D4 and C2 assessed for chimerism and germline transmission. Mus musculus

Two independent ES cell lines (D4 and C2) were assessed for chimerism and germline transmission. Although these lines were able to produce chimerism at early passage, no germ line transmission was seen. After passaging in a proprietary medium and subcloning by detaching loosely connected cells and culturing in the recommended medium, both lines experienced an increase in potential as evidenced by an enhanced ability to go germ line. Analysis of early passage, and late passage detached and attached cells will allow the determination of genes that may be implicated in the increase of potential seen in these cells. Note: additional replicates may be added at a later date. Keywords: embryonic stem cells, chimerism, germline transmission Overall design: this experiment include 6 samples and 34 replicates