Genetic screens in haploid ES cells

Recently established haploid mouse embryonic stem cells (ESCs) enable us to screen for recessive genes easily and are expected to be a powerful tool in the area of forward genetics. In this study, using N-ethyl-N-nitrosourea (ENU) mutagenesis in haploid ES cells, we performed a genome-wide screen for genes involved in glycosylphosphatidylinositol-anchor (GPI-anchor) biosynthesis.