Vries, L. de, Weijer, M. van de, Pelt, D., Ligthart, L., Willemsen, G., Boomsma, D., Geus, E. de, & Bartels, M. (2021). Individual differences in the effect of the COVID-19 pandemic on optimism and meaning in life. PsyArXiv. https://doi.org/10.31234/osf.io/b2ge6

I'm saying there are no disorders, there are just quantitative dimensions.

https://hwcdn.libsyn.com/p/0/e/4/0e4bbca6693b2a86/Making_Sense_211_Plomin2028Paywall29.mp3?c_id=78559928&cs_id=78559928&expiration=1596420276&hwt=19fd0a656a4c689d6ee9275abb18efba#t=4248,4271

the most important thing we've learned from the dna revolution in the last 10 years is that genetic influences on complex traits are due to thousands of tiny dna differences

https://hwcdn.libsyn.com/p/0/e/4/0e4bbca6693b2a86/Making_Sense_211_Plomin2028Paywall29.mp3?c_id=78559928&cs_id=78559928&expiration=1596420612&hwt=4931be7ad51a8b694ee914f2a57f0a35#t=3532,3720

these polygenic scores are perfectly normally distributed

https://hwcdn.libsyn.com/p/0/e/4/0e4bbca6693b2a86/Making_Sense_211_Plomin2028Paywall29.mp3?c_id=78559928&cs_id=78559928&expiration=1596420486&hwt=7d85d388fc28c224973bc78d6860e63b#t=4015,4086

This does suggest some of the supposed heritability is actually prenatal environment (or some other analogous factor). It's also possible that e.g. mitochondrial DNA plays a bigger role than previously recognized, much how thyroid status is the #1 predictor of mental retardation. Perhaps IVF will shed further light on the issue.