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When the first baby to be conceived using a technique that mixes genetic material from three people was born, in 2016, scientists worried that the procedure had not been studied to show it was safe. Now, scientists in China have conducted the first comprehensive study of the technique in early-stage human embryos, and report that it does not seem to affect their development1.
Clarification 08 September 2022: A quote from Min Jiang about the nucleus’s possible preference for maternal mitochondria was not clear. She meant the nucleus might prefer maternal mitochondria over that from a donor.