Authors

Giulia Cavaliere, Department of Global Health and Social Medicine, King’s College London

César Palacios-González, Centre of Medical Law and Ethics, Dickson Poon School od Law, King’s College London

Full Paper: Lesbian Motherhood and Mitochondrial Replacement Techniques: Reproductive Freedom and Genetic Kinship [open access]

Since the UK parliamentary vote that led to their approval in February 2015, mitochondrial replacement techniques (MRTs) have been in the news a lot. We would even go all in and claim that MRTs have almost been in the news as much as another technology, also known among experts as the queen of the apples of discord (a.k.a. gene editing with CRISPR). For some, MRTs are about eugenics chambers and three-parent babies. At the extreme, they are considered a dangerous development that will facilitate the creation of Frankensteins and bring back Hitlers, and may be the first step of a very slippery slope towards Gucci-babies. For those arguing from a different moral point of view, the stakes of MRTs are just as high: these techniques could be used to relieve “the burden of human existence” and to allow women at risk of transmitting mitochondrial DNA (mtDNA) diseases to their offspring to have healthy offspring that are genetically related to them.

But what are MRTs?

Every cell of our body (except red blood cells) contains mitochondria, organelles responsible for producing the necessary energy for cellular, organ and bodily function. Mitochondria have their own DNA (mitochondrial DNA or mtDNA), which accounts only for about 0.1% of our genetic material and is inherited via the maternal line. Mutations in the mtDNA can cause mitochondrial diseases, a cluster of neuromuscular diseases in which symptoms vary in severity and expression and which can develop immediately after birth or later in life. In order to avoid the transmission of mtDNA diseases from mother to child, scientists have developed two techniques – pronuclear DNA transfer and maternal spindle transfer – that would allow women that are known carriers of mtDNA mutations to have children that are genetically related to them without risking transmitting mutated mtDNA. The two MRTs work slightly differently, but both entail the use of the mtDNA of a donor (contained in an enucleated cell), the nuclear DNA of the prospective mother and the sperm of the prospective father (or donor). Both also raise similar ethical questions that have become a matter of academic debate in the past few years.

A particularly salient point in the policy debate regarding MRTs has been on who should be allowed to access them. Following the parliamentary vote of February 2015, the UK became the first country to allow these techniques, and it also recently became the first country to give the green light for their use in the clinic by women at risk of transmitting mtDNA diseases to their children. Despite all these ‘UK first(s)!’, MRTs have already been used elsewhere – in the US / Mexico for instance. MRTs have not only been used by prospective parents at risk of transmitting mtDNA disease but, in Ukraine for instance, they have been used to ‘treat’ infertility. It has been theorised that: a) MRTs could be used as a last resort by infertile couples to increase the chances of avoiding embryonic arrest (we still await empirical evidence of this) and, b) by lesbian couples who want to have children that are genetically related to both of them. It is this second theoretical issue that we have recently explored.

Because one of us has written extensively on the ethics of MRTs and because the other of us is a contrarian, in our paper we do not discuss whether MRTs are ethically acceptable (although we both have our view on this question). Instead, we focus on another question concerning MRTs, namely: what is the ethical rationale for offering these techniques to women that are at risk of transmitting a mtDNA disease, and not to offer them to other couples, for instance lesbian couples?

In our paper we argue that no MRTs can be considered therapeutic as they do not cure children/embryos affected by mtDNA diseases, but they are rather a means to create children that are not affected by mtDNA diseases. For this reason, the rationale to offer them and to limit their access to women at risk of transmitting mtDNA diseases cannot be based on how the welfare of a particular child will be improved. Thus, the rationale to offer these techniques must then lie elsewhere. Luckily for you, we have a candidate: the rationale to offer MRTs is to allow women at risk of transmitting mtDNA disease to have healthy children that are genetically related to them. The rationale, in other words, is to expand these women’s reproductive freedom, i.e. the freedom to make significant choices (in this case having genetically related healthy babies) in matters of procreation without third parties’ interference. Reproductive freedom is known to have a limit: harm to others. According to the dominant politico-liberal account, people are free in matters of procreation so long as their choices do not inflict harm to others. Since MRTs are a means to create healthy children, they do not inflict harm to these future children (unless these children’s lives are not worth living). For this reason, these technologies fall within the proper remit of the reproductive freedom of women with mtDNA diseases and, we contend, the current UK legislation on MRTs benefits women at risk of transmitting an mtDNA disease (and their partners). It does so as it adds a qualitatively significant new reproductive option, one that allows them to have healthy genetically related children (if they wish to do so). At the same time, (explicitly) legislating against MRTs would violate these women’s reproductive freedom by restricting their significant range of reproductive options and the possibility of enjoying genetic parenthood.

But then what happens to lesbian couples?

In our view, the moral reasons for making MRTs available to women at risk of transmitting an mtDNA disease, ceteris paribus, also ground their access to lesbian couples as: a) people have a great interest in reproduction because of how it shapes their lives according to the values and interests which are relevant to them, and it is also a very deep personal and private project which has a significant impact on individuals’ well-being and b) the fact that MRTs cannot be said to harm any child created through their use. Both a) and b), then, apply to women at risk of transmitting mtDNA diseases as well as to lesbian couples who wish to share genetic parenthood of their children.

Providing access to MRTs to women at risk of transmitting a mtDNA disease and not to lesbian couples is in our view contrary to one of the tenets of morality, which demands to treat like cases alike. Denying access to MRTs to lesbian couples is morally unjustifiable in as much as it curtails the enjoyment of certain freedoms to a certain group without good reason, whilst allowing others to enjoy the very same freedoms. This prohibition requires ethically sound and better reasons than the ones presented so far.