Some points:
the 23andme dataset is probably not as useful as you project. They are working from a fixed set of variants, not full genomes or even a complete set of SNPs known to vary. There are certainly many SNPs of interest that just aren’t in their data.
in projecting the gains from discovering further variants that affect intelligence, it’s not clear whether you’ve accounted for the low hanging fruit effect. With these statistical approaches, we obviously discover the variants of largest effect first. Adding millions of additional genomes or genotypes will allow us to resolve thousands of additional common variants, but they are going to be the ones that have really tiny effect sizes.
On the other hand (contradicting point 2 somewhat), quite a substantial fraction of variation in intelligence and other traits is likely due to the genetic load—rare mutations, some likely of substantial effect, all deleterious by definition. Identifying these and their effects is a thorny statistical problem due to their rarity, but if we can, they would actually be very promising edit targets. The advantage being the likely lack of negative side effects, and the fact that the top few for any person would likely be of large effect. Some of them are also probably wide-effect boosts, fixes to fundamental bits of cellular machinery! Downside is that this would be a custom targeting job per person.
The use of ’800 IQ’ is a little grating. The tests only go to 200 or 210 (and are not convincingly normed at that level). Still, fully superhuman, entirely outside the normal human trait range… I guess it’s a fair way to gesture at that.
our predictive models for IQ work significantly better for European or white populations because they were trained on that population. This implies that obtaining a bunch of data for Asian and African populations would allow us to identify additional targets. It surprises me that we don’t have some huge dataset from China, but at least we recently developed a 100K+ genotype of Han individuals, which should turn up some additional hits.
Overall, really promising direction. I appreciate the writeup on new and improved edit methods—I had not been following the field closely, and was unaware we had advanced this much on the previously state of the art CRISPR/Cas9.
I am not so sure about that. I am thinking back to the Minnesota Twin Study here, and the related fact that heritability of IQ increases with age (up until age 20, at least). Now, it might be that we’re just not great at measuring childhood IQ, or that childhood IQ and adult IQ are two subtly different things.
But it certainly looks as if there’s factors related to adult brain plasticity, motivation (curiosity, love of reading, something) that continue to affect IQ development at least until the age of 18.