No announcement yet.

Advice needed - DNA and parentage question

  • Filter
  • Time
  • Show
Clear All
new posts

  • Advice needed - DNA and parentage question

    I have a general enquiry I’d really appreciate some input on. It is sensitive and impacts people still living so I need to keep it anonymous – I am a member on other genealogy forums but my identification and that of those involved could be too easy there, and this seems the most knowledgeable one in understanding the science of it all (I'm still fairly new to all this) which is why I’m here.

    It’s a straightforward question really about DNA, and my maternal lineage.

    I know ethnicity is an imprecise science at best, but I need to start there to lay out the issue and seek some objective opinions.

    Firstly, my ancestry has been researched by several family members (including myself) and apart from one uncertain line on all others is traced to at least the 1700s. DNA matching has happily confirmed a lot of these lines.

    My mother’s DNA returned a huge amount (consistently around 60%) of Scandinavian with no known origin. It also showed DNA hits to 2nd/3rd cousins in a Scandinavian country with no family tree connection. In speaking to these newly discovered relatives multiple males from their family have historically migrated via the UK (and possibly stayed) mainly to the US.

    Now, I know ethnicities are variable estimates, and I view them as more colour blocks of specific DNA that are given certain ethnicity probabilities, but all the same, there’s this block of unexplained DNA. Two 1st cousins of hers have tested, one each from what should be her paternal and her maternal side, which show 0% and 5% Scandinavian respectively (and are given as 1st cousins once removed and 2nd cousin instead of 1st) so it’s not showing on either side. To rule out her recorded father being illegitimate she has a 3rd cousin match to a direct descendent of his correct grandfather.

    Myself and a sibling show around 25-30% Scandinavian, confirming this block of DNA is there, and these results have be duplicated across several companies including Ancestry and confirmed with Gedmatch for both of us. We do not get it from my paternal lineage – that’s rural England with cousins on that side who have tested and show close to 100% “GB DNA” and no Scandinavian.

    There’s DNA match clusters in the US in particular with no known connection but again high levels of Scandinavian and a couple with 20th century migration in their trees from the same country these European 2nd/3rd cousins are from. There is one surname that’s come up several times in different trees. There’s also an international scattering of Germanic/Baltic 3rd/4th cousin hits with no known connection. Unfortunately there’s no closer relationships showing at the moment, and many of the more distant ones have no trees to check for more information.

    Gedmatch Oracle shows the closest population matches for us as Orcadian, Danish, North Dutch, Swedish, Irish, West Scottish and Norwegian. No known reason for any of these except some Irish. I have no idea how useful the archaic DNA is but there are high levels of Eastern HG with archaic East Asian/Meso American and some Denisovan DNA all as I understand suggestive of Baltic, Scandinavian or Eastern Eurasian ancestry.

    To give some social context to her birth, her registered parents were not young at all when she was born with a large gap after the next youngest child, and single older daughters of childbearing age. It was also during WW2. She is recorded as their child, but her birth, registration and baptism all happened well away from their home town. One of the sisters and her “mother” were away for several months. Among the younger generation in the family this question has been speculated about in the past, long before any DNA testing.

    Just looking at the science and DNA mainly, but also with reference to experience of genealogy, is there any other reasonable explanation other than she was actually the daughter of one of her unmarried sisters and a (probably American?) man of recent Scandinavian descent, who was raised by her grandparents? How hard was it to give false details in a birth registration at this time (WW2 UK)? Is it possible for such a large percentage of her DNA to be so different from the rest of the family, and only present in her and her children? Is there any other explanation?

    As far as I know she has never suspected her parentage so I need to proceed with the greatest caution, but she is the one who has been pushing the research from the beginning and paying for family tests, and encouraging more. She’s an intelligent woman but I’m managing the online kits as she does not generally use the internet, and I’m finding it harder to fudge the implications of what I’m seeing.

    Any and all suggestions and advice would be gratefully received

  • #2
    Yes, this is sensitive. Possible, but not proven.
    If you wish extra privacy, you can also send me a private message.

    1. Ethnic % alone is unreliable

    At first, I ignored the ethnic % as unreliable. It is common to show neighbouring regions of Europe, because our dna is similar and mixed during history. But ...

    2. DNA matches show you may be right

    Your mother is related to all the known relatives, yet somewhat more distant than she is supposed to be:

    known ... estimated by dna matching
    1C ... 1C1R
    1C ... 2C
    descendant of his correct grandfather (2c or 2c1R??) ... 3C

    You can check the possibile relationships with these tools:

    Randomly low matching or impossibly low?
    There are 2C-3C unknown matches of Scandinavian origin.
    Do they have big trees, or can you help those people to discover more?
    It proves nothing yet, but yes, it raises suspicion.

    3. Circumstances of birth are suspicious

    Long absence, born away from home, wartime ...
    It makes your scenario likely.

    "Among the younger generation in the family this question has been speculated about in the past, long before any DNA testing."

    When doubts are present, there is statistically greater chance for a NPE than in a quiet situation.

    4. DNA options:

    Are there any mother's sisters/brothers still alive and willing to test? If your mother is in fact their niece, they would

    - share less dna than expected for siblings
    - if compared on, full siblings show matching on both sides (sharing material from both parents); a niece matches uncles/aunts on one side only.

    If the sister/suspected mother is alive, she would probably
    -decline testing (and raise more doubts)
    -confess the truth
    -agree to testing (and show as sister).
    Would you ask her or maybe not?

    When simple solutions are unavailable, working with segments of dna may be helpful.


    You deserve the truth about your roots, and you want your family to be ok. I really really wish you good luck.


    • #3
      Elliemario and Emona - there's also a new tool at dnapainter, which could be very helpful in this situation. See