Different DNA Test, Different Results

[Will Stevenson]

What is going on. I have very different DNA result for all 3 companies that I have used. This is now making my doubt this whole DNA thing. Can someone please try and explain to me what is going on ? Here are my results.
Thanks.

My Family Tree (Autosomal) DNA came out as 99% British.

I also did Ancestry and my DNA and results were,
Great Britain 39%
Scandinavia 26%
Europe West 13%
Ireland 9%
Iberian Peninsula 8%
Low Confidence Region
Finland/Northwest Russia 2%
Europe East 1%
Italy/Greece 1%

Then there are my 23 and Me Results. Different again
British & Irish
55.3%
Scandinavian
11.8%
French & German
10.8%
Broadly Northwestern European
21.2%
Eastern European
0.8%
Sub-Saharan African
< 0.1%
Middle Eastern & North African
< 0.1%

[davidft]

What you have discovered is what we all find out eventually and that is that DNA cannot give you your ethnic inheritance. What these DNA testing companies give you is their best guess based on the algorithms they use and their sometimes very small sample populations on which they base their definitions of one ethnicity or another.

Of course it gets better as periodically the companies recalculate ethnicities and you can suddenly find your alleged ethnicity changes significantly.

The truth is the science is no where near as advanced as it needs to be to make the claims the companies are making. They are in short snake oil companies selling near worthless products to the gullible. That said I still think its worth testing as you get an idea and maybe even a surprise or two and the accumulating collection of tests results may lead to better predictions in the future but in the meantime these ethnicity DNA results should just be treated as a bit of fun and not taken at all seriously.

This is just my personal view so anyone please do not be offended if you do not agree with it

[Will Stevenson]

Thanks David. All opinions are important. 

[ThrelfallYorky]

The different results don't surprise me.
In any case, knowing "your" DNA profile is not really all that helpful with tracing your own direct ancestry -
- but it's a nice, not-so-little earner!

[DevonCruwys]

Each company uses different algorithms and different reference populations. They also cover different time periods. Most people do get very different results from each company. These admixture reports are a bonus feature. The main reason for testing is to get the DNA matches.

I wrote a blog post comparing my results and I included links to various resources for further reading:

https://cruwys.blogspot.co.uk/2015/05/comparing-admixture-results-from.html

[JaneyH_104]

Thanks for this, and especially for the link to Debbie's blog.  I've just done an autosomal test with Ancestry so while I wait for the results I thought I'd do some reading on the subject. 

While I'm more interested in cousin matches and finding people who are researching the same ancestors the ethnic inheritance question is also interesting.  Like Debbie my documented roots are very English - 31/32 of my 3x great grandparents were born in England with the remaining one born in Wales.  On branches where I've gone back further everyone has been born in England.  It'll be interesting what Ancestry tell my about my ethnic inheritance!

[Mart 'n' Al]

I think I've just saved some money...just when I was getting almost on the part-way road to maybe getting perhaps tested.  Possibly.

Martin

[J.J.]

  While I think it is great if people want to do this for themselves, it seems expensive and also rather unsettling that someone in an official status (or not)... might one day be able to demand or even buy these results and have my DNA.
  A few distant cousins have found me because they have the DNA of other cousins who have already contacted me...but truthfully, more contacts have been made from being right here on Rootschat or from other online information.  J.J.

[bwcw]

Thanx for this post, i was thinking of getting mine done but hesitated for these same reasons, looks like the companies just want our money. Don't think i will bother now.