DNA tests and their accuracy

[princeton90]

I heard some speculations that the DNA tests might not give very accurate results for ethnicity estimation. I mean, it is speculated those tests sometimes miss some significant part of your ancestry or identify some part of your ancestry incorrectly. Is there any truth in it?

[Lemminkäinen]

It is true, because many tests are done following the makers' expectations. Test makers always make definitions about references and the data. Although we usually see references and they are fairly listed, we don't see how the data is cropped. In many cases even the testers are not aware of it, but still allege the test being credible. Commersial players make this knowingly.

[JamesBond007]

It seems to me the mainstream ones are all trash and try to pander to your preconceived notions you have about who you are. Let us be clear no one is 3 or more ethnicities. Let us say someone is French then they could be broken down into about 3 or 4 constituent parts (ethnicities) and same is true for the British. Now , of course imagine an Amerimutt you begin to see the problem.


This was the real deal , I have no idea why people stopped going down this path, by including more academic sources, over the years etc... and the only reason why it is the 'real deal' is because knowing your true ancestry is a step in the direction of knowing your chances of contracting certain diseases :

http://genetics.cs.ucla.edu/spa/


If it was not for the latter reason then the politically correct forces would make this all out to be non-reliable pseudo-science saying we are all one race the 'human race' kumbaya bullshit :


my results :

https://i.postimg.cc/28Rh43dJ/me.png

Are the results exciting ? No ! . Are the results entertaining ? No !. Are they the truth ? Roughly , within 500 KMS I would say I'm more Western shifted than that but whatever

[princeton90]

It seems to me the mainstream ones are all trash and try to pander to your preconceived notions you have about who you are. Let us be clear no one is 3 or more ethnicities. Let us say someone is French then they could be broken down into about 3 or 4 constituent parts (ethnicities) and same is true for the British. Now , of course imagine an Amerimutt you begin to see the problem.


This was the real deal , I have no idea why people stopped going down this path, by including more academic sources, over the years etc... and the only reason why it is the 'real deal' is because knowing your true ancestry is a step in the direction of knowing your chances of contracting certain diseases :

http://genetics.cs.ucla.edu/spa/


If it was not for the latter reason then the politically correct forces would make this all out to be non-reliable pseudo-science saying we are all one race the 'human race' kumbaya bullshit :


my results :


Are the results exciting ? No ! . Are the results entertaining ? No !. Are they the truth ? Roughly , within 500 KMS I would say I'm more Western shifted than that but whatever

I think I got your point. If those tests gave just one or two regions as ancestral estimation, the tests wouldn't be so exciting at all and maybe most test-takers wouldn't decide to take the test.

[Chris596]

These are all the commercial DNA tests I've done over 1 year. The only sure thing is that the majority of my ancestry is from the Balkans and Eastern Europe and the Jewish. The rest is always nonsense / random stuff. You be the judge.

https://i.imgur.com/vqNxRv9.png

Oh and I forgot about LivingDNA, which told me this after a free upload: 95% Europe, 5% Middle East

[Lemminkäinen]

Of course all commercial test makers are cautious of making wrong disease or carrier gene results, because American an European laws could hit hardly, but ancestry is a wild west.

[Lemminkäinen]

These are all the commercial DNA tests I've done over 1 year. The only sure thing is that the majority of my ancestry is from the Balkans and Eastern Europe and the Jewish. The rest is always nonsense / random stuff. You be the judge.

https://i.imgur.com/vqNxRv9.png

Oh and I forgot about LivingDNA, which told me this after a free upload: 95% Europe, 5% Middle East

Small proportions are due to overfitting. All "oracles" suffer from it less or more.

[Chris596]

I think I got your point. If those tests gave just one or two regions as ancestral estimation, the tests wouldn't be so exciting at all and maybe most test-takers wouldn't decide to take the test.

Well I have to disagree here because in my case most tests give me only one, maybe two ancestral regions and that's it. Because I'm really not that mixed compared to many people. For example Myheritage and 23andme only shows Romania as my ancestral place and that's it (they are right because my father is from Romania).

And the ancestry report of Myheritage shows me Balkan (which is true) and Scandinavia (not true at all), these two regions and the Jewish which is not a region of course. The best report still comes from 23andme in my case, which shows Balkan and Eastern Europe (as I've told you, my father is from Romania - Balkans, and my mother is from Hungary - Eastern Europe) + the Jewish. So I think they are really trying to be accurate, because you can see I'm not that mixed and they really show me just one or two regions, but none of these tests can tell you the full truth, this is my perception.

Ethnically I'm Hungarian, compare me to other Hungarians who score Eastern Europe, Balkans, Italy, Germany, British/Irish, Scandinavian, Finnish, etc. all of these together on 23andme or similar tests. So you will see what I'm talking about.

[RatCat]

I think I got your point. If those tests gave just one or two regions as ancestral estimation, the tests wouldn't be so exciting at all and maybe most test-takers wouldn't decide to take the test.

That's not always the case. My results got 1 region and it says %100 Caucasus.

[Ylla]

Inaccurate from my experience. Each company tells you something different based on their references. It hasn't answered some questions regarding my maternal ancestry.

[princeton90]

Well I have to disagree here because in my case most tests give me only one, maybe two ancestral regions and that's it. Because I'm really not that mixed compared to many people. For example Myheritage and 23andme only shows Romania as my ancestral place and that's it (they are right because my father is from Romania).

And the ancestry report of Myheritage shows me Balkan (which is true) and Scandinavia (not true at all), these two regions and the Jewish which is not a region of course. The best report still comes from 23andme in my case, which shows Balkan and Eastern Europe (as I've told you, my father is from Romania - Balkans, and my mother is from Hungary - Eastern Europe) + the Jewish. So I think they are really trying to be accurate, because you can see I'm not that mixed and they really show me just one or two regions, but none of these tests can tell you the full truth, this is my perception.

Ethnically I'm Hungarian, compare me to other Hungarians who score Eastern Europe, Balkans, Italy, Germany, British/Irish, Scandinavian, Finnish, etc. all of these together on 23andme or similar tests. So you will see what I'm talking about.


That's not always the case. My results got 1 region and it says %100 Caucasus.

Years ago, I had seen DNA results of a person who is half Turkish and half Arabian descent. However, his results were almost purely Turkish as he clustered with Turkish samples on GEDMatch-Oracle. He and some other Redditors claimed the DNA test "missed" his Arabian part. It seems a bit unusual but I couldn't be sure.

[gixajo]

That's not always the case. My results got 1 region and it says %100 Caucasus.

https://i.imgur.com/55WT7gQ.png

[Chris596]

Years ago, I had seen DNA results of a person who is half Turkish and half Arabian descent. However, his results were almost purely Turkish as he clustered with Turkish samples on GEDMatch Oracle. He and some other Redditors claimed the DNA test "missed" his Arabian part. It seems a bit unusual but I couldn't be sure.

Right, that also makes sense. As you can see, my results are really boring and ethnically I'm Hungarian and I cluster with Serbs, Romanians, Bosniaks, Croats, etc. all Balkan ethnicities. So who is really a Hungarian? Someone who is half German? Someone who is 10% Italian? Someone who is 70% Balkan? Someone who is 45% Eastern European?

This is why this question is irrelevant in my opinion. Hungarians are very, very far away from being as homogeneous as Germans, the British, French, etc. I always felt Hungarian and nothing else. And perhaps I'm nothing else than a Hungarian, really.

[gixajo]

They are as precise as they can be right now, what they cannot be is infallible.

[RatCat]

Years ago, I had seen DNA results of a person who is half Turkish and half Arabian descent. However, his results were almost purely Turkish as he clustered with Turkish samples on GEDMatch Oracle. He and some other Redditors claimed the DNA test "missed" his Arabian part. It seems a bit unusual but I couldn't be sure.

I think it's impossible to miss %50 of your dna, if he had some Arabian it would show up, even some dudes who dont have any Arab ancestors sometimes get some "Arab" on their results.

And i think His distance would be very high to cluster with Turkish samples on gedmatch but maybe he can get Turkish as his first result on oracle. If you ask me either He is not %50 Arab or He is trolling. If he is half arab from countries close to Turkey maybe He can get Turkish as first result on some oracles but his distance would be very high. For example you can see my results on my signature and on 1 population oracles i get Georgian or Abkhazian as a first result but my distance is 6-10 depends on the calculator, That doesn't mean i am purely Abkhazian or Georgian. That means genetically I'm more close to Abkhazians or Georgians than to other populations, that doesn't mean I'm pretty close to them neither. The distance you get is important.

[Scandal]

Right, that also makes sense. As you can see, my results are really boring and ethnically I'm Hungarian and I cluster with Serbs, Romanians, Bosniaks, Croats, etc. all Balkan ethnicities. So who is really a Hungarian? Someone who is half German? Someone who is 10% Italian? Someone who is 70% Balkan? Someone who is 45% Eastern European?

This is why this question is irrelevant in my opinion. Hungarians are very, very far away from being as homogeneous as Germans, the British, French, etc. I always felt Hungarian and nothing else. And perhaps I'm nothing else than a Hungarian, really.

Every member of an ethnicity isn't supposed to plot in exactly the same place. All ethnicities have a range.
Germans being less diverse than hungarians is debatable when it comes to genetics. On k13 North Germans get lower distances to Scandinavians than to South Germany.

[princeton90]

I think it's impossible to miss %50 of your dna, if he had some Arabian it would show up, even some dudes who dont have any Arab ancestors sometimes get some "Arab" on their results.

And i think His distance would be very high to cluster with Turkish samples on gedmatch but maybe he can get Turkish as his first result on oracle. If you ask me either He is not %50 Arab or He is trolling. If he is half arab from countries close to Turkey maybe He can get Turkish as first result on some oracles but his distance would be very high. For example you can see my results on my signature and on 1 population oracles i get Georgian or Abkhazian as a first result but my distance is 6-10 depends on the calculator, That doesn't mean i am purely Abkhazian or Georgian. That means genetically I'm more close to Abkhazians or Georgians than to other populations, that doesn't mean I'm pretty close to them neither. The distance you get is important.

His distance to Turkish samples was about 5% if I remember correctly.

[Zoro]

First and foremost they should replace the word ANCESTRY with SIMILARITY since I've been told by EurasianDNA that it's very difficult to determine which direction the genes flowed and it takes very sophisticated tests and plenty of time to get a handle on actual geneflow or ancestry.

So if European gets 2% American Indian they should say SIMILAR TO.

The other thing is percentages will vary all over the place depending on what components you have.

For example if you are a European and the calculator has 10 different European components then all your DNA will be eaten up all those components and some may even be redundant or similar to other components. So if you do try to figure out your E. Asian pecentage there's no chance because all your DNA has already been eaten up by those numerous components.