Unsure of how other people were sorting their Shared Matches from AncestryDNA, I developed my own method: the Leeds Method of DNA Color Clustering. This simple and quick method helps you easily visualize how your close cousins are related to you and each other.
I created this method while working with an adoptee, and it works wonderfully for unknown parentage cases where the cousins are strangers and their true relationships are unknown. It also works wonderfully with traditional genealogy. In fact, it is being used to break down some more recent brick walls!
DNA Color Clustering: The Method
Step 1: List 2nd and 3rd cousins.
For this method, I use AncestryDNA and skip any “close family” and “first cousin” matches. Instead, I use cousins Ancestry says are “second” or “third” cousins. However, I do eliminate any of the matches near the top who share over 400 cM. (In other words, use those matches who share between 90 and 400 cM of DNA with you.) The key is to not include anyone who you share two grandparents with. For the spreadsheet, I am using Excel. I add “borders” around each cell – this helps everything stay readable when printed – and I “fill” the cells with color to create the color clusters.
Step 2: Assign a color to your first DNA match.
In this example, I assigned blue to person 01.
Step 3: Open that person’s shared matches and assign each of them the same color in the same column.
In this example, 01 showed shared matches with 02, 06, & 08. Each of these people are now a part of the Blue Cluster.
Step 4: Locate the first person who does not have a color assigned and assign them a color in the next column.
In this example, person 03 is the first person who is not already a part of the Blue Cluster. So, they were assigned the color orange in the next column.
Step 5: Open that person’s shared matches and assign each of them the same color in the same column.
In this example, 03 showed shared matches with 09 and 11. Each of these people are now a part of the Orange Cluster.
Note: Even though it didn’t happen in this example, a person would be assigned as part of the Orange Cluster even if they were already a part of the Blue Cluster! When someone is part of more than one color cluster, I call it cluster overlap.
Step 6: Repeat steps 2 through 5 until all of your 2nd & 3rd cousins have at LEAST one color assigned to them.
Analyzing the Results
4 Columns, No Overlap:
If your results show 4 distinct color clusters, like below, without any overlap, your sort is likely showing matches to your four sets of great grandparents.
Fewer than 4 Columns, No Overlap:
If your results show less than 4 clusters, it is likely these clusters represent 3 of your 4 sets of great grandparents and that you have no matches at the 2nd/3rd cousins levels who have tested for the 4th set of great grandparents.
Some Overlap:
If your results show 4 clusters but some of your matches have been assigned more than one color (for example, 02 and 04 are both blue and orange), your sort is likely showing either your four sets of great grandparents, but also showing you that two of these results (i.e. blue & orange) are on one side of your family. Or, the overlapped clusters (blue & orange) might belong to one set of great grandparents and, in this example, you are missing matches for one set of your four sets of great grandparents.
Lots of Columns & Overlap:
In this example, there is a lot of overlap between all of the clusters except the yellow and brick red clusters. All of the overlapping clusters are on the maternal side of this test taker and visually show a lot of cousins marrying cousins resulting in pedigree collapse. The paternal mother’s side is represented by both the yellow and brick red clusters. The paternal father’s side has no cousins matching at the 2nd/3rd cousin levels. So, even though there are a lot of clusters and matches, this sort represents only 3 of the four sets of great grandparents for this individual.
NOTES:
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- Your results may vary!
- Color Clustering, as with most DNA results, is not proof of a specific relationship. Instead, it is a clue that can be helpful in determining relationships.
- Although all the results shown in this post are real, the names have been hidden for privacy reasons.
- A special thank you to everyone who allowed me to access their DNA results and gave me feedback! And, a special thank you to John Motzi who provided a lot of feedback!
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