Columbia Embryo-Editing Study Pulls Nucleus Genomics Into the Ethics Fight

Why it matters

The claim moves Nucleus Genomics from consumer-facing genomics into a far more sensitive debate: whether embryo editing can be made technically reliable, ethically defensible, and legally usable.

Kian Sadeghi (@KianSadeghi5) said in a post on X that Nucleus Genomics (@nucleusgenomics) and Columbia University (@Columbia) have announced high-efficiency editing of human embryos, a claim he framed as a world first.

The underlying work, according to a New York Times story linked by Sadeghi, was led by Columbia geneticist Dieter Egli and used base editing, a newer gene-editing method that changes individual DNA letters without making the larger cuts associated with older CRISPR approaches. The study has been posted online and is under journal review.

Egli's group targeted two genes in donated fertilized eggs and two-cell embryos: PCSK9, which can carry mutations that raise LDL cholesterol and heart-disease risk, and HBG, which helps direct fetal hemoglobin production. The researchers reported successful edits to each gene, and in some cases to both genes in the same embryo, without the extensive chromosome damage Egli's lab previously saw in CRISPR embryo experiments.

The result is still far from a clinical product. The Times reported that some embryos became mosaics, with some cells carrying the edit and others retaining the original gene sequence. Egli also cautioned that the work leaves unresolved questions about harmful side effects. "We're not saying this is going to be used tomorrow in the clinics," he said.

For Nucleus Genomics, the embryo-screening startup, the study moves the company closer to one of biotechnology's most sensitive frontiers. The Times identified Nathan Treff, the company's chief clinical officer, as a co-author. Treff said the ability to fix disease-causing mutations in embryos could eventually help IVF patients implant embryos that otherwise would have been discarded, while acknowledging more work is needed.

Nucleus Genomics will support the next stage of Egli's research, according to the Times. That matters because the federal government does not fund human-embryo research, and because the company already operates in a contested market: it screens IVF embryos for thousands of genetic disorders, predicts risks for conditions such as heart disease and diabetes, and analyzes genes linked to traits including height and intelligence.

That positioning has drawn scrutiny. The Times noted that Nucleus Genomics' New York subway ads urging parents to "have your best baby" stirred criticism from geneticists who argue that some trait predictions, including IQ, have low accuracy. Critics have also accused the company of promoting a biotech version of eugenics, a charge the company rejects.

Outside researchers were split between technical interest and ethical alarm. Paula Amato, a fertility expert at Oregon Health & Science University, called the method "promising" but said the final journal publication will matter. Ana Iltis, a Wake Forest University bioethicist, warned that some harms may not appear until after birth. Fyodor Urnov, a UC Berkeley geneticist, argued that conventional IVF embryo screening is safer than attempting embryo editing, and warned that the work could give "baby improvers" a technical path into ethically fraught territory.