A cell with the nucleus and mitochondria labelled (Image: Wellcome Images)
The UK Government is considering legalising a specialised form of IVF called mitochondrial donation, which aims to prevent potentially fatal mitochondrial disease. As Parliament prepares to debate the issue on Monday 1 September, Jane Bunce tries to clear up confusion over the science behind the technique ― and explains why it will not lead to creation of “designer babies”.
What is mitochondrial disease?
An estimated one in 6,500 children will develop a serious mitochondrial condition, which is passed down from mother to child. There is no cure and symptoms include seizures, strokes, blindness, deafness, heart and liver failure ― and in serious cases, death at a young age.
The diseases are due to faults in a child’s mitochondria, which are often described as the “battery packs” of our cells. These mitochondria are small structures in human cells that convert the food we eat into energy we need to stay alive. If these mitochondria don’t work correctly, cells don’t have enough energy and the tissues or organs they make up do not function properly. Read more
The University of Newcastle’s Doug Turnbull is part of a team (with Professors Mary Herbert and Alison Murdoch) that is developing a technique to prevent inherited genetic conditions called mitochondrial diseases. ‘Mitochondrial transfer’ replaces a woman’s faulty mitochondria with those of a healthy donor, and combining the technique with IVF could mean affected women no longer pass on these diseases.
As the public consultation on whether to change the law to allow mitochondrial transfer draws to a close, Katherine Nightingale talks to Doug about the technique, why it’s needed and what it’s like to be working in a potentially legislation-changing field.
Will we have heard of any of these mitochondrial diseases?
The diseases affect the mitochondria — the ‘batteries’ of the cell that produce the energy cells need to function properly. You might not have heard of them; some, such as Leigh’s syndrome, have been known for many years among doctors and researchers but the collective term of mitochondrial diseases isn’t well known among the public, even though around 1 in 6,000 children is born with some kind of mitochondrial disease. The diseases most affect the parts of the body that use the most energy: the brain and nervous system, muscles and other major organs such as the heart and liver.
The intriguing thing about mitochondria is that they have their own DNA, separate to the DNA in a cell’s nucleus. The affected genes in mitochondrial diseases are in this mitochondrial DNA, meaning they are inherited differently to other genetic diseases — only mothers pass them on to their children through their eggs. Read more