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Possibilities of interest in gene-editing for increased intelligence

There’s been some discussion around Charles Murray’s recent claim that a lot of people would probably try to make their kids smarter with gene editing if it were reasonably cheap. There’s been some foolish points, some reasonable ones, but not many with much imagination. So I thought I’d point out some possibilities. Hat tip to this old discussion between Jerry Pournelle and Greg Cochran for inspiration and some ideas.

Suppose, as a basis for discussion, someone somewhere tries to edit genes of gametes or embryos to improve the child’s eventual intelligence. What might happen?

  • It’s hard to change lots of locations, so edits get done on the highest-effect loci. One or more of them turn out to have heterozygote advantage but nasty recessive effects. People would probably be smart enough not to give the kids torsion dystonia or Tay-Sachs, but we might see brand new exciting Mendelian disorders, and kids with six different ones simultaneously.
  • Off-target effects from the gene editing are reasonably common. Embyro screening catches most of the problematic ones, but not large chromosomal rearrangements that leave things intact. Balanced translocations where the genes are all there, but you might have a chromosome arm hop to another chromosome. The edited kids are fine. Their children all have things like inherited Downs or Kleinfelters.
    • Rapid adoption of the technology means most children in a generation have been gene edited. 25 years in, we find out almost all of the Changed are infertile or have extremely disabled children. Lots of possibilities: population crashes, mass adoption of Unchanged children, etc. Maybe one company was smart enough to screen for structural variants and that subpopulation takes over the world.
  • We weren’t quite looking for what we thought we were. We sort of get increased intelligence, but with something else riding along.
    • We use polygenic risk scores for educational attainment for editing, end up getting kids with higher conscientiousness and conformism, losing our population of irascible old assholes.
    • We use childhood IQ, get much more rapid childhood development.
    • We use adult IQ, get much slower childhood development, with 25 year olds still in middle school.
  • There’s side effects we weren’t expecting.
    • Bigger heads: more troubles in birth, higher C-section rate. 5 year olds with neck braces to help their neck muscles hold up their heads.
    • Shifts in common personality types: conscientiousness, extraversion. The funny kind of strangeness you see in mathematicians.
    • Ideological changes. The smart kids are wild radicals, pushing society into a new form every five years, or staid conservatives, enforcing complete rigidity on everyone.
    • Funny shifts in components of intelligence. Maybe we see big increases in mathematical intelligence or verbal intelligence but not vice versa.
  • The smart kids get alienated from everyone else, including their families. Parents stop doing it, and we get a long term schism in society between the Changed and the Unchanged.
  • The polygenic risk score we use works better in some populations than others. One group gets much much smarter, the other doesn’t move much. Social unrest and division ensue.
  • It’s expensive, so expensive that it’s inaccessible to most people. The rich and powerful make their kids smart. Dynastic politics ensue. They ban the technology for the peasants to avoid competition. Dynasties stay much more stable because there’s no longer any regression to the mean.
  • First-rate powers are risk averse and ban it. A third rate power decides to roll the dice and Indonesia or Uganda or Ecuador becomes the new power center of the world.
  • There’s incompatible sets of edits that can’t be made on the same genome.
    • Different sets of gene edits push you in different directions: you can make your kid wildly creative or a brilliant mathematician but not both.
    • Companies deliberately or accidentally engineer gene edits to be incompatible. Maybe Google merges two chromosomes so that their edits can only breed with other Google-compatible edits. We speciate into multiple similar but genetically incompatible species based on which company did your grandpa’s gene editing.

Just a morning’s thoughts. Any other ideas?

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  1. I like the method proposed by Robert Heinlein in the book: Beyond This Horizon. Instead of modifying existing genes using something like Crispr, examine the genetics of a bunch of eggs and sperm combinations (maybe based on a neural network created by some massive Genome-wide association study). Then pick the sperm/egg combination that will give you the “best” overall characteristics of the new baby. This way you are only selecting from gene combinations that could have arisen naturally and have less chance for crazy bad gene combinations that you didn’t foresee.


  2. This is already standard practice for those who for one reason or another use IVF to establish a successful (viable) pregnancy. My wife and I used IVF for our 3rd child, due to my having a low count. As I recall, they removed and fertilized ~22 eggs, though only about half actually took. We were given the option (additional $4-8G) to have preimplantation genetic screening (PGS) on the 10-12 embryos, which we did. As I recall, PGS screens for a number of chromosomal abnormalities, which turned out to be helpful being that all but two embryos came back with abnormal, though w/o any discernible pattern. My wife and I elected to have our own genetic screening which turned out completely normal as well. In any case, we ended up with a perfectly healthy little girl (3 yrs old now) and one additional embryo in the freezer (which I’m currently trying to convince my wife to implant).

    Having said all that, while the company that did our PGS did not and would not (I asked) provide information save chromosomal abnormalities. If given the opportunity, I would’ve absolutely utilized information regarding cognitive or behavioral traits. The blunt truth is, there is nothing in this world more valuable than intelligence, and all else being equal, I would rather my child have more of it than not. What’s more, anyone who says otherwise or feigns indifference is being less than honest. When I encounter such people, I’m always interested to know two things:
    (1) Since intelligence is of no particular import to them, then I would think it safe to assume they wouldn’t take exception to someone calling them an idiot.
    (2) Since intelligence is of no particular import to them, then I would think it safe to assume, if given the choice, they’d be just as likely to prefer their newborn child to have an IQ of 70 as they would 130.

    Strangely, I’ve yet to meet anyone who says they’d be just as likely to chose for their child an IQ of 70…


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