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DNA ancestors.

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Evelyn Report 27 Nov 2016 12:41

l have been told that my Gt Gt Gt Grandfather was an illegitimate. l know his fathers legitimate offsprings tree. How can l prove the'hidden secret' through a DNA match. Whose DNA do l need to prove or disprove a connection with? Hope somebody can help.

Thank you


Gwyn in Kent

Gwyn in Kent Report 27 Nov 2016 16:25

Just to clarify.........

You say your 3 x great grandfather was illegitimate, but you know of his father.

Do you mean that he was born of known parents, who were not married to each other?
Did they later marry?


SylviaInCanada Report 27 Nov 2016 19:36

so far as I know, you need the DNA of a known legitimate descendant ....................

and then who do you compare it with on your side?


Maureen Report 27 Nov 2016 20:58

Yes you will need the DNA of one of the Legitimate descendants and your DNA this will show a Match maybe 4th or 6th generation related.

A lady in US tracing her father, knew his surname wasn't until she found the obituary of his grandmother which mentioned her maiden name,the surname had appeared in a DNA match from Ancestry DNA test she had done, same line as my family whose information I had, we were able to thus prove he was her father, sadly didn't end well but she is in contact with aunts and cousins.


Evelyn Report 28 Nov 2016 10:51

l cannot trace his mother or father. It has been covered up What l want to know is who can carry out this genetic test for me, who is the most reliable. as his father might have been one of 2 brothers. How could l test this? Do I follow both lineages and if l did and managed to get a test done, Would a test from both lineages be able to prove a certain more likely match, connection and would they be able to determine who the actually parent was? i.e. one match being better than another?? I might need help in determining the best offspring to try and match with? Thank you for any help.


SylviaInCanada Report 28 Nov 2016 18:27

No, you do NOT get an exact match .......

....... you're testing descendants and their genetic make-up will vary because of the half of the DNA contributed at every generation by the parent not of the line.

I've read somewhere that these tests are accurate only up to the first or possibly second cousin, then become less and less accurate.

and,anyway, just how are you going to get a descendant of one of those 2 potential ancestors to donate their DNA? Not many people like to be told that there illegitimate offspring wanting to join the family.


JoonieCloonie Report 2 Dec 2016 02:41

First, you definitely have to have someone from each line.

If you have a male-line descendant in each line, that is the perfect situation.

That is, a son of a son of a son ... of your grx3 grandfather.
And the same in the other family.

That is because male-line DNA -- YDNA -- is passed from father to son almost unchanged. You would actually get an almost-perfect match if the two male-line descendants, in each line, were descended from the same man. In that few generations, there might have been a slight mutation in the YDNA, but it would be essentially identical.

Mothers pass mitochondrial DNA -- mtDNA -- to all their children, but only their daughters pass it on to their children. So this would not help you, because your grx3 grandfather did not pass on his paternal grandmother's mtDNA.

The third option is autosomal DNA -- atDNA -- and that can identify cousins, sometimes up to fifth cousin level. Fifth cousins share grx4 grandparents. This is what Ancestry tests.

For all of these options, it is best to test the oldest available people, since the closer they are to the common ancestor, the better the match will be.

I recommend Family Tree DNA (FTDN) for testing. There is a lot of support available there, through projects and help forums, that just isn't at Ancestry. Autosomal DNA matching can take some figuring out -- I haven't tried it yet -- and you would be able to get lots of help.

FTDNA has its Holiday sale on.

Family Finder -- the same kind of test as Ancestry does, autosomal DNA -- is on sale for $59 regular $99 USD.

YDNA 37 markers - the place to start for YDNA - is $139 on sale from $169 USD.

(If you have a reasonable match at 37 markers, you can upgrade to 67 to see whether the match holds up. The closeness of matches will *decline* with a greater number of markers tested, since other mismatches will appear.)

If you can rustle up male-line descendants to test, YDNA is the thing to do.

If not, autosomal DNA (FTDNA Family Finder, or Ancestry's test) is the other option.

But I strongly advise using FTDNA not Ancestry.

I have used FTDNA for YDNA testing on both sides of my family, and had the stupendous luck of a very close match on my mother's side ... that threw a wrench into my brick wall. :-)

Both autosomal and YDNA testing could find relations you don't know about too, keep in mind, who could turn out to be related to your grx3 grandfather's father. FTDNA does the matching for you for both kinds of tests.


SylviaInCanada Report 2 Dec 2016 03:32


but doesn't getting matches depend on others having done the test??

So Evelyn will have to find and persuade descendants of all 3 lines to test ................ somehow


JoonieCloonie Report 2 Dec 2016 04:56

It does, Sylvia, there has to be someone to match with :-)

But I don't understand the three lines you mention. Oh, I see, the father could have been one of two brothers.

Well, for YDNA, it wouldn't matter -- although it would not pinpoint which brother, a close match would confirm it was one of them or someone else very closely related (e.g. a paternal uncle's son).

An autosomal match also would not pinpoint which brother, it would just give an indication of the degree of relationship to the other person who tested, and what it would do is indicate where the common ancestor was -- which would be your grx4 grandfather in any case.

Keep in mind that at that distance, you are talking about 5th cousins, and that is the outside limit of meaningful matches. Again, best to test an older generation if you can.

So Evelyn needs someone in her own line (herself in a pinch, but preferably her parent or grandparent) to do the autosomal (Family Finder) test.

And then she needs someone in the other line (from her grx3 grandfather's putative father) who will also do an autosomal test. And yes, I see now, someone from both the potential fathers' lines. Although again, if you are so lucky as to find male-line descendants, it won't matter -- and it won't tell you which brother, no matter whether you test one or both lines, almost certainly, because their YDNA would almost certainly be identical.

So the preferable alternative (because distance from the common ancestor is not nearly as significant): someone in her own line who is a male-line descendant of her grx3 grandfather -- his gr-grandson or grx2 or grx3 grandson -- who descends from the grx3 grandfather through the male line (which usually means having the same surname as the grx3 grandfather).

BUT the YDNA matching only works if there is a male-line descendant in the other line (descended from the grx3 grandfather's father, or that man's brother or father or paternal uncle ...) who will test.

If, for instance, you descend from your grx3 grandfather through your mother, then to find a YDNA candidate you would have to trace up the tree to a male descendant of your grx3 grandfather and back down again, if necessary, to some kind of male cousin.

Autosomal testing works for everybody, male or female. So you would just need somebody descended directly from one of your grx3 grandfather's putative fathers, and somebody descended from your grx3 grandfather (like you).

I am not up enough on autosomal DNA testing to know whether it would likely distinguish between the two brothers, honestly. But that is putting the cart before the horse; first you need a match! And at FTDNA there are all kinds of people who can answer questions like that.

However, the thing with the databases is that a match could be made with a stranger you know nothing about, who could turn out to be descended from your grx3 grandfather's putative father, or uncle or aunt. A descendant of his father's brother would have the same YDNA, a descendant of his father's sister would share autosomal DNA (but that would be getting so far back that you would want to test the oldest possible generation of your own family).

I can share all kinds of tips and tricks about maintaining privacy and confidentiality at Family Tree DNA, if you go that route. No one's identity need ever be revealed unless they want to.

I can also try to explain any of this that has left your head spinning. :-D


JoonieCloonie Report 2 Dec 2016 05:05

Just one other thing ... some years ago, I helped an elderly gent in Australia, born in England in the roaring twenties to a factory girl, find out who his father, the owner of the factory who he had been told was killed in a crash in his red convertible, was. Turned out he was a titled young man, and he was quite alive for quite some time.

The young man had settled down after the 1920s and taken his proper place in the professions and the landed gentry in Ireland, and produced children.

The Australian man contacted them, and was indeed welcomed into the bosom of the family by his half-siblings. He travelled to meet them, and they sent me photos!

Not everybody is going to be very concerned that their grx4 grandfather was indiscreet. :-)

(On the other hand, it isn't always indiscretion. My great-aunt's father is unknown, except for the surname she bore as a middle name. She resulted from exploitation of my gr-grandmother by the young master of the house where she was a servant. It would not be terribly unusual for a child to be born as a result of such exploitation, or assault. But looking back that far, it's unlikely to ever be possible to know.)