Autosomal DNA - identify great grandparent?

[melba_schmelba]

I have a mystery ancestor, who was the maternal great grandfather (precisely, mother's mother's father) of my grandmother. Would an autosomal DNA test be likely to turn up anything useful in identifying him?

[davidft]

A lot depends on who you test, this is because autosomal DNA is only good for about 5 generations at most. So if you could test your grandmother there would be more chance than if you tested yourself i.e your grandmother is 4 generations removed whilst you are 6 (4+2). The chances of the test being on you and being successful would be very low

[melba_schmelba]

Thanks for your response . Yes I meant for my grandmother taking the test. But I presume it would then require that mystery great grandfather to have had other children or other siblings who had offspring, otherwise there would be no chance of a match, is that correct?

[davidft]

Thanks for your response . Yes I meant for my grandmother taking the test. But I presume it would then require that mystery great grandfather to have had other children or other siblings who had offspring, otherwise there would be no chance of a match, is that correct?

BIB - yes that is really what is needed and them (or their children etc ) to have tested. Even though its a long shot but people to hit lucky sometimes so good luck.

[melba_schmelba]

Thanks again. Is there any real difference between the ancestry and familytree dna test? Is one more sophisticated than the other? I'm guessing ancestry may be much more popular in the UK, so perhaps more likely to get a match assuming any descendants are in UK? Is there a way to import one's test results into the other's databases?

[familydar]

I'm in the UK and even though it has fewer UK people on its database I chose FTDNA because I didn't want to be tied in to an Ancestry subscription.

I think I read somewhere that FTDNA and Ancestry use the same chipset, whatever that means, but I could be imagining it or that might have changed so don't quote me.  I think that what they're able to test is the same, but they may place different interpretations on the results (in terms of ethnicity for instance, the two companies have differently named areas of the world which don't directly map against each other).

You're not restricted to matches provided by just the company you test with.  You can upload your autosomal results to GEDMatch from different companies (FTDNA, Ancestry and 23andMe plus probably others too).  Also FTDNA will accept (without charge) results from other companies.  As will MyHeritage.

I tested nearly 2 years ago now and if I was doing the same again, I'd still take the same route as I did then.

best wishes
Jane : )

[rsel]

Thanks again. Is there any real difference between the ancestry and familytree dna test? Is one more sophisticated than the other? I'm guessing ancestry may be much more popular in the UK, so perhaps more likely to get a match assuming any descendants are in UK? Is there a way to import one's test results into the other's databases?

Ancestry will probably give you more matches than FTDNA, plus you have the advantage that you can download the results and upload them to FTDNA, and GEDMATCH to take advantage of any matches on those site. if you test elsewhere though, you can't upload your results to Ancestry.

Richard

[Seaton Smithy]

I have a mystery ancestor, who was the maternal great grandfather (precisely, mother's mother's father) of my grandmother. Would an autosomal DNA test be likely to turn up anything useful in identifying him?

I used autosomal DNA to confirm the identity of my paternal great-grandfather, although it helped that I had a suspect in mind (that's him pictured on the left).  I initially got three (now up to five) 4th cousin matches that indicated I was on the right path , and then tracked down one of his legitimate grandchildren who agreed to test with the result being that person shared the right amount of DNA with my uncle for them to be half 1st cousins.

I also confirmed that one of my maternal great-grandfathers wasn't a foundling by comparing two of his grandchildren (my uncle and his first cousin) with descendants of two other lines that would be their paternal 3rd cousins.  That assisted one of the other lines as they had a rumour their grandfather had been the result of an NPE - which I was only told after I had paid for one of them to test!  Now we've confirmed that I hope to one day discover who his mother was.

[melba_schmelba]

I'm in the UK and even though it has fewer UK people on its database I chose FTDNA because I didn't want to be tied in to an Ancestry subscription.

I think I read somewhere that FTDNA and Ancestry use the same chipset, whatever that means, but I could be imagining it or that might have changed so don't quote me.  I think that what they're able to test is the same, but they may place different interpretations on the results (in terms of ethnicity for instance, the two companies have differently named areas of the world which don't directly map against each other).

You're not restricted to matches provided by just the company you test with.  You can upload your autosomal results to GEDMatch from different companies (FTDNA, Ancestry and 23andMe plus probably others too).  Also FTDNA will accept (without charge) results from other companies.  As will MyHeritage.

I tested nearly 2 years ago now and if I was doing the same again, I'd still take the same route as I did then.

best wishes
Jane : )

Thanks for your response Jane I see you can order Familytreedna through the Genealogist, not sure whether it works out cheaper? Findmypast apparently also give a discount but only if you get a years subscription, anyone know how much the discount is?

https://www.thegenealogist.co.uk/dna/
https://www.findmypast.co.uk/first/family-tree-dna

Ancestry will probably give you more matches than FTDNA, plus you have the advantage that you can download the results and upload them to FTDNA, and GEDMATCH to take advantage of any matches on those site. if you test elsewhere though, you can't upload your results to Ancestry.

Richard

Interesting, thanks Richard. If that is the case it seems you have a few more options if you get the ancestry test (I note there's £10 off until the 26th).