Cloning has an unexpected problem.

This article focuses on a 20-year study revealing that cloning does not produce genetically identical copies, as clones accumulate significantly more mutations than naturally reproduced animals. The research, led by Teruhiko Wakayama at Yamanashi University, found that repeated cloning of mice over multiple generations led to a buildup of harmful mutations, ultimately causing clone failure by the 58th generation. The study suggests that mutations may arise both from the adult donor cells used in cloning and potentially from the nuclear transfer process itself, though some experts argue mutations primarily reflect the donor cells' genomic state. These findings have important implications for cloning applications in farming, de-extinction, and medical treatments, highlighting the need for careful donor cell selection and mutation screening. [Extracted from the article]