Fingering single genes

The ability to control in vivo gene expression may be a powerful tool in cancer therapy, gene therapy of inherited genetic diseases, and for the study of gene function. Small interfering RNAs are increasingly used in the study of the effects of gene knockout, but these molecules may be of limited therapeutic use in the clinical setting. In the September 22 PNAS, Siyuan Tan and colleagues at Sangamo BioSciences, Inc. report the successful use of an engineered zinc finger transcription factor to completely inhibit specific single gene expression in vivo, providing a model for the modulation of gene expression that would be of use in both therapeutic and research environments (PNAS, DOI:10.1073_pnas.2035056100, September 22, 2003).

Tan et al. built upon previous research that linked three two–zinc-finger domains in an engineered transcription factor to provide specific binding to a unique 18-bp region in the promoter of the checkpoint kinase...