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Scientists have created mice with DNA from two male fathers for the first time, though this breakthrough comes with significant hurdles. Using CRISPR gene editing, researchers disrupted 20 imprinted genes critical for mouse development, resulting in some embryos surviving and developing into pups. However, only a small fraction of these mice were viable, and those born were oversized, infertile, and shorter-lived compared to normal mice.
This method mirrors previous attempts but with less success due to technical challenges and ethical concerns—editing 20 imprinted genes in humans is not feasible without risking health consequences. Despite these hurdles, the research offers valuable insights into imprinting, where certain genes are expressed differently based on their parental origin, impacting gene regulation during development.
The study highlights progress in understanding how maternal and paternal contributions shape embryonic development but underscores the need for caution before pursuing similar bioparental approaches with human embryos.
Source: https://www.technologyreview.com/2025/01/28/1110613/mice-with-two-dads-crispr