today.

HVR1 GD or # of Mutations Allowed for a Match HVR2 GD or # of Mutations Allowed for a Match Coding Region GD or # of Mutations Allowed for a Match
0 – no mutations allowed 0 – no mutations allowed 3 mutations allowed

If both people match on either the heteroplasmy identified (Y in our case) or one person has the normal value – all is fine. But if one person has a heteroplasmy and the other has the mutated value – then a mismatch occurs. This is really only problematic when:

  • The heteroplasmy mismatch is in the HVR1 region and both people have only tested at that level, causing the two people to not match at all.
  • The heteroplasmy mismatch occurs in combination with other mutations that, cumulatively, push the two people over the GD 3 full sequence matching threshold.

The second scenario happens rarely, but I have seen situations where people don’t match their mothers, aunts, siblings, or other close relatives because of multiple heteroplasmic mutations occurring in different people.

And yes, this is hen’s teeth rare – but it does occasionally happen.

So, what’s the bottom line about heteroplasmies?

Heteroplasmy Bottom Line

  1. You can suspect a heteroplasmy if you have full sequence matches, but no exact matches.
  2. If you have a heteroplasmy in the HVR1 region, understand that you may not have many or any matches in the HVR1 and HVR2 regions. The remedy is to test at the full sequence level and check matches there.
  3. If you have a heteroplasmy and don’t match someone you expect to match – reach out to them and ask about their value at that specific location. If that location isn’t listed for them in their results, then they have no mutation there and your heteroplasmy is NOT the cause of you not matching with them.
  4. If you don’t match someone you expect to match, reach out to them and ask if THEY have any heteroplasmies. The easiest way to ask is, “Do you have any mutations listed that end with anything other than T, A, C, G or d?” Feel free to link to this article so that they’ll know where to look, and why you’re asking.

Do you have any heteroplasmies?

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Disclosure

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

Thank you so much.

DNA Purchases and Free Transfers

Genealogy Products and Services

Books

Genealogy Research

A Triangulation Checklist Born From the Question; “Why NOT Use Close Relatives for Triangulation?”

One of my readers asked why we don’t use close relatives for triangulation.

This is a great question because not using close relatives for triangulation seems counter-intuitive.

I used to ask my kids and eventually my students and customers if they wanted the quick short answer or the longer educational answer.

The short answer is “because close relatives are too close to reliably form the third leg of the triangle.” Since you share so much DNA with close relatives, someone matching you who is identical by chance can also match them for exactly the same reason.

If you trust me and you’re good with that answer, wonderful. But I hope you’ll keep reading because there’s so much to consider, not to mention a few gotchas. I’ll share my methodology, techniques, and workarounds.

We’ll also discuss absolutely wonderful ways to utilize close relatives in the genetic genealogical process – just not for triangulation.

At the end of this article, I’ve provided a working triangulation checklist for you to use when evaluating your matches.

Let’s go!

The Step-by-Step Educational Answer😊

Some people see “evidence” they believe conflicts with the concept that you should not use close relatives for triangulation. I understand that, because I’ve gone down that rathole too, so I’m providing the “educational answer” that explains exactly WHY you should not use close relatives for triangulation – and what you should do.

Of course, we need to answer the question, “Who actually are close relatives?”

I’ll explain the best ways to best utilize close relatives in genetic genealogy, and why some matches are deceptive.

You’ll need to understand the underpinnings of DNA inheritance and also of how the different vendors handle DNA matching behind the scenes.

The purpose of autosomal DNA triangulation is to confirm that a segment is passed down from a particular ancestor to you and a specific set of your matches.

Triangulation, of course, implies 3, so at least three people must all match each other on a reasonably sized portion of the same DNA segment for triangulation to occur.

Matching just one person only provides you with one path to that common ancestor. It’s possible that you match that person due to a different ancestor that you aren’t aware of, or due to chance recombination of DNA.

It’s possible that your or your match inherited part of that DNA from your maternal side and part from your paternal side, meaning that you are matching that other person’s DNA by chance.

I wrote about identical by descent (IBD), which is an accurate genealogically meaningful match, and identical by chance (IBC) which is a false match, in the article Concepts – Identical by…Descent, State, Population and Chance.

I really want you to understand why close relatives really shouldn’t be used for triangulation, and HOW close relative matches should be used, so we’re going to discuss all of the factors that affect and influence this topic – both the obvious and little-understood.

  • Legitimate Matches
  • Inheritance and Triangulation
  • Parental Cross-Matching
  • Parental Phasing
  • Automatic Phasing at FamilyTreeDNA
  • Parental Phasing Caveats
  • Pedigree Collapse
  • Endogamy
  • How Many Identical-by-Chance Matches Will I Have?
  • DNA Doesn’t Skip Generations (Seriously, It Doesn’t)
  • Your Parents Have DNA That You Don’t (And How to Use It)
  • No DNA Match Doesn’t Mean You’re Not Related
  • Imputation
  • Ancestry Issues and Workarounds
  • Testing Close Relatives is VERY Useful – Just Not for Triangulation
  • Triangulated Matches
  • Building Triangulation Evidence – Ingredients and a Recipe
  • Aunts/Uncles
  • Siblings
  • How False Positives Work and How to Avoid Them
  • Distant Cousins Are Best for Triangulation & Here’s Why
  • Where Are We? A Triangulation Checklist for You!
  • The Bottom Line

Don’t worry, these sections are logical and concise. I considered making this into multiple articles, but I really want it in one place for you. I’ve created lots of graphics with examples to help out.

Let’s start by dispelling a myth.

DNA Doesn’t Skip Generations!

Recently, someone emailed to let me know that they had “stopped listening to me” in a presentation when I said that if a match did not also match one of your parents, it was a false match. That person informed me that they had worked on their tree for three years at Ancestry and they have “proof” of DNA skipping generations.

Nope, sorry. That really doesn’t happen, but there are circumstances when a person who doesn’t understand either how DNA works, or how the vendor they are using presents DNA results could misunderstand or misinterpret the results.

You can watch my presentation, RootsTech session, DNA Triangulation: What, Why and How, for free here. I’m thrilled that this session is now being used in courses at two different universities.

DNA really doesn’t skip generations. You CANNOT inherit DNA that your parents didn’t have.

Full stop.

Your children cannot inherit DNA from you that you don’t carry. If you don’t have that DNA, your children and their descendants can’t have it either, at least not from you. They of course do inherit DNA from their other parent.

I think historically, the “skipping generations” commentary was connected to traits. For example, Susie has dimples (or whatever) and so did her maternal grandmother, but her mother did not, so Susie’s dimples were said to have “skipped a generation.” Of course, we don’t know anything about Susie’s other grandparents, if Susie’s parents share ancestors, recessive/dominant genes or even how many genetic locations are involved with the inheritance of “dimples,” but I digress.

DNA skipping generations is a fallacy.

You cannot legitimately match someone that your parent does not, at least not through that parent’s side of the tree.

But here’s the caveat. You can’t match someone one of your parents doesn’t with the rare exception of:

  • Relatively recent pedigree collapse that occurs when you have the same ancestors on both sides of your tree, meaning your parents are related, AND
  • The process of recombination just happened to split and recombine a segment of DNA in segments too small for your match to match your parents individually, but large enough when recombined to match you.

We’ll talk about that more in a minute.

However, the person working with Ancestry trees can’t make this determination because Ancestry doesn’t provide segment information. Ancestry also handles DNA differently than other vendors, which we’ll also discuss shortly.

We’ll review all of this, but let’s start at the beginning and explain how to determine if our matches are legitimate, or not.

Legitimate Matches

Legitimate matches occur when the DNA of your ancestor is passed from that ancestor to their descendants, and eventually to you and a match in an unbroken pathway.

Unbroken means that every ancestor between you and that ancestor carried and then passed on the segment of the ancestor’s DNA that you carry today. The same is true for your match who carries the same segment of DNA from your common ancestor.

False positive matches occur when the DNA of a male and female combine randomly to look like a legitimate match to someone else.

Thankfully, there are ways to tell the difference.

Inheritance and Triangulation

Remember, you inherit two copies of each of your chromosomes 1-22, one copy from your mother and one from your father. You inherit half of the DNA that each parent carries, but it’s mixed together in you so the labs can’t readily tell which nucleotide, A, C, T, or G you received from which parent. I’m showing your maternal and paternal DNA in the graphic below, stacked neatly together in a column – but in reality, it could be AC in one position and CA in the next.

For matching all that matters is the nucleotide that matches your match is present in one of those two locations. In this case, A for your mother’s side and C for your father’s side. If you’re interested, you can read more about that in the article, Hit a Genealogy Home Run Using Your Double-Sided Two-Faced Chromosomes While Avoiding Imposters.

You can see in this example that you inherited all As from your Mom and all Cs from your Dad.

  • A legitimate maternal match would match you on all As on this particular example segment.
  • A legitimate paternal match would match you on all Cs on this particular segment.
  • A false positive match will match you on some random combination of As and Cs that make it look like they match you legitimately, but they don’t.
  • A false positive match will NOT match either your mother or your father.

To be very clear, technically a false positive match DOES match your DNA – but they don’t match your DNA because you share a common ancestor with your match. They match you because random recombination on their side causes you to match each other by chance.

In other words, if part of your DNA came from your Mom’s side and part from your Dad’s but it randomly fell in the correct positional order, you’d still match someone whose DNA was from only their mother or father’s side. That’s exactly the situation shown above and below.

Looking at our example again, it’s evident that your identical by chance (IBC) match’s A locations (1, 3, 5, 7 & 9) will match your Mom. C locations (2, 4, 6 8, & 10) will match your Dad, but the nonmatching segments interleaved in-between that match alternating parents will prevent your match from matching either of your parents. In other words, out of 10 contiguous locations in our example, your IBC match has 5 As alternated with 5 Cs, so they won’t match either of your parents who have 10 As or 10 Cs in a row.

This recombination effect can work in either direction. Either or both matching people’s DNA could be randomly mixed causing them to match each other, but not their parents.

Regardless of whose DNA is zigzagging back and forth between maternal and paternal, the match is not genealogical and does not confirm a common ancestor.

This is exactly why triangulation works and is crucial.

If you legitimately match a third person, shown below, on your maternal side, they will match you, your first legitimate maternal match, and your Mom because they carry all As. But they WON’T match the person who is matching you because they are identical by chance, shown in grey below.

The only person your identical by chance match matches in this group is you because they match you because of the chance recombination of parental DNA.

That third person WILL also match all other legitimate maternal matches on this segment.

In the graphic above, we see that while the grey identical by chance person matches you because of the random combination of As from your mother and Cs from your father, your legitimate maternal matches won’t match your identical by chance match.

This is the first step in identifying false matches.

Parental Cross-Matching

Removing the identical by chance match, and adding in the parents of your legitimate maternal match, we see that your maternal match, above, matches you because you both have all As inherited from one parent, not from a combination of both parents.

We know that because we can see the DNA of both parents of both matches in this example.

The ideal situation occurs when two people match and they have both had their parents tested. We need to see if each person matches the other person’s parents.

We can see that you do NOT match your match’s father and your match does NOT match your father.

You do match your match’s mother and your match does match your mother. I refer to this as Parental Cross-matching.

Your legitimate maternal matches will also match each other and your mother if she is available for testing.

All the people in yellow match each other, while the two parents in gray do not match any of your matches. An entire group of legitimate maternal matches on this segment, no matter how many, will all match each other.

If another person matches you and the other yellow people, you’ll still need to see if you match their parents, because if not, that means they are matching you on all As because their two parents DNA combined just happened, by chance, to contribute an A in all of those positions.

In this last example, your new match, in green, matches you, your legitimate match and both of your mothers, BUT, none of the four yellow people match either of the new match’s parents. You can see that the new green match inherited their As from the DNA of their mother and father both, randomly zigzagging back and forth.

The four yellow matches phase parentally as we just proved with cross matching to parents. The new match at first glance appears to be a legitimate match because they match all of the yellow people – but they aren’t because the yellow people don’t match the green person’s parents.

To tell the difference between legitimate matches and identical by chance matches, you need two things, in order.

  • Parental matching known as parental phasing along with parental cross-matching, if possible, AND
  • Legitimate identical by descent (IBD) triangulated matches

If you have the ability to perform parental matching, called phasing, that’s the easiest first step in eliminating identical by chance matches. However, few match pairs will have parents for everyone. You can use triangulation without parental phasing if parents aren’t available.

Let’s talk about both, including when and how close relatives can and cannot be used.

Parental Phasing

The technique of confirming your match to be legitimate by your match also matching one of your parents is called parental phasing.

If we have the parents of both people in a match pair available for matching, we can easily tell if the match does NOT match either parent. That’s Parental Cross Matching. If either match does NOT match one of the other person’s parents, the match is identical by chance, also known as a false positive.

See how easy that was!

If you, for example, is the only person in your match pair to have parents available, then you can parentally phase the match on your side if your match matches your parents. However, because your match’s parents are unavailable, your match to them cannon tbe verified as legitimate on their side. So you are not phased to their parents.

If you only have one of your parents available for matching, and your match does not match that parent, you CANNOT presume that because your match does NOT match that parent, the match is a legitimate match for the other, missing, parent.

There are four possible match conditions:

  • Maternal match
  • Paternal match
  • Matches neither parent which means the match is identical by chance meaning a false positive
  • Matches both parents in the case of pedigree collapse or endogamy

If two matching people do match one parent of both matches (parental cross-matching), then the match is legitimate. In other words, if we match, I need to match one of your parents and you need to match one of mine.

It’s important to compare your matches’ DNA to generationally older direct family members such as parents or grandparents, if that’s possible. If your grandparents are available, it’s possible to phase your matches back another generation.

Automatic Phasing at FamilyTreeDNA

FamilyTreeDNA automatically phases your matches to your parents if you test that parent, create or upload a GEDCOM file, and link your test and theirs to your tree in the proper places.

FamilyTreeDNA‘s Family Matching assigns or “buckets” your matches maternally and paternally. Matches are assigned as maternal or paternal matches if one or both parents have tested.

Additionally, FamilyTreeDNA uses triangulated matches from other linked relatives within your tree even if your parents have not tested. If you don’t have your parents, the more people you identify and link to your tree in the proper place, the more people will be assigned to maternal and paternal buckets. FamilyTreeDNA is the only vendor that does this. I wrote about this process in the article, Triangulation in Action at Family Tree DNA.

Parental Phasing Caveats

There are very rare instances where parental phasing may be technically accurate, but not genealogically relevant. By this, I mean that a parent may actually match one of your matches due to endogamy or a population level match, even if it’s considered a false positive because it’s not relevant in a genealogical timeframe.

Conversely, a parent may not match when the segment is actually legitimate, but it’s quite rare and only when pedigree collapse has occurred in a very specific set of circumstances where both parents share a common ancestor.

Let’s take a look at that.

Pedigree Collapse

It’s not terribly uncommon in the not-too-distant past to find first cousins marrying each other, especially in rather closely-knit religious communities. I encounter this in Brethren, Mennonite and Amish families often where the community was small and out-marrying was frowned upon and highly discouraged. These families and sometimes entire church congregations migrated cross-country together for generations.

When pedigree collapse is present, meaning the mother and father share a common ancestor not far in the past, it is possible to inherit half of one segment from Mom and the other half from Dad where those halves originated with the same ancestral couple.

For example, let’s say the matching segment between you and your match is 12 cM in length, shown below. You inherited the blue segment from your Dad and the neighboring peach segment from Mom – shown just below the segment numbers. You received 6 cM from both parents.

Another person’s DNA does match you, shown in the bottom row, but they are not shown on the DNA match list of either of your parents. That’s because the DNA segments of the parents just happened to recombine in 6 cM pieces, respectively, which is below the 7 cM matching threshold of the vendor in this example.

If the person matched you at 12 cM where you inherited 8 cM from one parent and 4 from the other, that person would show on one parent’s match list, but not the other. They would not be on the parent’s match list who contributed only 4 cM simply because the DNA divided and recombined in that manner. They would match you on a longer segment than they match your parent at 8 cM which you might notice as “odd.”

Let’s look at another example.

click to enlarge image

If the matching segment is 20 cM, the person will match you and both of your parents on different pieces of the same segment, given that both segments are above 7 cM. In this case, your match who matches you at 20 cM will match each of your parents at 10 cM.

You would be able to tell that the end location of Dad’s segment is the same as the start location of Mom’s segment.

This is NOT common and is NOT the “go to” answer when you think someone “should” match your parent and does not. It may be worth considering in known pedigree collapse situations.

You can see why someone observing this phenomenon could “presume” that DNA skipped a generation because the person matches you on segments where they don’t match your parent. But DNA didn’t skip anything at all. This circumstance was caused by a combination of pedigree collapse, random division of DNA, then random recombination in the same location where that same DNA segment was divided earlier. Clearly, this sequence of events is not something that happens often.

If you’ve uploaded your DNA to GEDmatch, you can select the “Are your parents related?” function which scans your DNA file for runs of homozygosity (ROH) where your DNA is exactly the same in both parental locations for a significant distance. This suggests that because you inherited the exact same sequence from both parents, that your parents share an ancestor.

If your parents didn’t inherit the same segment of DNA from both parents, or the segment is too short, then they won’t show as “being related,” even if they do share a common ancestor.

Now, let’s look at the opposite situation. Parental phasing and ROH sometimes do occur when common ancestors are far back in time and the match is not genealogically relevant.

Endogamy

I often see non-genealogical matching occur when dealing with endogamy. Endogamy occurs when an entire population has been isolated genetically for a long time. In this circumstance, a substantial part of the population shares common DNA segments because there were few original population founders. Much of the present-day population carries that same DNA. Many people within that population would match on that segment. Think about the Jewish community and indigenous Americans.

Consider our original example, but this time where much of the endogamous population carries all As in these positions because one of the original founders carried that nucleotide sequence. Many people would match lots of other people regardless of whether they are a close relative or share a distant ancestor.

People with endogamous lines do share relatives, but that matching DNA segment originated in ancestors much further back in time. When dealing with endogamy, I use parental phasing as a first step, if possible, then focus on larger matches, generally 20 cM or greater. Smaller matches either aren’t relevant or you often can’t tell if/how they are.

At FamilyTreeDNA, people with endogamy will find many people bucketed on the “Both” tab meaning they triangulate with people linked on both sides of the tester’s tree.

An example of a Jewish person’s bucketed matches based on triangulation with relatives linked in their tree is shown above.

Your siblings, their children, and your children will be related on both your mother’s and father’s sides, but other people typically won’t be unless you have experienced either pedigree collapse where you are related both maternally and paternally through the same ancestors or you descend from an endogamous population.

How Many Identical-by-Chance Matches Will I Have?

If you have both parents available to test, and you’re not dealing with either pedigree collapse or endogamy, you’ll likely find that about 15-20% of your matches don’t match your parents on the same segment and are identical by chance.

With endogamy, you’ll have MANY more matches on your endogamous lines and you’ll have some irrelevant matches, often referred to as “false positive” matches even though they technically aren’t, even using parental phasing.

Your Parents Have DNA That You Don’t

Sometimes people are confused when reviewing their matches and their parent’s match to the same person, especially when they match someone and their parent matches them on a different or an additional segment.

If you match someone on a specific segment and your parents do not, that’s a false positive FOR THAT SEGMENT. Every segment has its own individual history and should be evaluated individually. You can match someone on two segments, one from each parent. Or three segments, one from each parent and one that’s identical by chance. Don’t assume.

Often, your match will match both you and your parent on the same segment – which is a legitimate parentally phased match.

But what if your match matches your parent on a different segment where they don’t match you? That’s a false positive match for you.

Keep in mind that it is possible for one of your matches to match your parent on a separate or an additional segment that IS legitimate. You simply didn’t inherit that particular segment from your parent.

That’s NOT the same situation as someone matching you that does NOT match one of your parents on the same segment – which is an identical by chance or false match.

Your parent having a match that does not match you is the reverse situation.

I have several situations where I match someone on one segment, and they match my parent on the same segment. Additionally, that person matches my parent on another segment that I did NOT inherit from that parent. That’s perfectly normal.

Remember, you only inherit half of your parent’s DNA, so you literally did NOT inherit the other half of their DNA. Your mother, for example, should have twice as many matches as you on her side because roughly half of her matches won’t match you.

That’s exactly why testing your parents and close family members is so critical. Their matches are as valid and relevant to your genealogy as your own. The same is true for other relatives, such as aunts and uncles with whom you share ALL of the same ancestors.

You need to work with your family member’s matches that you don’t share.

No DNA Match Doesn’t Mean You’re Not Related

Some people think that not matching someone on a DNA test is equivalent to saying they aren’t related. Not sharing DNA doesn’t mean you’re not related.

People are often disappointed when they don’t match someone they think they should and interpret that to mean that the testing company is telling them they “aren’t related.” They are upset and take issue with this characterization. But that’s not what it means.

Let’s analyze this a bit further.

First, not sharing DNA with a second cousin once removed (2C1R) or more distant does NOT mean you’re NOT related to that person. It simply means you don’t share any measurable DNA ABOVE THE VENDOR THRESHOLD.

All known second cousins match, but about 10% of third cousins don’t match, and so forth on up the line with each generation further back in time having fewer cousins that match each other.

If you have tested close relatives, check to see if that cousin matches your relatives.

Second, it’s possible to match through the “other” or unexpected parent. I certainly didn’t think this would be the case in my family, because my father is from Appalachia and my mother’s family is primarily from the Netherlands, Germany, Canada, and New England. But I was wrong.

All it took was one German son that settled in Appalachia, and voila, a match through my mother that I surely thought should have been through my father’s side. I have my mother’s DNA and sure enough, my match that I thought should be on my father’s side matches Mom on the same segment where they match me, along with several triangulated matches. Further research confirmed why.

I’ve also encountered situations where I legitimately match someone on both my mother’s and father’s side, on different segments.

Third, imputation can be important for people who don’t match and think they should. Imputation can also cause matching segment length to be overreported.

Ok, so what’s imputation and why do I care?

Imputation

Every DNA vendor today has to use some type of imputation.

Let me explain, in general, what imputation is and why vendors use it.

Over the years, DNA processing vendors who sell DNA chips to testing companies have changed their DNA chips pretty substantially. While genealogical autosomal tests test about 700,000 DNA locations, plus or minus, those locations have changed over time. Today, some of these chips only have 100,000 or so chip locations in common with chips either currently or previously utilized by other vendors.

The vendors who do NOT accept uploads, such as 23andMe or Ancestry, have to develop methods to make their newest customers on their DNA processing vendor’s latest chip compatible with their first customer who was tested on their oldest chip – and all iterations in-between.

Vendors who do accept transfers/uploads from other vendors have to equalize any number of vendors’ chips when their customers upload those files.

Imputation is the scientific way to achieve this cross-platform functionality and has been widely used in the industry since 2017.

Imputation, in essence, fills in the blanks between tested locations with the “most likely” DNA found in the human population based on what’s surrounding the blank location.

Think of the word C_T. There are a limited number of letters and words that are candidates for C_T. If you use the word in a sentence, your odds of accuracy increase dramatically. Think of a genetic string of nucleotides as a sentence.

Imputation can be incorrect and can cause both false positive and false negative matches.

For the most part, imputation does not affect close family matches as much as more distant matches. In other words, imputation is NOT going to cause close family members not to match.

Imputation may cause more distant family members not to match, or to have a false positive match when imputation is incorrect.

Imputation is actually MUCH less problematic than I initially expected.

The most likely effect of imputation is to cause a match to be just above or below the vendor threshold.

How can we minimize the effects of imputation?

  • Generally, the best result will be achieved if both people test at the same vendor where their DNA is processed on the same chip and less imputation is required.
  • Upload the results of both people to both MyHeritage and FamilyTreeDNA. If your match results are generally consistent at those vendors, imputation is not a factor.
  • GEDmatch does not use imputation but attempts to overcome files with low overlapping regions by allowing larger mismatch areas. I find their matches to be less accurate than at the various vendors.

Additionally, Ancestry has a few complicating factors.

Ancestry Issues

AncestryDNA is different in three ways.

  • Ancestry doesn’t provide segment information so it’s impossible to triangulate or identify the segment or chromosome where people match. There is no chromosome browser or triangulation tool.
  • Ancestry down-weights and removes some segments in areas where they feel that people are “too matchy.” You can read Ancestry’s white papers here and here.

These “personal pileup regions,” as they are known, can be important genealogically. In my case, these are my mother’s Acadian ancestors. Yes, this is an endogamous population and also suffers from pedigree collapse, but since this is only one of my mother’s great-grandparents, this match information is useful and should not be removed.

  • Ancestry doesn’t show matches in common if the shared segments are less than 20cM. Therefore, you may not see someone on a shared match list with a relative when they actually are a shared match.

If two people both match a third person on less than a 20 cM segment at Ancestry, the third person won’t appear on the other person’s shared match list. So, if I match John Doe on 19 cM of DNA, and I looked at the shared matches with my Dad, John Doe does NOT appear on the shared match list of me and my Dad – even though he is a match to both of us at 19 cM.

The only way to determine if John Doe is a shared match is to check my Dad’s and my match list individually, which means Dad and I will need to individually search for John Doe.

Caveat here – Ancestry’s search sometimes does not work correctly.

Might someone who doesn’t understand that the shared match list doesn’t show everyone who shares DNA with both people presume that the ancestral DNA of that ancestor “skipped a generation” because John Doe matches me with a known ancestor, and not Dad on our shared match list? I mean, wouldn’t you think that a shared match would be shown on a tab labeled “Shared Matches,” especially since there is no disclaimer?

Yes, people can be forgiven for believing that somehow DNA “skipped” a generation in this circumstance, especially if they are relatively inexperienced and they don’t understand Ancestry’s anomalies or know that they need to or how to search for matches individually.

Even if John Doe does match me and Dad both, we still need to confirm that it’s on the same segment AND it’s a legitimate match, not IBC. You can’t perform either of these functions at Ancestry, but you can elsewhere.

Ancestry WorkArounds

To obtain this functionality, people can upload their DNA files for free to both FamilyTreeDNA and MyHeritage, companies that do provide full shared DNA reporting (in common with) lists of ALL matches and do provide segment information with chromosome browsers. Furthermore, both provide triangulation in different ways.

Matching is free, but an inexpensive unlock is required at both vendors to access advanced tools such as Family Matching (bucketing) and triangulation at Family Tree DNA and phasing/triangulation at MyHeritage.

I wrote about Triangulation in Action at FamilyTreeDNA, here.

MyHeritage actually brackets triangulated segments for customers on their chromosome browser, including parents, so you get triangulation and parental phasing at the same time if you and your parent have both tested or uploaded your DNA file to MyHeritage. You can upload, for free, here.

In this example, my mother is matching to me in red on the entire length of chromosome 18, of course, and three other maternal cousins triangulate with me and mother inside the bracketed portion of chromosome 18. Please note that if any one of the people included in the chromosome browser comparison do not triangulate, no bracket is drawn around any others who do triangulate. It’s all or nothing. I remove people one by one to see if people triangulate – or build one by one with my mother included.

I wrote about Triangulation in Action at MyHeritage, here.

People can also upload to GEDmatch, a third-party site. While GEDmatch is less reliable for matching, you can adjust your search thresholds which you cannot do at other vendors. I don’t recommend routinely working below 7 cM. I occasionally use GEDmatch to see if a pedigree collapse segment has recombined below another vendor’s segment matching threshold.

Do NOT check the box to prevent hard breaks when selecting the One-to-One comparison. Checking that box allows GEDmatch to combine smaller matching segments into mega-segments for matching.

I wrote about Triangulation in Action at GEDmatch, here.

Transferring/Uploading Your DNA 

If you want to transfer your DNA to one of these vendors, you must download the DNA file from one vendor and upload it to another. That process does NOT remove your DNA file from the vendor where you tested, unless you select that option entirely separately.

I wrote full step-by-step transfer/upload instructions for each vendor, here.

Testing Close Relatives Is VERY Useful – Just Not for Triangulation

Of course, your best bet if you don’t have your parents available to test is to test as many of your grandparents, great-aunts/uncles, aunts, and uncles as possible. Test your siblings as well, because they will have inherited some of the same and some different segments of DNA from your parents – which means they carry different pieces of your ancestors’ DNA.

Just because close relatives don’t make good triangulation candidates doesn’t mean they aren’t valuable. Close relatives are golden because when they DO share a match with you, you know where to start looking for a common ancestor, even if your relative matches that person on a different segment than you do.

Close relatives are also important because they will share pieces of your common ancestor’s DNA that you don’t. Their matches can unlock the answers to your genealogy questions.

Ok, back to triangulation.

Triangulated Matches

A triangulated match is, of course, when three people all descended from a common ancestor and match each other on the same segment of DNA.

That means all three people’s DNA matches each other on that same segment, confirming that the match is not by chance, and that segment did descend from a common ancestor or ancestral couple.

But, is this always true? You’re going to hate this answer…

“It depends.”

You knew that was coming, didn’t you! 😊

It depends on the circumstances and relationships of the three people involved.

  • One of those three people can match the other two by chance, not by descent, especially if two of those people are close relatives to each other.
  • Identical by chance means that one of you didn’t inherit that DNA from one single parent. That zigzag phenomenon.
  • Furthermore, triangulated DNA is only valid as far back as the closest common ancestor of any two of the three people.

Let’s explore some examples.

Building Triangulation Evidence – Ingredients and a Recipe

The strongest case of triangulation is when:

  • You and at least two additional cousins match on the same segment AND
  • Descend through different children of the common ancestral couple

Let’s look at a valid triangulated match.

In this first example, the magenta segment of DNA is at least partially shared by four of the six cousins and triangulates to their common great-grandfather. Let’s say that these cousins then match with two other people descended from different children of their great-great-great-grandparents on this same segment. Then the entire triangulation group will have confirmed that segment’s origin and push the descent of that segment back another two generations.

These people all coalesce into one line with their common great-grandparents.

I’m only showing 3 generations in this triangulated match, but the concept is the same no matter how many generations you reach back in time. Although, over time, segments inherited from any specific ancestor become smaller and smaller until they are no longer passed to the next generation.

In this pedigree chart, we’re only tracking the magenta DNA which is passed generation to generation in descendants.

Eventually, of course, those segments become smaller and indistinguishable as they either aren’t passed on at all or drop below vendor matching thresholds.

This chart shows the average amount of DNA you would carry from each generational ancestor. You inherit half of each parent’s DNA, but back further than that, you don’t receive exactly half of any ancestor’s DNA in any generation. Larger segments are generally cut in two and passed on partially, but smaller segments are often either passed on whole or not at all.

On average, you’ll carry 7 cM of your eight-times-great-grandparents. In reality, you may carry more or you may not carry any – and you are unlikely to carry the same segment as any random other descendants but we know it happens and you’ll find them if enough (or the right) descendants test.

Putting this another way, if you divide all of your approximate 7000 cM of DNA into 7 cM segments of equal length – you’ll have 1000 7 cM segments. So will every other descendant of your eight-times-great-grandparent. You can see how small the chances are of you both inheriting that same exact 7 cM segment through ten inheritance/transmission events, each. Yet it does happen.

I have several triangulated matches with descendants of Charles Dodson and his wife, Anne through multiple of their 9 (or so) children, ten generations back in my tree. Those triangulated matches range from 7-38 cM. It’s possible that those three largest matches at 38 cM could be related through multiple ancestors because we all have holes in our trees – including Anne’s surname.

Click to enlarge image

It helps immensely that Charles Dodson had several children who were quite prolific as well.

Of course, the further back in time, the more “proof” is necessary to eliminate other unknown common ancestors. This is exactly why matching through different children is important for triangulation and ancestor confirmation.

The method we use to confirm the common ancestor is that all of the descendants who match the tester on the same segment all also match each other. This greatly reduces the chances that these people are matching by chance. The more people in the triangulation group, the stronger the evidence. Of course, parental phasing or cross-matching, where available is an added confirmation bonus.

In our magenta inheritance example, we saw that three of the males and one of the females from three different descendants of the great-grandparents all carry at least a portion of that magenta segment of great-grandpa’s DNA.

Now, let’s take a look at a different scenario.

Why can’t siblings or close relatives be used as two of the three people needed for triangulation?

Aunts and Uncles

We know that the best way to determine if a match is valid is by parental phasing – your match also matching to one of your parents.

If both parents aren’t available, looking for close family matches in common with your match is the next hint that genealogists seek.

Let’s say that you and your match both match your aunt or uncle in common or their children.

You and your aunts or uncles matching DNA only pushes your common ancestor back to your grandparents.

At that point, your match is in essence matching to a segment that belongs to your grandparents. Your matches’ DNA, or your grandparents’ DNA could have randomly recombined and you and your aunt/cousins could be matching that third person by chance.

Ok, then, what about siblings?

Siblings

The most recent common ancestor (MRCA) of you and someone who also matches your sibling is your parents. Therefore, you and your sibling actually only count as one “person” in this scenario. In essence, it’s the DNA of your parent(s) that is matching that third person, so it’s not true triangulation. It’s the same situation as above with aunts/uncles, except the common ancestor is closer than your grandparents.

The DNA of your parents could have recombined in both siblings to look like a match to your match’s family. Or vice versa. Remember Parental Cross-Matching.

If you and a sibling inherited EXACTLY the same segment of your Mom’s and Dad’s DNA, and you match someone by chance – that person will match your sibling by chance as well.

In this example, you can see that both siblings 1 and 2 inherited the exact same segments of DNA at the same locations from both of their parents.

Of course, they also inherited segments at different locations that we’re not looking at that won’t match exactly between siblings, unless they are identical twins. But in this case, the inherited segments of both siblings will match someone whose DNA randomly combined with green or magenta dots in these positions to match a cross-section of both parents.

How False Positives Work and How to Avoid Them

We saw in our first example, displayed again above, what a valid triangulated match looks like. Now let’s expand this view and take a look more specifically at how false positive matches occur.

On the left-hand (blue) side of this graphic, we see four siblings that descend through their father from Great-grandpa who contributed that large magenta segment of DNA. That segment becomes reduced in descendants in subsequent generations.

In downstream generations, we can see gold, white and green segments being added to the DNA inherited by the four children from their ancestor’s spouses. Dad’s DNA is shown on the left side of each child, and Mom’s on the right.

  • Blue Children 1 and 2 inherited the same segments of DNA from Mom and Dad. Magenta from Dad and green from Mom.
  • Blue Child 3 inherited two magenta segments from Dad in positions 1 and 2 and one gold segment from Dad in position 3. They inherited all white segments from Mom.
  • Blue Child 4 inherited all gold segments from Dad and all white segments from Mom.

The family on the blue left-hand side is NOT related to the pink family shown at right. That’s important to remember.

I’ve intentionally constructed this graphic so that you can see several identical by chance (IBC) matches.

Child 5, the first pink sibling carries a white segment in position 1 from Dad and gold segments in positions 2 and 3 from Dad. From Mom, they inherited a green segment in position 1, magenta in position 2 and green in position 3.

IBC Match 1 – Looking at the blue siblings, we see that based on the DNA inherited from Pink Child 5’s parents, Pink Child 5 matches Blue Child 4 with white, gold and gold in positions 1-3, even though they weren’t inherited from the same parent in Blue Child 4. I circled this match in blue.

IBC Match 2 – Pink Child 5 also matches Blue Children 1 and 2 (red circles) because Pink Child 5 has green, magenta, and green in positions 1-3 and so do Blue Children 1 and 2. However, Blue Children 1 and 2 inherited the green and magenta segments from Mom and Dad respectively, not just from one parent.

Pink Child 5 matches Blue Children 1, 2 and 4, but not because they match by descent, but because their DNA zigzags back and forth between the blue children’s DNA contributed by both parents.

Therefore, while Pink Child 5 matches three of the Blue Children, they do not match either parent of the Blue Children.

IBC Match 3 – Pink Child 6 matches Blue Child 3 with white, magenta and gold in positions 1-3 based on the same colors of dots in those same positions found in Blue Child 3 – but inherited both paternally and maternally.

You can see that if we had the four parents available to test, that none of the Pink Children would match either the Blue Children’s mother or father and none of the Blue Children would match either of the Pink Children’s mother or father.

This is why we can’t use either siblings or close family relatives for triangulation.

Distant Cousins Are Best for Triangulation & Here’s Why

When triangulating with 3 people, the most recent common ancestor (MRCA) intersection of the closest two people is the place at which triangulation turns into only two lines being compared and ceases being triangulation. Triangle means 3.

If siblings are 2 of the 3 matching people, then their parents are essentially being compared to the third person.

If you, your aunt/uncle, and a third person match, your grandparents are the place in your tree where three lines converge into two.

The same holds true if you’re matching against a sibling pair on your match’s side, or a match and their aunt/uncle, etc.

The further back in your tree you can push that MRCA intersection, the more your triangulated match provides confirming evidence of a common ancestor and that the match is valid and not caused by random recombination.

That’s exactly what the descendants of Charles Dodson have been able to do through triangulation with multiple descendants from several of his children.

It’s also worth mentioning at this point that the reason autosomal DNA testing uses hundreds/thousands of base pairs in a comparison window and not 3 or 6 dots like in my example is that the probability of longer segments of DNA simply randomly matching by chance is reduced with length and SNP density which is the number of SNP locations tested within that cM range.

Hence a 7 cM/500 SNP minimum is the combined rule of thumb. At that level, roughly half of your matches will be valid and half will be identical by chance unless you’re dealing with endogamy. Then, raise your threshold accordingly.

Ok, So Where are We? A Triangulation Checklist for You!

I know this has been a relatively long educational article, but it’s important to really understand that testing close relatives is VERY important, but also why we can’t effectively use them for triangulation.

Here’s a handy-dandy summary matching/triangulation checklist for you to use as you work through your matches.

  • You inherit half of each of your parents’ DNA. There is no other place for you to obtain or inherit your DNA. There is no DNA fairy sprinkling you with DNA from another source:)
  • DNA does NOT skip generations, although in occasional rare circumstances, it may appear that this happened. In this situation, it’s incumbent upon you, the genealogist, to PROVE that an exception has occurred if you really believe it has. Those circumstances might be pedigree collapse or perhaps imputation. You’ll need to compare matches at vendors who provide a chromosome browser, triangulation, and full shared match list information. Never assume that you are the exception without hard and fast proof. We all know about assume, right?
  • Your siblings inherit half of your parents’ DNA too, but not the same exact half of your parent’s DNA that you other siblings did (unless they are identical twins.) You may inherit the exact same DNA from either or both of your parents on certain segments.
  • Your matches may match your parents on different or an additional segment that you did not inherit.
  • Every segment has an individual history. Evaluate every matching segment separately. One matching segment with someone could be maternal, one paternal, and one identical by chance.
  • You can confirm matches as valid if your match matches one of your parents, and you match one of your match’s parents. Parental Phasing is when your match matches your parent. Parental Cross-Matching is when you both match one of each other’s parents. To be complete, both people who match each other need to match one of the parents of the other person. This rule still holds even if you have a known common ancestor. I can’t even begin to tell you how many times I’ve been fooled.
  • 15-20% (or more with endogamy) of your matches will be identical by chance because either your DNA or your match’s DNA aligns in such a way that while they match you, they don’t match either of your parents.
  • Your siblings, aunts, and uncles will often inherit the same DNA as you – which means that identical by chance matches will also match them. That’s why we don’t use close family members for triangulation. We do utilize close family members to generate common match hints. (Remember the 20 cM shared match caveat at Ancestry)
  • While your siblings, aunts, and uncles are too close to use for triangulation, they are wonderful to identify ancestral matches. Some of their matches will match you as well, and some will not because your close family members inherited segments of your ancestor’s DNA that you did not. Everyone should test their oldest family members.
  • Triangulate your close family member’s matches separately from your own to shed more light on your ancestors.
  • Endogamy may interfere with parental phasing, meaning you may match because you and/or your match may have inherited some of the same DNA segment(s) from both sides of your tree and/or more DNA than might otherwise be expected.
  • Pedigree collapse needs to be considered when using parental phasing, especially when the same ancestor appears on both sides of your family tree. You may share more DNA with a match than expected.
  • Conversely, with pedigree collapse, your match may not match your parents, or vice versa, if a segment happens to have recombined in you in a way that drops the matching segments of your parents beneath the vendor’s match threshold.
  • While you will match all of your second cousins, you will only match approximately 90% of your third cousins and proportionally fewer as your relationship reaches further back in time.
  • Not being a DNA match with someone does NOT mean you’re NOT related to them, unless of course, you’re a second cousin (2C) or closer. It simply means you don’t carry any common ancestral segments above vendor thresholds.
  • At 2C or closer, if you’re not a DNA match, other alternative situations need to be considered – including the transfer/upload of the wrong person’s DNA file.
  • Imputation, a scientific process required of vendors may interfere with matching, especially in more distant relatives who have tested on different platforms.
  • Imputation artifacts will be less obvious when people are more closely related, meaning closer relatives can be expected to match on more and larger segments and imputation errors make less difference.
  • Imputation will not cause close relatives, meaning 2C or closer, to not match each other.
  • In addition to not supporting segment matching information, Ancestry down-weights some segments, removes some matching DNA, and does not show shared matches below 20cM, causing some people to misinterpret their lack of common matches in various ways.
  • To resolve questions about matching issues at Ancestry, testers can transfer/upload their DNA files to MyHeritage, FamilyTreeDNA, and GEDmatch and look for consistent matches on the same segment. Start and end locations may vary to some extent between vendors, but the segment size should be basically in the same location and roughly the same size.
  • GEDmatch does not use imputation but allows larger non-matching segments to combine as a single segment which sometimes causes extremely “generous” matches. GEDmatch matching is less reliable than FamilyTreeDNA or MyHeritage, but you can adjust the matching thresholds.
  • The best situation for matching is for both people to test at the same vendor who supports and provides segment data and a chromosome browser such as 23andMe, FamilyTreeDNA, or MyHeritage.
  • Siblings cannot be used for triangulation because the most recent common ancestor (MRCA) between you and your siblings is your parents. Therefore, the “three” people in the triangulation group is reduced to two lines immediately.
  • Uncles and aunts should not be used for triangulation because the most recent common ancestors between you and your aunts and uncles are your grandparents.
  • Conversely, you should not consider triangulating with siblings and close family members of your matches as proof of an ancestral relationship.
  • A triangulation group of 3 people is only confirmation as far back as when two of those people’s lines converge and reach a common ancestor.
  • Identical by chance (IBC) matching occurs when DNA from the maternal and paternal sides are mixed positionally in the child to resemble a maternal/paternal side match with someone else.
  • Identical by chance DNA admixture (when compared to a match) could have occurred in your parents or grandparent’s generation, or earlier, so the further back in time that people in a triangulation group reach, the more reliable the triangulation group is likely to be.
  • The larger the segments and/or the triangulation group, the stronger the evidence for a specific confirmed common ancestor.
  • Early families with a very large number of descendants may have many matching and triangulated members, even 9 or 10 generations later.
  • While exactly 50% of each ancestor’s DNA is not passed in each generation, on average, you will carry 7 cM of your ancestors 10 generations back in your tree. However, you may carry more, or none.
  • The percentage of matching descendants decreases with each generation beyond great-grandparents.
  • The ideal situation for triangulation is a significant number of people, greater than three, who match on the same reasonably sized segment (7 cM/500 SNP or larger) and descend from the same ancestor (or ancestral couple) through different children whose spouses in descendant generations are not also related.
  • This means that tree completion is an important factor in match/triangulation reliability.
  • Triangulating through different children of the ancestral couple makes it significantly less likely that a different unknown common ancestor is contributing that segment of DNA – like an unknown wife in a descendant generation.

Whew!!!

The Bottom Line

Here’s the bottom line.

  1. Don’t use close relatives to triangulate.
  2. Use parents for Parental Phasing.
  3. Use Parental Cross-Matching when possible.
  4. Use close relatives to look for shared common matches that may lead to triangulation possibilities.
  5. Triangulate your close relatives’ DNA in addition to your own for bonus genealogical information. They will match people that you don’t.
  6. For the most reliable triangulation results, use the most distant relatives possible, descended through different children of the common ancestral couple.
  7. Keep this checklist of best practices, cautions, and caveats handy and check the list as necessary when evaluating the strength of any match or triangulation group. It serves as a good reminder for what to check if something seems “off” or unusual.

Feel free to share and pass this article (and checklist) on to your genealogy buddies and matches as you explain triangulation and collaborate on your genealogy.

Have fun!!!

_____________________________________________________________

Disclosure

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

Thank you so much.

DNA Purchases and Free Transfers

Genealogy Products and Services

Books

Genealogy Research

RootsTech Connect 2021: Comprehensive DNA Session List

I wondered exactly how many DNA sessions were at RootsTech this year and which ones are the most popular.

Unfortunately, we couldn’t easily view a list of all the sessions, so I made my own. I wanted to be sure to include every session, including Tips and Tricks and vendor sessions that might only be available in their booths. I sifted through every menu and group and just kept finding more and more buried DNA treasures in different places.

I’m sharing this treasure chest with you below. And by the way, this took an entire day, because I’ve listed the YouTube direct link AND how many views each session had amassed today.

Two things first.

RootsTech Sessions

As you know, RootsTech was shooting for TED talk format this year. Roughly 20-minute sessions. When everything was said and done, there were five categories of sessions:

  • Curated sessions are approximately 20-minute style presentations curated by RootsTech meaning that speakers had to submit. People whose sessions were accepted were encouraged to break longer sessions into a series of two or three 20-minute sessions.
  • Vendor booth videos could be loaded to their virtual boots without being curated by RootsTech, but curated videos by their employees could also be loaded in the vendor booths.
  • DNA Learning Center sessions were by invitation and provided by volunteers. They last generally between 10-20 minutes.
  • Tips and Tricks are also produced by volunteers and last from 1 to 15 minutes. They can be sponsored by a company and in some cases, smaller vendors and service providers utilized these to draw attention to their products and services.
  • 1-hour sessions tend to be advanced and not topics could be easily broken apart into a series.

Look at this amazing list of 129 DNA or DNA-related sessions that you can watch for free for the next year. Be sure to bookmark this article so you can refer back easily.

Please note that I started compiling this list for myself and I’ve shortened some of the session names. Then I realized that if I needed this, so do you.

Top 10 Most-Viewed Sessions

I didn’t know whether I should list these sessions by speaker name, or by the most views, so I’m doing a bit of both.

Drum roll please…

The top 10 most viewed sessions as of today are:

Speaker/Vendor Session Title Type Link Views
Libby Copeland How Home DNA Testing Has Redefined Family History Curated Session https://youtu.be/LsOEuvEcI4A 13,554
Nicole Dyer Organize Your DNA Matches in a Diagram Tips and Tricks https://youtu.be/UugdM8ATTVo 6175
Roberta Estes DNA Triangulation: What, Why, and How 1 hour https://youtu.be/nIb1zpNQspY 6106
Tim Janzen Tracing Ancestral Lines in the 1700s Using DNA Part 1 Curated Session https://youtu.be/bB7VJeCR6Bs 5866
Amy Williams Ancestor Reconstruction: Why, How, Tools Curated Session https://youtu.be/0D6lAIyY_Nk 5637
Drew Smith Before You Test Basics Part 1 Curated Session https://youtu.be/wKhMRLpefDI 5079
Nicole Dyer How to Interpret a DNA Cluster Chart Tips and Tricks https://youtu.be/FI4DaWGX8bQ 4982
Nicole Dyer How to Evaluate a ThruLines Hypothesis Tips and Tricks https://youtu.be/ao2K6wBip7w 4823
Kimberly Brown Why Don’t I Match my Match’s Matches DNA Learning Center https://youtu.be/A8k31nRzKpc 4593
Rhett Dabling, Diahan Southard Understanding DNA Ethnicity Results Curated Session https://youtu.be/oEt7iQBPfyM 4287

Libby Copeland must be absolutely thrilled. I noticed that her session was featured over the weekend in a highly prominent location on the RootsTech website.

Sessions by Speaker

The list below includes the English language sessions by speaker. I apologize for not being able to discern which non-English sessions are about DNA.

Don’t let a smaller number of views discourage you. I’ve watched a few of these already and they are great. I suspect that sessions by more widely-known speakers or ones whose sessions were listed in the prime-real estate areas have more views, but what you need might be waiting just for you in another session. You don’t have to pick and choose and they are all here for you in one place.

Speaker/Vendor Session Title Type Link Views
Alison Wilde SCREEN Method: A DNA Match Note System that Really Helps DNA Learning Center https://youtu.be/WaNnh_v1rwE 791
Amber Brown Genealogist-on-Demand: The Help You Need on a Budget You Can Afford Curated Session https://youtu.be/9KjlD6GxiYs 256
Ammon Knaupp Pattern of Genetic Inheritance DNA Learning Center https://youtu.be/Opr7-uUad3o 824
Amy Williams Ancestor Reconstruction: Why, How, Tools Curated Session https://youtu.be/0D6lAIyY_Nk 5637
Amy Williams Reconstructing Parent DNA and Analyzing Relatives at HAPI-DNA, Part 1 Curated Session https://youtu.be/MZ9L6uPkKbo 1021
Amy Williams Reconstructing Parent DNA and Analyzing Relatives at HAPI-DNA, Part 2 Curated Session https://youtu.be/jZBVVvJmnaU 536
Ancestry DNA Matches Curated Session https://youtu.be/uk8EKXLQYzs 743
Ancestry ThruLines Curated Session https://youtu.be/RAwimOgNgUE 1240
Ancestry Ancestry DNA Communities: Bringing New Discoveries to Your Family History Research Curated Session https://youtu.be/depeGW7QUzU 422
Andre Kearns Helping African Americans Trace Slaveholding Ancestors Using DNA Curated Session https://youtu.be/mlnSU5UM-nQ 2211
Barb Groth I Found You: Methods for Finding Hidden Family Members Curated Session https://youtu.be/J93hxOe_KC8 1285
Beth Taylor DNA and Genealogy Basics DNA Learning Center https://youtu.be/-LKgkIqFhL4 967
Beth Taylor What Do I Do With Cousin Matches? DNA Learning Center https://youtu.be/LyGT9B6Mh00 1349
Beth Taylor Using DNA to Find Unknown Relatives DNA Learning Center https://youtu.be/WGJ8IfuTETY 2166
David Ouimette I Am Adopted – How Do I Use DNA to Find My Parents? Curated Session https://youtu.be/-jpKgKMLg_M 365
Debbie Kennett Secrets and Surprises: Uncovering Family History Mysteries through DNA Curated Session https://youtu.be/nDnrIWKmIuA 2899
Debbie Kennett Genetic Genealogy Meets CSI Curated Session https://youtu.be/sc-Y-RtpEAw 589
Diahan Southard What is a Centimorgan Tips and Tricks https://youtu.be/uQcfhPU5QhI 2923
Diahan Southard Using the Shared cM Project DNA Learning Center https://youtu.be/b66zfgnzL0U 3172
Diahan Southard Understanding Ethnicity Results DNA Learning Center https://youtu.be/8nCMrf-yJq0 1587
Diahan Southard Problems with Shared Centimorgans DNA Learning Center https://youtu.be/k7j-1yWwGcY 2494
Diahan Southard 4 Next Steps for Your DNA Curated Session https://youtu.be/poRyCaTXvNg 3378
Diahan Southard Your DNA Questions Answered Curated Session https://youtu.be/uUlZh_VYt7k 3454
Diahan Southard You Can Do the DNA – We Can Help Tips and Tricks https://youtu.be/V5VwNzcVGNM 763
Diahan Southard What is a DNA Match? Tips and Tricks https://youtu.be/Yt_GeffWhC0 314
Diahan Southard Diahan’s Tips for DNA Matches Tips and Tricks https://youtu.be/WokgGVRjwvk 3348
Diahan Southard Diahan’s Tips for Y DNA Tips and Tricks https://youtu.be/QyH69tk-Yiw 620
Diahan Southard Diahan’s Tips about mtDNA testing Tips and Tricks https://youtu.be/6d-FNY1gcmw 2142
Diahan Southard Diahan’s Tips about Ethnicity Results Tips and Tricks https://youtu.be/nZFj3zCucXA 1597
Diahan Southard Diahan’s Tips about Which DNA Test to Take Tips and Tricks https://youtu.be/t–4R8H8q0U 2043
Diahan Southard Diahan’s Tips about When Your Matches Don’s Respond Tips and Tricks https://youtu.be/LgHtM3nS60o 3009
Diahan Southard Three Next Steps: Using Known Matches Tips and Tricks https://youtu.be/z1SVq8ME42A 118
Diahan Southard Three Next Steps: MRCA/DNA and the Paper Trail Tips and Tricks https://youtu.be/JB0cVyk-Y4Q 80
Diahan Southard Three Next Steps: Start With Known Matches Tips and Tricks https://youtu.be/BSNhaQCNtAo 68
Diahan Southard Three Next Steps: Additional Tools Tips and Tricks https://youtu.be/PqNPBLQSBGY 140
Diahan Southard Three Next Steps: Ancestry ThruLines Tips and Tricks https://youtu.be/KWayyAO8p_c 335
Diahan Southard Three Next Steps: MyHeritage Theory of Relativity Tips and Tricks https://youtu.be/Et2TVholbAE 80
Diahan Southard Three Next Steps: Who to Test Tips and Tricks https://youtu.be/GyWOO1XDh6M 111
Diahan Southard Three Next Steps: Genetics vs Genealogy Tips and Tricks https://youtu.be/Vf0DC5eW_vA 294
Diahan Southard Three Next Steps: Centimorgan Definition Tips and Tricks https://youtu.be/nQF935V08AQ 201
Diahan Southard Three Next Steps: Shared Matches Tips and Tricks https://youtu.be/AYcR_pB6xgA 233
Diahan Southard Three Next Steps: Case Study – Finding an MRCA Tips and Tricks https://youtu.be/YnlA9goeF7w 256
Diahan Southard Three Next Steps: Why Use DNA Tips and Tricks https://youtu.be/v-o4nhPn8ww 266
Diahan Southard Three Next Steps: Finding Known Matches Tips and Tricks https://youtu.be/n3N9CnAPr18 688
Diana Elder Using DNA Ethnicity Estimates in Your Research Tips and Tricks https://youtu.be/aJgUK3TJqtA 1659
Diane Elder Using DNA in a Client Research Project to Solve a Family Mystery 1 hour https://youtu.be/ysGYV6SXxR8 1261
Donna Rutherford DNA and the Settlers of Taranaki, New Zealand Curated Session https://youtu.be/HQxFwie4774 214
Drew Smith Before You Test Basics Part 1 Curated Session https://youtu.be/wKhMRLpefDI 5079
Drew Smith Before You Test Basics Part 2 Curated Session https://youtu.be/Dopx04UHDpo 2769
Drew Smith Before You Test Basics Part 3 Curated Session https://youtu.be/XRd2IdtA-Ng 2360
Elena Fowler Whakawhanaungatanga Using DNA – It’s Complicated (Māori heritage) Curated Session https://youtu.be/6XTPMzVnUd8 470
Elena Fowler Whakawhanaungatanga Using DNA – FamilyTreeDNA (Māori heritage) Curated Session https://youtu.be/fM85tt5ad3A 269
Elena Fowler Whakawhanaungatanga Using DNA – Ancestry (Māori heritage) Curated Session https://youtu.be/-byO6FOfaH0 191
Esmee Mortimer-Taylor Living DNA: Anathea Ring – Her Story Tips and Tricks https://youtu.be/MTE4UFKyLRs 189
Esmee Mortimer-Taylor Living DNA: Coretta Scott King Academy – DNA Results Reveal Tips and Tricks https://youtu.be/CK1EYcuhqmc 82
Fonte Felipe Ethnic Filters and DNA Matches: The Way Forward to Finding Your Lineage Curated Session https://youtu.be/mt2Rv2lpj7o 553
FTDNA – Janine Cloud Big Y: What is it? Why Do I Need It? Curated Session https://youtu.be/jiDcjWk4cVI 2013
FTDNA – Sherman McRae Using DNA to Find Ancestors Lost in Slavery Curated Session https://youtu.be/i3VKwpmttBI 738
Jerome Spears Elusive Distant African Cousins: Using DNA, They Can Be Found Curated Session https://youtu.be/fAr-Z78f_SM 335
Karen Stanbary Ruling Out Instead of Ruling In: DNA and the GPS in Action 1 hour https://youtu.be/-WLhIHlSyLE 548
Katherine Borges DNA and Lineage Societies Tips and Tricks https://youtu.be/TBYGyLHHAOI 451
Kimberly Brown Why Don’t I Match my Match’s Matches DNA Learning Center https://youtu.be/A8k31nRzKpc 4593
Kitty Munson Cooper Basics of Unknown Parentage Research Using DNA Part 1 Curated Session https://youtu.be/2f3c7fJ74Ig 2931
Kitty Munson Cooper Basics of Unknown Parentage Research Using DNA Part 2 Curated Session https://youtu.be/G7h-LJPCywA 1222
Lauren Vasylyev Finding Cousins through DNA Curated Session https://youtu.be/UN7WocQzq78 1979
Lauren Vasylyev, Camille Andrus Finding Ancestors Through DNA Curated Session https://youtu.be/4rbYrRICzrQ 3919
Leah Larkin Untangling Endogamy Part 1 Curated Session https://youtu.be/0jtVghokdbg 2291
Leah Larkin Untangling Endogamy Part 2 Curated Session https://youtu.be/-rXLIZ0Ol-A 1441
Liba Casson-Budell Shining a Light on Jewish Genealogy Curated Session https://youtu.be/pHyVz94024Y 162
Libby Copeland How Home DNA Testing Has Redefined Family History Curated Session https://youtu.be/LsOEuvEcI4A 13,554
Linda Farrell Jumpstart your South African research Curated Session https://youtu.be/So7y9_PBRKc 339
Living DNA How to do a Living DNA Swab Tips and Tricks https://youtu.be/QkbxhqCw7Mo 50
Lynn Broderick Ethical Considerations Using DNA Results Curated Session https://youtu.be/WMcRiDxPy2k 249
Mags Gaulden Importance and Benefits of Y DNA Testing DNA Learning Center https://youtu.be/MVIiv0H7imI 1032
Maurice Gleeson Using Y -DNA to Research Your Surname Curated Session https://youtu.be/Ir4NeFH_aJs 1140
Melanie McComb Georgetown Memory Project: Preserving the Stories of the GU272 Curated Session https://youtu.be/Fv0gHzTHwPk 320
Michael Kennedy What Can You Do with Your DNA Test? DNA Learning Center https://youtu.be/rKOjvkqYBAM 616
Michelle Leonard Understanding X-Chromosome DNA Matching Curated Session https://youtu.be/n784kt-Xnqg 775
MyHeritage How to Analyze DNA Matches on MH Curated Session https://youtu.be/gHRvyQYrNds 1192
MyHeritage DNA – an Overview Curated Session https://youtu.be/AIRGjEOg_xo 389
MyHeritage Advanced DNA Tools Curated Session https://youtu.be/xfZUAjI5G_I 762
MyHeritage How to Get Started with Your DNA Matches Tips and Tricks https://youtu.be/rU_dq1vt6z4 1901
MyHeritage How to Filter and Sort Your DNA Matches Tips and Tricks https://youtu.be/aJ7dRwMTt90 1008
Nicole Dyer How to Interpret a DNA Cluster Chart Tips and Tricks https://youtu.be/FI4DaWGX8bQ 4982
Nicole Dyer How to Evaluate a ThruLines Hypothesis Tips and Tricks https://youtu.be/ao2K6wBip7w 4823
Nicole Dyer Organize Your DNA Matches in a Diagram Tips and Tricks https://youtu.be/UugdM8ATTVo 6175
Nicole Dyer Research in the Southern States Curated Session https://youtu.be/Pouw_yPrVSg 871
Olivia Fordiani Understanding Basic Genetic Genealogy DNA Learning Center https://youtu.be/-kbGOFiwH2s 810
Pamela Bailey Information Wanted: Reuniting an American Family Separated by Slavery Tips and Tricks https://youtu.be/DPCJ4K8_PZw 105
Patricia Coleman Getting Started with DNA Painter DNA Learning Center https://youtu.be/Yh_Bzj6Atck 1775
Patricia Coleman Adding MyHeritage Data to DNA Painter DNA Learning Center https://youtu.be/rP9yoCGjkLc 458
Patricia Coleman Adding 23andMe Data to DNA Painter DNA Learning Center https://youtu.be/pJBAwe6s0z0 365
Penny Walters Mixing DNA with Paper Trail DNA Learning Center https://youtu.be/PP4SjdKuiLQ 2693
Penny Walters Collaborating with DNA Matches When You’re Adopted DNA Learning Center https://youtu.be/9ioeCS22HlQ 1222
Penny Walters Differences in Ethnicity Between My 6 Children DNA Learning Center https://youtu.be/RsrXLcXRNfs 400
Penny Walters Differences in DNA Results Between My 6 Children DNA Learning Center https://youtu.be/drnzW3FXScI 815
Penny Walters Ethical Dilemmas in DNA Testing DNA Learning Center https://youtu.be/PRPoc0nB4Cs 437
Penny Walters Adoption – Background Context Curated Session https://youtu.be/qC1_Ln8WCNg 1054
Penny Walters Adoption – Utilizing DNA Testing to Construct a Bio Family Tree Curated Session https://youtu.be/zwJ5QofaGTE 941
Penny Walters Adoption – Ethical Dilemmas and Varied Consequences of Looking for Bio Family Curated Session https://youtu.be/ZLcHHTSfCIE 576
Penny Walters I Want My Mummy: Ancient and Modern Egypt Curated Session https://youtu.be/_HRO50RtzFk 311
Rebecca Whitman Koford BCG: Brief Step-by-Step Tour of the BCG Website Tips and Tricks https://youtu.be/YpV9bKG6sXk 317
Renate Yarborough Sanders DNA Understanding the Basics DNA Learning Center https://youtu.be/bX_flUQkBEA 2713
Renate Yarborough Sanders To Test or Not to Test DNA Learning Center https://youtu.be/58-qzvN4InU 1048
Rhett Dabling Finding Ancestral Homelands Through DNA Curated Session https://youtu.be/k9zixg4uL1I 505
Rhett Dabling, Diahan Southard Understanding DNA Ethnicity Results Curated Session https://youtu.be/oEt7iQBPfyM 4287
Richard Price Finding Biological Family Tips and Tricks https://youtu.be/L9C-SGVRZLM 101
Robert Kehrer Will They Share My DNA (Consent, policies, etc.) DNA Learning Center https://youtu.be/SUo-jpTaR1M 480
Robert Kehrer What is a Centimorgan? DNA Learning Center https://youtu.be/dopniLw8Fho 1194
Roberta Estes DNA Triangulation: What, Why and How 1 hour https://youtu.be/nIb1zpNQspY 6106
Roberta Estes Mother’s Ancestors DNA Learning Center https://youtu.be/uUh6WrVjUdQ 3074
Robin Olsen Wirthlin How Can DNA Help Me Find My Ancestors? Curated Session https://youtu.be/ZINiyKsw0io 1331
Robin Olsen Wirthlin DNA Tools Bell Curve Tips and Tricks https://youtu.be/SYorGgzY8VQ 1207
Robin Olsen Wirthlin DNA Process Trees Guide You in Using DNA in Family History Research Tips and Tricks https://youtu.be/vMOQA3dAm4k 1708
Shannon Combs-Bennett DNA Basics Made Easy DNA Learning Center https://youtu.be/4JcLJ66b0l4 1560
Shannon Combs-Bennett DNA Brick Walls DNA Learning Center https://youtu.be/vtFkT_PSHV0 450
Shannon Combs-Bennett Basics of Genetic Genealogy Part 1 Curated Session https://youtu.be/xEMbirtlBZo 2263
Shannon Combs-Bennett Basics of Genetic Genealogy Part 2 Curated Session https://youtu.be/zWMPja1haHg 1424
Steven Micheleti, Joanna Mountain Genetic Consequences of the Transatlantic Slave Trade Part 1 Curated Session https://youtu.be/xP90WuJpD9Q 2284
Steven Micheleti, Joanna Mountain Genetic Consequences of the Transatlantic Slave Trade Part 2 Curated Session https://youtu.be/McMNDs5sDaY 742
Thom Reed How Can Connecting with Ancestors Complete Us? Curated Session https://youtu.be/gCxr6W-tkoY 392
Tim Janzen Tracing Ancestral Lines in the 1700s Using DNA Part 1 Curated Session https://youtu.be/bB7VJeCR6Bs 5866
Tim Janzen Tracing Ancestral Lines in the 1700s Using DNA Part 2 Curated Session https://youtu.be/scOtMyFULGI 3008
Ugo Perego Strengths and Limitations of Genetic Testing for Family History DNA Learning Center https://youtu.be/XkBK1y-LVaE 480
Ugo Perego A Personal Genetic Journey DNA Learning Center https://youtu.be/Lv9CSU50xCc 844
Ugo Perego Discovering Native American Ancestry through DNA Curated Session https://youtu.be/L1cs748ctx0 884
Ugo Perego Mitochondrial DNA: Our Maternally-Inherited Family History Curated Session https://youtu.be/Z5bPTUzewKU 599
Vivs Laliberte Introduction to Y DNA DNA Learning Center https://youtu.be/rURyECV5j6U 752
Yetunde Moronke Abiola 6% Nigerian: Tracing my Missing Nigerian Ancestor Curated Session https://youtu.be/YNQt60xKgyg 494

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Disclosure

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

Thank you so much.

DNA Purchases and Free Transfers

Genealogy Products and Services

Genealogy Research

Books

Haplogroup Matching: What It Does (and Doesn’t) Mean

“Our haplogroups (sort of) match, so that means we’re related, right?”

Well, maybe.

It depends.

Great Question

This is an oft-asked great question. Of course, the answer varies depending on the context of the question and what is meant by “related.” A haplogroup match may or may not be a valid match for genealogy. A “match” or a “not match” can mean different things.

The questions people often ask include:

  • Does a haplogroup have to match exactly in order for another person to either be considered a match to you?
  • If they don’t match exactly, can they still be considered as a possible match?
  • Conversely, can we rule someone out as a match on a specific genealogical line based on haplogroup alone?

These questions often arise in relation to DNA testing at Family Tree DNA, sometimes when people are trying to compare results to people who have haplogroup estimates, either at FamilyTreeDNA or from testing elsewhere.

In other words, if one person is haplogroup J and someone else is J1, either at the same vendor or at another, what does that tell us? This question pertains to both Y DNA and mitochondrial DNA tests no matter where you’ve tested.

Family Tree DNA offers different levels of Y DNA testing. Interpreting those match results can sometimes be confusing. The same is true for mitochondrial DNA, especially if your matches have not taken the full mitochondrial sequence (mtFull) test.

You might be comparing apples and oranges, or you might be comparing a whole orange (detailed test) with a few slices (haplogroup estimate.) How can you know, and how can you make sense of the results?

If you’re comparing a haplogroup between sources, such as a partial haplogroup determined by testing through a company like 23andMe or LivingDNA to complete tests taken at FamilyTreeDNA, the answer can be less than straightforward.

I discussed the difference between autosomal-based haplogroup assignments and actual testing of both Y DNA and mitochondrial DNA which result in haplogroup assignments, here. In a nutshell, both LivingDNA and 23andMe provide a high-level (base) haplogroup estimates based on a few specific probes when you purchase an autosomal test, but that’s not the same as deeper testing of the Y chromosome or mitochondrial DNA.

The answer to whether your haplogroup has to match is both “yes”, and “no.” Don’t you hate it when this happens?

Let’s look at different situations. But to begin with, there is at least one common answer.

Yes, Your Base Haplogroup Must Match

To even begin to look further for a common ancestor on either your Y DNA line (direct patrilineal) or direct mitochondrial matrilineal line (your mother’s mother’s mother’s line on up the tree), your base haplogroup much match.

In other words, you and your matches must all be in the same base haplogroup. Haplogroups are defined by the presence of specific combinations of mutations which are called SNPs (single nucleotide polymorphisms) in the Y DNA.

Click to enlarge images

All of these men on the Y DNA matches page are a branch of haplogroup R as shown under the Y-DNA Haplogroup column. There are more matches on down the page (not shown here) with more and different haplogroups. However, you’ll notice that all matches are a subset of haplogroup R, the base haplogroup.

The same is true for mitochondrial DNA haplogroups. You can see in this example that people who have not tested at the FMS (full mitochondrial sequence) level have a less specific haplogroup. The entire mitochondria must be tested in order to obtain a full haplogroup, such as J1c2f, as opposed to haplogroup J.

The Y DNA Terminal SNP Might Not Match

For Y DNA testers, when looking at your matches, even to close relatives, you may not have the same exact haplogroup because:

  • Some people may have tested at different levels
  • Some people in recent generations may have developed a SNP specific to their line.

In other words, haplogroups, testing level, and known genealogy all need to be considered, especially when the haplogroups are “close to each other” on the tree.

For Y DNA, FamilyTreeDNA:

  • Provides all testers with base haplogroup estimates based on STR tests, meaning 12-111 marker panels. These are very accurate estimates, but are also very high level.
  • Offers or has offered in the past both individual SNP tests and SNP packs or bundles that test individual SNPs indicating their presence or absence. This confirms a SNP or haplogroup, but only to that particular level.
  • Offers the Big Y-700 test, along with upgrades to previous Big Y test levels. There have been 3 versions of the Big Y test over time. The Big Y reads the entire gold standard region of the Y chromosome, reporting the known (named) SNP mutations customers do and don’t have. Additionally, the test reports any unnamed SNPs which are considered private variants until multiple men on the same branch of the Y DNA tree test with the same mutation. At that point, the mutation is named and becomes a haplogroup.

That’s why the answer is “no,” your haplogroup does not have to match exactly for you to actually be a match to each other.

A father and son could test, with one having an estimated haplogroup of R-M269 and the other taking the Big Y-700 resulting in a very different Terminal SNP, quite distant on the tree. Conversely, both men could take the Big Y and the son could have a different terminal SNP than the father because a mutation occurred between them. An autosomal DNA test would confirm that they are in fact, father and son.

However, a father and son who test and are placed in different base haplogroups – one in haplogroup I, and the other in haplogroup R, for example, has a very different situation. Their autosomal test would likely confirm that they are not father and son.

Having said this about paternity, especially if haplogroups are estimated and specific Y DNA SNP testing has not been done, don’t have a premature freak-out moment. Look at autosomal DNA, assuming you DO want to know. Y DNA alone should never be used to infer paternity without autosomal testing.

Let’s look at some examples.

Matches and Haplogroups

In the example shown above, you can see that several people have taken the Big Y test, so their SNP will be shown on further down the haplotree than those testers who have not. These are a leaf, not a branch.

You can see by looking at the Terminal SNP column, at far right, that people who have either taken the Big Y, or had any positive SNP test will have a value in the Terminal SNP column.

Anyone who has NOT taken the Big Y or taken a SNP test will have their base haplogroup estimated based on their STR tests. In this case, that estimate is R-M269. People with estimated haplogroups will not show anything in the Terminal SNP column.

It’s possible that if all of these men took the Big Y test that at least some would share the same Terminal SNP, and others might be closely related, only a branch or so different on the tree.

These men in this example are all descendants of Robert Estes born in England in 1555. All have Estes surnames, except for one man who is seeking the identity of his paternal line.

Let’s Look at the Tree

Our tester in the screenshot is haplogroup R-ZS3700 and matches men in the following haplogroups:

  • R-M269
  • R-L21
  • R-BY490
  • R-BY154784

There are a few additional haplogroups not shown because they are further down on his match list, so let’s just work with these for now.

After determining that these men are on the same branch of the Y tree, haplogroup R, the real question is how closely they are related and how close or far distant their terminal SNPs are located. More distance means the common ancestor is further back in time.

However, looks can be deceiving, especially if not everyone has tested to the same level.

The haplogroup furthest up in the tree, meaning the oldest, is R-M269, followed by the man who took the single SNP test for R-L21. Notice that R-M269 has more than 15,000 branches, so while this haplogroup could be used to rule out a match, R-M269 alone isn’t useful to determine genealogical matching.

There are a lot of branches between R-L21 and the next haplogroup on the tree.

Finally, here we go. Our tester is haplogroup R-ZS3700 that has one descendant branch. R-ZS3700 is a branch of R-BY490 that has 2 branches.

R-BY154784 is the last SNP on this branch of the tree. Our tester matches this man too.

Another way of viewing these matches is on the Block Tree provided for Big Y testers.

In this view, you can see that the Estes men all match back to about 18 “SNP generations” ago according to the legend at left, but they don’t match men further back in time who have taken the Big Y test.

Notice the up-arrow where haplogroups R-L21 and R-M269 are shown across the top of the display.

If you click on R-L21, you’ll see that that it appears about 61 SNP generations back in time.

Haplogroup R-M269 appears even further back in time, about 174 SNP generations.

The only reason you will match someone at either the R-L21 or R-M269 level is because you both descend from a common long-ago ancestral branch, hundreds to thousands of years in the past. You and they would both need to take either the Big Y-700 test for Y DNA, or the full sequence mitochondrial DNA test in order to determine your full haplogroup and see your list of matches based on those full sequences.

Public Trees

You can view FamilyTreeDNA‘s extensive public Y DNA tree by haplogroup, here.

You can view their public mitochondrial DNA tree by haplogroup, here.

And the Answer Is…

As you can see, there is no single answer to the question of haplogroup relationships. The answer is also partly defined by the context in which the question is asked.

  1. For two men to be “related” on the Y DNA patrilineal line, yes, minimally, the base haplogroup does have to match. Base haplogroups are defined by the leading letter, like “R” in the examples above.
  2. “Related” based on base haplogroup only can be hundreds or thousands of years back in time, but additional testing can resolve that question.
  3. “Related” can mean before the advent of surnames. However, a match to a man with the same surname suggests a common ancestor with that surname in the past several hundred years. That match could, however, be much closer in time.
  4. For two men to be closely related, assuming they have taken the same version of Big Y test, their haplogroup branches need to be fairly closely adjacent on the haplotree. FamilyTreeDNA will be introducing haplogroup aging soon, meaning SNP/haplogroup branch dates on their haplotree. At that time, the “distance” between men will be easier to understand.
  5. You can exclude a genealogical relationship on the direct paternal line if the two men involved have a different base haplogroup. This question often occurs when people are trying to understand if they “might match” with someone whose haplogroup has been estimated.
  6. This holds true as well for mitochondrial DNA haplogroups and matching.

And there you have it, six answers about what haplogroup matching does and does not mean.

The bottom line is that haplogroups can be a great starting point and you can sometimes eliminate people as potential matches.

However, to confirm genealogical matches, you’ll always need more granular testing that includes actual Y DNA or mitochondrial DNA matching based on marker mutation results, not just haplogroups.

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Genetic Genealogy at 20 Years: Where Have We Been, Where Are We Going and What’s Important?

Not only have we put 2020 in the rear-view mirror, thankfully, we’re at the 20-year, two-decade milestone. The point at which genetics was first added to the toolbox of genealogists.

It seems both like yesterday and forever ago. And yes, I’ve been here the whole time,  as a spectator, researcher, and active participant.

Let’s put this in perspective. On New Year’s Eve, right at midnight, in 2005, I was able to score kit number 50,000 at Family Tree DNA. I remember this because it seemed like such a bizarre thing to be doing at midnight on New Year’s Eve. But hey, we genealogists are what we are.

I knew that momentous kit number which seemed just HUGE at the time was on the threshold of being sold, because I had inadvertently purchased kit 49,997 a few minutes earlier.

Somehow kit 50,000 seemed like such a huge milestone, a landmark – so I quickly bought kits, 49,998, 49,999, and then…would I get it…YES…kit 50,000. Score!

That meant that in the 5 years FamilyTreeDNA had been in business, they had sold on an average of 10,000 kits per year, or 27 kits a day. Today, that’s a rounding error. Then it was momentous!

In reality, the sales were ramping up quickly, because very few kits were sold in 2000, and roughly 20,000 kits had been sold in 2005 alone. I know this because I purchased kit 28,429 during the holiday sale a year earlier.

Of course, I had no idea who I’d test with that momentous New Year’s Eve Y DNA kit, but I assuredly would find someone. A few months later, I embarked on a road trip to visit an elderly family member with that kit in tow. Thank goodness I did, and they agreed and swabbed on the spot, because they are gone today and with them, the story of the Y line and autosomal DNA of their branch.

In the past two decades, almost an entire generation has slipped away, and with them, an entire genealogical library held in their DNA.

Today, more than 40 million people have tested with the four major DNA testing companies, although we don’t know exactly how many.

Lots of people have had more time to focus on genealogy in 2020, so let’s take a look at what’s important? What’s going on and what matters beyond this month or year?

How has this industry changed in the last two decades, and where it is going?

Reflection

This seems like a good point to reflect a bit.

Professor Dan Bradley reflecting on early genetic research techniques in his lab at the Smurfit Institute of Genetics at Trinity College in Dublin. Photo by Roberta Estes

In the beginning – twenty years ago, there were two companies who stuck their toes in the consumer DNA testing water – Oxford Ancestors and Family Tree DNA. About the same time, Sorenson Genomics and GeneTree were also entering that space, although Sorenson was a nonprofit. Today, of those, only FamilyTreeDNA remains, having adapted with the changing times – adding more products, testing, and sophistication.

Bryan Sykes who founded Oxford Ancestors announced in 2018 that he was retiring to live abroad and subsequently passed away in 2020. The website still exists, but the company has announced that they have ceased sales and the database will remain open until Sept 30, 2021.

James Sorenson died in 2008 and the assets of Sorenson Molecular Genealogy Foundation, including the Sorenson database, were sold to Ancestry in 2012. Eventually, Ancestry removed the public database in 2015.

Ancestry dabbled in Y and mtDNA for a while, too, destroying that database in 2014.

Other companies, too many to remember or mention, have come and gone as well. Some of the various company names have been recycled or purchased, but aren’t the same companies today.

In the DNA space, it was keep up, change, die or be sold. Of course, there was the small matter of being able to sell enough DNA kits to make enough money to stay in business at all. DNA processing equipment and a lab are expensive. Not just the equipment, but also the expertise.

The Next Wave

As time moved forward, new players entered the landscape, comprising the “Big 4” testing companies that constitute the ponds where genealogists fish today.

23andMe was the first to introduce autosomal DNA testing and matching. Their goal and focus was always medical genetics, but they recognized the potential in genealogists before anyone else, and we flocked to purchase tests.

Ancestry settled on autosomal only and relies on the size of their database, a large body of genealogy subscribers, and a widespread “feel-good” marketing campaign to sell DNA kits as the gateway to “discover who you are.”

FamilyTreeDNA did and still does offer all 3 kinds of tests. Over the years, they have enhanced both the Y DNA and mitochondrial product offerings significantly and are still known as “the science company.” They are the only company to offer the full range of Y DNA tests, including their flagship Big Y-700, full sequence mitochondrial testing along with matching for both products. Their autosomal product is called Family Finder.

MyHeritage entered the DNA testing space a few years after the others as the dark horse that few expected to be successful – but they fooled everyone. They have acquired companies and partnered along the way which allowed them to add customers (Promethease) and tools (such as AutoCluster by Genetic Affairs), boosting their number of users. Of course, MyHeritage also offers users a records research subscription service that you can try for free.

In summary:

One of the wonderful things that happened was that some vendors began to accept compatible raw DNA autosomal data transfer files from other vendors. Today, FamilyTreeDNA, MyHeritage, and GEDmatch DO accept transfer files, while Ancestry and 23andMe do not.

The transfers and matching are free, but there are either minimal unlock or subscription plans for advanced features.

There are other testing companies, some with niche markets and others not so reputable. For this article, I’m focusing on the primary DNA testing companies that are useful for genealogy and mainstream companion third-party tools that complement and enhance those services.

The Single Biggest Change

As I look back, the single biggest change is that genetic genealogy evolved from the pariah of genealogy where DNA discussion was banned from the (now defunct) Rootsweb lists and summarily deleted for the first few years after introduction. I know, that’s hard to believe today.

Why, you ask?

Reasons varied from “just because” to “DNA is cheating” and then morphed into “because DNA might do terrible things like, maybe, suggest that a person really wasn’t related to an ancestor in a lineage society.”

Bottom line – fear and misunderstanding. Change is exceedingly difficult for humans, and DNA definitely moved the genealogy cheese.

From that awkward beginning, genetic genealogy organically became a “thing,” a specific application of genealogy. There was paper-trail traditional genealogy and then the genetic aspect. Today, for almost everyone, genealogy is “just another tool” in the genealogist’s toolbox, although it does require focused learning, just like any other tool.

DNA isn’t separate anymore, but is now an integral part of the genealogical whole. Having said that, DNA can’t solve all problems or answer all questions, but neither can traditional paper-trail genealogy. Together, each makes the other stronger and solves mysteries that neither can resolve alone.

Synergy.

I fully believe that we have still only scratched the surface of what’s possible.

Inheritance

As we talk about the various types of DNA testing and tools, here’s a quick graphic to remind you of how the different types of DNA are inherited.

  • Y DNA is inherited paternally for males only and informs us of the direct patrilineal (surname) line.
  • Mitochondrial DNA is inherited by everyone from their mothers and informs us of the mother’s matrilineal (mother’s mother’s mother’s) line.
  • Autosomal DNA can be inherited from potentially any ancestor in random but somewhat predictable amounts through both parents. The further back in time, the less identifiable DNA you’ll inherit from any specific ancestor. I wrote about that, here.

What’s Hot and What’s Not

Where should we be focused today and where is this industry going? What tools and articles popped up in 2020 to help further our genealogy addiction? I already published the most popular articles of 2020, here.

This industry started two decades ago with testing a few Y DNA and mitochondrial DNA markers, and we were utterly thrilled at the time. Both tests have advanced significantly and the prices have dropped like a stone. My first mitochondrial DNA test that tested only 400 locations cost more than $800 – back then.

Y DNA and mitochondrial DNA are still critically important to genetic genealogy. Both play unique roles and provide information that cannot be obtained through autosomal DNA testing. Today, relative to Y DNA and mitochondrial DNA, the biggest challenge, ironically, is educating newer genealogists about their potential who have never heard about anything other than autosomal, often ethnicity, testing.

We have to educate in order to overcome the cacophony of “don’t bother because you don’t get as many matches.”

That’s like saying “don’t use the right size wrench because the last one didn’t fit and it’s a bother to reach into the toolbox.” Not to mention that if everyone tested, there would be a lot more matches, but I digress.

If you don’t use the right tool, and all of the tools at your disposal, you’re not going to get the best result possible.

The genealogical proof standard, the gold standard for genealogy research, calls for “a reasonably exhaustive search,” and if you haven’t at least considered if or how Y
DNA
and mitochondrial DNA along with autosomal testing can or might help, then your search is not yet exhaustive.

I attempt to obtain the Y and mitochondrial DNA of every ancestral line. In the article, Search Techniques for Y and Mitochondrial DNA Test Candidates, I described several methodologies to find appropriate testing candidates.

Y DNA – 20 Years and Still Critically Important

Y DNA tracks the Y chromosome for males via the patrilineal (surname) line, providing matching and historical migration information.

We started 20 years ago testing 10 STR markers. Today, we begin at 37 markers, can upgrade to 67 or 111, but the preferred test is the Big Y which provides results for 700+ STR markers plus results from the entire gold standard region of the Y chromosome in order to provide the most refined results. This allows genealogists to use STR markers and SNP results together for various aspects of genealogy.

I created a Y DNA resource page, here, in order to provide a repository for Y DNA information and updates in one place. I would encourage anyone who can to order or upgrade to the Big Y-700 test which provides critical lineage information in addition to and beyond traditional STR testing. Additionally, the Big Y-700 test helps build the Y DNA haplotree which is growing by leaps and bounds.

More new SNPs are found and named EVERY SINGLE DAY today at FamilyTreeDNA than were named in the first several years combined. The 2006 SNP tree listed a grand total of 459 SNPs that defined the Y DNA tree at that time, according to the ISOGG Y DNA SNP tree. Goran Rundfeldt, head of R&D at FamilyTreeDNA posted this today:

2020 was an awful year in so many ways, but it was an unprecedented year for human paternal phylogenetic tree reconstruction. The FTDNA Haplotree or Great Tree of Mankind now includes:

37,534 branches with 12,696 added since 2019 – 51% growth!
defined by
349,097 SNPs with 131,820 added since 2019 – 61% growth!

In just one year, 207,536 SNPs were discovered and assigned FT SNP names. These SNPs will help define new branches and refine existing ones in the future.

The tree is constructed based on high coverage chromosome Y sequences from:
– More than 52,500 Big Y results
– Almost 4,000 NGS results from present-day anonymous men that participated in academic studies

Plus an additional 3,000 ancient DNA results from archaeological remains, of mixed quality and Y chromosome coverage at FamilyTreeDNA.

Wow, just wow.

These three new articles in 2020 will get you started on your Y DNA journey!

Mitochondrial DNA – Matrilineal Line of Humankind is Being Rewritten

The original Oxford Ancestor’s mitochondrial DNA test tested 400 locations. The original Family Tree DNA test tested around 1000 locations. Today, the full sequence mitochondrial DNA test is standard, testing the entire 16,569 locations of the mitochondria.

Mitochondrial DNA tracks your mother’s direct maternal, or matrilineal line. I’ve created a mitochondrial DNA resource page, here that includes easy step-by-step instructions for after you receive your results.

New articles in 2020 included the introduction of The Million Mito Project. 2021 should see the first results – including a paper currently in the works.

The Million Mito Project is rewriting the haplotree of womankind. The current haplotree has expanded substantially since the first handful of haplogroups thanks to thousands upon thousands of testers, but there is so much more information that can be extracted today.

Y and Mitochondrial Resources

If you don’t know of someone in your family to test for Y DNA or mitochondrial DNA for a specific ancestral line, you can always turn to the Y DNA projects at Family Tree DNA by searching here.

The search provides you with a list of projects available for a specific surname along with how many customers with that surname have tested. Looking at the individual Y DNA projects will show the earliest known ancestor of the surname line.

Another resource, WikiTree lists people who have tested for the Y DNA, mitochondrial DNA and autosomal DNA lines of specific ancestors.

Click on images to enlarge

On the left side, my maternal great-grandmother’s profile card, and on the right, my paternal great-great-grandfather. You can see that someone has tested for the mitochondrial DNA of Nora (OK, so it’s me) and the Y DNA of John Estes (definitely not me.)

MitoYDNA, a nonprofit volunteer organization created a comparison tool to replace Ysearch and Mitosearch when they bit the dust thanks to GDPR.

MitoYDNA accepts uploads from different sources and allows uploaders to not only match to each other, but to view the STR values for Y DNA and the mutation locations for the HVR1 and HVR2 regions of mitochondrial DNA. Mags Gaulden, one of the founders, explains in her article, What sets mitoYDNA apart from other DNA Databases?.

If you’ve tested at nonstandard companies, not realizing that they didn’t provide matching, or if you’ve tested at a company like Sorenson, Ancestry, and now Oxford Ancestors that is going out of business, uploading your results to mitoYDNA is a way to preserve your investment. PS – I still recommend testing at FamilyTreeDNA in order to receive detailed results and compare in their large database.

CentiMorgans – The Word of Two Decades

The world of autosomal DNA turns on the centimorgan (cM) measure. What is a centimorgan, exactly? I wrote about that unit of measure in the article Concepts – CentiMorgans, SNPs and Pickin’ Crab.

Fortunately, new tools and techniques make using cMs much easier. The Shared cM Project was updated this year, and the results incorporated into a wonderfully easy tool used to determine potential relationships at DNAPainter based on the number of shared centiMorgans.

Match quality and potential relationships are determined by the number of shared cMs, and the chromosome browser is the best tool to use for those comparisons.

Chromosome Browser – Genetics Tool to View Chromosome Matches

Chromosome browsers allow testers to view their matching cMs of DNA with other testers positioned on their own chromosomes.

My two cousins’ DNA where they match me on chromosomes 1-4, is shown above in blue and red at Family Tree DNA. It’s important to know where you match cousins, because if you match multiple cousins on the same segment, from the same side of your family (maternal or paternal), that’s suggestive of a common ancestor, with a few caveats.

Some people feel that a chromosome browser is an advanced tool, but I think it’s simply standard fare – kind of like driving a car. You need to learn how to drive initially, but after that, you don’t even think about it – you just get in and go. Here’s help learning how to drive that chromosome browser.

Triangulation – Science Plus Group DNA Matching Confirms Genealogy

The next logical step after learning to use a chromosome browser is triangulation. If fact, you’re seeing triangulation above, but don’t even realize it.

The purpose of genetic genealogy is to gather evidence to “prove” ancestral connections to either people or specific ancestors. In autosomal DNA, triangulation occurs when:

  • You match at least two other people (not close relatives)
  • On the same reasonably sized segment of DNA (generally 7 cM or greater)
  • And you can assign that segment to a common ancestor

The same two cousins are shown above, with triangulated segments bracketed at MyHeritage. I’ve identified the common ancestor with those cousins that those matching DNA segments descend from.

MyHeritage’s triangulation tool confirms by bracketing that these cousins also match each other on the same segment, which is the definition of triangulation.

I’ve written a lot about triangulation recently.

If you’d prefer a video, I recorded a “Top Tips” Facebook LIVE with MyHeritage.

Why is Ancestry missing from this list of triangulation articles? Ancestry does not offer a chromosome browser or segment information. Therefore, you can’t triangulate at Ancestry. You can, however, transfer your Ancestry DNA raw data file to either FamilyTreeDNA, MyHeritage, or GEDmatch, all three of which offer triangulation.

Step by step download/upload transfer instructions are found in this article:

Clustering Matches and Correlating Trees

Based on what we’ve seen over the past few years, we can no longer depend on the major vendors to provide all of the tools that genealogists want and need.

Of course, I would encourage you to stay with mainstream products being used by a significant number of community power users. As with anything, there is always someone out there that’s less than honorable.

2020 saw a lot of innovation and new tools introduced. Maybe that’s one good thing resulting from people being cooped up at home.

Third-party tools are making a huge difference in the world of genetic genealogy. My favorites are Genetic Affairs, their AutoCluster tool shown above, DNAPainter and DNAGedcom.

These articles should get you started with clustering.

If you like video resources, here’s a MyHeritage Facebook LIVE that I recorded about how to use AutoClusters:

I created a compiled resource article for your convenience, here:

I have not tried a newer tool, YourDNAFamily, that focuses only on 23andMe results although the creator has been a member of the genetic genealogy community for a long time.

Painting DNA Makes Chromosome Browsers and Triangulation Easy

DNAPainter takes the next step, providing a repository for all of your painted segments. In other words, DNAPainter is both a solution and a methodology for mass triangulation across all of your chromosomes.

Here’s a small group of people who match me on the same maternal segment of chromosome 1, including those two cousins in the chromosome browser and triangulation sections, above. We know that this segment descends from Philip Jacob Miller and his wife because we’ve been able to identify that couple as the most distant ancestor intersection in all of our trees.

It’s very helpful that DNAPainter has added the functionality of painting all of the maternal and paternal bucketed matches from Family Tree DNA.

All you need to do is to link your known matches to your tree in the proper place at FamilyTreeDNA, then they do the rest by using those DNA matches to indicate which of the rest of your matches are maternal and paternal. Instructions, here. You can then export the file and use it at DNAPainter to paint all of those matches on the correct maternal or paternal chromosomes.

Here’s an article providing all of the DNAPainter Instructions and Resources.

DNA Matches Plus Trees Enhance Genealogy

Of course, utilizing DNA matching plus finding common ancestors in trees is one of the primary purposes of genetic genealogy – right?

Vendors have linked the steps of matching DNA with matching ancestors in trees.

Genetic Affairs take this a step further. If you don’t have an ancestor in your tree, but your matches have common ancestors with each other, Genetic Affairs assembles those trees to provide you with those hints. Of course, that common ancestor might not be relevant to your genealogy, but it just might be too!

click to enlarge

This tree does not include me, but two of my matches descend from a common ancestor and that common ancestor between them might be a clue as to why I match both of them.

Ethnicity Continues to be Popular – But Is No Shortcut to Genealogy

Ethnicity is always popular. People want to “do their DNA” and find out where they come from. I understand. I really do. Who doesn’t just want an answer?

Of course, it’s not that simple, but that doesn’t mean it’s not disappointing to people who test for that purpose with high expectations. Hopefully, ethnicity will pique their curiosity and encourage engagement.

All four major vendors rolled out updated ethnicity results or related tools in 2020.

The future for ethnicity, I believe, will be held in integrated tools that allow us to use ethnicity results for genealogy, including being able to paint our ethnicity on our chromosomes as well as perform segment matching by ethnicity.

For example, if I carry an African segment on chromosome 1 from my father, and I match one person from my mother’s side and one from my father’s side on that same segment – one or the other of those people should also have that segment identified as African. That information would inform me as to which match is paternal and which is maternal

Not only that, this feature would help immensely tracking ancestors back in time and identifying their origins.

Will we ever get there? I don’t know. I’m not sure ethnicity is or can be accurate enough. We’ll see.

Transition to Digital and Online

Sometimes the future drags us kicking and screaming from the present.

With the imposed isolation of 2020, conferences quickly moved to an online presence. The genealogy community has all pulled together to make this work. The joke is that 2020’s most used phrase is “can you hear me?” I can vouch for that.

Of course while the year 2020 is over, the problem isn’t and is extending at least through the first half of 2021 and possibly longer. Conferences are planned months, up to a year, in advance and they can’t turn on a dime, so don’t even begin to expect in-person conferences until either late in 2021 or more likely, 2022 if all goes well this year.

I expect the future will eventually return to in-person conferences, but not entirely.

Finding ways to be more inclusive allows people who don’t want to or can’t travel or join in-person to participate.

I’ve recorded several sessions this year, mostly for 2021. Trust me, these could be a comedy, mostly of errors😊

I participated in four MyHeritage Facebook LIVE sessions in 2020 along with some other amazing speakers. This is what “live” events look like today!

Screenshot courtesy MyHeritage

A few days ago, I asked MyHeritage for a list of their LIVE sessions in 2020 and was shocked to learn that there were more than 90 in English, all free, and you can watch them anytime. Here’s the MyHeritage list.

By the way, every single one of the speakers is a volunteer, so say a big thank you to the speakers who make this possible, and to MyHeritage for the resources to make this free for everyone. If you’ve ever tried to coordinate anything like this, it’s anything but easy.

Additonally, I’ve created two Webinars this year for Legacy Family Tree Webinars.

Geoff Rasmussen put together the list of their top webinars for 2020, and I was pleased to see that I made the top 10! I’m sure there are MANY MORE you’d be interested in watching. Personally, I’m going to watch #6 yet today! Also, #9 and #22. You can always watch new webinars for free for a few days, and you can subscribe to watch all webinars, here.

The 2021 list of webinar speakers has been announced here, and while I’m not allowed to talk about something really fun that’s upcoming, let’s just say you definitely have something to look forward to in the springtime!

Also, don’t forget to register for RootsTech Connect which is entirely online and completely free, February 25-27, here.

Thank you to Penny Walters for creating this lovely graphic.

There are literally hundreds of speakers providing sessions in many languages for viewers around the world. I’ve heard the stats, but we can’t share them yet. Let me just say that you will be SHOCKED at the magnitude and reach of this conference. I’m talking dumbstruck!

During one of our zoom calls, one of the organizers says it feels like we’re constructing the plane as we’re flying, and I can confirm his observation – but we are getting it done – together! All hands on deck.

I’ll be presenting an advanced session about triangulation as well as a mini-session in the FamilySearch DNA Resource Center about finding your mother’s ancestors. I’ll share more information as it’s released and I can.

Companies and Owners Come & Go

You probably didn’t even notice some of these 2020 changes. Aside from the death of Bryan Sykes (RIP Bryan,) the big news and the even bigger unknown is the acquisition of Ancestry by Blackstone. Recently the CEO, Margo Georgiadis announced that she was stepping down. The Ancestry Board of Directors has announced an external search for a new CEO. All I can say is that very high on the priority list should be someone who IS a genealogist and who understands how DNA applies to genealogy.

Other changes included:

In the future, as genealogy and DNA testing becomes ever more popular and even more of a commodity, company sales and acquisitions will become more commonplace.

Some Companies Reduced Services and Cut Staff

I understand this too, but it’s painful. The layoffs occurred before Covid, so they didn’t result from Covid-related sales reductions. Let’s hope we see renewed investment after the Covid mess is over.

In a move that may or may not be related to an attempt to cut costs, Ancestry removed 6 and 7 cM matches from their users, freeing up processing resources, hardware, and storage requirements and thereby reducing costs.

I’m not going to beat this dead horse, because Ancestry is clearly not going to move on this issue, nor on that of the much-requested chromosome browser.

Later in the year, 23andMe also removed matches and other features, although, to their credit, they have restored at least part of this functionality and have provided ethnicity updates to V3 and V4 kits which wasn’t initially planned.

It’s also worth noting that early in 2020, 23andMe laid off 100 people as sales declined. Since that time, 23andMe has increasingly pushed consumers to pay to retest on their V5 chip.

About the same time, Ancestry also cut their workforce by about 6%, or about 100 people, also citing a slowdown in the consumer testing market. Ancestry also added a health product.

I’m not sure if we’ve reached market saturation or are simply seeing a leveling off. I wrote about that in DNA Testing Sales Decline: Reason and Reasons.

Of course, the pandemic economy where many people are either unemployed or insecure about their future isn’t helping.

The various companies need some product diversity to survive downturns. 23andMe is focused on medical research with partners who pay 23andMe for the DNA data of customers who opt-in, as does Ancestry.

Both Ancestry and MyHeritage provide subscription services for genealogy records.

FamilyTreeDNA is part of a larger company, GenebyGene whose genetics labs do processing for other companies and medical facilities.

A huge thank you to both MyHeritage and FamilyTreeDNA for NOT reducing services to customers in 2020.

Scientific Research Still Critical & Pushes Frontiers

Now that DNA testing has become a commodity, it’s easy to lose track of the fact that DNA testing is still a scientific endeavor that requires research to continue to move forward.

I’m still passionate about research after 20 years – maybe even more so now because there’s so much promise.

Research bleeds over into the consumer marketplace where products are improved and new features created allowing us to better track and understand our ancestors through their DNA that we and our family members inherit.

Here are a few of the research articles I published in 2020. You might notice a theme here – ancient DNA. What we can learn now due to new processing techniques is absolutely amazing. Labs can share files and information, providing the ability to “reprocess” the data, not the DNA itself, as more information and expertise becomes available.

Of course, in addition to this research, the Million Mito Project team is hard at work rewriting the tree of womankind.

If you’d like to participate, all you need to do is to either purchase a full sequence mitochondrial DNA kit at FamilyTreeDNA, or upgrade to the full sequence if you tested at a lower level previously.

Predictions

Predictions are risky business, but let me give it a shot.

Looking back a year, Covid wasn’t on the radar.

Looking back 5 years, neither Genetic Affairs nor DNAPainter were yet on the scene. DNAAdoption had just been formed in 2014 and DNAGedcom which was born out of DNAAdoption didn’t yet exist.

In other words, the most popular tools today didn’t exist yet.

GEDmatch, founded in 2010 by genealogists for genealogists was 5 years old, but was sold in December 2019 to Verogen.

We were begging Ancestry for a chromosome browser, and while we’ve pretty much given up beating them, because the horse is dead and they can sell DNA kits through ads focused elsewhere, that doesn’t mean genealogists still don’t need/want chromosome and segment based tools. Why, you’d think that Ancestry really doesn’t want us to break through those brick walls. That would be very bizarre, because every brick wall that falls reveals two more ancestors that need to be researched and spurs a frantic flurry of midnight searching. If you’re laughing right now, you know exactly what I mean!

Of course, if Ancestry provided a chromosome browser, it would cost development money for no additional revenue and their customer service reps would have to be able to support it. So from Ancestry’s perspective, there’s no good reason to provide us with that tool when they can sell kits without it. (Sigh.)

I’m not surprised by the management shift at Ancestry, and I wouldn’t be surprised to see several big players go public in the next decade, if not the next five years.

As companies increase in value, the number of private individuals who could afford to purchase the company decreases quickly, leaving private corporations as the only potential buyers, or becoming publicly held. Sometimes, that’s a good thing because investment dollars are infused into new product development.

What we desperately need, and I predict will happen one way or another is a marriage of individual tools and functions that exist separately today, with a dash of innovation. We need tools that will move beyond confirming existing ancestors – and will be able to identify ancestors through our DNA – out beyond each and every brick wall.

If a tester’s DNA matches to multiple people in a group descended from a particular previously unknown couple, and the timing and geography fits as well, that provides genealogical researchers with the hint they need to begin excavating the traditional records, looking for a connection.

In fact, this is exactly what happened with mitochondrial DNA – twice now. A match and a great deal of digging by one extremely persistent cousin resulting in identifying potential parents for a brick-wall ancestor. Autosomal DNA then confirmed that my DNA matched with 59 other individuals who descend from that couple through multiple children.

BUT, we couldn’t confirm those ancestors using autosomal DNA UNTIL WE HAD THE NAMES of the couple. DNA has the potential to reveal those names!

I wrote about that in Mitochondrial DNA Bulldozes Brick Wall and will be discussing it further in my RootsTech presentation.

The Challenge

We have most of the individual technology pieces today to get this done. Of course, the combined technological solution would require significant computing resources and processing power – just at the same time that vendors are desperately trying to pare costs to a minimum.

Some vendors simply aren’t interested, as I’ve already noted.

However, the winner, other than us genealogists, of course, will be the vendor who can either devise solutions or partner with others to create the right mix of tools that will combine matching, triangulation, and trees of your matches to each other, even if you don’t’ share a common ancestor.

We need to follow the DNA past the current end of the branch of our tree.

Each triangulated segment has an individual history that will lead not just to known ancestors, but to their unknown ancestors as well. We have reached critical mass in terms of how many people have tested – and more success would encourage more and more people to test.

There is a genetic path over every single brick wall in our genealogy.

Yes, I know that’s a bold statement. It’s not future Jetson’s flying-cars stuff. It’s doable – but it’s a matter of commitment, investment money, and finding a way to recoup that investment.

I don’t think it’s possible for the one-time purchase of a $39-$99 DNA test, especially when it’s not a loss-leader for something else like a records or data subscription (MyHeritage and Ancestry) or a medical research partnership (Ancestry and 23andMe.)

We’re performing these analysis processes manually and piecemeal today. It’s extremely inefficient and labor-intensive – which is why it often fails. People give up. And the process is painful, even when it does succeed.

This process has also been made increasingly difficult when some vendors block tools that help genealogists by downloading match and ancestral tree information. Before Ancestry closed access, I was creating theories based on common ancestors in my matches trees that weren’t in mine – then testing those theories both genetically (clusters, AutoTrees and ThruLines) and also by digging into traditional records to search for the genetic connection.

For example, I’m desperate to identify the parents of my James Lee Clarkson/Claxton, so I sorted my spreadsheet by surname and began evaluating everyone who had a Clarkson/Claxton in their tree in the 1700s in Virginia or North Carolina. But I can’t do that anymore now, either with a third-party tool or directly at Ancestry. Twenty million DNA kits sold for a minimum of $79 equals more than 1.5 billion dollars. Obviously, the issue here is not a lack of funds.

Including Y and mitochondrial DNA resources in our genetic toolbox not only confirms accuracy but also provides additional hints and clues.

Sometimes we start with Y DNA or mitochondrial DNA, and wind up using autosomal and sometimes the reverse. These are not competing products. It’s not either/or – it’s *and*.

Personally, I don’t expect the vendors to provide this game-changing complex functionality for free. I would be glad to pay for a subscription for top-of-the-line innovation and tools. In what other industry do consumers expect to pay for an item once and receive constant life-long innovations and upgrades? That doesn’t happen with software, phones nor with automobiles. I want vendors to be profitable so that they can invest in new tools that leverage the power of computing for genealogists to solve currently unsolvable problems.

Every single end-of-line ancestor in your tree represents a brick wall you need to overcome.

If you compare the cost of books, library visits, courthouse trips, and other research endeavors that often produce exactly nothing, these types of genetic tools would be both a godsend and an incredible value.

That’s it.

That’s the challenge, a gauntlet of sorts.

Who’s going to pick it up?

I can’t answer that question, but I can say that 23andMe can’t do this without supporting extensive trees, and Ancestry has shown absolutely no inclination to support segment data. You can’t achieve this goal without segment information or without trees.

Among the current players, that leaves two DNA testing companies and a few top-notch third parties as candidates – although – as the past has proven, the future is uncertain, fluid, and everchanging.

It will be interesting to see what I’m writing at the end of 2025, or maybe even at the end of 2021.

Stay tuned.

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Disclosure

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

Thank you so much.

DNA Purchases and Free Transfers

Genealogy Products and Services

Genealogy Research

Books

Y DNA Resources and Repository

I’ve created a Y DNA resource page with the information in this article, here, as a permanent location where you can find Y DNA information in one place – including:

  • Step-by-step guides about how to utilize Y DNA for your genealogy
  • Educational articles and links to the latest webinars
  • Articles about the science behind Y DNA
  • Ancient DNA
  • Success stories

Please feel free to share this resource or any of the links to individual articles with friends, genealogy groups, or on social media.

If you haven’t already taken a Y DNA test, and you’re a male (only males have a Y chromosome,) you can order one here. If you also purchase the Family Finder, autosomal test, those results can be used to search together.

What is Y DNA?

Y DNA is passed directly from fathers to their sons, as illustrated by the blue arrow, above. Daughters do not inherit the Y chromosome. The Y chromosome is what makes males, male.

Every son receives a Y chromosome from his father, who received it from his father, and so forth, on up the direct patrilineal line.

Comparatively, mitochondrial DNA, the pink arrow, is received by both sexes of children from the mother through the direct matrilineal line.

Autosomal DNA, the green arrow, is a combination of randomly inherited DNA from many ancestors that is inherited by both sexes of children from both parents. This article explains a bit more.

Y DNA has Unique Properties

The Y chromosome is never admixed with DNA from the mother, so the Y chromosome that the son receives is identical to the father’s Y chromosome except for occasional minor mutations that take place every few generations.

This lack of mixture with the mother’s DNA plus the occasional mutation is what makes the Y chromosome similar enough to match against other men from the same ancestors for hundreds or thousands of years back in time, and different enough to be useful for genealogy. The mutations can be tracked within extended families.

In western cultures, the Y chromosome path of inheritance is usually the same as the surname, which means that the Y chromosome is uniquely positioned to identify the direct biological patrilineal lineage of males.

Two different types of Y DNA tests can be ordered that work together to refine Y DNA results and connect testers to other men with common ancestors.

FamilyTreeDNA provides STR tests with their 37, 67 and 111 marker test panels, and comprehensive STR plus SNP testing with their Big Y-700 test.

click to enlarge

STR markers are used for genealogy matching, while SNP markers work with STR markers to refine genealogy further, plus provide a detailed haplogroup.

Think of a haplogroup as a genetic clan that tells you which genetic family group you belong to – both today and historically, before the advent of surnames.

This article, What is a Haplogroup? explains the basic concept of how haplogroups are determined.

In addition to the Y DNA test itself, Family Tree DNA provides matching to other testers in their database plus a group of comprehensive tools, shown on the dashboard above, to help testers utilize their results to their fullest potential.

You can order or upgrade a Y DNA test, here. If you also purchase the Family Finder, autosomal test, those results can be used to search together.

Step-by-Step – Using Your Y DNA Results

Let’s take a look at all of the features, functions, and tools that are available on your FamilyTreeDNA personal page.

What do those words mean? Here you go!

Come along while I step through evaluating Big Y test results.

Big Y Testing and Results

Why would you want to take a Big Y test and how can it help you?

While the Big Y-500 has been superseded by the Big Y-700 test today, you will still be interested in some of the underlying technology. STR matching still works the same way.

The Big Y-500 provided more than 500 STR markers and the Big Y-700 provides more than 700 – both significantly more than the 111 panel. The only way to receive these additional markers is by purchasing the Big Y test.

I have to tell you – I was skeptical when the Big Y-700 was introduced as the next step above the Big Y-500. I almost didn’t upgrade any kits – but I’m so very glad that I did. I’m not skeptical anymore.

This Y DNA tree rocks. A new visual format with your matches listed on their branches. Take a look!

Educational Articles

I’ve been writing about DNA for years and have selected several articles that you may find useful.

What kinds of information are available if you take a Y DNA test, and how can you use it for genealogy?

What if your father isn’t available to take a DNA test? How can you determine who else to test that will reveal your father’s Y DNA information?

Family Tree DNA shows the difference in the number of mutations between two men as “genetic distance.” Learn what that means and how it’s figured in this article.

Of course, there were changes right after I published the original Genetic Distance article. The only guarantees in life are death, taxes, and that something will change immediately after you publish.

Sometimes when we take DNA tests, or others do, we discover the unexpected. That’s always a possibility. Here’s the story of my brother who wasn’t my biological brother. If you’d like to read more about Dave’s story, type “Dear Dave” into the search box on my blog. Read the articles in publication order, and not without a box of Kleenex.

Often, what surprise matches mean is that you need to dig further.

The words paternal and patrilineal aren’t the same thing. Paternal refers to the paternal half of your family, where patrilineal is the direct father to father line.

Just because you don’t have any surname matches doesn’t necessarily mean it’s because of what you’re thinking.

Short tandem repeats (STRs) and single nucleotide polymorphisms (SNPs) aren’t the same thing and are used differently in genealogy.

Piecing together your ancestor’s Y DNA from descendants.

Haplogroups are something like our pedigree charts.

What does it mean when you have a zero for a marker value?

There’s more than one way to break down that brick wall. Here’s how I figured out which of 4 sons was my ancestor.

Just because you match the right line autosomally doesn’t mean it’s because you descend from the male child you think is your ancestor. Females gave their surnames to children born outside of a legal marriage which can lead to massive confusion. This is absolutely why you need to test the Y DNA of every single ancestral line.

When the direct patrilineal line isn’t the line you’re expecting.

You can now tell by looking at the flags on the haplotree where other people’s ancestral lines on your branch are from. This is especially useful if you’ve taken the Big Y test and can tell you if you’re hunting in the right location.

If you’re just now testing or tested in 2018 or after, you don’t need to read this article unless you’re interested in the improvements to the Big Y test over the years.

2019 was a banner year for discovery. 2020 was even more so, keeping up an amazing pace. I need to write a 2020 update article.

What is a terminal SNP? Hint – it’s not fatal😊

How the TIP calculator works and how to best interpret the results. Note that this tool is due for an update that incorporates more markers and SNP results too.

You can view the location of the Y DNA and mitochondrial DNA ancestors of people whose ethnicity you match.

Tools and Techniques

This free public tree is amazing, showing locations of each haplogroup and totals by haplogroup and country, including downstream branches.

Need to search for and find Y DNA candidates when you don’t know anyone from that line? Here’s how.

Yes, it’s still possible to resolve this issue using autosomal DNA. Non-matching Y DNA isn’t the end of the road, just a fork.

Science Meets Genealogy – Including Ancient DNA

Haplogroup C was an unexpected find in the Americas and reaches into South America.

Haplogroup C is found in several North American tribes.

Haplogroup C is found as far east as Nova Scotia.

Test by test, we made progress.

New testers, new branches. The research continues.

The discovery of haplogroup A00 was truly amazing when it occurred – the base of the phylotree in Africa.

The press release about the discovery of haplogroup A00.

In 2018, a living branch of A00 was discovered in Africa, and in 2020, an ancient DNA branch.

Did you know that haplogroups weren’t always known by their SNP names?

This brought the total of SNPs discovered by Family Tree DNA in mid-2018 to 153,000. I should contact the Research Center to see how many they have named at the end of 2020.

An academic paper split ancient haplogroup D, but then the phylogenetic research team at FamilyTreeDNA split it twice more! This might not sound exciting until you realize this redefines what we know about early man, in Africa and as he emerged from Africa.

Ancient DNA splits haplogroup P after analyzing the remains of two Jehai people from West Malaysia.

For years I doubted Kennewick Man’s DNA would ever be sequenced, but it finally was. Kennewick Man’s mitochondrial DNA haplogroup is X2a and his Y DNA was confirmed to Q-M3 in 2015.

Compare your own DNA to Vikings!

Twenty-seven Icelandic Viking skeletons tell a very interesting story.

Irish ancestors? Check your DNA and see if you match.

Ancestors from Hungary or Italy? Take a look. These remains have matches to people in various places throughout Europe.

The Y DNA story is no place near finished. Dr. Miguel Vilar, former Lead Scientist for National Geographic’s Genographic Project provides additional analysis and adds a theory.

Webinars

Y DNA Webinar at Legacy Family Tree Webinars – a 90-minute webinar for those who prefer watching to learn! It’s not free, but you can subscribe here.

Success Stories and Genealogy Discoveries

Almost everyone has their own Y DNA story of discovery. Because the Y DNA follows the surname line, Y DNA testing often helps push those lines back a generation, or two, or four. When STR markers fail to be enough, we can turn to the Big Y-700 test which provides SNP markers down to the very tip of the leaves in the Y DNA tree. Often, but not always, family-defining SNP branches will occur which are much more stable and reliable than STR mutations – although SNPs and STRs should be used together.

Methodologies to find ancestral lines to test, or maybe descendants who have already tested.

DNA testing reveals an unexpected mystery several hundred years old.

When I write each of my “52 Ancestor” stories, I include genetic information, for the ancestor and their descendants, when I can. Jacob was special because, in addition to being able to identify his autosomal DNA, his Y DNA matches the ancient DNA of the Yamnaya people. You can read about his Y DNA story in Jakob Lenz (1748-1821), Vinedresser.

Please feel free to add your success stories in the comments.

What About You?

You never know what you’re going to discover when you test your Y DNA. If you’re a female, you’ll need to find a male that descends from the line you want to test via all males to take the Y DNA test on your behalf. Of course, if you want to test your father’s line, your father, or a brother through that father, or your uncle, your father’s brother, would be good candidates.

What will you be able to discover? Who will the earliest known ancestor with that same surname be among your matches? Will you be able to break down a long-standing brick wall? You’ll never know if you don’t test.

You can click here to upgrade an existing test or order a Y DNA test.

Share the Love

You can always forward these articles to friends or share by posting links on social media. Who do you know that might be interested?

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Disclosure

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

Thank you so much.

DNA Purchases and Free Transfers

Genealogy Products and Services

Genealogy Research

Books