Robert Plomin, Kings College London
Kat - We often talk about things being “in the genes”, from traits such as eye or hair colour to our risk of diseases. One of the main ways that scientists figure out how much a particular characteristic is down to genetics - known as its heritability - is by comparing identical twins, who share 100 per cent of their genes, with non-identical or fraternal twins, who only have 50 per cent of their DNA in common. Thanks to a unique study tracking thousands of pairs of twins as they grow up, Professor Robert Plomin and his team at King’s College London have now discovered that genetics makes an unexpectedly large contribution to children’s GCSE grades across a wide range of subjects.
Robert - In this twin study which we call the Twin’s Early Development Study which is a study of about 7,000 pairs of twins in the UK, I was interested in focusing on an area that hasn’t been studied much and that’s school achievement. So on the one hand, we know that cognitive ability like intelligence shows substantial genetic influence. But people hadn’t really studied the business end of it in terms of school achievement. And so, we were surprised to find from the very first years of school that school achievement as measured by the national curriculum scores. It’s very highly heritable, like 60 per cent heritable. That means, of the differences in children’s performance in the national curriculum test, over half of those differences between children are due to DNA, genetic differences, between them. So, we’re not identifying the DNA, but we’re using the twin method to estimate, not only the significance, but the effect size of genetic influence on school children. It’s very high.
So, we’ve been following them all along and now that they hit 16, we wanted to use the GCSE scores - there aren’t many countries where the same national tests are administered to everybody. And so, what we’ve found is the same sort of thing that GCSE scores are highly heritable. But what's new is that all the tests – there's over 80 subjects that people can take for GCSEs - and all of them are highly heritable. That surprised me because I would’ve thought the STEM subjects – science, technology, engineering, math – would be more heritable for some reason maybe because it involves intelligence to a greater extent than drama and art. This is just totally exposing my biases of course as a scientist, but it wasn’t true. They are all equally heritable. It’s interesting that scores are as equally heritable despite the fact that some children are getting tutors and going to schools that have prepped them for GCSEs. Schools – we make a big deal about schools - you just say what school our kids in explain far less than 20 per cent of the variance. Explaining 50 per cent of the variance with genetic differences is extraordinary when education totally ignores genetics. In teacher training or whatever, not a word is said about genetics. And so, I'm just saying genetics is very important.
But what's really novel about this study is a little bit harder to understand and that is to say, “Okay, genetics affects all of these GCSE subjects” but is it different genes for every one? Are there genes for drama, genes for music, and genes for math? And the answer is definitely not. The same genes are affecting performance on all of these GCSE scores. The differences are probably more environmental. If you're good at drama and not good at math, that’s probably more of an environmental thing. But the genetic action has to do with what's in common in performance across all of these things.
Kat - Is it not just that they're just generally smart? They’ve got good intelligence genes?
Robert - That’s what most people would say and so, what we did is we took out intelligence. We corrected for intelligence. You can correct scores for age and sex, and you can correct scores for intelligence. So, you can take these GCSE scores and make them independent of intelligence, statistically. And then the interesting thing was that we got the same results. So, everything is equally heritable, independent of intelligence, and what's even more surprising, again, it’s the same genes that affect all of those intelligence corrected GCSE scores. So what that means is that, your hypothesis is a good one that a lot of what the genetic correlation among all these GCSE scores is about intelligence. But what's amazing is you take out intelligence and you find, yes, there's still genetic influence, but it also works in a very general way and that’s suggests it’s like an academic ability, genetically driven academic ability.
Kat - When you say that this ability, this academic ability is heritable, does this mean that we can pin it down and say, “It’s this gene. It’s that gene. It’s this gene”? Can we find these genes?
Robert - Well, a first step in trying to find genes is to find something that’s heritable. The research over the last few years is saying that cognitive abilities and now school achievement is highly heritable, motivates people to try and find genes. But what we know so far from all of the life sciences is that for complex traits - that it’s not for the thousands of single-gene disorders that are very rare, but for the common disorders in medicine like cardiovascular disease or obesity, or psychiatric things like alcoholism and depression - they're heritable but they're not due to one gene by any means. We’re thinking now there's thousands of genes of very small effect which means it’s going to be extremely difficult to identify the specific differences responsible for the heritability. But it’s all part of a package. It would be nice if we’re just talking about a handful of genes - the genes for math or something like that. But if this is what we’re finding, then we’re just going to have to roll up our sleeves, get the strategies that will allow us to identify, not the gene or the few genes, but thousands of genes that are responsible for the heritability of these complex traits.
Kat - King’s College London’s Robert Plomin, whose study came out in the journal Nature Scientific Reports. We’ll be looking in more depth at his twin study - as well as other large-scale genetic studies - in next month’s podcast.
I am reading, "The Rise and Fall of the Third Reich" by William Shirer. I am sure that Reichs Propaganda Minister, Dr. Joseph Goebbels, would have eaten up this ridiculous excuse for a scientific analysis with a spoon. I wouldn't be surprised if Oswald Mosley, Edward VII, and Nigel Farage admired it as well.
I have no doubt that Goebbels would also have misunderstood the report.
One interview with an author on the paper mentioned that difference in school could account for a 20% difference in grades.
Had this author been truly interested in doing a proper experimental design he would have restricted his sample to twins who had been SEPARATED AT BIRTH. Since that may be a small cohort in the UK, he could have gone international and identified FOREIGN cases. That would have removed the obvious cultural bias which ALSO makes this study into such offensively racist twaddle. I have further doubts that the test sample is weighted to the same racial diversity as the UK population in the control sample. If, indeed, the "statistical" analysis was sophisticated enough to include a control group.
I'm just going to capitalise a WORD at random here to show that I can do it too.
I don't think that there is anything wrong with doing twin studies - the problem is more with how some people will try to apply the results.
It is all very well to say that the study should also include twins who were separated at birth. However, this study "accidentally" fails to do that - just as it "accidentally" fails to study across different cultures.
And, once again;Now, why don't you climb down from your high horse and actually answer my question.Feel free to explain why the identical twins have test scores that are more similar than those of the fraternal twins without using genetics.Just because you don't understand the design of the study, that doesn't mean it is wrong. It means that the variables you are looking for are automatically (almost entirely) corrected for. Bored chemist, Mon, 17th Aug 2015
"To tease out the genetic contribution to children's school grades, the researchers studied GCSE scores of identical twins (who share 100% of their genes) and non-identical twins (who share on average half of the genes that normally vary between people). Both groups share their environments to a similar extent."
And here's the actual article which I'm willing to be Bill didn't actually read.
The question of whether there is a genetic inheritance of intelligence -- or at least aptitude for dealing with the British classroom milieu -- to the extent that it depends upon intelligence or prosperity or the religion of one's parents -- is a serious one which deserves serious experimental design.
"The question of whether there is a genetic inheritance of intelligence -- or at least aptitude for dealing with the British classroom milieu -- to the extent that it depends upon intelligence or prosperity or the religion of one's parents -- is a serious one which deserves serious experimental design."
As to the supercilious slur that I have not read this paper it is not so.
OK, so you read it, but didn't understand it.
Upon reflection, I am removing my original comments here.
It really doesn't matter where you are from, or where the research was done does it?
and MY point is that in British class ridden society the idea of inherited virtue is a sacred cow which is worshipped enough to make such an ephemeral idea as one's parents matter.
Do you accept the fact that there is an inherited trait measured by the exam scores?
Until you have carried out a multiple regression study of a sufficiently large number of students you CANNOT truthfully say that inheritance plays a role in school test scores.
That's silly for a number of reasons.
If you can predict human performance based on inheritance, why can't you predict the winner in a soccer match by just consulting their family tree?
OK, so that's another strawman
This issue has been more than adequately addressed at this point. for anybody who lacks your cultural indoctrination.
You fight with the strength of many men, Sir knight....
If there were no genetic component in academic or athletic achievement, we would see the "whole population" distribution of extreme genetic anomalies reflected at all levels of every profession. But we don't.
Some people believe that a person's divine spark of humanity is determined to some extent by their genetic makeup. Those are the people T.S. Elliot was describing in his poem, "The Hollow Men" (1.)
This is exactly what Elliot was talking about in that poem.
I have never said that the effect matters; just that it exists.
Incidentally, did you not notice that not all of these people who you mentioned
T. S. Elliot was awarded the Nobel Prize in literature for his poetry in 1948. (1.)
In the Britain of 2025 if this publish-or-perish twaddle is remembered at all it will be in some obscure bits in some archive -- cited by nobody.
Not a great fan of Eliot - I have nothing against Americans (I live with the cream of the crop) and The Journey of the Magi is at least a good poem, but I dislike his politics and religion. As an apparent fan, however, you might be interested in the first Eliot quotation cited by Google:
That's all very well, but the question remains.
We of the chosen have already built Jerusalem in Europe, England, the USA, and most recently, Jerusalem for the second time. So to turn to your alternate hypothesis: after serving a dozen years on research ethics committees and a lifetime in laboratories and hospitals, I have grave doubts about the purpose and quality of most "academic research". Practically every paper in my own field (radiation protection and medical imaging) simply restates that photons travel in straight lines until they are absorbed by atoms, and "qualitative research" on the "lived experience" of car thieves, lefthanded lesbians, or whatever today's oppressed minority happens to be, is just a matter of transcribing a tape recording and nonjudgementally extracting a common theme from four interviews.
It wasn't useless.
As to the fraternal twins red herring, in any analysis one is free to throw out non-germane outliers. As much as you may claim that is a weakness , I have done so in my own good right. Let the readers decide as is <<their>> own good right.
The stats show that the effect is not an outlier. An dth e difference between the two sorts of twins is the essence of the study so it's just plain silly to suggest throwing it out.
I think that is, perhaps, the 14th time you have repeated that. Maybe you could try rhyming it next time.
You will be pleased to know that BBC3 is under threat of closure. Auntie has slowly realised that the sort of crap that appeals to people who make TV programs, doesn't always appeal to the people who watch them - at least not to the extent of justifying innumerable repeats. Thankfully, BBC4 is not yet under the cosh.
Since you yourself opened the matter and at the risk of inciting petulant shrieks of outrage, I will point out that given the obvious mental defects of Asquith, Lloyd-George and Clemenceau, it is quite understandable that the United States declined to drink the kool-aid until Germany went to sinking our ships.
In the real world - outside of Britain - people see that by not using twins who have been separated at birth these authors produced a bed-time story for smug white British gentlemen. This "scientific" paper got more coverage in the Daily Mail than any academic notice. That was no accident, Bub
Well, if you still think that "by not using twins who have been separated at birth these authors produced a bed-time story " you have still not understood the research.
Caveat Lector: Never discuss an issue of science which concerns something that has wide coverage in the Daily Mail with a certain type of Englishman.
Why does the finding that identical twins are more alike than fraternal twins appeal specifically to smug white British gentlemen? I would have thought it to be a common assumption among all people and fairly widely tested, at least anecdotally, by educators around the world. And given the anomalous incidence of twins in Nigeria, I would have thought the phenomenon would have been observed more often there than here.
Informed skepticism is the essence of the scientific method.
Behold, the dreamer cometh.
NOBODY in America would have touched this "scientific" study with a 10 foot pole because of its obvious racist and sexist nature. The fact that you people prefer to pretend that those faults don't exist, damns your case irretrievably.
By Gosh, I always thought that Ben Elton was dreaming up those characters in his stories. This thread is like finding long lost works of Wodehouse. THESE are the very same people Psmith encountered in those books. Go know!
Would you like to try discussing science for a change? Bored chemist, Tue, 1st Sep 2015
At what point in the paper under discussion was it suggested that anyone should be denied "a fair shot at an education" on any basis whatever? The paper discussed the variance of a few outcomes, and showed that it was significantly greater between heterozygous twins than between homozygous twins. What's the big deal?
It literally makes my skin crawl to discuss this with any British educated person who chooses not to see this "research" in its proper political, historical (and uniquely British) context.
Poisoned fruit from a poisoned tree.
"The reason that Burt's deceptions aren't mentioned in this paper is that the Charlatans and crooks behind it knew that it would weaken their snow job to bring them up. "
I think we must go along with Pecos Bill's logic, not least because he won't go along with ours.
Mr. Moderator Sir,
I wonder to which paper the honourable gentleman is referring?
In "The Mismeasure of Man" by Harvard Professor, Stephen Jay Gould we read of the shameful history of biological determinism (another term for the "genetic psychology" of this paper) from obvious fallacy like "Craniometry" right down to the ... Burt Affair.
I have been asked to avoid "ad hominem " comments. Then I will speak ad populem.
The history behind this "research" is telling in its nature but it was deleted.
I don't see why in this instance it's an either /or question. That identical twins results were more similar than fraternal twins doesn't seem to rule out that environmental factors could also significantly restrict or enhance their progress. cheryl j, Sun, 6th Sep 2015
Contrary to the simplistic assumptions of this research, identical twins do not share the exact same DNA The fact that these people fail to address this issue does not argue well for their candor and integrity.
As to the claim that these people don't presuppose that women don't match men in their GCSE scores....
Do you actually understand that there is a difference between
Humanity is sexist. There are boys and there are girls, they look different, have different chromosomes, and they have different biological functions. It turns out (not that anyone "presupposes" it) that they also get different scores in public examinations, which explains why the majority of medical students in the UK are female. For this reason it is important to correct for the underlying sex differences in various subjects if you want to maximise the yield of statistical data from twin studies.
In my opinion, women's different GCSE scores than those of men cannot depend on their DNA...
The gentleman states that since the majority of medical students in the UK are female this is evidence against gender discrimination because of their GCSE scores.
This topic on editorial control of the Naked Scientists show and Forum has been moved to New Theories.
In reading this thread, a tear was brought to my eye seeing that the Naked Scientists have shown how the genetic basis for paying women differently is absolute scientific truth. Of course British women doctors are paid 29% less because they are, ipso facto, genetically women. I mean, Duh! It's just what I intend to tell my new bride when she learns enough English to speak with the neighborhood women.
Thank God you have cleared that up, Sir!
Alas, you seem to be cut from the same cloth as that fellow Pecos. Curious chap, started off full of interesting information and searching questions, then got a bee in his bonnet about a paper he clearly hadn't read, tried to cover his embarrassment with irrelevant insults, and rather lost credibility. We scientists just say "OK, I was wrong" and get on with life, because science is all about having your preconceptions challenged by facts.
I recall Pecos_Bill saying that while people still struggle against sexism in America, they do not cook up phony pseudo science to claim it is due to genetic difference there. He made that point clearly shortly before he was eliminated by the forum's puppet master because it nauseated him (the puppet-master) to hear it.
Has British science not learned its lesson from Wakefield's recent autism/vaccination British crime against humanity? Guess not. Just as Burt's behavioral genetics crimes have now been swept under the rug. Too old and irrelevant , they say.
The fact that some people like Burt and Wakefield have been charlatans is well recognised.
If you want to sling mud at "British" science by quoting Wakefield, may I suggest a strong dose of Tuskegee as an antidote? Or is deliberate harm and negligence too tangential to be weighed against pathetic fraud? OK, let's get back to surgery: