With the majority of human genes in hand and the focus now on discerning the function of these genes, competition is growing in the functional genomics arena. An example is the increasingly crowded knockout mouse market, as illustrated by last week's partnership between Exelixis Inc., Artemis Pharmaceuticals GmbH and Sangamo BioSciences Inc. to combine their technologies in order to develop a new and faster method for producing conditional knockouts.

As opposed to knockouts in which a gene is constitutively turned off, conditional knockouts allow researchers to assess the effects of silencing a given gene at various stages of development or disease progression. Also, the ability to turn a gene off and back on can serve to mimic the action of a drug.