I have a new column this week on OnlySky. It’s about the future of genetic medicine – which, after decades of promise, has finally arrived.
CRISPR technology gives us the power to edit the DNA inside a living cell. We’re already using it to cure some inherited disorders, like sickle-cell anemia. But those are inherently easier to treat, since we can harvest stem cells from a person’s body, do the genetic edit in the controlled environment of a lab, and make sure that everything is working as intended before we transfuse them back.
The holy grail of genetic therapy is the ability to modify DNA within the body, known as in vivo gene editing. In a new paper published this month, a team of scientists claims to have done just that. With this technique, they appear to have saved the life of a baby born with a rare and deadly genetic disease. More studies are still needed, as is always the case in science; but if this result holds up, it’s certain that more cures for previously untreatable conditions are soon to follow.
Read the excerpt below, then click through to see the full piece. This column is free to read, but paid members of OnlySky get some extra perks, like a subscriber-only newsletter:
Time was short, and with KJ facing brain and organ damage, his parents and doctors decided to try an experimental treatment rather than waiting for a transplant. The doctors sequenced his genome to determine the exact mutation he had, then designed a personalized base-editing therapy. Rather than using a virus to carry the gene editor, which can provoke a harmful inflammatory response, they encapsulated it in lipid nanoparticles that are taken up by cells and release their contents into the interior.
They engineered human cell lines in a petri dish to carry the same mutation, and dosed them with the gene editor to prove that it altered the DNA as intended. They tested it on mice and monkeys for safety and efficacy. Then, in February 2025, when KJ was six months old, they infused the gene editor into his body—and held their breath.





