Is 0.1% or 0.2% Ethnicity Legit or Not? (percentage, population, Polish, African)

[Fisherman99]

Just took 23andme...results as follows (mostly as expected).



I'm viewing any ethnicity percentage of 1% or more as legit here and anything less (tenths of percentages) as background noise.


Thoughts?






99.8% European (Breakdown as Follows)

50.4% Polish
21.6% English
16.7% German
5.3% Broadly Northwest European
2.2% Broadly European
2.0% Italian
1.2% Spain/Portugal

0.2% Scandinavian
0.2% Broadly Southern European
0.1% Sub Saharan African
0.1% Unassigned
_________________
100% Total

[PA2UK]

It's impossible to say - sometimes it is, sometimes it isn't. Even amounts above 1% can be noise, and amounts under 1% may not be noise. There is no way to know for sure unless you can confirm it in your tree.

[Natnasci]

There is a great CBC show called Marketplace. They investigate all sorts of things. This one is about genetic testing. Watch it. It is quiet surprising.


https://www.youtube.com/watch?v=Isa5c1p6aC0

[SunGrins]

It depends. If it survives the next ethnicity update that comes out it probably is real. I have a micro percentage of Ashkenazi that sticks with me over a couple changes so I guess it's real. I had a similar percentage of Danish that went away even though I have some Danish ancestry about six generations ago. It's a crap shoot with these tiny ethnicities.

[Mircea]

Originally Posted by Fisherman99

I'm viewing any ethnicity percentage of 1% or more as legit here and anything less (tenths of percentages) as background noise.

Thoughts?

I think you might have trouble with math. From your 6th Grade studies, what's half of 100%?

50%. And half of that?

25%. And half of that?

12.5%. Half of that is 6.25%. Half of that is 3.12%. Half of that is 1.5% and then 0.7%.

See how that works? That's about 7 generations.

If you're seeing less than 1% it's about 7-8 generations back.

7 Generations is 128 grand-parents and 8 Generations is 256 grand-parents.

Anyone of them can produce what you call "noise."

[PA2UK]

Originally Posted by Mircea

I think you might have trouble with math. From your 6th Grade studies, what's half of 100%?

50%. And half of that?

25%. And half of that?

12.5%. Half of that is 6.25%. Half of that is 3.12%. Half of that is 1.5% and then 0.7%.

See how that works? That's about 7 generations.

If you're seeing less than 1% it's about 7-8 generations back.

7 Generations is 128 grand-parents and 8 Generations is 256 grand-parents.

Anyone of them can produce what you call "noise."

Except we don't get exactly those amounts from each ancestor. While we all get 50% from each parent, we do not necessarily get 25% from each grandparent, or 12.5% from each great grandparent, etc.

His question was a valid one so there's no need to be condescending, unfortunately it's just not a question with a solid answer. And I'm not really sure what your point is - "noise" is like a false positive, so it's not really something we inherit directly from one single ancestor anyway. It's more like a recombination of DNA we probably got from multiple ancestors that randomly happens to match a population you actually have no ancestry from.