This is good advice, and I will try the GEDmatch. I cannot do Y chromosome analysis, as I do not have a Y chromosome. I am avoiding disclosing surname here, but it is an Italian surname and the entire crew of greatgrandparents and great(2) grandparents on that side are from San Mango Sul Calore, Italy. My grandmother on that side was adopted, so although her parents were also from this area, they don’t “count” in the genetic question.
The term I heard was “pedigree error”. There’s the apocryphal story of the teacher in a lower class London area doing a class on blood types, asking each student to check their blood types with their parents to demonstrate genetics- only to find that 25% of children suffered from pedigree error. (1) BS, how many lower class British from the 1970s or earlier knew their blood type? (2) Even there number seems way too high (3) probably just slander, put-down of the lower class - demonstrate their moral turpitude, and (4) since the more common blood types are very common and recessive usually, the odds that even if 25% were bastards, that 25% would fail a blood match is unlikely - it would probably suggest an error at the level of 40% or more. And (5) I’ve searched for the original source and never found any reference. It’s urban legend material.
IIRC I read something about that 10% study which included a lot of adoptees and remarriages, basically 10% of children were not the offspring of both adults in the current household - which is quite plausible in almost any town in the western world given today’s divorce statistics. It didn’t mean hidden parentage.
But reading between the lines, it seems like mama had a fling (most likely explanation) either for purpose of expanding the family (if the famial resemblance is not too bad) or for other reasons (if the OP is distinctly different.) The first thing to do would be to find where mama worked or who the close family friends were around that time, if you can. …of half-English heritage.
There’s even an ad on TV for I think Ancestry where the person says “I though our family was Italian, turns out we’re eastern European…” Family migrated to Italy a generation or two earlier.
IIRC too, when they tested slave and free descendants of Thomas Jefferson (or alleged) some were, some weren’t the same family tree… Suggesting some pedigree errors in the intervening years. Plus, it could have been his father or uncle…
The OP might find this article interesting.
I wouldn’t bother retesting with My Heritage - I’ve seen lots of posts calling their accuracy into doubt. Specifically, I’ve seen other genealogists calling them out for predicting relationships between tested individuals to be falsely close, where the other sites have all correctly predicted relationships to be more distant. Their ethnicity predictions have also been mentioned to be harder to align with documented ancestry than the other sites.
The straight up, simple route is to have a documented relative from your paternal family test, and to contact people with trees containing your paternal ancestors to establish if there’s a documented connection, and if there is then find out if they have tested.
Your close family seem to be out of the question, but a more distant relative is less likely to be caught up in whatever unpleasantness has been going on. If you can find a second or third cousin, that would do the trick. Fourth cousins will not match you 50% of the time so not matching a single fourth cousin would be inconclusive.
Keep in mind that your documented family tree only goes back so far; the ethinicty estimates go back further. Almost no one living in Ireland, for example, with documented Irish ancestry back hundreds of years would come up as 100% Irish.
You’re a trans man? You mentioned family transphobia earlier; I can totally relate.
Deep in the heart of Campania—you’re of Samnite origins. I’m a Messinese trans woman and I love studying Italian history and prehistory. I just got done reading Elena Ferrante’s Neapolitan novels (My Brilliant Friend etc.), about people from your region. My family gave me grief too.
Not necessarily. Although exactly* half of your DNA comes from your father, it is not true that that half must be precisely divided between his parents. It is, in theory, possible for you to have anything between 0% and 50% from any particular grandparent. In practice, the odds are very very good that the true number will be close to 25%, but it’s random selection.
As a professional geneticist, I would not take anything from these tests beyond perhaps motivation to get proper forensic work done if you’re really interested. It’s not that there’s anything wrong with the tests themselves - they’re all done at LabCorp, and they’re competent - it’s just that the links between certain markers and certain populations are never rock solid. They’re all based on probability and don’t always reflect exactly what we think they do. I would be really really cautious drawing any conclusions or taking any action based on these reports alone.
If nothing else, there’s always the chance that a traveling salesman came through town a hundred years ago and left some strange DNA behind him.
I would take the Country origins portion with an enormous, heaping grain of salt. The portion you should look at to determine paternity/non-paternity is the DNA relatives section only. You can and should test at all 3 of the major sites, which are Ancestry.com (which you did), 23andme.com, and Family Tree DNA. MyHeritage uses the same chip as one of the three major ones and their DNA matching seems suspect so I wouldn’t use them at all. Get as many relatives as you can to test, and as close a relative as possible. Particularly important if possible are parents, aunt and uncles, and grandparents as those help you filter out relatives by which “side” of the family they are on.
yes, notice those are “unpublished” especially the 20% to 30% is sort of peripherally mentioned in another discussion.
Note the preliminary remarks -
I still don’t buy it. Blood distribution for the UK is:
O+ 37.0% A+ 35.0% B+ 8.0% AB+ 3.0%
O- 7.0% A- 7.0% B- 2.0% AB- 1.0%
The wrong father would need to be of a blood type that contradicts what the expected father is; i.e. AB makes it easy to determine the paternity, but that’s 4% of the population. The only possible fairly common combination would be an couple that is both O and a hidden father not O. A and B could both have O recessive and 50% chance of having an O child. It would be a fun exercise to consider the odds, picking at random, of discovering a paternity error for every threesome combination of blood types.
For example, and O and A have a child - which combinations are impossible?
B and AB, so 14% of the possible blood types. The child could be A or O, also + or - and unless both parents are - and the child is + there is no contradiction. Ditto for O and B; any parent and AB, only O is impossible. etc.
This is why I think the story is BS - to get a 30% “definitely wrong” parentage, you’d need a FAR higher actual parentage error. I don’t think any social class has that level of soap opera going on.
Well (playing devil’s advocate here) they could have been looking at more than just ABO.
Mazel tov!
I guess the next question would be how routine and how expensive would that level of test be in the 1950’s and 1960’s?
IIRC a common issue in those days in paternity tests was whether the alleged father could possibly be the father - but more often than not it did not rule out the father; even with AB involved, it was still possible that someone else was the father.
then you’re back to the dominant-recessive issue. A dominant gene could be paired with a recessive one; so an A, B, or O mother paired with an A,B, or O father could produce an O, or whatever one of the parents is, A or B. Only an AB father (or mother) cannot produce an O child. Presumably the same applies for many of those other characteristics in the linked article. Without DNA, all you can do is narrow down the odds unless there’s a direct contradiction of dominant characteristics. In the days before DNA tests, it was not simple to determine what recessives were carried except maybe an in-depth family tree study. Which of course brings us back to the premise of the studies…
ABO and Rh are pretty common tests because it is necessary to know for hospitalization or blood donation; what are the odds an “unpublished study” would be able to afford hundreds of more in depth tests?
You usually can’t conclusively say that any given case is a nonpaternity event, just from blood types. But you should be able to calculate the overall nonpaternity rate from the degree of correlation. A father with type A blood won’t always have a child that’s A or AB, but he should have A or AB children more often than the population average. And you can calculate exactly how much more than average, if you know the relative frequencies of all of the types. If, then, you find that it’s less than that, then you can attribute that to a certain percentage of nonpaternity.
EDIT:
Likewise, an O parent cannot produce an AB child. And a pair of Os can have only an O child, and a pair of As or an A and an O can’t have a B (and vice-versa).
Here’s a chart on paternity and blood types:
The chart shows that there’s a lot that can’t be proven–for example, if one parent is type A and the other is type B, their children could be any of the 4 types, including O.
Like my parents
Like my 8 siblings and I. We got almost every combo.