Here's the promised thread looking at Harvard Geneticist David Reich's New York times editorial "How Genetics Is Changing Our Understanding of ‘Race’" in light of our story yesterday on polygenic scores for I.Q., a.k.a. DNA-based IQ test.
The Reich editorial argues that the racial categories we use actually align with real, observable, genetic difference between groups which, in turn, may be the source of real behavioral and COGNITIVE average differences between races.
Some people, reading between the lines, took this to mean that blacks are less than intelligent than whites or asians and genetics will prove it.
This thread asks whether such a proof is *technically* possible, given status of polygenic risk score tech.
This thread asks whether such a proof is *technically* possible, given status of polygenic risk score tech.
First, Lots of responses to Reich editorial. In Buzzfeed, @alondra and several others say Reich doesn't understand race. However, they chose to bypass Reich's discussion of intelligence entirely. buzzfeed.com/bfopinion/race…
In contrast, in @NYMag Andrew Sullivan, goes the opposite way, approving of Reich, immediately zeroing in on the race+I.Q. issue, checking in with @charlesmurray of The Bell Curve fame, etc.. nymag.com/daily/intellig…
Reich skates clear of saying races differ in intelligence, but intelligence IS the cognitive trait he's interested in, judging by his text. Like it or not, it's the one trait he gives over five paragraphs to. From the editorial: 
Same text with references added. These reports represent a series of newly successful gene hunts for the genetic determinants of I.Q. or of "educational attainment." This is new and cutting edge research Reich knows about.
We just published an article about how such gene discoveries can be turned into a score that predicts an indvidual's I.Q., from their DNA. Here's that story about DNA-based IQ tests. technologyreview.com/s/610339/dna-t…
(that maddening thing where Twitter disappears half your thread. Rest coming soon...)
Here's a previous thread that provides more details on polygenic scores for intelligence.
Currently, DNA assessments of an individual's IQ are questionable because they are not very accurate.
But pinpoint accuracy less important when looking at averages. What this tech really good for is looking at GROUPS, describing GROUPS, or dividing people into GROUPS (say, by IQ)
To me, Reich seems to be indicating that this same emergent technology, of modelling traits using polygenic scores, may eventually VERIFY that one group has, on average, higher polygenic scores for intelligence than another group.
Luckily, such a comparison is NOT POSSIBLE to do right now. First reason, as Reich notes, all the genetics data is from Europeans. No one has similar scope of data on other races.
Second reason, while you can kinda predict IQ from DNA in Europeans, data won't translate reliably to other ancestry groups or people of mixed heritage.
This is because the SNP "markers" associated w/ IQ can change positions relative to the causal genes depending on ancestry.
This is because the SNP "markers" associated w/ IQ can change positions relative to the causal genes depending on ancestry.
Here's a blog post which explains all this, using the "toy" example of a genetically predicted "tea consumption" ranking among British people when it is applied to French people. gcbias.org/2018/03/14/pol…
Thus, no one can effectively compare races by polygenic IQ score. I checked with scientists who I felt were likely to be interested in such a comparison, like @KirkegaardEmil , and they also explained it was not possible.
But...in the future it may be possible to use polygenic scores to assess and COMPARE ancestry groups at a genetic level in regards to intelligence and other cognitive traits. I think that will be qualify as a "forbidden" undertaking + for good reason. /END
