Researchers at the Arc Institute developed and optimized bridge recombinase technology for human cells, allowing programmable megabase-scale chromosomal DNA rearrangements. This RNA-guided system enables insertion, deletion, and inversion of large genomic regions up to a million base pairs, surpassing traditional precision editing limited to small nucleotide changes. The platform holds promise for creating versatile gene therapies with broad applications in complex genetic diseases. The work, published in Science, validates the potential of bridge recombinases as next-generation genome engineering tools.