What to expect from your genealogical DNA results

What to expect from your genealogical DNA results

You’ve sat patiently (barely) while Ancestry.com has processed your DNA test, and like Christmas morning it’s FINALLY time to open the mysterious gift of your DNA results…and about 10 minutes later you’re going to be asking yourself “what do I do with this?” Let’s go over my experiences with this process, and hopefully set your expectations properly, so you’re not discouraged from what is a much more complicated process than you’d ever expected. I’ll also be posting subsequent “How-to” guides on how to show how I made the most of my DNA results, but for today, let’s look at what to expect.

Before we start, however, there are two things I want to make clear: 1. I’m still very supportive of this process, and have no hesitation recommending it to others! It can be tough, confusing, frustrating and still totally worth it and  rewarding (just like traditional genealogy btw!); 2. This is written in 2017 and we are just scratching the surface. This is likely to get better as the years go on, and more tests are tested, and more money is made on the process, so more is invested to make it even easier.

With the disclaimers out of the way, here’s what I’ve learned to expect:

The DNA test will only show you other people you’re most likely related to, but it does not show you HOW you’re related.

There’s a misconception that after you receive your DNA results, that Ancestry will map the connection between you and your match for you. The truth is you will receive a list of people who share a common ancestor, however the connection is up to you and them to determine. For example, these two people match my mother-in-law, and I can see no more than that there’s a match:


Without trees to compare, there’s no way to establish the link. Also, conversely, one you establish a link between your trees, there is no way in Ancestry.com to prove that link. You will only be able to show the most likely path between you and your match.

You will need a solid, well researched, and as far reaching family tree to make the most of the results.

Everyone listed as a DNA match shares a common ancestor(s) with you, and the goal is to identify that relative. So obviously, the further back and more accurate your tree is, the more likely to have the ancestor that matches someone else’s! What I found was that as well as I thought I had my tree traced, as soon as I tried to match my ancestors I found how many holes I had!

Here’s an example (which I will follow through this post), from my wife’s tree:

tree-example-1This is her mother’s ancestors, and we faced some challenges building this line. There was little family history to rely on, and two realities of African-American genealogy played heavily into our work: especially in the South, it was often the culturally unacceptable to ask questions about family history, and, it’s amazingly challenging to firmly establish relatives born before 1870.

So this tree is quite an accomplishment, but since most of our matches are going to be 3x or 4x Great Grandparents, this tree demonstrates just how limiting an incomplete tree can be. In this case, of her 3x Great Grandparents I can identify 3 possible last names out of 32…so I only know 9% of the names in that generation.

Your tree will likely be way better than 90% of the trees attached to your matches, and thus you will spend most of your time building THEIR trees to find you common ancestors.

This is largest challenge I’ve found in DNA research: most people don’t even associate their results with a tree, or if they do it’s a very incomplete tree. Following the above example, here is a typical tree that is a DNA match:


Luckily, the match I’m working with does have a good tree to work with:


But, as you can see, the tree is not complete, and from it we’ll only be able to guess at 1 of 32 last names of the match’s 3x Great Grandparents. That’s only 3% of the last names of that generation, and combined we are starting with a less than 1% of matching 3x Grand Parents.

The best solution is to start building out your match’s tree, to see if you can find ancestors they haven’t identified in the hopes you will find your common ancestor. I currently have 9 trees of matches that I’m working on, and I’ve identified most recent common ancestors (MCRA) for 2 more using this technique. The downside is that building out trees to identify 64 3x Great Grandparents can be very time consuming.

The best researched lines of your tree will result in the majority of your matches, while the brick walls will likely remain.

This is a corollary to my last point, but I still want to bring it up. I went into DNA testing hoping it would breakdown some of the brick walls in my research, but it’s usually true that they are brick walls because there’s not enough data for anyone to make the connections in the first place!

My mother’s mother’s side of the family is well documented with many lines going back into the 1600’s (including our Mayflower line), and so it’s not surprising that 17 out of 27 DNA lines I’ve identified are on my Mother’s side of the family. Additionally, I have half a dozen 8th cousins identified on her side, but only 1 on my Father’s side…and that’s due to the work of a long-time Genealogy Society which has worked to establish a line he’s in back to the 1630’s (http://www.morsesociety.org/). Most of your DNA “wins” are going to be in areas you’ve already “won”.

Private trees will be the bane of your existence!

I won’t get into the debate of why someone should/shouldn’t keep their trees public, however you are going to find that some of your best matches will have private trees, but I’d estimate that 50% of our matches are Private trees, which effectively shuts down research on those lines. On my wife’s side the result has been that we can’t identify her closest DNA match on Ancestry.com, which has a 50/50 chance of solving a large hole in her family history. We have reached out to the match using Ancestry.com’s messaging tool, but…

Many people who took a DNA test will likely not respond to your emails.

I have sent over 20 messages to people who are our DNA match, and I have yet to receive a reply. For 2 of them, I sent them messages explaining how I’d done the research necessary to expand/correct their line, and link us together, and still no reply. I’ve had some better results with GEDmatch (which has you use your real email address), but even then the results are less than 50% response. There are few things more maddening than having a close match, who might be a good lead to a new discovery, and they have either no tree or a private tree, and they don’t reply to messages, but it’s going to be a common challenge you face.

These DNA test results are very powerful in ways that traditional genealogy isn’t, and it’s likely that some of the results are going to be deeply troubling.

DNA is going to enable you to prove relationships in a way that traditional genealogy can’t really accomplish, and it’s only a matter of time before you discover that you’re exposing a family secret. I’ll be posting about this separately, but know that you’re likely going to discover/prove information that not everyone is going to be comfortable with you discovering/proving.

More info on the risks of DNA testing: http://anamericangenealogy.com/2017/01/23/dangers-of-dna-testing

The amount of work to make use of your DNA tests means you’re going to spend less time on traditional genealogy.

After my first week of receiving my first DNA results I realized that I could spend the rest of my time doing genealogy research on nothing but my DNA results. It’s been a struggle to balance the time I have to research between traditional research and DNA research, but knowing that both are necessary to make the other useful has helped me consciously maintain balance between my work. Enjoy getting sucked into the black hole of new data, but after awhile, remember to come back to the work you’ve been doing!

When you finally do find that match through a brick wall, there’s nothing like it…and it’s likely you wouldn’t have gotten through it without DNA testing.

I will be writing about this more shortly, but I was recently reached out to by a DNA match who identified my wife’s 2x Great Grandfather’s name from our tree. My wife’s Grandmother is still with us, and she knew nothing about her Grandparents, but we’d found the name on her Mother’s death certificate. That was all we knew was that name, and despite the usual research nothing more had surfaced. This person who reached out to us has researched this line for 30 years, and has the most amazing documentation, but he’d never heard of the existence of my wife’s 2x Great Grandmother. Further research has linked us conclusively, and allowed us to sit down with my wife’s Grandmother and explain the very detailed history of a Grandfather she never knew. We would have NEVER found each other without DNA (and Public trees, and answering my emails!) and I can tell you that this one discovery makes all of the frustrations worth it!

Happy hunting!


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