U.S. CitiesCity-Data Forum Index
Go Back   City-Data Forum > General Forums > Genealogy
 [Register]
Please register to participate in our discussions with 2 million other members - it's free and quick! Some forums can only be seen by registered members. After you create your account, you'll be able to customize options and access all our 15,000 new posts/day with fewer ads.
View detailed profile (Advanced) or search
site with Google Custom Search

Search Forums  (Advanced)
Reply Start New Thread
 
Old 03-31-2016, 12:40 PM
 
2 posts, read 6,767 times
Reputation: 10

Advertisements

I'm very new at this DNA thing. My main interest was to find out if I had any Ashkenazim Jewish heritage. My Ancestry.com results gave me a <1% Ashkenazi but when I ran my raw DNA results through GEDmatch's Jtest I got a 4.12 Ashkenazi result.

Is one test more accurate than the other? Are results that low even credible or are they a possible margin of error in general?

Can anyone enlighten me?

Script Girl
Reply With Quote Quick reply to this message

 
Old 03-31-2016, 01:17 PM
 
Location: Colorado (PA at heart)
8,216 posts, read 12,800,785 times
Reputation: 10446
There is a margin of error, but it's difficult to say any one is more accurate than the other. It just depends on the sample groups and how your DNA matches up with them. Different tests have different sample groups which means your results will be different. Gedmatch's different calculators in particular are often heavy weighted for one group or another. My understanding is that Jtest was specifically designed for European Jewish ancestry, so for someone with no Jewish heritage, it could be showing inflated results for Ashkenzai.

There is no DNA which is totally unique to any one region or group in Europe (the Jewish are the most genetically unique of Europe but they are still not 100% unique), and so all ethnicity tests are only an estimate. I would not take them too literally, especially results in very small amounts, unless you have a paper trail to back them up.
Reply With Quote Quick reply to this message
 
Old 03-31-2016, 01:32 PM
 
Location: Georgia, USA
21,481 posts, read 26,078,274 times
Reputation: 26426
Different sites come up with different percentages because they use different people to compare your DNA to. There is indeed a margin of error. The Ancestry.com number would be in the range of signal noise; GEDmatch looks more like a real finding.

Fun story here. See the "switched at birth" article:

Your Genetic Genealogist

If finances allow, you might want to test with 23AndMe, too.

Also, tracing your genealogical paper trail can find Jewish ancestors, and you can look for DNA matches who are known to be Jewish at Ancestry.com and GEDmatch.
Reply With Quote Quick reply to this message
 
Old 04-01-2016, 01:59 PM
 
629 posts, read 597,721 times
Reputation: 938
Definitely do BOTH tests.
Reply With Quote Quick reply to this message
 
Old 04-03-2016, 06:08 AM
 
2 posts, read 6,767 times
Reputation: 10
Thank you for taking time to respond - PA2Uk.

Suzi. I agree with you that GEDmatch looks like more of the real thing. On their individual breakdown, all but 6 of my 22 chromosomes had Ashkenazi bits on them. You can see the pic at the link below.



Not sure if that really means anything, but I was encouraged.

Manhattan Girl - I think I will do the other tests and compare.

Thank you all for responding!!

Script Girl
Reply With Quote Quick reply to this message
 
Old 03-13-2018, 09:49 AM
 
5 posts, read 4,571 times
Reputation: 11
Default What became of this?

Hey! I am eagerly following this thread because it is literally EXACTLY the same situation I am in. Can you please share a followup?
Reply With Quote Quick reply to this message
 
Old 03-13-2018, 11:37 AM
AFP
 
6,063 posts, read 3,622,558 times
Reputation: 5235
Quote:
Originally Posted by Scriptgirl View Post
Thank you for taking time to respond - PA2Uk.

Suzi. I agree with you that GEDmatch looks like more of the real thing. On their individual breakdown, all but 6 of my 22 chromosomes had Ashkenazi bits on them. You can see the pic at the link below.



Not sure if that really means anything, but I was encouraged.

Manhattan Girl - I think I will do the other tests and compare.

Thank you all for responding!!

Script Girl
I don't have any known Jewish ancestors within the last 400 years and am of Portuguese ancestry these are my Jtest results.
Attached Thumbnails
Ancestry VS Gedmatch-j-test.png  
Reply With Quote Quick reply to this message
 
Old 03-13-2018, 02:23 PM
 
Location: Cumberland
4,558 posts, read 7,617,865 times
Reputation: 2769
I learned through Ancestry.com that I have a great-great grandfather who was a Lithuanian Jewish immigrant. Per Ancestry, I am 14% European Jewish. My cousin matches are full of Jewish people, including a few who helped us ID who our "surprise" Jewish Ancestor was. We didn't know about this man until we took the DNA test..........his place on the family tree was occupied by a Welsh miner, who was the namesake of the family and probably father of my great-grandmothers siblings.

The J-test comes back at 6.29% for me, which seems to be below the cut off for Oracle to include the AJ category in their population approximations of my heritage.

However, my dad comes in at 8.59%, which leads to these Oracle approximations...

Using 4 populations approximation:
+++++++++++++++++++++++++++++++++++++++++++++++++
1 AJ + English + English + IE @ 5.941276
2 AJ + English + English + English @ 5.955135
3 AJ + English + English + Orcadian @ 6.012372
4 AJ + English + English + Scottish @ 6.151381
5 AJ + Cornish + English + English @ 6.233891
6 AJ + English + IE + NL @ 6.250544
7 AJ + English + IE + Orcadian @ 6.264150
8 AJ + English + English + NL @ 6.266247
9 AJ + English + IE + IE @ 6.270435
10 AJ + English + Orcadian + Orcadian @ 6.288060
11 AJ + English + English + NO @ 6.324598
12 AJ + English + NL + Orcadian @ 6.329527
13 AJ + English + IE + NO @ 6.375679
14 AJ + Cornish + English + IE @ 6.380507
15 AJ + English + English + South_&_Central_Swedish @ 6.382859
16 AJ + DK + English + English @ 6.396538
17 AJ + DK + English + IE @ 6.406605
18 AJ + English + IE + South_&_Central_Swedish @ 6.408375
19 AJ + Cornish + English + Orcadian @ 6.411687
20 AJ + English + NL + Scottish @ 6.411944

So long story short:

1. Use both Ancestry and GEDmatch to see if you can find any Jewish cousin matches.
2. If you have any other relatives to test, especially prior generations, you may be able to find a individual who still carries enough gene markers for a more conclusive result.
Reply With Quote Quick reply to this message
 
Old 03-14-2018, 08:01 AM
AFP
 
6,063 posts, read 3,622,558 times
Reputation: 5235
@ Westsideboy could you please post your oracle results for comparison.
Attached Thumbnails
Ancestry VS Gedmatch-j-test-oracle.png  
Reply With Quote Quick reply to this message
 
Old 03-14-2018, 10:09 AM
 
Location: Cumberland
4,558 posts, read 7,617,865 times
Reputation: 2769
Quote:
Originally Posted by AFP View Post
@ Westsideboy could you please post your oracle results for comparison.
Jtest Oracle population reference data revised 06 Nov 2012.

Admix Results (sorted):

# Population Percent
1 NORTH-CENTRAL_EURO 24.48
2 ATLANTIC 23.85
3 WEST_MED 11.77
4 SOUTH_BALTIC 11.60
5 EAST_MED 7.80
6 EAST_EURO 7.80
7 ASHKENAZI 6.29
8 WEST_ASIAN 4.36
9 MIDDLE_EASTERN 1.52


Finished reading population data. 78 populations found.
14 components mode.

--------------------------------

Least-squares method.

Using 1 population approximation:
1 West_&_Central_German @ 7.095385
2 FR @ 7.575065
3 NL @ 7.987523
4 English @ 8.688212
5 Cornish @ 8.778243
6 AT @ 10.080274
7 Orcadian @ 11.085456
8 IE @ 11.849434
9 DK @ 11.960705
10 Scottish @ 12.595473
11 NO @ 14.149290
12 PT @ 14.174778
13 South_&_Central_Swedish @ 14.588322
14 ES @ 15.368076
15 HU @ 16.476751
16 Serbian @ 17.093691
17 North_Italian @ 17.278740
18 North_Swedish @ 18.082876
19 RO @ 19.835680
20 Tuscan @ 21.782566

Using 2 populations approximation:
1 50% FR +50% West_&_Central_German @ 4.454061


Using 3 populations approximation:
1 50% English +25% Scottish +25% South_Italian_&_Sicilian @ 2.913021


Using 4 populations approximation:
+++++++++++++++++++++++++++++++++++++++
1 English + Scottish + Tuscan + West_&_Central_German @ 2.838630
2 Cornish + English + Tuscan + West_&_Central_German @ 2.881214
3 Scottish + Tuscan + West_&_Central_German + West_&_Central_German @ 2.884478
4 AT + English + Scottish + Tuscan @ 2.886180
5 English + Orcadian + Tuscan + West_&_Central_German @ 2.886604
6 English + English + Scottish + South_Italian_&_Sicilian @ 2.913021
7 NL + Scottish + Tuscan + West_&_Central_German @ 2.916995
8 English + English + Tuscan + West_&_Central_German @ 2.973484
9 NL + NL + Scottish + Tuscan @ 3.029376
10 Cornish + English + NL + Tuscan @ 3.040437
11 NL + Orcadian + Tuscan + West_&_Central_German @ 3.050304
12 English + English + Orcadian + South_Italian_&_Sicilian @ 3.056002
13 Cornish + NL + Tuscan + West_&_Central_German @ 3.056457
14 English + NL + Scottish + Tuscan @ 3.057130
15 Cornish + Orcadian + Tuscan + West_&_Central_German @ 3.069897
16 English + NL + Orcadian + Tuscan @ 3.073421
17 Orcadian + Tuscan + West_&_Central_German + West_&_Central_German @ 3.082393
18 DK + English + Scottish + South_Italian_&_Sicilian @ 3.086658
19 Cornish + DK + Tuscan + West_&_Central_German @ 3.087253
20 Cornish + Tuscan + West_&_Central_German + West_&_Central_German @ 3.102884


As mentioned, it seems I fall below the cut off for Oracle to include AJ in my population approximations on the J-test.
Reply With Quote Quick reply to this message
Please register to post and access all features of our very popular forum. It is free and quick. Over $68,000 in prizes has already been given out to active posters on our forum. Additional giveaways are planned.

Detailed information about all U.S. cities, counties, and zip codes on our site: City-data.com.


Reply
Please update this thread with any new information or opinions. This open thread is still read by thousands of people, so we encourage all additional points of view.

Quick Reply
Message:


Over $104,000 in prizes was already given out to active posters on our forum and additional giveaways are planned!

Go Back   City-Data Forum > General Forums > Genealogy
Follow City-Data.com founder on our Forum or

All times are GMT -6.

2005-2018, Advameg, Inc.

City-Data.com - Archive 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35 - Top