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General => Ancestral Family Tree DNA Testing => Topic started by: MikeR48 on Saturday 07 December 19 18:12 GMT (UK)
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Hi all, old dog new tricks springs to mind here, :)
I have 2 matches... BP.. 104 cm over 7 segments & ..MA ...26 cm across 3 segments who are 3rd cousins to each other according to our well documented trees, and we have all conversed with each other pre dna, their GG grandfather is my G grandfather, when I do a shared match with these they both match with me but not with each other and only MA matches with my nephew. Can someone please
explain to me what is going on here, or am I missing something.
Mike
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when I do a shared match with these they both match with me but not with each other and only MA matches with my nephew.
Do you match with them both at the same point or at different points?
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I'm not sure how I would know that. :-[
Mike
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I'm not sure how I would know that. :-[
Mike
What site did you do the tests with? If its not one that gives these details (eg FTDNA, Gedmatch, MyHeritage etc) then you would not know and that is part of your problem.
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Thanks for your input. Ancestry...and have uploaded to the other sites, but one of the others hasn't.
Mike
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OK
The reason I asked is that the sites I mentioned have a chromosome browser but Ancestry does not.
You say one of the matches has not uploaded to a site with a chromosome browser, this is a problem and you need to persuade them to do so if you can.
What a chromosome browser does is show where you match on each chromosome with each match. Given the scenario you mentioned above I would be expecting the chromosome browser results to show where you match with the two matches but that they do not match each other at the same point. This is perfectly in order with all three of you still being related via your G Grandfather.
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You all got different segments of DNA from your common ancestors. At 3rd cousin level, not everyone will show as a match. These statistics indicate the probabilities: https://isogg.org/wiki/Cousin_statistics (https://isogg.org/wiki/Cousin_statistics)
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Thank you both for your replies, I have learnt something today ;D
Mike