John Gordon20y of mouse cloning: “These re-cloned mice appeared normal and had normal lifespans, but large structural and lethal mutations accumulated in their DNA with each generation”
https://www.nature.com/articles/s41467-026-69765-7
It took a long time to manifest as illness!
Limitations of serial cloning in mammals - Nature Communications
Here they show that extended serial somatic cell cloning imposes a threefold increase in de novo mutations compared to natural reproduction, progressively reducing birth rates and ultimately limiting clonal propagation to 58 generations.
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