Oof. This is a toy model, and it has a serious problem with one of its assumptions:
> we can calculate that approximately 10,000 alleles control IQ
> Assume that the genotypes of parents 1 and 2 are completely independent, and that at each allele, the child has a 50/50 chance of inheriting each parent’s copy of that allele.
I’m not an expert, but I’m fairly confident that genetics don’t work like that. (IIRC they do in middle school, but they stop almost immediately in college…) Humans (mostly) have 26 pairs of chromosomes, and those chromosomes are full of bases, genes, alleles, etc. And they are not even close to independently inherited: gametes inherit long stretches of consecutive bases from a single parental chromosome. It’s a fascinating process and you can read about it here:
This has a large effect on the statistics of what one inherits from whom. I imagine it explains much of why people are likely to retain complex traits from their grandparents than one might expect, especially in cases where one or both parents are first-generation mixes of genetically rather distinct parents.
In any event, there are nowhere near 10k SNPs that can be independently inherited from a given pair of parents.
I have no particular comment on the overall model or conclusions of the OP, but it should at least acknowledge that its toy model is really quite implausible. (But I will note that my college class on genetics backed up its discussion of intrachromosomal recombination with math that was, if anything, even worse!)
> we can calculate that approximately 10,000 alleles control IQ
> Assume that the genotypes of parents 1 and 2 are completely independent, and that at each allele, the child has a 50/50 chance of inheriting each parent’s copy of that allele.
I’m not an expert, but I’m fairly confident that genetics don’t work like that. (IIRC they do in middle school, but they stop almost immediately in college…) Humans (mostly) have 26 pairs of chromosomes, and those chromosomes are full of bases, genes, alleles, etc. And they are not even close to independently inherited: gametes inherit long stretches of consecutive bases from a single parental chromosome. It’s a fascinating process and you can read about it here:
https://en.m.wikipedia.org/wiki/Genetic_recombination
https://en.m.wikipedia.org/wiki/Chromosomal_crossover
This has a large effect on the statistics of what one inherits from whom. I imagine it explains much of why people are likely to retain complex traits from their grandparents than one might expect, especially in cases where one or both parents are first-generation mixes of genetically rather distinct parents.
In any event, there are nowhere near 10k SNPs that can be independently inherited from a given pair of parents.
I have no particular comment on the overall model or conclusions of the OP, but it should at least acknowledge that its toy model is really quite implausible. (But I will note that my college class on genetics backed up its discussion of intrachromosomal recombination with math that was, if anything, even worse!)