Straight talk about epigenetics and intergenerational trauma

Razib Khan in Unsupervised Learning:

In the last decade, sweeping mainstream-media claims about epigenetics’ expansive role in shaping our world have become hard to escape. I am a geneticist and happy to stipulate that epigenetics is responsible for a considerable amount of our planet’s dazzling biological complexity. And yet when someone comes at me with explanations of anything social and behavioral in humans predicated on epigenetic effects, I cringe like an astronomer informed that planetary dynamics determine my personal character (typical Capricorn hubris they might say). The details of your star chart might be precisely correct, yet I don’t have to tell you that no astronomer seriously ascribes comparable validity to astrology and astronomy. Epigenetics is a powerful and ubiquitous process in biology but entails no mechanism equipped to explain any of the multi-generational psychological phenomena it’s called upon to legitimize in media coverage, claims about which are both reliably overblown and entirely speculative. Let’s inventory epigenetics’ actual reach and influence; you can arrive at your own conclusions about whether it is plausibly, as headlines often claim, the transmission mechanism for such phenomena in humans as “intergenerational trauma.”

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