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Small cM DNA Matches

Do you remember having conversations with your parents similar to ‘Why can’t I? Everyone else is doing it.’ Well, that is how I sometimes feel when it comes to my DNA research strategy. In other words, I often haven’t had a specific strategy, but was following the ‘crowd’.

That was at least true when I submitted my spit to Ancestry to have an autosomal DNA test completed over 4 years ago. At the time, I didin’t know much about DNA but was hoping that it would help break down the numerous brick walls in my family tree.

It was only after getting my results back that I started learning about the perceived limitations of these results.

Since my tree was already complete thru 5 and 6 generations and mostly complete thru 7 generations, my hopes of using my Ancestry DNA results to prove a new ancestor were dashed.

Then came the summer of 2020 when Ancestry announced that it had plans to remove the 6 and 7 cM matches from our lists of matches. Since Ancestry had also recently announced that over 18 million people had had their DNA tested by Ancestry, I knew that these smaller matches were adding to the data load. Thus, I looked at this move for what it was – a cost saving measure.

That was until I looked at my own ThruLines data and realized that I had ‘brick wall shattering’ information in my ThruLInes that utilized quite a few of these smaller matches to build these connections.

Thus, I started working to tag these smaller matches — starting with those identified as having a common ancestor. In working thru these matches, I found matches to support my paper research identifying Rachel Harris, daughter of Peter Harris as my third great grandmother. These matches helped me identify Peter’s wife along with the parents of Peter Harris and his wife, Rachel Simonse VanArsdale. This discovery led me to three revolutionary war ancestors and a very rich family history going back to the 1600s.

Knowing that there had to be other ‘yet to be identified’ common ancestors lurking in this pool of 6-7 cM matches, I decided I was going to try and tag as many of these matches as I could. Roberta Estes provided some guidance on how to do this in her blog on July 16: Ancestry to Remove DNA Matches Soon – Preservation Strategies with Detailed Instructions. So, I started by searching these matches for some of my surnames and then tagging them. Since this was a slow labor intensive process, I knew that I wasn’t going to be able to save very many of these matches.

Then I saw a post by Roger Froysaa on the Facebook group, Ancestry DNA Matching where Roger shared a script that could automatically tag these 6 and 7 cM matches. Roger not only shared several versions of his script but also wrote a script to cause the list of matches to scroll to the bottom. These scripts worked — to a point. I would either get an ‘Aw Shucks’ your browser crashed OR a message from Ancestry that their backend servers were overtaxed. Charles Updike shared changes to the script, including a different script to scroll to the bottom.

This morning, I saw another post on the AncestryDNA Matching group about these scripts. This post was by Kay Simpkins where she shared a script written by Earl Haiks. I found the script in one of Kay’s comments on her post and copied/pasted it into Notepad.

After reading all of the comments on Kay’s post, I realized that I didn’t have to sort out the 6-7 cm matches, I just had to run the script. I renamed my ‘6-7 cM Matches’ group and called it ‘Distant Relatives’ so that I wouldn’t have to edit the script shared by Kay. I then ran it on my matches — and it was QUICK and I didn’t get any of those error messages. In about 4 hours early this morning, I was able to run this script on five tests. I still have one test to run the script on but am waiting until tonight when it should run faster than midday.

Below are the stats for these five kits:


Now, I just have to continue researching ancestors / descendants on my tree so that Ancestry’s computing power can figure out the common ancestor for these distant matches.

None of this would have been possible if others had not been willing to share via a blog post or Facebook community. Thank you Roberta Estes, Roger Froysaa, Charles Updike, Kay Simpkins and Earl Haiks for your contributions to this conversation. Also a shout out to Jason Lee for creating and administering the AncestryDNA Matching Facebook group.