To think these DNA ancestry tests make no sense

[CarolineFields]

So you get back a score of 40% Nigerian. Meaning out of the tiny scrap of DNA tested - less than 0.1% -40% of that matches the average population in Nigeria. But if those Nigerians are tested, they won't come back as 100% Nigerian, so 40% of 0.1% matches people who are likely to be told they are 50% not Nigerian?

And if you are in Iceland when you have that test, you are told you are 40% Nigerian, but someone in Australia can be told they are 80% Icelandic due to being compared to you and you cohort?

These are their comments

Researcher uses DNA to demonstrate just how closely everyone on Earth is related to everyone else (phys.org)

He’s wrong. Not everyone who had children 1000 years ago had grandchildren for example. Plenty of lines died out. It’s really basic stuff like that that calls into question their credibility on extrapolating their research at a population level to individuals.

That's not what he is saying.

It states that if people alive back then had ancestors alive now, then 1000 years ago, all of those people who still have ancestors today would be able to trace to all people alive now.

It's reckoned that is about 80% of the population alive 1000 years ago still have ancestors alive now

I don't think you are a tinfoil hat wearer at all <adjusts own shiny crinkly silver hat>

I actually know someone who works in this field and she is adamant that she would never hand over her genomic data to anyone. There's just too much that could be done in the future with it. To say nothing of the fact that they should be paying people for it, not the other way around, since that's the most valuable asset they have.

I am told by her that nothing going back 3 generations persists in the DNA to the extent that they can tell you your precise heritage. Only a few extremely anomalous sequences, apparently, will show you anything useful, unless you really are interested in your great grandparents, whom you most likely knew anyway. But if you didn't - I get the need to know.

The main thing for me is that these tests have been used widely by racists in the USA who want to prove their white European bloodlines, and nowadays people working in the field assume that their target market is white supremacists. Not a club I want to be part of!

"The main thing for me is that these tests have been used widely by racists in the USA who want to prove their white European bloodlines, and nowadays people working in the field assume that their target market is white supremacists. Not a club I want to be part of!"

Someone needs to tell them that they are related to everyone on else on Earth until relatively recently in human evolution.

Oh - and someone needs to tell the Royal Family that who cares if they can trace their line back to William the Conqueror. Many people in the UK can. It's just that accurate records haven't been kept for most people.

Since when have white supremacists listened to sense?! Look at the shower we have in the UK with their nonsense about indigenous Brits

Given that Cakeorwine can't tell the difference between descendants and ancestors....

I also agree that there is a nasty undertone to "ethnically British". I am in a lot of FB groups for people in other countries who have ancestors who came from different parts of the UK and that's something that comes up regularly. They are the "proper Scots/Irish/Welsh/Yorkshiremen", the ones who were there for centuries and left to go to US/Australia. Their descendants are even more Scottish/Welsh than these recent immigrants from the Caribbean or S Asia.

There are a few posters on this thread who clearly know what they are talking about though.

I have seen their comments. It contradicts what they have written in their own paper.

As an archaeologist, in my humble opinion, the most useful thing aDNA is showing us currently is familial relationships amongst burial groups going back to the Mesolithic and in some cases, like a recent Viking study, two brothers who were buried in different parts of Europe or men having children with several different mothers and vice versa or monogamous relationships. These things are absolutely fascinating and something we could never get at otherwise.

The whole 'ethnically British' thing is so bloody weird. There's been wave after wave after wave of immigration to Britain, nearly everyone has added a bit to the culture and a bit to the language (or a lot). I suppose at some point there was a group that arrived and could be called 'the first' who became indigenous (?) but we're talking ten thousand years ago.

I can trace my family back to a small area, all of them, both sides, we were there for generation after generation. I kind of found this funny because almost my entire family still lives in the area (some left and returned) and I used to joke it had some sort of atavistic pull on us. But I don't say it any more because it sounds like I class myself as an indigenous Brit and those people are just vile and ignorant.

That's not a very helpful response.

Do you accept the hypothesis about every European who lived about 1000 years ago and who have an unbroken line is also the ancestor of every person living today with European ancestry?

And if you think that's wrong, then it would be great to hear your reasons why.

There is of course genetic evidence that you can tell people on FB groups who go on about being "proper English" that they are in fact related to everyone else in the world by people in the not too distant past and also evidence that they are all related to every European who lived about 1000 years ago.

So I would have thought that if you wanted to "silence" them, then that evidence would be very powerful.

Do you read what you post? This is what you said.

”"Our research confirmed what Chang suspected—that everybody who was alive in Europe a thousand years ago and who had children, is an ancestor of everyone alive today who has some European ancestry," Ralph said”.

And my response is

He’s wrong. Not everyone who had children 1000 years ago had grandchildren for example. Plenty of lines died out. It’s really basic stuff like that that calls into question their credibility on extrapolating their research at a population level to individuals

I also call into question your credibility in not appearing to know the difference between ancestors and descendants. I don’t know why you’re so obsessed by this one paper from over 11 years ago. Their analysis of genetic interconnectedness of populations is interesting from at a population level but as far as I can make out they are massively overstretching to apply it to individuals because they are not taking into account all the factors described already in this thread. Such as stratification of societies, the lack of mobility. Theres also huge areas of bias, for example they only sampled people in two locations!

"e’s wrong. Not everyone who had children 1000 years ago had grandchildren for example. Plenty of lines died out. It’s really basic stuff like that that calls into question their credibility on extrapolating their research at a population level to individuals"

You did read this bit?

"Our research confirmed what Chang suspected—that everybody who was alive in Europe a thousand years ago and who had children, is an ancestor of everyone alive today who has some European ancestry," Ralph said"

You did read the bit where it says "and who had children" - he could have said "had a line that continues to the modern day" - it's reckoned that about 80% of people alive back then have modern descendants.

"I also call into question your credibility in not appearing to know the difference between ancestors and descendants"

Really? And what are you basing that on?

" I don’t know why you’re so obsessed by this one paper from over 11 years ago"

Because it's the one that is quoted when you do research on the genetics of this.

1000 years ago is a very long time - and it doesn't take much to build up a large family tree. Even with everything mentioned on this thread.

Ok, I’m out. @cakeorwine you can’t even be consistent within your own posts. It’s like trying to debate with a cat. I am reminding myself of the futility of online debate.

Our family looks fairly white, but we have an Indian grandmother (although she was never forthcoming if she was mixed race (she was very light skinned) and my father was Welsh - born in Wales to two Welsh parents - but in an area which had a lot of migration from SAm.

My brothers and I did one one Christmas and they weren't similar enough to each other to be potentially true. I was more similar in genotype to my half brother than my full and there isn't an issue with paternity.

I suspect they googled our names and then worked out the genotype from that.

I am quoting from the research.

If you disagree, then fair enough.

It is the paper that is quoted and the research that is quoted and has been peer reviewed.

It's in Scientific American and other respected journals.

You can disagree but it's not been argued against in any science journal I can find.

So it's the working hypothesis. Maybe you should edit the Wikipedia page for it if you think it's wrong.

Identical ancestors point - Wikipedia

@nonumbersinthisname Oh, god. Sometimes XKCD gets it exactly right. I’m saving that one, ha. But yes, it can be really hard to disengage. Even now, there are so many points still to be argued SO easily, I know, but it will never stop, so sometimes the healthiest thing to do is just leave. Hats off to you.

Feel free to leave

Someone quoted Mark Thomas - this is him giving a lecture on genetic genealogy and he quotes EXACTLY the same evidence. To genealogists

It's at 15 minutes in

If you don't like to have actual scientific evidence given to you that contradicts your views given by geneticists in scientific papers and at conferences to genealogists, then fine

You can also read this

DNA, Genealogy And The Search For Who We Are : 13.7: Cosmos And Culture : NPR

And you can read UCL on genetic testing.

Understanding genetic ancestry testing | UCL Division of Biosciences - UCL – University College London

The lecture looks interesting.

A screenshot

Maybe this geneticist should be told he's wrong as well

@cakeorwine

HINT: You’re allowed to change your mind in science.

MY PROOF: 2023.

YOUR PROOF: 7 years old, 9 years old, 11 and 12 years old, and the block for it is 25 years old (Chang).

I think it was the OP who claimed to be a genetics expert, not you. But people who are really interested in genetics would not be so resistant to changing their minds. They’d be interested and intrigued. Learning more is not illegal.

I’m sorry that you seem to feel (or at least you’re acting like) it is.

And since you’ve told me to feel free to leave, I’m gone, nonumbers is gone, Misthios is gone, and it’s my sincere hope that no one else will give you the argument you want, for no reason.

It’s just new research. Why is it such a personal threat to you?

Is your article about DNA inheritance?

"I shared an actual scientific study that used the DNA of several individuals known to be Vikings. Results: only 6% of British people have Vikings in their ancestry. What would you like me to do about it? You may have Celt, or Norman, or Saxon, or Moor, or maybe even Nordic - and 6% have Vikings."

The genetic history of Scandinavia from the Roman Iron Age to the present: Cell

That's different to having ancestors though - as has been explained, *you can have ancestors but you might well not have DNA from them. But you do have a link through a "bloodline"

Correct - not many people in the UK will have Viking DNA. That's what your paper shows.

However - all people in the UK with European ancestry are related to every European who was alive 1000 years ago and whose line has survived. That's different to the DNA study though - as DNA gets mixed up etc.

This is the link to the current work from UCL by Mark Thomas on this.

Have you read it?

I would watch the video as well.

Molecular and Cultural Evolution Lab - UCL – University College London

I think you have been thinking about actual DNA and genetic inheritance - which the study looks at.

I have been talking about following a traceable line down parent to child etc. Which most people in the UK can do from the Vikings. Or the Normans.

And if anyone still is interested in genetic genealogy, there are a whole load of links here on the genetic genealogy Wiki page from the International Society of Genetic Genealogy.

(Including several that I have linked to. And to Mark Thomas)

Genetic ancestry - ISOGG Wiki