Anyone discovered illegitimacies after doing Ancestry DNA? How do you figure it

[brigidmac]

Heb Oops sorry I thought you meant no shared surname matches

No shared DNA matches could also mean her line died out
single children of single children

Or as ruskie said no one in matching lines tested yet

For comparison from a known match
I match my great grandmother legitimate grandson  by 195cm he's my half cousin once removed
Apart from my mother and cousin i only have one other shared match.at 22cm.with him probably via ggmothers Scottish  grandmother
  My cousin does not match same person
So if you get a relative to test you may find different matches

The ggmother in question only had one sister whose children did not have children
She had one illegitimate daughter my nana and I legitimate son father of..half cousin once removed

Unlikely to get other matches unless his half brothers ggrandchild tests .....
But my cousin has 4 shared 4th cousin matches with him which may link back to her ancestors

[Heb66]

H Ruske & Brigidmac,
The puzzle I mentioned is actually from an adoption case I worked on.
I actually managed to trace birth mum via my adopted friends DNA test and now they are happily reconnected.
Birth mum has since revealed who birth dad is, and now we are awaiting the possible half sibling DNA results to come through. No doubt that they will be positive as the family resemblance is remarkable.
The shared match that I mentoned on previous reply is not from maternal line, as I have been able to seperate maternal dna from paternal dna.
Being slightly dense again, am I expecting the single shared match it to show on the paternal line once half sibling results come through.
Thanks for thoughts.....

[brigidmac]

Thats fantastic well done

I dont understand the last sentence tho

Ps ms farrer
The age estimate not always reliable my mums half cousin was my age being from a second marriage and older father

My grandfather had a cousin who was already a father when he was born

[GingerVicky]

Thank you for all your replies. It interesting to hear that some of you have matches with 300 odd cm and can't figure it out.
How accurate do you think the cm measurement is? I have a match with someone who I know I share my 3rd great grandparents, her 2nd great grandparents yet it says we only have 9cm and then i have found others where our shared grandparents are my 17th great grandparents and it says we have 26cm.
All very puzzling.

[guest189040]

Thank you for all your replies. It interesting to hear that some of you have matches with 300 odd cm and can't figure it out.
How accurate do you think the cm measurement is? I have a match with someone who I know I share my 3rd great grandparents, her 2nd great grandparents yet it says we only have 9cm and then i have found others where our shared grandparents are my 17th great grandparents and it says we have 26cm.
All very puzzling.

Where I have 3rd Cousins the DNA cM is about 80-100, your low DNA cM match with a known and proven 3rd Cousin would have me questioning actual bloodlines and also the accuracy of each others DNA test

One of my own 3rd Cousins is 91 cM match, we found each other before we each tested our DNA and have been helping each other for a few years now and already knew where we shared xGGP's.

17th GGP's and 26 cM would indicate to me that there are other links between you and your match that you have yet to find.

Go back far enough and you should find many pathways will exist to get from you to a specific xGGP pair.

As an example my Wife's line goes into the Stanley family and we have found at least three pathways that get from her to a specific GGP pair.  This pair had many children and there are three sons where we can trace a different pathway from each to my Wife, so each son is a xGGP and at the same time an xGUncle.

Sometimes it is worth taking time out and visiting a Tree List and working through it to see if you have duplicates where each of the duplicates leads onto a different branch.

It can take some getting ones head around the xGGP numbers.  What does not happen is that go far enough back and each of your xGGP's will be different, they will not.

If you add up your Grandparents they of course double each generation you go back, get back to about the year 1000 and there will be considerably more GGP's in numbers than there were people alive on the planet (over 2 billion GGP's v a world population of 400M, with 28M being in Europe)

At your 17th GGP level you will have 524,288 people in a tree at that level

I hope this makes sense, it fries my old grey matter at times

[GingerVicky]

Thank you that is helpful. I did think with the one I share a 17th GG that we may relate I  other ways too. I will have to look into that further.
With the 3rd cousin that says we are only 9cm are you saying the DNA is wrong or that our trees are wrong? Could one of our ancestors only be a half daughter of our shared grandparents?
It is hard to get your head round it all.

[guest189040]

Thank you that is helpful. I did think with the one I share a 17th GG that we may relate I  other ways too. I will have to look into that further.
With the 3rd cousin that says we are only 9cm are you saying the DNA is wrong or that our trees are wrong? Could one of our ancestors only be a half daughter of our shared grandparents?
It is hard to get your head round it all.

The DNA Painter cM tool will show the Relationship Probabilities if you enter the cM value of your Match.

The results will give clues as to what you may expect to find.

9 cM returns a 63% probability of one of the following relationships.

6C 6C1R 5C 6C2R 4C1R 5C1R 7C Half 3C2R 4C2R 5C2R 7C1R 3C3R 4C3R 5C3R 8C or more distant

Hence a questionable relationship or faulty tests or a bug in matching software.

PS
A Match with 75 cM will show in DNA Painter as

3C Half 2C1R 2C2R Half 1C3R with a 31% probability

[Romilly]

It’s also important to factor in that a certain percentage of DNA is randomly assigned. By that I mean that siblings matches won’t always concur...

For example, both my sister and my daughter match to people that I don’t, - and visa versa...

My most puzzling match on my Brickwall paternal side matches to myself, sister, daughter, and 3 paternal 1st cousins, - but at widely disparate amounts.

It’s beyond me where he fits in!

Romilly 

[Romilly]

But to reply to the original question, - DNA testing in my family has revealed several cases of bigamy. And so whether that means people were illegitimate is a moot point! According to the paperwork they weren’t.

Romilly.