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AncestryDNA Launches New Ethnicity Estimate

AncestryDNAThere has been much discussion (see here and here for a few examples) of the so-called “Scandinavian Problem” with AncestryDNA‘s ethnicity estimate, in which certain populations appeared to be over-represented in the reference panel utilized by Ancestry.com.  I, for example, have no documented Scandinavian ancestry, but had 78% Scandinavian.  Many others experienced the same issue.

The AncestryDNA team were well aware of the issues, and have been working on an update to their ethnicity algorithm, reference panel, and user interface.  Indeed, at “The First DNA Day at the Southern California Genealogy Society Jamboree” in June of this year, Ken Chahine (Senior Vice President and General Manager, DNA) gave a presentation in which he announced that the ethnicity calculations at AncestryDNA were undergoing a complete overhaul and a major update would be provided to all customers later this year.

A Limited Launch Today

Today, Ancestry.com announced on its blog (see “A Sneak Peek Into The AncestryDNA Ethnicity Update – Coming Soon To Your DNA Results!“) that as of today they “had launched a preview of the new features and results to a small random group of AncestryDNA members, which will be released to everyone in the next few months.”

According to the AncestryDNA team, about 6,000 people received the updated estimate today.  The New Ethnicity Estimate is free, and does not require any additional testing by the customer.  The remainder of AncestryDNA customers should receive their updated ethnicity estimates anywhere from 1 to 3 months, based on what I read and heard today.

Also today, several members of the genealogy blogging community attended a webinar in which the AncestryDNA team presented the updated ethnicity estimate interface and the science behind the update, and answered our questions.  As I’m sure other members of the community will agree, Ancestry.com’s transparency is greatly appreciated and benefits us all.

The Quick Summary:

Here are some of the highlights, if you’re in a hurry:

  • 6,000 AncestryDNA customers received new Ethnicity Estimates today, the rest will in approximately 1-2 months;
  • There are now 26 reference populations that your DNA is compared to;
  • The new Ethnicity Estimate appears to detect small (as small as <1%) percentages of genetic ethnicity;
  • Each estimate is the average of 40 different analyses using an algorithm called ADMIXTURE; and
  • Estimates are provided with a likely range.

My AncestryDNA Ethnicity Estimate

For the sake of comparison, here is my previous estimate from AncestryDNA (note the NEW Ethnicity Estimate Preview button – this is how you’ll know that you’ve randomly been selected for the new estimate):

AncestryDNA Results

And here is my new ethnicity estimate:

AncestryDNA Results 2

As you can see, my estimate is VERY different.  My report now reveals the trace African and Native American ancestry that comes from my Central American ancestry, and which is reported in my 23andMe report (click here to compare).  I also now have significant Great Britain and Ireland contributions, which I had expected to see based on my genealogical tree.

Clicking on one of the population names, for example “Great Britain,” changes the interface to concentrate on that information:

AncestryDNA Results

The map on the right side of the page shows the region that this category encompasses; it is primarily the U.K., but not surprisingly it can include the surrounding areas of France, Germany, Denmark, and Ireland.  Considering the recent and extensive admixture of these populations, it isn’t surprising that it can be challenging to genetically distinguish between these populations.

Below each map is a much larger section providing more information, including a comparison to the “typical” person from the selected region.

AncestryDNA Results 4

Another interesting bit of information is the other regions commonly seen for each selected estimate.  Below are the regions commonly seen in people native to Great Britain:

AncestryDNA Results 5

As another example, here is my small Native American ethnicity:

AncestryDNA Results

Because there are few Native American reference samples, it is currently extremely difficult and noisy to try to associate specific DNA with any region within North and South America.

The Ethnicity Estimate Process

If you look at the screenshots above, you’ll see for example that my Great Britain estimate is 55%, with a range of 25% to 85%.  To fully understand what this means, it’s helpful to understand how AncestryDNA calculates these numbers.

Your sequenced DNA is run through an algorithm called ADMIXTURE, which estimates the proportions of “membership” in a set of ancestral clusters, or populations.  However, this analysis is done 40 different times, and each time a random 95% of your processed raw data is used for the analysis.   After the ADMIXTURE analysis is performed a total of 40 times, the result reported to you is the mean (the average) of those 40 times.

The range provided (e.g., the 25% to 85% Great Britain in my example above) is the range obtained by the ADMIXTURE analysis within 2 standard deviations.  Therefore, on one run of ADMIXTURE I had 25% Great Britain, and on another I had 85% Great Britain.  But among the 40 different analyses, the average was 55%.

Populations that are “noisy” – i.e., are not clearly genetically distinguishable from all other populations – will have wider ranges, while less noisy populations may have narrower ranges.  For example, my Native American estimate has an extremely narrow range in part because those reference samples may not be as noisy.

Reference Panel

In the prior ethnicity estimate, AncestryDNA was primarily utilizing data gathered by Sorenson Molecular Genealogy Foundation (“SMGF”).

For the update, AncestryDNA obtained – and used their chip to analyze – DNA from approximately 3,000 individuals around the world with well-established pedigrees from their location.  For example, samples were obtained from people in France who knew, to the best of their knowledge, that their ancestry was from France as far back as they could examine.  Here is an example of locations within Europe from which new samples were obtained:

Ancestry 123a

As a result of this extensive new sampling, the AncestryDNA test is now comparing customers’ DNA to 26 reference populations (see below for a list).

AncestryDNA Results 7

 

Ancestry126a

Ancestry125a

Great Graphics and Information

In addition to the customer- and population-specific information discussed above, AncestryDNA also provides some significant new behind-the-scenes information about how the analysis is performed, including the limitations of the calculations.  Clicking on the “help” button below, with the red arrow in this figure, leads to a pop-up with more information:

AncestryDNA Results 8

 

 

Each one of the six links in the pop-up lead to screens with additional information.

AncestryDNA Results 9

Reference Populations:

Here are the 26 populations for which AncestryDNA has samples and to which it is comparing customer’s DNA:

  • Africa North
  • Africa Southeastern Bantu
  • Senegal
  • Mali
  • Cameroon/Congo
  • Africa Southcentral Hunter Gatherers
  • Ivory/Ghana
  • Benin/Togo
  • Nigeria
  • Native American
  • Asia South
  • Asia East
  • Asia Central
  • Great Britain
  • Europe West
  • Ireland
  • Italy/Greece
  • Scandinavia
  • Iberian Peninsula
  • Europe East
  • Finnish/Northern Russia
  • European Jewish
  • Polynesia
  • Melanesia
  • Caucasus
  • Near East

Blaine Bettinger

Intellectual property attorney, genealogist, and author of The Genetic Genealogist since 2007

11 Comments

  1. I’m very happy that Ancestry chose to include as much explanatory material as they did, and that they put the white paper up. I’m glad they think that their customers should have access to that information and that those of us who want it can use it, rather than making educated guesses about what their algorithms are actually doing.

    There are probably still improvements to be made (looks like now maybe in the German vs. British Isles area), but for my results, overall a nice improvement, with good supporting information.

  2. I’m one of those with a “Scandanavian Problem” to the tune of 76%. But I also have a Persian/Turkish/Caucasus problem to the tune of 14% and a somewhat less worrysome Southern European problem of 10%. But not a one ancestor in any of those Ancestry.com Ethnic areas through genealogical work back to 1600 (and some little to 1100).

    23 and Me supports a somewhat ancestry in Scandanavian areas and Southern Europe; though not western Asia. though 23 & Me does have some small bit in East Asia. 23 & Me does affirm my more central European ancestry known from genealogical work.

    I’m just afraid that Ancestry will end up classing me as mostly English of all things (though even 23 and Me also supports me at about 5% there). At times I wonder if my lower Saxon roots are now being considered Scandanavian and could just as easily be misinterpreted as “English” also.

  3. have you done 23andme as well? Did 23andme also give you 3% Native and 2% African? Glad to see there finally is an west African breakdown

  4. To understand the Scandinavian DNA in British populations, study the history of invasions by Angles, Saxons, Jutes, Vikings and Normans. To understand the Southern European DNA look to the Romans, Spanish, French, Sephardic Jews, North Africans [Moors], Berber pirates [who raided Britain and Europe from North Africa], as well as the original dark inhabitants of Britain, now found in Wales, which looked Mediterranean, and may have some connection to the Iberian peninsula. For example, dark headed Welsh singer Tom Jones and the Welsh actress Catherine Zeta Jones look more Mediterranean than stereotypically British. For those with German ancestry who find the unexpected Middle Eastern or Southern European DNA, look to Southern Germany near the Palatinate [Bavaria], to the Swiss border, to the Alsace-Lorraine near the French border, as well as to possible hidden Jewish lines or spread across the Caucasus mountains. Some dark headed Germans who migrated to the American Colonies were known as Black Deutsch or German, and many of those came to the Pennsylvania, then migrated west and south. Many dark headed Welsh or Germans even started myths of part Native American DNA in order to live in peace with their Native American neighbors, as mine did on the border of the Cherokee Nation in Northeast Georgia in the 1700′s and 1800′s. Some tried to explain their phenotypic appearance with supposed part Cherokee lines. My autosomal DNA at Ancestry was 47% Scandinavian, 30% British Isles and 23% Southern European. My autosomal test done at Ancestry DNA was 100% Western European. The test results should not be altered to conform to our expectations, just as a blood test for cholesterol should not be changed because the tested person is skeptical. The test should stand on its own. To the extent that the methodology of the tests is made available, then this information might be used as a tool to interpret the tests accurately.

    For those still skeptical of their Scandinavian results, look to the many I1 or I2 male haplotypes found in Britain, especially on the Eastern Coast. My Alstons, Ayers and Wests all have I1 or Scandinavian DNA, while my Martins and other Briish lines show variants of R1b the most common haplotype in Britain, France and the Iberian peninsula.

  5. Generally, DNA screening does not offer us with the information needed to identify a people, although it can plainly tell, using y-line or mitochondrial DNA testing, whether your direct paternal or maternal line was or was not foreign.

  6. Ancestry still has a hugh problem. I know for a fact and through DNA matches, that I have a LOT OF BRITISH ISLES, England, and Scotland. But my Ethnicity results show none for me even now. I have descended from about a zillion people from England, including 13 Mayflower Pilgrims. I match with others who have my very strong Scotitsh DNA. Most of the others show large DNA percentages of Britsh that I match. There still is something very wrong with the ethnicity results. However, I have read science articles which say you really can not tell Ethnicity way back and that it is a “fairy tale” that you can. It would be like calling the U.S. a Ethnicity type! Try to figure that one out. The “cousin” matches seem to work well though, so it was worth my money just for that.

    • Hello
      I think we have DNA matches on Ancestry.com.
      May I see your family tree.
      Thanks

  7. I have been very happy with the DNA “cousins” Matching results. The 700,000 markers of your DNA matching with others who have taken the same Autosomal DNA tests works well, because they compare the 700,000 markers with other persons 700,00 markers. That part of ancestry seems to be working well. However, there may be some part of it because it is autosomal, (and the “kinks” might not be worked out yet), that “miss” certain people who should match. I have found many, many cousin matches through the Marker results of the DNA test. And, the “cousin” matching part certainly is worth the money spent for the DNA test. But as for the ethnicity results, they should just forget about that part… according to Scientists – they warn that Ethnicity results are pretty much “meaningless.” They call it “genetic astrology”. I tend to believe the scientists. The different ethnicity types are so mixed up from the beginning of time that it is next to impossible to determine real ethnicity. I wish ancestry would just be content to sell their DNA test advertising the “cousin” matching part which does work well, even going back to the mid 1500′s, and I wish they would forget about the ethnicity part. It only makes common sense. I know by records and documented papers as I go way, way back to the 1500′s and in some cases much further, that I have a LOT of English and Scotch ancestors, and possibly some Irish, I also have quite a bit of German, French, Dutch, Swiss, and a very little Scandinavian, some Spanish (Russian is pretty much Scandinavians) way, way back. Mainly I have German, Scotch and English. As I said, the “matching cousin” part of the DNA test is well worth the price of the DNA test. Don’t take the Ethnicity result part to heart. It really doesn’t mean much.

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