Ancestry Assignment to Both Sides

[LizzieL]

I too have some both side.

The are 16 DNA matches who are in this class, highest is a mere 21cM with Zero shared match’s.

My Paternal and Maternal lines are from very different parts of England so the probability of this happening in my case in recent times is in any case very, very low.

Using the Gedmatch “Are My Parents Related” tool produces a NO.

As I said a few replies ago, your parents don't have to be related for you to have a "both sides" match. You just need to have a cousin on your father's side to marry a cousin from your mother's side and produce a child. That child would be a both sides match to you.

You say the probability in recent times is low. But people were much more mobile in the 20th / 21st century. Servicemen and women moving around in wartime and more recently people moving long distances from their birthplace for jobs.
My mother was in WRAF in WW2. came from very south of Hampshire. Was posted all over UK even as far north as the Orkney Isles. She could easily have met a man and married him in any one of those places. Neither she nor her two sisters married a man from their home town. On the other side of the family, two aunts in the ATS from Berkshire married husbands from Liverpool and Devon, also in the services.
Going further back to 1920 (and this took a bit of finding because the Smith surname was involved) my 1C1R from Portsmouth married a man from Durham. We discovered he had briefly (between censuses) been a sailor (merchant navy) and met her in Portsmouth.

[LizzieL]

I would agree that the majority of the both sides that Ancestry has assigned are spurious. My genuine both sides that I found, and Ancestry didn't, is only 16cm/ 1 segment, unweighted 25, longest 25cM

[ikas]

Thanks again all for your info. I am now convinced this update is spurious. I will report as such to Ancestry support. Let you know if I get a response.

[Biggles50]

I too have some both side.

The are 16 DNA matches who are in this class, highest is a mere 21cM with Zero shared match’s.

My Paternal and Maternal lines are from very different parts of England so the probability of this happening in my case in recent times is in any case very, very low.

Using the Gedmatch “Are My Parents Related” tool produces a NO.

As I said a few replies ago, your parents don't have to be related for you to have a "both sides" match. You just need to have a cousin on your father's side to marry a cousin from your mother's side and produce a child. That child would be a both sides match to you.

You say the probability in recent times is low. But people were much more mobile in the 20th / 21st century. Servicemen and women moving around in wartime and more recently people moving long distances from their birthplace for jobs.
My mother was in WRAF in WW2. came from very south of Hampshire. Was posted all over UK even as far north as the Orkney Isles. She could easily have met a man and married him in any one of those places. Neither she nor her two sisters married a man from their home town. On the other side of the family, two aunts in the ATS from Berkshire married husbands from Liverpool and Devon, also in the services.
Going further back to 1920 (and this took a bit of finding because the Smith surname was involved) my 1C1R from Portsmouth married a man from Durham. We discovered he had briefly (between censuses) been a sailor (merchant navy) and met her in Portsmouth.

Yes, but I am not talking about the 20th century, especially with a match of only 21cM as that is probably the result of a joining in the early to mid 19th century.

At that level the highest probability is in the 4C range or at my 3xGGP.

All my 3xGGP except I were fairly static and the one that was not has a lot of descendants but the 21cM has no shared match’s with this 3xGGF line so that skews the though process.  If this changes then I shall revisit my views.

I have compared my Wife’s DNA to my own with no shared segments the results and given that within the last four generations there has been no interaction between our families which is not surprising since we are from Cities 70 miles apart.

On Ancestry we do have shared match’s with each other so as you say Cousin marrying Cousin but in our cases that is likely to be 200+ years ago.

[LizzieL]

Why would the marriage event need to be so long ago?
My genuine both sides match is 16 cm, the marriage which joined the two lines took place in 1901. But it could easily have been more recent. The match is my 3rd cousin on my father's side and my 5C1R on my mother's side. I am surprised it is so low a match. The 3rd cousin relationship is by being great grandson of my great grandmother's sister. I have a 34 cM match with a 3C1R, the 2 x great grandson of the same sister, and a 62 cM match with another 3C1R, the 2 x great grandson of another sister of the same great grandmother.
Painter predicts a much more distant relationship for my 16 cm match, more in line with the 5C1R alone. But if it wasn't for a good paper trail and 9 shared matches to descendants of that great grandmother's parents I might doubt the 3C relationship
Isn't DNA  wierd 

[TonyV]

I now have 4 Both Sides matches where previously I had none. Two of them share matches exclusively with my paternal side, one exclusively with my maternal side and one with both sides. My mother comes from a well-researched English line that lived and bred in the English Midlands going back to the mid 1700s. My genetic father was an Irish American who went to the USA from Co. Mayo and didn't go to England until the war.

It is very very unlikely that I have both sides ancestors based on the timescales of autosomal DNA accuracy.

[Petros]

I've just seen these on my wife's profile. One of the 5 such matches shares a common ancestor on her paternal line, albeit at the 5C level

[Sinann]

My sister is showing as 50 Both Sides, I’m showing as having 37
I searched my sisters 50 on my list and apart from each other, her daughter and another niece I found 5 we both have, a 20cM a 15, 13,11, and 9. No idea how any of the 5 match on either side.

Our 1st Cousin has 26 both sides I found 1 who matches with me, none with my sister.

[Petros]

Descent on both sides is certainly something that occurs but many such matches would probably be too long ago for Ancestry to recognise them. My wife and I are descended from the same couple born 1751 and 1760, my 4 x GGPs her 6 x GGPs, but we don't show as a match to each other (ca 4 cM using GEDMatch).

Perhaps more such cases are when the descent is from a small population (village) where there were a number of events over the years