Your answer confuses me. Why so much if "rare variants turn out to be only a small portion of IQ"?
My lower bound is that mutational load contributes 10% of the variance in IQ. I call that small. Independently, I propose that there should be room for 50 standard deviations in improvement. Although it's not clear what more would even mean. Surely linearity would break down. What I mean by the possibility of "50 standard deviations" is 20 disjoint sets of changes, each of which would accomplish 2.5 standard deviations.
If the typical gene is deleterious and contributes 1/N of a standard deviation, then there is room for N standard deviations of i...
This thread is for asking any questions that might seem obvious, tangential, silly or what-have-you. Don't be shy, everyone has holes in their knowledge, though the fewer and the smaller we can make them, the better.
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