Are you ready to organize your DNA matches? Creating a Leeds cluster chart to divide your closer matches into four grandparent groups can get you started. Through trial and error, I’ve learned some tips that will help you be more successful.
What is a Leeds Chart
Dana Leeds developed this methodology in July 2018 while helping a person with unknown parentage discover their biological family. With this type of case, you don’t have the luxury of recognizing any close relatives, so Dana needed a way to separate the person’s match list into family groups. She started with an Excel spreadsheet and the DNA matches ranging from 90 cM to 400 cM with the idea that she’d be using 2nd and 3rd cousins and be able to separate out four grandparent groups. To learn more, see Dana’s website. She has many blog posts about the method.
Challenges
As we’re asking our older relatives to test – those closest generationally to the ancestor – we’re seeing a wide range of generations in the match list, such as the children and grandchildren of 1st cousins. If we include these DNA matches in our Leeds chart, it will skew the chart and it will be less helpful.
For example, I’ve asked my cousin, Lucretia to share her DNA results with me to use for my Shults and Royston lines. She is a generation closer than me and has better matches. Her grandparents, William Huston Shults and Dora Algie Royston, are my great-grandparents. We have many brick walls on those lines and I’m using DNA to confirm my hypothesized ancestors from documentary research.
My first attempt at a Leeds chart for Lucretia’s DNA matches did not result in the nice neat set of four columns representing each of her grandparent lines: Becker, Correl, Shults, and Royston. Instead, it resulted in many columns with a great deal of overlap. 
At first, I thought this represented multiple relationships or pedigree collapse since these were southern lines. Then I realized that I was using DNA matches who were the children and grandchildren of Lucretia’s first cousins, not second or third cousins. Because they are further removed generationally from Lucretia, they share small amounts of DNA and look like second or third cousins.
In the image below, all the green boxes represent close DNA matches to Lucretia – and most of them are first cousins, once, twice, or three times removed (1C1R, 1C2R. 1C3R). Notice that if we were using the 90 cM to 400 cM parameters for the Leeds chart, many of these matches would still be included. Since they all descend from William Huston Shults and Dora Algie Royston, they would match on both the Shults and Royston lines and create the overlap seen in the Leeds chart above.
Removing the children and grandchildren of first cousins resulted in a much cleaner chart. I used DNA matches of 90cM to 288 cM, and the chart separated clearly into the four grandparent groups I hoped for. I colored the maternal lines pink and purple and the paternal lines blue and green. Interestingly, the Correl line had only one DNA match included in the chart. Most of the matches in this line share less than 90 cM. Now I have a clear idea of how Lucretia’s DNA matches fit with the family. If they didn’t have a family tree attached, this would get them in the right bucket.
Tips for Creating a Leeds Chart
Tip # 1 Use Ancestry ThruLines to Discover 1st Cousins, their children, and their grandchildren
If you have a family tree on Ancestry and connect it to ThruLines, you can see where those closer matches fit in. Often, we recognize some surnames, but not always. Even if the DNA match has a private tree, as long as it is not designated unsearchable, the connection will show up on ThruLines. For instance, in the image below, I was unsure where some of the matches fit, but ThruLines showed me the likely placement on our tree. Of course, we want to verify the relationships, but this gives us a starting point.
Tip # 2 Add Notes to DNA Matches
Once you’ve discovered a connection to a DNA match, be sure to add it to a note on the DNA testing company website. This will help you as you’re selecting the matches for your Leeds chart. You’ll easily be able to eliminate the first cousins and their children and grandchildren. The below image illustrates the note on Lucretia’s DNA match page for me as her first cousin once removed.
Tip #3 Create your Own Diagram of Closest DNA Matches
Using a diagramming program like Lucidchart or Diagrams.net, chart out the closest matches for the test-taker. Some DNA matches may not appear on ThruLines if they don’t have a tree connected. Once you’ve discovered the connection, you can create a master chart of the closest matches for reference. See my example above of the chart I created for Lucretia’s close matches.
In closing, be sure to try the Leeds method on all the DNA testing websites. It will help you separate out the grandparent lines and get you started on making new discoveries via DNA.
Best of luck in all your genealogical endeavors!
Watch my video explaining this methodology.
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Thanks for the note!