In 1933, the Third Reich passed the Law for the Prevention of Offspring with Hereditary Diseases—a chilling attempt to control who was allowed to be born, rooted in pseudo-scientific notions of “racial purity” and Aryan superiority. Nazi medical schools taught students to worship genetic “perfection,” and had the tools of today’s genetic science existed then, it’s not hard to imagine how ruthlessly they would have deployed them. The Third Reich’s obsession with genetic purity laid the groundwork for the Holocaust. The specter of eugenics haunts every new advance in reproductive technology, and today, that ghost is stirring again.

Last week, a coalition of leading scientific organizations—including the International Society for Cell and Gene Therapy—called for a 10-year global moratorium on human genetic editing. Their message is clear: the science is moving faster than our understanding of its risks, and the ethical questions it raises are more urgent than ever.

The immediate spark for this renewed debate is a new software platform from Nucleus Genomics, a company founded by 25-year-old Kian Sadeghi, and backed by tech luminaries like Peter Thiel and Alexis Ohanian. What they have created sounds like the premise of a near-future sci-fi thriller: prospective parents, sitting with a dashboard of up to 20 potential embryos, ranking them based on over 900 traits. These include medical risks—like Alzheimer’s, cystic fibrosis, schizophrenia—but also non-medical characteristics such as eye color, predicted height, BMI, and yes, even markers associated with IQ.

They aren’t just choosing health—they’re choosing a child’s future identity.

Nucleus calls it “genetic optimization.” Critics call it something else: consumer driven eugenics.

What sets this apart from the preimplantation genetic screening already used to avoid serious heritable diseases is the scale, ambition, and philosophical shift: from preventing harm to engineering superiority. Newsweek reports that early users are sorting embryos based on polygenic scores for intelligence and mental illness—sliding ever closer to a world in which undesired traits are quietly discarded before birth by those able to afford the technology.

Even the voluntary pursuit of perfection, especially when fueled by inequality and tech utopianism, raises serious ethical questions. Who decides what traits are “desirable”? And who besides those capable of paying for it get access to this technology?

Dr. Arthur Caplan, head of the Division of Medical Ethics at NYU, has been warning for decades about what happens when genetic knowledge meets market forces and parental ambition. In recent comments, he emphasized that genes aren’t destiny. Even identical twins with the same DNA often live radically different lives based on upbringing, environment, or sheer chance.

And there are societal consequences of letting wealthy, well-informed parents create genetically curated offspring while poorer families are left behind. One tech investor’s “optimized child” could be another parent’s “genetic underclass.” We risk creating a society where privilege is literally written into our DNA—a new kind of hereditary elite.

Some in the longevity movement—where Sadeghi and his investors have ideological roots—frame this as empowering. They see a world where humans engineer themselves out of disease, decline, even death. But that vision requires a brutal calculus: decide who gets born, and who doesn’t.

As Liz Wolfe at Reason wrote, “This isn’t about Baby Mozart anymore. It’s about a world where parental choice intersects with Silicon Valley hubris and deeply personal ethics.”

Some ethicists fear a coming homogeneity—a world where parents converge around the same desirable traits, slowly narrowing the spectrum of human diversity. NYU’s Caplan said this could undermine human resilience at the species level. And the “solution” from some defenders is both chilling and telling: store vast numbers of frozen embryos with diverse traits, in case we need them later.

That’s not empowerment. That’s speculative breeding.

What’s most unsettling is the regulatory void. Despite the profound moral, social, and biological stakes, the U.S. has no coherent policy or laws on polygenic screening or embryo optimization. As with many types of technology, including AI, the advances come at breakneck speed, faster than society’s ability to regulate and to institute safety guidelines.

That leaves the terrain wide open for ambitious startups and their investors to set the rules themselves.

Dr. Bruce Levine, a professor of cancer gene therapy at the University of Pennsylvania, has been blunt: “Germline editing has very serious safety concerns that could have irreversible consequences. We simply lack the tools to make it safe now and for at least the next 10 years.”

So, is this science fiction? Or is it our future?

The more urgent question might be this: Whose future is it?

Because once you start choosing which embryos get born based on traits, the line between medicine and ideology vanishes. And history has already shown us how dangerous that can be.

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