The Laboratory of Unintended Consequences
When researchers at Oregon Health & Science University opened the incubators containing rhesus monkey embryos in 2018, they were searching for ghosts. Not the spectral kind, but the genomic sort: unintended mutations, errant cuts, the molecular scars that might suggest CRISPR-Cas9 — the decade's most celebrated genetic tool — was less precise than its boosters claimed. The monkeys, when born, carried none. Their genomes showed no evidence of off-target edits, no collateral damage from the molecular scissors that had rewritten their DNA in utero . It was a rare piece of unambiguous good news in a field increasingly defined by its moral and technical complexities.