DNA and 'Common Ancestors' on Ancestry

[JohnR65]

I've been working through my list of 'unviewed' DNA matches that show Common Ancestors. Invariably, these have no trees, private trees or trees with 3 people on them! However I then find their Common Ancestors which takes me to Thru Lines and 'alleged' ancestors -some of these I agree with but others I have no knowledge of, so I have researched further the ones I know of down to the new cousin which works great. Sometime though they are not contactable which is frustrating to say the least.
The problem is this, can I believe the Thru Lines trees that show an ancestor I'm unaware of? This is particularly hard when records are before 1837 and difficult to check.
Do people add trees that are not properly researched so that I appear to have a spurious ancestor or does the DNA match override that?
Makes my brain ache!

 

[Pauline]

The problem is this, can I believe the Thru Lines trees that show an ancestor I'm unaware of?

No, not necessarily.

Do people add trees that are not properly researched so that I appear to have a spurious ancestor

Yes.

or does the DNA match override that?

No.

ThruLines offers hints, and like all Ancestry hints they have to be fully checked out. Checking for shared matches can help to determine if the suggested Common Ancestor(s) is at least in the right part of your tree though this doesn't necessarily mean the common ancestor hint is correct.

Some of my suggested distant common ancestors may be correct but there is insufficient evidence to confirm if they are or not. Lots of trees may have assumed the link, but without providing any evidence to back it up. I also have at least one common ancestor hint where the suggested common ancestors are actually correct but the route taken in the supporting trees to reach those ancestors isn't.

 

[JohnR65]

It's a minefield!

 

[Kate]

I have just looked through mine. One match is being 'attached' by thrulines to a person who died young and, as far as I know, had no children. I am sure their ancestor should be attached to a different person, a few years older, in the same place, with the same name. I would not trust thrulines without satisfying yourself that it is right. By the way, I have 'proved' a line by down loading the supposed father's will and checking the names of his children and husbands/wives.

 

[Mitch_in_Notts]

Yet again last night a new Common Ancestor DNA match for my Dad - Shows our James RUSSELL 1812-1851, as the Son of Margaret CUTHILL b1792. Over 20 years ago when I started out I added Margaret CUTHILL as the Mother of James RUSSELL, (based on research that my Uncle had paid for in the 1980s that I now know to be well dodgy) - I quickly got a message on Genes Reunited to say Margaret CUTHILLs Son James RUSSELL was born in 1822(Scotlandspeople confirms it) not 1812 and died in Canada so cannot be my James RUSSELL! I corrected my tree unlike many other people. Common Ancestors regularly throws up this anomaly. I still don't know who my James RUSSELLs parents are. or the connection to all these DNA matches!

 

[peter]

Pauline is spot on - ThruLines and Common Ancestors are hints. But Common Ancestors is generally pretty reliable because it's rooted in DNA, not just trees.
Though there may be a problem at the moment as I got a crazy result for one of my matches.

 

[Susan48]

But Common Ancestors is generally pretty reliable because it's rooted in DNA, not just trees.

Sometimes a suspicious-looking pair of Common Ancestors can lead you to a more likely pair. One of my brick walls was my 3 x gt-grandmother Susanna Banham whose baptism I couldn't find (and still haven't found). According to the 1851 census she was born in Dedham, Essex, and needed the permission of her parents when she married in 1813 so this would put her birth after 1794. The witnesses at the marriage were William Banham and Mary Vale (the groom's mother). Ancestry recently suggested a common ancestor with the surname Bunton for one of my matches. Bunton could be a variation of Banham but I wasn't convinced so investigated the tree of my match and did indeed find a Banham but on a different line to the one Ancestry had suggested. To cut a very long story short, after a lot of research I did find a pair of common ancestors that could have been William Banham's parents and thus Susanna's grandparents. After adding these two generations to my direct ancestors tree linked to my DNA results I had a lot of matches sharing these same common ancestors. William was one of many children born to his parents, and all his siblings seem to have had large families. I have DNA matches with descendants of many of them, but they are all below the 20cM mark so don't appear as shared matches.

The bottom line is, that if Ancestry hadn't suggested the wrong common ancestors, I would not have found the right ones.

 

[peter]

needed the permission of her parents when she married in 1813 so this would put her birth after 1794

If she was under 21 at the time of her marriage that would put her birth as 1792 or later, not 1794.

 

[Susan48]

All right, I stand corrected on my arithmetic. Her death certificate in 1857 states she was 63 which would put her birth at around 1794 but I suspect she was born a year or two later.

 

[peter]

All right, I stand corrected on my arithmetic. Her death certificate in 1857 states she was 63 which would put her birth at around 1794 but I suspect she was born a year or two later.

The reason I pointed out the discrepancy was because some younger members might have incorrectly deduced that 18 was the age of majority, whereas it was 21 until 1969.

 

[JohnR65]

I have a Thru Line DNA match to one of my ancestors allegedly but looking at the tree they appear to have mixed up the names of the ancestor insofar as they have her married but she died a spinster. The person responsible is not actually the tree owner but an amateur 'researcher' for many trees. I even got a copy of the marriage cert for them but they still do nothing. So there are now 2 DNA alleged matches to me that aren't in reality!

 

[peter]

I have a Thru Line DNA match to one of my ancestors allegedly but looking at the tree they appear to have mixed up the names of the ancestor insofar as they have her married but she died a spinster. The person responsible is not actually the tree owner but an amateur 'researcher' for many trees. I even got a copy of the marriage cert for them but they still do nothing. So there are now 2 DNA alleged matches to me that aren't in reality!

ThruLines are, like Common Ancestors, hints based on Ancestry trees. The fact that the trees are wrong does not mean that you are unrelated to your match, only that you are not related in the way that Ancestry have inferred from looking at users' trees.

DNA provides a cross-check on the wilder excesses of incompetent 'researchers', but it cannot compensate for all of their errors. The best thing you can do is what I do: post polite and informative comments against the incorrect tree entries (which you are likely to find appear in multiple trees). Sadly most people who complain about other users' Ancestry trees don't take this simple step, which will warn others who might - through inexperience, lack of time, of deficit of scepticism - believe what the tree says.

 

[Tim]

I have many examples where Thru Lines suggest a link to my DNA match but the trees they provide don't match. It seems to be a case of trees and or close name matches, which means as Peter has pointed out, we're connected along a different path.

 

[John Dancy]

Myself and my wife have around 300 DNA matches shown as having "Common Ancestors" - Of these the number that are incorrect can be counted on one hand, however Ancestry seem to be widening their search field and picking up more distant cousins to help our research. This week my wife gained four new CA cousins, all from an incorrect assumption, the trees on each cousin actually showed there was no link, although the families were only living four miles apart.

 

[peter]

Myself and my wife have around 300 DNA matches shown as having "Common Ancestors" - Of these the number that are incorrect can be counted on one hand, however Ancestry seem to be widening their search field and picking up more distant cousins to help our research. This week my wife gained four new CA cousins, all from an incorrect assumption, the trees on each cousin actually showed there was no link, although the families were only living four miles apart.

Presumably Ancestry based the Common Ancestors connection on different trees?

 

[John Dancy]

Yes, quite strange as the 'cousins' trees have branches that go straight past the Ancestry connection. The first(top) name on the cousins list is actually given as "John Grandfather" half 4th great granduncle, born when his 'father' was 55

 

[canadianbeth]

Ancestry has just informed me of a great-niece that Thru-Lines has attached to the wrong sister. She is in my tree as the daughter of S, who is the son of C, my sister. However, in Thru-Lines S is listed as the son of D, my other sister. Neither of my sisters have a presence on Ancestry except in my tree. Can that be fixed?
ETA: I looked at my online tree and S is definitely attached to C, and his daughter is attached to him. How would Ancestry get the relationship wrong?

 

[Stuart]

I now usually see ThuLines/CA displays showing me, then my mother, then me again, then a great-grandparent. I just ignore this, since it's not a bit of the display I'm interested in, and the rest of the line is right. But it does suggest that Ancestry has created a representation of my tree that is uses for these displays and it is wrong.

Since an error has got into this one for my tree, and it's been there for some time, it appears that this representation is created once rather than for each time it's used. Most likely that's done when a new tree is loaded or when it is linked to my DNA test. Sometime soon I will repeat that process and see if the nonsense goes away.

Maybe you are seeing something of that kind. You could try changing the DNA linked tree and than changing it back. Obviously this can produce odd results for a short period, until Ancestry has settled down again.

 

[jorghes]

Ancestry has just informed me of a great-niece that Thru-Lines has attached to the wrong sister. She is in my tree as the daughter of S, who is the son of C, my sister. However, in Thru-Lines S is listed as the son of D, my other sister. Neither of my sisters have a presence on Ancestry except in my tree. Can that be fixed?
ETA: I looked at my online tree and S is definitely attached to C, and his daughter is attached to him. How would Ancestry get the relationship wrong?

ThruLines uses other people's trees to judge where the links are - so I would presume that perhaps someone has a tree (or more than one someone) who links your great-niece to the wrong individual and that is what Ancestry is then showing you.

I've had that before where I have one name for an individual and someone has a slightly different name for the same individual and ThruLines adds them as siblings to the same parent.