EUROPEAN BIOETHICAL RESEARCH
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CHILDREN WITH TWO GENETIC FATHERS
Written by Dr. Calum MacKellar, European Bioethical Research, Scotland
An interesting situation has arisen because of a possible loop-hole in legislation being recommended to parliament in the UK. Indeed, in one of the clauses of the chief medical officer’s expert group report entitled, “Stem Cell Research : Medical Progress with Responsibility” published in August 2000, the wording is such that children could theoretically be born with two genetic fathers and no ‘mother’. In these recommendations, accepted by the government, the expert group sought to respond to a possible new therapy for some forms of infertility in women caused by abnormal mitochondria which are small energy-producing structures found in every egg.
To alleviate potential mitochondrial diseases, a potential mother could, theoretically, consider creating a child by egg (oocyte) nuclear transfer, a technique similar to that of cloning. This would involve inserting the nucleus of the mother’s egg into a donor egg containing healthy mitochondria, which had previously been emptied of its own nucleus. This egg could then be fertilised in vitro by the sperm of the woman’s partner. The child born in this way would have a set of 46 chromosomes, 23 coming from both its father and mother in the normal way.
Though very little research has yet been carried out to establish if this technique would indeed be successful it is already being considered as an appropriate and possible solution to some forms of infertility. Indeed, this is the reason why an additional clause to the proposed therapeutic cloning legislation was suggested. This clause states, “Research to increase understanding of and development treatments for mitochondrial diseases using the cell nuclear replacement technique in human eggs, which are to be fertilised subsequently by human sperm, should be permitted, subject to the controls in the Human Fertilisation and Embryology Act 1990”.
However, what seems to have been overseen by the report is that it would also be theoretically possible to take the nucleus of a human sperm and put it into an enucleated egg to form a male-egg which could then be fertilised by sperm from another man. Indeed the wording of the proposal would not prohibit such a utilisation of the technique.
This technique would even be possible if the new male-egg was fertilised by sperm from the same man from which the original male-egg was made. In this case, though, one would not obtain a clone since the information on the chromosomes in the sperm hase been shuffled. It could be considered as a form of self-fertilisation or even as incest !
At present, even though some extensive research on mammals has been initiated to see whether such a male-egg would be viable, important biological difficulties still exist. But scientist are optimistic, since the possibility of an egg being made to develop with two sets of chromosomes coming from just the one sex have already been observed in some species of lizards and turkeys in what is called parthenogenesis. In this technique, an egg spontaneously duplicates its single set of chromosomes to form the normal double set of chromosomes found in adult cells. The embryo then develops into a normal animal.
Unfortunately, in mammals the embryos from these virgin births do not fully develop during gestation. Scientist believe that one of the main reasons why problems arise in mammals is the consequence of what they call imprinting, in which the 23 chromosomes of the father and the 23 chromosomes of the mother somehow recognise each other using special marks called imprints. These marks have the effect of letting each set of chromosomes believe that it is incomplete and non-functional without a corresponding set from the opposite sex.
But, because researchers are now beginning to find techniques to strip imprints from certain chromosomes, a successful outcome for the male-egg may eventually be a possibility. The consequences are mind-boggling. Would society accept such motherless children ? Certainly in an age where sex-discrimination is being discouraged, this new prospect would probably be welcomed by some homosexual couples such as Tony Barlow and Barrie Drewitt, the gay couple who made legal history in the UK by fathering surrogate twins. In their case, though, their own sperm was used. They obtained eggs from an American donor to produce “their” embryos. Thus, their children have only one set of chromosomes originating from one of them, the other set coming form the woman donor. On the other hand, the new technique of fertilising male-eggs would enable them to have children “of their own” !
Though no extensive research has yet been undertaken to define the reasons why parents often prefer children “of their own”, the ethical, philosophical and theological issues surrounding the creation of children with two genetic fathers and a surrogate mother are extensive. And they need to be thoroughly thought through before any legislation is considered in parliament. The present recommendations, which were sent to the government in August by the chief medical officer, were meant to adapt the 1990 Embryology Act to the new possibilities brought about by cloning, which was thought to be impossible by most scientist when the law was passed. If the government does not take careful notice to the issues surrounding the male-egg, another report will need to be written by another chief medical officer just because no one believed that this could happen either.
References :
You should be able to find the chief medical officer’s expert group report entitled, “Stem Cell Research : Medical Progress with Responsibility” published in August 2000 on http://www.doh.gov.uk/cegc/
The scientific articles relating to parthenogenesis can be found in the New Scientist magazine http://www.newscientist.com They are :
- The boy whose blood has no father, New Scientist : 7 October 1995
- Like a virgin, New Scientist : 19/26 December 1998 - 2 January 1999
Also look at daily press on :
25th September, Times, page 1, http://www.the-times.co.uk
26th September,
Telegraph, http://www.telegraph.co.uk ,
Guardian, http://www.guardian.co.uk ,
Independent, http://www.independent.co.uk ,
Herald, http://www.theherald.co.uk
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