The world's first baby has been born using a new "three person" fertility technique, New Scientist reveals.
The five-month-old boy has the usual DNA from his mum and dad, plus a tiny bit of genetic code from a donor.
1) Eggs from a mother with damaged mitochondria and a donor with healthy mitochondria are collected
2) The majority of the genetic material is removed from both eggs
3) The mother's genetic material is inserted into the donor egg, which can be fertilised by sperm.
US doctors took the unprecedented step to ensure the baby boy would be free of a genetic condition that his Jordanian mother carries in her genes.
Experts say the move heralds a new era in medicine and could help other families with rare genetic conditions.
But they warn that rigorous checks of this new and controversial technology, called mitochondrial donation, are needed.
It's not the first time scientists have created babies that have DNA from three people - that breakthrough began in the late 1990s - but it is an entirely new and significant method.