How could a 6th cousin not match?

[LizzieL]

My 6th cousin (and I believe his late father and other relatives) have done extensive research on his (our) family tree. He had the advantage that the surname is unusual and until the 20th century was confined mainly to Yorkshire with some drift to Lancs and Lincs.
Mainly at his suggestion late last year I did an Ancestry DNA test. I now have the results but found we have no match.
However I do have a match with my mother's first cousin. It comes up second on the list of matches showing extremely high probability of 1st or 2nd cousin - which fits well.

This 1C1R gentleman is the son of my grandmother's brother, so my great grandfather is also his grandfather. So it looks that branch of my tree is sound for three generations.

So have my 6C, 1C1R relatives and I made a huge mistake and we're not related or is a 6th cousin too distant to be distinguished definitely?
The weird thing is as soon as I saw a photo of my 6C, I thought he bore a resemblance to another brother of my grandmother's.

[Mart 'n' Al]

Have a look at this chart.

https://dnapainter.com/tools/sharedcmv4

It shows that such a remote relative could have anywhere between 0 and 72 cM for a match.

Martin

[LizzieL]

Thank you
I'm now going through a lot of 4 - 6 cousin matches and they seem to be around mid twenties to low thirties.

One of them has too small a tree (only three generations) and no common surnames but he / she also has a match to my 1C1R (mentioned above) and another 1C1R (but other way round) on same branch of tree. Daughter of my first cousin rather than first cousin of my mother).

[sugarfizzle]

Lizziel.

There are so many situations where you will not be a DNA match with a 6th cousin but will be a goodish match with someone more distantly related.

Standard advice is to test as many of your relatives as possible - siblings, parent, cousins etc., then to try and persuade them all to upload to Gedmatch.

I was hoping to be a match with 5th cousins descended from our mutual 4G grandparents, but no match appeared. No other matches appeared on this line at all - had I made an error with parentage?  Then I found a match with a 6th cousin, descended from previous generation in that line, my cousin is a match with 7th cousin from the same line.

Of course, at ancestry there are the limitations that you cannot see exactly where you match without a chromosome browser.

It may be the case that you need a DNA match at each generation, 'proving' that each child has been assigned the correct parents.

Wikitree provides examples of their standards of assigning DNA evidence.

https://www.wikitree.com/wiki/Help:Triangulation

I assign a DNA icon as main picture in gallery at ancestry, then in pedigree view, looking to see where an icon is missing, then perhaps use the surname or place search to see if I can find any appropriate matches.

Most of my 2G grandparents now have an icon attached.

DNA is an additional tool, doesn't replace paper trail. Go with your paper trail, until and unless you find evidence to the contrary - absence of DNA matching, especially at this distance, is not evidence.

Regards Margaret

[medpat]

We all get varying amounts of DNA from each of our parents, multiply it by several generations and some people may have very little of one particular family's DNA.

I have a brother and sister whose gt gt grandfather is the brother of my gt  gt grandfather, we meet at our 3rd gt grandparents so are 4th cousins.

They both link to me and some others from this line but on occasion with a more distant relationship only one of them has linked to others.

[LizzieL]

Thank you all for your replies, it makes me feel more confident.
How do I upload results to GEDmatch?

[sugarfizzle]

This link tells you how to upload to other sites -

http://thednageek.com/how-to-transfer-your-ancestrydna-test-to-other-databases/

Regards Margaret

[Mart 'n' Al]

Somebody should compile all these useful tips, hints and advice into a single document. Perhaps I'll do it myself when I've found my three remaining great great grandparents.

Martin

[LizzieL]

This link tells you how to upload to other sites -

http://thednageek.com/how-to-transfer-your-ancestrydna-test-to-other-databases/

Regards Margaret

thanks, just uploaded to GEDmatch