Mitochondrial donation was developed as a way to prevent babies from inheriting life-threatening mitochondrial diseases from their mothers. However, as part of a trial conducted between Spanish company Embryotools and the Institute of Life IVF Centre in Athens, Greece, the procedure was used for the fertility treatment of a woman with poor egg quality.
'We are now in a position to make it possible for women with multiple IVF failures or rare mitochondrial genetic diseases to have a healthy child,' said Dr Panagiotis Psathas, president of the Institute of Life clinic. Dr Nuno Costa-Borges, scientific director of Embryotools added: 'The completely successful and safe implementation of the maternal spindle transfer method – for the first time in medical history – is a revolution in assisted reproduction.'
The procedure, known as maternal spindle transfer, involves extracting the nucleus from a mother's egg and transferring it into a donor egg, which has had its nucleus removed. This combined egg is then fertilised with the father's sperm and implanted into the mother. The resulting embryo has chromosomes from the mother and father, but also retains mitochondrial DNA from the donor.
The doctors' claims of novelty and safety have been questioned. A previous birth following maternal spindle transfer occurred in Mexico in 2016, to a woman affected by the mitochondrial disease Leigh Syndrome (see BioNews 871). An alternative mitochondrial donation method – pronuclear transfer – was used for infertility in Ukraine (see BioNews 885) in 2017.
Alastair Sutcliffe, professor of general paediatrics at UCL, who was not involved in the work, commented: 'The curious thing is the claim that it is safe after the birth one of one healthy baby.'
The application of mitochondrial donation to treat infertility has also raised ethical concerns.
Medical director of the Fertility Partnership and professor at the University of Oxford, Tim Child, said: 'I'm concerned that there's no proven need for the patient to have her genetic material removed from her eggs and transferred into the eggs of a donor. The risks of the technique aren't entirely known, though may be considered acceptable if being used to treat mitochondrial disease, but not in this situation.'
In this case, the 32-year-old mother had undergone four unsuccessful rounds of IVF treatment and had poor egg quality. Although she was not at risk of passing on mitochondrial disease to her child, she was put forward for the trial since scientists have speculated that higher mitochondrial function in eggs may increase the chances of successful IVF. This has not been proved.
The trial continues. 24 other women are participating, with eight embryos currently ready for implantation.