Category Archives: 23andMe

Comparing DNA Results – Different Tests at the Same Testing Company

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Several people have asked about different tests at the same DNA testing company. They wondered if matching is affected, meaning whether your matches are different if you have two different tests at the same company. Specifically, they asked if you are better off purchasing a test AT a DNA testing vendor that allows uploads, rather than uploading a test from a different vendor. Does it make a difference to the tester or their matches? Do they have the same matches?

These are great questions, and the answer isn’t conclusive. It varies based on several factors.

Having multiple tests at the same DNA testing company can occur in three ways:

  • The same person tests twice at the same DNA testing company.
  • The same person tests once at the DNA testing company and uploads a test from a different testing company. Only two of the primary four DNA testing companies accept uploads from other vendors – FamilyTreeDNA and MyHeritage.
  • The same person uploads two different files from other DNA testing companies to the DNA testing company in question. For example, the DNA company could be FamilyTreeDNA and the two uploaded DNA files could be from either MyHeritage, 23andMe or Ancestry.

All DNA testing companies allow users to download their raw DNA data files. This enables the tester to upload their DNA file to the vendors who accept uploaded files. Both FamilyTreeDNA and MyHeritage provide matching for free, but advanced tools require a small unlock fee of $19 and $29, respectively.

Testing Company Accepts Uploads from Other Companies Download Upload Instructions
23andMe No Instructions here
Ancestry No Instructions here
FamilyTreeDNA Yes, some Instructions here
MyHeritage Yes, some Instructions here

I wrote about developing a DNA testing and transfer/upload strategy, here, and about which companies accept which tests, here.

Not all DNA files are created equal. Therefore, not all files from vendors are compatible with other vendors for various reasons.

Multiple Tests at the Same DNA Testing Company

I have at least two tests at each of the four major vendors. I did this for research purposes, meaning to write articles to share with you.

If you actually test twice at a vendor, meaning purchase two separate tests and take them yourself, you will have two test results at that testing company. At some companies, specifically 23andMe, if you purchase a new test through their “upgrade” procedure, you won’t have two tests, just the newer one.

However, if you’re testing at the DNA testing company, and also uploading, I generally don’t recommend more than one test at each vendor. All it really does is clog up people’s match lists with no or little additional benefit. At 23andMe, with their restrictions on the size of your match list, if everyone had two tests, the effective match limit would be half of their stated limit of about 1500 matches for earlier testers and about 5000 for current testers with subscriptions.

So, in essence, I’m telling you to “do as I say, not as I do.” We all have better things to do with our money rather pay for the same test twice. If you haven’t tested your Y-DNA or mitochondrial DNA, that’s much more beneficial than two autosomal tests at one vendor.

Chips and Chip Evolution

Before we begin the side-by-side comparison, let’s briefly discuss DNA testing chips and how they work.

Each DNA testing company purchases DNA processing equipment. Illumina is the big dog in this arena. Illumina defines the capacity and structure of each chip. In part, how the testing companies use that capacity, or space on each chip, is up to each company. This means that the different testing companies test many of the same autosomal DNA SNP locations, but not all of the same locations.

Furthermore, the individual testing companies can specify a number of “other” locations to be included on their chip, up to the chip maximum size limit. The testing companies who offer Y-DNA or mitochondrial DNA haplogroups from autosomal tests use part of their chip array space for selected known haplogroup-defining SNP locations. This does NOT mean that Y-DNA or mitochondrial DNA is autosomal, just that the testing company used part of their chip array space to target these SNPs in your genome. Of course, for your most refined haplogroup and Y-DNA or mitochondrial DNA matching, you have to take those specific tests at FamilyTreeDNA .

This means that each testing company includes and reports many of the same, but also some different SNP locations when they scan your DNA.

In the lab, after your DNA is extracted from either your saliva or the cheek swab, it’s placed on this array chip which is then placed in the processing equipment.

There are several steps in processing your DNA. Each DNA location specified on the chip is scanned and read multiple times, and the results are recorded. The final output is the raw DNA results file that you see if/when you download your raw DNA file.

Here’s an example from my file. The RSID is the reference SNP cluster ID which is the naming convention used for specific SNPs. It’s not relevant to you, but it is to the lab, along with the chromosome number and position, which is in essence the address on the chromosome.

In the Result column, your file reports one nucleotide (T, A, C or G) that you inherited from each parent at each tested position. They are not listed in “parent order” because your DNA is not organized in that fashion. There’s no way for the lab to know which nucleotide came from which parent, unless they are the same, of course. You can read about nucleotides, here.

When you upload your raw DNA file to a different DNA testing company (vendor), they have to work with a file that isn’t entirely compatible with the files they generate, or the other files uploaded from other DNA testing companies.

In addition to dealing with different file formats and contents from multiple DNA vendors, companies change their own chips and file structure from time to time. In some cases, it’s a forced change by the chip manufacturer. Other times, the vendors want to include different locations or make improvements. For example, with 23andMe’s focus on health, they probably add new medically related SNP locations regularly. Regardless of why, some DNA files include locations not included in other files and are not 100% compatible.

Looking at the first few entries in my example file above, let’s say that the testing vendor included the first ten positions, but an uploaded file from another company did not. Or perhaps the chip changed, and a different version of the company’s own file contains different positions.

DNA testing companies have to “fill in the blanks” for compatibility, and they do this using a technique called imputation. Illumina forced their customers to adopt imputation in 2017 when they dropped the capacity of their chip. I was initially quite skeptical, but imputation has worked surprisingly well. Some of the matching differences you will see when comparing the results of two different DNA files is a result of imputation.

I wrote about imputation in an early article here. Please note the companies have fixed many issues with imputation and improved matching greatly, but the concepts and imputation processes still apply. The downloaded raw data files are your results BEFORE imputation, meaning that it’s up to any company where you upload to process your raw file in the same way they would process a file that they generated. A lot goes on behind the scenes when you upload a file to a DNA testing company.

At both 23andMe and Ancestry, you know that all of your matches tested there, meaning they did not upload a file from another testing company. You don’t know and can’t tell what chip was utilized when your matches tested. The only way to determine a chip testing version, aside from knowing the date or remembering the chip version from when you tested, is to look at the beginning of the raw data download file, although not all files contain that information.

Ok, now that you understand the landscape, let’s look at my results at each company.

23andMe

I tested twice at 23andMe on two different chip versions, V3 and V4, which tested some different locations of my DNA. Neither of these chips is the current version. I originally tested twice to evaluate the differences between the two test versions which you can read about, here.

23andMe named their ethnicity results Ancestry Composition.

They last updated my V3 test’s Ancestry Composition results on July 28, 2021.

The percentages are shown at left, and the country locations are highlighted at right for my 23andMe V3 test.

Click to enlarge any graphic

The 23andMe V4 test was also updated for the last time on July 28, 2021.

The ethnicity results differ substantially between the two chip versions, even though they were both updated on the same date.

In October of 2020, in an effort to “encourage” their customers to pay for a new test on their V5 chip, 23andMe announced that there would be no ethnicity updates on older tests. So, I really don’t know for sure when my tests were actually updated. Just note how different the results are. It’s also worth mentioning that 23andMe does not show trace amounts on their map, so even though my Indigenous American results were found, they aren’t displayed on the map.

Indigenous is, however, shown in yellow on their DNA Chromosome Painting.

No other testing company restricts updates, penalizing their customers who purchased earlier versions of tests.

Matches at 23andMe

23andMe limits your matches to about 1500 unless you have purchased the current test, including health AND pay for an annual $69 subscription which buys you about 5000 matches. I have not purchased this test.

Your number of actual matches displayed/retained is also affected by how many people you have communicated with, or at least initiated communications with. 23andMe does not roll those people off of your match list.

I have 1803 matches on both of my tests, meaning I’ve reached out to about 300 people who would have otherwise been removed from my match list. 23andMe retains your highest matches, deleting lower matches after you reach the maximum match threshold.

I’ve randomly evaluated several of the same matches at each vendor, at least five maternal and five paternal, separated by a blank row. I wanted to determine whether they match me on the same number of centimorgans, meaning the same amount of DNA, on both tests, and the same number of segments.

Match 23and Me V3 23and Me V4
Patricia 292 cM – 12 segments Same as V3
Joe 148 cM, 8 segments Same
Emily 73 cM, 4 segs 72 cM, 4 seg
Roland 27 cM, 1 seg Same
Ian 62 cM, 4 seg Same
Stacy 469 cM, 16 segments 482 cM, 16 segments
Harold 134 cM, 6 segments Same
Dean 69 cM, 3 seg Same
Carl 95 cM, 4 seg Same
Debbie 83 cM, 4 seg 84 cM, 4 seg

As you can see, the matches are either exact or xclose.

Please note that bolded matches are also found at another company. I will include a summary table at the end comparing the same match across multiple vendors.

23and Me Summary

The 23andMe V3 and V4 match results are very close. Since the match limit is the same, and the results are so close between tests, they are essentially identical in terms of matching.

The ethnicity results are similar, but the V4 test reflects a broader region. Italian baffles me in both versions.

Ethnicity should never be taken at face value at any DNA testing company, especially with smaller percentages which could be noise or a combination of other regions which just happens to resemble Italy, in my case.

I don’t know what type of comparison the current chip would yield since I suspect it has more medical and less genealogical SNPs on board.

Reprocessing Tests

This is probably a good place to note that it’s very expensive for any company to update their customer’s ethnicity results because every single customer’s DNA results file must be completely rerun. Note that this does not mean their DNA itself is retested. The output raw data file is reprocessed using a new algorithm.

Rerunning means reprocessing that specific portion of every test, meaning the vendors must rent “time in the cloud.” We are talking millions of dollars for each run. I don’t know how much it costs per test, but think about the expense if it takes $1 to rerun each test in the vendor’s database. Ancestry has more than 20 million tests.

While we, as consumers, are always chomping at the bit for new and better ethnicity results – the testing companies need to be sure it really is “better,” not just different before they invest the money to reprocess and update results.

This is probably why 23andMe decided to cease updating older kits. The newer tests require a subscription which is recurring revenue.

The same is true when DNA testing companies need to rematch their entire user base. This happens when the criteria for matching changes. For example, Ancestry purged a large number of matches for all of their customers back in 2020. While match algorithm changes necessitate rematching, with associated costs, this change also provided Ancestry with the huge benefit of eliminating approximately half of their customer’s matches. This freed up storage space, either physically in their data center or space rented in the cloud, representing substantial cost-savings.

How long can a DNA testing company reasonably be expected to continue investing in a product which never generates additional revenue but for which the maintenance and reinvestment costs never end?

Ancestry and MyHeritage both hope to offset the expenses of maintaining their customer’s DNA tests and providing free updates by selling subscriptions to their record services. 23andMe wants you to purchase a new test and a yearly subscription. FamilyTreeDNA wants you to purchase a Big Y-DNA and mitochondrial DNA test.

OK, now let’s look at my matches at Ancestry.

Ancestry

I’ve taken two Ancestry tests, V1 and V2. There were some differences, which I wrote about here and here. V2 is no longer the current chip.

Except for 23andMe who wants their customers to purchase their most current test, the other companies no longer routinely announce new chip versions. They just go about their business. The only way you know that a vendor actually changed something is when the other companies who accept uploads suddenly encounter an issue with file formats. It always takes a few weeks to sort that out.

My Ancestry V1 test’s ethnicity results don’t show my Native American ethnicity.

Ancestry results were updated in June 2022

However, my V2 results do include Native American ethnicity.

Matches at Ancestry

I have many more matches on my V1 test at Ancestry because I took steps to preserve my smaller matches when Ancestry initiated its massive purge in 2020. I wrote about that here and here.

Ancestry’s SideView breaks matches down into maternal, paternal, and unassigned based on your side selection. You tell Ancestry which side is which. You may be able to determine which “side” is maternal or paternal either by your ethnicity or shared matches. While SideView is not always accurate, it’s a good place to begin.

Match Category Ancestry V1 Test Ancestry V2 Test
Maternal 15,587 15,116
Paternal 42,247 41,870
Both 2 2
Unassigned 48,999 4,127
Total 106,835 61,115

Ancestry either displays all your matches or your matches by side, which I used to compile the table above. I suspect that Ancestry is not assigning any of the smaller preserved matches to “sides” based on the numbers above.

Ancestry implemented a process called Timber that removes DNA that they feel is “too matchy,” meaning you match enough people in this region that they think it’s a pileup region for you personally, and therefore not useful. In some cases, enough DNA is removed causing that person to no longer be considered a match because they fall beneath the match threshold. I am not a fan of Timber.

Your match amount shown is AFTER Timber has removed those segments. Unweighted shared DNA is your pre-Timber match amount.

You can view the Unweighted shared DNA by clicking on the amount of shared DNA on your match list.

You can read Ancestry’s Matching White Paper, here.

Let’s take a look at my matches. I’ve listed both weighted and unweighted where they are different.

Match Ancestry V1 Ancestry V2
Michael 755 cM, 35 seg 737 cM, 33 seg
Edward 66 cM, 4 seg (unweighted 86 cM) 65 cM, 4 seg (unweighted 86 cM)
Tom 59 cM, 3 seg (unweighted 63) Same
Jonathon 43 cM, 4 seg, (unweighted 52 cM) Same
Matthew 20 cM, 2 seg (unweighted 35 cM) Same
Harold 132 cM, 7 seg 135 cM, 6 seg
Dean 67 cM, 4 seg (unweighted 78 cM) 66 cM, 4 seg (unweighted 78 cM)
Debbie 93 cM, 5 seg Same
Valli 142 cM, 3 seg Same
Jared 20 cM, 1 seg (unweighted 22 cM) Same

Timber only removes DNA when the match is under 90 cM. Almost every match under 90 cM has some DNA removed.

Ancestry Summary

The results of the two Ancestry tests are very close.

In some circumstances, no DNA is removed by Timber, so the unweighted is the same as the weighted. However, in other cases, a significant amount is removed. 15 cM of Matthew’s 35 cM was removed by Timber, reducing his total to 20 cM.

Remember that Ancestry does not show shared matches unless they are greater than 20 cM, which is different than any other DNA testing company.

At one point, Ancestry was selling a health test that was also a genealogy test. That test utilized a different chip that is not accepted for uploads by other vendors. The results of that test might well be different that the “normal” Ancestry tests focused on genealogy. The Ancestry health test is no longer offered.

Companies that Accept Uploads

DNA testing companies that accept uploaded DNA files from other DNA testing companies need to process the uploaded file, just like a file that is generated in their own lab. Of course, they must deal with the differences between uploaded files and their own file format. The processing includes imputation and formulates the uploaded file so that it works with the tools that they provide for their customers, including ethnicity (by whatever name they use) matching, family matching (bucketing), advanced matching, the match matrix, triangulation, AutoClusters, Theories of Family Relativity, and other advanced tools.

Of course, the testing company accepting uploads can only work with the DNA locations provided by the original DNA testing company in the uploaded file.

Matching and some additional tools are free to uploaders, but advanced tools require an inexpensive unlock.

FamilyTreeDNA

I took a test at FamilyTreeDNA, plus uploaded a copy of both of my Ancestry DNA files.

FamilyTreeDNA named their population (ethnicity) test myOrigins and the current version is V3. I wrote about the rollout and comparison in September of 2020, here.

My DNA test taken at FamilyTreeDNA, above, reveals Native American segments that match reference populations found both in North and South America and the Caribbean Islands.

At FamilyTreeDNA, my Ancestry V1 uploaded file results show Native American population matches only in North America.

Interestingly, my Ancestry V1 file processed AT Ancestry did not reveal Native American ancestry, but the same file uploaded to and processed at FamilyTreeDNA did show Native American results, reflecting the difference between the vendors’ internal algorithms and reference populations utilized.

My myOrigins results from my Ancestry V2 uploaded file at FamilyTreeDNA also include my North American Native American segments. The V2 test also showed Native American ethnicity at Ancestry, so clearly something changed in Ancestry’s algorithm, locations tested, and/or reference populations between V1 and V2.

Fortunately, FamilyTreeDNA provides both chromosome painting and a population download file so I can match those Native segments with my autosomal matches to identify which of my ancestors contributed those specific segments.

One of my Native segments is shown in pink on Chromosome1. My mother has a Native segment in exactly the same location, so I know that this segment originated with my mother’s ancestors.

I downloaded the myOrigins population segment file and painted my results at DNAPainter, along with the matches where I can identify our common ancestor. This allowed me to pinpoint the ancestral line that contributed this Native segment in my maternal line. You can read about using DNAPainter, here.

FamilyTreeDNA Matches

I have significantly more matches at FamilyTreeDNA on their test than on either of my Ancestry tests that I uploaded. However, nearly the same number are maternally or paternally assigned through Family Matching, with the remainder unassigned. You can read about Family Matching here.

Match Category FamilyTreeDNA Test Ancestry V1 at FamilyTreeDNA Ancestry V2 at FamilyTreeDNA
Paternal 3,479 3,572 3,422
Maternal 1,549 1,536 1,477
Both 3 3 3
All 8,154 6,397 6,579

Family matching, aka bucketing, automatically assigns my matches as maternal and paternal by linking known relatives to their place in my tree.

I completed the following match chart using my original test taken at FamilyTreeDNA, plus the same match at FamilyTreeDNA for both of my Ancestry tests.

In other words, Cheryl matched me at 467 cM on 21 segments on the original test taken at FamilyTreeDNA. She matched me on 473 cM and 21 segments on my Ancestry V1 test uploaded to FamilyTreeDNA and on 483 cM and 22 segments on the Ancestry V2 test uploaded to FamilyTreeDNA.

Match FamilyTreeDNA Ancestry V1 at FTDNA Ancestry V2 at FTDNA
Cheryl 467 cM, 21 seg 473 cM, 21 seg 483 cM, 22 seg
Patricia 195 cM, 11 seg 189 cM, 11 seg 188 cM, 11 seg
Tom 77 cM, 4 seg 71 cM, 4 seg 76 cM, 4 seg
Thomas 72 cM, 3 seg 71 cM, 3 seg 74 cM, 3 seg
Roland 29 cM, 1 seg 35 cM, 2 seg 35 cM, 2 seg
Rex 62 cM, 4 seg 55 cM, 3 seg 57 cM, 3 seg
Don 395 cM, 18 seg 362 cM, 15 seg 398 cM, 18 seg
Ian 64 cM, 4 seg 56 cM, 4 seg 64 cM, 4 seg
Stacy 490 cM, 18 seg 494 cM, 15 seg 489 cM, 14 seg
Harold 127 cM, 5 cM 133 cM, 6 seg 143 cM, 6 seg
Dean 81 cM, 4 seg 75 cM, 3 seg 83 cM, 4 seg
Carl 103 cM, 4 seg 101 cM, 4 seg 102 cM, 4 seg
Debbie 99 cM, 5 seg 97 cM, 5 seg 99 cM, 5 seg
David 373 cM, 16 seg 435 cM, 19 seg 417 cM, 18 seg
Amos 176 cM, 7 seg 177 cM. 8 seg 177 cM, 7 seg
Buster 387 cM, 15 seg 396 cM, 16 seg 402 cM, 17 seg
Charlene 461 cM, 21 seg 450 cM, 21 seg 448 cM, 20 seg
Carol 65 cM, 6 seg 64 cM, 6 seg 65 cM, 6 seg

I have tested many of my cousins at FamilyTreeDNA and encouraged others to test or upload. I’ve attempted to include enough people so that I can have common matches at least at one other DNA testing company for comparison.

FamilyTreeDNA Summary

The matches are relatively close, with a few being exact.

Interestingly, some of the segment counts are different. In most cases, this results from one segment being broken into multiple segments by one or more of the tests, but not always. In the couple that I checked, the entire segment seems to descend from the same ancestral couple, so the break is likely a result of not all of the same DNA locations being tested, plus the limits of imputation.

MyHeritage

I have two tests at MyHeritage. One taken at MyHeritage, and an uploaded file from FamilyTreeDNA.

MyHeritage displays both ethnicity results and Genetic Groups which maps groups of people that you match. I left the Genetic Groups setting at the highest confidence level. Shifting it to lower displays additional Genetic Groups, some of which overlap with or are within ethnicity regions.

My test taken at MyHeritage, above, shows several ethnicities and Genetic Groups, but no Native American.

My FamilyTreeDNA kit processed at MyHeritage shows the same ethnicity regions, one additional Genetic Group, plus Native American heritage in the Amazon which is rather surprising given that I don’t show Native in North American regions where I’m positive my Native ancestors lived.

MyHeritage Matching

At MyHeritage, I compared the results of the test I took with MyHeritage, and a test I uploaded from FamilyTreeDNA. Fewer than half of my matches can be assigned to a parent via shared matching.

Matches MyHeritage Test FamilyTreeDNA at MyHeritage
Paternal 4,422 6,501
Maternal 2,660 3,655
Total 13,233 16,147

I have rounded my matches at MyHeritage to the closest cM.

Match MyHeritage Test FamilyTreeDNA at MyHeritage
Michael 801 cM, 32 seg 823 cM, 31 segments
Cheryl 467 cM, 23 seg 477 cM, 23 seg
Roland No match 28 cM, 1 seg
Patty 156 cM, 9 seg 151 cM, 9 seg
Rex 43 cM, 4 seg 53 cM, 3 seg
Don 369 cM, 16 seg 382 cM, 17 seg
 
David 449 cM, 17 seg 460 cM, 17 seg
Charlene 454 cM, 23 seg 477 cM, 24 seg
Buster 408 cM, 15 seg 410 cM, 16 seg
Amos 183 cM, 8 seg Same
Carol 78 cM, 6 seg 87 cM, 7 seg

MyHeritage Summary

I was surprised to discover that Roland had no match with the MyHeritage test, but did with the FamilyTreeDNA test. I wonder if this is a searching or matching glitch, especially since both companies use the same chip. 28 cM in one segment is a reasonably large match, and even if it was divided in two, it would still be over the matching threshold. I know this is a valid match because Roland triangulates with me and several cousins, I’m positive of our common ancestor, and he also matches me at both FamilyTreeDNA and 23andMe.

Other than that, the matches are reasonably close, with one being exact.

Your Matches Aren’t Everyplace

I unsuccessfully searched for someone who was a match to me in all four databases. Ancestry does not permit match downloads, so I had to search manually. People don’t always use the same names in different databases.

Surprisingly, I was unable to find one match who is in all of the databases. Many people only suggest testing at Ancestry because they have the largest database, but if you look at the following comparison chart that I’ve created, you’ll see that 16 of 26 people, or 62% were not at Ancestry. Conversely, many people were at Ancestry and not elsewhere. I could not find five maternal and five paternal matches at Ancestry that I could identify as matches in another database. 40% were not elsewhere.

If you think for one minute that it doesn’t matter for genealogy if you’re in all four major databases, please reconsider. It surely does matter.

Every single vendor has matches that the others don’t. Substantial, important matches. I have found first and second-cousin matches in every database that weren’t elsewhere.

Many of the original testers have passed away and can’t test again. My mother can never test at either 23andMe or Ancestry, but she is at both FamilyTreeDNA and MyHeritage because I could upgrade her kit at FamilyTreeDNA after she died. I uploaded her to MyHeritage. Of course, because she is a generation closer to our ancestors, she has many valuable matches that I don’t.

Each vendor provides either an email address or a messaging platform for you to contact your matches. Don’t be discouraged if they don’t answer. Just today, I received a reply that was years in the making.

Genealogists hope for immediate gratification, but we are actually in this for the long game. Play it with every tool at your disposal.

The Answer

Does it matter if you test at a DNA testing company, or upload a file?

I know this was a very long answer to what my readers hoped was a simple yes or no question.

There is no consistent answer at either FamilyTreeDNA or MyHeritage, the two DNA testing companies that accept uploads. Be sure you’re in both databases. My closest two matches that I did not test were found at MyHeritage. Here’s a direct link to upload at MyHeritage.

Of the vendors, those two should be the closest to each other because they are both processed in the GenebyGene lab, but again, the actual chip version, when the test was originally taken, and each vendor’s internal processing will result in differences. Neither the original test at the DNA testing company nor the uploaded files have consistently higher or lower matches. Neither type of test or upload appears to be universally more or less accurate. Differences in either direction seem to occur on a match-by-match basis. Many are so close as to be virtually equivalent, with a few seemingly random exceptions. Of course, we always have to consider Timber.

If you upload, unlock the advanced features at both FamilyTreeDNA and MyHeritage.

If you upload to a DNA testing company, you may discover in the future that some features and functions will only be available to original testers.

Personally, if I had the option, I would test at the company directly simply because it eliminates or at least reduces the possibility of future incompatibilities – with the exception of 23andMe which has chosen to not provide consistent updates to older tests. I’m incredibly grateful I didn’t test my mother or now deceased family members at 23andMe, and only there. I would be heartsick, heartbroken, and furious.

Our DNA is an extremely valuable resource for our genealogy. It’s the gift that truly keeps on giving, day after day, even when other records don’t exist. Be sure you and your family members are in each database one way or another, and test your Y-DNA (for males) and mitochondrial DNA (for everyone) to have a complete arsenal at your disposal.

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

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

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

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

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

Full Siblings

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

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

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

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

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

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

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

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

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

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

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

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

Half-Siblings

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

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

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

Hints that you are only half-siblings include:

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

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

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

Three-Quarter Siblings

This gets a little more complicated.

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

Let’s use a real-life example.

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

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

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

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

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

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

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

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

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

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

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

Three-quarter sibling situations are very challenging.

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

Step-Siblings

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

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

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

Adopted Siblings

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

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

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

Donor-Conceived Siblings

Donor-conceived siblings could be:

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

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

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

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

Twins or Multiple Birth Siblings

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

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

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

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

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

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

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

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

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

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

Siblings

Whoever thought there would be so many kinds of siblings!

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

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So, You Want to Become a Professional Genetic Genealogist

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

That’s actually two separate questions.

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

What It’s Not

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

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

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

The difference between genetic genealogy more broadly and IGG is:

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

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

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

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

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

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

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

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

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

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

What Do Genealogists Do?

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

Job Description

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

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

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

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

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

Here you go, courtesy of Jessica:

About You

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

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

Even better if:

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

What you’ll be doing at Legacy Tree:

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

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

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

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

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

Contractor or Employee

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

This may or may not be good news for you.

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

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

Compensation

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

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

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

Professional services are not and should not be free.

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

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

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

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

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

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

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

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

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

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

Training and Certification

Now for the good news and the bad news.

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

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

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

Genealogy Training

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

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

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

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

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

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

Genetic Genealogy Training

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

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

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

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

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

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

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

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

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

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

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

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

Apprenticeship

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

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

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

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

Networking Opportunity

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

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

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

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

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

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DNA: In Search Of…Your Grandparents

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Are you searching for an unknown relative or trying to unravel and understand unexpected results? Maybe you discovered that one or both of your parents is not your biological parent. Maybe one of your siblings might be a half-sibling instead. Or maybe you suddenly have an unexpected match that looks to be an unknown close relative, possibly a half-sibling. Perhaps there’s a close match you can’t place.

Or, are you searching for the identity of your grandparent or grandparents? If you’re searching for your parent or parents, often identifying your grandparents is a necessary step to narrow the parent-candidates.

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

Identifying a Grandparent

I saved this “grandparents” article for later in the series because you will need the tools and techniques I’ve introduced in the earlier articles. Identifying grandparents is often the most challenging of any of the relationships we’ve covered so far. In part because each of those four individuals occupies a different place in your tree, meaning their X, Y-DNA and mitochondrial DNA is carried by different, and not all, descendants. This means we sometimes have to utilize different tools and techniques.

If you’re trying to identify any of your four grandparents, females are sometimes more challenging than males.

Why?

Women don’t have a Y chromosome to test. This can be a double handicap. Female testers can’t test a Y chromosome, and maternal ancestors don’t have a Y chromosome to match.

Of course, every circumstance differs. You may not have a male to test for paternal lines either.

The maternal grandfather can be uniquely challenging, because two types of DNA, Y-DNA and mitochondrial DNA matching are immediately eliminated for all testers.

While I’ve focused on the maternal grandfather in this example, these techniques can be utilized for all four grandparents as well as for parents. At the end, I’ll review other grandparent relationships and additional tools you might be able to utilize for each one.

In addition to autosomal DNA, we can also utilize mitochondrial DNA, Y-DNA and sometimes X DNA in certain situations.

Testing, Tests and Vendors

As you recall, only men have a Y chromosome (blue arrow), so only genetic males can take a Y-DNA test. Men pass their Y chromosome from father to son in each generation. Daughters don’t receive a Y chromosome.

Everyone has their mother’s mitochondrial DNA (pink arrow.) Women pass their mitochondrial DNA to both sexes of their children, but only females pass it on. In the current generation, represented by the son and daughter, above, the mother’s yellow heart-shaped mitochondrial DNA is inherited by both sexes of her children. In the current generation, males and females can both test for their mother’s mitochondrial DNA.

Of course, everyone has autosomal DNA, inherited from all of their ancestral lines through at least the 5th or 6th generation, and often further back in time. Autosomal DNA is divided in half in each generation, as children inherit half of each parents’ autosomal DNA (with the exception of the X chromosome, which males only inherit from their mother.)

The four major vendors, Ancestry, 23andMe, FamilyTreeDNA and MyHeritage sell autosomal DNA tests, but only FamilyTreeDNA sells Y-DNA and mitochondrial DNA tests.

Only 23andMe and FamilyTreeDNA report X matching.

All vendors except Ancestry provide segment location information along with a chromosome browser.

You can read about the vendor’s strengths and weaknesses in the third article, here.

Ordering Y and Mitochondrial DNA Tests

If you’re seeking the identities of grandparents, the children and parents, above, can test for the following types of DNA in addition to autosomal:

Person in Pedigree Y-DNA Mitochondrial
Son His father’s blue star His mother’s pink heart
Daughter None Her mother’s pink heart
Father His father’s blue star His mother’s gold heart
Mother None Her mother’s pink heart

Note that none of the people shown above in the direct pedigree line carry the Y-DNA of the green maternal grandfather. However, if the mother has a full sibling, the green “Male Child,” he will carry the Y-DNA of the maternal grandfather. Just be sure the mother and her brother are full siblings, because otherwise, the brother’s Y-DNA may not have been inherited from your mother’s father. I wrote about full vs half sibling determination, here.

Let’s view this from a slightly different perspective. For each grandparent in the tree, which of the two testers, son or daughter, if either, carry that ancestor’s DNA of the types listed in the columns.

Ancestor in Tree Y-DNA Mitochondrial DNA Autosomal DNA X DNA
Paternal Grandfather Son Neither Son, daughter Neither
Paternal Grandmother Has no Y chromosome None (father has it, doesn’t pass it on to son or daughter) Son, daughter Daughter (son does not receive father’s X chromosome)
Maternal Grandfather Neither Neither Son, daughter Son, daughter (potentially)
Maternal Grandmother Has no Y chromosome Son, daughter Son, daughter Son, daughter (potentially)

Obtaining the Y-DNA and mitochondrial DNA of those grandparents from their descendants will provide hints and may be instrumental in identifying the grandparent.

FamilyTreeDNA

You’ll need to order Y-DNA (males only) and mitochondrial DNA tests separately from autosomal DNA tests. They are three completely different tests.

At FamilyTreeDNA, the autosomal DNA test is called Family Finder to differentiate it from their Y-DNA and mitochondrial DNA tests.

Their autosomal test is called Family Finder whether you order a test from FamilyTreeDNA, or upload your results to their site from another vendor (instructions here.)

I recommend ordering the Big Y-700 Y-DNA test if possible, and if not, the highest resolution Y-DNA test you can afford. The Big Y-700 is the most refined Y-DNA test available, includes multiple tools and places Big Y-700 testers on the Time Tree through the Discover tool, providing relatively precise estimates of when those men shared a common ancestor. If you’ve already purchased a lower-precision Y-DNA test at FamilyTreeDNA, you can easily upgrade.

I wrote about using the Discover tool here. The recently added Group Time Tree draws a genetic Y-DNA tree of Big-Y testers in common projects, showing earliest known ancestors and the date of the most recent common ancestor.

You need to make sure your Family Finder, mitochondrial DNA and Y-DNA (if you’re a male) tests are ordered from the same account at FamilyTreeDNA.

You want all 3 of your tests on the same account (called a kit number) so that you can use the advanced search features that display people who match you on combinations of multiple kinds of tests. For example, if you’re a male, do your Y-DNA matches also match you on the autosomal Family Finder test, and if so, how closely? Advanced matching also provides X matching tools.

X DNA is included in autosomal tests. X DNA has a distinct matching pattern for males and females which makes it uniquely useful for genealogy. I wrote about X DNA matching here.

If you upload your autosomal results to FamilyTreeDNA from another company, you’re only uploading a raw DNA file, not the DNA itself, so FamilyTreeDNA will need to send you a swab kit to test your Y-DNA and mitochondrial DNA. If you upload your autosomal DNA, simply sign in to your kit, purchase the Y-DNA and/or mitochondrial DNA tests and they will send you a swab kit.

If you test directly at FamilyTreeDNA, you can add any test easily by simply signing in and placing an order. They will use your archived DNA from your swab sample, as long as there’s enough left and it’s of sufficient quality.

Fish In All Ponds

The first important thing to do in your grandparent search is to be sure you’re fishing in all ponds. In other words, be sure you’ve tested at all 4 vendors, or uploaded files to FamilyTreeDNA and MyHeritage.

When you upload files to those vendors, be sure to purchase the unlock for their advanced tools, because you’re going to utilize everything possible.

If you have relatively close matches at other vendors, ask if they will upload their files too. The upload is free. Not only will they receive additional matches, and another set of ethnicity results, their results will help you by associating your matches with specific sides of your family.

Why Order Multiple Tests Now Instead of Waiting?

I encourage testers to order their tests at the beginning of their journey, not one at a time. Each new test from a vendor takes about 6-8 weeks from the time you initially order – they send the test, you swab or spit, return it, and they process your DNA. Of course, uploading takes far less time.

If you’re adding elapsed time, two autosomal tests (Ancestry and 23andMe), two uploads (FamilyTreeDNA and MyHeritage,) a Y-DNA and a mitochondrial DNA test, if all purchased serially, one after the other, means you’ll be waiting about 6-8 months.

Do you want to wait 6-8 months? Can you afford to?

Part of that answer has to do with what, exactly, you’re seeking.

A Name or Information?

Are you seeking the name of a person, or are you seeking information about that person? With grandparents, you may be hoping to meet them, and time may be of the essence. Time delayed may not be able to be recovered or regained.

Most people don’t just want to put a name to the person they are seeking – they want to learn about them. You will have different matches at each company. Even after you identify the person you seek, the people you match at each company may have information about them, their photos, know about their life, family, and their ancestors. They may be able and willing to facilitate an introduction if that’s what you seek.

One cousin that I assisted discovered that his father had died just 6 weeks before he made the connection. He was heartsick.

Having data from all vendors simultaneously will allow you to compile that data and work with it together as well as separately. Using your “best” matches at each company, augmented by both Y-DNA and mitochondrial DNA can make MUCH shorter work of this search.

Your Y-DNA, if you’re a male will give you insights into your surname line, and the Big-Y test now comes with estimates of how far in the past you share a common ancestor with other men that have taken the Big-Y test. This can be a HUGE boon to a male trying to figure out his surname line.

Y-DNA and mitochondrial DNA, respectively, will eliminate many people from being your mother or father, or your direct paternal or direct maternal line ancestor. Both provide insights into which population and where that population originated as well. In other words, it provides you lineage-specific information not available elsewhere.

Your Y-DNA and mitochondrial DNA can also provide critically important information about whether that direct line ancestor belonged to an endogamous population, and where they came from.

Strategies

You may be tempted to think that you only need to test at one vendor, or at the vendor with the largest database, but that’s not necessarily true.

Here’s a table of my closest matches at the 4 vendors.

Vendor Closest Maternal Closest Paternal Comments
Ancestry 1C, 1C1R Half 1C, 2C I recognized both of the maternal and neither of the paternal.
23andMe 2C, 2C 1C1R, half-gr-niece Recognized both maternal, one paternal
MyHeritage Mother uploaded, 1C Half-niece, half 1C Recognized both maternal, one paternal
FamilyTreeDNA Mother tested, 1C1R Parent/child, half-gr-niece Recognized all 4

To be clear, I tested my mother at FamilyTreeDNA before she passed away, but if I was an adoptee searching for my mother, that’s the first database she would be in. As her family, we were able to order the Family Finder test from her archived DNA after she had passed away. I then uploaded her DNA file to MyHeritage, but she’ll never be at either 23andMe or Ancestry because they don’t accept uploads and she clearly can’t test.

Additionally, being able to identify maternal matches by viewing shared matches with my mother separates out close matches from my paternal side.

Let’s put this another way, I stand a MUCH BETTER chance of unraveling this mystery with the combined closest matches of all 4 databases instead of the top ones from just one database.

I’m providing analysis methodologies for working with results from all of the vendors together, in case your answer is not immediately obvious. Taking multiple tests facilitates using all of these tools immediately, not months later. Solving the puzzle sooner means you may not miss valuable connection opportunities.

You may also discover that the door slams shut with some people, but another match may be unbelievably helpful. Don’t unnecessarily limit your possibilities.

Here’s the testing and upload strategy I recommend.

What When Ancestry 23andMe MyHeritage FamilyTreeDNA GEDmatch
Order autosomal test Initially Yes Yes Upload Upload Upload
Order Big-Y DNA test if male Initially Yes
Order mitochondrial DNA test Initially Yes
Upload free autosomal file From Ancestry or 23andMe Yes Yes Yes
Unlock Advanced Tools When upload file $29 $19 $9.95 month
Includes X Matching No Yes No Yes Yes
Chromosome Browser, segment location information No Yes Yes Yes Yes

When you upload a DNA file to a vendor site, only upload one file per site, per tester. Otherwise, multiple tests simply glom up everyone’s match list with multiple matches to the same person and can be very confusing.

  • One person took an autosomal test at a company that accepts uploads, forgot about it, uploaded a file from another vendor later, and immediately thought she had found her parent. She had not. She “found” herself.
  • Another person though she had found two sisters, but one person had uploaded their own file from two different vendors.

Multiple vendor sites reveal multiple close matches to different people which increase your opportunity to discover INFORMATION about your family, not just the identity of the person.

Match Ranges

Given that we are searching for an unknown maternal grandfather, your mother may not have had any (known) full siblings. The “best” match would be to a full or half siblings to your parents, or their descendants, depending on how old your grandparents would be.

Let’s take the “worst case” scenario, meaning there are no full siblings AND there are many possible generations between you and the people you may match.

Now, let’s look at DNAPainter’s Shared cM tool.

You’re going to be looking for someone who is either your mother’s half sibling on her father’s side, or who is a full sibling.

If your mother is adopted, it’s possible that she has or had full siblings. If your mother was born circa 1920, it’s likely that you will be matching the next generation, or two, or three.

However, if your mother was born later, you could be matching her siblings directly.

I’m going to assume half siblings for this example, because they are more difficult than full siblings.

Full sibling relationships for your mother’s siblings are listed at right. Your full aunt or uncle at top, then their descendant generations below.

At left, in red, are the half-sibling relationships and the matching amounts.

You can see that if you’re dealing with half 1C3R (half first cousin three times removed,) you may not match.

Therefore, in order to isolate matches, it’s imperative to test every relevant relative possible.

Who’s Relevant for DNA Testing?

Who is relevant to test If you’re attempting to identify your maternal grandfather?

The goal is to be able to assign matches to the most refined ancestor possible. In other words, if you can assign someone to either your grandmother’s line, or your grandfather’s line, that’s better than assigning the person to your grandparents jointly.

Always utilize the tests of the people furthest up the tree, meaning the oldest generations. Their DNA is less-diluted, meaning it has been divided fewer times. Think about who is living and might be willing to test.

You need to be able to divide your matches between your parents, and then between your grandparents on your mother’s side.

  • Test your parents, of course, and any of their known siblings, half or full.
  • If those siblings have passed away, test as many of their children as you can.
  • If any of your grandparents are living, test them
  • If BOTH of your grandparents on the same side aren’t available to test, test any, preferably all, living aunts or uncles.
  • If your maternal grandmother had siblings, test them or their descendants if they are deceased.
  • If your parents are deceased, test your aunts, uncles, full siblings and half-siblings on your mother’s side. (Personally, I’d test all half-siblings, not just maternal.)
  • Half-siblings are particularly valuable because there is no question which “side” your shared DNA came from. They will match people you don’t because they received part of your parent’s DNA that you did not.

Furthermore, shared matches to half-siblings unquestionably identify which parent those matches are through.

Essentially, you’re trying to account for all matches that can be assigned to your grandparents whose identities you know – leaving only people who descend from your unknown maternal grandfather.

Testing your own descendants will not aid your quest. There is no need to test them for this purpose, given that they received half of your DNA.

I wrote about why testing close relatives is important in the article Superpower: Your Aunts’ and Uncles’ DNA is Your DNA Too – Maximize Those Matches!

Create or Upload a Tree

Three of the four major vendors, plus GEDMatch, support and utilize family trees.

You’ll want to either upload or create a tree at each of the vendor sites.

You can either upload a GEDCOM file from your home computer genealogy software, or you can create a tree at one of the vendors, download it, and upload to the others. I described that process at Ancestry, here.

Goal

Your goal is to work with your highest matches first to determine how they are related to you, thereby eliminating matches to known lineages.

Assuming you’re only searching for the identity of one grandparent, it’s beneficial to have done enough of your genealogy on your three known grandparents to be able to assign matches from those lines to those sides.

Step 1 is to check each vendor for close matches that might fall into that category.

The Top 15 at Each Vendor

Your closest several autosomal matches are the most important and insightful. I begin with the top 15 autosomal results at each vendor, initially, which provides me with the best chance of meaningful close relationship discoveries.

Create a Spreadsheet or Chart

I hate to use that S word (spreadsheet), because I don’t want non-technical people to be discouraged. So, I’m going to show you how I set up a spreadsheet and you can simply create a chart or even draw this out on paper if you wish.

I’ve color-coded columns for each of my 4 grandparents. The green column is the target Maternal Grandfather whose identity I’m seeking.

I match our first example; Erik, at 417 cM. Based on various pieces of information, taken together, I’ve determined that I’m Erik’s half 1C1R. His 8 great-grandparent surnames, or the ones he has provided, indicate that I’m related to Eric on my paternal grandfather’s line.

You’ll want to record your closest matches in this fashion.

Let’s look at how to find this information and work with the tools at the individual vendors.

23andMe

Let’s start at 23andMe, because they create a potential genetic tree for you, which may or may not be accurate.

I have two separate tests at 23andMe. One is a V3 and one is a V4 test. I keep one in its pristine state, and I work with the second one. You’ll see two of “me” in the tree, and that’s why.

23andMe makes it easy to see estimated relationships, although they are not always correct. Generally, they are close, and they can be quite valuable.

Click on any image to enlarge

The maternal and paternal “sides” may not be positioned where genealogists are used to seeing them. Remember, 23andMe has no genealogy trees, so they are attempting to construct a genetic tree based on how people are related to you and to each other, with no prior knowledge. They do sometimes have issues with half-relationships, so I’d encourage you to use this tree to isolate people to the three grandparents you know.

In my case, I was able to determine the maternal and paternal sides easily based on known cousins. This is the perfect example of why it’s important to test known relatives from both sides of your family.

My paternal side, at right, in blue, was easy because I recognized my half-sister’s family, and because of known cousins who I recognized from having tested elsewhere. I’ve worked with them for years. The blue stars show people I could identify, mostly second cousins.

My maternal side is at left, in red. Normally, for genealogists, the maternal side is at right, and the paternal at left, so don’t make assumptions, and don’t let this positioning throw you.

I’m pretending I don’t know who my maternal grandfather is. I was able to identify my maternal grandmother’s side based on a known second cousin.

That leaves my target – my maternal grandfather’s line.

All of the matches to the left of the red circle would, by process of elimination, be on my maternal grandfather’s side.

The next step would be to figure out how the 5 people descending from my maternal grandfather’s line are related to each other – through which of their ancestors.

On the DNA Relatives match list, here’s what needs to be checked:

  • Do your matches share surnames with you or your ancestors?
  • Do they show surnames in common with each other?
  • Is there a common location?
  • Birth year which helps you understand their potential generation.
  • Did they list their grandparents’ birthplaces?
  • Did they provide a family tree link?
  • Do they also match each other using the Relatives in Common feature?
  • Do they triangulate, indicated by “DNA Overlap” in Relatives in Common?
  • Who else is on the Relatives in Common list, and what do they have in common with each other?
  • Looking at your Ancestry Composition compared with theirs, what are your shared populations, and are they relevant? If you are both 100% European, then shared populations aren’t useful, but if both people share the same minority ancestry, especially on the same segments, it may indeed be relevant – especially if it can’t be accounted for on the known sides of the family.

Reach out to these people and see what they know about their genealogy, if they have tested elsewhere, and if they have a genealogy tree someplace that you can view.

If they can tell you their grandparents’ names, birth and death dates and locations, you can check public sources like WikiTree, FamilySearch and Geni, or build trees for them. You can also use Newspaper resources, like Newspapers.com, NewspaperArchive and the newspapers at MyHeritage.

I added the top 15 23andMe matches into the spreadsheet I created.

You’ll notice that not many people at 23andMe enter surnames. However, if you can identify individuals from your 3 known lines, you can piggyback the rest by using Relatives in Common in conjunction with the genetic tree placement.

Be sure to check all the people that are connected to the target line in your genetic tree.

You’ll want to harvest your DNA segments to paint at DNAPainter if you don’t solve this mystery with initial reviews at each vendor.

Ancestry

Let’s move to Ancestry next.

At Ancestry, you’ll want to start with your closest matches on your match list.

Ancestry classifies “Close Matches” as anyone 200 cM or greater, which probably won’t reach as far down as the matches we’ll want to include.

Some of the categories in the Shared cM Chart from DNAPainter, above, don’t work based on ages, so I’ve eliminated those. I also know, for example, that someone who could fall in the grandparent/grandchild category (blue star,) in my case, does not, so must be a different relationship.

Second cousins, who share great-grandparents, can be expected to share about 229 cM of DNA on average, or between 41 and 592 cM. First cousins share 866 cM, and half first cousins share 449 cM on average.

I have 13 close matches (over 200 cM), but I’m including my top 15 at each vendor, so I added two more. You can always go back and add more matches if necessary. Just keep in mind that the smaller the match, the greater the probability that it came from increasingly distant generations before your grandparents. Your sweet spot to identify grandparents is between 1C and 2C.

I need to divide my close matches into 4 groups, each one equating to a grandparent. Record this on your spreadsheet.

You can group your matches at Ancestry using colored dots, which means you can sort by those groups.

You can also select a “side” for a match by clicking on “Yes” under the question, “Do you recognize them?”

Initially, you want to determine if this person is related to you on your mother’s or father side, and hopefully, through which grandparent.

Recently, Ancestry added a feature called SideView which allows testers to indicate, based on ethnicity, which side is “parent 1” and which side is “parent 2.” I wrote about that, here.

Make your selection, assuming you can tell which “side” of you descends from which parent based on ethnicity and/or shared matches. How you label “parent 1,” meaning either maternal or paternal, determines how Ancestry assigns your matches, when possible.

Using these tools, which may not be completely accurate, plus shared matches with people you can identify, divide your matches among your three known grandparents, meaning that the people you cannot assign will be placed in the fourth “unknown” column.

On my spreadsheet, I assign all of my closest matches to one of my grandparents. Michael is my first cousin (1C) and we share both maternal grandparents, so he’s not helpful in the division because he can’t be assigned to only one grandparent.

The green maternal grandfather is who I’m attempting to identify.

There are 4 people, highlighted in yellow, who don’t fall into the other three grandparent lines, so they get added to the green column and will be my focus.

I would be inclined to continue adding matches using a process known as the Leeds Method, until I had several people in each category. Looking back at the DNAPainter cM chart, at this point, we don’t have anyone below 200 cM and the matches we need might be below that threshold. The more matches you have to work with, the better.

At Ancestry, you cannot download your matches into a spreadsheet, nor can you work with other clustering tools such as Genetic Affairs, so you’ll have to build out your spreadsheet manually.

Check for the same types of information that I reviewed at 23andMe:

  • Review trees, if your matches have them, minimally recording the surnames of their 8 great-grandparents.
  • Review shared matches, looking for common names in the trees in recent generations.
  • View shared matches with people with whom you have a “Common Ancestor” indication, which means a ThruLine. You won’t have Thrulines with your target grandparent, of course, but Thrulines will allow you to place the match in one of the other columns. I wrote about ThruLines here, here and here.
  • ThruLines sometimes suggests ancestors based on other people’s trees, so be EXCEEDINGLY careful with potential ancestor suggestions. That’s not to say you should discount those suggestions. Just treat them as tree hints that may have been copy/pasted hundreds of times, because that’s what they are.

I make notes on each match so I can easily see the connection by scanning without opening the match.

Now, I have a total of 30 entries on my spreadsheet, 15 from 23and Me and 15 from Ancestry.

Why Not Use Autosclusters?

Even with vendors who allow or provide cluster tools, I don’t use an automated autocluster tool at this point. Autocluster tools often omit your closest matches because your closest matches would be in nearly half of all your clusters, which isn’t exactly informative. However, for this purpose, those are the very matches we need to evaluate.

After identifying groups of people that represent the missing grandparent, using our spreadsheet methodology, autoclusters could be useful to identify common surnames and even to compare the trees of our matches using AutoTree, AutoPedigree and AutoKinship. AutoClusters cannot be utilized at Ancestry, but is available through MyHeritage and at GEDmatch, or through Genetic Affairs for 23andMe and FamilyTreeDNA.

Next, let’s move to FamilyTreeDNA.

FamilyTreeDNA

FamilyTreeDNA is the only vendor that provides Family Matching, also known as “bucketing.” FamilyTreeDNA assigns your matches to either a paternal or maternal bucket, or both, based on triangulated matches with someone you’ve linked to a profile in your tree.

The key to Family Matching is to link known Family Finder matches to their profile cards in your tree.

Clicking on the Family Tree link at the top of your personal page allows you to link your matches to the profile cards of your matches.

FamilyTreeDNA utilizes these linked matches to assign those people, and matches who match you and those people, both, on at least one common segment, to the maternal or paternal tabs on your match list.

Always link as many known people as possible (red stars) which will result in more matches being bucketed and assigned to parents’ sides for you, even if neither parent is available to test.

I wrote about Triangulation in Action at FamilyTreeDNA, here.

You can see at the top of my match list that I have a total of 8000 matches of which 3422 are paternal, 1517 are maternal and 3 match on both sides. Full siblings, their (and my) children and their descendants will always match on both sides. People with endogamy across both parents may have several matches on both sides.

If your relevant parent has tested, always work from their test.

Because we are searching for the maternal grandfather, in this case, we can ignore all tests that are bucketed as paternal matches.

Given that we are searching for my maternal grandfather, I probably have not been able to link as many maternal matches, other than possibly ones from my maternal grandmother. This means that the maternal grandfather’s matches are not bucketed because there are no identified matches to link on that side of my tree.

If you sort by maternal and paternal tabs, you’ll miss people who aren’t bucketed, meaning they have no maternal or paternal icon, so I recommend simply scanning down the list and processing maternal matches and non-bucketed matches.

By being able to confidently ignore paternally bucketed matches and only processing maternal and non-assigned matches, this is equivalent to processing the first 48 total matches. If I were to only look at the first 15 matches, 12 were paternal and only 3 are maternal.

Using bucketing at FamilyTreeDNA is very efficient and saves a lot of work.

Omitting paternal matches also means we are including smaller matches which could potentially be from common ancestors further back in the tree. Or, they could be younger testers. Or simply smaller by the randomness of recombination.

FamilyTreeDNA is a goldmine, with 16 of 20 maternal matches being from the unknown maternal grandfather.

Next, let’s see what’s waiting at MyHeritage.

MyHeritage

MyHeritage is particularly useful if your lineage happens to be from Europe. Of course, if you’re searching for an unknown person, you probably have no idea where they or their ancestors are from. Two of my best matches first appeared at MyHeritage.

Of course, your matches with people who descend from your unknown maternal grandfather won’t have any Theories of Family Relativity, as that tool is based on BOTH a DNA match plus a tree or document match. However, Theories is wonderful to group your matches to your other three grandparents.

MyHeritage provides a great deal of information for each match, including common surnames with your tree. If you recognize the surnames (and shared matches) as paternal or maternal, then you can assign the match. However, the matches you’re most interested in are the highest matches without any surnames in common with you – which likely point to the missing maternal grandfather.

However, those people may, and probably do, have surnames in common with each other.

Of the matches who aren’t attributed to the other three grandparents, the name Ferverda arises again and again. So does Miller, which suggests the grandparent or great-grandparent couple may well be Ferverda/Miller.

Let’s continue working through the process with our spreadsheet and see what we can discover about those surnames.

Our 60 Results

Of the 60 total results, 15 from each vendor, a total of 24 cannot be assigned to other columns through bucketing or shared matches, so are associated with the maternal grandfather. Of course, Michael who descends from both of my maternal grandparents won’t be helpful initially.

Cheryl, Donald and Michael are duplicates at different vendors, but the rest are not.

Of the relevant matches, the majority, 12 are from FamilyTreeDNA, four each are from Ancestry and MyHeritage, and three are from 23andMe.

Of the names provided in the surname fields of matches, in matches’ trees in the first few generations, and the testers’ surnames, Ferverda is repeated 12 times, for 50% of the time. Miller is repeated 9 times, so it’s likely that either of those are the missing grandfather’s surname. Of course, if we had Y-DNA, we’d know the answer to that immediately.

Comparing trees of my matches, we find John Ferverda as the common ancestor between two different matches. John is the son of Hiram Ferverda and Eva Miller who are found in several trees.

That’s a great hint. But is this the breakthrough I need?

What’s Next?

The next step is to look for connections between the maternal grandmother, Edith Lore, who is known in our example, and a Ferverda male. He is probably one of the sons of Hiram Ferverda and Eva Miller. Do they lived in the same area? In close proximity? Do they attend the same church or school? Are they neighbors or live close to the family or some of their relatives? Does she have connections with Ferverda family members? We are narrowing in.

Some of Hiram and Eva’s sons might be able to be eliminated based on age or other factors, or at least be less likely candidates. Any of their children who had moved out of state when the child was conceived would be less likely candidates. Age would be a factor, as would opportunity.

Target testing of the Ferverda sons’ children, or the descendants of their children would (probably) be able to pinpoint which of their sons is more closely related to me (or my mother) than the rest.

In our case, indeed, John Ferverda is the son we are searching for and his descendant, Michael is the highest match on the list. Cheryl and Donald descend from John’s brother, which eliminates him as a candidate. Another tester descends from a third Ferverda son, which eliminates that son as well.

Michael, my actual first cousin with a 755 cM match at one vendor, and 822 cM at a second vendor, is shown by the MyHeritage cM Explainer with an 88% probability that he is my first cousin.

However, when I’m trying to identify the maternal grandfather, which is half of that couple, I need to focus one generation further back in time to eliminate other candidates.

The second and third closest matches are both Donald at 395 cM and Cheryl at 467 cM who also share the same Ferverda/Miller lineage and are the children of my maternal grandfather’s brother.

On the spreadsheet, I need to look at the trees of people who have both Ferverda and Miller, which brought me to both Cheryl and Donald, then Michael, which allowed me to identify John Ferverda, unquestionably, as my grandfather based on the cM match amounts.

Cheryl and Donald, who are confirmed full siblings, and my mother either have to be first cousins, or half siblings. Their match with mother is NOT in the half-sibling range for one sibling, and on the lower edge with the other. Mother also matches Michael as a nephew, not more distantly as she would if he were a first cousin once removed (1C1R) instead of a nephew.

Evaluating these matches combined confirms that my maternal grandfather is indeed John Ferverda.

What About X DNA?

The X chromosome has a unique inheritance path which is sometimes helpful in this circumstance, especially to males.

Women inherit an X chromosome from both parents, but males inherit an X chromosome from ONLY their mother. A male inherits a Y chromosome from his father which is what makes him male. Women inherit two X chromosomes, one from each parent, and no Y, which is what makes them female.

Therefore, if you are a male and are struggling with which side of your tree matches are associated with, the X chromosome may be of help.

Your mother passed her X chromosome to you, which could be:

  • Her entire maternal X, meaning your maternal grandmother’s X chromosome
  • Her entire paternal X, meaning your maternal grandfather’s X chromosome (which descends from his mother)
  • Some combination of your maternal grandmother and maternal grandfather’s chromosomes

One thing we know positively is that a male’s X matches are ALWAYS from their maternal side only, so that should help when dividing a male’s matches maternally or paternally. Note – be aware of potential pedigree collapse, endogamy and identical-by-chance matches if it looks like a male has a X match on his father’s side.

Unfortunately, the X chromosome cannot assist females in the same way, because females inherit an X from both parents. Therefore, they can match people in the same was as a male, but also in additional ways.

  • Females will match their paternal grandmother on her entire X chromosome, and will match one or both of their maternal grandparents on the X chromosome.
  • Females will NEVER match their paternal grandfather’s X chromosome because their father did not inherit an X chromosome from his father.
  • Males will match one or both of their maternal grandparents on their X chromosome.
  • Males will NEVER match their paternal grandparents, because males do not receive an X chromosome from their father.

The usefulness of X DNA matching depends on the inheritance path of both the tester AND their match.

When Can Y-DNA or Mitochondrial DNA Help with Grandparent Identification?

If you recall, I selected the maternal grandfather as the person to seek because no tester carries either the Y-DNA or mitochondrial DNA of their maternal grandfather. In other words, this was the most difficult identification, meaning that any of the other three grandparents would be, or at least could be, easier with the benefit of Y-DNA and/or mitochondrial DNA testing.

In addition to matching, both Y-DNA and mitochondrial DNA will provide testers with location origins, both continental and often much more specific locations based on where other testers and matches are from.

Y-DNA often provides a surname.

Let’s see how these tests, matches and results can assist us.

  • Paternal grandfather – If I was a male descended from John Ferverda paternally, I could have tested both my autosomal DNA PLUS my Y-DNA, which would have immediately revealed the Ferverda surname via Y-DNA. Two Ferverda men are shown in the Ferverda surname DNA project, above.

That revelation would have confirmed the Ferverda surname when combined with the high frequency of Ferverda found among autosomal matches on the spreadsheet.

  • Maternal grandmother – If we were searching for a maternal grandmother, both the male and female sibling testers (as shown in the pedigree chart) would have her mitochondrial DNA which could provide matches to relevant descendants. Mitochondrial DNA at both FamilyTreeDNA and 23andMe could also eliminate anyone who does not match on a common haplogroup, when comparing 23andMe results to 23andMe results, and FamilyTreeDNA to FamilyTreeDNA results at the same level.

At 23andMe, only base level haplogroups are provided, but they are enough to rule out a direct matrilineal line ancestor.

At FamilyTreeDNA, the earlier HVR1 and HVR2 tests provide base level haplogroups, while full sequence testing provides granular, specific haplogroups. Full sequence is the recommended testing level.

  • Paternal grandmother – If we were searching for a paternal grandmother, testers would, of course, need either their father to test his mitochondrial DNA, or for one of his siblings to test which could be used in the same way as described for maternal grandmother matching.

Summary

Successfully identifying a grandparent is dependent on many factors. Before you make that identification, it’s very difficult to know which are more or less important.

For example, if the grandparent is from a part of the world with few testers, you will have far fewer matches, potentially, than other lines from more highly tested regions. In my case, two of my four grandparents’ families, including Ferverda, immigrated in the 1850s, so they had fewer matches than families that have been producing large families in the US for generations.

Endogamy may be a factor.

Family size in past and current generations may be a factor.

Simple luck may be a factor.

Therefore, it’s always wise to test your DNA, and that of your parents and close relatives if possible, and upload to all of the autosomal databases. Then construct an analysis plan based on:

  • How you descend from the grandparent in question, meaning do you carry their X DNA, Y-DNA or mitochondrial DNA.
  • Who else is available to test their autosomal DNA to assist with shared matches and the process of elimination.
  • Who else is available to test for Y-DNA and/or mitochondrial DNA of the ancestor in question.

If you don’t find the answer initially, schedule a revisit of your matches periodically and update your spreadsheet. Sometimes DNA and genealogy is a waiting same.

Just remember, luck always favors the prepared!

Resources

You may find the following resource articles beneficial in addition to the links provided throughout this article.

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X Chromosome Master Class

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

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

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

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

Let’s get started!

Who Uses the X Chromosome?

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

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

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

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

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

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

What is X-DNA?

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

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

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

Everyone inherits one copy of chromosome 23 from each parent.

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

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

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

Everyone has both X-DNA AND mitochondrial DNA.

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

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

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

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

The Unique X Chromosome

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

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

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

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

My X Chromosome Family Tree

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

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

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

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

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

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

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

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

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

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

Using DNA Painter as an X Tool

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

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

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

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

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

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

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

Click on any image to enlarge

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

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

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

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

Does Size Matter?

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

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

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

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

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

X Chromosome Differences are Important!

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

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

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

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

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

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

How Do I Interpret an X Match?

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

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

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

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

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

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

Critical Take-Away Messages

Here are the critical take-away messages:

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

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

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

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

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

Said Another Way

Let’s look at this another way.

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

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

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

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

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

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

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

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

Bottom Line

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

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

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

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

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

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

The Best Part!

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

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

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

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

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

Using X DNA to Solve a Mystery

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

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

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

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

I added blockers on her chart and mine too.

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

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

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

My X Chromosome at DNA Painter

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

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

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

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

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

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

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

X-DNA Advanced Matches at FamilyTreeDNA

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

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

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

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

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

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

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

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

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Relatives at RootsTech – How to Use & Connect with DNA

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Relatives at RootsTech is back and I’m so very glad to see it.

Let me show you how to use this wonderful tool, including tips for how to get even more out of the experience.

It’s important to start now to accumulate your cousins, because there’s a display limit of 300 in each category, so you’ll want to begin recording your findings so that as more people sign up and are added to your list, you don’t “lose” the earlier relatives.

Let’s start with my link. Click here.

You’ll be prompted to sign in to your FamilySearch account, or create one. If you don’t have an account, create one now.

Right now, the number of participants is doubling every few days.

Let’s take a look at how Relatives at RootsTech works and how it can benefit you.

Surnames

At first glance, the surname tool doesn’t look terribly exciting, but there’s a hidden gem, especially for newer genealogists.

I entered my surname and one other, knowing there is probably no common locations other than the US. Kvochick is very rare and unique.

The results show two interesting things. First, the genesis of the surname, and second, the total number of people in the FamilySearch tree in both of the common locations for both surnames.

Be sure to try variant spellings too.

After you sign in, you’ll be asked to update your profile which is how you join in on the fun. If you signed up for Relatives at RootsTech last year, that doesn’t count for this year. You need to opt-in for this year’s festivities.

RootsTech Relatives

After you sign in, you’ll see how many of your relatives have joined.

Of the 60,461 total who have joined, according to the FamilySearch tree, I’m related to about 15% of them. That sure gives new perspective to how many people we’re related to. And just think if those brick walls didn’t exist. We’d be related to just about everyone. Far enough back, we’re all related, literally.

Your Relatives at RootsTech are displayed in three ways.

By location, ancestor or family line.

Relatives by Location

Your first view will be by all locations (including people who did not select a location,) but displayed in closest to most distant relationship order. For me, that’s the most interesting part.

These people, my closest relatives, are the people most likely to have critical pieces of information that I don’t have or know about. Like family stories, or photos, for example.

I know one of these people, but not the rest. I’m dying to know who they are and how we are related.

For me, the map itself isn’t terribly useful, but it would be if some members of your family were from distinct locations.

Not everyone opts in to have their location displayed. The “173” in the center is the people who generically selected United States.

Relatives by Family Line

The Family Line display shows you the number of people by parent or grandparent. Unfortunately, you can only view 300 of your matches in each line, which is disappointing.

However, there’s a better way to view your relatives.

Relatives by Ancestor

For me, the best way to view relatives is by ancestor. This also circumvents the 300 limit to some extent, unless you have more than 300 relatives for any one ancestor.

I have two relatives who also descend from Curtis Benjamin Lore. It’s Jen and Jill again, my closest relatives.

I’m quite interested in these people, because Curtis is my great-grandfather and he was a very interesting man. I know Jen and Jill are interested in genealogy too, or they would not have signed up for RootsTech Relatives, this year, in the past few days. This is not a stale list.

I’ll be messaging them as soon as I’m finished with this article!!!

Please note that FamilySearch does not label half-relationships accurately.

Jen and Jill are my HALF second cousins twice removed, which will affect the expected amount of shared DNA. Their ancestors, Edith and Maude were half-sisters through their father, not full sisters. One of the reasons I’m so interested in communicating with Jen and Jill is because I’m not at all sure that those half-sisters knew each other existed.

Maintaining Contact

For each relative found, you can view your relationship, message them, or add them to your contact list. Be aware – your contact list “saves” this person, but it does not tell you how you’re related. That’s where either a Word document, with screen shots of how you’re related, or a spreadsheet where you can detail that information is important.

If you have messaged people in the past, those messages are still in your message box in the upper right-hand corner.

I generally provide my email address when I message relatives.

Displaying the Relationship

If you click on the “Relationship” button, you’ll see how FamilySearch believes you’re related to each match.

My relationship with an Acadian cousin, beginning with our common ancestor, is shown above. Grab a screen shot so you can remember. I drop them into a spreadsheet or Word document.

These matches are based on FamilySearch’s one world type of tree. I don’t have to tell you to be cautious because, like any tree, there are erroneous connections. This connection, at least on my side (left hand,) seems to be accurate. I don’t have Jeanne Chebrat’s second marriage to Jehan Piorier in my file, so I’ll need to check that out. Many times FamilySearch, WikiTree, Ancestry, or MyHeritage has connected documents or sources. In this case, here’s the WikiTree entry for Jeanne.

See, I’ve found something interesting already.

Search for People

On the toolbar, if you click on the right arrow, you’ll notice there’s one more option – Search.

If you think one your cousins might be attending, either virtually or in person, you can search by surname. I entered Estes out of curiosity.

This is quite interesting, because some other poor soul is also named Roberta Estes. You KNOW I’ll be messaging her. I’m pretty sure I know who this is, because we’ve been getting mixed up for years. Unless, of course there are actually three of us interested in genealogy.

However, where this Search option really shines is if you’re looking for males who descend from a particular line as candidates for Y-DNA testing.

Bingo!

I suggest doing this name search for each surname in your tree.

The Share Button is Critically Important

Sharing is the key to encouraging people to participate.

This button on the main page is how I generated the link for you to use to see if we’re related.

There’s a “Share” button in several locations. However, you’ll want to be sure you know exactly what you’re sharing. In some cases, it will be the surname comparison information or other information that you’re viewing. 

However, on the bottom of your Relatives pages, Share will generate a message link to/through several programs or apps so people can sign in to see if they are related to you.

You can also just copy the link and send it to someone in a text message or otherwise.

If you generate a message to share, you’ll see what will be posted, so you’ll know for sure exactly what you’re sharing. I wanted to post the link for my friends on Facebook to see if we are related, and that’s exactly what was generated.

If you follow the link to see if we are related, be sure to tell me, or anyone else whose link you follow.

Next, Connect with DNA

Relatives for RootsTech is a wonderful segway into DNA testing.

Remember, with the 300-relative limit, different searches will produce different results including people that won’t be included due to the 300 limit in other searches. Be creative and search in multiple ways. Add your relatives to your spreadsheet or Word document, then record whether they’ve DNA tested, at which vendor(s) and if you match there.

There are various ways to utilize Relatives at RootsTech for DNA.

  • Y-DNA candidates for the direct paternal line for males – The Search by surname can provide you with Y-DNA testing candidates. They may already have tested their Y-DNA with FamilyTreeDNA or their autosomal DNA with at least one vendor, so just message them and ask. Tell them which databases you’re in. Viewing Relatives by Ancestor can be very useful for this same purpose, especially if you have multiple unrelated lines with the same surname.
  • Mitochondrial DNA – the Relatives by Ancestor tool is very useful for locating mitochondrial DNA testing candidates, especially since you can easily see how they are descended from your common ancestor. Mitochondrial DNA is passed from women through all females to the current generation, which can be male or female. Any of your cousins, of either sex, are candidates so long as they descend from your target ancestor through all females.
  • DNA Pedigree Chart – If you’re building your own DNA Pedigree Chart with the Y-DNA and mitochondrial DNA of each ancestral line, consider offering a DNA testing scholarship to people who carry those lines that are missing in your DNA Pedigree Chart.
  • Testing Candidates – Anyone is a good candidate for autosomal testing. No second cousin or closer has ever not matched. Ask your cousins if they have tested and tell them which DNA databases you are in. Furthermore, suggest that they upload their DNA to FamilyTreeDNA and MyHeritage for free to utilize their tools and find matches that aren’t in the other databases. GEDmatch isn’t a testing company, but is another free database where you may find people who tested at Ancestry. Unfortunately, Ancestry does not provide segment information for matching or painting, so hopefully you’ll be able to find your Ancestry matches elsewhere.
  • Databases – Be sure you’re in all of the databases (Ancestry, 23andMe, FamilyTreeDNA, MyHeritage and GEDmatch) so you can be found and you can find your relatives.
  • DNAPainter – If you’re painting your segments at DNAPainter, you can paint your matching segments from 23andMe, FamilyTreeDNA, MyHeritage or GEDmatch. Ancestry is the only vendor that does not provide matching segment information for their customers.
  • DNA Search – If your cousin has used their actual name when registering at FamilySearch, sort by ancestor, then search your DNA matches at the various vendors for that cousin’s name. The beauty of Relatives at RootsTech is that the relationship is already sorted by ancestor, so that piece of the puzzle has already been assembled for you, which is exactly the opposite of most DNA matches. Of course, this does not preclude errors or connections through multiple ancestors.

Limited Time – March 31 is the End

If I had a FamilySearch genie and could get one wish, it would be that they would leave Relatives for RootsTech up and available until the next RootsTech. I need time to work on these relationships.

However, that’s not the case, and Relatives for RootsTech ends on March 31st.

Therefore, it’s important to begin building your spreadsheet, or however you’re going to record your relatives, NOW. Check your list often so none of those precious matches will roll off of your list and become unavailable. Access to the complete relative match list, meaning no 300 limit would be my second wish from the FamilySearch genie.

To preserve the ability to communicate with your relatives, message them now or at least add them to your contact list – WITH A NOTE IN YOUR SPREADSHEET AS TO HOW YOU’RE RELATED. Otherwise, that information will not be available after March 31st.

You’ll want to use the same spreadsheet from year to year, as some of the relatives signing up this year probably did last year too.

Ready, Set, Relatives at RootsTech

Have fun. Be sure to let me know if we’re related and how!!!

____________________________________________________________

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You’re always welcome to forward articles or links to friends and share on social media.

If you haven’t already subscribed (it’s free,) you can receive an email whenever I publish by clicking the “follow” button on the main blog page, here.

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

Thank you so much.

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Chromosomes and Genealogy

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Sometimes people ask about how chromosomes relate to genealogy. Every single one of us started with that question, right?

Are chromosomes different sizes, and does that matter? What are the mystery terms, cMs and SNPs? How does all of this intersect with genealogy? Do I care?

These are all great questions, and of course, there are different ways to answer. Let’s start with some basics.

Chromosomes 1-22

First, you have two copies of each of chromosomes 1-22.

The karyogram above, a photo taken through a microscope, courtesy of the National Human Genome Research Institute, shows the chromosomes of a human male. I’ve added the numbering and labeled the X and Y chromosomes (23).

You inherit one copy of each chromosome from each of your parents. You can see the two halves of each chromosome, above. One half of each chromosome is contributed by the person’s mother, and the other half is contributed by the father.

That’s why DNA matching works, and each match can be designated as “maternal” or “paternal,” depending on how your match is related to you.

Each match will be related either maternally, paternally, or sometimes, both. Of course, that’s presuming the matches are identical by descent, and not identical by chance, but that’s a different discussion. For this article, we’re referencing valid matches with whom you share common ancestors – whether you know who they are or not.

Your 23rd chromosome is different than chromosomes 1-22.

Chromosome 23 Determines a Child’s Sex

Your 23rd chromosome is your sex-determination chromosome and is inherited differently.

You still inherit one copy of chromosome 23 from each parent.

  • Males inherit a Y chromosome from their father, which is what makes males male.
  • Males inherit an X chromosome from their mother.
  • Females inherit an X chromosome from both parents, which makes them female.
Chromosome 23 Father Contributes Mother Contributes
Male Child Y chromosome X chromosome
Female Child X chromosome X chromosome

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

The Y chromosome can be tested separately for males and follows the direct paternal line. You can read about the 4 Kinds of DNA for Genetic Genealogy, here.

The X chromosome is quite useful for genealogy due to its unique inheritance path and is included by both FamilyTreeDNA and 23andMe in matching.

Picture This

Three of the four major vendors, plus GEDmatch, provide a visual match depiction of your chromosomes using a chromosome browser:

Unfortunately, Ancestry does not provide a chromosome browser or segment location information.

Using your chromosomes as the canvas, matches to your father and mother are shown using the chromosome browser at FamilyTreeDNA, below.

You can see that a tester matches both parents on the entire covered region of all of their chromosomes. The beginning and the end tips of each chromosome sometimes aren’t covered, and neither are some other regions that are very SNP-location-poor. Omitted regions are shown by hashes. Regions that are light grey, but not hashed, are covered, but the match’s test didn’t produce results in that region.

This is why you may have a slightly different size match with one parent versus the other, especially if they both didn’t test at the same vendor at the same time.

The chromosome browser graphic visually answers the chromosome size question, but there’s more to this answer. It’s easy to see that there’s a significant difference in the physical chromosome size, but there’s more to the story.

SNPs – Chromosome Street Addresses

SNPs, known as Single Nucleotide Polymorphisms, are mutations recorded at specific addresses on chromosomes. Each chromosome holds a specific number of addresses that are read during sequencing and used for match comparison.

All of your other matches that are not parent-child and not your identical twin will match on some subset of these locations.

The Rest of the Answer – Centimorgans and SNPs

Centimorgans (cMs) are units of recombination used to measure genetic distance. You can read a scientific definition here.

For our conceptual purposes, think of centimorgans as lines on a football field. They represent distance on the chromosome.

SNPs are locations that are compared between two people to see if a match occurs.

Think of SNPs as addresses for blades of grass on that football field where an expected value occurs. If values at that address are different, then they don’t match. If values are the same, then they do match. For autosomal DNA matching, we look for long runs of SNPs that match between two people to confirm a common ancestor.

Think of SNPs as blades of grass growing between the lines on the football field. In some areas, especially in my yard, there will be many fewer blades of grass between those lines than there would be on either a well-maintained football field, or maybe a manicured golf course. You can think of the lighter green bands as sparse growth and the darker green bands as dense growth.

If the distance between 2 lines on the football field is 8 cM, for example, and there are 700 blades of grass growing there, you’ll be a match to another person if (almost) all of your blades of grass between those 2 lines match, assuming the match threshold is minimally 8 cM and 700 SNPs.

For purposes of autosomal DNA, the combination of centimorgans (distance,) and the number of SNPs (locations) within that distance measurement determines if someone is considered a match to you. In other words, you’re listed as a match if the shared DNA is over the minimum or selected thresholds. Think of track and field hurdles. To get to the end (a match), you have to get over all of the hurdles!

For example, a threshold of 8 cM and 700 SNPs means that anyone who matches you equal to or greater than both of these cumulative thresholds will be displayed as a match. Centimorgans and SNPs work in tandem to ensure valid matches.

A Second Yardstick

So, the second measure of chromosome size is the number of cMs from the beginning to the end of the chromosome, and the number of SNPs on that chromosome.

Different vendors, and different DNA testing chips cover slightly different regions. This is my match with my mother, which shows:

  • Total matching cMs on each chromosome
  • Total matching SNPs on each chromosome
  • SNP Density, which is a calculation (cM/SNPs) showing how “thick” the SNP grass is on each chromosome

The higher the matching number of cMs, especially in a row (longest segment,) the higher quality the match, and the closer the relationship.

Note that endogamous, or intermarried populations, may need separate interpretations. I discussed the signs of endogamy in this article.

Calculating Matches

Some vendors provide the ability to select your match cM and SNP thresholds, and others make those selections for you. Most vendors no longer display the number of matching SNPs, given that SNP-poor regions are, for the most part, automatically eliminated, although you can view them in your matching segment download file. In other words, the vendors simply take care of this for you. The accepted rule of thumb has always been that 500 (some said 700) or fewer SNPs was too small to be genealogically relevant, regardless of the cM match size.

Vendors include numerous and varying factors in determining match quality and potential relationships, including:

  • Total shared DNA, meaning total matching cM
  • Longest shared, meaning contiguously matching DNA block
  • X matching
  • Sex of tester (especially with respect to X matching)
  • Endogamy flags
  • Half versus fully identical DNA regions (to positively identify relationships such as half vs full siblings)
  • Triangulated segments
  • Family Matching (maternal and paternal bucketing) at FamilyTreeDNA
  • Tree matching

Not all vendors include all factors, and each vendor utilizes proprietary algorithms for features like triangulation.

The question isn’t chromosome size or even match size alone, but the quality of the match plus additive genealogical features like Theories of Family Relativity at MyHeritage to identify common and even previously unknown ancestors.

Be sure to test at the primary vendors or upload for free to MyHeritage, FamilyTreeDNA and GEDmatch to receive as many matches as possible. You just never know where that match you really need is hiding!

Enjoy!

_____________________________________________________________

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

Thank you so much.

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DNA Black Friday is Here

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5

Yes, I know it’s not Friday yet, but the DNA Black Friday sales have started, and sale dates are limited, so here we go.

These are the best prices I’ve ever seen at both FamilyTreeDNA and MyHeritage. If you’ve been waiting to purchase a DNA test for that special someone, there’s never been a better time.

Remember, to jump-start your genetic genealogy, test close or targeted relatives in addition to yourself:

  • Parents, or if both parents are not available, full and half-siblings
  • If neither parents nor siblings are available, your siblings’ descendants
  • Grandparents or descendants of your grandparents – aunts, uncles, or their descendants
  • Cousins descended from great-grandparents or other known ancestors
  • Y and mitochondrial DNA descendants of specific, targeted ancestors

For yourself, you’ll want to fish in all the ponds by taking an autosomal test or uploading a DNA file to each of the four vendors. Upload/download instructions are available here.

Everyone can test their own mitochondrial DNA to learn about your mother’s direct matrilineal line, and males can test their Y-DNA to unveil information about their patrilineal or surname line. Women, you can test your father’s, brother’s, or paternal uncle’s Y-DNA.

I’ve written a DNA explainer article, 4 Kinds of DNA for Genetic Genealogy, which you might find helpful. Please feel free to pass it on.

Vendor Offerings

FamilyTreeDNA

Free shipping within the US for orders of $79 or more

FamilyTreeDNA is the only major testing company that offers multiple types of tests, meaning Y-DNA, mitochondrial and autosomal. You can also get your toes wet with introductory level tests for Y DNA (37 and 111 marker tests), or you can go for the big gun right away with the Big Y-700.

This means that if you’ve purchased tests in the past, you can upgrade now. Upgrade pricing is shown below. Click here to sign on to your account to purchase an upgrade or additional product.

At FamilyTreeDNA, by taking advantage of autosomal plus Y-DNA and mitochondrial DNA, you will get to know your ancestors in ways not possible elsewhere. You can even identify or track them using your myOrigins painted ethnicity segments.

FamilyTreeDNA divides your Family Finder matches maternal and paternally for you if you create or upload a tree and link known testers. How cool is this?!!!

MyHeritage

The MyHeritage DNA test is on sale for $36, the best autosomal test price I’ve ever seen anyplace.

MyHeritage has a significant European presence and I find European matches at MyHeritage that aren’t anyplace else. MyHeritage utilizes user trees and DNA matches to construct Theories of Family Relativity that shows how you and your matches may be related.

Remember, you can upload the raw data file from the MyHeritage DNA test to both FamilyTreeDNA and GEDmatch for free.

Free shipping on 2 kits or more.

This sale ends at the end-of-day on Black Friday.

You can combine your DNA test with a MyHeritage records subscription with a free trial, here.

Ancestry

The AncestryDNA test is $59, here. With Ancestry’s super-size DNA database, you’re sure to get lots of matches and hints via ThruLines.

You can get free shipping if you’re an Amazon Prime member.

If you order an AncestryDNA test, you can upload the raw DNA file to FamilyTreeDNA, MyHeritage and GEDmatch for free. Unfortunately, Ancestry does not accept uploads from other vendors.

23andMe

The 23andMe Ancestry + Traits DNA test is $79, here. 23andMe is well known for its Ancestry Composition (ethnicity) results and one-of-a-kind genetic tree.

The 23andMe Ancestry + Traits + Health test is now $99, here.

You can get free shipping if you’re an Amazon Prime member.

If you order either of the 23andMe tests, you can upload the raw data file to FamilyTreeDNA, MyHeritage, and GEDmatch for free. Unfortunately, 23andMe does not accept uploads from other vendors.

Can’t Wait!!

This is always my favorite time of the year because I know that beginning soon, we will all be receiving lots of new matches from people who purchased or received DNA tests during the holiday season.

  • What can you do to enhance your genealogy?
  • Have you ordered Y and mitochondrial DNA tests for yourself and people who carry the Y and mitochondrial DNA of your ancestors?
  • Are you in all of the autosomal databases?
  • Who are you ordering tests for?

_____________________________________________________________

Follow DNAexplain on Facebook, here or follow me on Twitter, here.

Share the Love!

You’re always welcome to forward articles or links to friends and share on social media.

If you haven’t already subscribed (it’s free,) you can receive an email whenever I publish by clicking the “follow” button on the main blog page, here.

You Can Help Keep This Blog Free

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

Thank you so much.

DNA Purchases and Free Uploads

Genealogy Products and Services

My Book

Genealogy Books

Genealogy Research

Connect Your DNA Test, and Others, to Your Tree

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22

To optimize your DNA tests, each tester needs to take advantage of the features offered by each vendor.

In order to do that, we need to perform the following tasks.

  1. Upload or create a tree (except at 23andMe who does not support trees)
  2. Connect our own test to our own profile card on our tree
  3. Connect other tests we manage to their (or our) tree, depending on the vendor
  4. Connect matches who are known relatives to their profiles on our tree

Each vendor handles these situations differently, so we’ll look at each one of the vendors with step-by-step instructions for handling those situations. We all want to get the most out of the tests we’ve taken!

Plant a Tree

If you have not created or uploaded a tree at each one of the vendors (except 23andMe who does not support genealogy trees), please do so. However, 23andMe does provide for links to your tree elsewhere, so we will review that function.

I manage my “master tree” on my own computer, but I also maintain trees at both Ancestry and MyHeritage where I attach documents and research found at that vendor. I also update my ancestors at WikiTree to be sure other researchers benefit from new discoveries.

I have not uploaded my full tree from my computer anyplace because I have many private notes that are not appropriate for disclosure, not to mention speculative and unproven relationships. I created a pared-down tree at one time to upload to both Ancestry and MyHeritage, and build those trees out from there.

I’m often asked about replacing your tree at the various vendors with an updated tree. If you do that, be aware that you will lose your DNA connections and document links. I do NOT recommend that. I simply maintain multiple trees. I wrote about this in the article, “Genealogy Tree Replacement – Should I or Shouldn’t I?” If you are considering that option, PLEASE read that article first.

RootsMagic, Family Tree Maker, and Legacy Family Tree Software all provide a syncing option with various vendors and FamilySearch, although not every vendor allows access to each of those software companies. I probably should experiment with the syncing option, but given a family member’s terrible experience some years back, I’ve been unwilling to do that. My biggest fear is that I will corrupt the file and not notice it until it’s far too late to revert to a backup.

When you upload or create a tree, make sure deceased and living people are marked as such, and you’ve opted to share your tree. If you don’t, you accidentally have a private tree. Worse yet, you might not realize it. I wrote about that in Quick Tip: Trees, Death Dates and Unintentionally Private Ancestors.

Now, let’s take a look at each vendor.

23andMe

23andMe does not support traditional genealogy trees, but they do provide a location for you to link your tree at another vendor or source.

Under your name at the right side, you’ll see “View Your Profile” under the dropdown.

I’ve not been able to find a generic Ancestry tree link that will allow non-Ancestry subscribers to view my tree, but it’s easy to do at MyHeritage. Simply open your tree at  MyHeritage and just copy the link at the top. Don’t worry, people won’t see anyone living.

If you want to use “one world” types of trees, you can also link to other trees such as FamilySearch or WikiTree, but just remember that you don’t control that content.

You don’t need to connect yourself to your tree at 23andMe, because there is no genealogy tree. However, 23andMe constructs a “genetic tree” for you using your closest matches, based on how you match other people, and how they match each other.

You can view your tree under “Family and Friends,” then “Family Tree.”

I added my ancestors’ names so it’s easy to keep straight. You can do that by simply clicking on the colored circle representing the ancestor, starting with your parents.

If you know that one of your matching relatives is not in exactly the correct tree location, you can click on their circle, and then click on Edit to make modifications.

You may want to add a relative that you can identify but who isn’t connected on the tree that 23andMe constructed.

Looking on the far-right side of the tree, in the lower corner, you’ll see “Add a Relative.” Click there and follow the instructions.

Ancestry

At Ancestry, you need to link your test to “you” in a tree. Your test can only be linked to one person in one tree at a time. You can change this, but you will lose any ThruLines you currently have. They will be regenerated based on the new tree you connect your test to, but based on the tree and other factors, they may not be the same. My recommendation is if you’re going to disconnect yourself and reconnect yourself elsewhere, record everything first.

Alternatively, you can take a second DNA test and simply link that second test to another tree. IMHO, that’s a better alternative. You can leave one in place as your research tree and use the second test to experiment with.

To link your test to your tree, select the “DNA” tab. At far right, you’ll see “Settings.”

You need to tell Ancestry who you are in your tree. Click on “Settings,” then scroll to “Tree Link.”

You can also link other tests you directly manage to their placards in your tree as well.

These links allow Ancestry to form ThruLines using both DNA matches and common ancestors in trees for 7 generations.

On your DNA Match page, Ancestry will ask you if you recognize a match.

If you click on “Yes,” you’ll be asked which side the match is on.

Then you’ll be given a long list of possible relationships in most-likely to least-likely order. Literally, Erik is the last option offered.

Select and confirm.

I’m not positive exactly HOW this helps Ancestry help you, but I suspect it confirms and helps Ancestry perfect ThruLines, relationship predictions, and perhaps even “sides” of ethnicity.

I wrote about Optimizing Your Tree at Ancestry for More Hints and DNA ThruLines.

FamilyTreeDNA

At FamilyTreeDNA, every DNA test kit has its own kit number and associated tree, so you don’t need to tell FamilyTreeDNA who you are if you create a tree from scratch on their site.

FamilyTreeDNA offers a unique family matching feature that sorts your matches into maternal and paternal sides.

In order to take advantage of this, you will need a tree. You can upload a GEDCOM file, although the upload at FamilyTreeDNA does not seem to do well with very large files.

If you don’t have a GEDCOM file on your computer, you can download a tree from either Ancestry or MyHeritage and upload to FamilyTreeDNA.

I wrote about this in the article Download Your Ancestry Tree and Upload it Elsewhere for Added Benefit.

If you upload a tree, you’ll be asked to select the person in the tree that is “you,” meaning the person who tested their DNA.

You’ll want to link known matches to your tree to enable Family Matching, aka bucketing, so that FamilyTreeDNA can divide and assign your matches maternally and paternally.

If you are building your tree at FamilyTreeDNA from scratch, simply click to begin and complete the information on the placards to add your information, then your parents, building out from there. You’ll want to add the ancestral lines to connect with your closest matches on your match list.

Family matching, or bucketing, is enabled by linking known matches to their proper place on your tree. FamilyTreeDNA then evaluates each match, determining if they match a common segment with you and someone you’ve linked. If that match does share a segment with both of you, meaning they triangulate, then that person is assigned either maternally, paternally, or both. I wrote about Triangulation in Action at FamilyTreeDNA, here.

The best people to link are your parents and grandparents, of course, but that’s not always an option. You’ll want to link as many matches as you can.

To link people, either click on the Family Tree tab at the top of the page, or on the “Link on Family Tree” under Relationship Range for individual matches.

Simply click on “Link Matches,” then drag and drop your match to their placard.

Here’s an example of linking parents.

Once someone is linked, the green dot will appear signifying that they are linked, and which type of test. Green is a Family Finder autosomal test, blue means they’ve taken a Y DNA test, and pink is a mitochondrial DNA test.

If your parents aren’t available to test, link every upstream relative that you can identify. By this, I mean that your children and full siblings will match you on both sides, so aren’t helpful for parental-side assignment.

People who have DNA tests from both parents can expect around 80% of their matches to be assigned maternally, paternally, or both.

If you have relatives who have tested at other vendors, you can ask them to upload to FamilyTreeDNA for free matching.

MyHeritage

At MyHeritage, you will connect yourself and any relatives whose tests you manage to your tree.

Under “DNA,” select “Manage DNA kits.”

At the right, you’ll click on the three dots, also known as a hamburger menu (who knew.)

Select Assign (if this is a new test or a transfer) or Re-assign a kit.

Be sure to do this for every kit you manage. I made that mistake and wrote about how I discovered and fixed the problem, here. Kit assignment enables Theories of Family Relativity and other super-helpful features.

I wrote about several things you can do to optimize your chances of receiving Theories of Family Relativity, here.

You can upload DNA kits to MyHeritage from tests taken at other vendors, here.

Fish in All the Ponds

I have provided step-by-step download/upload instructors for all vendors, here. It’s important to fish in all available ponds by making sure you have DNA tests at all four vendors. Then, upload or create trees and complete this bit of housekeeping to increase your chances of catching fish!

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DNA: In Search of…Full and Half-Siblings

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This is the fifth article in our series of articles about searching for unknown close family members, specifically; parents, grandparents, or siblings. However, these same techniques can be applied by genealogists to identify ancestors further back in time as well.

Please note that if a family member has tested and you do NOT see their results, ask them to verify that they have chosen to allow matching and for other people to view them in their match list. That process varies at different vendors.

You can also ask if they can see you in their results.

All Parties Need to Test

Searching for unknown siblings isn’t exactly searching, because to find them, they, themselves, or their descendant(s) must have taken a DNA test at the same vendor where you tested or uploaded a DNA file.

You may know through any variety of methods that they exist, or might exist, but if they don’t take a DNA test, you can’t find them using DNA. This might sound obvious, but I see people commenting and not realizing that the other sibling(s) must test too – and they may not have.

My first questions when someone comments in this vein are:

  1. Whether or not they are positive their sibling actually tested, meaning actually sent the test in to the vendor, and it was received by the testing company. You’d be surprised how many tests are living in permanent residence on someone’s countertop until it gets pushed into the drawer and forgotten about.
  2. If the person has confirmed that their sibling has results posted. They may have returned their test, but the results aren’t ready yet or there was a problem.
  3. AND that both people have authorized matching and sharing of results. Don’t hesitate to reach out to your vendor’s customer care if you need help with this.

Sibling Scenarios

The most common sibling scenarios are when one of two things happens:

  • A known sibling tests, only to discover that they don’t match you in the full sibling range, or not at all, when you expected they would
  • You discover a surprise match in the full or half-sibling range

Let’s talk about these scenarios and how to determine:

  • If someone is a sibling
  • If they are a full or half-sibling
  • If a half-sibling, if they descend from your mother or father

As with everything else genetic, we’ll be gathering and analyzing different pieces of evidence along the way.

Full and Half-Siblings

Just to make sure we are all on the same page:

  • A full sibling is someone who shares both parents with you.
  • A half-sibling is someone who shares one parent with you, but not the other parent.
  • A step-sibling is someone who shares no biological parents with you. This situation occurs when your parent marries their parent, after you are both born, and their parent becomes your step-parent. You share neither of your biological parents with a step-sibling, so you share no DNA and will not show up on each other’s match lists.
  • A three-quarters sibling is someone with whom you share one parent, but two siblings are the other parent. For example, you share the same mother, but one brother fathered you, and your father’s brother fathered your sibling. Yes, this can get very messy and is almost impossible for a non-professional to sort through, if even then. (This is not a solicitation. I do not take private clients.) We will not be addressing this situation specifically.

Caution

With any search for unknown relatives, you have no way of knowing what you will find.

In one’s mind, there are happy reunions, but you may experience something entirely different. Humans are human. Their stories are not always happy or rosy. They may have made mistakes they regret. Or they may have no regrets about anything.

Your sibling may not know about you or the situation under which you, or they, were born. Some women were victims of assault and violence, which is both humiliating and embarrassing. I wrote about difficult situations, here.

Your sibling or close family member may not be receptive to either you, your message, or even your existence. Just be prepared, because the seeking journey may not be pain-free for you or others, and may not culminate with or include happy reunions.

On the other hand, it may.

Please step back and ponder a bit about the journey you are about to undertake and the possible people that may be affected, and how. This box, once opened, cannot be closed again. Be sure you are prepared.

On the other hand, sometimes that box lid pops off, and the information simply falls in your lap one day when you open your match list, and you find yourself sitting there, in shock, staring at a match, trying to figure out what it all means.

Congratulations, You Have a Sibling!

This might not be exactly what runs through your mind when you see that you have a very close match that you weren’t expecting.

The first two things I recommend when making this sort of discovery, after a few deep breaths, a walk, and a cup of tea, are:

  • Viewing what the vendor says
  • Using the DNAPainter Shared cM Relationship Chart

Let’s start with DNAPainter.

DNAPainter

DNAPainter provides a relationship chart, here, based on the values from the Shared cM Project.

You can either enter a cM amount or a percentage of shared DNA. I prefer the cM amount, but it doesn’t really matter.

I’ll enter 2241 cM from a known half-sibling match. To enter a percent, click on the green “enter %.”

As you can see, statistically speaking, this person is slightly more likely to be a half-sibling than they are to be a full sibling. In reality, they could be either.

Looking at the chart below, DNAPainter highlights the possible relationships from the perspective of “Self.”

The average of all the self-reported relationships is shown, on top, so 2613 for a full sibling. The range is shown below, so 1613-3488 for a full sibling.

In this case, there are several possibilities for two people who share 2241 cM of DNA.

I happen to know that these two people are half-siblings, but if I didn’t, it would be impossible to tell from this information alone.

The cM range for full siblings is 1613-3488, and the cM range for half-siblings is 1160-2436.

  • The lower part of the matching range, from 1160-1613 cM is only found in half-siblings.
  • The portion of the range from 1613-2436 cM can be either half or full siblings.
  • The upper part of the range, from 2436-3488 cM is only found in full siblings.

If your results fall into the center portion of the range, you’re going to need to utilize other tools. Fortunately, we have several.

If you’ve discovered something unexpected, you’ll want to verify using these tools, regardless. Use every tool available. Ranges are not foolproof, and the upper and lower 10% of the responses were removed as outliers. You can read more about the shared cM Project, here and here.

Furthermore, people may be reporting some half-sibling relationships as full sibling relationships, because they don’t expect to be half-siblings, so the ranges may be somewhat “off.”

Relationship Probability Calculator

Third-party matching database, GEDmatch, provides a Relationship Probability Calculator tool that is based on statistical probability methods without compiled user input. Both tools are free, and while I haven’t compared every value, both seem to be reasonably accurate, although they do vary somewhat, especially at the outer ends of the ranges.

When dealing with sibling matches, if you are in all four databases, GEDmatch is a secondary resource, but I will include GEDmatch when they have a unique tool as well as in the summary table. Some of your matches may be willing to upload to GEDmatch if the vendor where you match doesn’t provide everything you need and GEDmatch has a supplemental offering.

Next, let’s look at what the vendors say about sibling matches.

Vendors

Each of the major vendors reports sibling relationships in a slightly different way.

Sibling Matches at Ancestry

Ancestry reports sibling relationships as Sister or Brother, but they don’t say half or full.

If you click on the cM portion of the link, you’ll see additional detail, below

Ancestry tells you that the possible relationships are 100% “Sibling.” The only way to discern the difference between full and half is by what’s next.

If the ONLY relationship shown is Sibling at 100%, that can be interpreted to mean this person is a full sibling, and that a half-sibling or other relationship is NOT a possibility.

Ancestry never stipulates full or half.

The following relationship is a half-sibling at Ancestry.

Ancestry identifies that possible range of relationships as “Close Family to First Cousin” because of the overlaps we saw in the DNAPainter chart.

Clicking through shows that there is a range of possible relationships, and Ancestry is 100% sure the relationship is one of those.

DNAPainter agrees with Ancestry except includes the full-sibling relationship as a possibility for 1826 cM.

Sibling Matches at 23andMe

23andMe does identify full versus half-siblings.

DNAPainter disagrees with 23andMe and claims that anyone who shares 46.2% of their DNA is a parent/child.

However, look at the fine print. 23andMe counts differently than any of the other vendors, and DNAPainter relies on the Shared cM Project, which relies on testers entering known relationship matching information. Therefore, at any other vendor, DNAPainter is probably exactly right.

Before we understand how 23andMe counts, we need to understand about half versus fully identical segments.

To determine half or full siblings, 23andMe compares two things:

  1. The amount of shared matching DNA between two people
  2. Fully Identical Regions (FIR) of DNA compared to Half Identical Regions (HIR) of DNA to determine if any of your DNA is fully identical, meaning some pieces of you and your sibling’s DNA is exactly the same on both your maternal and paternal chromosomes.

Here’s an example on any chromosome – I’ve randomly selected chromosome 12. Which chromosome doesn’t matter, except for the X, which is different.

Your match isn’t broken out by maternal and paternal sides. You would simply see, on the chromosome browser, that you and your sibling match at these locations, above.

In reality, though, you have two copies of each chromosome, one from Mom and one from Dad, and so does your sibling.

In this example, Mom’s chromosome is visualized on top, and Dad’s is on the bottom, below, but as a tester, you don’t know that. All you know is that you match your sibling on all of those blue areas, above.

However, what’s actually happening in this example is that you are matching your sibling on parts of your mother’s chromosome and parts of your father’s chromosome, shown above as green areas

23andMe looks at both copies of your chromosome, the one you inherited from Mom, on top, and Dad, on the bottom, to see if you match your sibling on BOTH your mother’s and your father’s chromosomes in that location.

I’ve boxed the green matching areas in purple where you match your sibling fully, on both parents’ chromosomes.

If you and your sibling share both parents, you will share significant amounts of the same DNA on both copies of the same chromosomes, meaning maternal and paternal. In other words, full siblings share some purple fully identical regions (FIR) of DNA with each other, while half-siblings do not (unless they are also otherwise related) because half-siblings only share one parent with each other. Their DNA can’t be fully identical because they have a different parent that contributed the other copy of their chromosome.

Total Shared DNA Fully Identical DNA from Both Parents
Full Siblings ~50% ~25%
Half Siblings ~25% 0
  • Full siblings are expected to share about 50% of the same DNA. In other words, their DNA will match at that location. That’s all the green boxed locations, above.
  • Full siblings are expected to share about 25% of the same DNA from BOTH parents at the same location on BOTH copies of their chromosomes. These are fully identical regions and are boxed in purple, above.

You’ll find fully identical segments about 25% of the time in full siblings, but you won’t find fully identical segments in half-siblings. Please note that there are exceptions for ¾ siblings and endogamous populations.

You can view each match at 23andMe to see if you have any completely identical regions, shown in dark purple in the top comparison of full siblings. Half siblings are shown in the second example, with less total matching DNA and no FIR or completely identical regions.

Please note that your matching amount of DNA will probably be higher at 23andMe than at other companies because:

  • 23andMe includes the X chromosome in the match totals
  • 23andMe counts fully identical matching regions twice. For full siblings, that’s an additional 25%

Therefore, a full sibling with an X match will have a higher total cM at 23andMe than the same siblings elsewhere because not only is the X added into the total, the FIR match region is added a second time too.

Fully Identical Regions (FIR) and Half Identical Regions (HIR) at GEDmatch

At GEDMatch, you can compare two people to each other, with an option to display the matching information and a painted graphic for each chromosome that includes FIR and HIR.

If you need to know if you and a match share fully identical regions and you haven’t tested at 23andMe, you can both upload your DNA data file to GEDmatch and use their One to One Autosomal DNA Comparison.

On the following page, simply enter both kit numbers and accept the defaults, making sure you have selected one of the graphics options.

While GEDmatch doesn’t specifically tell you whether someone is a full or half sibling, you can garner additional information about the relationship based on the graphic at GEDmatch.

GEDMatch shows both half and fully identical regions.

The above match is between two full siblings using a 7 cM threshold. The blue on the bottom bar indicates a match of 7 cM or larger. Black means no match.

The green regions in the top bar indicate places where these two people carry the same DNA on both copies of their chromosome 1. This means that both people inherited the same DNA from BOTH parents on the green segments.

In the yellow regions, the siblings inherited the same DNA from ONE parent, but different DNA in that region from the other parent. They do match each other, just on one of their chromosomes, not both.

Without a tool like this to differentiate between HIR and FIR, you can’t tell if you’re matching someone on one copy of your chromosome, or on both copies.

In the areas marked with red on top, which corresponds to the black on the bottom band, these two siblings don’t match each other because they inherited different DNA from both parents in that region. The yellow in that region is too scattered to be significant.

Full siblings generally share a significant amount of FIR, or fully identical regions of DNA – about 25%.

Half siblings will share NO significant amount of FIR, although some will be FIR on very small, scattered green segments simply by chance, as you can see in the example, below.

This half-sibling match shares no segments large enough to be a match (7 cM) in the black section. In the blue matching section, only a few small green fragments of DNA match fully, which, based on the rest of that matching segment, must be identical by chance or misreads. There are no significant contiguous segments of fully identical DNA.

When dealing with full or half-siblings, you’re not interested in small, scattered segments of fully identical regions, like those green snippets on chromosome 6, but in large contiguous sections of matching DNA like the chromosome 1 example.

GEDmatch can help when you match when a vendor does not provide FIR/HIR information, and you need additional assistance.

Next, let’s look at full and half-siblings at FamilyTreeDNA

Sibling Matches at FamilyTreeDNA

FamilyTreeDNA does identify full siblings.

Relationships other than full siblings are indicated by a range. The two individuals below are both half-sibling matches to the tester.

The full range when mousing over the relationship ranges is shown below.

DNAPainter agrees except also gives full siblings as an option for the two half-siblings.

FamilyTreeDNA also tells you if you have an X match and the size of your X match.

We will talk about X matching in a minute, which, when dealing with sibling identification, can turn out to be very important.

Sibling Matches at MyHeritage

MyHeritage indicates brother or sister for full siblings

MyHeritage provides other “Estimated relationships” for matches too small to be full siblings.

DNAPainter’s chart agrees with this classification, except adds additional relationship possibilities.

Be sure to review all of the information provided by each vendor for close relationships.

View Close Known Relationships

The next easiest step to take is to compare your full or half-sibling match to known close family members from your maternal and paternal sides, respectively. The closer the family members, the better.

It’s often not possible to determine if someone is a half sibling or a full sibling by centiMorgans (cMs) alone, especially if you’re searching for unknown family members.

Let’s start with the simplest situation first.

Let’s say both of your parents have tested, and of course, you match both of them as parents.

Your new “very close match” is in the sibling range.

The first thing to do at each vendor is to utilize that vendor’s shared matches tool and see whether your new match matches one parent, or both.

Here’s an example.

Close Relationships at FamilyTreeDNA

This person has a full sibling match, but let’s say they don’t know who this is and wants to see if their new sibling matches one or both of their parents.

Select the match by checking the box to the left of the match name, then click on the little two-person icon at far right, which shows “In Common” matches

You can see on the resulting shared match list that both of the tester’s parents are shown on the shared match list.

Now let’s make this a little more difficult.

No Parents, No Problem

Let’s say neither of your parents has tested.

If you know who your family is and can identify your matches, you can see if the sibling you match matches other close relatives on both or either side of your family.

You’ll want to view shared matches with your closest known match on both sides of your tree, beginning with the closest first. Aunts, uncles, first cousins, etc.

You will match all of your family members through second cousins, and 90% of your third cousins. You can view additional relationship percentages in the article, How Much of Them is in You?.

I recommend, for this matching purpose, to utilize 2nd cousins and closer. That way you know for sure if you don’t share them as a match with your sibling, it’s because the sibling is not related on that side of the family, not because they simply don’t share any DNA due to their distance.

In this example, you have three sibling matches. Based on your and their matches to the same known first and second cousins, you can see that:

  • Sibling 1 is your full sibling, because you both match the same maternal and paternal first and second cousins
  • Sibling 2 is your paternal half-sibling because you both match paternal second cousins and closer, but not maternal cousins.
  • Sibling 3 is your maternal half-sibling because you both match maternal second cousins and closer, but not paternal cousins.

Close Relationships at Ancestry

Neither of my parents have tested, but my first cousin on my mother’s side has. Let’s say I have a suspected sibling or half-sibling match, so I click on the match’s name, then on Shared Matches.

Sure enough, my new match also matches my first cousin that I’ve labeled as “on my mother’s side.”

If my new match in the sibling range also matches my second cousins or closer on my father’s side, the new match is a full sibling, not a half-sibling.

Close Relationships at MyHeritage

Comparing my closest match provided a real surprise. I wonder if I’ve found a half-sibling to my mother.

Now, THIS is interesting.

Hmmm. More research is needed, beginning with the age of my match. MyHeritage provides ages if the MyHeritage member authorizes that information to be shared.

Close Relationships at 23andMe

Under DNA Relatives, click on your suspected sibling match, then scroll down and select “Find Relatives in Common.”

The Relatives in Common list shows people that match both of you.

The first common match is very close and a similar relationship to my closest match on my father’s side. This would be expected of a sibling. I have no common matches with this match to anyone on my mother’s side, so they are only related on my father’s side. Therefore they are a paternal half-sibling, not a full sibling.

More Tools Are Available

Hopefully, by now, you’ve been able to determine if your mystery match is a sibling, and if so, if they are a half or full sibling, and through which parent.

We have some additional tools that are relevant and can be very informative in some circumstances. I suggest utilizing these tools, even if you think you know the answer.

In this type of situation, there’s no such thing as too much information.

X Matching

X matching, or lack thereof, may help you determine how you are related to someone.

There are two types of autosomal DNA. The X chromosome versus chromosomes 1-22. The X chromosome (number 23) has a unique inheritance path that distinguishes it from your other chromosomes.

The X chromosome inheritance path also differs between men and women.

Here’s my pedigree chart in fan form, highlighting the ancestors who may have contributed a portion of their X chromosome to me. In the closest generation, this shows that I inherited an X chromosome from both of my parents, and who in each of their lines could have contributed an X to them.

The white or uncolored positions, meaning ancestors, cannot contribute any portion of an X chromosome to me based on how the X chromosome is inherited.

You’ll notice that my father inherited none of his X chromosome from any of his paternal ancestors, so of course, I can’t inherit what he didn’t inherit. There are a very limited number of ancestors on my father’s side whom I can inherit any portion of an X chromosome from.

Men receive their Y chromosome from their fathers, so men ONLY receive an X chromosome from their mother.

Therefore, men MUST pass their mother’s X chromosome on to their female offspring because they don’t have any other copy of the X chromosome to pass on.

Men pass no X chromosome to sons.

We don’t need to worry about a full fan chart when dealing with siblings and half-siblings.

We only need to be concerned with the testers plus one generation (parents) when utilizing the X chromosome in sibling situations.

These two female Disney Princesses, above, are full siblings, and both inherited an X chromosome from BOTH their mother and father. However, their father only has one X (red) chromosome to give them, so the two females MUST match on the entire red X chromosome from their father.

Their mother has two X chromosomes, green and black, to contribute – one from each of her parents.

The full siblings, Melody, and Cinderella:

  • May have inherited some portion of the same green and black X chromosomes from their mother, so they are partial matches on their mother’s X chromosome.
  • May have inherited the exact same full X chromosome from their mother (both inherited the entire green or both inherited the entire black), so they match fully on their mother’s X chromosome.
  • May have inherited the opposite X from different maternal grandparents. One inherited the entire green X and one inherited the entire black X, so they don’t match on their mother’s X chromosome.

Now, let’s look at Cinderella, who matches Henry.

This female and male full sibling match can’t share an X chromosome on the father’s side, because the male’s father doesn’t contribute an X chromosome to him. The son, Henry, inherited a Y chromosome instead from his father, which is what made them males.

Therefore, if a male and female match on the X chromosome, it MUST be through HIS mother, but could be through either of her parents. In a sibling situation, an X match between a male and female always indicates the mother.

In the example above, the two people share both of their mother’s X chromosomes, so are definitely (at least) maternally related. They could be full siblings, but we can’t determine that by the X chromosome in this situation, with males.

However, if the male matches the female on HER father’s X chromosome, there a different message, example below.

You can see that the male is related to the female on her father’s side, where she inherited the entire magenta X chromosome. The male inherited a portion of the magenta X chromosome from his mother, so these two people do have an X match. However, he matches on his mother’s side, and she matches on her father’s side, so that’s clearly not the same parent.

  • These people CAN NOT be full siblings because they don’t match on HER mother’s side too, which would also be his mother’s side if they were full siblings.
  • They cannot be maternal half-siblings because their X DNA only matches on her father’s side, but they wouldn’t know that unless she knew which side was which based on share matches.
  • They cannot be paternal half-siblings because he does not have an X chromosome from his father.

They could, however, be uncle/aunt-niece/nephew or first cousins on his mother’s side and her father’s side. (Yes, you’re definitely going to have to read this again if you ever need male-female X matching.)

Now, let’s look at X chromosome matching between two males. It’s a lot less complicated and much more succinct.

Neither male has inherited an X chromosome from their father, so if two males DO match on the X, it MUST be through their mother. In terms of siblings, this would mean they share the same mother.

However, there is one slight twist. In the above example, you can see that the men inherited a different proportion of the green and black X chromosomes from their common mother. However, it is possible that the mother could contribute her entire green X chromosome to one son, Justin in this example, and her entire black X chromosome to Henry.

Therefore, even though Henry and Justin DO share a mother, their X chromosome would NOT match in this scenario. This is rare but does occasionally happen.

Based on the above examples, the X chromosome may be relevant in the identification of full or half siblings based on the sexes of the two people who otherwise match at a level indicating a full or half-sibling relationship.

Here’s a summary chart for sibling X matching.

X Match Female Male
Female Will match on shared father’s full X chromosome, mother’s X is the same rules as chromosomes 1-22 Match through male’s mother, but either of female’s parents. If the X match is not through the female’s mother, they are not full siblings nor maternal half-siblings. They cannot have an X match through the male’s father. They are either full or half-siblings through their mother if they match on both of their mother’s side. If they match on his mother’s side, and her father’s side, they are not siblings but could be otherwise closely related.
Male Match through male’s mother, but either of female’s parents. If the X match is not through the female’s mother, they are not full siblings nor maternal half-siblings. They cannot have an X match through the male’s father. They are either full or half-siblings through their mother if they match on both or their mother’s side. If they match on his mother’s side, and her father’s side, they are not siblings but could be otherwise closely related. Both males are related on their mother’s side – either full or half-siblings.

Here’s the information presented in a different way.

DOES match X summary:

  • If a male DOES match a female on the X, he IS related to her through HIS mother’s side, but could match her on her mother or father’s side. If their match is not through her mother, then they are not full siblings nor maternal half-siblings. They cannot match through his father, so they cannot be paternal half-siblings.
  • If a female DOES match a female on the X, they could be related on either side and could be full or half-siblings.
  • If a male DOES match a male on the X, they ARE both related through their mother. They may also be related on their father’s side, but the X does not inform us of that.

Does NOT match X summary:

  • If a male does NOT match a female on the X, they are NOT related through HIS mother and are neither full siblings nor maternal half-siblings. Since a male does not have an X chromosome from his father, they cannot be paternal half-siblings based on an X match.
  • If a male does NOT match a male, they do NOT share a mother.
  • If a female does NOT match another female on the X, they are NOT full siblings and are NOT half-siblings on their paternal side. Their father only has one X chromosome, and he would have given the same X to both daughters.

Of the four autosomal vendors, only 23andMe and FamilyTreeDNA report X chromosome results and matching, although the other two vendors, MyHeritage and Ancestry, include the X in their DNA download file so you can find X matches with those files at either FamilyTreeDNA or GEDMatch if your match has or will upload their file to either of those vendors. I wrote step-by-step detailed download/upload instructions, here.

X Matching at FamilyTreeDNA

In this example from FamilyTreeDNA, the female tester has discovered two half-sibling matches, both through her father. In the first scenario, she matches a female on the full X chromosome (181 cM). She and her half-sibling MUST share their father’s entire X chromosome because he only had one X, from his mother, to contribute to both of his daughters.

In the second match to a male half-sibling, our female tester shares NO X match because her father did not contribute an X chromosome to his son.

If we didn’t know which parents these half-sibling matches were through, we can infer from the X matching alone that the male is probably NOT through the mother.

Then by comparing shared matches with each sibling, Advanced Matches, or viewing the match Matrix, we can determine if the siblings match each other and are from the same or different sides of the family.

Under Additional Tests and Tools, Advanced Matching, FamilyTreeDNA provides an additional tool that can show only X matches combined with relationships.

Of course, you’ll need to view shared matches to see which people match the mother and/or match the father.

To see who matches each other, you’ll need to use the Matrix tool.

At FamilyTreeDNA, the Matrix, located under Autosomal DNA Results and Tools, allows you to select your matches to see if they also match each other. If you have known half-siblings, or close relatives, this is another way to view relationships.

Here’s an example using my father and two paternal half-siblings. We can see that the half-siblings also match each other, so they are (at least) half-siblings on the paternal side too.

If they also matched my mother, we would be full siblings, of course.

Next, let’s use Y DNA and mitochondrial DNA.

Y DNA and Mitochondrial DNA

In addition to autosomal DNA, we can utilize Y DNA and mitochondrial DNA (mtDNA) in some cases to identify siblings or to narrow or eliminate relationship possibilities.

Given that Y DNA and mitochondrial DNA both have distinctive inheritance paths, full and half-siblings will, or will not, match under various circumstances.

Y DNA

Y DNA is passed intact from father to son, meaning it’s not admixed with any of the mother’s DNA. Daughters do not inherit Y DNA from their father, so Y DNA is only useful for male-to-male comparisons.

Two types of Y DNA are used for genealogy, STR markers for matching, and haplogroups, and both are equally powerful in slightly different ways.

Y DNA at FamilyTreeDNA

Men can order either 37 or 111 STR marker tests, or the BIg Y which provides more than 700 markers and more. FamilyTreeDNA is the only one of the vendors to offer Y DNA testing that includes STR markers and matching between men.

Men who order these tests will be compared for matching on either 37, 111 or 700 STR markers in addition to SNP markers used for haplogroup identification and assignment.

Fathers will certainly match their sons, and paternal line brothers will match each other, but they will also match people more distantly related.

However, if two men are NOT either full or half siblings on the paternal side, they won’t match at 111 markers.

If two men DON’T match, especially at high marker levels, they likely aren’t siblings. The word “likely” is in there because, very occasionally, a large deletion occurs that prevents STR matching, especially at lower levels.

Additionally, men who take the 37 or 111 marker test also receive an estimated haplogroup at a high level for free, without any additional testing.

However, if men take the Big Y-700 test, they not only will (or won’t) match on up to 700 STR markers, they will also receive a VERY refined haplogroup via SNP marker testing that is often even more sensitive in terms of matching than STR markers. Between these two types of markers, Y DNA testing can place men very granularly in relation to other men.

Men can match in two ways on Y DNA, and the results are very enlightening.

If two men match on BOTH their most refined haplogroup (Big Y test) AND STR markers, they could certainly be siblings or father/son. They could also be related on the same line for another reason, such as known or unknown cousins or closer relationships like uncle/nephew. Of course, Y DNA, in addition to autosomal matching, is a powerful combination.

Conversely, if two men don’t have a similar or close haplogroup, they are not a father and son or paternal line siblings.

FamilyTreeDNA offers both inexpensive entry-level testing (37 and 111 markers) and highly refined advanced testing of most of the Y chromosome (Big Y-700), so haplogroup assignments can vary widely based on the test you take. This makes haplogroup matching and interpretation a bit more complex.

For example, haplogroups R-M269 and I-BY14000 are not related in thousands of years. One is haplogroup R, and one is haplogroup I – completely different branches of the Y DNA tree. These two men won’t match on STR markers or their haplogroup.

However, because FamilyTreeDNA provides over 50,000 different haplogroups, or tree branches, for Big Y testers, and they provide VERY granular matching, two father/son or sibling males who have BOTH tested at the Big Y-700 level will have either the exact same haplogroup, or at most, one branch difference on the tree if a mutation occurred between father and son.

If both men have NOT tested at the Big Y-700 level, their haplogroups will be on the same branch. For example, a man who has only taken a 37/111 marker STR test may be estimated at R-M269, which is certainly accurate as far as it goes.

His sibling who has taken a Big Y test will be many branches further downstream on the tree – but on the same large haplogroup R-M269 branch. It’s essential to pay attention to which tests a Y DNA match has taken when analyzing the match.

The beauty of the two kinds of tests is that even if one haplogroup is very general due to no Big Y test, their STR markers should still match. It’s just that sometimes this means that one hand is tied behind your back.

Y DNA matching alone can eliminate the possibility of a direct paternal line connection, but it cannot prove siblingship or paternity alone – not without additional information.

The Advanced Matching tool will provide a list of matches in all categories selected – in this case, both the 111 markers and the Family Finder test. You can see that one of these men is the father of the tester, and one is the full sibling.

You can view haplogroup assignments on the public Y DNA tree, here. I wrote about using the public tree, here.

In addition, recently, FamilyTreeDNA launched the new Y DNA Discover tool, which explains more about haplogroups, including their ages and other fun facts like migration paths along with notable and ancient connections. I wrote about using the Discover tool, here.

Y DNA at 23andMe

Testers receive a base haplogroup with their autosomal test. 23andMe tests a limited number of Y DNA SNP locations, but they don’t test many, and they don’t test STR markers, so there is no Y DNA matching and no refined haplogroups.

You can view the haplogroups of your matches. If your male sibling match does NOT share the same haplogroup, the two men are not paternal line siblings. If two men DO share the same haplogroup, they MIGHT be paternal siblings. They also might not.

Again, autosomal close matching plus haplogroup comparisons include or exclude paternal side siblings for males.

Paternal side siblings at 23andMe share the same haplogroup, but so do many other people. These two men could be siblings. The haplogroups don’t exclude that possibility. If the haplogroups were different, that would exclude being either full or paternal half-siblings.

Men can also compare their mitochondrial DNA to eliminate a maternal relationship.

These men are not full siblings or maternal half-siblings. We know, unquestionably, because their mitochondrial haplogroups don’t match.

23andMe also constructs a genetic tree, but often struggles with close relative placement, especially when half-relationships are involved. I do not recommend relying on the genetic tree in this circumstance.

Mitochondrial DNA

Mitochondrial DNA is passed from mothers to all of their children, but only females pass it on. If two people, males or females, don’t match on their mitochondrial DNA test, with a couple of possible exceptions, they are NOT full siblings, and they are NOT maternal half-siblings.

Mitochondrial DNA at 23andMe

23andMe provides limited, base mitochondrial haplogroups, but no matching. If two people don’t have the same haplogroup at 23andMe, they aren’t full or maternal siblings, as illustrated above.

Mitochondrial DNA at FamilyTreeDNA

FamilyTreeDNA provides both mitochondrial matching AND a much more refined haplogroup. The full sequence test (mtFull), the only version sold today, is essential for reliable comparisons.

Full siblings or maternal half-siblings will always share the same haplogroup, regardless of their sex.

Generally, a full sibling or maternal half-sibling match will match exactly at the full mitochondrial sequence (FMS) level with a genetic distance of zero, meaning fully matching and no mismatching mutations.

There are rare instances where maternal siblings or even mothers and children do not match exactly, meaning they have a genetic distance of greater than 0, because of a mutation called a heteroplasmy.

I wrote about heteroplasmies, here.

Like Y DNA, mitochondrial DNA cannot identify a sibling or parental relationship without additional evidence, but it can exclude one, and it can also provide much-needed evidence in conjunction with autosomal matching. The great news is that unlike Y DNA, everyone has mitochondrial DNA and it comes directly from their mother.

Once again, FamilyTreeDNA’s Advanced Matching tool provides a list of people who match you on both your mitochondrial DNA test and the Family Finder autosomal test, including transfers/uploads, and provides a relationship.

You can see that our tester matches both a full sibling and their mother. Of course, a parent/child match could mean that our tester is a female and one of her children, of either sex, has tested.

Below is an example of a parent-child match that has experienced a heteroplasmy.

Based on the comparison of both the mitochondrial DNA test, plus the autosomal Family Finder test, you can verify that this is a close family relationship.

You can also eliminate potential relationships based on the mitochondrial DNA inheritance path. The mitochondrial DNA of full siblings and maternal half-siblings will always match at the full sequence and haplogroup level, and paternal half-siblings will never match. If paternal half-siblings do match, it’s happenstance or because of a different reason.

Sibling Summary and Checklist

I’ve created a quick reference checklist for you to use when attempting to determine whether or not a match is a sibling, and, if so, whether they are half or full siblings. Of course, these tools are in addition to the DNAPainter Shared cM Tool and GEDmatch’s Relationship Predictor Calculator.

FamilyTreeDNA Ancestry 23andMe MyHeritage GEDmatch
Matching Yes Yes Yes Yes Yes
Shared Matches Yes – In Common With Yes – Shared Matches Yes – Relatives in Common Yes – Review DNA Match Yes – People who match both or 1 of 2 kits
Relationship Between Shared Matches No No No Yes, under shared match No
Matches Match Each Other* Yes, Matrix No Yes, under “View DNA details,” then, “compare with more relatives” Partly, through triangulation Yes, can match any kits
Full Siblings Yes Sibling, implies full Yes Brother, Sister, means full No
Half Siblings Sibling, Uncle/Aunt-Niece/Nephew, Grandparent-Grandchild Close Family – 1C Yes Half sibling, aunt/uncle-niece-nephew No
Fully Identical Regions (FIR) No No Yes No Yes
Half Identical Regions (HIR) No No Yes No Yes
X matching Yes No Yes No Yes
Unusual Reporting or Anomalies No No, Timber is not used on close relationships X match added into total, FIR added twice No Matching amount can vary from vendors
Y DNA Yes, STRs, refined haplogroups, matching No High-level haplogroup only, no matching No No, only if tester enters haplogroup manually
Mitochondrial DNA Yes, full sequence, matching, refined haplogroup No High-level haplogroup only, no matching No No, only if tester enters haplogroup manually
Combined Tools (Autosomal, X, Y, mtDNA) Yes No No No No

*Autoclusters through Genetic Affairs show cluster relationships of matches to the tester and to each other, but not all matches are included, including close matches. While this is a great tool, it’s not relevant for determining close and sibling relationships. See the article, AutoClustering by Genetic Affairs, here.

Additional Resources

Some of you may be wondering how endogamy affects sibling numbers.

Endogamy makes almost everything a little more complex. I wrote about endogamy and various ways to determine if you have an endogamous heritage, here.

Please note that half-siblings with high cM matches also fall into the range of full siblings (1613-3488), with or without endogamy. This may be, but is not always, especially pronounced in endogamous groups.

As another resource, I wrote an earlier article, Full or Half Siblings, here, that includes some different examples.

Strategy

You have a lot of quills in your quiver now, and I wish you the best if you’re trying to unravel a siblingship mystery.

You may not know who your biological family is, or maybe your sibling doesn’t know who their family is, but perhaps your close relatives know who their family is and can help. Remember, the situation that has revealed itself may be a shock to everyone involved.

Above all, be kind and take things slow. If your unexpected sibling match becomes frightened or overwhelmed, they may simply check out and either delete their DNA results altogether or block you. They may have that reaction before you have a chance to do anything.

Because of that possibility, I recommend performing your analysis quickly, along with taking relevant screenshots before reaching out so you will at least have that much information to work with, just in case things go belly up.

When you’re ready to make contact, I suggest beginning by sending a friendly, short, message saying that you’ve noticed that you have a close match (don’t say sibling) and asking what they know about their family genealogy – maybe ask who their grandparents are or if they have family living in the area where you live. I recommend including a little bit of information about yourself, such as where you were born and are from.

I also refrain from using the word adoption (or similar) in the beginning or giving too much detailed information, because it sometimes frightens people, especially if they know or discover that there’s a painful or embarrassing family situation.

And, please, never, ever assume the worst of anyone or their motives. They may be sitting at their keyboard with the same shocked look on their face as you – especially if they have, or had, no idea. They may need space and time to reach a place of acceptance. There’s just nothing more emotionally boat-capsizing in your life than discovering intimate and personal details about your parents, one or both, especially if that discovery is disappointing and image-altering.

Or, conversely, your sibling may have been hoping and waiting just for you!

Take a deep breath and let me know how it goes!

Please feel free to share this article with anyone who could benefit.

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