Massive Study Searching For Genes Behind Intelligence Finds Little 269
An anonymous reader writes: It's been taken for granted that science would, one day, figure out what parts of our DNA make us smart (or not). But a huge new study done by a group of almost 60 researchers using genome data on over 100,000 people has come up empty-handed. The scientists first looked for differences in the genome that correlated with academic achievement. After narrowing it down to 69 individual sites, they gave cognitive tests to separate group of 24,000 people and looked for evidence of difference at those same locations (abstract). Most of the sites weren't significantly different from chance — the (already weak) genetic influence of genes on height has an effect 20 times greater. On top of that, the three gene locations that did seem to have a stronger correlation weren't involved in development of the nervous system.
Great news (Score:3)
GATTACA becomes a little less plausible!
But what of this story?
http://science.slashdot.org/st... [slashdot.org]
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Yes when I saw that news in the summer I thought it was misguided. I did a short essay on genetics vs environment as part of my psychology education where the conclusion was that environment dictates the IQ of children and genes the IQ of adults. The cause of this might be that adults choose and form their own environments.
This might mean that environment is the biggest factor in the average person's intelligence, but that their genes affect what type of environment they choose to have.
Personally I think th
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sounds more reasonable
So... you have no idea, then.
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Just because they don't know where to look, doesn't mean it's not there.
Probably, there are a great many genetic factors that could play a direct or indirect role in intelligence, either for the better or for the worse.
Also... let's not discount things such as eating habits, and nurture --- discipline, motivational factors, inspiration, culture, etc.
And the fact that it might be genetic, but 50,000 people might each have totally different genes contributing to their higher intelligence.
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Just because they don't know where to look, doesn't mean it's not there.
They looked everywhere, they found nothing. They weren't looking for a meaning, just a correlation. The correlation they found accounted for about half an IQ point, which is insignificant in the grander scheme of things. Perhaps there are genetic markers that predispose you to intelligence, but the point is that our society does not favour those with them, and in fact renders any such factors null. The assumption that people of higher social status often make, that their family has been successful because t
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But what of this story? http://science.slashdot.org/st [slashdot.org]... [slashdot.org]
The scientists in that story also failed to find specific genes affecting the skill levels (they looked). In other words, they found a correlation, but not a causation.
Re:Great news (Score:5, Insightful)
Re:Great news (Score:4, Insightful)
"Massive study finds that they should have hired more intelligent researchers"
Who cares if they found genes correlated to intelligence but they don't directly affect the nervous system? The body is interconnected in so many ways that everything affects intelligence.
Also, academic achievement also tests for willingness to put up with bull and do boring homework, or an interest in certain subjects. To be fair though, academic achievement is probably more important than intelligence, at least for some things. For example many colleges want applicants to take the Student Aptitude Test, yet I've never heard of one wanting an IQ test.
Other studies have found that about 50% of the variation in intelligence is due to genetics. This study only looked at it from the perspective that maybe a few genes contribute a lot. It seems that the answer is it is due to a large number of genes each with a tiny effect. This is hardly surprising but it was a worthwhile test.
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Yup. They assume a direct relationship between "intelligence" and academic achievement. There ain't.
While it's unlikely that someone with an IQ of 80 will go on to great academic achievement, there's no guarantee that someone with an IQ of 130 will either. Plenty of high-IQ folks who got too bored with school and dropped out, or sidetracked by something which caught their interest so that they neglected their studies, etc. Probably most high academic achievers have high(-ish) intelligence, but the
Re:Great news (Score:5, Funny)
I've got great news for you... you're already a big dick.
Re:Great news (Score:5, Insightful)
"Its central argument is that human intelligence is substantially influenced by both inherited and environmental factors and is a better predictor of many personal dynamics, including financial income, job performance, chance of unwanted pregnancy, and involvement in crime than are an individual's parental socioeconomic status, or education level."
And
"The debate about whether and how much genes and environment have to do with ethnic differences remains unresolved."
It's a perfectly valid premise to investigate. That's all the book is. Just like some groups have predisposition to certain diseases, maybe some groups have a genetic limitation to the likely of above average intelligence.
Please note: I am saying some groups. I am not saying my group would be smarter. People tend to project that idea.
That said, I hope not. But not looking into it is a massive disservice to humanity.
Re:Great news (Score:5, Insightful)
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What criteria were they using to define intelligence? How quickly people learn, or general ability to retain information or what? Because someone raised by wild dogs and someone raised in the finest educational traditions of modern society are going be at very different levels of intelligence no matter how you slice it.
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That debate was resolved long ago: ethnicity does not influence intelligence per se. However, other factors may cause a correlation. For example, if Indians coming to the US frequently work in high tech, then in the US, Indian ethnicity will correlate with higher intelligence, even though the total populations of Indians in the world score lower than the total population of Americans.
Re:Great news (Score:5, Informative)
maybe some groups have a genetic limitation to the likely of above average intelligence.
There is no maybe, every study that has ever looked into this since the dawn of science has confirmed this. Hell you don't even have to ask science, every average Joe on the street knows this already from life experience.
It's just in the last ~20 years that political correctness mass hysteria has gripped academia and the media to where it's become a thoughtcrime to think any other thought than that all races are exactly equal in every aspect except maybe skin melanin level.
And it's just the United States and a couple of other Western European countries afflicted with this weirdness. If you were to go to, say, Japan or Russia and say to a scientist, "Some races have higher genetic disposition for intelligence than others", he will most likely shrug and say "Yeah, so what?"
But just in case you're young and everything you've ever read has been sanitized by the Academic Department of Purethought: the highest average IQ of any human race/group belongs to Ashkenazi Jews.
Re:Great news (Score:5, Insightful)
There is no maybe, every study that has ever looked into this since the dawn of science has confirmed this.
Indeed. For example, even the ancient Greeks and Romans knew perfectly well that these uncouth blue-eyed barbarians from the North were obviously dumber than the glorious Mediterranean master race.
Wait, what?
Hell you don't even have to ask science, every average Joe on the street knows this already from life experience.
Ask "average Joe on the street" what he thinks about evolution.
Re:Great news (Score:4, Insightful)
Ask "average Joe on the street" what he thinks about evolution.
Exactly. Relying on average Joe to determine a piece of knowledge on very complex shit (or wisdom) is pretty stupid no matter how we cut it.
Re:Great news (Score:5, Insightful)
maybe some groups have a genetic limitation to the likely of above average intelligence.
There is no maybe, every study that has ever looked into this since the dawn of science has confirmed this.
Your statement may be accurate, but probably not in the way you mean. If you seriously want to look into the history of scientific views on race, you might start here [wikipedia.org].
Yes, for most of the history of science, scientists have claimed that they had "proof" of the inferior intelligence of one race or another. The funny thing is... the race that is "stupid" tends to change depending on the time period or the background of the authors, suggesting most historical methodologies were probably flawed. Unless, of course, you actually believe that the Jews and Asian people of the 19th century were actually so very stupid (as scientists of that time said), but recent IQ tests seem to put them at the top. And if you believe that all these scientific "tests" are valid across different eras (which is rather preposterous if you look at their "methodologies" for determining "superior" races), then your genetic heredity hypothesis runs into problem -- otherwise, how do you explain the giant jump in intelligence for Asians and Jews in "scientific" studies in the past couple hundred years?
It's kinda like the fact that back in the early 20th century, Jews were the stars of professional basketball [thesocietypages.org], lauded for their supposed athletic prowess, their craftiness and stealthiness ("scheming minds"), and their shortness, which was supposed to give them an advantage on the basketball court by allowing faster maneuvering closer to the ground. Of course that sounds like nonsense today when basketball is dominated with large, tall African-American players, but we still seem to want to find some sort of genetic explanation for the "natural athletic ability" of certain races.
Hell you don't even have to ask science, every average Joe on the street knows this already from life experience.
I know average Joe. He often harbors some racist views, either overt or latent.
But just in case you're young and everything you've ever read has been sanitized by the Academic Department of Purethought: the highest average IQ of any human race/group belongs to Ashkenazi Jews.
The problem is that you have to accept that (1) IQ tests actually are a reasonable measure of the only type of "general intelligence" that counts, (2) that IQ can't be influenced significantly by experience or life conditions, and (3) that there are no other confounding variables that could make comparisons between vastly different groups problematic.
I don't accept any of these. First, IQ tests measure something but many scientists have severely criticized them [wikipedia.org] as the only possible measure of "general intelligence." And second, there are many, many known confounding factors [wikipedia.org], including environmental factors and life experience, that make comparisons difficult between races.
I'm NOT saying that no racial differences exist. I'm saying that (1) even if they do exist, the tests are mostly written by smart white people to evaluate smart white people, so they may not accurately measure useful intelligence in other cultures, (2) there are way too many confounding variables to give a lot of accuracy to comparisons, and most of the differences seen at face value are very likely not to turn out to have meaningful genetic or racial sources.
If you were to go to, say, Japan or Russia and say to a scientist, "Some races have higher geneti
Re:Great news (Score:4, Interesting)
Well, life imitates art, and what was once a fanciful Sci-Fi movie can turn surprisingly real surprisingly quickly. (E.g., the original Robocop - 30 years ago, it was unusual for police to have body armor and all sorts of military hardware. Then fast forward to today where it's standard issue. Nevermind much of what was supposed to be inane commentary and TV ads becoming real TV and products today. ).
It's good to disprove what is presented as fact, but it's also important to realize that what was fiction yesterday can be truth today. Especially how cheap genetic testing is becoming these days, we're not really that far away when genetic testing becomes an incredibly routine part of one's day where you're tested 10 times a day for ID and other purposes.
Hell, 1984's fiction, too.
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I don't see where the book was ever debunked.
Just criticized by the perpetually butthurt politically correct social justice warriors. And we know what mere criticisms are worth. Everyone has one.
Re:Great news (Score:4)
A significant portion of the book is based on statistical correlation. The book makes multiple references to Mankind Quarterly [wikipedia.org].
The issue is not whether science can or should study this. It is the dangers of doing so using bad science then packaging up unsupported results and presenting them in a way that justifies harmful division in society on a foundation built of sand.
If it were serious science, it would surely have looked beyond Caucasian Americans and investigated the intelligence of Asian Americans too.
Re:Great news (Score:5, Interesting)
It's actually a rather decent book. You should read it. It has other insights which are equally
intriguing. Like the fact that most people's friends and coworkers tend to be close in intelligence,
socioeconomics, etc... Most people with college degrees are surrounded by people with
college degrees. Heck, 1 in 5 people don't graduate from HS but if you have a college degree
I doubt you can name a single friend you have that doesn't have a HS degree and I would be
very surprised if you could name 5 unless you happen to work in an occupation that crosses
boundaries. This clumping is probably just as much a factor as many other factors people
tend to look at. We try to pretend we have a classless society but when a person with a
130 IQ only hangs around with other people with a 130 IQ they get a very skewed view of the
world.
In a related story, (Score:2)
Not a huge surprise to me. (Score:2)
My parents are both dumber than dirt but I'm way smarter than them.
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LOL.. That will change as you get older young grasshopper.. You will find your self dumber and your parents smarter as the wisdom that comes with age sets in.
If you have kids, they will look at you the same way.
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So you're ... dirt?
Wait: Genes do not strongly determine height??? (Score:5, Informative)
the (already weak) genetic influence of genes on height has an effect 20 times greater
Wait... did I just read that genes only have a weak influence on height?????
Googling "genes for height"
Height clearly has a lot to do with genetics [ox.ac.uk] - shorter parents tend to have shorter children, and taller parents tend to have taller children...
Okay, phew! I must have misinterpreted the meaning of "already weak genetic influence." Also, each of those articles do go on to explain that nutrition, including fetal nutrition, have a significant impact as well.
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This is from the New Yorker [newyorker.com], not a scientific paper certainly, but it's interesting and relevant nonetheless. It may explain some of the comments regarding genetic and environmental factors.
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Shorter parents tend to have shorter children for one or two generations, then it oscilates to the other edge, and a generation with taler children shows up.
Certainly the range in height is partly determined by genes, however the main factur is nutrition of the mother and the embryo and later the born child itself.
Traditionally, 100 years back, all italians, greeks and spanish people where considered small. Meanwhile north Italy is dominated by tall people, and regardless where I go, with my 172cm I'm just
Looking in the wrong place (Score:2)
Did they look at the CVs of those 100,000 people? How many of them were PhDs? How many were prolific inventors? How many where self-made *gasp* one-percenters?
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"How many of them were PhDs? How many were prolific inventors? How many where self-made *gasp* one-percenters?"
none of which is an actual indication of intelligence.
It's likely to be a strong indication of motivation.
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self-made *gasp* one-percenters?
There's no such thing. Everyone with that kind of wealth either inherited it or got extremely lucky. Its not possible to become mindbogglingly wealthy through hard work and diligence; there's no such thing as a "self-made millionaire".
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I don't think it's narcissistic. This reads like "please validate the ethical value I've invested into Social Darwinism" to me.
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Having poor fine motor skills in no way indicates intelligence.
"See who's smart enough to simply survive."
Simple surviving does not require above average intelligence.
Maybe... (Score:3)
...the brain really is just for cooling the blood after all.
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Just after Sarah Palin had me convinced it's some kind of hair growth medium...
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academic achievement as a proxy for intelligence (Score:2)
That choice of proxy needs some support, lest they end up accidentally gathering evidence that earning a 5.5 GPA in basketweaving does not correlate with unusual genes.
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My first thought, exactly. Who would have thought that academics would equate intelligence (and other admirable traits, as well?) with academic achievement? Are there other ways in which this innate component of intelligence can manifest? Might cultural and socioeconomic factors - among other things - muddy the association?
Intelligence is highly heritable (Score:5, Informative)
"Convergent evidence from a set of bioinformatics analyses implicates four specific genes (KNCMA1, NRXN1, POU2F3, and SCRT). All of these genes are associated with a particular neurotransmitter pathway involved in synaptic plasticity, the main cellular mechanism for learning and memory. "
Intelligence is highly heritable, but there is no single 'genius' gene and often there are multiple genetic markers that have similar positive or negative effects. This study looked for common genetic variants that correlated with memory and learning and found them!
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The problem is that they don't completely (or sufficiently) explain the variation that is seen.
Re:Intelligence is highly heritable (Score:5, Informative)
RE:GOALPOSTS (Score:2)
No, I'm not.
I mean, of the predictive utility of what they have discovered is presumably real. But the point I'm contesting is your central thesis that "intelligence is highly heritable". Which is not what this study found. Correlations of intelligence to (these) genetics, even on multivariate examinations, is weak. Thus your "intelligence is highly heritable" comes of as reductionism.
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Since we are nitpicking, you are also incorrect by stating that "the predictive utility of what they have discovered" - they have not performed exhaustive search for all genes that would positively
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Now that is moving the goalposts. But that's okay, I understand the point you're trying to make, and I don't think it's unreasonable to expand to such a search. Just don't expect me to grant you the premise that it's a likely explanation.
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The summary indicates they did not just want to find evidence, but the genes.
Which can be very tricky if those genes are more related to the metabolism, e.g nerotransmitter production, digesting of amino acids, transports to the brain, a minimal better lung (without exercising) and better oxigen distibution.
There might be hundrets of factors which all only contribute a very small thing.
Bottom line intelligence/talent brings you only so far. More important is knowledge, facts and 'procedures'.
You can be as t
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If intelligence was hereditary, it should be trivial to point to a family of increasingly intelligent people who should reach their pinnacle about today.
The problem with Smart Genes (Score:5, Funny)
The genes are obviously smart enough to hide from researchers.
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The genes are obviously smart enough to hide from researchers.
And you.
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No, I know where they are. They just bribed me.
Genes are just the "hardware" (Score:2)
And as we know, the hardware is only half the battle. The "software", or in case of intelligence, the actual processes and the way the brain actually works and develops during the life time, is still mostly unknown to us. It's a bit like studying the processor chips from any give age, and trying to "sort" them, or find a way to "classify" them by performance, without actually knowing how or what software then can run.
As with some other things in life, the genes might give you a "framework", or a starting pl
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"And as we know, the hardware is only half the battle."
no, that's the point. Is it half? or is it 20%? 70%? 0%? Is it having more of a certain protein type that 'walks' the DNA chain?
Is it just getting interested in something at a young age develops your brain in different ways? some of each?
Does any one see it? (Score:3)
Did they try looking next to them? (Score:2)
So they were wrong in their hypothesis that these 69 sites on the genome are related to intelligence. This does not mean that other sites on the genome aren't related to intelligence.
On top of that, the three gene locations that did seem to have a stronger correlation weren't involved in development of the nervous system.
So they really don't have complete knowledge of this extremely complex system. Not surprising. Time to review their assumptions, and come up with a new hypothesis to test. They still gained knowledge (what doesn't work), it's just not the knowledge they were hoping for.
Probably numerous different independent genes (Score:2)
With "smart" people ranging from type-A personalities, to high-functioning autistics, it's not surprising they wouldn't find one specific set of genes for intelligence. There is extreme variation in "smart", and even more for "academic achievement", where a complete idiot (for lack of a better term) willing to put in substantial effort, can perform just as well as a highly intelligent person without such motivation.
Achievement is not intelligence (Score:2)
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Article is totally misleading (Score:4, Insightful)
From the original paper:
http://www.pnas.org/content/ea... [pnas.org]
We identify several common genetic variants associated with cognitive performance using a two-stage approach: we conduct a genome-wide association study of educational attainment to generate a set of candidates, and then we estimate the association of these variants with cognitive performance. In older Americans, we find that these variants are jointly associated with cognitive health. Bioinformatics analyses implicate a set of genes that is associated with a particular neurotransmitter pathway involved in synaptic plasticity, the main cellular mechanism for learning and memory. In addition to the substantive contribution, this work also serves to show a proxy-phenotype approach to discovering common genetic variants that is likely to be useful for many phenotypes of interest to social scientists (such as personality traits).
How the hell does the article now writes that "The scientists first looked for differences in the genome that correlated with academic achievement"? No, they looked for "educational attainment". Then the abstract goes on "Three SNPs (rs1487441, rs7923609, and rs2721173) are significantly associated with cognitive performance after correction for multiple hypothesis testing." SNPs are different alleles of the same gene.
Then, "Convergent evidence from a set of bioinformatics analyses implicates four specific genes (KNCMA1, NRXN1, POU2F3, and SCRT). All of these genes are associated with a particular neurotransmitter pathway involved in synaptic plasticity, the main cellular mechanism for learning and memory." But the article states that " On top of that, the three gene locations that did seem to have a stronger correlation weren't involved in development of the nervous system."
What the hell??
In other news.... (Score:2)
First - Find a real test for "intelligence." (Score:2)
I think (Score:2)
So nurture has something to do with it too, so too education.
Epigenomics. DNA doesn't account for everything (Score:2)
Finds little intelligence? LOL (Score:2)
What's intelligence have to do with it? (Score:3)
They weren't trying to correlate intelligence with genes. They were trying to correlate educational attainment with genes. That is not the same thing. People don't always apply their full intelligence towards school. Also, doing well and going far in school doesn't prove much about one's intelligence. It proves one can remember facts long enough to regurgitate them in a test. I suppose that is a kind of intelligence but there is much more to it than that! I think that having an analytical mind and actually thinking about those facts can get in the way of the study, regurgitate, forget, repeat process and is therefore detrimental to one's grades.
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They were trying to correlate educational attainment with genes.
That should have been easy. If daddy is successful, you get into the best schools.
Perhaps this demonstrates what a lot of people already suspect: If daddy spends his entire life at the office, making money, odds are he's not really the daddy. Better to correlate intelligence with the pool boy.
From the summary... (Score:3)
Poor Study (Score:2)
abstract is rather different (Score:4, Insightful)
The AT article seems to try to put a spin on it, but the actual abstract sounds quite different:
It's clear from twin studies that IQ has a strong genetic component [wikipedia.org], about as strong as height: both have a heritability of around 0.8 (on a scale from 0 to 1, with 1 being variability being entirely genetically determined). Here's a bit more info on heritability from Nature: http://www.nature.com/scitable... [nature.com]
Failing to find the genes responsible in this study means nothing since the current SNPs we test for are quite limited. Ultimately, these questions can only be resolved by full genome sequencing of large numbers of people. Until then, we may get lucky in identifying genes in these kinds of studies, but failure to find something means little. And, actually, they did find something interesting.
Re:abstract is rather different (Score:4, Funny)
I was about to post something similar. The spin is quite strange given the reading of the abstract.
FWIW, I believe the original study that identified the 3 SNPs in educational attainment is here [nih.gov], but as mentioned it's a very weak statistical correlation as it only contributes to about 1 additional month of schooling on average. Also the assumption that the genes vary in terms of SNPs is also a big assumption which may be false too.
Basically, they seem to be mostly saying it's unlikely that a small mutation (because that's what a SNP is mostly) that was selected/amplified by evolution can determine our intelligence. That's really baby steps in this question.
Perhaps some sort of DNA methylation which is correlated with in-utero nutrition levels interacts with the underlying DNA expression somehow that is a better proxy for what we think of as intelligence (which is only weakly correlated with academic achievement). If so, we probably aren't going to find it by this technique at all. Kinda makes this total non-news in my book.
There's a perfectly logical explanation ... (Score:3)
They're all a bunch of idiots.
We do not understand intelligence at all (Score:3)
That is does not seem to be genetically just adds to the mystery. But there are other failures: While intelligence can be described by its effects, there is no theory at all how it works. The only existing model (automated theorem proving) is severely limited both by the nature of what it can do (construct mathematical theory) and by its inherently exponential effort which means it will never be able to do in practice hat smart human beings can do routinely. Then there is this little problem that intelligence has only been observed coupled with self-awareness and may also be tied to "free will", another two things that are not understood at all. Granted, most people are not really adept at using what intelligence they have (which routinely is also not that much), but it is still a defining quality for being a human being. It is really surprising that this quality proves intractable time and again.
Now, there is a branch of religious fanatics called "physicalists" that insist everything is just "chemistry" or "physics". These people routinely vastly overestimate what is known scientifically and seem to be completely unable to deal with some rather fundamental things being unknown at this time. All typical characteristics of the religious fanatic. It is rather ironic that there people usually claim to be anti-religion and pro-science, when they have in fact invented their own disconnected-from-reality fantasy. These people usually neither understand the scientific process, nor what is known to science at this time. My take is they are people that sort-of understand that religion is bogus, but actually cannot be without it end hence invented this surrogate.
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Well, sorta.
There's a lot more evidence that in-utero nutrition has a big role to play on intelligence. In fact, it's a commonly cited possible causal mechanism behind the Flynn effect.
So... you might be born with dramatic differences in your eventual (general) intelligence already in play, but that doesn't necessarily implicate genetic determinism.
Also intuitive is the fact that genes do play a role in the difference between human intelligence and apes. Just not necessarily between humans. So genes do s
Re:In other words nobody is born smart (Score:4, Insightful)
The study did not demonstrate this at all. It simply failed to find specific genes responsible for intelligence.
You might still be born with a set intelligence which isn't genetically determined, or it might be genetically determined on the basis of genetic factors that were not identified for any number of reasons. Or you could be right.
The point is, this study doesn't provide any evidence one way or another.
Also, equating academic performance with intelligence may be dubious. There could be many factors responsible for academic performance, of which intelligence is just one. We can't even define what intelligence is...
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Not quite true.
It shows that a large number of specific candidate genes don't do it. Even if it's not a complete refutation of the hypothesis, it is a push to maybe look elsewhere for some of the mechanisms of intelligence development.
Re:In other words nobody is born smart (Score:5, Insightful)
Not quite true.
It shows that a large number of specific candidate genes don't do it. Even if it's not a complete refutation of the hypothesis, it is a push to maybe look elsewhere for some of the mechanisms of intelligence development.
Well, it only would show that those genes don't have an individually-detectable affect on whatever marker they looked at. Maybe collectively they have an effect that can't be detected statistically. Maybe the marker they chose doesn't make sense.
Imagine if I tried to identify the gene for "sickness." I took anybody who ever got sick for any reason and studied their DNA and looked for a common link. Most likely I wouldn't find anything. Would this prove that genes can't make you sick? Or is it more likely that "sickness" is such a broad description of a phenotype that it could have a billion different causes.
Academic performance could be the result of MANY factors. Physical attractiveness has been demonstrated to have an impact on academic performance, and you'd hardly expect the same genes to affect that as your ability to do some kind of mental processing. That is just picking one attribute that is obviously going to confound results. Then you get into stuff like whether intelligence is about persistence, or ability to process information, or memory, etc. All of those things are likely to affect academic performance. Then there are cultural factors - let's just assume the sterotype about Asians prodding their kids to study harder is true - I'm sure there are alleles more common in Asians (the fact that they have distinctive appearances makes this obvious for starters), and that is going to confound things.
If you really want to identify the genes responsible for a trait, you have to first come up with a very precise definition for the trait, ideally one tied to some kind of biological mechanism (good luck if it involves the brain).
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Nope. Some people are born smart, or dumb. Mostly average. Why is that? that's the question.
Re:In other words nobody is born smart (Score:5, Interesting)
The counterpoint here is twin studies. Identical twins, born to the same parents, but adopted by different families, tend to have extraordinarily unlikely similarities in adult general intelligence scores. What this study has been undermining is the notion that because it tracks from birth, it has mostly to do with genes.
Instead, this suggests there are other conditions that identical twins share besides genes. As I said in my earlier post, a lot of expertise has been focused on in-utero development instead.
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Identical twins only separate at birth, so all we've got evidence of is that intelligence is largely set prior to that event.
I'm going to guess that we really need to studied identical twins, separated PRIOR to implantation and carried by different mothers. Problem with this is such experiments are not exactly ethical.
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Not necessarily. Natural experiments for individual genes like this one can be conjoined with careful observation of fetal development, and maybe lead us to some useful conclusions(whether they be positive or negative for the hypothesis I described).
Re:In other words nobody is born smart (Score:4, Insightful)
You could also just compare them with fraternal twins.
In this case the genetic starting points are different, but the in-utero contributions are the same.
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Unfortunately, with fraternal twins, there are two umbilical cords and two placentas... so there can be variance in nutrition and oxygen... heck, even with identical twins oxygen levels can vary. Still, it WOULD be an interesting study.
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Spoiler, they have [newscientist.com], and the results are... less than fully informative.
From a purely genetic basis, whereas identical twins have a 95-100% similarity on these things, you might expect a 50% similarity from fraternal twins in a purely genetic environment. Instead, it comes out to 70%, which suggests other factors playing an important role. However, because these are non-isolated from environmental factors(i.e. raised by the same parents), we can't use it to precisely tamp down the amount of a role genetics
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But you do know that 'identical twins' spring of from one single egg?
So implanting this egg into two mothers raises quite more ethical questions than a simple mind might assume.
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Identical twins, born to the same parents, but adopted by different families, tend to have extraordinarily unlikely similarities in adult general intelligence scores.
Which is it - academic performance, or general intelligence scores? If the twin studies test one, and this genetic study tests the other, then I would think that this would make it very difficult to draw any conclusions by comparing the results, since academic performance and IQ aren't the same thing.
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General intelligence [wikipedia.org] a slightly more robust tool than IQ for measuring intelligence abilities. So neither.
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Did those twin studies include twins that were separated into different socioeconomic groups? Or just different families, but similar socioeconomic status?
I have a feeling it all comes down to socioeconomic status. You end up with a better diet, better learning environment, etc. Its not necessarily the status itself that gives the better outcomes, its all the extra benefits that status provides.
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It does not all come down to status, though it does have predictive value. And you really shouldn't expect it to, since status is, at its best, an approximate proxy for a number of environmental factors, like parental involvement, education quality, medical care, nutrition.
All of those, in turn, can vary between different social and economic cohorts.
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People are 90% bacteria.
When we are born -- it's not just genes we get, there is likely a whole scaffolding system from the Mother that passes on Mitochondria to protein based information. It seems the search for intelligence has been too reductionist to JUST DNA and not looking at the embryonic stage where environment and mother switch on and off different components and equip the baby with a complex immune system, GI tract. It's like saying a "computer" is smart based just on the CPU and not paying attent
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> You're not born with it, you have to learn to be intelligent.
Unfortunately that doesn't account for examples where there are strong deviations from one generation to the next without any clear indication that environment was capable of being the deciding factor.
Actually, examples like those should probably be the starting point for work like this. This study may be full of not terribly useful examples.
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maybe the sun altered some DNA passed down through the ages.
Perhaps. But part of the evolutionary process is some sort of filter to select the most valuable mutations above others. I just don't see any evidence [slashdot.org] of that in modern society.
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At least some of the smartest people in the World think so.
I'm reserving judgement until I hear what their kids think.
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That dumb people breed like bacteria? Last time I checked that was still in effect.