And that is precisely what the “race realists” do not want to acknowledge. There is also something else, they also do not acknowledge that the research does look at the inheritance of intelligence, but not at the difference of intelligence among races, because in the case of the one bit that Richard Parker points out it is a gene that is present in all beings, even plants.
The research quoted also does point at environmental factors affecting the gene like a deficiency of succinate-semialdehyde dehydrogenase, that BTW causes mental retardation, genes are not the only factor.
No wonder the researchers also mention at studies that point at the differences that levels of poverty is making to the inheritance of intelligence.
Despite being less about the heritability of intelligence, that has also figured into these discussions a lot.
The broader context is the claim that there is “no evidence” (as opposed to merely claiming that the intelligence is unconvincing - which I tend to agree with) that intelligence varies by race. By insisting that “evidence” means the actual gene, this claim is boosted significantly, because this way unless someone finds an actual gene which boosts intelligence and shows that this gene varies by race the claim can be made that there is “no evidence” of genetic variation. As a byproduct of this approach, the more expansive claim has also been made that there is no evidence of genetic components of intelligence altogether, using the same process, as above.
Your syntax is a bit garbled, so it’s hard to tell precisely what you’re saying. Specifically whether you’re saying that no one has made this claim or that you and many others have not. Also whether you’re referring to the claim about a gene which would vary by race or a gene which is linked to intelligence altogether.
The conclusions from virtually all the research made on the inheritance of intelligence points out that that all humans have that capability. Sure that there are differences in the intelligence levels, but it stills points at the genes depending on a lot of feedback from the environment.
The genetic evidence is not as as well defined to justify the use of it for societal problems.
The study I cited said twins who are raised together have a correlation of .86 and those raised apart are .72. Non-biological adopted siblings are .29. Doesn’t that suggest that genetics account for well more than half the variation?
That is what the reference to a straw man should lead you to. Indeed, I have not made that claim, nor many of the experts I have seen on the matter.
I’m not excluding any possibility, but that is mostly a claim coming from the “race realists”. The point is that virtually all the research I have seen pointing at the inheritance of intelligence does not deal with race differences. Once again, all humans have that capability. The issue then for the race realists is to come with the genes that make the differences in intelligence among the races, repeating the evidence of the inheritance of intelligence like a broken record is not it.
I’m not making any claims about race. I’m trying to understand what the evidence has to say about heritability of intelligence.
And I have no idea what “all humans have that capability” means. I’m assuming you mean something like “we have no reason for thinking that any particular population has statistically significant variations in the relevant genes.” If so, I’m not questioning that proposition.
No one has claimed that genes are the only factor. Left Hand of Dorkness claimed that he was not aware that there was any genetic component to intelligence. That’s obviously wildly wrong. Genes exercise a significant influence on intelligence.
I think he just got carried away in knee jerk denial of everything, but I could be wrong, and he will be back to argue that all the studies are wrong. Or claim he was misunderstood.
That’s fine, but I wasn’t referring to experts. I was referring to posters on this MB, most of whom are not experts.
In this particular discussion the issue of “evidence of the inheritance of intelligence” was not brought up by a “race realist”, so your comment is not appropriate in context.
To the extent that this issue is relevant, it’s because it allows for the theoretical possibility that intelligence could vary by races. Not that it does, but it becomes a possibility. Once you’re at that point, then you need to make an assessment as to the likelihood that other factors could account for the observed differences. To the extent that you think the other known factors couldn’t account for the scale of the observed difference, then the genetic explanation becomes more likely.
Personally I am highly skeptical as to whether environmental factors can be ruled out, so I don’t tend to assume that the genetic explanation necessarily follows. But the general structure of the logic holds. If you think other factors are even less likely, then that makes the possibility of genetic factors even more likely.
Once you grant the theoretical possibility of a genetic factor, insisting that identification of a specific gene that varies by “race” and is linked to intelligence is required before anyone can make any assessment of the likelihood of genetic factors being part of the explanation is illogical.
Slightly misunderstood, but slightly unaware of the evidence.
That was to the best of my knowledge. My knowledge is now greater, and it appears that there is some evidence of a genetic component to intelligence. I appreciate having my ignorance fought on this subject.
I stand by what I said before, about the appropriate series of steps for science to follow in the rest of that post.
I think it’s MC1R that varies with our favorite populations and those who have some variants can be reliably predicted to have a higher IQ and be of one “race” than those with other variants and of another “race”.
Here’s the Wikipedia on SLC245. I doubt it’s the one because it wouldn’t explain the variation the way we like our IQ scores to rank.
Here’s the Wikipedia on OCA2.
That just can’t be it!
Here’s the Wikipedia on SLC45A2 http://en.wikipedia.org/wiki/SLC45A2
From the description it just doesn’t sound that good.
I know why they don’t work! The relationship probably exists as a function of the percent racist saturation in our society. I bet it was a much stronger relationship just 30 years ago! For people interested in the genetics of IQ to either get more fodder for their racism or to learn what real scientists do:
There’s a lot more interesting work than heritability studies out there. Here are links to a database that is collecting all the genetic variants with the best links to variation in IQ.
Anybody who says there is no evidence of genetic influence on intelligence is spouting politics. The real questions on the genetics of IQ relate to how the proteins of these genes act to influence intelligence, at least as judged by IQ.
I beg to differ, in countless past debates the “race realists” mention it many times and run with it. They continue to act like if no one has pointed before that the countless pages of research they quote does not show what they really need regarding the genetic differences in intelligence among races.
That is what I do notice in many of these discussions and why one has to be very specific, as I pointed before virtually all researchers point out that all humans have that capacity of inheriting intelligence. The “race realists” (not you BTW) pounce on anyone that simplifies it to be about all intelligence. But what I do see is that many of the “race realists” just expect that observation to carry the day for the rest of their misguided ideas that support their prejudice. It is not enough, as it is their reliance on researchers like Rushton and other Pioneer fund stooges that in reality failed to get traction where it counted.
Indeed–reading over what I wrote, it’s pretty obviously wrong. I’m not entirely sure what I was thinking when I wrote it, but I think I was trying to get at the idea that we’ve not found genes that control for intelligence. And I’ve even been corrected on that, I think.
The thing about twin studies is, they necessarily can’t do anything to prove differences between races, unless you can find some fraternal twins sets that:
a) have been adopted, and
b) have different racial ancestors.
One of those might be harder to find than the others.
So even though twin studies can inform us about intelligence, if folks want to posit a racial difference in intelligence, it’s difficult to imagine a path to doing so that doesn’t show up in a specific gene that controls for intelligence.
Folks positing a genetic explanation for differences in socially-constructed groups who lack such a step are racists, for the reasons I’ve explained above.
Well they identify likely targets by these various types of association studies. They all essentially identify genomic regions that vary with behavior. It’s better still if the findings are replicable because the pattern of associations can be quite different from study to study.
Data that can be interpreted as cause and effect may be developed from this genetic work or may come about as a result from other types of research. So the combined sets of data increases the confidence that one is studying a gene that controls intelligence.
Many of the 158 genes this author identified have been studied in knockout mice, where the gene is silenced in some way so that no protein is expressed because the gene cannot be meaningfully transcribed and translated into protein. The data from these studies can link the gene’s expression to various cognitive abnormalities. The author refers to these as experimentally verified but I am not 100% what is meant by that. There’s a book-learning way of saying experiment and a jargon way of saying experiment and I am not sure which is meant.
