Ancestors are related, how does it affect Family Finder?

[Biblioteque]

keigh: Interestingly, last week I looked at the tree of one of my matches at (Bleep), and she and I had a MRCA, and that ancestral couple was in her tree 8 times!!! The paper trail on each of our sides was rather deficit, but it was interesting.

[keigh]

keigh: Many of us are finding some of our MRCAs in Colonial America. Of course, these matches have to be proven with segment matching.

Yes, many people have MCRAs in Colonial America and many of those ancestors have intermarried. Having a segment matches linked to a good paper trail is one way to confirm those ancestors.

What I was trying to say was that having many cases of intermarriage among your ancestors can add to the confusion as to just how closely those MRCA's are showing up in the cousin matches.

[Biblioteque]

keigh: Many of us are finding some of our MRCAs in Colonial America. Of course, these matches have to be proven with segment matching.

[keigh]

If there is intermarriage then the dna can show up as a closer match. I have a great aunt who married one of my 1st cousins 3X's removed. Their children are more closely linked to me than their father is. My father's grandparent's were 3rd cousins, a set of GGGG grandparent's were 1st cousins, two of my 6th Great grandmother's were sisters, etc. and so on.

Figuring out possible descendent line is a scramble. Example a cousin who is descended from one of my 2great grand aunts, might also be showing the dna from the husband of the 2nd great grand aunt since his mother shared the same maiden name as her daughter in law.

Between my brother's test and mine we have over 1400 cousins, of which only just under 400 match both tests. However we do seem to have a large number of 2nd to 4th cousins showing. I'm looking farther back for actual ancestors for the matches.

[1798]

Your results will depend on how you inherited dna from these inter-related ancestors. It will certainly be possible for you to appear more closely related to some of your matches than you truly are! Please let us know how it turns out?

If my ancestors married their cousins then they would be closer related to me than others.

[MerryB]

Your results will depend on how you inherited dna from these inter-related ancestors. It will certainly be possible for you to appear more closely related to some of your matches than you truly are! Please let us know how it turns out?

[JohnG]

You may match many people because of those marriages of related people in a specific location. My wife's grandmother came from a county like that. If her matches mention that county, we can find at least one connection and maybe several. The odd thing is my wife once moved there for work and felt very at home, long before we learned that perhaps the friendly folks were all 6th cousins by three routes.

[jonr]

I'm still awaiting results, meanwhile, I'm curious on how related ancestors affect results on the Family Finder test.

In my case, my grandfather's parents were half 1st cousins. Also, my grandfather's father's parents were 1st cousins. There are more complications, I could keep on telling for a while... What can I say, many of them come from a small place. ;-) If you go back five generations before my grandfather you would expect 32 different persons, in this case, some of them are "duplicates" and only 20 different persons can be found at this level. To be precise, one couple is repeated 5 times and two other couples are repeated 2 times.

I suspect FTDNA to exaggerate matches from this branch of my family tree, that is, maybe a 4th cousine will be predicted as a 2nd cousine etc. Is this a correct assumption? Could there be any other unexpected results?