How far back can AncestryDNA's "Common Ancestors" feature work?

[LizzieL]

I just "lost" a Common Ancestor match yesterday. He was originally shown as my 5th cousin once removed. His 5th gg-mother being shown as sister of my 4th gg-mother, so the shared ancestor were my 5th ggparents and his 6th ggparents.
However his 5th gg-mother was actually the niece of my 4th gg-mother, (there being a 19 year difference in age between my 4th gg-mother and her oldest brother). So the shared ancestor was still my 5thh gg-parents but now his 7th. As Ancestry only goes back to 6th gg-parents, he dropped off my common ancestor match list. Don't know what has happened to all the other tree clones which erroneously show the two ladies as sisters and not correctly as aunt and niece. I counted up to 20 then gave up. Clearly the "sister" was a remarkable lady giving birth to three children after her death!

[brigidmac]

I dont understand replies 11 +12

Why is it horrifying to have 3 Different thru line links to same   person
&

Why cant you add two and more colour codes to the same person

Or have i misinterpreted ?

[History Lives]

Why cant you add two and more colour codes to the same person

You can, but what I mean is normally I would look at the Shared Matches between me and a match with a known relationship, i.e. I know we have the same 2x great grandparents or something, and I would colour all of those shared matches with the same colour code. You can't do that in a community with high levels of consanguinity (inbreeding) because you can't assume they are related along that line, because they could be related along a different line, or both, and you have no way of assuming this unless you know for sure and both of you have detailed trees, then you could colour code and add multiple colours if necessary.

[brigidmac]

Thanks history lives
That makes sense i have that problem on the side of a jewish great grandfather i think its called endogamy when related families inter marry

[Redroger]

Yet is is clearly possible to get back over 500 years or more. If it wasn't then the allegedly DNA tested skeleton of Richard 111 could well be a fraud, and attempts to isolate Royal remains at Winchester from the bones jumbled by Cromwell in the 17th century likewise.
Anyone enlighten me please?

[History Lives]

Yet is is clearly possible to get back over 500 years or more. If it wasn't then the allegedly DNA tested skeleton of Richard 111 could well be a fraud, and attempts to isolate Royal remains at Winchester from the bones jumbled by Cromwell in the 17th century likewise.
Anyone enlighten me please?

The Richard III false paternity issue was from looking at YDNA, which passes from father to son along the Y chromosome, and not using autosomal testing, which is your bread and butter genealogy test.

[davidft]

Yet is is clearly possible to get back over 500 years or more. If it wasn't then the allegedly DNA tested skeleton of Richard 111 could well be a fraud, and attempts to isolate Royal remains at Winchester from the bones jumbled by Cromwell in the 17th century likewise.
Anyone enlighten me please?

Wasn't it a case that the test done for Richard III's descendants was much more specific for example it was only tracing the female line, and then an anomaly on that line and other facts like that. Yes we could all have tests done like that but they would cost a lot more and you would be ruling out 99%+ of people straight off by taking such a test.

In short they are highly specialised tests for specific questions to be confirmed or refuted.

(Well that's my understanding of it)

[Albufera32]

I dont understand replies 11 +12

Why is it horrifying to have 3 Different thru line links to same   person
&

Why cant you add two and more colour codes to the same person

Or have i misinterpreted ?

The "horrifying" was a joke.

My maternal line were miners. There appears to be a very, very high level of families inter marrying within a relatively small group. (To give one example, I have one case where of six children that a couple had, 5 of them married their first cousin.) I assume this is related to the "serf" status of miners up until 1799, although it seems to have carried over well into the 19th and even early 20th century.

[brigidmac]

Yes Richard 3rd was tested thru a maternal connection male descendants were all eliminated as would have been threat to the throne .
I went to a couple of talks by the leader of the dna team
It involved taking tiny bits of his teeth to specialists in other countries .

Maybe bone DNA is more stable than spit & swabs but less accessible for general public to extract
.i.ll raise the question next time !

As far as ancestry is concerned before the 8cm cut of limitation I had a thru line to a match of 6cm ...think it was linked to 4x ggparents