I’m just playing with the new tool on DNA Painter – ‘Cluster Auto Painter’. I have created MyHeritage clusters for the DNA test results of my Mum & her brother – for both I have a lot of unknown matches. I generated the DNAPainter clusters map, using information generated from ‘AutoClusters’ and ‘Segment info’ on MyHeritage. (Good instructions are given on the DNAPainter site as to how to obtain this information.)

(You need a paid subscription to DNAPainter to have multiple ‘profiles’ or different chromosome maps. A ‘free user’ would have to delete one chromosome map in order to generate another.)

Looking at the results of the ‘Cluster Auto Painter’ tool, when I know how I am related to a match, I can define the cluster including that match as maternal or paternal, and possibly also assign the cluster to the ancestral couple who handed down that DNA.

When all matches in a cluster are unknown to me, I may still be able to define the cluster as maternal /paternal if one of the matches contains an overlapping segment of sufficient size with a match I’ve already worked out. If they appear to lie in the same place on the same chromosome, do the two matches match each other? If so, then they are (probably) either both maternal or both paternal. If it looks like the segments lie on the same place on the same chromosome but the two matches do not match each other, then one must lie on the maternal chromosome of the pair while the other must lie on the paternal chromosome.

Be aware of the threshold (minimum number of centiMorgans to be counted as a match) set on the chromosome browser (eg on MyHeritage). If two segments appear to only slightly overlap there might not be more cM shared than the threshold, so both the matches could be eg maternal but not counted as matching in that location.

I started doing this DNAPainter ‘Cluster Auto Painting’ for my Mum’s matches & could identify almost all her clusters to at least maternal or paternal. Then I used that information in the cluster map created for her brother’s DNA & was able to assign the remaining clusters.

It’s possible there are other connections (between my family and the unknown match) down other lines that I have not yet explored, so “deductions based on deductions” might lead to some errors,  but I have been able to at least provisionally assign my maternal MyHeritage matches to which (of my) maternal grandparents handed down that DNA – and in some cases to an ancestral couple further back.

I don’t know Mum’s maternal grandfather. From Ancestry matches I have identified a few people as definitely on that line. Fortunately a couple of those also have their DNA test on MyHeritage, so I can use this to further define some of the clusters.

The DNA Painter ‘Cluster Auto Painter’ tool does not currently work on Ancestry matches because of the latter company’s not providing matching segment information, but I’m planning to explore how much of the information I work out about MyHeritage matches can be useful in further defining clusters from the other sites that can be input into the ‘Cluster Auto Painter’ on DNAPainter.