The other day I posted about how some of my Ancestry DNA matches looked on in the Shared Clustering Tool. Today I’m comparing that same cousin — my 4th cousin 1 removed and my mom’s 4th cousin — against my Mom’s Ancestry DNA matches both in the Shared Clustering Tool and Node XL.
Cousin “Jane” (as I’ll call her) shares a set of 3rd great grandparents with my mom: Jacob Copple and Margaret (Blalock) Copple. She shares 71 cM in 4 segments with my mom, according to Ancestry. I can see 3 of those segments clustered in the Shared Clustering tool. One segment appears to tie to matches with a Blalock/Blaylock in their tree and/or a segment on chromosome 9 (based on those matches who are also on 23andMe, FTDNA, MyHeritage or GedMatch). A second segment matches another possible Blalock segment, likely on chromosome 13. Finally, a third segment cluster is with matches whose MRCA is likely Jacob Copple’s parents (Philip Copple & Patsy Wright) or grandparents.
The orange line vertical and horizontal (in both pictures) represents cousin “Jane”. The three blue arrows above show the three main clusters she shares with Mom and with other matches of Mom’s.
Below is a zoomed-in look at the “chromosome 13” segment cluster.
Below is the likely chromosome 9 cluster. The blue labeling in the rows and columns represent matches who have a Blalock/Blaylock in their own trees. (Of course, the shared DNA may be due to another family line altogether, but the evidence at this point seems to be hinting at Margaret Blalock’s line rather than her husband Jacob’s.)
Can I see three clusters for “Jane” using the Node XL tool? Actually, yes, I can. The Node XL tool is not as intuitive to use as the Shared Clustering tool, and I don’t know the algorithms behind either, but it’s reassuring when different clustering tools give somewhat similar answers!
Cousin “Jane” is highlighted in red. She is based in the green group, and matches the hunter-green group, the chartreuse group, and a whole bunch of my mother’s matches in the gold group. The Node XL clusters are limited to Mom’s matches of at least 15 cM.
I haven’t done enough research with the groups in the Node XL tool, but I was intrigued by “Jane’s” cluster. It looked like there were actually two groups — and sure enough, there are two groups, as you can see below. I’m not sure why the cluster was not split out in a definitive manner, as there is not a lot of crossover between them.
If you’ve used Node XL regularly, do you know why that might happen? Perhaps it’s the algorithm used?
Finally, in addition to more study of Node XL, I need to run a clustering report on the Genetic Affairs tool, which I haven’t used much. It would be interesting to see how “Jane” clusters with my mom’s closest matches using that tool.