MGI:1914192Homozygous null mice exhibit embryonic growth arrest and complete lethality before implantation. Mice homozygous for a null allele arrest at the morula stage, fail to form blastoceles, and show loss of pluripotency in early development. Mice homozygous for a different null allele show failure of morula compaction. In vitro, blastocysts fail to hatch from the zona pellucida and die after 3 days in culture.