World’s First Baby Treated with Personalized CRISPR Gene Editing
June 02, 2025
A baby boy suffering from a rare genetic disorder is showing promising signs of recovery after becoming the first known patient to receive a personalized CRISPR gene-editing treatment tailored specifically to his unique mutation. Nearly ten months old, KJ Muldoon has undergone three doses of this groundbreaking therapy, aimed at fixing a genetic error that affected his body’s ability to process protein, his parents shared with reporters.
Despite this progress, doctors caution that it’s too early to call the treatment a cure. Rebecca Ahrens-Nicklas, a pediatrician at the Children’s Hospital of Philadelphia and one of KJ’s physicians, emphasizes the early stage of this approach, noting, “We still have much to learn from him.”
The therapy’s rapid development is a remarkable feat: an international team of clinicians and researchers from academia and industry, supported by U.S. government agencies, designed the treatment in just six months. However, because the drug is custom-built to match KJ’s specific genetic profile, it is unlikely to be used for any other patient, Ahrens-Nicklas explains.
This personalized gene-editing strategy represents a bold new direction in treating ultra-rare genetic diseases. Arkasubhra Ghosh, a gene therapy expert from Narayana Nethralaya Eye Hospital in India, who was not involved in the study, describes it as “the future for gene and cell therapies,” expressing excitement about the potential of CRISPR to transform treatment for rare conditions worldwide.
CREDITS: SCIENTIFIC AMERICAN