KJ Muldoon, a 9-month-old baby from the US, became the first person treated with a personalized Crispr-Cas9 gene-editing therapy for CPS1 deficiency—a rare, life-threatening liver condition. Developed at Children’s Hospital of Philadelphia, the treatment corrected KJ’s unique genetic mutation using a custom-designed infusion. Previously reliant on strict diets and medication, KJ is now showing improved health. Doctors say this milestone could pave the way for personalized gene therapy for others with rare genetic diseases.
