Mammals cannot be cloned indefinitely, mice study finds
Japanese researchers produced about 1,200 clones from one mouse over 20 years and found repeated cloning led to a "mutational meltdown".
Japanese scientists say there is a limit to how many times a mammal can be cloned before suffering a "mutational meltdown." Starting from a single mouse, they produced roughly 1,200 clones over two decades and observed accumulating genetic damage that culminated in the meltdown.