Gene Trap: Knockout on the Fast Lane

  • Melanie Ullrich
  • Kai Schuh
Part of the Methods in Molecular Biology book series (MIMB, volume 561)


Gene trapping is a powerful tool to ablate gene function and to analyze in vivo promoter activity of the trapped gene in parallel. The gene trap strategy is not as commonly used as the conventional gene-targeting strategy, although it offers appealing options. Nowadays, a wide collection of embryonic stem cell clones, with a huge variety of trapped genes, have been identified and are available through the members of the International Gene Trap Consortium (IGTC). This chapter focuses on BLAST searches for the appropriate stem cell clones, the confirmation of vector insertion by RT-PCR or X-Gal staining, and the characterization of the exact insertion site to develop a PCR-based genotyping strategy. Furthermore, protocols to follow the activity of the commonly used β-galactosidase reporter are given.

Key words

Gene trap Gene disruption Promoter activity Embryonic stem cells Mouse genome β-Galactosidase β-Geo X-gal staining 



The authors would like to thank Tobias Fischer and Peter M. Benz for providing organs of mice with different genes trapped to demonstrate X-Gal stainings, and Karin Bundschu for providing X-Gal stained tissue sections of mice with a trapped spred2 gene.


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Copyright information

© Humana Press, a part of Springer Science+Business Media, LLC 2009

Authors and Affiliations

  1. 1.Institute of Physiology IUniversity of WuerzburgWuerzburgGermany

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