Parthenogenote-derived brain unveils the critical role of paternal genome in neural development.

Genomic imprinting, an epigenetic mechanism that governs parent-of-origin-specific gene expression, is essential for mammalian development, yet its role in late-stage development remains unclear due to the lethality of parthenogenetic (Pg) embryos. Here, we establish cell replacement with parthenogenote-derived cells (CReP), a blastocyst complementation strategy that enables survival and tissue-specific contribution of Pg-derived cells. By creating tissue-specific niches in recipient embryos, CReP allows targeted incorporation of Pg-derived cells into late-stage tissues. Brain-targeted CReP showed that Pg-derived cells can participate in neural development but exhibit impaired maintenance of neuronal-glial balance, accompanied by increased Notch signaling and reduced expression of the paternally expressed gene Dlk1. Recombinant Dlk1 attenuated Notch activity and shifted neuronal differentiation toward control levels. These findings support a key contribution of the paternal genome to neural stem cell expansion and balanced cell fate decisions, in part through Dlk1-Notch-related pathways. The CReP model provides a powerful platform for investigating genomic imprinting and parental genome contributions in development and disease.