show Abstracthide AbstractOur lab first derived mouse androgenetic haploid embryonic stem cells (AG-haESCs) and demonstrated that AG-haESCs can be used as an “artificial spermatids” to generate gene-edited semi-cloned (SC) mice through intracytoplasmic injection (ICAHCI) into mature oocyte, even though the birth efficiency is very low. Further we proved that H19-DMR and IG-DMR were the main barrier to generate viable mice through androgenetic and parthenogenetic haESCs. More importantly, AG-haESCs mediated SC technology combined with CRISPR-Cas9 is a powerful tool to generate gene-modified mouse models and carry out genetic screening at organismal level. However, it is still not clear how the H19-DMR and IG-DMR coordinately regulate SC embryo development. Here, we found that the H19-DMR and IG-DMR regulate the development of SC embryos in spatio-temporal scales. Firstly, we found that the H19-DMR and IG-DMR are not indispensable for the development of preimplantation of SC embryos. Secondly, H19-DMR is essential for the development of SC embryos in mid-gestation and IG-DMR takes effect in late-gestation. Further, the maintenance of paternal H19-DMR methylation status and deletion of paternal H19 transcription unit play a key role in the structures and transport functions of SC embryo placenta. Importantly, AG-haESCs carrying triple deletions, including H19, H19-DMR and IG-DMR, can further improve the efficiency in generation of viable, normal-size, and fertile mice. Overall design: For blastocyst, five samples (including ICM and TE) for control (ICSI) and semi-cloned blastocysts (including WT and DKO). For placenta, three samples for control (ICSI) and semi-cloned placentae (including WT, DKO, IG?DMR and H19?13kb)