Fig. 1

Strategies to generate offspring with haESCs. a Intracytoplasmic injection of androgenic haESCs (AhaESCs) in early and late passages. AhaESCs can produce live offspring only in early passages, because of the loss of paternal imprinting in long-term cell culture processes. This reduces developmental potential of AhaESCs. b By replacing the female pronucleus with parthenogenic haESCs (PhaESCs), the fertilized zygote can produce healthy progeny. c By knocking out the H19-DMRs and IG-DMRs of haESCs (AhaESCs and PhaESCs), genetically modified haESCs can efficiently produce mice via intracytoplasmic injection. DMR differentially methylated region, haESC haploid embryonic stem cell