If humans are ever going to be able to regrow damaged tissues the way lizards and fish routinely do, it will require the precise control of gene expression in time and place — otherwise you might end up with random cells growing everywhere or a new body part that never quits growing. That is, stopping the process just as important as starting it.

A team of Duke scientists studying how other animals regrow damaged tissues has made an important step toward controlling at least one part of the regenerative machinery with that kind of precision. They used the mechanisms zebrafish rely on to repair damage to their hearts combined with viral vectors used for gene therapy in humans.