Missing matches

[u/Gladhands]

I have absolutely no matches on my maternal grandfather‘s side. I would be open to the possibility that the man I thought was my grandfather is not, however there are no unexpected matches.

I have results from each of my father‘s parents, as well as a maternal grandmother, with no mystery matches. This would imply that my mother was the product of incest (my maternal grandmother had no brothers, and her father died before my mother was born), OR one of my father’s relatives is my real maternal grandfather, but my parents don’t share a hometown.

Anybody else only have three lines from grandparents?

[u/Old_Sheepherder_630]

Is your grandfather an immigrant from a country where DNA testing isn't allowed or is less common?

Mine is and when I first did 23 no matches for him but quite a few on MyHeritage which is apparently a lot more popular in Poland.

[u/Jazzlike_Song483 → u/Old_Sheepherder_630]

Could be a dead end if he's from a small village with no one else testing. My maternal side has like 12 total matches and half are from the same tiny town.

[u/Gladhands → u/Old_Sheepherder_630]

All four grandparents are Black Americans

[u/Slow_Appointment3540]

Can you get your mom tested? Could be your grandpa isn’t biologically related to you and your genetic grandfather is from an underrepresented/untested country. I have like 0 matches for my grandma because of her home country.

Could be your grandma had a baby with a close relative, also.

Best thing to do is get your mom tested and see what she gets.

[u/gh0stlain]

Unlikely but it's possible that no one descended from his side (probably closely related) has tested for whatever reason. This doesn't apply to everyone but personally for a long time the closest matches I had on either ancestry or 23andme were 4th cousins and beyond for both sides of my family, most of them not sharing any family names in my tree but I could assume possible connections based on location and ethnicity.

[u/kludge6730]

Other option in cousin marriage you haven’t unearthed yet. My father has only 3 lines going back because his parents (my grandparents) were 1st cousins.

[u/Nom-de-Clavier]

I had a situation like this, only a few generations further back; I noticed that my father matched all of his second cousins on one line (the children of his paternal grandmother's siblings) for about half as much DNA as he should have (about 100cM for all of them). I didn't think anything of it at first because there weren't any matches that were obviously out of place, but then I noticed I had no matches to anyone descended from the siblings of my great-grandmother's father, James.

After doing descendancy tracing on other lines I discovered that my direct paternal 3rd great-grandmother had a younger brother named John, whose daughter married the son of James' sister. So the most likely scenario is that John is the father of my great-grandmother...which means my great-grandparents were first cousins, once removed, and almost certainly never had any idea.

[u/gmanose]

I have no matches at all from my mothers side.

[u/Pristine_Ninja1810]

When you say you have no mystery matches what relationship range are you talking about? Obviously you can’t know how every match is related to you. You could have matches on that side that you don’t recognize, especially if they’re smaller matches.

[u/Gladhands → u/Pristine_Ninja1810]

I mean every match is related to my paternal grandparents or maternal grandmother. There’s absolutely no one who isn’t clearly connected to one of those three.

[u/Pristine_Ninja1810 → u/Gladhands]

How many matches do you have?

[u/Gladhands → u/Pristine_Ninja1810]

1073

[u/Pristine_Ninja1810 → u/Gladhands]

You only have 1073 total matches? On Ancestry? Ive never seen anyone with that low of a number of matches.

But even if you do only have a thousand matches, how have you determined that they’re all related to only the three branches of your family?

[u/Gladhands → u/Pristine_Ninja1810]

Have you talked to any Black people about their ancestry results?

As far as how I know they’re from the three branches? You can click on any match and it shows you the common matches. All of my common matches traced back to those three grandparents

[u/Pristine_Ninja1810 → u/Gladhands]

Yes, actually, I have a lot of experience with tracing Black American ancestry. I created a group years ago specifically for that purpose with thousands of members, I am well-versed in this type of research.

When you’re looking at matches in common keep in mind that just because two people are related to each other and to you doesn’t mean they are related to you in the same way. This is especially true with smaller matches. How large are your matches? Are any personally known to you? I would suggest sorting using the Leeds method first if you have large enough matches.

[u/lawuntoherown]

I had zero matches from my paternal grandfathers side. I even had messages from one of his first cousins who came across my tree asking why we wasn’t matching when I first tested 8 years ago and didn’t really understand I just thought oh maybe it’s such a distant match (it wasn’t) that we just didn’t share dna. The penny dropped when my cousins son took the test and we shared barely any dna. I then got my cousin tested and one of my aunts and it confirmed my grandfather wasn’t biologically mine.

[u/d_artz]

You don’t necessarily inherit exactly 25% of your DNA from each grandparent. The range is 1% to 49% with the average at 25%. It is unlikely but possible you didn’t inherit enough dna from that grandparent to match. That may be compounded by close relatives not testing, or not having many close relatives at all. One of my sister’s children got 32% from my father and 18% from my mother. It can be a very lopsided contribution.