Ancestry.com has just completed a major update to its DNA bio-ancestry predictions that has broken down European countries into many smaller areas. They have added 68 locales, mainly in Europe. French Canadians are no longer listed as France, now they are either Quebec or Acadia. They have also made four jewish groups from one: Central and Eastern Ashkenazi plus North African and East Mediterranean Sephardic. Almost all my Jewish friends have no Sephardic listed, giving the lie to some family stories. There are some interesting new categories like Germans in Russia and one combining both sides of the English Channel into a new category called Southeastern England & Northwestern Europe.

I am enjoying looking at the updated origins of many of the people I have helped. On the next page I will show images of the more interesting mixtures. Here is a classic North European mix of a Tenneseean with colonial roots.

I do recommmend scrolling down and clicking on the link to what has changed. Below is the image of how the predictions for our Tennesseean are different from last year. Notice that Germany has gone from 21% to 2%. Some of that must now be Denmark and some SE England & NW Europe.

While 1-2% could be a 4th or 5th grandparent, it could also be just noise or too far back to find. I have often told people not to worry about a 1% call as it is too small to be sure of. In my own case, I lost my 1% Finnish, which I actually thought was accurate because its location matches one of the two where my Norwegian American dad has Finnish, according to 23andme. Additionally, 23andme has my brother matching the other location. We have yet to find that Finnish 4th or further back grandparent, but we do match many Finnish people on those segments over at GEDmatch. Perhaps they just have some Norwegian. More on that in another blog post.

To quote my own blog post from 2020 comparing the origin predictions at each company “predicting the ethnicity for people of Northern European heritage like my brother and myself, is very hard to do accurately because there was so much mixing of those populations.” The book “Who We Are and How We Got Here” by geneticist David Reich makes that point well and goes into the details of what ancient DNA teaches us about European migrations and mixtures.

I found the explanatory Ancestry white paper (click here to read it) hard to understand, so I enlisted two different AI platforms to summarize it for me. A fun use of this technology. To be fair, after the quite technical many paragraph summary ChatGPT gave me, I wised up and asked Claude to summarize it in plain English. That went better. Here are a few take aways:

Scroll down to move on to the origin images if you prefer not to slog through these explanations.

From ChatGPT after many many good but highly technical paragraphs:

Take‑Home Points

• AncestryDNA’s 2025 release markedly increases the granularity (146 regions) and refines the inference algorithm to improve accuracy.
• The method combines phasing, haplotype modeling, and a Hidden Markov Model to assign bits of each person’s genome to ancestral regions.
• The reference panels are carefully constructed from a mix of customer data and public datasets, with rigorous filtering to avoid admixture noise.
• Validation indicates generally strong performance, especially for reasonably large assignments (above 5 %), though precision varies across regions.
• The white paper is transparent about uncertainty, limitations, and the ongoing nature of improvement.

Now an excerpt from Claude‘s plain English summary:

The Basic Idea
Your DNA is like a patchwork quilt made up of pieces from different ancestral populations. AncestryDNA compares your DNA to reference groups of people whose ancestors have lived in specific places for many generations. By finding which reference groups you match best, they can estimate what percentage of your ancestry comes from different regions.
[… stuff removed …]

How Accurate Is It?
They test their model using several approaches:

• Simulated data: Creating fake DNA profiles from known ancestral combinations and seeing if their algorithm gets it right
• Single-origin individuals: Testing on people known to be from one place
• Family tree validation: Checking results against people who have all grandparents from the same country

Generally, their accuracy is quite good; when they predict a region above 5%, they’re usually correct, though some neighboring regions can be harder to distinguish (like different parts of England or Ireland).

The Bottom Line
AncestryDNA’s approach combines massive amounts of customer DNA data, sophisticated algorithms, and careful validation to estimate where your ancestors came from. While not perfect, it’s generally accurate for major ancestral components, though it can struggle with distinguishing between genetically similar neighboring regions.

Before we look at the images of the updated origins of some of the more interesting ad-mixed people I have worked with, here is my own family.

My Norwegian side is known to be from Southern Norway: Hordaland, the Agders, and the Drammen area. The journeys feature of Origins at Ancestry shows those details nicely, plus you can learn the history that surrounded and shaped your ancestors using the Timeline feature. There have been almost no changes to the Ancestry Composition of us Nordic peoples. Here is my perfect cousin who I featured in a past post as the only family member who got 100% Scandinavian

My German side is half Jewish and half Bavarian but appears to have a few roots further East. Here are my brother’s results. Notice that, unlike me, he has kept that tiny Finnish amount

Now for a few more unusual results:

Here are the regions for two unknown father cases where the mother’s origins were colonial American while in one case the father was Mexican and in the other case he was Hispanic with deep roots in New Mexico. Can you tell which is which? The answer is below both images.

One thing to notice is that they both have a sprinkling of Jewish. That is because many jews “converted” and then emigrated to the New World where they often continued to practice their faith in secret. Click here for the wikipedia article about that. They both have Spanish, Portuguese, Canary Islands, and indigenous American.

Number 1 is Mexican. They are very similar. Typically New Mexican will have more Jewish and no African plus some American indigenous. Both will have Mexican indigenous although Mexican may have more plus some Yucatan.

Here are a few more fun ones; both cases are unknown fathers with mothers of primarily British Isles origin. See if you have any thoughts about this one. Click here for the blog post which ends with her unknown father search.

Thoughts on this next one? Click here for the blog post about her unknown father search.

Have fun expoloring the new bio-ancestry estimates at Ancestry. Well this has been a much longer post than usual. Please note that many of the tools mentioned in the posts for these cases are no longer available. However the sheer number of DNA testers make these searches very possible without special tools. I wonder how soon AI can be harnessed for that task?