Interpreting your DNA matches


Some of your comments have indicated a need for guidance in interpreting your DNA matches.  In our next release, we’ll be including some educational material that will assist with this activity.  In the meantime, here are three good starting questions to help you decipher if a potential match is a good candidate.  In evaluating a potential Y match, ask these questions: 

  1. On how many markers were each of the participants tested?
  2. How many markers do the participants share in common, or on how many markers do the participants differ?
  3. Is there a common surname? 

It is important when reviewing your match list that you and the other participant (match candidate) were tested on the majority of markers, Y46.  The number of markers acts similarly to a phone number.  An area code e.g. 12 markers, yields a large pool of individuals sharing that same 3 digit code.  A prefix (33 markers) refines you to an even tighter group of people and so on.  If you do have a match with a person tested at only 12 markers, for example, you may want to contact the individual, discuss the situation and encourage an upgrade to see if there is still a significant match with that participant with a higher resolution test.  

Next, you want to make sure that you match on all but two or three markers.  A most recent common ancestor (MRCA) number will tell you how related you are to your match.  It is a statistical analysis that takes into account the number of markers and the mutation rates, but it is meant to be used only as a guide.  Its purpose is to help you think about how many generations may separate you from a direct link to your potential match. 

Lastly, evaluate the surnames.  If you were tested on the majority of markers and do not differ by more than a few marker values, yet the surname is different, there could have been an adoption, illegitimacy or name change.  So, go ahead and contact the potential match and collaborate on determining where a common ancestor is shared. 

Y DNA and mtDNA differ not only in their inheritance patterns, their usefulness in genealogy vs. anthropology, the associated laboratory processes, but also within deciphering among potential matches.  For instance, mtDNA is a great ancient ancestry tool, but its near-ancestry (recent genealogy) value is not as great as is the Y DNA.  mtDNA is, however, helpful in targeted instances where you have a specific hypothesis you are testing.  If the results of the participants do NOT match, then you can conclude that the individuals do NOT share a common maternal ancestor; if, however, they do match you can NOT conclude that the do share a common maternal ancestor since many people will share the same mtDNA results.  Therefore, the correct “interpretation” is that you share common ancient maternal ancestry.

Some people connect instantly; others as the database grows.  Ancestry.com DNA will notify you of a potential Y match if that person is within 7 generations.  It is with the marriage of DNA and traditional paper genealogy that will show where and whom the actual common paternal ancestor is.  Should you ever have any questions about your matches or results, please contact our client services team at dna@ancestry.com. 

 

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May 8th, 2009
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Comment Number:
1
Written by:
marjorie wintle
Posted on:
May 9, 2009 at 4:57 pm

My great great grandmother was a Lincoln. Just before I was born (6/26/48), my mother, her sister and my first cousin were put on a geneology showing how ae are related to Abraham Lincoln, but I never have been able to find it. Is there any way that I can prove that he is an ancestor of mine? Thank you

Comment Number:
2
Written by:
Scott Kendall
Posted on:
May 9, 2009 at 10:39 pm

When is Ancestry going to offer more testing options? For nearly a year, Ancestry representatives have told me there are going to be tests with more markers. Are there plans to offer additional tests in the near future?

Comment Number:
3
Written by:
Topics about Ancestrys » Archive » Ancestry.com Blog - » Interpreting your DNA matches
Posted on:
May 11, 2009 at 3:07 am

[...] Wendy Jessen added an interesting post on Ancestry.com Blog – » Interpreting your DNA matchesHere’s a small excerptFor instance, mtDNA is a great ancient ancestry tool, but its near-ancestry (recent genealogy) value is not as great as is the Y DNA. mtDNA is, however, helpful in targeted instances where you have a specific hypothesis you are testing. … [...]

Comment Number:
4
Written by:
William B Evans
Posted on:
May 11, 2009 at 6:16 am

Thank You Wendy,

I too would like to see more testing options in the near future. The ability to upgrade from the 33 marker test (the one I took) to a higher level test would be fabulous. I know a few people that would take advantage of that immediately, myself included. I also feel you need to lower the price of the MTDNA test. The usefulness of the MTDNA tends to be more ancient heritage as you explained so for the price paid, I feel most people are disappointed with what they pay and what they can actually do with the results.

My family suspects Native American heritage but I won’t spend 180 just to get a haplogroup association. Familytreedna offers a 99 dollar basic MTDNA test I will probably take. I would rather do this with Ancestry, but the cost is not competitive.

I do like what I have seen over the past 6 moths or so with the improved DNA reports and graphic representations etc..

One more question, Is Ancestry no longer associated with Sorenson? I see you no longer have a link to their site.

Thanks for your time!

Comment Number:
5
Written by:
Richard Warren
Posted on:
May 11, 2009 at 7:41 am

I would like to know if it is possible to upload dna profile data obtained from a different lab (genebase in my case).Having already spent several hundred $ on Y- and Mt- dna tests it would be nice to have access to the ancestry database without duplicating the tests.

Comment Number:
6
Written by:
William B Evans
Posted on:
May 11, 2009 at 8:02 am

Richard, yes you can join Ancestry for free and upload your results. Its very easy. Many people do this in my DNA group.

Comment Number:
7
Written by:
Carl Jennings Smith
Posted on:
May 13, 2009 at 8:03 am

I am disappointed with the information that I received from my test results. I expected more than the general information that could be applied to most anyone,rather like reading my horoscope in the newspaper. Any good world history book can provide the same migratory information.

Comment Number:
8
Written by:
Tom Gurney
Posted on:
May 14, 2009 at 5:59 am

This is a good detailed blog on a topic quite new to me. My Uncle recently discovered our family roots back to France which was a big surprise! We haven’t used DNA though and perhaps that can help to uncover more detailed findings about the past of my family.

Comment Number:
9
Written by:
Wendy Jessen, Ancestry.com
Posted on:
May 19, 2009 at 9:30 am

It is encouraging to see the desire for additional testing and efficiencies. Thank you for your comments and your support of the existing structure.

First, upgrades from the 33 marker Y test to the 46 marker Y test can be requested now by calling our client services team at 1-800-958-9124. We intend to provide this functionality in an automated fashion later in the year.

Second, a higher resolution Y DNA test is something that we would like to offer our customers at some point but is not likely to be released this year.

Furthermore, we are constantly working with the laboratory “mechanics” to implement additional economies of scale and scope. Our intention is that these cost savings will benefit our clients. Specifically with respect to the Native American designation, there may be a research laboratory which performs population genetics studies – this would be the most accurate source for specific information on Native American ancestry and heritage. Y and mitochondrial haplogroups are tied to Native American groups, but the entire Native American group is too homogenous to give differences between tribes.

Lastly, we are currently in talks with SMGF about getting the easy link to search their database back onto our site but at this time we do not have a good estimate on when that will be. We will for sure update our users when we have an estimate on timing.

We are constantly working to improve our genetic testing options so, I would check back often to see if we have updated our testing. Our research is ongoing and if enough individuals request given types of testing, we will do our best to meet the need.

Thanks for all your feedback. We so appreciate your comments as they are incredibly valuable to us as we work with our engineers on what features/products to release next.