Haploid mammalian embryonic stem cells (ESCs) hold great promise for functional genetic studies and assisted reproduction. Recently, rodent androgenetic haploid ESCs (AG-haESCs) were generated from androgenetic blastocysts and functioned like sperm to produce viable offspring via the intracytoplasmic AG-haESCs injection into oocytes. However, the efficiency of this reproduction was very low. Most pups were growth-retarded and died shortly after birth, which is not practical for producing knockout animals. Further investigation suggested a possible link between the low birthrate and aberrant expression of imprinted genes. Here, we report the high-frequency generation of healthy, fertile mice from H19-Igf2 imprinting-locus modified AG-haESCs, which maintained normal paternal imprinting and pluripotency. Moreover, it is feasible to perform further genetic manipulations in these AG-haESCs. Our study provides a reliable and efficient tool to rapidly produce gene-modified mouse models and will benefit reproductive medicine in the future.
Keywords: AG-haESCs; Haploid ES cells; ICAHCI; gene-modified mice; imprinted gene.