When you open the match details page, if there is a family tree available but not attached to the DNA test, it will have a drop down menu where you can select the tree to preview (shown above and left). In the screenshot above, it shows how initially, it looks like this DNA match has no family tree, but they do have one unattached to their DNA results. Selecting it from the drop down menu brings up a preview. It's a small tree, but enough to identify our most recent common ancestor, since their grandfather was the brother of my great grandmother.
This one you do need to be careful with because while sometimes, people simply forget to attach their tree to their DNA test, it's also possible that the family tree doesn't belong to the person whose test you match (or the tree may belong to that person but they are not the "home person" for the tree, as is automatically selected). For example, one of my close cousins has taken the test, but his wife is managing it. His wife has started her family tree, but not his, and I only know this because I know them well enough to know whose tree it is. To anyone else who doesn't know them, they could mistake the wife's tree for his own. In this case, there is a good reason the tree wasn't attached to the test. So definitely look for those unattached family trees, but don't make too many assumptions about them.
|Don't dismiss a tree like this!|
Don't dismiss trees that seem too small to make any use of. As long as they have deceased ancestors in their tree (whose details are therefore public) you can do what genealogists do best: research! Build on that tiny shrub of a tree, researching further back than the tree owner did until you find your common ancestor.
In the example above/left, you might look at this family tree and think there is not enough information to find the most recent common ancestor, but you'd be wrong. This person's father is a descendant of my 4th great grandparents John Hendricks Godshalk and Barbara Kratz. How do I know? Because I took this tiny tree and I researched the ancestors until I connected it to my own tree.
3. Build downwards on your own tree.
Research all the descendants of your known ancestors, as far down as you can. It really helps when you're trying to make a connection with a small 'shrub' of a tree such as discussed above. You won't have to research your match's tree back very far if you've already done the work on your own tree.
This is especially useful for trees with endogamy - for example, I have a branch of Mennonites on my tree and after tracing many other descendant lines of my ancestors, it quickly became clear there are a number of surnames that are strongly associated with the colonial Mennonites who settled in Pennsylvania, especially when more than one appears in a tree. So if I see names in someone's tree like Oberholtzer, Funk, Detweiler, Bergey, etc, even though none of these are my ancestors, I immediately know they are likely from my Mennonite branch just from seeing the surnames. In fact, in the screenshot above the match's father's name was Detwiler, immediately suggesting I should follow that side back until it linked to my own tree, and it did. Even on branches without endogamy, it can still be useful, just not as immediately apparent.
|Notes always showing in list allows me to quickly see|
which ancestors I share with matches I have in common
If there really is no tree whatsoever you can make use of, and the person won't respond to your messages, all you can do is look at the DNA matches you have in common with each other. If any of them are matches you've already determined your shared ancestry with, then it's possible this match is also descended from the same branch. If more than one are descended from the same branch, then it's very likely this person is too. The more shared matches who descend from the same branch or ancestor, the more likely the person with no tree does too.
This process can be sped up greatly by using a Chrome extension called MedBetterDNA. It has the option to "always show notes", which means any notes you make on a DNA match will show up in the list of matches, including the list of Shared Matches. In other words, every time you identify the shared ancestor of a DNA match, make a note of that ancestor in the notes section, then every time that match is a Shared Match with someone else who doesn't have a tree, you will know it without having to open up additional match's details. See the screenshot example above. I can't not stress enough how much more efficient this has made my workflow.
5. Use the Search option for private trees.
It's frustrating to see all those private trees, especially when the owner doesn't respond. But you can get an idea of what surnames are in their tree by using the search option. That doesn't mean your shared ancestor is definitely from that surname, but it is especially useful for private trees you have a Shared Ancestor Hint with. Knowing you do have a shared ancestor with that match makes it much more likely a shared surname is the source of that ancestor. This method is a little tedious though, since you have to randomly search for surnames from your tree and hope you get a hit for the match you're looking for, but you should theoretically get there eventually if there is a Shared Ancestor Hint. However, be aware that the search function isn't hugely reliable and often misses people who definitely have a surname you're searching for in their tree. I think it's a site indexing issue. So it doesn't always work, but when it does, it's helpful. It is also useful in combination with the above tip (a surname search result plus Shared Matches who are confirmed from the same branch as that surname is very good evidence your Shared Ancestor Hint is from that branch).
Testing family members, especially parents, is beneficial because you can at least see which of your matches also match those family members, and therefore which side or branch of your tree the shared ancestor is likely from. No tree? Won't respond to messages? No shared cousins who have been identified yet? Well, at least I can see whether they match my mom, dad, paternal grandfather, or any of my known, close cousins on either side who have tested.
Be aware that the Shared Matches feature only includes high confidence (or higher) matches who are estimated 4th cousins or closer, but if you manage any of your family member's kits, you can see which matches you have in common at any level/degree by opening that match's profile. In the example above, you'll see my dad (Jim) matches Agnes and two other kits she manages, even though they do not meet the criteria of "Shared Matches". So when I look at Agnes or her other kits in my match list, it won't show my dad as a shared match to them, even though you can see here by opening Agnes' profile, they are a match to my dad. So not only testing other family members, but getting permission to manage their test is also very beneficial to at least figuring out which side/branch someone is connected to.
7. Search the internet for your DNA match
This one may seem a little intrusive to some, but the data is public and it's out there, so why not make use of it? There are certain websites like familytreenow.com, truepeoplesearch.com, and pipl.com where you can search for people by their real names, or sometimes by a username. Even just a Google search can yield results. Some people use their real names on AncestryDNA - so search for it. Sometimes, you can find them on Facebook or other contact details. Sometimes, you can find out their parents names, and from there, build a tree and connect it to your own. I know these sites can be controversial to some who feel they are a violation of privacy, but they are using public data and not violating any laws. If you are concerned, you can request your information be removed from these sites.
Even when people use anonymous usernames, sometimes they post on Ancestry's message boards and you can find them by Google's the username. Sometimes they use the same username on other websites and you can get in touch with them that way.