Gene editor may have cured infant of a deadly metabolic disorder

A little-known gene editor, tested with help from a disgraced gene therapist seeking redemption, may have cured a 1-year-old boy of a deadly metabolic disorder. Announced last week by a company developing the therapy, the result could be the first success at stitching a curative gene into a “safe harbor,” a specific chromosomal location where its integration is unlikely to disrupt existing DNA in a way that triggers cancer or other problems. Because the gene should now be integrated in the baby’s genome, in this case within cells of the boy’s liver, it should persist as the organ—and person—grows.

The gene editor, dubbed ARCUS, is a DNA-cutting enzyme known as a nuclease, It is in some ways simpler and potentially better than the more famous CRISPR platform and could also help treat other genetic metabolic disorders. The company, iECURE, will not present data for the treated infant until March. But the apparent success of the safe harbor approach with the editor in the very first patient who received it is especially significant for iECURE co-founder James Wilson, who helped develop...