The first baby with DNA from three parents has been born in Mexico, it has emerged.
The now five-month-old boy was conceived using a technique which involves a small amount of DNA from a third parent being added to the genetic material of the father and mother.
The technique is designed to avoid parents with rare genetic mutations from passing them onto their children.
News of the first successful use of the technique was revealed by the New Scientist.
The Jordanian mother of the child has genetic material in DNA in her mitochondria that can cause a fatal nervous system disorder called Leigh syndrome.
Ibtisam Shaban had already lost two of her children at ages 6 years and 8 months respectively, as a result of the genetic disorder being passed down to them.
Mitochondria provides the fuel for our cells and is home to just 37 genes that come to us all from our mothers.
The technique for avoiding the passing on of the damaged mitochondria DNA that has been approved for use in Britain involves the fertilisation of both the mother's egg and a donor egg with the father's sperm.
The nucleus of both is then immediately removed, and the nucleus from the donor's fertilised egg is replaced with the one from the mother's fertilised egg.
However, according to the New Scientist, Ibtisam Shaban and husband Mahmoud Hassan's doctor employed an alternative technique which doesn't require the destruction of two embryos because the couple are Muslims.
Instead, John Zhang from the New Hope Fertility Center in New York removed the nucleus from one of the mother's eggs, inserted it into a donor which had its nucleus removed, and then fertilised it with sperm from the father.
The procedure was carried out in Mexico, as it has no laws in this area.
The news of the first apparent success from the treatment has been welcomed by reproductive experts, who say it will help parents with genetic conditions.
However, the technique is controversial because it can involve the destruction of embryos.
There are also some safety concerns around its use due to failed attempts in the past.