Page URL:

Video Review: A groundbreaking way to stop mitochondrial disease – TedMed

29 October 2018
Appeared in BioNews 973

'Every time somebody decides to have a baby, they're engaging in a game of Russian roulette,' argues  Professor Mary Herbert, a reproductive biologist at the University of Newcastle. Around 60-70 percent of fertilised eggs will never make it to pregnancy. You could see simply being here as a sign that we have beaten the odds. 

'We are all survivors – well done,' she congratulates the audience.

Professor Herbert, scientific director of the Newcastle Fertility Centre, presents a clear and concise narrative of her team's research, ultimately resulting in a novel solution of mitochondrial donation for use in the clinic.

Whether an embryo develops into a healthy baby is largely dependant on the DNA inherited from the two parents, she explains. An embryo contains three sets of genetic information or DNA: two nuclear genomes, one from each parent, packaged into chromosomes. The third is present in the mother's ovum in the form of mitochondrial DNA (mtDNA). 

Given that the mtDNA consists of only 37 genes you might easily disregard the importance of the genetic information stored here – you would be wrong. Professor Herbert explains that the main function of the mitochondria is to produce the energy required by our cells to survive; the genes encoded in the mtDNA are essential for these processes. When these genes are disrupted by, for example, a mutation, a broad range of debilitating and often fatal conditions can result.

This is where Professor Herbert's own research comes in, on the prevention of the transmission of mtDNA disease by transferring nuclear material to an enucleated donor cell. We have reached the crux of her talk, as she goes into the proof-of-concept investigations her lab did after patiently obtaining a licence from the UK regulator, the Human Fertilisation and Embryology Authority. This took over a year to be granted. It is perhaps a residual lack of patience now that makes Professor Herbert fly through allusions to various ethical considerations and legal hurdles that were necessary to overcome before they could start their investigations. 

The work performed by Professor Herbert and her colleagues has also been integral to a change in UK law to permit the use of mitochondrial donation within the clinic. Here the talk would have benefited from a more thorough discussion of these areas, allowing the viewer a further understanding of the considerations for and against as well as the potential real-world impact of the group's work.

With the aid of an illustrative video of the kind of microsurgery they conduct in the lab, we watch as the almost invisible pronuclei are evacuated from the cell of a carrier and carefully injected into the cell of a healthy donor. A remarkably high proportion – 95 percent – of these injected cells survive. This technique proffered by Professor Hubert and her colleagues allows potential mothers who are known carriers of disease-causing mtDNA to have genetically related children without the risk of passing on the condition.

Professor Herbert continues her talk, introducing the idea of so-called three-person babies, which emerged during a period of intense media interest in their work. This notion is dismissed by Professor Hubert as a misnomer since the mtDNA that is provided by the third individual (an egg donor) does not contain DNA that would encode any of the characteristics considered responsible for making an individual unique. 

Her straightforward pronouncement of this argument is clearly reflective of her opinion on the ethical implications of their research. It would have been more interesting, had Professor Herbert gone into more detail on the questions and conflict that this unprecedented media coverage created. 

Professor Herbert's fact-driven and frank presentation was brought into perspective as she recounts meeting a woman of a similar age to herself, fast succumbing to a mitochondrial disease. The woman found it 'deeply consoling' that her daughters' lives would not be blighted by the fear of transmitting it to their children, she told Professor Herbert.

The talk finishes by thanking the many women who have generously donated their eggs in order to, 'give the gift of health not just to one child but to generations of children to come'. This new and extraordinary treatment grants us the ability to not simply treat a single child, but to effectively eliminate the disease.

28 January 2019 - by Jen Willows 
Greek and Spanish researchers have announced that a clinical trial using mitochondrial donation to treat infertility has resulted in a pregnancy...
1 October 2018 - by Dr James Heather 
Two research groups have, for the first time, used genome editing to successfully treat mitochondrial disease in animals...
2 July 2018 - by Sarah Pritchard 
Australia may become the second nation to legalise mitochondrial donation, after its Senate endorsed the so-called 'three-person IVF' technique in a recent report...
14 May 2018 - by Dr Owen Schaefer 
Amid international debate on mitochondrial donation, Singapore's Bioethics Advisory Committee has prompted much discussion nationally over the issue...
5 February 2018 - by Dr Sam Sherratt 
The Human Fertilisation and Embryology Authority (HFEA) has granted permission for doctors to create the UK's first 'three-person' children by mitochondrial donation.
to add a Comment.

By posting a comment you agree to abide by the BioNews terms and conditions

Syndicate this story - click here to enquire about using this story.