DNA cMs

[Lanc81]

Apologies if this questions been asked before...
I have a match that's 335 cMs, from research they are more likely a half second cousin than a full cousin. They have a well researched tree and it looks like there actually related to both my parents one closer the other more distant. Just wondering if this makes the relationship look more closer than it is. Hope that makes sense 

[Gadget]

I have a 3rd cousin match at 296cM. When I  investigated, he's a straight 3rd cousin but we also share a more distant ancestor.  This double relationship happens most often in small villages. I have a number of similar, but more distant, matches.

It means carefully constructing the match's wider tree.

Gadget

[Lanc81]

 Thank you for the reply that's interesting. They share a half first cousin on my mothers side and there looks to be a few distant connections on my father's side.   

[Biggles50]

Where you have relationships as you describe, this is known as Endogamy and typically happened in rural communities where the gene pool was limited.

Your 335 cM could resolve at 3xGGP level or closer if Endogamy occurred.

I appear to have this occur with one of my DNA matches, she is 364 cM to me but two of her first Cousins are both around 100 cM to me.

I have in my own tree distant Cousins marrying each other and also in my Wife’s where we can trace her lineage directly back via different branches to three of her xGGF’s who were full Brothers to each other.

So DNA can lead to confused results in the options presented by DNA Painter and Gedmatch.

[Gadget]

So you agree with me, Biggles 

Endogamy just means marriage or inbreeding within a group - local, clan, tribe ..

[Lanc81]

  thank you both. That's confirmed what I thought might be the case.

[Biggles50]

So you agree with me, Biggles 

Endogamy just means marriage or inbreeding within a group - local, clan, tribe ..

Totally