In order to avert children from acquiring life-threatening genetic diseases Sydney scientists are now eager to create designer babies with the DNA of three parents.
IVF specialists have argued that they could wipe out mitochondrial mutations - which can lead to multi-organ failure and fatal heart, liver and muscle conditions - by removing defective genes and replacing them with healthy DNA from a donor.
The procedure, described by scientific opponents as "fraught with danger", would ensure women with the severe genetic condition do not pass it on to their children, the Daily Telegraph reported.
But Professor Illingworth defended the procedure, insisting that it was "not properly understood" and "would not affect the child's genetic make-up."
He asserted the genes that determined behaviour and appearance came from the nucleus of the cell and not the mitochondrion.
The illness impacts the way a body converts food into energy and can cause strokes, seizures, growth problems, hearing problems and organ failure.
"We want to remove the mother's bad mitochondria and replace it with healthy mitochondria through IVF," Professor Illingworth said.
"We know women who have a defective mitochondria pass that on to their children.
"About one child a week is born in Australia with a mitochondrial condition. It is rare but very debilitating."
In Australia scientists are barred from using the DNA of more than two people in any research.
But the federal government is reviewing the Research Involving Human Embryos Act after a report was tabled in Parliament last year.
Professor Illingworth said scientists expect that the government would amend the law to allow research into embryo transfers.
"The health implications of these diseases are so serious this research should be allowed," he added.