DNA Query

[Mitche11]

I have a DNA match on my heritage, I know he is related to my paternal side but after making contact with him he is trying to find his father. I match with him as probable 3rd cousin and we share 3 matches but this is where i am really confused.

We both match with Mrs A: Mrs A is my 3rd cousin which is correct but Mrs A to the other match is a probable parents 3rd cousin, 3rd Cousin, then we both match to Mr B: Mr B is my 4th cousin which is correct but to the other match is a probable parents 2nd cousin, 3rd cousin, then we both match to Mr B's daughter: Mr B's daughter is my 4th Cousins daughter which is correct but to the other match is a probable 3rd Cousin.

My question is am I correct in saying that if a parent is your parent's 2nd cousin then their child will be your 3rd cousin? If this is correct then how can a parent and their child both be your 3rd cousin?

I hope I have made some sense to the above and any help would be very much appreciated!

[Purpeller]

These are just estimated relationships. You need to work on trees and make your own judgement.

[Mitche11]

These are just estimated relationships. You need to work on trees and make your own judgement.

I do understand that and that is what I have done but there is something not right somewhere with the shared matches. I have worked out a lot of my matches and they have worked out correct for the probabilities My Heritage listed but for the person I’m helping and shares matches with me the probabilities of their matches are really strange.

[Biggles50]

I have a DNA match on my heritage, I know he is related to my paternal side but after making contact with him he is trying to find his father. I match with him as probable 3rd cousin and we share 3 matches but this is where i am really confused.

We both match with Mrs A: Mrs A is my 3rd cousin which is correct but Mrs A to the other match is a probable parents 3rd cousin, 3rd Cousin, then we both match to Mr B: Mr B is my 4th cousin which is correct but to the other match is a probable parents 2nd cousin, 3rd cousin, then we both match to Mr B's daughter: Mr B's daughter is my 4th Cousins daughter which is correct but to the other match is a probable 3rd Cousin.

My question is am I correct in saying that if a parent is your parent's 2nd cousin then their child will be your 3rd cousin?

If this is correct then how can a parent and their child both be your 3rd cousin?

I hope I have made some sense to the above and any help would be very much appreciated!

Yes you are correct with your first query.

The child of your 3rd Cousin is your 3rd Cousin Once Removed.

As already advised.  The predicted relationships are just that predicted, you would need to build a tree between you and them to more easily visualise the actual relationships.

I find Post It notes invaluable for visualising relationship with DNA matches

DNA inheritance is a random process which makes its presence felt more beyond Grandparents.  There result is that there is a degree or variance in the relationship predictions that may not make sense.

Additionally if say a child of a DNA match shares more cM than their parent does then their other parent may have contributed to the matching DNA segments.  I have a Father on 18cM and his son on 42cM, they are still a WIP as they are only on Ancestry.

[tatt1994]

Provide them with as much information as you can on your family tree. I find it much easier to work on ancestry and you could encourage your relative to test and set up a tree there, if they have not already done so.

[Glen in Tinsel Kni]

I find the MH relationship predictions to be all over the place. I have a maternal 1c, 1c1r and 1c2r (all descendants of one of my uncles), the predicted relationships  are 2c, 1c and 1c respectively.  Yep, the closest of all with the highest dna share is predicted as the most distant of the three.

[rsel]

Adding to what the others have already said :-)  MyHeritage does also show other options it has calculated for the relationship, you can either see them by clicking on the relationship label in the matchlist or looking in the specific section on the matches page.  However i personally prefer to enter the cM size into DNAPainter to get its view on the relationships, as it gives more options and i find the MyHeritage 'terms' a bit odd (i.e giving relationships to you parents rather than you in some cases)

Richard

[Glen in Tinsel Kni]

I find the MyHeritage 'terms' a bit odd (i.e giving relationships to you parents rather than you in some cases)

Richard

The general opinion being that many people would have no idea what a 'removed' cousin is but understand parent's cousin. I too find it confusing describing my relationship to someone through a third party.  The default setting/assumption of a full relationship is also a huge drawback to those of us who primarily have half relatives, it's just another step in the initial check of any match having to manually select the half relative options whereas Ancestry throw them up just by clicking the shared cM value.
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