Rewriting Inherited Disease: The Promise of Mitochondrial Donation

Writer: Maha Berrada

Editor: Niharika Ojha

Mitochondrial donation, often called “three-parent IVF”, is a new way of helping some women have healthy, genetically related children when they carry mitochondrial diseases (such as Leigh syndrome, MELAS syndrome, and many more). These diseases happen because of harmful mutations in tiny parts of every cell called mitochondria, which act like the cell’s power plants and have their own DNA.

In normal reproduction, a baby gets most of its DNA from its parents’ nuclear DNA, a large set of genes that makes you who you are. But mitochondria have a small amount of their own DNA, which we get from our mothers. If a mother’s mitochondrial DNA has problems, her child can inherit serious diseases that affect energy-using organs like the heart and brain (Newman, 2018).

Mitochondrial donation changes this. Doctors take the nuclear DNA from the mother’s fertilized egg (which still has faulty mitochondria). They place it into a donor egg that has healthy mitochondria but has its own nuclear DNA removed. The result is an embryo with DNA from three people: the mother and father’s nuclear DNA, plus the donor’s mitochondrial DNA (which makes up less than 1% of total DNA). Because mitochondrial DNA doesn’t influence most visible traits like eye color or height, the child will genetically resemble their parents, but with a much lower risk of mitochondrial disease.

This technique isn’t just theoretical anymore. In the United Kingdom, the first country to legalize it, researchers have reported successful births using mitochondrial donation. In a 2025 study, scientists stated that eight healthy babies had been born using a method called pronuclear transfer, and that none had shown signs of the serious inherited mitochondrial disorders the technique was meant to avoid (Joseph & Molteni, 2025).

For families affected by mitochondrial diseases, which can cause seizures, muscle weakness, blindness, organ failure, and even death, traditional IVF doesn’t stop these conditions from being passed down. Mitochondrial donation gives some women the possibility of having children without these devastating genetic problems (HFEA: UK Fertility Regulator, n.d.).

Supporters see this as a major step in reproductive medicine. One commentator noted that it offers “a chance to have healthy, genetically-related children, who otherwise could not.” (Case: Mitochondrial Transfer Therapy as Enhancement Technology | Online Ethics, 2016)

But the idea of combining DNA from three people isn’t without debate. Some critics worry about the long-term effects on children and future generations, because this procedure changes DNA that can be passed down. Others point out that calling the resulting children “three-parent babies” can be misleading, since the donor’s contribution is tiny and doesn’t make the donor a legal parent. In jurisdictions like the UK, donors don’t have parental rights, and children usually can’t find out the donor’s identity (HFEA: UK Fertility Regulator, n.d.). In some countries, including the United States, the procedure remains banned or heavily restricted because of these ethical concerns.

Mitochondrial donation is a new and powerful reproductive technique that can prevent serious inherited diseases while allowing parents to have genetically related children. Though still debated ethically and regulated differently around the world, recent real-world results show it can work and give hope to affected families.

References:

1. Newman, C. (2018, October 19). Q&A: Exploring the ethics of ‘Three-Parent Babies.’

https://archive.news.virginia.edu/content/qa-exploring-ethics-three-parent- babies/

2. Joseph, A., & Molteni, M. (2025b, July 16). Births of eight healthy children show promise of mitochondrial replacement therapy. STAT.

https://www.statnews.com/2025/07/16/ivf-first-births-mitochondrial- replacement-therapy-united-kingdom/

3. HFEA: UK fertility regulator. (n.d.). Human Fertilisation & Embryology Authority (HFEA).

https://www.hfea.gov.uk/treatments/embryo-testing-and-treatments-for- disease/

4. Case: Mitochondrial Transfer Therapy as Enhancement Technology | Online Ethics. (2016).

https://onlineethics.org/cases/ethics-human-enhancement-collection/case- mitochondrial-transfer-therapy-enhancement