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Erik
09-21-2014, 02:16 AM
I had a thought today that I could potentially test out, but first I was curious if anyone knew anything about this.

If I made up a fake twin on Ancestry.com named "Erik2" and then ordered another AncestryDNA kit and sent in the results under "Erik2", is it a possibility that the results could be slightly different?

La Papallona
09-21-2014, 02:36 AM
Possibly, if there is any difference it's probably very little.

Táltos
09-21-2014, 02:50 AM
I had a thought today that I could potentially test out, but first I was curious if anyone knew anything about this.

If I made up a fake twin on Ancestry.com named "Erik2" and then ordered another AncestryDNA kit and sent in the results under "Erik2", is it a possibility that the results could be slightly different?
Sure. Someone over at 23andme reported that they did just that. Apparently his results came back slightly different, percentage wise, but it sounded like he had the same basic breakdown of groups. He also indicated that the two kits showed slightly different results on Gedmatch. He is an identical twin to himself, in his matches. :)

You can read about it here, but will need to sign in. https://www.23andme.com/you/community/thread/29017/

rod
09-21-2014, 04:40 AM
I did the same thing and here is the comparison I made when I received my 2nd test results in August.

Old test (21 March 2013):

Total autosomal (Chr 1-22): 0.093 % ( 637 of 682549 SNPs) are NoCalls
Total autosomal (Chr 1-22): 29.646 % (202347 of 682549 SNPs) are Heterozygous (this tally excludes 0 heterozygous SNPs that were treated as homozygous)
Total autosomal (Chr 1-22): 70.354 % (480202 of 682549 SNPs) are Homozygous (this tally includes 0 heterozygous SNPs that were treated as homozygous)

Ethnicity
Europe 100%
Scandinavia 35%
Great Britain 30%
Ireland 16%
Iberian Peninsula 9%
Europe West 7%
Europe East 1%
European Jewish 1%
Italy/Greece < 1%


New test (12 August 2014):

Total autosomal (Chr 1-22): 1.680 % ( 11466 of 682549 SNPs) are NoCalls
Total autosomal (Chr 1-22): 29.190 % (199239 of 682549 SNPs) are Heterozygous (this tally excludes 0 heterozygous SNPs that were treated as homozygous)
Total autosomal (Chr 1-22): 70.810 % (483310 of 682549 SNPs) are Homozygous (this tally includes 0 heterozygous SNPs that were treated as homozygous)

Ethnicity
Europe 100%
Scandinavia 40%
Great Britain 22%
Ireland 19%
Iberian Peninsula 9%
Europe West 7%
Europe East 1%
European Jewish 1%
Italy/Greece < 1%

Also, if they're using the "phased" results, 71,259 SNPs have the "parents" reversed.

The twin who tested in 2013 has 9638 matches.
The twin who tested in 2014 has 9467 matches.
The numbers look close but the twins only have 6366 (about 66%-67%) matches in common. The rest only match one of "us".

Only one significant relationship change occurred - a 3rd cousin 1 removed changed from a predicted 96% 4th cousin to a predicted 98% 3rd cousin. His son remained in the moderate 5th-8th range.

Both twins have the same 98% confidence predicted 3rd cousin who is a 4th cousin 2 removed. The 2014 twin has a hint attached to this person but the 2013 twin in the same tree doesn't have a hint.

ZephyrousMandaru
09-21-2014, 04:56 AM
Yes, because the number of SNPs being genotyped vary, DNA testing companies never evenly analyze every facet of your chromosomes, with the same level of coverage. I've tested with 23andMe and AncestryDNA, and when I compare the results from both sets of raw data, my results differed, but only marginally.

Rick
11-11-2014, 11:51 PM
I will have an interesting comparison soon. Two of my sisters, unbeknownst to each other, ordered the ancestry dna test. One has received her results, while the other still waits. I'm very curious to see how different the ethnicity estimates are. I may have mine done just to have a 3rd sample. I'll post the comparative results when my 2nd sis gets her results, in case anyone is interested in just how widely ancestry.com ethnicity estimates may vary within a sibling set.

Erik
06-19-2015, 06:08 PM
I will have an interesting comparison soon. Two of my sisters, unbeknownst to each other, ordered the ancestry dna test. One has received her results, while the other still waits. I'm very curious to see how different the ethnicity estimates are. I may have mine done just to have a 3rd sample. I'll post the comparative results when my 2nd sis gets her results, in case anyone is interested in just how widely ancestry.com ethnicity estimates may vary within a sibling set.

Did you get these results yet?

Rick
06-20-2015, 02:38 PM
I had forgotten about this. Thanks for the reminder. I have one sister's ancestry results and my family finder results. Never received my other sister's results, but I've just sent her a note. I'll update this when I get those, but for now here is the first 2-way comparison.

Me (ftdna family finder)
European 100%
Western and Central Europe. 51%
British Isles 45%
Scandinavia 4%

Sister 1 (DNA.ancestry
Europe 100%
Europe West 66%
Great Britain 21%
Ireland 6%
Iberian pen. 3%
Scandinavia 3%
Italy/Greece < 1%

Different test companies, so difficult to say how much of the difference is down to different tests and definitions of regions. My other sister tested with ancestry too, so that will be a good 2-way comparison with sister 1.

I will update with the 3rd set of results.
cheers,
Rick