Synchronization by bleaching does not affect longevity

C. elegans has been used extensively for research on the biology of aging due to its genetic tractability and short lifespan. In order to measure lifespan, populations of worms are synchronized so that all of the worms being measured begin the assay at the same age. This is typically accomplished by simply picking worms of a particular developmental stage to start the lifespan experiment or through bleaching, a process through which the body of the worm is dissolved in a solution of bleach (sodium hypochlorite) and sodium hydroxide to release its fertilized eggs. In this experiment, we examined the effect of bleaching on lifespan in wild-type worms and the long-lived mitochondrial mutant isp-1 . We found that bleaching did not affect the longevity of wild-type worms or isp-1 mutants. While we cannot exclude the possibility that bleaching affects the lifespan of specific genetic mutants, our results indicate that wild-type longevity is unaffected and that for at least some genetic mutants bleaching can be used for synchronization prior to initiating a lifespan experiment.