Wednesday, March 18, 2020

Dear Randy: What Do You Add To Your Family Tree For DNA Matches?

A society colleague asked this question - "What Do You Add To Your Family Tree for DNA Matches?" - several months ago in a Research Group meeting.  I wrote it down and lost the paper.  I found the paper today!  Now I remember...

My response in the meeting was:  "It depends" (hi Judy and many other genealogists!).  

1)  For DNA matches with less than 15 cM, I don't do much, since most don't have an online tree, or shared matches, unless they have an AncestryDNA ThruLine or a MyHeritage Theory of Family Relativity.

2)  For DNA matches with more than 15 cM, I try to determine which family line they may be in, using Shared Matches (or similar features) on AncestryDNA, MyHeritage, 23andMe and FamilyTreeDNA.  I also use Genetic Affairs and Shared AutoClusters to see if those tools help identify a common ancestor.

3)  I make Notes on the DNA site for these matches, noting how much DNA is shared, how many shared matches they have, which family line they may be in, and which common ancestors we share.  A typical note with a ThruLine, Theory, or known family line will say:

"4C1R - in RM - 22 cM in 2 segments - private tree (9 people) - many shared matches - has a  ThruLine, common ancestors are 3rd great-grandparents Abraham Kemp and Sarah Fletcher"

If there is no ThruLine or Theory, my Note might say:

"55 cM in 1 segment - unlinked tiny tree, some shared matches, probably a #Carringer, #Feather or #Spangler connection, no VRs in tree"

4)  If a match has an AncestryDNA Thruline or a MyHeritage Theory of Family Relativity, I look at the ThruLine or Theory and investigate it, one link at a time looking for inconsistencies (dates, places, etc.).  

5)  For matches with more than 15 cM and a ThruLine or Theory, I enter the suggested line into my RootsMagic family tree with the approximate dates and places for birth, marriages, and death obtained from my investigation.  When I TreeShare the new persons added to my RootsMagic tree to my Ancestry Member Tree, the Ancestry Hints appear almost immediately, and information from reliable sources are added to substantiate the names, relationships, dates, places, etc.  I then do a search on Ancestry, MyHeritage and Findmypast for additional reliable information, and add that to my RootsMagic profile with sources (which when TreeShared may find additional records on Ancestry). For 80 to 90% of these additions, I can find a parent-child relationship, a spousal relationship, and birth, marriage and death entries in what I consider reliable and authoritative sources.  Sometimes, it takes awhile - more than a few days, say.  This applies mainly to persons born after 1800, but that's where we find most common ancestors of our DNA matches.

6)  Sometimes, there is not enough information in the ThruLine to reliably add the match's line down to the DNA Match because of Private people in the ThruLine or an obvious error in online family trees.  I still have a DNA Match with that person, but it may not be on the ThruLine or Theory provided.

7)  When I am fairly sure that the information I have used is substantiated, I add a DNA Match event to the DNA match's profile in RootsMagic.  There are four inputs to this event - a typical DNA Match event would have:

*  Description:  "AncestryDNA, 22 cM in 2 segments, 4th cousin 1x removed"

*  Note:  "xxxxx xxxxx is an AncestryDNA match with Randall Seaver, sharing 22 cM in 1 segment.  They are 4th cousins 1x removed with common ancestors of 3rd great-grandparents Abraham Kemp and Sarah Fletcher."

*  I mark this Event "Private" on the Edit Person screen of the DNA Match.

*  I add the DNA Match's name to the "AncestryDNA" QuickGroup in RootsMagic, and also identify the match as a descendant of a known ancestor.  For instance for this match, I identified him as a "Descendant of John Kemp UEL 1723."  I can make QuickGroups easily, and try to start them with 5th great-grandparents or earlier ancestors.

8)  What about DNA matches with less than 15 cM and a ThruLine or Theory?  I add some of those using the process above, but they often do not have a complete and substantiated ThruLine.  It's a judgment call on my part.

9)  I hear readers thinking "But how do you know they are right?"  Several of my society colleagues asked this question too.  I don't.  I don't know that everything in my RootsMagic tree, or in other Ancestry Member Trees, or in Geni, WikiTree and FamilySearch Family Tree, is right.  I find mistakes in typing, data entry, and data analysis almost every day because I am human.  But I like to think that I am generally objective, experienced, can judge the veracity of information, and don't have an agenda.  However, these are DNA matches with me, and, according to many of the experts I read, if I share 15 cM or more, then we are cousins in some family line with one or more sets of common ancestors.  It's my tree, and you don't have to agree with what I do or how I've done it.  If I am presented with different information and judge that it is better than what I have already, I will change my individual tree profiles to match the best information possible, even to the extent of detaching children from parents or a person from a spouse who doesn't "belong" to them.  It's definitely a work in progress!!

10)  What do you do in your family tree with your DNA matches?


Copyright (c) 2020, Randall J. Seaver

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