Ancestry DNA: German great-grandfather, no German in 'ethnicity breakdown'?

[Matt62]

I have a German great-great-great grandfather (from Vorpommern in northern Germany, around the Baltic Sea area).

Given the relative distance, I was not expecting to find much trace of this in the Ancestry DNA / FTDNA / MyHeritage ethnicity estimate, because on average a person derives 3% of their genes from a 3x great-grandparent.

In fact, no 'German' surfaced in my ethnicity map - I was 85% Irish / Scottish and 15% 'England, Wales and Northwestern Europe' on Ancestry DNA; 95% British Isles, 3% Scandinavian and 2% East Europe on FTDNA, whilst on MyHeritage the breakdown was 95% Irish, Scottish, and Welsh and 5% Scandinavian.

I didn't really think about this...until I tested an older relative who is the great-grandchild of this German Pomeranian ancestor. Now, a great-grandchild typically receives 12.5% from a great-grandfather (give or take a bit with random recombination) - yet this older relative, who is much closer genetically to the German heritage than myself, also had no 'German' showing anywhere in his ethnicity breakdown.

Instead, on Ancestry DNA (the only one he's tested with thus far) he was 91% Irish and Scottish and 8% England, Wales and Northwestern Europe, with the only other element being a very small 1% European Jewish.

I have read that AncestryDNA actually has a 'Pomerania' genetic community cluster and I find it rather suspect that even someone as closely related as a great-grandchild would apparently evidence none of this ancestor's ethnicity in his estimate.

Are the Pomeranian German genes being grouped under another category, such as 'England, Wales & NE'? Is there any other reason why the estimate would not include it at all?

[Ruskie]

Everyone advises not to take much notice of ethnicity results. They are likely to change as more people take DNA tests.

I only glanced at this so don’t know if it will help:
https://www.ancestrycdn.com/dna/static/pdf/whitepapers/EV2019_white_paper.pdf

Perhaps your German ancestor’s ancestors came from elsewhere.

[davidft]

In my opinion you are putting too much faith in the "science" behind these ethnicity estimates because it is for the most part not science but assumption, inference and wishful thinking.

Having tested with a number of firms you have seen how these estimates can differ from one tester to another, indeed there is a thread on here where people in the past detailed their ethnicity breakdowns and how they differed from one tester to another. You will also know that these firms update their estimates from time to time i.e. what they say about your ethnicity today is not necessarily what they will say tomorrow.

You grievance seems to be that you have no German ethnicity showing and yet you admit yourself that the most DNA you would expect to have inherited from the ancestor in question is 3 percent. This brings up two points, first 3% is well within the margin of error, and second just because you have identified an ancestor as coming from Germany doesn't mean his ancestry further back is German and therefore neither is he ethnicity wise.

If its any consolation I have tested with most of the DNA testing firms and they all give different results. I recently had an update from Living DNA and I have gone, according to them, from 100% Great Britain and Ireland to 96.8% Great Britain and Ireland and 3.2% Europe (North and West). Why not test with them they may find your elusive Germanic ethnicity

[melba_schmelba]

The simple fact is they do not have enough samples from Germany vs samples from the British Isles. Given the ancestry of the Anglo-Saxons came from northern Germany-southern Denmark-north Netherlands, Ancestry's algorithm just sees these populations as 'English' because that is its closest guess based on its British samples. If they did a more in depth study , or acquired one, such as the Irish DNA Atlas data, which Ancestry has likely acquired, they would be able to be more accurate. A similar problem exists with France as commercial DNA testing is banned there so Ancestry has very little French (or French descended) testers combined with substantial tree data to use as samples.
   But it can also be a problem for small percentages which I believe Ancestry tends to, on the basis of caution filter out as potential noise vs other companies such as 23andme or LivingDNA which actually give you the option to change the confidence level.

[Mart 'n' Al]

I will highlight Ruskie's valuable words,

"Perhaps your German ancestor’s ancestors came from elsewhere."

And David's,

"... just because you have identified an ancestor as coming from Germany doesn't mean his ancestry further back is German and therefore neither is he ethnicity wise."

Martin

[Carmella]

Another option:

If the German 3xGt Grandfather is on your direct paternal line (father to father to father) - then doing a Y-DNA test would give you a haplogroup with a geographical origin.

Y-DNA is more expensive, but it is more specific.  Its only through Y-DNA that I discovered I have a German/Polish paternal line.  Autosomal ethnicity estimates have not helped me, but Y-DNA has!

This might be worth a read:
https://dna-explained.com/2020/01/02/y-dna-part-1-overview/   

[ke]

The 50% of DNA you inherit from each parent in each subsequent generation is random, you just may not have inherited autosomal DNA from that line.

I have lots of ancestors I haven't inherited DNA from, the other 50%.