I would say it has already been confirmed. There have been three studies now using genes to predict educational attainment (easier to measure in large data than IQ, but very similar, as it turns out). We can now predict about 10% of the variation in educational attainment from your genes. This might not sound a lot, but if you look at the difference between the top and the bottom genetic scores, it is substantial. (Like, top quintile: 50% go to college, bottom quintile, 10% go to college.)
These are not just correlations. By looking within families, we get an unbiased estimate of the true causal effects of these genetic variants (because DNA is randomly assigned among siblings by the "lottery of meiosis"). Effect sizes are smaller than if we look across different families, but still significant and large.
Lee, J.J., Wedow, R., Okbay, A., Kong, E., Maghzian, O., Zacher, M., Nguyen-Viet, T.A., Bowers, P., Sidorenko, J., Linnér, R.K. and Fontana, M.A., 2018. Gene discovery and polygenic prediction from a genome-wide association study of educational attainment in 1.1 million individuals. Nature genetics, 50(8), p.1112.
That cite is already outdated! The EDU SOTA is now 16%: "Genomic prediction of cognitive traits in childhood and adolescence" https://www.biorxiv.org/content/early/2018/09/17/418210 , Allegrini et al 2018. (It uses some tricks to boost the statistical power of Lee et al 2018 - GWASes in general waste a lot of predictive power by not using multiple traits, realistic priors etc. So it's easy to do better.)
These are not just correlations. By looking within families, we get an unbiased estimate of the true causal effects of these genetic variants (because DNA is randomly assigned among siblings by the "lottery of meiosis"). Effect sizes are smaller than if we look across different families, but still significant and large.
Lee, J.J., Wedow, R., Okbay, A., Kong, E., Maghzian, O., Zacher, M., Nguyen-Viet, T.A., Bowers, P., Sidorenko, J., Linnér, R.K. and Fontana, M.A., 2018. Gene discovery and polygenic prediction from a genome-wide association study of educational attainment in 1.1 million individuals. Nature genetics, 50(8), p.1112.