Fertile Mice With Two Fathers Produce Their Own Offspring

A team led by Yanchang Wei at Shanghai Jiao Tong University injected two sperm genomes into enucleated eggs and used epigenome editing to target seven imprinting control regions Two of 259 implanted embryos matured into healthy adult males that subsequently fathered normal-appearing offspring with female partners The findings confirm genomic imprinting as the primary developmental barrier to uniparental mammalian reproduction and show it can be bypassed through precise epigenetic reprogramming The overall survival rate remains below 1 percent and depends on egg donors and surrogate mothers, making the method impractical for human application today This approach modulates methylation patterns without altering DNA sequences, distinguishing it from earlier genetic modification attempts that yielded infertile or unhealthy mice