| Type | MGI:General | Description | 30% of 5.5 dpc homozygous null embryos displayed complete loss of architecture with a high number of pyknotic cells showing karyorrhexis and karyolysis pre-implantation embryos displayed a complete absence of nonsense-mediated mRNA decay (NMD), which is thought to protect organisms by preventing the translation of aberrant (truncated) proteins with dominant negative or gain-of-function activities |