Ancestry has unveiled a new DNA tool and I have thoughts. DNA circles has been replaced with something called Thrulines. Thrulines attempts, based on all the trees in its database, to figure out where your DNA matches fit into your family tree.

In order to use Thrulines, a few elements must be in place. Obviously, since it’s DNA related, you have to have taken a DNA test. You also have to connect the DNA to a family tree which is searchable (searchable trees can be public or private). The tree must be built back at least four generations. This means that Thrulines won’t automatically be useful for adoptees and others who aren’t sure of their DNA heritage -but it’s still a boon to those working to figure that out. It also still disadvantages those who don’t have a lot of DNA matches, whose DNA matches don’t have trees, and, because it’s using all the trees in its database, not just trees with DNA matches attached to them, people who come from populations that don’t have a lot of family trees from those particular populations.

However, when it works, it’s pretty cool. Here’s an example of a Thruline I have that I was impressed by:

I am related to these three people through my maternal grandmother. I don’t have them in my tree, only their grandparents: the siblings of my grandmother. Still, Thrulines managed to correctly place these people in my family tree. To do this it not only had to piece our four trees together -it also used information about how much DNA we share (which can be anywhere between 45-515 cM for second cousins, according to my favourite chart). It’s interesting to note that in my list of DNA matches, the cousin with the lowest amount of shared DNA is in the third cousin category, while here they are listed correctly as a second cousin.

Thrulines can also give you potential ancestors based on shared DNA matches who have people in their tree that you do not. And here’s where it gets problematic in the same way the DNA circles were problematic. Ever heard the expression “garbage in, garbage out?” On the one hand, I don’t want to be a source snob. There’s a lot of good information out there and crowdsourcing sometimes does a good job of verifying it. On the other hand, I want to shake everyone who has identified the wrong Hannah as our ancestor and show them the records that I have with Hannah’s correct maiden name. This only bothered me a little bit before Thrulines, but now all I see for potential ancestors is the incorrect Hannah and her ancestors.

Here are a few other things to remember: absence of evidence is not evidence. Just because you have no DNA matches in your Thruline doesn’t mean that there aren’t any or that the line is incorrect (check out my post “Is This Normal?” if you have concerns). My aunt hasn’t connected her DNA to a tree, so my dad doesn’t have any DNA matches in his father’s Thruline. It’s also possible that no cousins have tested along a particular line, or that there are very few cousins who could have tested. It’s also possible that there are cousins out there with whom you share no DNA. Even evidence may not be evidence sometimes. My mother has two distant matches in a Thruline to her 5th great grand father. While it looks good on paper, the DNA might actually be from another unknown common ancestor. I can’t consider it “proved” by this that that man was actually our ancestor. See also: garbage in, garbage out. If a person has placed themselves incorrectly in their tree or their tree has errors, the conclusion that Thrulines draws from it will also be incorrect.

Overall, I can see the potential in Thrulines but it’s not quite there yet. While it’s a little more advanced than DNA circles, it still has some of its flaws. However, it has proved useful even though it’s still a little clunky to use. I hope Ancestry continues to improve both the user interface and the connections. It would be nice if we were able to reject some of the potential ancestors and never see them or their lines again. I hope it also encourages people to connect their DNA to a tree, no matter how small (and not just make a tree but connect their DNA to it!). Most importantly, remember that there are no magic wands.

Updated to add: you can provide feedback. No telling what will be done with it, but hopefully it will help!