Not matching with grandmother

[Phenix]

Hi everyone!

I am new to the site so am trying to work around the technicalities of the website, though I am quite familiar with genetics. My sister had previously tested my maternal grandmother and grandfather, plus my father (including mtDNA and Y as applicable) several years ago. I just recently tested myself and my son and daughter.

The Family Finder results for myself and my children just came in (my mtNDA and Y on my son is still pending), and we all match each other plus my father and maternal grandfather. However, I don't see any match to my maternal grandmother anywhere! I am waiting to see if my sister can give me login access to my grandmother's kit or at least download data to check on GEDmatch, but this seems very odd to me. I could see matching to her and not grandfather due to NPE, but I have never heard of a NME!

From what I have read, there should never be an instance of not matching a grandparent, even with the worst odds of chromosomal inheritance. Has anyone else had this happen? I am assuming it must be a FF problem, but until I get further details with GEDmatch, I can't say much. I do have the FTDNA kit# for her, but it does me no good as I don't have a "match" to her, so on my end it is as if she doesn't exist.

Appreciate any insight!

[prairielad]

Are you sure your Maternal Grandmother had the Family Finder test done and not just mtDNA?

In order to show as a Family Finder match, she would also have to have done done the Family finder test.

Matches could be still updating if both of you have done the Family Finder test....

[Phenix]

The samples for my father, grandmother, and grandfather were all processed several years ago. And you are right, for some reason autosomal was not done on her, but was done on the others!

As my mother and that grandmother (maternal) are both deceased, and I think we don't want to waste grandmother's sample and not run FF now in case some amazing test comes out later, would phasing be of any benefit up two generations? It would be nice to see what autosomal matches we could get to her that could be on her father's side.

[prairielad]

I would phone FTDNA and inquire about your Grandmothers sample and see what is remaining.

Samples degrade over time, so depending on how old it is and how much is left, I would consider doing the Family Finder. The most you have currently of her is 50 percent (what your mother inherited), which would only be about half your Grandmothers 50 percent of her father. (currently on average will only have about 25% of your Great Grandfather)

Currently on Sale for $69USD until May 14th.

[Phenix]

I would phone FTDNA and inquire about your Grandmothers sample and see what is remaining.

Samples degrade over time, so depending on how old it is and how much is left, I would consider doing the Family Finder. The most you have currently of her is 50 percent (what your mother inherited), which would only be about half your Grandmothers 50 percent of her father. (currently on average will only have about 25% of your Great Grandfather)

Currently on Sale for $69USD until May 14th.

Thank you so much for this info, I will look in to what FTDNA says about sample degradation. And I forgot about the Mother's Day sale!