* MCRA query for more than one person

[ltester]

I have tagged the people who I've matched on DNA and would like to construct a query which allows me to see the MCRA of each of them in relation to me, the file root, in one query, without having to go through them all individually. I'm not skilled enough to work out how to do this. Does anyone have any ideas that I could try out please? Thanks!

[tatewise]

I presume you mean MRCA ~ Most Recent Common Ancestor.

I don't believe it would be possible to use a Query to produce that kind of relationship.
You would need to write a custom plugin.

You could use the Tools > How Related... command, select one DNA tagged person and the file root person, then choose Display Graphically... > Hide Spouses & Siblings to show the relationship via the MRCA.

This webpage https://dna-explained.com/2012/08/06/wh ... ally-mean/ suggests that both Family Tree DNA and Ancestry.com offer MRCA reports.

[RS3100]

2nd attempt at replying as I'm on a ferry at the moment with poor bandwidth and unreliable connectivity.

I use Jane Taubman's custom GEDmatch fact and associated query for recording DNA matches. The query result shows the MRCA(s) for each match along with the match's relationship to the primary DNA test (you?) which may be what you want. You can sort all matches through a particular MRCA or couple by selecting the appropriate column to change the sort order in the result set,

There is a link under the DNA section of the knowledge base AFAIR, and more information on Jane's own website, also linked I think. Even if you don't want to use it as is, it may give you some ideas. I have customised it slightly to suit my requirements.

[LornaCraig]

In case you are not aware, there is also an existing basic custom query which finds the MRCA for a selected pair of individuals. However it works with only two starting individuals, and in the results the MRCA (or two, if they are a couple) is/are displayed on separate row(s). So it’s not as versatile as the query RS3100 has referred to.

It can be found here Most Recent Common Ancestors (it does work with V7, although the page doesn't say so.)

[ColeValleyGirl]

It can be found here Most Recent Common Ancestors (it does work with V7, although the page doesn't say so.)

It does now, Lorna

[sbell95]

I am also interested in this as I have chosen to use flags for my DNA matches as opposed to Jane's DNA fact and accompanying query.

One thing I have been able to achieve is a text scheme expression for my boxes which includes the relationship between a DNA match and the test-taker, though this doesn't include common ancestor information. When displayed in a diagram, though, it is easy to navigate up/across the tree to see where our ancestors intersect. See below a redacted example:

Screenshot 2023-03-27 114817.png (24.24 KiB) Viewed 468 times

I suspect a query based on flags doesn't work as the common ancestors are 'hard coded' into the DNA fact and so can be queried and returned in a result set. Without that information, I don't know if there is a FH function which could automatically return the common ancestors... but I wait with bated breath to be told otherwise by someone with more experience in queries and plugins!

[LornaCraig]

I suspect a query based on flags doesn't work as the common ancestors are 'hard coded' into the DNA fact and so can be queried and returned in a result set.

In this case the flags (if that is what the OP means by having ‘tagged’ people) are just being used to indicate people with a DNA match, so they can be used to add people to a Named List. The requirement is then for the people in that list to be entered simultaneously in a query.

To display the results for a whole list of people each person would be need to be in one row of their own, and their MRCA with the root person would be displayed in a column.

But, as the query I referred to previously shows, the MRCA is calculated by adding and excluding specific sets of ancestors using the row filters. This means that the resulting set (which contains one, or a couple, of people who are the MRCA) is displayed on a row (or two rows). This I why the query can only handle one comparison at a time.

The other problem, of course, is that the MRCA of any two people may be someone who is not recorded (yet) in your project at all. In that case all you have to go on is the estimated degree of relatedness suggested by the DNA results.

[RS3100]

It is also possible for the primary tester to be related to a DNA match through more than one MRCA, singular or couple. I have quite a few instances in my own tree of being related to matches via two or three different MRCAs, due to pedigree collapse in small rural communities. The built-in "How Related" tool in FH will indicate that, but only if the individuals involved are already included in the tree. Sometimes I have only discovered it whilst investigating matches and their ancestry to corroborate what Ancestry's hints or similar suggestions from other sites are indicating to me, or whilst expanding collateral lines between us.

I'm not sure how you could record that solely through setting flags. or indeed the details of the matches such as total shared DNA, largest and number of matching segments, etc. All of which can be useful comparisons between matches related to each other through the same branch of the family, and when investigating other matches where the exact relationship is not immediately apparent.

Using Jane's GEDmatch fact, I create a separate fact for each relationship, so where for example I have a match to another individual via three possible sets of MRCAs, that individual has three GEDmatch facts for their relationship to me, each specifying a different one of the three MRCAs and the relationship between us through that route. That information is also readily apparent in the query result set. I also use one type of DNA icon in charts for matches to our primary tests (myself, my brother or my cousin) and a different DNA icon to indicate the MRCAs with whom our matches are shared, and another icon to indicate which one or more of the three primary tests are a match to each individual.

Of course, where any of the primary tests appear to be related through more than one MRCA singular or couple, it could be that the actual match might only be via one of the possible lines. But in the absence of triangulation and exact shared chromosome positions which might enable the route to be corroborated, all possibilities have to be assumed.