"Heritability" includes non-genetic factors, and combined with genetic factors accounts for ~50% of variation in intelligence.
For genetic factors alone, the consensus so far is that there is very weak correlation of genetic variation with intelligence, unless a not quite-yet-established polygenic score is constructed. To wit:
>From the 1990s until 2017 no replicable associations were found. GPS from these early GWAS, which we refer to as ‘IQ1’, predicted only 1% of the variance of intelligence in independent samples. It became clear that the problem was power: the largest effect sizes of associations between individual single nucleotide polymorphisms (SNPs) and intelligence were extremely small, accounting for less than 0.05% of the variance of intelligence.
However, things got "better":
>in 2016, a second meta-analytic GWAS analysis with a sample size of 294,000 identified 74 significant loci30. This analysis produced a GPS, EA2, that predicted 3% of the variance in years of education on average in independent samples30.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5985927/
It stretches the imagination how one would go from these numbers to claiming that "The best estimate of intelligence heritability in adulthood at the peak, using measurement-error-corrected estimates, is 70-80%.
For genetic factors alone, the consensus so far is that there is very weak correlation of genetic variation with intelligence, unless a not quite-yet-established polygenic score is constructed. To wit:
>From the 1990s until 2017 no replicable associations were found. GPS from these early GWAS, which we refer to as ‘IQ1’, predicted only 1% of the variance of intelligence in independent samples. It became clear that the problem was power: the largest effect sizes of associations between individual single nucleotide polymorphisms (SNPs) and intelligence were extremely small, accounting for less than 0.05% of the variance of intelligence.
However, things got "better":
>in 2016, a second meta-analytic GWAS analysis with a sample size of 294,000 identified 74 significant loci30. This analysis produced a GPS, EA2, that predicted 3% of the variance in years of education on average in independent samples30.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5985927/
It stretches the imagination how one would go from these numbers to claiming that "The best estimate of intelligence heritability in adulthood at the peak, using measurement-error-corrected estimates, is 70-80%.