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mariusz99
12-16-2025, 12:06 PM
I have a riddle.

My girlfriend shares 2% of her DNA with a Romani relative. MyHeritage shows shared DNA on 3 chromosomes. And indeed, all GEDmatch calculators (K13, K36, etc.) as well as the Humanitas report show Romani admixture on those same chromosomes (of course represented as Georgia and Iran, but the signal is obvious). What’s more, the Pomeranian ancestry she has from her grandmother also overlaps with matches from MyHeritage and GEDmatch.

In my case, however, it’s strange. On chromosome 3, K13 shows 30% Sweden for my grandmother, almost 100% for my mother, and about half of that for me. Chromosome 6 is textbook — grandmother 100% Sweden, mother 50%, me 30%. According to MyHeritage, chromosome 6 comes entirely from my mother’s side and fully from my grandmother, so that makes sense. K36 and Humanitas show the same thing.

The problem is chromosome 9. Before the Ancestry update, it was Germanic (Humanitas showed Germany there). But according to MyHeritage, I have almost nothing from my grandmother on that chromosome. Meanwhile, K36 does indeed show regions attributed to my grandfather on chromosome 9 (eastern/southern Poland). But in K13, my grandmother has 10% Sweden, my mother 50%, and I have 30% on chromosome 9.

On chromosome 17, I again have a lot of DNA inherited from my grandmother, and it shows Northern Europe there — in every calculator.

But what I don’t understand is this: supposedly it should work in such a way that if, for example, on chromosome 2 my grandmother has 50% Romani or German, then I should inherit that on chromosome 2 as well. And while in my girlfriend’s case this lines up nicely and clearly shows Romani ancestry, in my case it jumps between chromosomes. It’s not even about the file itself, because three different MyHeritage files show this nonsense.

For example, if Humanitas shows my grandmother as Lower Saxony on chromosome 12 and I don’t have that on chromosome 12, it suddenly pops up on chromosome 14 (it’s true that I used an Ancestry file for myself and a MyHeritage file for my grandmother, but still).


I’m hoping that some expert here will explain this to me. I’ve already seen things like this on Ancestry, where they first classified part of a chromosome as Jewish, then changed it to Slavic, and then back to German (how is that even possible???). I’d really like to understand this, because only then will I be able to analyze my grandfather’s side properly. And as I mentioned, in our family the Germanic DNA comes only from my grandmother. The entire rest of the family has exclusively Polish roots, and specifically from eastern Poland.

Wend-Kruzek
12-16-2025, 07:12 PM
tak toto asi nevysvetlí nikto , autosomalne DNA sa podľa mna dedí ako chce;) a kalkulacky to maju v...

Boudin
12-16-2025, 09:11 PM
\I’m hoping that some expert here will explain this to me.

Explanation: You think GEDmatch calculators / chromosome paintings are useful, but they're largely noise. You're seeing patterns in noise.

mariusz99
12-17-2025, 07:58 AM
Explanation: You think GEDmatch calculators / chromosome paintings are useful, but they're largely noise. You're seeing patterns in noise.

As for selected—emphasis on selected—GEDmatch calculators, I have repeatedly obtained better results from them for myself or for friends with well-defined ancestry than from commercial tests. Not to mention the fact that even ancestry as relatively “exotic” from a Polish perspective, and not in a distant line—such as Romani—was not shown by any commercial test. Perhaps only K13 and G25 did, but those are not GEDmatch.

The same applies to chromosome paintings: what I wrote above obviously shows inaccuracies and a lack of consistency, but still, in my opinion, they are often better than commercial tests. Maybe this is only true in my case? I don’t know. But if even MH (with all its flaws) is unable to sensibly show my grandmother’s German ancestry, which is close and well documented, and what Ancestry did to my chromosomes in the latest update (previously there was a Germanic chromosome, now it’s Baltic; elsewhere they changed Russian to southern Polish, and some Jewish segments are now gone altogether), then that is simply a scandal.

Against this background, GEDmatch doesn’t look that bad at all.

Boudin
12-17-2025, 09:24 PM
As for selected—emphasis on selected—GEDmatch calculators, I have repeatedly obtained better results from them for myself or for friends with well-defined ancestry than from commercial tests.

I'm firmly convinced if you shared the results you're speaking of and tried to make your case that GEDmatch was more accurate, you would realize before you finished writing the post that you were incorrect.

mariusz99
12-18-2025, 08:08 AM
I'm firmly convinced if you shared the results you're speaking of and tried to make your case that GEDmatch was more accurate, you would realize before you finished writing the post that you were incorrect.

If people I know have matches with relatives from specific regions (other than Poland), and these are matches confirmed in the genealogical tree—so they are indeed relatives—and even a simple calculator like K13 shows the same locations on the chromosomes, meaning the similarity matches what MyHeritage shows and aligns with the ethnicity assigned there, then this is accurate.

The only issue is that those people only have MyHeritage, and I don’t know how it would look if they had Ancestry or 23andMe.

However, based on myself and my family, I see that Ancestry does such nonsense on the chromosomes that it cannot be taken seriously.

Peterski
12-22-2025, 09:06 PM
Well you inherited DNA directly from your mother only, not from your grandmother. DNA from your grandmother was inherited by your mother and then by you but indirectly. Some segments could be lost during genetic recombination either between your grandmother and your mother, or later between your mother and you. In my opinion it would make sense only to compare your grandmother to your mother, and then your mother to you. It doesn't make sense to compare your grandmother directly to you. Maybe your mother inherited Lower Saxony on chromosome 12, but it was lost during recombination and you didn't inherit it.

How much of Lower Saxony does your mother score on chromosome 12?

PS:

I sent you an email about updated DNA Origin.