To create a mouse to test the information theory, we inserted I-PpoI into a circular DNA molecule called a plasmid, along with all the regulatory DNA elements needed to control the gene, and then inserted that DNA into the genome of a mouse embryonic stem cell line we were culturing in plastic dishes in the lab. We then injected the genetically modified stem cells into a 90-cell mouse embryo called a blastocyst, implanted it into a female mouse’s uterus, and waited about twenty days for a baby mouse to show up.
