What to do with your DNA test

Some of my cousins and friends have tested at 23andme or familytreeDNA, due to my urging, and now they are asking me what to do next. I dedicate this post to them.

Autosomal DNA testing will not not magically find your ancestors. You will need to work at it and may have very little success if not enough of your known and unknown relatives have tested. It will give you many clues and hints about where your ancestors were from. Be sure to use some of the admix tools at GEDmatch.com on your results if that interests you, see my post on GEDmatch.

I suggest that if you are not familiar with DNA or DNA testing that you read my DNA basics page and if you have tested at 23andme also read my post on 23andme basics.

Assuming that you all do not want to spend the kind of time on this that I do (an hour or two most days for the last year); here is how to get the most for the least time input.

First you need to understand that an autosomal DNA test is nowhere near as definitive as a Y chromosome test, it can show you that you are related because you share runs of identical SNPs (referred to as segment matches from here on) with someone but not exactly how or even how close. After the 2nd cousin level the amount you will share with a relative gets more and more random. I have a few 9th cousins I share a one segment match with who like me have extensive trees and that is the closest match we have found. ISOGG has published the expected ranges of cMs and number of segments on their wiki that relatives share at different levels of relationship.

So what was your objective taking the DNA test? If it was just to satisfy your curiosity then my post on 23andme basics should answer your questions. If finding new relatives is of interest then read on.

If you are adopted or looking for your biological parent go to http://www.dnaadoption.com and learn more about using DNA for adoptees. In addition, there is a DNA group specific to adoptees at http://groups.yahoo.com/neo/groups/dnaadoption/info . Finally, there is a group of Search Angels willing to help you out with your basic Adoption search. Find out more at http://groups.yahoo.com/neo/groups/SoaringAngels/info

If you are looking to break a genealogical brick wall then you need to test other relatives as well as other possible relatives in order to prove or disprove your theory. You will also need to learn more about using DNA in order to do this. I recommend Kelly Wheaton’s lessons on Genetic Genealogy for that –
https://sites.google.com/site/wheatonsurname/beginners-guide-to-genetic-genealogy . I used Y DNA testing to prove that my ancestor Lars Monsen was descended from Mons Aasveidt and wrote two posts about that. Another brick wall was solved by a DNA cousin who looked to be close but is only about a 6th cousin to Dad however he has several common ancestors with us. This is one of the problems with endogemous populations and small geographic areas of ancestry, multiple common ancestors make a relationship look closer than it is.

So now to the intent of this post, if you are just curious what should you do about that long list of “DNA relatives” at 23andme or those on your family finder matches at familytree DNA. Or if you uploaded your data to GEDmatch.com then how many of your “relatives” there should you contact?

Contact everyone who is listed as a 2nd-4th or 3rd to 5th cousin or closer.  At GEDmatch that is 4 generations or less. Send them a message with your surnames and localities back to your gg-grandparents if you can and/or a link to your online family tree if you have one. I recommend uploading a GEDcom of your family back 4 or 5 generations to WIKItree.com which is free, has good privacy rules, and has slots to enter your haplogroups and DNA tests taken. Then you can send the URL of your tree to possible relatives.

When contacting a public match at 23andme send them a message first then go to their profile page to issue a share if you are interested in the overlapping DNA.

  • Don’t send shares if you are not interested in the DNA just contact them with names and localities
  • Ignore anyone with a one segment matches less than 15cM or so. Or even ignore anyone with one segment matches of less the 0.20% at 23andme. But if they want to share with you, that’s fine, accept and let them do the work.
  • The DNA becomes interesting when you share the same segment with several relatives. See my post on finding relatives with autosomal DNA for more about doing that.

Some people feel like the testing companies have oversold their services. Maybe there is some truth to that but the real truth is you will get out of this what you put into it. So if you don’t have lots of time for it, then don’t be frustrated by the lack of results. Maybe you will get lucky and find a DNA relative like me who will do most of the work for you!

Here is my four generation tree embedded here from wikitree:


3 thoughts on “What to do with your DNA test

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  1. I recommend you develop a standard email/message. Include your name, email, link (URL) to your Tree and a 1-2 sentence overview of your Ancestry. Send this to every Match – you can start with the closest matches, but plan on including everyone, someday. You never know who might have key info for you. Your Tree should be as robust (full) as you can make it – include iffy ancestors. This Tree is your net to catch cousins (to find Common Ancestors) – you want it as big as you can make it – 12 generations, if possible. Think of your list of Matches like a salesman treats such a list – they are all potential sales, and making contact and sharing info is up to the salesman (and to you). Jim jim4bartletts@verizon.net

  2. The companies have oversold their services. FGC claiming a full Y when its Y is more of 1/4 Y. The only major company that may not oversold its services is FTDNA. AncestryDNA and 23andme are both overselling a lot more than they can deliver. The new 23andme chip is a huge downgrade and they are trying to pawn it off as an improvement.

    People need to contact all of their 23andme matches to avoid them disappearing without explanation.

  3. On the DNA-NEWBIIES list at yahoo groups a contact made the following wonderful observation

    genealogists are used to focusing their research in one area at a time and they want tools they can bring to bear on their priorities, not tools that they must randomly react to. At first, atDNA felt to me a bit like a Roomba vacuum that is running all over the house, revacuuming areas it’s already been over and occasionally covering new areas. I want to use it like a manual vacuum, directing it to the areas that I want it to go.

    and another set of thoughts from this family tree DNA user …

    “So, if I want to direct my research to certain families, what do I do?

    This might be obvious to you, but it wasn’t to me. So far, I’ve come up with a couple of ideas:

    1. Test cousins in the family line you want to research and then triangulate on them to narrow down your match pool to just that line. Since we were researching a fellow who was born in 1759 with several sons, I thought it would be a good idea to test 5th cousins who descended from each of those sons. Uh… no. I didn’t realize that there was only a 1 in 10 chance they would match each other or me. Now I realize it might have made more sense to test 2nd cousins. I can’t focus as tightly, but at least they are likely to match me!

    2. Download your match file from FTDNA and load it into Excel and search the entire file for surnames associated with the line you want, then focus in on just those matches (and the matches you are led to by triangulating on them).

    3. Don’t forget that FTDNA is adding new test results all the time (every month? every two weeks?) so you have to look at recently added matches for the surnames you want to research.”

    Personally (Kitty speaking here), My opinion is that you should get as many 2nd and 3rd cousins to test as you can if genealogy is your interest.

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