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General => Ancestral Family Tree DNA Testing => Topic started by: grahamm684 on Tuesday 06 January 26 21:13 GMT (UK)
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Hi, I have a potential first Half cousin, recently discovered who if its true we share the same Grandad. He was with my Grandmother for a time and they had a son, my Dad, and then he married and had another son who had a daughter.
The only proof was Grandmother's say so which was good enough to stand up in court, and fight off an appeal.
Recently the daughter my potential half first cousin had an Ancestry DNA test, this said she had 4% in the area that her Grandad came from, but I have nothing.
Would you say that this means without any doubt that we are not linked or matched, and that my Grandmother had it wrong.
Kind regards,
Graham
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Hi,
I would say this tells you nothing, 4% from a region, which is a notoriously dubious calculation could easily be zero, or simply someone else who has a link to the area in question.
The real question is what is the cM match between you and your potential first half cousin.
Check using the DNA painter, shared DNA tools, for a little more clarity.
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Hi,
I would say this tells you nothing, 4% from a region, which is a notoriously dubious calculation could easily be zero, or simply someone else who has a link to the area in question.
The real question is what is the cM match between you and your potential first half cousin.
Check using the DNA painter, shared DNA tools, for a little more clarity.
Totally agree. Regional ethnicities at this level are meaningless. However, half 1st cousins share very significant amounts of DNA at ca. 500 cM which would absolutely confirm such a close relationship between you.
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My half 1st. cousins share between 200 and 250 cM with me to give you an idea.
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Try entering your cM numbers here:
https://dnapainter.com/tools/sharedcmv4
It'll give you a better idea of what relationships are likely
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Go by the cM value and that indicates that the Daughter of your probably 1/2 1C should share about 224cM with you, although anywhere in the range is 62-469cM would still be pretty conclusive.
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Sounds to me like Graham may not have done a DNA test himself? Or my not have done an actual comparison to the putative half cousin?
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Ethnicity and regions do nothing to identify ancestors. The overlapping shared dna amounts between full and half cousin matches make it difficult to be certain which is correct when looking at results between two individuals in isolation. More reults re needed to be definitive and in some cases target testing is the only way to be sure.
On paper I have 1c1r matches but the shared dna fits both 1c1r and h1c1r. After target testing their father (on paper my 1c), and finding he shares jut 350cM to me we instantly knew that part of the family are half relatives to me. It also answers why I'm the only one who matches two large group of mystery matches and confirmed my mother is an NPE.
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Well, Thankyou for all your replies, but I am a total beginner with DNA. So I am completely blown away as what to do next.
I did an Ancestry Dna, test and I believe my potential cousin did recently, my results are registered on my tree and have many 1st 2nd 3rd cousin suggestions but not the one I am looking for here. I thought when she had done her test then it would show up with the rest??
Anybody able to expand on a way forward for a beginner??
Cheers!
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Well, Thankyou for all your replies, but I am a total beginner with DNA. So I am completely blown away as what to do next.
I did an Ancestry Dna, test and I believe my potential cousin did recently, my results are registered on my tree and have many 1st 2nd 3rd cousin suggestions but not the one I am looking for here. I thought when she had done her test then it would show up with the rest??
Anybody able to expand on a way forward for a beginner??
Cheers!
Stick with It. I am new to DNA too. A lot here are happy to help. I have found Biggles particular helpful, but others too.
Does the other person's matches show yet? Do you have a number showing the amount of shared DNA between you both, expressed as (for example) 250cM?
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Hi, no I don't know any details other than she told me she had 4% in Calcutta India. That's where her Grandad came from originally, but he is also supposed to have had a son with my Grandmother my Dad.
So when we saw this result I think we both kind of thought that we weren't connected after all.
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As a rule of thumb anyone closer than a 3c will share DNA with you and the child of a half 1c is well within that range, the expected shared dna in such a case would be 62-469cM. How much DNA do you share with this person and do you other shared matches with them?
The first step when dna results come through is to group matches together, many will mention the Leeds method but basic grouping is sufficient. If a batch of matches share dna with each other and also with you that is a group and you will all descend from a common ancestor.
Build the trees of your matches using traditional records to see where the trees intersect, if they don't intersect it suggests there's something amiss in the records, perhaps a child born to an unknown partner, earlier/later marriage or out of wedlock but when registered the details provided were fictitious and simply an attempt to hide the truth. At that point expanding the search and looking more deeply at shared matches really comes into play.
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For the NEWBIES to DNA.
I suggest that you read this thread:-
https://www.rootschat.com/forum/index.php?topic=863488.0
To learn more there is an overwhelming amount of information out there but finding what is useful is very problematic.
You have seen the quotes to use the DNA Painter website, this site is managed by Blaine T Bettinger and the data tools are produced by Johnny Perl.
Blaine has produced a book which I have posted frequently. It is fairly straightforward to follow and if you want to buy another once you have read the above then we can help with a more technical book.
Do note this is the 2nd edition.
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I did an Ancestry Dna, test and I believe my potential cousin did recently, my results are registered on my tree and have many 1st 2nd 3rd cousin suggestions but not the one I am looking for here. I thought when she had done her test then it would show up with the rest??
Did your potential cousin test with Ancestry? If she tested with say Myheritage then you will not find a match.
If you both tested with the same company but there is no match then either:
Your supposed grandad is not the father of your father.
Your supposed father is not your father.
In your matches have you found known cousins on your dads side?
Or maybe your potential half cousin has an NPE in her line.
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I believe she did the test with the same genealogy group as I did but i need to check with her, and also that she registered the test on her tree, which i can't remember if it does that automatically or not.
So if she has completed these things then it would seem I am on the wrong track, would you agree?
Which is disappointing as everything else seems to say we probably are on the right track
Now to find the real Bio Father of my Dad, searching back to 1935, would that be possible using the DNA?? Or is it pretty unlikely?
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DNA matching is just based on the DNA test figures and is not connected to whether a person has a tree or links their DNA to it.
Mabe half of my DNA matches have no tree. That just means that though I can see through shared matches with other known relatives I can see what branch of my tree they are connect with - exactly how they fit to my tree is not possible.
If you have cousins or second or third cousins who have tested then proving your links to your father and his father is quite straightforward. I confirmed that the stepfather of my grandmother was her real father with a DNA match to a woman in Canada who is a second cousin 3 times removed. Our common ancestors are G4 grandparents to me. Since that first match I have found many others confirming the connection.
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I believe she did the test with the same genealogy group as I did but i need to check with her, and also that she registered the test on her tree, which i can't remember if it does that automatically or not.
If it is an Ancestry test it is not automatically linked to a tree.
Nor is it a requirement that any tree has to be created
So if she has completed these things then it would seem I am on the wrong track, would you agree?
Not necessarily, we will need to know how their DNA Match is presented to you
Which is disappointing as everything else seems to say we probably are on the right track
The big issue with Ancestry is being able to identify a DNA Match as many have off user names.
Now to find the real Bio Father of my Dad, searching back to 1935, would that be possible using the DNA?? Or is it pretty unlikely?
Yes it is possible but there is a but.
See answers in your post.
Regarding the Bio Father it is possible but there needs to be a direct descendent having taken or will take a DNA test.
Conversely what we do it to look at say the Siblings or senior relative of the probably Bio Father and work them. They by a process of elimination we often have a situation where a Bio Father can be one of a set of Brothers.
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I have a 40ish cM match 'X' with an unknown ancestor to identify. We have several mutual matches including a grandchild of Frank & Grace at the bottom of the tree (that person is just 15cM to me but 604 to X).
After viewing the dna results of X & building deep/wide trees of his matches then including known the shared matches we have from my own deep and wide tree I've traced 22 matches of X back to the 3 couples at the top of the image (couple 3 are 1st cousins) as follows;
Couple 1; 7 matches via 3 of their children
Couple 2; 8 matches via 3 of their children
Couple 3; 3 matches via a son
The wife of couple 3 had an NPE daughter which links the remaining 4 matches including myself.