Babies born with three parents could soon be a reality, with a controversial fertility treatment about to progress to human trials.
British scientists behind the treatment set out to create embryos free of hereditary mitochondrial disease with a technique that removes diseased cells from the expectant mother and replaces them with healthy ones from an egg donated by another woman.
Mitochondrial disease is responsible for 50 genetic and life-threatening diseases, and can lead to serious illness for one in 6500 babies, The Daily Mail reports.
Women who carry damaged mitochondria often face multiple miscarriages and the heartbreak of a childless future.
The new fertility process means, as well as DNA from the mother and father, the embryo created has a small amount of mitochondrial DNA from the donor egg.
While the technique could provide the answer many would-be parents desperately hope for, critics argue the engineered embryos cross ethical lines and put women at risk.
British law was changed last year to allow the technique to be used and now researchers believe they have proven the technique is safe enough to be offered to women.
Tests on the more than 200 three-parent embryos grown until they were up to six days old showed them to be of the same quality as those embryos created via conventional IVF.
But tests also showed while the diseased DNA could be made low enough to create healthy babies, it could not be eliminated completely so the babies could become ill later in life.
“The key message is that we have found no evidence the technique is unsafe,” co-researcher Doug Turnbull says.
“Embryos created by this technique have all the characteristics to lead to a pregnancy.”
However, the New York Stem Cell Foundation Research Institute’s Dr Dieter Egl says fears the diseased mitochondria might multiply mean it is too early to use the technique.
Science has come a long way since Australia’s first IVF baby Candice Flum was born 36 years ago.