Sagi and Kim used genome engineering to explore how lifespan could be enhanced in Caenorhabditis elegans. As expected, the individual overexpression of known C. elegans longevity-related genes increased lifespan. Importantly, this was also achieved by zebrafish transgenes that provide biochemical functions not found in C. elegans, such as an antibacterial lysozyme and a mitochondrial uncoupling protein. Combining up to four manipulations resulted in lifespan increases of up to 130%. The authors also characterized physiological features of long-lived strains, such as overexpression of superoxide dismutase 3 (SOD-3), as a possible rapid readout for longevity.