Issue Briefing: ‘Mitochondrial Donation’ (‘Three Parent Embryos’)
Tomorrow, the House of Commons Science and Technology (SciTech) Committee will hold a one-off inquiry on the issue of mitochondrial donation techniques, which would amongst other things involve the destruction of embryonic human beings, and the creation of new human beings with the DNA of three or even four parents. This comes in the context of the decision of the Human Fertilisation and Embryology Authority (HFEA), the Government body responsible for allowing research and medical practices on human embryos to allow such practices, and the consequent Government decision to regulate their legal use.
What follows is a briefing on the issue, adapted from the submission Right To Life gave to the HFEA consultation:
What is Mitochondrial Donation?
Mitochondria are small sub-units within a cell that act as its digestive system – taking in nutrients, breaking them down, and creating energy for the cell. These also contain genetic material, and the mitochondria within the ova (female eggs that, when fertilised by male sperm, become new human beings) of some women can pass on genetic disease. Mitochondrial donation techniques are practices designed to allow women who pass on inherited genetic diseases through the mitochondria within their ova to have children and avoid such disease being passed on. They would do this by one of two techniques that have hitherto been considered: ‘Pro-Nuclear Transfer’ (PNT), and ‘Maternal Spindle Transfer’ (MST). The HFEA are also considering another technique known as ‘Polar Body Transfer’ (PBT), but this is a very recent development which has thus far gone un-discussed in Parliament.
What is Pro-Nuclear Transfer (PNT)?
Pro-Nuclear Transfer (PNT) involves creating two embryos through in-vitro fertilisation (IVF): one from the egg and sperm of the intended mother and father containing diseased mitochondria, and another through the egg of a second woman and either the father or a second man that contains healthy mitochondria. The pro-nuclei (the core, or ‘brains’ of the cell that contain the DNA of the embryonic human being) of both embryos are then removed and the pro-nuclei of the mother/father embryo is then put into the body of the second embryo containing healthy mitochondria. PNT thus destroys two embryonic human beings to create a third human being who would have four parents (the intended mother and father of the first embryo containing the used pro-nuclei, and the second woman and man whose sperm and egg created the second embryo with the healthy mitochondria).
What is Maternal Spindle Transfer (MST)?
Maternal Spindle Transfer (MST) involves taking two female eggs: the egg of the intended mother containing diseased mitochondria, and an egg from another woman containing healthy mitochondria. The nuclei from both eggs is then removed, and the nucleus from the mother’s egg is inserted into the healthy one. So, the ‘maternal spindle’ (the mother’s nucleus) is transferred from her own egg to another woman’s egg that has healthy mitochondria. This new egg would then be fertilised with the sperm of the intended father through IVF. MST thus creates a baby who would have three parents (the intended mother and father, and the second woman whose egg was donated for the procedure).
What is the problem with either of these techniques?
1) They violate human dignity by creating multi-parent embryos:
Insofar as it involves making a zygote from the gametes of three people, MST is contrary to the dignity of the child created from that process, who would suffer as a consequence from identity problems generated by the fact that he/she would have, in effect, two biological mothers yet one father. In fact, with MST both the female donors of the nucleus and the egg are really only partial ‘mothers’ given the split proportion of the maternal genetic heritage of the child.
These same problems also exist with PNT, which, whilst apparently thought of as the ‘simpler’ option, is also the ethically gravest one. PNT constitutes an act of reproductive cloning that engineers a child with genetic ancestry but without genetic parents (since that child would be a product of two destroyed zygotes, not a mother and a father). In PNT, the donor of the oocyte with healthy mitochondria is only the mother of one of the embryonic human beings destroyed in order to create the clone, not the clone him/herself.
A defence is made that, given the small proportion of the genetic material provided by the person whose mitochondria form part of the created child (mitochondria contain only 0.1 per cent of total human DNA at that stage of development), and also given that they will be totally uninvolved in the child’s upbringing, such people are not really parents so much as ‘mitochondria donors’. This language is, however, essentially misleading, as it is not the mitochondria themselves that are being transferred in either MST or PNT but the nuclear genes (the spindle or the pro-nuclei), which are themselves transferred either into a ‘donor’ egg or else the ‘shell’ of a previously destroyed zygote. And regardless of the proportion of the genes provided, or that these individuals will have no role in the upbringing of the child, the very definition of biological ancestry is that their genes have gone into the creation of this new person. Equivocating over the social parentage of the child, or emphasising the irrelevant detail of the proportion of genes involved, can in no way refute this point.
No child should be intentionally deprived of knowledge of their biological parents (or, perhaps more accurately in the case of PNT, ‘ancestral progenitors’), however confused this may be due to the manner of their conception. It is impossible to see how it would be justifiable for children conceived through either MST or PNT to have fewer rights than other children conceived through IVF.
2) They involve the instrumental manipulation and destruction of artificially-created human beings:
In the process of PNT, two zygotal human beings are destroyed in order to create a third. Both the original zygote who had diseased mitochondria, and the donor zygote with healthy mitochondria, are essentially destroyed when their pronuclei are removed. A third zygote is then created when the transferral of the pronuclei of the original zygote into the donor zygote takes place.
This destruction of zygotal human beings constitutes a violation of their Rights to Life as defined in the Universal Declaration of Human Rights (UDHR), which applies, as it says in its Preamble, to “all members of the human family”. Article 3 of the UDHR states that “Everyone has the right to life”, and Article 6 states that “Everyone has the right to recognition everywhere as a person before the law”. Moreover, Article 6 of the United Nations Convention on the Right of the Child (UNCRC), which exists, as it states in its Preamble, because “the child… needs special safeguards and care, including appropriate legal protection, before as well as after birth” [italics added]), and which states that “every child has the inherent right to life” and commits all the signatories of the Convention (which includes the UK) to “ensure to the maximum extent possible the survival and development of the child”.
3) They are not proven to be safe, and adverse consequences will be impossible to ascertain:
MST as a process also carries unquantifiable physical risks. Oregon researchers who used MST found that half of the embryos created were abnormal, and neither they nor counterparts in Newcastle implanted human embryos used by this technique. Yet it will not be possible to monitor the effects of these procedures in the future. The only way of tracking the long-term effects of MST and PNT in the long-term is monitoring the people who began as PNT or MST embryos and their descendants. Yet not only would it be impossible (quite rightly) to force individuals to participate in such research, there would be no requirement of MST or PNT adults to disclose to their partners their genetic inheritance (assuming they are aware of it in the first place). The effects of such techniques will thus be completely impossible to ascertain.
4) They involve genetic engineering of the human germ-line, violating an internationally-recognised ethical convention:
Finally, both MST and PNT cross the ethical line into germ-line genetic engineering. This means that the ‘germ-line’ (the genetic inheritance of humanity) would be being artificially and irrevocably altered. Any change in this area, and any allowance for genetic manipulation of the germline, will affect future generations in ways that are impossible to predict. The Council of Europe’s Convention of Human Rights and Biomedicine explicitly condemns this as does the World Health Organisation which has stated fairly comprehensively that “where there is an intention or possibility of altering genes passed on to the next generation [this] should not be permitted in the foreseeable future”. Additionally, the beginning of the use of these processes would cross an ethical line of principle that would allow and enable use of these and similar actions to solve other medical conditions and indeed for other reasons outside medicine.
All of this makes mitochondrial donation techniques contrary to human dignity and the common good, and given such risks, it is no accident that these practices are illegal across the advanced world from the U.S. to Europe. They are also utterly unnecessary, as standard IVF (though itself ethically objectionable) already avoids passing on mitochondrial disease. All other things being equal, no child created by MST/PNT would be healthier than children conceived using standard egg donation. For purposes of prudence and precedent if nothing else, neither MST nor PNT should be allowed as practice either in IVF or in future research.
Given all these problems, why is this being done?
The only possible ‘beneficial’ difference between MST/PNT and current IVF, is that the former satisfy the desire by some parents for a child who would be genetically related to both mother and father (however partially in the case of the mother). This is very understandable in what is often a hugely difficult family situation. Yet these ends could not possibly justify the effective legalisation of reproductive cloning, genetically modification of children, or altering the human germ-line, still less the instrumental destruction of the most vulnerable of all human beings.
What can I do about this?
Please write to your MP, alerting them to these issues, and asking them to sign EDM 858 and to oppose the licensing of such procedures. You can also make the point that given the recent history of reproductive technology, there is no practical reason to believe, if these two techniques were to be allowed, that any regulator would effectively provide a safeguard against their use being expanded. For this reason, the rules governing the use of such technologies would best be defined by the democratic process, in Parliament.