News | Eight "three-person DNA babies" born in the UK, preventing inherited mitochondrial disease
UK scientists have confirmed for the first time that an IVF technique using DNA from three people can prevent mitochondrial disease from being inherited before birth. Published clinical data show that eight healthy babies have been born through the technique. All are developing normally, with disease-causing mitochondrial DNA mutations either undetectable or at levels too low to cause harm. The breakthrough offers hope to families affected by mitochondrial disease.
The technique, pronuclear transfer (PNT), was pioneered by teams at Newcastle University and Newcastle upon Tyne Hospitals NHS Foundation Trust and was legalized in the UK in 2015. After fertilization, the parents' nuclear genome is moved from an egg containing disease-causing mutations into a fertilized donor egg from a healthy woman whose nucleus has been removed. The embryo therefore contains nuclear DNA from both parents and healthy mitochondrial DNA from the donor.
Eight babies developing well, with mitochondrial mutations very low or undetectable
According to two papers published in the New England Journal of Medicine (NEJM) on July 16, 2025, seven high-risk women gave birth to eight babies—four boys and four girls, including identical twins. All newborns:
Were healthy at birth
Met developmental milestones
Had pathogenic mitochondrial DNA levels of 0%–16%, far below the threshold for symptoms
Five had no detectable maternal mutation
The team said small amounts of residual maternal mitochondria usually reflect unavoidable carryover during transfer, but the levels detected are not expected to cause health problems.
Project lead Professor Mary Herbert said:
"The data are very encouraging. But to move from risk reduction to prevention, we must continue investigating how to further reduce maternal mitochondrial carryover."
Parents' experiences: from fear of inheritance to a healthy new life
One mother who had a daughter through mitochondrial donation said:
"We were terrified of passing the disease to the next generation. Now our child is healthy and full of energy. This technique gave us a real chance."
Another mother said:
"We can finally leave behind the fear of mitochondrial disease. This technique has made our family whole again."
Mitochondrial disease affects 1 in 5000 newborns and remains incurable
Mitochondria are the cell's energy factories, and their DNA is inherited entirely from the mother. Mutations can cause serious disease, especially affecting the:
Heart
Muscles
Brain
There is currently no cure. The only strategy is to reduce transmission risk, making IVF-based techniques a major focus worldwide.
Pronuclear transfer: the science of three-person DNA
The parents' egg and sperm undergo normal fertilization
Nuclear DNA containing the parents' genetic traits is removed from the fertilized egg
It is transferred into an enucleated fertilized egg from a healthy female donor
The resulting embryo contains:
Nuclear DNA from the parents (99.8%)
Mitochondrial DNA from the donor (0.2%)
The technique is used only to address mitochondrial disease and is regulated in the UK by the Human Fertilisation and Embryology Authority (HFEA).
Clinical results: encouraging pregnancy and health outcomes
Data from the Integrated Pathway program show:
PNT:
8 clinical pregnancies among 22 women (36%)
8 babies born, with 1 additional pregnancy ongoing
The other 3 had mild early symptoms, including startle episodes, urinary tract infection and elevated blood lipids, and all recovered
No signs associated with mitochondrial disease were found
All children will be followed for at least 5 years.
Experts: a major global turning point, making inherited incurable disease preventable
Professor Bobby McFarland said:
"This is one of the most important turning points for families affected by mitochondrial disease. The children are growing healthily, and the results are encouraging."
Liz Curtis, CEO of The Lily Foundation, said:
"We have worked toward this for years. These eight healthy babies now show that the hope is real."
News | Eight "three-person DNA babies" born in the UK, preventing inherited mitochondrial disease
News | Eight "three-person DNA babies" born in the UK, preventing inherited mitochondrial disease
UK scientists have confirmed for the first time that an IVF technique using DNA from three people can prevent mitochondrial disease from being inherited before birth. Published clinical data show that eight healthy babies have been born through the technique. All are developing normally, with disease-causing mitochondrial DNA mutations either undetectable or at levels too low to cause harm. The breakthrough offers hope to families affected by mitochondrial disease.
The technique, pronuclear transfer (PNT), was pioneered by teams at Newcastle University and Newcastle upon Tyne Hospitals NHS Foundation Trust and was legalized in the UK in 2015. After fertilization, the parents' nuclear genome is moved from an egg containing disease-causing mutations into a fertilized donor egg from a healthy woman whose nucleus has been removed. The embryo therefore contains nuclear DNA from both parents and healthy mitochondrial DNA from the donor.
Eight babies developing well, with mitochondrial mutations very low or undetectable
According to two papers published in the New England Journal of Medicine (NEJM) on July 16, 2025, seven high-risk women gave birth to eight babies—four boys and four girls, including identical twins. All newborns:
Were healthy at birth
Met developmental milestones
Had pathogenic mitochondrial DNA levels of 0%–16%, far below the threshold for symptoms
Five had no detectable maternal mutation
The team said small amounts of residual maternal mitochondria usually reflect unavoidable carryover during transfer, but the levels detected are not expected to cause health problems.
Project lead Professor Mary Herbert said:
"The data are very encouraging. But to move from risk reduction to prevention, we must continue investigating how to further reduce maternal mitochondrial carryover."
Parents' experiences: from fear of inheritance to a healthy new life
One mother who had a daughter through mitochondrial donation said:
"We were terrified of passing the disease to the next generation. Now our child is healthy and full of energy. This technique gave us a real chance."
Another mother said:
"We can finally leave behind the fear of mitochondrial disease. This technique has made our family whole again."
Mitochondrial disease affects 1 in 5000 newborns and remains incurable
Mitochondria are the cell's energy factories, and their DNA is inherited entirely from the mother. Mutations can cause serious disease, especially affecting the:
Heart
Muscles
Brain
There is currently no cure. The only strategy is to reduce transmission risk, making IVF-based techniques a major focus worldwide.
Pronuclear transfer: the science of three-person DNA
The parents' egg and sperm undergo normal fertilization
Nuclear DNA containing the parents' genetic traits is removed from the fertilized egg
It is transferred into an enucleated fertilized egg from a healthy female donor
The resulting embryo contains:
Nuclear DNA from the parents (99.8%)
Mitochondrial DNA from the donor (0.2%)
The technique is used only to address mitochondrial disease and is regulated in the UK by the Human Fertilisation and Embryology Authority (HFEA).
Clinical results: encouraging pregnancy and health outcomes
Data from the Integrated Pathway program show:
PNT:
8 clinical pregnancies among 22 women (36%)
8 babies born, with 1 additional pregnancy ongoing
PGT (preimplantation genetic testing) comparison group:
16 pregnancies among 39 women (41%)
18 babies born
Newborn follow-up:
5 babies had no health problems
The other 3 had mild early symptoms, including startle episodes, urinary tract infection and elevated blood lipids, and all recovered
No signs associated with mitochondrial disease were found
All children will be followed for at least 5 years.
Experts: a major global turning point, making inherited incurable disease preventable
Professor Bobby McFarland said:
"This is one of the most important turning points for families affected by mitochondrial disease. The children are growing healthily, and the results are encouraging."
Liz Curtis, CEO of The Lily Foundation, said:
"We have worked toward this for years. These eight healthy babies now show that the hope is real."
Story source:
Collected online