This May Be the Most Important Medical Story of the Decade

In just six months, a team at Children’s Hospital of Philadelphia and Penn Medicine designed a personalized therapy that could correct the single misspelled letter in KJ’s DNA using a gene editing technology known as CRISPR. To get the therapy inside KJ’s cells, doctors relied on the same kind of mRNA technology that powered the Covid-19 vaccines. He received his first dose at 6 months old. One year later, KJ is walking, talking and thriving at home with his family.