Gene Targeting in Cultured Human Cells

The technique described in this chapter—gene targeting in cultured human cancer cells—brings a powerful tool to scientists studying the function of cell cycle control genes (1 ). This technology allows scientists to knock out genes in cultured human cells in an analogous fashion to the creation of knockout mice. This approach brings the power of genetics (the comparison of cells or organisms that are genetically identical except for a single, well-defined mutation) to the study of human genes in cultured human cells. Gene targeting is a particularly valuable approach for the study of cell cycle control genes because ectopic expression of these genes frequently results in cell cycle arrest or apoptosis. To date, several cell cycle control genes have been studied using human somatic-cell gene targeting, including p21^WAF1/CIP1 , p53, 14-3-3σ, and (ataxia-telangiectasia and Rad3 [ATR] ) (2 –5 ).