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General => Ancestral Family Tree DNA Testing => Topic started by: Spidermonkey on Tuesday 26 May 20 14:12 BST (UK)

Title: Shared matches (Ancestry DNA) question
Post by: Spidermonkey on Tuesday 26 May 20 14:12 BST (UK)
In these long lazy days of lockdown I have been going through my dad's Ancestry DNA matches, looking at common ancestor matches and then using the colour coding function to put them into groups.  I'm then using the shared matches function to identify other DNA matches whose trees don't have a common ancestor featured.

What I have found is that I have several DNA matches each of whom match my dad at 3x gt grandparents (so 4th cousin 1 x removed level), but who don't match each other - is this a normal thing when the connection is so far back (and only match on c. 8cM)?
Title: Re: Shared matches (Ancestry DNA) question
Post by: Gadget on Tuesday 26 May 20 14:18 BST (UK)
The matches of shared matches only show up if they share 20cM or more with the shared match (if you see what I mean).

Title: Re: Shared matches (Ancestry DNA) question
Post by: Spidermonkey on Tuesday 26 May 20 14:22 BST (UK)
That makes sense, Gadget, thank you.
Title: Re: Shared matches (Ancestry DNA) question
Post by: Spidermonkey on Friday 29 May 20 11:19 BST (UK)
Ok, next novice question!

As per my first post, I have been trying to group DNA matches so that even if I can't immediately find a shared ancestor, I at least know what line they are likely to be part of (this is mostly because I have some questions as to the father of a gt gt grandfather).

I've got a match with whom I have no identifiable shared ancestor, but when I use the shared match function on Ancestry, then I have 20 or so shared matches - far more than on any other shared match.  Some of these people have extensive family trees, but I can't find a shared ancestor on those either.  Is there a function where Ancestry can compare all the trees of my shared matches to see if there is a shared ancestory on their trees? 

And if not, is there a way of doing the above function that doesn't involve me printing off their trees and cross matching by hand?

Thanks,

S
Title: Re: Shared matches (Ancestry DNA) question
Post by: Craclyn on Friday 29 May 20 12:10 BST (UK)
Ancestry does not have a function to report potential shared ancestors that appear in the trees of your shared matches, other than the limited information you can get from ThruLines. There are several third party tools which can give you this information, but some of them are struggling a little at the moment following a recent change in the interface with Ancestry that makes the extraction process very slow. Some tools that you can consider include Genetic Affairs, DNAGedcom and DNA2tree.
Title: Re: Shared matches (Ancestry DNA) question
Post by: guest189040 on Friday 29 May 20 12:25 BST (UK)
I am going through my DNA results but at present only those with a Common Ancestor.

What the thru lines is showing is people who may not necessarily be on the tree of the person who you are trying to link to.

It seems that the Ancestry is using all trees to piece together a possible path and they hedge their bets by including Evaluate in the box of each person where there is not a contiguous link.

I to use the grouping function and gave created a custom group labelled Linked which I apply to the person whose DNA I share, I only check this box when I have a proven link and included them on my own tree.

Where there is no listed Common ancestor is a needle in a haystack unless a their surname or a surname somewhere in their tree rings a bell.

I am trying to link an to an Ainsworth who is not in my tree yet it is a family name but going back to the mid 1700’s is not yielding any joy. 

Such are the trials and tribulation of our research
Title: Re: Shared matches (Ancestry DNA) question
Post by: IgorStrav on Friday 29 May 20 12:38 BST (UK)
Hi Spidermonkey

I fear I must introduce you to the frustrations of DNA, where - if you're like me - you will have numerous matches, with numerous shared matches of their own with you, who don't pop up with any names at all you recognise.

Some will have trees of several thousand people, and you will open them in great hope and find that you STILL can't see any names you recognise.

This isn't to say that you can't pin down links, and satisfactorily group matches where they 'must' go.

However, as someone who has more than one 100cM+ mystery matches, you may not get further.

Not meant to discourage you.  But it does seem to be how the 'miracle' DNA seems to work so far for me.
Title: Re: Shared matches (Ancestry DNA) question
Post by: Craclyn on Friday 29 May 20 12:42 BST (UK)
In the half hour since I made post #4 above, Genetic Affairs have announced that they have had a notification from Ancestry legal representatives telling them to cease and desist pulling information from the Ancestry database. Quite possible that the other third party tools will also soon be shut out.
Title: Re: Shared matches (Ancestry DNA) question
Post by: Gadget on Friday 29 May 20 12:49 BST (UK)
What I have done in similar situations is to work from the original list of shared matches and then iterate through them doing a shared match run with each on the list. You might then be able to get smaller groups. Maybe then use the colour coding facility for each new group. Some might have multiple colours and some might not, which could give more clues.

I also check there trees thoroughly. Many mistakes can be made. Look for locations that might match as well.  I have re-created their trees in many cases.

Gadget
Title: Re: Shared matches (Ancestry DNA) question
Post by: Spidermonkey on Sunday 31 May 20 14:47 BST (UK)
Apologies for not replying sooner - I have spent the weekend trying to untangle my back garden (previous owners used the back corner of the garden as a rubbish tip, and seemingly when the tip got too tall they strapped it down with chicken wire, before loading it up again.  I am now covered in scratches from brambles and rusted wire - fortunately tetanus is up to date!)

I have been building some trees, and having some joy that way - often with locations rather than surnames.

The vast majority of my matches are at 4th to 6th cousin level (as per Ancestry terminology) - I have one match at 3rd cousin level, but the rest are more distant.  By the time one gets to 3 x gt or 4x gt grandparents, the scope for errors and non-paternal events are quite high.

But hey ho!  It's all part of fun!!  Thank you all for your comments and contributions.