What You Will Need
- Your DNA Matches in Triangulated Groups (Spreadsheet or Genome Mate Pro)
- Chrome Browser
- AncestryDNA Helper for Chrome (AncestryDNA Helper How-To PDF file)
- A Triangulation group spaning a large segment with a yet to be discovered connection
- Two or more AncestryDNA testers from that Triangulation Group(TG)
- Share links from any AncestryDNA testers who match on that segment.
Gather as many of the Share Links from persons in the TG as you can. Compare each of the members to each other(see image a) noting patterns of Surnames and Locations. This is similar to using the Share Tab Tool however you aren't limited to 4th or closer cousins(see image b). If you have a full sibling or full siblings which have also tested at Ancestry, obtain a share link from them if you do not already have one. Run a comparison of their test against the members of the TG and repeat the same process with their Trees looking at patterns in Surnames or Locations.
It's easier than ever to utilize the Share DNA Matches View now that both the Owner AND/OR the Guest Viewer have the ability to turn off the SHARE view.
Your results may vary but this method has worked for me each of the 3 times I have used it. The segment sizes in the group ranged from 19-48 cMs. You can do something similar to this using Match-O-Matic in DNAGEDCOM although you may have to use an older version of DNAGEDCOM to do that. I don't think it was in the last release. I run both versions on my computer. Hope this will be useful to others who are trying to map their chromosomes to the contributing ancestor or ancestor couple.