Probably not? The effect sizes of the variants in question are tiny, which is probably why their intelligence-promoting alleles aren’t already at fixation.
There probably are loads of large effect size variants which affect intelligence, but they’re almost all at fixation for the intelligence-promoting allele due to strong negative selection. (One example of a rare intelligence promoting mutation is CORD7, which also causes blindness).
Since posting this two years ago, I believe Kman looked into this more and concluded that the intelligence enhancement effect of CORD7 is likely not real.
More information: that “CORD7” variant is actually in an IQ GWAS, but showed ~0 effect. Note that I couldn’t rule out the PROM1 variant in the same way since it’s much rarer and not in the GWAS.
I think it suggests that the blindness comes from a different, rarer variant (in the PROM1 gene). If anything that would update me towards thinking the IQ effect, if real, also comes from that rarer variant.
(Edit: the 6 carriers of the PROM1 mutation studied in this paper had an average verbal IQ of 104, which is pretty strong evidence against it giving a huge boost to verbal IQ as reported by the CORD7 paper).
Probably not? The effect sizes of the variants in question are tiny, which is probably why their intelligence-promoting alleles aren’t already at fixation.
There probably are loads of large effect size variants which affect intelligence, but they’re almost all at fixation for the intelligence-promoting allele due to strong negative selection. (One example of a rare intelligence promoting mutation is CORD7, which also causes blindness).
This suggests that the intelligence enhancement and the blindness come from different independent alleles.
Since posting this two years ago, I believe Kman looked into this more and concluded that the intelligence enhancement effect of CORD7 is likely not real.
More information: that “CORD7” variant is actually in an IQ GWAS, but showed ~0 effect. Note that I couldn’t rule out the PROM1 variant in the same way since it’s much rarer and not in the GWAS.
What’s your take on this?
I think it suggests that the blindness comes from a different, rarer variant (in the PROM1 gene). If anything that would update me towards thinking the IQ effect, if real, also comes from that rarer variant.
(Edit: the 6 carriers of the PROM1 mutation studied in this paper had an average verbal IQ of 104, which is pretty strong evidence against it giving a huge boost to verbal IQ as reported by the CORD7 paper).