Flying through the genome: a comprehensive study of functional genomics using RNAi in Drosophila.

Sequencing the DNA of an entire mammalian genome now seems routine. The human sequence along with the mouse--the model for mammalian genetics--and the rat--the model for mammalian physiology--are now part of the data archive. However, the real challenges for the 21st century are what to do with this information and how to test the function of so many different genes in so many different cellular contexts. The potential payoffs are enormous. Examples include a better understanding of disease pathologies with effective strategies for therapeutic interventions that cause few, if any, side effects.