“If PRS gives you the power to reduce your offspring’s lifetime risk of type 2 diabetes from 30% to 27%, is that worth the time, money, and emotional investment?” asks bioethicist Hank Greely of Stanford University in California. “And to whom?” That’s very different, he says, from the confidence with which single-gene diseases can be screened and avoided.

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It’s not clear that screening for such non-disease traits would work anyway. “I think the things that parents are most interested in, like intelligence, sports and musical ability, will have extremely small to nonexistent convincing PRS results,” says Greely. A study in 2019 suggested that using polygenic screening to select embryos for height and IQ would be likely to make only a tiny difference on average – and there’s a fair chance you wouldn’t end up picking the “best” embryo.

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“We urgently need public and policy conversations about polygenic embryo screening,” says Hasson. Finding the right balance between autonomy and social responsibility is the fundamental dilemma of liberal democracies. “We let people spend their money, and make decisions powerfully affecting their kids, on far more clearly bogus information than PRS,” says Greely.