How to Confirm by DNA when more than one line of connection?

Question

If I have a cousin match within the 3rd cousin range but I have two common lines, both within the 3rd cousin match.  How should I document this?

Comments

What are the WikiTree and GEDmatch IDs for you and your cousin?

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I was asking generically,

I have a lot of overlap with many cousins on my dad's side.  If you are close cousins, chances are you have more than one line of connection.  Most have one cousin within the third cousin range and the second line outside the third cousin range.

I am looking at profiles on Ancestry.com and they show the different connections in common.

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I have been Confirming by DNA my third cousin and closer matches from Ancestry.com and Family Tree DNA where I can find trees to compare.

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I have one cousin with the surname Stills.  But we are not related by the Stills Surname.  William Henry Stills raised Smith Alexander Ricker with his children from which she descends.

I am related to her 6 different ways through her mother (a Ricker) and her father.  But these are in the 4-6 cousin range.  I am related to her though both my paternal grandmother and grandfather.

But that is another challenge for a later time.

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This cousin and my dad share 166.4 cM's as a result.

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I would rather see this all in WikiTree (with pertinent GEDmatch IDs ;-)

So your Dad is in the 3rd cousin once removed range for some of the relationships?

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As far as my cousin's lines go, that is going to be a lot of work which I intend to get to.  I went for the low hanging fruit on my estabilshed direct lines. Yes, I've been doing comparisons to my father's DNA and my mothers.

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I have tried to get my cousin to join WikiTree. But I can add her six lines based on the work she's done on ancestry.com. And I do have her Gedcom ID.  But I felt all that belonged in her purview.

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When you say Gedcom ID, do you mean GEDmatch ID?

Ask her permission and offer for you to add her, her ancestry, and her GEDmatch Id to WikiTree on her behalf.  I've asked over twenty people and all but one or two have said yes.

Sincerely, Peter

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Yes, GEDMatch. Working from mr iPhone. I'll see if I can persuade her again.

Answer 1

Generically speaking regular third cousins share on average 53.13 cM (and very few third cousins will match that average amount).  To feel confident that the ancestry for double third cousins is accurate then they should share a "bit" more than 53.13 cM.  I don't know how much more a bit should be.

Sincerely, Peter

Comments

Ancestry.com does not provide the cM's right?

I need my Ancestry.com cousins to move to Gedmatch or port over to Family Tree DNA to get the cM's.

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Ancestry does tell you the shared cMs in some cases. If you have the little "i" circle next to your confidence level estimate, hovering over that will show you how many cMs in how many segments you share.

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Cool, I missed that. Thanks!

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But I don't think Ancestry tells you on which chromosome you match one another. That information is necessary to confirm relationships further back than third cousin, when triangulation is needed.

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Kay, you are correct. A very good reason to download your raw data from Ancestry and upload it to GEDmatch for any detailed comparisons you may wish to make.  The one to many and one to one tests there are superb and, if you give $10/month, their Tier 1 triangulations are quite good.  I used GEDmatch for awhile as a freebie and finally started contributing for the extras.

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I hesitate to pay for Gedmatch, not that it is not worth the money, I suspect it is, but that it is monthly and to be efficient I need to have a bunch of people ready for testing.

I recently added up the subscriptions I am paying for now and I am easily over $1000 a year, not to mention the one off's I send for.

I need a second job to pay for this hobby or start getting this hobby to be my second job.

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PS, do not tell my wife. I suspect she knows already but we do not need to disturb the force.

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Michael, you can do everything you really need with the free tools at GEDmatch. I only started donating once I realized just how much I was using what I wanted to remain a great online resource. The one to many helps you find folks with whom you are probably related. the one to ones allow you to construct your own triangulations. The match both or either tool is a superb exploration tool. Those are all among the free offerings.

P.S., the wife may already realize, but is probably happy you have found something so fulfilling. Just don't go so overboard that you neglect her.  That way the force stays in balance, too!

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I agree with Phil re: GEDmatch and the force.

Answer 2

Here's an excellent blog on a study of shared cMs using a database of known relationships.

http://thegeneticgenealogist.com/2016/06/26/update-to-the-shared-cm-project/