The New Family Finder NGS Test Results, Comparison, and Preparation

Posted on September 14, 2026 by Roberta Estes

This article is focused on two things.

Comparison of my new NGS and the earlier Family Finder tests
How to prepare for yours if you’ve ordered the upgrade

I compared my results from my older Family Finder test with my new NGS Family Finder test results. As an early beta tester, I have two separate tests, a strategy that is not recommended because it causes duplicate matches for people within the database. Additionally, multiple kits for one person doubles the results and could skew future ethnicity research for myOrigins.

Therefore, FamilyTreeDNA has announced very attractively priced upgrades at $29 for both:

People who have taken Family Finder test directly at FamilyTreeDNA
People who have uploaded their DNA files into Family Finder from other companies

After seeing my comparison, you may want to compare your own results when they arrive, so I’ve documented that process. Warning: this took between 4 and five days because I was working with a spreadsheet with more than 15,000 rows, and I had to write scripts to perform multiple functions. It was NOT fun and I do not recommend it.

Personally, had I known then what I know now about how reliable the new NGS test is, I wouldn’t have bothered with the comparison. However, I would have downloaded my original match list for posterity, just in case.

If you purchase an upgrade to the new NGS Family Finder, your new test results will replace your older Family Finder test results, but will preserve important account features such as linked matches, any notes you have taken, and more. That’s another reason to upgrade rather than order a separate new test. They’ve done the heavy lifting, not to mention that you’ll save about $50 when compared to the price of a new test.

Why is the New NGS Family Finder Test Better?

The new NGS test holds immense promise for the future. This includes better matching, beginning now. Essentially, FamilyTreeDNA is skating to where the puck is going to be (hockey analogy) and preparing for future tools. That future is not far away!

An amazing new set of tools is goaled for release around the end of the year. And I do mean amazing. They are being beta-tested internally now.

Dave Vance spoke about the new Family Finder NGS test at the ECGGC conference in late August, which you can view through the end of 2026 if you register for the virtual conference, here, and watch the recorded sessions. You’re looking for the DNA Academy on Saturday evening. I can’t share specific preview slides with you as they are noted in his presentation as “not for distribution,” so my pen is capped for now.

All I can say is that after seeing what’s in store, people were literally throwing their billfold at the folks at the FamilyTreeDNA booth – and I do mean literally. “Here – take my money, please!” as the billfold went sailing. We all had a good laugh, but he was serious.

One presenter (not me, just in case you are wondering) left her credit card and a list of tests to upgrade while she was presenting.

They ran out of swab kits at the conference shortly after Dave’s presentation about what the future holds.

Additionally, you will also be treated to THE absolute best presentation I’ve ever seen about what NGS testing is, how it works, and how it compares to traditional tests, low-pass whole-genome tests, and medical-grade whole-genome tests.

You’ll be a passenger on the Genome Valley train, so climb aboard!

So, without spilling any beans, what’s so great about the NGS test?

To begin with, the older Family Finder tests won’t be able to provide everything the new NGS test will be able to offer – and those completely new tools are in active development today.

Why?

The NGS test targets over 280 million base pairs, up from the currently available 700,000.

That’s more than 400 TIMES the coverage.

This increases coverage in the human genome from about .02% to about 9%.

To quote FamilyTreeDNA, “This change allows us to deliver more precise autosomal results today while creating a strong foundation for future reports and tools.”

You can read the FamilyTreeDNA FAQ here.

Before we move on to the comparison, let’s talk for a minute about test types and uploads from other vendors.

Tests and Uploads

All new Family Finder tests purchased at FamilyTreeDNA since March 2, 2026 have been tested using Next Generation Sequencing (NGS), so the following matrix does not apply to those tests. Those tests don’t need to be upgraded.

If you sign on to your account, on the Family Ancestry dashboard, and see that your NGS button is grey, then you have not upgraded. Click on that grey button to read more and to upgrade. Right now the upgrade is $29, but I don’t know if that is a promotional price or permanent.

If you tested at FamilyTreeDNA prior to March 2, 2026, or uploaded a DNA file from another vendor, your test will fall into one of the following upgrade path categories.

	Tested at FamilyTreeDNA before March 2, 2026	Uploaded and purchased the Unlock	Uploaded but did not purchase the Unlock
Upgrade Path	Can use sample stored in lab if enough DNA remains*	If you purchased any other type of test at FamilyTreeDNA, they will use DNA stored in the lab if enough remains. Otherwise, you will be sent swabs.	If you purchased any other type of test at FamilyTreeDNA, they will use DNA stored in the lab if enough remains. Otherwise, you will be sent swabs.
New Swabs*	If needed, they will notify you	Yes, if needed, will notify or send swabs if you have not taken a direct test at FamilyTreeDNA	Yes, if needed, will notify or send swabs if you have not taken a direct test at FamilyTreeDNA
NGS Results	Will replace existing results	Will replace existing results	Will replace existing results

*You will be notified if enough DNA does not remain, and you will be sent new swabs. Be sure your address is current.

One of the reasons the NGS test performs better, even with existing matches from earlier tests, is because less imputation is involved. Let’s talk for a minute about imputation and how it works.

The Concept of Imputation

Most vendors change chips internally from time to time, and FamilyTreeDNA is no different. The difference this time is that the new NGS test covers exponentially more DNA than any earlier test, and all earlier tests combined. This means more than 400 times greater coverage, which in turn means less imputation is needed to compensate for the inevitable no-reads and to be compatible with files that tested different DNA locations.

Imputation is also used when comparing DNA files between vendors who don’t test the same locations.

Here’s an illustration of the concept of how imputation works.

All of the FamilyTreeDNA chip versions over the years have included about 700,000 locations, as have most other vendors. But the locations tested are not universally the same.

In our simplified concept example, FamilyTreeDNA’s tested “locations” are shown with blue cells.

The total of 20 squares shows the maximum amount of DNA tested by any of the three vendors shown, combined.

Green Vendor 1 in our illustration tests the same amount of DNA that FamilyTreeDNA tests, 12 squares, but some locations are the same and some are different. Of the 12 colored squares for both vendors, seven are the same locations, and five are not. The locations that are the same can be compared directly, but the locations that are different have to undergo special handling called imputation.

Looking at any location in our DNA, one of four nucleotides, or letters, can be present: T, A, C or G on each strand of our chromosomes, although we are only looking at one strand in our example.

Using a very simplified model of imputation, think of imputation as “filling in the blanks” using clues from surrounding letters – kind of like a crossword puzzle.

When two vendors’ data doesn’t overlap, imputation is used to fill in the blanks, as accurately as possible, for the missing data.

Using a word analogy, for vendors one and two only, we see that blue location three has no Family Finder data, where green Vendor 1 does, and the same with location five. If blue locations two and four are C and T, and three has to make a word, then there are few options. In this case, let’s say it’s cat, and location five is imputed to an A too.

Now moving to green Vendor 1, their locations two and five need to be imputed. Moving away from the word analogy, let’s look to the human genome, and let’s say that most of the time, location two is a C if location one and three are Gs. So green location two is imputed to C.

If there’s not enough quality surrounding data, imputation can’t be performed reliably. Hence, location six is still in limbo here.

You can see that in our scenario, location three is the only mismatch, out of three imputed locations. Does location three mismatch because imputation was wrong? We don’t know. Do locations two and five match because imputation was wrong? We don’t know.

All things considered, imputation is based on the science of probability, and is usually relatively reliable, but it’s still not the same as comparing actual data. The more locations that have to be imputed, and the longer the stretch, the greater the possibility of error. Every vendor implements imputation differently too. Even vendors who don’t and have never accepted uploads still use imputation internally to equalize their own legacy files from earlier test versions.

Stepping back once again to compare the four vendors, you’ll notice that pink Vendor 3 only tested half as much DNA as the blue Family Finder test and green Vendor 1, and again, not all of the same locations. That’s exactly what happened with one of the vendors last December – they dropped the number of DNA locations tested to about 400,000 from about 700,000. In our example, you can see how much would have to be imputed. Locations 11, 15, 19 and 20 can’t be imputed for the pink vendor’s file because there’s no surrounding DNA. Location 17 can’t be imputed for the green vendor for the same reason.

When vendors impute to match multiple versions of other vendors’ uploaded files, it can quickly become messy.

The answer, of course, is a “supertest,” which tests all of the locations that overlap everyone, including that vendor’s own earlier tests.

Welcome to Family Finder NGS, shown in orange at the bottom of our example comparison.

As you can see, the orange NGS test covers all of the locations tested by all of the other tests.

NGS is targeted testing for a specific set of locations that are known to undergo mutations in the human genome and provides extremely high-quality results. Imputation for the NGS file is rarely necessary, although imputation for the other vendors’ and earlier file versions is still required for them to match to each other.

This is exactly why the upgrade is recommended, and why there’s no benefit to retaining your old test. The NGS test tests far more data and provides much more reliable matching.

NGS is the great equalizer.

NGS Test Comparison Process

I took my NGS test during the initial R&D development and testing phase, so my original Family Finder test was not upgraded. This afforded me the opportunity to compare the two results.

I downloaded the match files for both of my tests, the original Family Finder and the new NGS Family Finder test, color-coded the background of the cells, not the text inside the cells, and dropped them into a single combined spreadsheet.

It doesn’t matter what colors you choose, but be sure you can easily see the difference. I used apricot for the original Family Finder test matches and light purple for the new NGS test.

As we walk through these results together, you’ll notice that I continue to refer to them by color. In part, that’s so I can maintain my own sanity as I compare results. When I write these types of articles, I have to check and recheck results.

When the same person showed as a match to both tests (meaning they had both an apricot and purple row), I calculated the difference in matching amounts of DNA (cMs) between the match’s results on both tests. I added several calculation columns, which are not shown above.

I’ll tell you, this was not a trivial exercise. It was painful and I really don’t recommend it.

Let’s take a look at the results.

Total Matches

I have some matches with the new NGS test that I do not have with the legacy Family Finder, and I have some matches on the older test that are no longer present on the NGS test.

	Old Family Finder (apricot)	NGS Family Finder (purple)	Difference
Total Matches	9014	7719	1,295
Maternal	1665	Not linked
Paternal	3783	Not linked
X-Matches	2198	1849	349

I have not yet linked the same matches in my NGS test, so I can’t compare the number of maternal and paternal matches. Fortunately, when you upgrade an existing test, FamilyTreeDNA preserves your linked matches, so you won’t need to relink.

Relationship Estimates

	Old Family Finder (apricot)	NGS Family Finder (purple)
1^st-2^nd cousins, Great/Half Uncle/Aunt/Niece/Nephew, Great-Grandparent/Grandchild	6	6
1^st-3^rd cousin	1	1
2^nd-3^rd cousin	5	4
2^nd-4^th cousin	127	132
3^rd-5^th cousin	1937	1900
4^th to remote	6938	5676
Total	9014	7719

The closest relationships remained the same. One 2^nd-3^rd cousin moved to the 2^nd-4^th cousin range by losing 10 cM, 194 cM to 184 cM, but they were apparently on the threshold anyway. That match is actually my second cousin, so both ranges are accurate. It was also a transfer kit, so they did not test at FamilyTreeDNA. This revised match is probably the difference between actual reads and imputed reads in some regions, meaning the match is now more accurate.

275 matches had a predicted relationship change, but not uniformly in one direction, and no one moved more than one category in either direction. This all makes sense.

Match Differences

	Number
Matches found in both the apricot and purple spreadsheets	7,352
Unique (comparable) matches in both spreadsheets	7,174
Matches in original Family Finder apricot only	1,681
Matches in NGS purple only	400

A total of 7,352 matches appear in both spreadsheets, meaning the apricot and purple names matched exactly.

Unfortunately, some people had multiple tests, so I couldn’t always compare apples to apples because they appear three times or more on the combined spreadsheet, and I don’t know which of their kits are which.

If someone with the same exact name had more than one match for either or both tests, I did not compare them because their matching amounts were different, and I didn’t know which one(s) my old test matched, versus which one(s) my new test matched. Usually, one was an upload and one was a test at FamilyTreeDNA, but not always. I excluded those 178 match rows from the analysis.

Therefore, 7,174 matches could be directly compared.

There were 1,681 people who match ONLY on the old Family Finder test, and 400 that match only on the new NGS test. And yes, I downloaded the match files at the same time on the same day, so this comparison was controlled for any time difference.

cM Differences

	Number
Largest apricot match not in purple (NGS) list	26.3 cM
Largest purple (NGS) match not in apricot list	27.63 cM
Largest difference	69.86 cM NGS kit more

NGS detected greater over 10 cMs	19
NGS detected less over 10 cM	7

Total NGS greater	2,924
Total NGS less	3,040
No change	1,090

The largest value difference where a match appeared in the original apricot Family Finder test, and not in the purple NGS test, was 26.3 cMs.

The largest value difference where a match appeared in the NGS purple Family Finder test, and not in the apricot original Family Finder test was 27.63 cMs.

The largest difference between the two tests was 69.86 cMs larger detected by the NGS test. This match was a known second cousin whose matching cMs went from 373.06 to 442.92, but the longest block only increased a negligible amount from 87.47 to 87.69.

The next largest difference was with a 1C1R with a 41.56 cMs difference, also with the NGS-detected value being larger.

In all cases where the number of differing cMs was 16 or greater, the NGS had detected more.

There were very few tests that differed more than 10 cMs. In 19 cases, the NGS test detected a greater difference of 10 cMs or higher, meaning if the original test value was 100 cMs, in the NGS test, it was 110 cMs or greater.

In 7 cases the NGS test detected a smaller difference of 10 cMs or more, meaning that if the original test value was 100 cMs, in the NGS test, it was 90 cMs or smaller.

Out of the 7,174 tests being compared, 19 tests with greater than a 10 cM variation isn’t very many, around 0.26%.

In total, 1,090 matches had no change at all, while 2,924 NGS matches had more matching DNA detected, and 3,160 matches had less.

All but 287 of those differences were less than 5 cMs, and 6778 were less than 1 cM. In other words, literally not worth counting.

myOrigins Ethnicity

We all know to expect changes in our ethnicity from time to time at all vendors. The NGS test is exciting because it covers a much larger portion of our genome. As more people test, the reference library also becomes larger, which means that the ethnicity predictions can and will become more refined too

myOrigins	Old Family Finder (apricot)	NGS Family Finder (purple)
Central Europe	57%	52%
England, Wales, Scotland	28%	33%
Ireland	15%	14%
Magyar	<1%	<2%
AmerIndian Andes and Caribbean	<1 (see below)	N/A
AmerIndian North America	<1% (chr 1 & 13)	<1 (chr 1 & 2)
Anatolia, Armenia, Mesopotamia, North Africa	<1 (chr 13)	<1% (chr 10)

None of my major categories changed, but the amounts attributed to each category changed somewhat.

Trace regions, which are less than 1%, shifted some as well, as did their chromosome locations.

For me, this is particularly interesting, because I paint my ethnicity segments at DNAPainter in order to overlay my Native American segments over the matches with whom I’ve identified common ancestors.

Those segments, matches, and ancestors, taken together, help identify the source of the Native American segments.

My Native segment on chromosome one stayed essentially the same, but the Native segment on chromosome 13 is not present on the new NGS test. However, a new Native American segment is now shown on chromosome 2 in the same location that 23andMe also shows a Native American segment.

Chromosome one has already been proven to a Native American ancestor on my mother’s side, but I have hit a brick wall on the chromosome 13 segment. Now, I’ve painted the Native Segment on chromosome 2 and it aligns with the same ancestral line as my Native American segment on chromosome 1.

My Middle Eastern/North African segment still exists, but the location has changed. This segment was adjacent to my Native American segment on chromosome 13 before, on my father’s side, which suggested a history of enslavement. I thought I knew which ancestral line they both descend from, but now I need to review my matches and reconsider.

Unfortunately, my parents are both deceased and there’s no DNA available, so I cannot upgrade their tests or purchase new ones for them. No aunts or uncles are available either. In this case, cousin matches and their associated genealogy on those segments become critically important.

Native American and African American segments are often the best, and sometimes the only hints we have to find and identify those ancestors.

Preparing for Your NGS Results

To be very clear, you don’t necessarily need to compare or prepare, BUT, if you order an upgrade to an existing test, your old match list will be replaced with the new one. Your old match list will not be preserved unless you do it.

What may change?

Your ethnicity results will probably change somewhat
You will have matches you did not have before
Some existing matches, especially at low matching levels, will no longer be there
The amount of DNA you share with some people will change

Important: Any notes you have recorded on your matches and any matches that you have linked will be preserved and carried over to your new results when your new test is complete.

If you want to preserve your matches from your earlier test, or your myOrigins results, you’ll need to download your match list, and either download or take screenshots of your ethnicity information.

Ability to Download	Tested at FamilyTreeDNA before March 2, 2026	Uploaded and purchased the Unlock	Uploaded but did not purchase the Unlock
myOrigins	Can download	Can download	Cannot download
Chromosome Painter (ethnicity)	Can download	Can download	Cannot download
Match list with segment and other information	Can download	Can download	Cannot download
Raw data file	Can download	Cannot download*	Cannot download*

*On tests you uploaded, you don’t need to download the raw data file because you already have it from the originating vendor.

What information is included in your Match List download file?

Match name
Relationship Range
Shared Data cMs
Longest Block cMs
Linked Relationship (if you linked them in your tree) – this feature is what allows FamilyTreeDNA to assign your matches maternally, paternally or to both sides using triangulation
Ancestral Surnames that they’ve entered
Y-DNA Haplogroup if applicable
mtDNA Haplogroup if applicable
Notes
Paternal/Maternal or Both side(s) match (if you’ve linked people and this match can be assigned using triangulation. (This is why it’s important to link as many people as possible to their place in your tree.)
X-Match cMs
Autosomal Transfer yes/no

If you match the same person on the NGS test, this information is preserved for that match.

Where to Download

You must have 2FA (Two-Factor Authentication) enabled for all downloads.

The files you may want to download are found on your dashboard in two locations.

Family Finder Matches
Chromosome Painter (ethnicity)

Family Finder Matches Download

To download your list of matches with their complete information, click on Family Finder Matches on the dashboard, then on “Export CSV.”

This download provides all the fields mentioned above, whereas the Chromosome Browser segment download provides only your matching segment data, without the additional information.

Download MyOrigins Ethnicity Segment Data

To download your myOrigins ethnicity segments, click on Chromosome Painter on your dashboard, then on “Download Segments.” You can also view or copy those segments by viewing the Detailed Segments tab.

I paint these segments at DNAPainter so that I can correlate my ethnicity regions with my ancestors’ segments.

To assign segments accurately, it helps immensely to have at least one parent’s DNA results too, and preferably both.

You may also want to take a screenshot of your myOrigins map. Note the left-side scroll bar when you’re taking screenshots.

What’s Next?

What else can you do at FamilyTreeDNA to benefit your genealogy?

If you haven’t already, upload a GEDCOM file or create a tree at MyHeritage, and link your Family Finder test to your results.
Link your individual matches to their place in your tree. This allows FamilyTreeDNA to use segments triangulated with linked matches to assign other matches to either the maternal or paternal side of your tree, or both.
Add your line to WikiTree. It’s easy. Begin with yourself and add ancestors until you connect with someone who is already in WikiTree. For me, it was the grandparent level.
Add your WikiTree link to your FamilyTreeDNA account under the gear in the upper right-hand corner, then Genealogy, then Family Tree. This gives your matches an easy way to identify common ancestors by using WikiTree’s Find Relationships feature, and provides two types of tree resources for you and your matches – MyHeritage and WikiTree.
Make sure your Earliest Known Ancestor information is correct and up-to-date with your most recent research, including a specific map location. You’ll find that under the gear too, then Genealogy, then Earliest Known Ancestors.
Add your surname list to your profile under the gear, Genealogy, Surnames tab.
Use the Matrix tool at FamilyTreeDNA to see how much DNA your shared matches share with each other.
Y-DNA – If you’re a male, test your Y-DNA, which is your father’s direct paternal line. The Big Y-700 test provides you with matches and the most detailed information possible.
mtDNA – Everyone can take a mitochondrial DNA test, which shows matches and provides information about your mother’s direct matrilineal line.
Use Advanced Matching, found under Additional Tests and Tools on your dashboard page, near the bottom, which allows you to select from multiple tests to see who matches you on both types of tests. For example, those who match you on both your full sequence mtDNA test and your Family Finder test.
Join projects relevant to your family surname, geography or broader interests. You’ll find Group Projects in the top banner of your dashboard page after signing in.
Utilize the Discover tools for both Y-DNA and mitochondrial DNA results.

Check your matches often to see who is new and what might have changed as people upgrade to the new NGS test and more people test.

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DNA Purchases and Free Uploads

FamilyTreeDNA – Y-DNA, mitochondrial and autosomal DNA testing
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AncestryDNA – Autosomal DNA test
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Genealogy Products and Services

MyHeritage Subscription with Free Trial
Legacy Family Tree Webinars – Genealogy and DNA classes, subscription-based, some free
Legacy Family Tree Software – Genealogy software for your computer
OldNews – Old Newspapers with links to save to MyHeritage trees
MyHeritage Omni comprehensive “everything included” subscription plan
Newspapers.com – Search newspapers for your ancestors
NewspaperArchive – Search different newspapers for your ancestors

My Books

DNA for Native American Genealogy – by Roberta Estes, for those ordering the e-book from anyplace, or paperback within the United States
DNA for Native American Genealogy – for those ordering the paperback outside the US
The Complete Guide to FamilyTreeDNA – Y-DNA, Mitochondrial, Autosomal and X-DNA – for those ordering the e-book from anyplace, or paperback within the United States
The Complete Guide to FamilyTreeDNA – Y-DNA, Mitochondrial, Autosomal and X-DNA for those ordering the paperback from outside the US

Genealogy Books

Genealogical.com – Lots of wonderful genealogy research books
American Ancestors – Wonderful selection of genealogy books

Genealogy Research

Legacy Tree Genealogists – Professional genealogy research

The New FamilyTreeDNA NGS Family Finder Test

Posted on March 30, 2026 by Roberta Estes

Click on any image to enlarge

Recently, in a press release, FamilyTreeDNA announced a new version of their Family Finder autosomal test that increases coverage from about .02% to about 9% of the human genome. Increasing coverage to this level using precision genomics holds great promise for the future.

Everyone who has purchased a Family Finder test since the beginning of March is automatically tested using the new technology – and it doesn’t cost any more than the earlier test.

Image not to scale because if it was, you would be able to see the bottom line at all:) This is meant to convey the message of more data!

As shown in this slide presented by Dave Vance, Senior VP and General Manager at FamilyTreeDNA, the new test covers 400 times more DNA locations than the industry-standard microarray chip-based test.

The typical vendor microarray autosomal DNA test covers somewhere between 400,000 and 750,000 locations.

Utilizing this new technology is an investment in the future.

You Don’t Know What You Don’t Know

To quote Dave:

Two numbers I want you to remember.

0.02 is the percent of your whole genome reported by standard autosomal tests today. All of your ancestry estimates, shared segments, and autosomal matches come from that small fraction.

9 is the percent of your genome that our new Family Finder test reports at high quality coverage. Starting right now — that’s over 400 times more data, from the very same test.

And the real point isn’t the number. It’s what that data makes possible. This gives us the foundation to unlock deeper, more meaningful insights — not just today, but for years to come. And when it becomes possible to go even further, I want FamilyTreeDNA to lead the way.

But what does that 9% mean for your genealogy research?

It means fewer unexplained matches, a clearer understanding of how people are related, and more confidence in the conclusions you draw from your autosomal DNA. Moving from connections to explanations, and from data to answers.

And until we can start rolling out those deeper insights, for now you’ll still get the same trusted Family Finder experience you’re used to — but you’ll also have the benefit of data that’s ready to unlock even more as new insights become possible.

In fact, you can watch Dave for yourself, at RootsTech, on the mainstage, here, having the unenviable position of following the Irish-step-dancing Gardiner Brothers. Yea, Dave, I didn’t get that gene either!

What makes NGS sequencing so special?

Sequencing Types

NGS is the abbreviation for Next Generation Sequencing, also called massive parallel sequencing. Rather than using individual probes, NGS is a high-throughput technology that simultaneously sequences millions of DNA fragments while still allowing targeting of specific regions.

Dave wrote about the differences between different types of sequencing, here.

All vendors select or target locations in the human genome that are most relevant for their product set, purpose or goals.

The older microarray sequencing machines have been in use for many years. They use probes to read specific targeted addresses, one by one, identifying which of four nucleotides is present at each location on your two copies of each chromosome.

The four nucleotides, adenine (A), thymine (T), cytosine (C), and guanine (G) are the building blocks of DNA, and you receive one from each parent at every location on chromosomes 1-22. Chromosome 23, the sex selection chromosome is a little bit different due to X-DNA and Y-DNA, but the locations are still read the same way using NGS technology.

The results of DNA testing are essentially a downloadable output file with the following information for each read:

The RSID SNP cluster ID chromosome
The chromosome number
The position (think street address) on the chromosome
The results, which are the abbreviations for the nucleotide found on the first and second strands of your DNA at that location

In autosomal DNA testing, positions on strands cannot inherently be identified as maternal or paternal without additional techniques such as parental comparison or phasing.

This data file is not meant for you to analyze, but for computers to compare to other DNA testers. Needless to say, the power of the data lies in the information it holds, such as ethnicity, haplogroup-identifying mutations, and matching with other testers.

The output files must be compatible with each other, or the vendors must make accommodations for any incompatibility.

Regardless of the sequencing type, currently, all genetic genealogy vendors’ download files use this same pattern.

The difference between the files and file types from each vendor is:

The technology used for the test
How much DNA is tested
How many rows of data are provided in the download file
The quality of the results

Sequencing Type Differences

Let’s put this in terms that we all understand.

With microarray sequencing, a utility worker is sent to each address to read the two nucleotides.

With both NGS and whole-genome sequencing, many addresses are read at the same time. Think of a fleet of drones flying over a neighborhood and reading what is written on the rooftops of each house address.

The difference between the type of NGS sequencing utilized by FamilyTreeDNA, and whole-genome sequencing is threefold:

NGS targets specific addresses and neighborhoods in a controlled manner, because we know they are useful and are specifically interested in the data at those locations. In other words, it omits oceans, deserts, and other places that we know aren’t useful for genealogy.
Whole-genome sequencing covers the majority of the genome, even though more than 90% of the genome is identical in all humans. In other words, the fleet of whole-genome sequencing drones flies over everything, including oceans and deserts, reading and storing everything.
The number of times the drones fly over each address.

For example, a low-pass whole-genome test would fly over the entire world (your genome), scanning it once or twice, but there will be cloud cover and weather in some locations. Typically, you want at least two complete reads from each address to compare to ensure a minimum level of quality. The missed areas need to be estimated with tools like imputation to fill in the blanks.

The breadth of DNA covered is known as “coverage”, or “pass coverage”. So, whole-genome testing covers all or most of the genome, including more than 90% that is not genealogically relevant because it’s identical in all humans.

With NGS sequencing, you specify which locations or neighborhoods you want the drones to read, and you instruct them to fly over just those regions, say, 5 or 10 times. Even if there’s weather or another issue, chances are that at least some of those passes will be able to read both nucleotides.

How many times a particular location, or base, is read is known as “read depth” or “sequencing depth”. The greater the depth, the higher the quality and accuracy of the targeted locations, which means less imputation or “fixing” is needed.

Within the industry, confidence to coverage correlation is about 93% confidence of accuracy for both alleles at a given location at a depth of 5X, which rises to about 99% accuracy at a depth of 10X.

Using our examples, whole-genome sequencing covers about 98% of the genome, at a depth specified by the vendor. Low-pass whole-genome testing is typically performed at a depth of 2X, meaning each location is scanned twice.

NGS combines the best aspects of both “drone style” and “targeted” reads, providing the highest accuracy for the areas that are most important for genetic genealogy at an affordable price, while also targeting enough of the human genome to allow for new discoveries that may be important to either population genetics for ethnicity identification, or to identify your own family lineage mutations.

Yes, you can get both high coverage and very deep reads. That’s called medical-grade whole-genome sequencing, where your entire genome is sequenced to a depth of at least 30X, but it’s both expensive and not useful for genealogy. None of the genealogy vendors are prepared to, or need to, process the massive amount of data generated by a medical-grade whole-genome test, so there is no benefit to taking that type of test for genealogical purposes.

Why is NGS Sequencing Important?

FamilyTreeDNA has moved from the 700,000+ SNPs previously read on their microarray chip, to more than 280 million base pairs. So, from about .02% to about 9% of the 3.1 billion base pairs of the human genome.

Technology has improved to the point where NGS sequencing is no more expensive than microarray sequencing and provides substantially more results.

In other words, there’s no reason NOT to implement this technology now. The new Family Finder test is fully compatible with their earlier Family Finder tests, so everything is painless.

Plus, NGS allows FamilyTreeDNA to target specific locations that benefit their customers, such as both Y-DNA and mitochondrial DNA SNPs. Of course, you’ll still need to take the Big Y-700 or the full sequence mitochondrial DNA (mtDNA) test for full results and matching – but males will receive a confirmed Y-DNA mid-level haplogroup now, with midrange mtDNA haplogroups coming in the future for Family Finder testers. This is a feature that other vendors don’t target or provide at the same level.

I’m very hopeful that these foundation haplogroups will serve as an “appetizer” and will encourage more people to take both the Big Y-700 (males only) and the mtFull test (for everyone), as applicable, to receive those types of specific matches and learn more about their ancestors.

Speaking of the future, how do you future-proof your DNA?

Future-Proofing Your DNA

If you’ve already tested, should you purchase a new Family Finder test for yourself now?

No.

I know you didn’t expect that answer, but here’s why.

Everyone who purchases a Family Finder test, which uses NGS technology, receives the same matching and features as the legacy test.

FamilyTreeDNA doesn’t yet know the benefits and discoveries that will eventually be available, and they won’t know until after they have results of customers to work with.

Having said that, you will definitely want to future-proof your DNA and the results of anyone whose results you count on to help sort through your own.

So, let’s make a plan!

Assuring Future Compatibility

Plan 1 – Test Your Relatives:

Your closest relatives are your best assets. They help you determine how you match others, who you share ancestors with, and the identities of those ancestors. You absolutely need to test the following relatives if they are available:

Parents
Grandparents
Siblings, both full and half – test all of them if both parents aren’t available for testing.
If your sibling(s) are deceased or not available, their children carry half of their DNA, but not the same half, so test everyone available. You don’t need to test your siblings’ children if that sibling is available to test.
Aunts and uncles, or their descendants if they are not available
Great-aunts and uncles, or their descendants if they are not available
First and second cousins

Plan 2 – Person Has Never Tested:

If you or they have never taken the Family Finder test at FamilyTreeDNA, order a Family Finder test now. Depending on the circumstances and how you relate to them, also consider adding a Y-DNA or mitochondrial DNA test as well.
If you have taken a Y-DNA or mitochondrial DNA test at FamilyTreeDNA, upgrade to a Family Finder test now.

Plan 3 – Already Tested at FamilyTreeDNA:

If they or you have already taken a Family Finder test at FamilyTreeDNA, an upgrade offer will be forthcoming soon. You don’t need to do anything now.
If the person is critical for your research, elderly, or there is some other reason for concern, the tester or kit manager can contact FamilyTreeDNA customer support now and inquire whether or not there is an unopened vial of DNA.
To assure that there is enough DNA left for the future, or that the DNA sample is not too old, you can request that a “C/D vial” set be sent to you/them just in case. Be sure the current address is valid.
This is also a good time to be sure that your/their Beneficiary Information and/or Kit Manager information is current as well. You’ll find both under Account Settings beside the name in the upper right corner of the page.

Plan 4 – Uploaded From Another Vendor:

If you uploaded your DNA file to FamilyTreeDNA from another vendor instead of testing there, hold your horses for now. You’ll clearly have to swab, because when you do an upload, only the data file is uploaded. No DNA is actually transferred or uploaded. I’m not sure what process will be put in place for transfer/uploaded testers, but FamilyTreeDNA will let you know when something is available.

What NOT to Do

I contacted FamilyTreeDNA and this is what they ask customers NOT to do:

Don’t request that your current test be deleted so you can order a new one. This removes everything – linkages, trees, family matching, permissions, project membership, other tests, and notes. Not just for you, but for your matches who have done work on their match with you as well.
Don’t order a second kit, which causes “twins” in the system. I don’t have inside knowledge, but I’ll bet there will be special upgrade pricing if you just wait a bit!

I’m Excited

I don’t know what the future holds, but I’m hoping for:

More granular ethnicity (we always want that, right?)
More confident matching
Improved relationship identification
Additional tools to identify descendants of specific ancestors
Tools to identify missing ancestors

As a contract member of the R&D team, I’ll let you know when my NGS results are back and how they compare to my matches on the current chip. You know I’m building that spreadsheet already!!