Thread by @jayjoseph22

1/ Thoughts and comments about an interview with K. Paige Harden in the 9/12/2021 ed. of The Guardian. The interviewer is Zoë Corbyn. Harden is promoting her behavioral genetics (BG) field, and her book "The Genetic Lottery." UOS, all quotes from Harden.

theguardian.com/science/2021/s…

2/ "I wrote this book first for my fellow scientists, who haven’t necessarily seen the relevance of genetics for their own work or have been afraid to incorporate it because of these associations."

Nothing new. BG has been trying to convince "scientists" of this for decades.

3/ "There is a large body of scientific knowledge being ignored lest the eugenics genie be let out of the bottle."

Not true. BG claims and methods have been integrated into psychology and other behavioral fields for many years.

4/ "The core idea of eugenics is that there is a hierarchy of people who are inferior or superior that is rooted in biology and that inequalities are justified on that basis"

Not really. The "core of eugenics" is changing reproduction patterns among the "inferior or superior."

5/ "For a new person’s genetic sequence – [we] add up that information to produce...a polygenic score, that predicts how far they will go in school."

"Predict" = "correlation." Correlation ≠ cause.
Having two X chromosomes once "predicted" lower educational attainment (EA).

6/ "Crude though it is, the GWAS approach has found genetic variants that are correlated with going further in school."

False-alarm "genes for behavior" associations have been appearing for 50+ years. We should assume new claims are also false alarms, until proven otherwise.

7/"We see evidence that there’s a genetic influence on academic achievement in twin studies"

Untrue. Twin studies are based on the false assumption that identical and fraternal twins grow up experiencing "equal environments." BG interpretations of twin studies are simply wrong.

8/ "Scientists have identified more than 1,000 genetic variants spread over the entire genome, each of which has a tiny effect."

No evidence of cause. Correlation ≠ cause, and critics argue that polygenic scores (PS) are likely spurious correlations.

9/ "But it is still lower than the twin study estimate that about 40% of the variation in educational attainment is due to genes."

This refers to estimating heritability, another very controversial BG concept.

pzacad.pitzer.edu/~dmoore/public…

10/ BG heritability estimates are often derived from "biometric model fitting" techniques. Basic model fitting assumptions are found below. Does anyone think these assumptions are true? The model assumes the very thing it is attempting to prove. (From NL Segal, 2012).

11/ "We’re reasonably certain at this point that the causal genetic influence [in educational attainment] is not nil."

Not a sure-sounding statement. Despite numerous BG studies, Harden isn't completely certain that genetic influence on educational attainment (EA) "is not nil."

12/ "Polygenic score studies within families are now also suggesting genetic cause."

Links to polygenic score (PS) critiques:

sciencedirect.com/science/articl…

sciencedirect.com/science/articl…

proquest.com/openview/e16c5…

biorxiv.org/content/10.110…

sciencedirect.com/science/articl…

13/ Corbyn says: "Ruha Benjamin also suggested the hunt for more data to explain things just ends up being a barrier to acting on what we already know we need to do to fix the academic achievement gap…"

Ruha Benjamin @ruha9 is right. How did Harden respond?

14/ "I disagree that we already know what to do...Most of the things we try in education...make no difference to students’ lives"

U.S. spent $2-3 trillion in Afghanistan. Had even a fraction of that been spent on education, it would have made no "difference to students' lives"?

15/"Left" and "right" BG both supported by the field's crumbling pillars, all based on false assumptions: twin studies (reared together or reared apart), adoption studies, heritability estimates, polygenic scores, & model fitting.

Harden's book is based on these false pillars.

Example refuting Harden's claim that BG "knowledge" has been ignored in science up to now. In awarding Robert Plomin in 2017, the American Psychological Association recognized #behavioralgenetics as a "fully integrated mainstay of scientific psychology."

psycnet.apa.org/record/2017-57…

In "The Genetic Lottery" (which I have read), Paige Harden's defense of the validity of twin studies and their controversial underlying assumptions is weak, even though she leads the U. of Texas "Twin Project."
sites.la.utexas.edu/twinproject/th…

https://twitter.com/jayjoseph22/status/1436366380295540739?s=20