Efficiency assessment of the gene trap approach

Abstract

The trapping of genes in murine embryonic stem (ES) cells offers three features in one experimental approach: 1) analysis of the expression patterns of unknown genes by using a simple staining method, 2) rapid cloning of unknown genes, and 3) generation of mutant mouse lines. We performed a gene trap screen aimed at the discovery of new genes regulating embryonic development. We have processed 209 gene trap events for expression patterns in chimeric murine embryos. Randomly tested, β-galactosidase-positive ES cell clones resulted in vivo in 35% gene trap events showing no β- galactosidase activity, 39% gene trap events with ubiquitous β- galactosidase activity, and 26% gene trap events showi..