How do "genes" work? So-called experts have a hard time agreeing
How we talk about genes shows many are confused. Seductive stats illusions, iffy gene ideas, bad causology, and lax jargon, are creating a recipe for epistemic comedy (and genetic tragedy).
Jag Bhalla is an entrepreneur, inventor and writer. His current project is Errors We Live By, a series of short exoteric essays exposing errors in the big ideas running our lives, details at www.errorsweliveby.com. His last book was I'm Not Hanging Noodles On Your Ears, a surreptitious science gift book from National Geographic Books, details at www.hangingnoodles.com. That explains his twitter handle @hangingnoodles.
1. Do you know how genes work, or grasp what gene stats mean? A recurring IQ-and-genes fuss shows many are tempted into an epistemic comedy by seductive stats illusions, bad causology, and lax jargon.
2. IQ is 40-80% heritable and interracial IQ differences are “substantial [enough to]... affect… economic outcomes,” writes Andrew Sullivan, wielding science “bravely” alongside Sam Harris and Charles Murray.
3. Sullivan takes the data to mean individual IQ is 40-80% “caused by” genes. That’s not true, nor coherently knowable. Race-focused responses, like Ezra Klein’s, don’t explain the bonkers stats errors.
4. Technical heritability analyzes group variation stats not individual trait level factors. Stats professor Cosma Shalizi explains heritability “says nothing about how much [a trait’s level]… is under genetic control” and it’s “irrelevant to malleability” (heritable ≠ immutable; genes often aren’t carved-in-stone fate).
5. Exposing stats illusions Shalizi warns “causal-sounding phrases... encourage confusion” in many analyses of variance studies (where "due to," "explained by," "account for" don’t have ordinary meanings).
6. A not-known-enough thought experiment illustrates gene-nurture inseparability and misattribution risks—if society sent redheaded kids to bad schools, ginger genes would correlate with (seemingly “predict”) low IQ.
7. Many phenomena don’t fit the specific causal structure that basic stats presume—independent factors with additive effects. Most biological traits involve many, many gene-products playing hyper-complex, interdependent, non-additive roles via long intricate processes.
8. Statistically decomposing processes or functional systems is often like asking what percent of a car’s speed is caused by its engine or fuel or driver (all contribute inseparably).
10. Still, the “joy of stats” seduces many into confusion and causal overreach. For instance, Antonio Regalado covering dodgy DNA-to-IQ “predictors” uses “linked to” and “tied to” but slips into over-causal “explains” and “genetic determinants.”
11. Presumptive causality strains the statistical sense of sexy “polygenic scoring” methods, whose fans hope “predictions can operate in complete ignorance of the biological basis.” This data-fueled folly ignores “ginger-gene” complications.
12. Clearer-eyed experts offer cavernous caveats—neither heritability nor polygenic scoring illuminate genetic “causes” (Turkheimer), “summing” variant contributions isn’t wise (Racimo), and interpretation complexities abound (Novembre).
13. Lax causology and imprudent presumptive causality pervade genomics, “precision” medicine, Big Data and AI. The complete-ignorance-of-how fans forget that including non-causal factors skews, if not ruins, allocation-of-variation calculations (see “structured noise”).
14. Tread gingerly and always consider the causology. Are putative factors direct (“proximate”) causes, or many-complicated-steps removed? Is causal stability warranted? Or causal completeness? Does the causal structure fit stats tools? Do mixed response types muddy your metrics?
16. Gene stats jargon has misled Sullivan (scientists like Harris and Murray have less excuse)—the “economic outcomes” leap gets the science, stats, and logic wrong (see Chris Dillow, Matthew Yglesias).
- The minimum wage debate rages on
- The same study authors in 2017 famously argued that raising the wage to $15/hr. in Seattle and Tacoma actually cost jobs
- This study says something else, though study authors are quick to say they don't necessarily contradict each other. Ummm ...
Calling all big thinkers!
The 72-page report makes a case against modern policy proposals like "Medicare for All" and free college tuition.
- The report comes from the White House Council of Economic Advisers (CEA), which is run by professional economists.
- It attempts to make direct connections between modern-day progressives and past socialist figures like Stalin and Mao.
- The report comes in the wake of other explicitly anti-socialist sentiments expressed by the Trump administration.
SMARTER FASTER trademarks owned by The Big Think, Inc. All rights reserved.