Listening to Sharon Bernardi, a mother who lost all seven of her children to mitochondrial disease, speaking on BBC News last week, you’d wonder what kind of monster could possibly oppose three-parent embryos. Who would actively wish suffering on a child, if disease could be prevented? Framed this way, it’s tough to be the person who stands up and says ‘no’ to mothers like Ms Bernardi.
Three parent babies can be created by a technique called mitochondrial replacement, in which defective mitochondrial DNA from the egg of one woman is replaced with the healthy mitochondrial DNA from another woman. The aim is to prevent children who might suffer from mitochondrial disease from being born. While children created by this technique would be free from disease they would be genetically related to three people: two mothers and a father.
Currently, the procedure is illegal: the Human Fertilisation and Embryology Act, which governs the use of reproductive technology in the UK, prohibits the creation and use of genetically modified embryos. Government ministers now want to allow the procedure, and MPs will debate whether to change the Human Fertilisation and Embryology Act. If they’re successful, the UK will be the first country to cross a legal and ethical line unilaterally observed by the international community.
International consensus holds that genetic engineering technology shouldn’t be used to manipulate the characteristics of future children. The human germline – egg and sperm cells that pass on genes from generation to generation – would be altered, irrevocably. Modifications made to mitochondrial DNA would be passed on to descendants.
Supporters of mitochondrial transfer say mitochondrial DNA is an insignificant part of the human genome, only affecting the way cells are powered rather than physical appearance. They say tampering with it will have no ill effects. In truth, scientists don’t know enough to be sure, as this geneticist explains in journal of science Nature: “Although proof of safety is, by definition, impossible in this situation, the evidence submitted up to now is far from reassuring.”
Sharon Bernardi says mitochondrial replacement technology “is trying to make children survive.” This is the standard line from officials, who say the technique will ‘save lives’. In actual fact, the technology does nothing to help children survive mitochondrial disease – it ensures that children who might have a disease to survive are never born in the first place. It only saves lives in the sense that it prevents life-threatening disease, which is not really ‘saving lives’ at all when you stop to think about it. When you stop to think about it, it’s eugenics. Yes, that practice aimed at improving the genetic quality of the human population, the one that got a bad rep thanks to the Nazis. Does the UK really want to be the first society since Nazi Germany to go down that road?
Mitochondrial replacement isn’t a treatment for mitochondrial disease and doesn’t do anything to help those already living with the disease. What it does do is offer a small number of women like Sharon Bernardi the chance to have healthy children who are genetically related to them.
It’s only natural to want one’s own children, but having a baby – let alone having a perfect baby – is not every woman’s right. Ministers should think carefully about how future generations will judge us if we become known as the society who allowed the human germline to be tampered with – to who knows what consequences – just so a minority of women could have perfect babies.