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General => Ancestral Family Tree DNA Testing => Topic started by: shoshannah on Sunday 23 May 21 07:48 BST (UK)
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Hi all,
Im a little confused about dna results.
A friend has had her ancestry dna report back. It shows:
72% Scotland
28% England
The confusing thing is that only her mother was Scottish and had Scottish ancestors. Her fathers family was entirely English. Going back, Her maternal grandmothers line is Scottish but all other grandparents and family lines are English. There are no other Scottish ancestors other than in her mothers mothers line. Why would her % Scottish DNA be so high?
Many thank,
Shosh
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This is one of many many articles on the subject:
https://www.wired.com/story/your-ethnicity-estimate-doesnt-mean-what-you-think-it-does/
It’s one of the first I came across via a Google search and aimed at the American market but may help give your friend an explanation.
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To summarise the article above, and Ancestry's own information, the fact that you have an ethnicity estimate showing 72% Scotland, doesn't mean you, or your Ancestors are or were Scottish. All it means is that you share a large part of your DNA with people whose family are known to have lived in Scotland for a large number of generations.
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This is one of many many articles on the subject:
https://www.wired.com/story/your-ethnicity-estimate-doesnt-mean-what-you-think-it-does/
It’s one of the first I came across via a Google search and aimed at the American market but may help give your friend an explanation.
That's a good explanation. I've bookmarked it. Increase in Scottish DNA is mentioned in first paragraph.
Author points out later in article that ethnicity results of siblings may differ.
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Thank you for your advice...unfortunately I still don’t understand.
Family research shows that this one line lived in Scotland. All the others lived in London or southern England. This goes back to about 1700s. Does this mean that prior to this, a large proportion of my friends ancestors were from Scotland?
Thanks again, sorry I’m not getting it!
Shosh
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The short answer to your question is "No" or at least "Not Necessarily."
The medium length answer is that what these results show is that the tester's dna matches people who Ancestry class as "Scottish." Ancestry consider their comparison group as Scottish based on their genealogy placing them (and their ancestors) in Scotland for several generations.
The long answer is that Ancestry (and every other genealogical DNA testing company) simply try to match your DNA sample with other people who have "known" association with a particular location.
Contrary to popular belief, there is no such thing as Scots, Irish, Norse or anything else DNA.
What there are, and what DNA testing companies rely on, are similar clusters of DNA segments (called SNPs) which are common in populations around the world. Where a particular SNP is identified with a particular location (because it appears in the DNA of a relatively high number of people whose genealogy is associated with that location over several generations) then it serves as a marker that your ancestors MAY have lived in that location at some stage. The more SNPs associated with a particular region, the higher the %age it produces in it's final estimate.
The thing to remember is that Scotland and England have both been subject to major migrations, invasions, and simple movement of people in search of work etc.
To give an example My own family are pretty much constantly from the mining villages of Lanarkshire and West Lothian on my mother's side, and farmers in Ayrshire and Argyll on my father's right back to the late 1600s. One couple came across from Ireland - my first brick wall, sadly - but otherwise it's all Scottish - which in my case matches the ethnicity estimate surprisingly well. However, given that both sides of my family lived near the coasts, it seems highly unlikely that no where in my line is there someone who married someone of Norse descent - but that doesn't show as "Norse" dna, because it's probably true of almost everyone in Scotland.
The other point to remember is that estimates of ethnicity based on current dna are less science and more guesswork with a bit of probability thrown in.
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These estimates aren't set in stone either. My mother's has updated several times since she took her test, with some countries getting a bigger percentage and some disappearing completely. As far as I'm concerned the nationality estimates are practically useless.
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It can be tricky to get your head around. Albufera32’s explanation is very concise, so I hope that helps.
I think the simplest thing to tell your friend is to simply ignore the ethnicity results. They are only a very rough guide, nothing more, and those percentages will change over time.
The reference populations that Albufera32 talks about consisted of people who could claimed that they could trace their paper trail back a couple of generations within the same geographical location. Si these people knew that, for example, that all of their parents, grandparents and great grandparents were all born within that specific area. Before that, in theory, those ancestors could have come from anywhere in the world.
Think how many millions/billions of similar small regions there must be in the world. Think how few people can be 100% certain that their paper trail is accurate, as there can be errors in official documents too.
Also consider that a lot of areas in the world may not yet have collected sample populations who can prove their lineage back x generations, and many remote areas may never have had official documentation of births.
Take into account the odd unrecorded NPE, and it is easy to see how and why ethnicity results are a bit of a mishmash and not to be relied upon.
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Ok, I think I understand. The ancestry ethnicity % is saying that my friends dna has elements that are similar to those people they have tested whose ancestry are claimed to have come from Scotland, though they may be incorrect or they may be from somewhere else but just known to have lived in Scotland. As the pool of testing increases and it become more accurate and less guesswork, then these % may change.
Do I understand?!
Thank you!
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If she has DNA matches with paternal cousins, it'd be interesting to see their Scottish % .
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Ethnicity estimates are just that - guesstimates!
They shouldn't be relied upon.
More to do with marketing than science.
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Thank you for your advice...unfortunately I still don’t understand.
Family research shows that this one line lived in Scotland. All the others lived in London or southern England. This goes back to about 1700s. Does this mean that prior to this, a large proportion of my friends ancestors were from Scotland?
Thanks again, sorry I’m not getting it!
Shosh
X Duplicate post. Sorry
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Yes to estimates / a guide. Also anyone of your line(s) can have another biological father - non-paternity event (NPE). That changes things. We're getting into 32, 64, 128...
Can you honestly account for a high % of your DNA matches? I can't and done extensive work on mine. There are NPE at various points and would hazard this would occur for everyone at some stage in their own trees.
In my research I have viewed very large detailed trees that people have worked on for years. At a paperwork level they are fine but at a DNA match level I know areas are wrong.
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Ok, I think I understand. The ancestry ethnicity % is saying that my friends dna has elements that are similar to those people they have tested whose ancestry are claimed to have come from Scotland, though they may be incorrect or they may be from somewhere else but just known to have lived in Scotland. As the pool of testing increases and it become more accurate and less guesswork, then these % may change.
Do I understand?!
Thank you!
Yes. ;D
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I gave up on ethnicity when they told me that both my son and I have 16% Scottish. I have not found any Scots in my research for my line, but my sons grandmothers line goes back five generations born in Scotland.
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I find the ethnicity very useful and often turns out to be truer than at first glance
If the parent had family from north england they would probably have scottish blood from way back in history in several lines .
Im over 50 percent Scottish most from my father but we found that my mothers great great grandmother was also Scottish.
Its a good idea to look at shared matches and see how Scottish they are + how many of the great grandparents you can identify shared matches in case there was unknown adoptions or illigitimacy in one line