Calling HOGWASH on 23andMe’s Ancestry Timeline

Every now and then, I’m aghast when I look at a product and wonder how the devil it ever escaped the lab.  Is there no quality control?  And who thought it was a good idea, anyway, and why?

23andMe’s new Ancestry Timeline, released last week, is one of those.

Not only is it incorrect, but it deceives people into believing something that isn’t true.

Let’s take a look.


My Ancestry Timeline at 23andMe is shown above. I notice that my Middle Eastern/North African is missing from the timeline.  It’s less than 1%, but then so is my Native American which is included.

You can see in the text underneath the timeline that 23andMe says this timeline reflects how long ago my MOST RECENT ancestor in that geographic location was born.

Let’s compare this with reality.  You may recall that I recently wrote the article, Concepts – Calculating Ethnicity Percentages. In that article, I utilized my known and proven genealogy for my 64 great-great-great-great-grandparents to calculate what my ethnicity results should look like.  I’m referring to the same chart of my 64 ancestors for this exercise as well, since I’ve already done a great deal of the work.  Let’s see how reality stacks up to the 23andMe timeline.

On the chart below, I’ve shown the geographic category, the dates from the 23andMe timeline reflecting my most recent ancestor’s birth, my most recent ancestor from that location, and the accuracy of the 23andMe estimate.

Category 23andMe Dates My Most Recent Ancestor Birth 23andMe Accuracy
British and Irish 1900-1930 1759 – Henry Bolton Utter hogwash
French and German 1840-1900 1854 – Hiram Ferverda Close
Scandinavian 1750-1840 No ancestor More hogwash
Eastern European 1720-1810 No ancestor Hogwash
Italian 1690-1810 No ancestor Hogwash
Native American 1690-1790 Uncertain, mother’s side – early 1600s, father’s side – unknown Not verifiable, reasonable

The part of this equation that I find extremely upsetting is the sheer magnitude of how misleading the 23andMe timeline is.  It’s not just wrong, it’s horribly deceptive – massively inaccurate by any measure possible.

Here’s what the 23andMe white paper says about this new tool:

“Admixture date estimator is a 23andMe feature that enables customers to find out, for each of the ancestries they carry, when they may have had an ancestor in their genealogy who was likely to be a non-admixed representative of that population.”

I’m a seasoned genealogist, so I know unquestionably that my 23andMe Timeline is not only wrong, it’s entirely hogwash in 4 of 6 categories. A 5th category is close, and the 6th is reasonable but not verifiable.

The disparity of the British/Irish dates between 1759 when Henry Bolton was born in London and 1900-1930 is evident without discussion.  I do have a lot of British Isles ancestry, but it’s a result of many ancestors, not one and no one born there even remotely recently, let alone within the past generation. For me, someone born between 1900-1930 would be a parent.

Looking back at the Calculating Ethnicity Percentages article, you’ll note that I don’t have any Scandinavian ancestors in any known generation.  The 8% that 23andMe estimates, if accurate, equates to between a great-grandparent at 12.5% and a great-great-grandparent at 6.25%.  If the Scandinavian was one person, they would have been born in that timeframe (1750-1840) – but there was no one person.  The Scandinavian has to be very ancestral, meaning ancient Vikings or Normans or found in the Dutch population which is often found to be “Scandinavian.”  Regardless, there are no Scandinavian ancestors in my pedigree which reaches back well before 1750-1840.  Neither are there any Eastern European or Italian ancestors. None. Nada. Zip.

Perplexingly, it’s that unverifiable category, Native American, that so many people are desperately researching and scavenge for any possible clue.  There is no way to determine whether that category is right or wrong, so they will assume that it is accurate.  However, judging from the track record of the other categories – it’s more likely to be incorrect than correct.  Resorting to history alone, we know that the first European settlers arrived in North America in the early 1600s and my Native heritage is small, based on both my genealogy and my DNA, so a range of 1690-1790 would be a “good guess” with no genetic information at all.  My proven Native ancestors were born in the early/mid 1600s, but I have not successfully identified all of my Native ancestors, in particular the one(s) from my father’s side and when they were fully Native.

For a beginner or someone with unknown parentage, this timeline is horribly, horribly midleading and will cause novices to make massively incorrect assumptions. A British or Irish ancestor born between 1900-1930? Seriously?  This timeline combined with the 39.8% British/Irish suggests a parent.  Think about what an adoptee would take away from this timeline – and how their research could be derailed as a result.  Without parents available to DNA test, this erroneous information could make someone question their parentage.

Here’s an example of just how misleading this information can be.

In my case, I know beyond a doubt that my mother was primarily descended from German and Dutch recent immigrants with some French and Native American (Acadian) thrown in for good measure.  So, based on this timeline stating that a British/Irish ancestor was born in the British Isles between 1900 and 1930, combined with my ethnicity results of 39.8% British and Irish, OH MY GOD, my father is not who I thought, but is some British/Irish man.  MOTHER………………

All I can say is thank goodness I’ve done the DNA testing that I have and I know beyond a shadow of a doubt that my father is my biological father and not some British man, despite what this timeline suggests.  If I had no other evidence – I certainly would believe that my father was a British man, and I’d be GRATEFUL for this (highly erroneous) information.

On the flip side, many people will utilize this tool to “confirm” suspicions about genealogy.  I’ve already seen this happening on various lists.  With 4 of 6 categories being entirely, provably, incorrect, not to mention that the first category reflecting my largest percentage of ethnicity is so dramatically wrong, one can have absolutely no confidence in any of the other categories. I can’t and neither can anyone else.

I’m not alone either.  This, from another long-time genealogist: “I am dumbstruck.  It couldn’t be further from the truth for me.  I am very colonial on both sides.  Most recent immigrant ancestor was 1797.”  And from another: “No.  Just no.  Not accurate.”

So let me say this again.

You. Can. Have. No. Confidence.

If you already know your genealogy, then you don’t need this tool.  If you don’t know your genealogy, then you’re going to be misled by this tool.

It’s very clear that anyone with many ancestors that came from a particular population, but that haven’t been born in that location in many generations will have an incorrect timeline.  This would include just about everyone with colonial American roots.  The amount of a particular ethnicity does NOT equate to aggregating that ethnicity into a single ancestor and equating the amount of ethnicity to a recent birth in that location.  This logic is predicated on a whole lot of assumptions stacked on top of each other, like a house of cards. And we all know about assume.

23andMe, you should be ashamed of yourself for perpetrating genetic hogwash on your unsuspecting, believing and often vulnerable customers.  Climb down out of your ivory tower, buy a vowel and get a clue.  Statistics in an academic environment and reality sometimes just don’t mesh – and you, 23andMe, have the wherewithal and the customer base to discern the difference. You are supposed to be a science company.  You have no excuse.

I understand the desire to provide new tools to customers, but inaccurate simplicity is never a priority over realism.

I hope 23andMe will have the decency to remove this new deceptive and misleading “feature” that should never have made it past “proof of concept” in the first place.




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

Thank you so much.

DNA Purchases and Free Transfers

Genealogy Services

Genealogy Research

133 thoughts on “Calling HOGWASH on 23andMe’s Ancestry Timeline

  1. How is one able to confirm 64 great-great-great-great-grandparents and all the offspring were all faithful to their spouses?

    • Of course ethnicity doesn’t necessarily mean a person is born in a particular place. Many immigrants, esp early ones, settled in the same small isolated communities where they intermarried , often for several generations, so genetically later generations would appear to have the original ethnicity . This could screw the data used by the company to estimate origins. This is no doubt the cause of the inaccuracies re Eastern European ethnicity.
      My problem is a single probably illegitimate birth in London that coincides with a timeline for a 3% Swedish ancestry. Does this mean the father was Swedish or that the timeline is incorrect entirely and is from a much earlier period? I think that latter is probably more likely as DNA matches with similar estimates don’t show anything Scandinavian in their trees.

  2. Also, would you not have 1,024 great-great-great-great grandparents?

    Parents – 2
    Grand Parents – 4
    Great – 16
    GG – 64
    GGG – 256
    GGGG – 1,024

    • LOL- I know it is late at night, but you need to work your numbers again. It is X2 each generation. 4,8,16,32,64, etc.

      • You are correct. First step is great grandparents (8) and next steps are parents of grandparents.

        My second attempt messed up between 16 and 32.

        I’m curious to what year these six generations would date back to and if they even reach back to 1759’s Henry Bolton.

  3. Yeah, the 23andMe “ancestry timeline” is hilariously inaccurate. Mine tells me “you most likely had a parent or grandparent who was 100% British and Irish; this person was most likely born between 1920 and 1950” (which, nope; one great-great-grandfather, born in Ireland in 1845; one 3rd great-grandfather, born in Ireland in 1829; one 4th great-grandfather, born in England in 1795). And “you most likely had a great-grandparent. 2nd or 3rd great-grandparent who was 100% French and German; this person was most likely born between 1830 and 1890 (close in this case, 3rd great-grandfather, born circa 1806; son of the children of immigrants from the Palatinate); and then “you most likely had a 5th, 6th or 7th great-grandparent who was 100% Italian (which, nope, no Italian at all; this seems like it probably comes from the Palatine German/Bavarian/Swiss ancestry of the previously mentioned “100% German”).

  4. Do you have a dna service that you suggest if someone is wanting to test their ethnicity? I was looking into 23andme, but this is one of many negative reviews that I’ve seen

  5. I cried myself to sleep one night because of the 23andme timeline. Yes, it also made me question my parentage thinking my father may have been a British man, knowing full well that both sides of my family were from small mountain villages in Southern Italy and had been there for centuries. It was very misleading especially when the ethnicity moved over a generation with an update. Not happy with that feature. I do appreciate your article and these explanations. Thank you.

    • Less than 1% is probably more than 5 generation, but it’s hard to tell because of the nature of recombination.

      • I wonder why they bury it so deep in a white paper, but 23andMe explain well why the results of “how far back” are based on a mathematical model that makes some assumptions:
        “Model assumptions
        1. Ancestry Composition proportions and segment lengths capture the true levels of ancestry from each population.
        2. Each ancestry is introduce by a single ancestor g generations ago. Though obviously not the case for most complex admixture events (or for any ancestry inherited from both parents), this assumption allows for the simplification of statistical calculations.”
        The key phrase is “Though obviously not the case”. So this is why in many, many cases this is why the predictions are unrealistic.
        Endogamy of founders in frontier towns is the reality in North America. For me 0.2% turned out to be 12 generations ago. But what is the percentage made of is even more important : number and length of segments.

        But I understand Roberta that you may be tired of answering the same questions over and over…

        • Also, that inheritance isn’t 50% in every generation, but that’s the only model we can use. There are more variables too.

  6. So I got my results back and the timeline only shows 1st and 2nd generation (between 1920-1950). Nothing after that. The results claim I’m 99.99% British / Irish, which would make sense as that’s where I’m from as are my mother and father. However, my mothers family moved from Sicily to the UK. The test is utter b#llocks and 23&me offered no details as to why my ancestry only goes as far back as my mother and father.

Leave a Reply