Science is celebrating a groundbreaking achievement this year, after the birth of the world's first baby created using a new 'three person DNA' technique.
The child, born on 6 April, was conceived using a new technique that could revolutionise how babies are created in future.
The technique, called mitochondrial transfer, involves the nucleus from one of the mother's eggs being inserted into a donor's egg, which has already had its own nucleus removed. This hybrid egg is then fertilised with the father's sperm.
The controversial procedure, which has so far only being legalised in the UK, gives hope to women who carry a genetic disease that they do not want to pass on to their child. In this case, the mother was carrying the gene for the fatal Leigh syndrome in almost one-quarter of her mitochondria (a structure found in every cell of our bodies). She had already passed the gene onto two of her previous children, who had both died, and suffered from four miscarriages.
Wanting to give birth to a healthy child, the mother contacted Doctor John Zhang, from the New Hope Fertility Center in New York, to request his help.
As mitochondrial transfer is still illegal in the US, Dr Zhang and his team travelled to Mexico, where "there are no rules", to perform the successful procedure.
He told the New Scientist, "To save lives is the ethical thing to do".
The team of doctors created five human embryos using the technique, although only one developed normally and was eventually implanted into the mother.
Speaking about the birth to The Guardian, Dusko Ilic, a stem cell scientist at King’s College London, said, "Without much ado, it appears the first mitochondrial donation baby was born three months ago. This was an ice-breaker. The baby is reportedly healthy.
"Hopefully, this will tame the more zealous critics, accelerate the field, and we will witness soon the birth of the first mitochondrial donation baby in the UK."