Material_Manipulacion_Genetica_Embrion

Genetic manipulation and the ethical status of the embryo

Gonzalo Herranz, department of Bioethics, Universidad de Navarra
Lecture at the Universidad de los Andes
Santiago de Chile, 25 August 1993

Index

Introduction: Progress and ethical responsibility

Genetic diagnosis of the pre-implantation embryo

Gene therapy

Some legal rules on embryo gene therapy

A response from medical ethics

Who is the embryo?

The embryo as a product of laboratory

The embryo as a gift

On the term pre-embryo

Conclusion: Human from the beginning

Introduction: Progress and ethical responsibility

The adventure of clinical embryology is just beginning. It already offers us very impressive firsts, but, above all, promises that are very large and difficult to estimate. It is worth giving them serious thought, as they have far-reaching ethical implications.

Manipulations on the young human embryo have been made possible by the confluence of two recently created medical sub-specialties. Firstly, reproductive medicine, or procreation medicine, as some call it. Thanks to it, to advances in the understanding of the mechanisms that are at the physical basis of the transmission of human life, our knowledge of the biology and diseases of the embryo has multiplied. Secondly, medical genetics. Much has been done and will continue to be done by modern genetics, especially molecular genetics, to understand the making of man, to understand how the traits that characterise us are constructed, the advantages and also the weaknesses we inherit, and how genetic errors can be corrected. Genetics is no longer just an explanatory and predictive science: geneticists no longer just diagnose and advise, they will become efficient therapists.

But clinical embryology and medical genetics have not only experienced technical progress: they have also taken on an ethical responsibility, they have become aware of the enormous capacity they have acquired to manipulate man. Like so many other medical specialities, they are at the point where they have to make a fundamental choice: either to serve and respect man, or to dominate him.

For the time being, the opportunities offered by clinical embryology are, for the most part, linked to in vitro fertilisation (IVFET). In the 15 years that have passed since the birth of the first test-tube baby girl, the reproduction of laboratory has become very widespread and commonplace. To produce embryos in vitro today requires a comparatively simple facility and a little skill and experience. Techniques have been simplified to obtain oocytes by ovarian stimulation of the woman, to culture and mature them in vitro, to fertilise them with capacitated sperm and thus produce zygotes, single-cell embryos. The clinical embryologist decides, together with the parents, the fate of these human beings: reimplanting them in the woman's uterus, freezing them to await a new opportunity if the first one fails, offering them to another infertile couple or donating them for research.

Young embryos can also be subjected to various genetic interventions: they can be subjected to diagnostic tests to determine the presence of chromosomal and genetic abnormalities. Once a diagnosis of disease has been established, two divergent courses of action are possible. Destroy the embryo by what Edwards called in vitro abortion, or consider it as a sick human being, who has the right to live with the limitations of the genetic disease and to receive curative or palliative treatment.

In recent years, ingenious techniques have been developed to isolate genes, multiply them in vitro using the DNA polymerase chain reaction, and thus create gene libraries that are of great use for diagnosis and, as is beginning to be envisaged and put into practice, for the eventual correction of an increasing number of diseases.

Moreover, as new technical possibilities for gene transfer, i.e. the inclusion in the genome of cells of a DNA fragment corresponding to a gene, are explored, the possibility of gene therapy is opening up wider and wider. The therapy of gene defects is now a reality, albeit still in its infancy, and is still in its infancy: there is still much to learn before it can be accepted as part of the medical art. Embryonic cells, blastomeres and stem cells from different tissues are revealing fascinating properties in experimental studies, in vitro as well as in vivo. We are gradually learning about the modulating substances that act as growth and differentiation factors and that modify, sometimes surprisingly, the spontaneous behaviour of these cells. Ultimately, this new embryology is so promising and important that it is worth thinking and talking seriously about it.

In doing so, two sets of data and considerations should be taken into account. One concerns the current status of embryo gene diagnosis and therapy. The other comprises the current ethical and legal standards. We cannot make progress on the first if we do not first answer the fundamental question: who or what, from an ethical point of view, the human embryo is.

Genetic diagnosis of the pre-implantation embryo

In principle, it is thought that the application of genetic diagnosis to the in vitro embryo could be done in two types of situations. One is to detect genetic alterations of relatively high incidence, but which occur without a history of genetic disease in the parents or siblings. Another is the case of diseases with known hereditary transmission, where there is an immediate history in the same family. In the first case, therefore, it is a matter of genetic screening, more or less systematically applied to the general population or to those parts of it that are at higher risk; a typical example is the screening for trisomy 21, the determinant of Down's syndrome, which is offered in many countries to pregnant women of advanced age. In the second, to determine which family members are candidates for having, or passing on, the genetic disease.

In both cases, it is possible to carry out a genetic study during gestation, unfortunately often in connection with the removal of the defective embryo authorised by law (eugenic indication abortion). But it is also possible to genetically analyse the embryo before its implantation in the uterine wall. The in vitro phase of IVFET can be used for this, but this involves insurmountable ethical difficulties from the point of view of Catholic morality. One could also examine, in a more technically remote, but much more ethically acceptable alternative, the naturally conceived embryo retrieved from the tube by the tubal lavage technique.

Once the embryo has been obtained, it is possible to diagnose very gross genetic alterations by simple microscopic observation of the zygote. Thus, at the end of fertilisation, three pronuclei can be seen inside the ovular cytoplasm, either because two sperm penetrated it or because the second polar corpuscle was not eliminated. The situation then created is of extreme biological gravity. The development of these triploid eggs (with three haploid chromosome endowments) gives rise to an abnormal development with early death of the embryo.

Attempts have been made by microsurgery to free the triploid embryo from the excess nucleus. The operation requires a great deal of skill and skill, so much so that so far only very few have been able to complete it successfully. Not only because the trauma involved in inserting the micropipette and the aspiration of the excess nucleus is so severe, but also because the correct performance of the operation requires the removal of not just one of the three pronuclei, but specifically one of the two extra ones. A mistake here would have dire consequences, as it would leave the fertilised ovum with two pronuclei of the same origin, the two maternal or the two paternal, and the entities that would develop from them would be Structures tumours (teratomas, in one case, or hydatidiform androgenic molas, in the other). The paternal and maternal pronuclei are somewhat different in appearance and that is an important financial aid , but the error cannot be ruled out with complete certainty. The prospects of this "crude microsurgery" do not look very promising. On the other hand, the problem of triploidy is not very significant in ordinary human reproduction; it is somewhat more so in assisted reproduction, where 5% of oocytes fertilised in vitro have three or more pronuclei. Polyploidy, in general, causes strong and immediate biological disadvantages: one third of polyploid embryos are unable to divide, and those that do, do so with frequent asymmetries that soon ruin their development.

The greatest hopes are currently pinned on the application of genetic diagnostic techniques, through karyotype analysis or the use of gene probes. This will make it possible to distinguish which zygotes are normal and which are affected by a genetic disease. On the one hand, the presence of chromosomal alterations in the zygote is very common. This is not surprising, as chromosomal abnormalities have been found to occur in 35% of unfertilised oocytes (nullisomies and, above all, dysomies, affecting any chromosome). In embryos, the level of chromosomal abnormalities has been estimated at between 23% and 40%. These are errors produced during fertilisation or alterations already present in the gametes and which seem to occur more frequently in cases of infertility, and perhaps linked to advanced maternal age, ovarian hyperstimulation and artificial conditions, a high proportion of the products of fertilisation are a resounding biological failure doomed to die.

The work programme for gene diagnosis of the pre-implantation embryo is more or less as follows: the zygote is cultured in vitro until it develops into an embryo of four, eight or more cells. The pellucid membrane is then pierced with the financial aid of a cutting micropipette or by applying acid Tyrode's solution (this should not be used on the human embryo, as it is too aggressive), and one or more blastomeres are removed by aspiration, extrusion, or mechanical cleavage. The procedure itself requires an extraordinary skill of micromanipulation. If the embryo is already in the blastocyst stage, a group of cytotrophoblast cells, which will form the placenta, not the body of the embryo, can be excised or herniated through the pellucida, although the embryo may no longer implant. If the diagnostic technique requires some time, it is necessary to freeze the embryo at a very low temperature ( leave ) for the necessary time. Often, it is desirable to culture the extracted cells, as it is easier and safer to work with as many cells as possible. Karyotypes can be obtained to detect chromosomal abnormalities, or hybridisation studies using in situ gene probes, the efficient DNA-polymerase chain reaction technique can be applied.

As these pre-implantation genetic diagnosis techniques are applied today, they can be considered as a screening system: if the embryo fulfils requirements of normality/acceptability (it is possible, through pre-implantation genetic diagnosis, to determine, among other things, the sex of the embryo, whether it will be a girl or a boy), the acceptable embryos are transferred into the uterus. Those that do not comply with requirements are deprived of the opportunity to develop. Unfortunately, the diagnosis of chromosomal or genetic abnormalities is linked in today's medical practice to what Edwards, the pioneer of in vitro fertilisation, called in vitro abortion.

Gene therapy

And why not cure it? Therapeutics for diseases of the zygote or the young embryo are not yet developed, but in general, the ideas on topic are not on the right track.

Things are at a very early stage, as I showed when discussing the treatment of triploidy and the high cost in embryonic lives of diagnostic procedures. Recall that the simple act of freezing-thawing intact, non-biopsied embryos leads to the death of just over half of them. Preimplantation embryo therapy is project deferred to the distant future. Moreover, it could be said that the idea of genetically treating the embryo is actually forbidden.

In the scientific community and in society there is now almost universal consensus on one point: that gene therapy of somatic cells, to which there are no particular ethical objections, and the genetic modification of germ cells (gametes, zygotes and young embryos), which is either prohibited by law or subject to an indefinite moratorium, are considered to be two completely different areas. This is the case both in the ethical guidelines of scientific institutions and medical organisations, as well as in the laws passed to that effect. Behind this consensus is both the fear that attempts at gene therapy may be accompanied by harm transmissible to offspring, which is a prudent and reasonable fear, and the rejection of the possibility that gene therapy could be used as a tool for such things as race improvement, the production of supermen or the like. It is repeatedly stated that the question of gene therapy of the embryo or germ cells cannot ethically be addressed until extensive and satisfactory experience has been gained with the genetic manipulation of somatic cells.

This gives us a long time to mature the answer to the fundamental question: should the embryo be treated medically as one of us? Is it a human being of our own rank or, on the contrary, is it an inferior being that can be treated differently? What is, in fact, the ethical rank of the human embryo? What do people think of it, of its nature, of its rights? The content and energy with which different attitudes towards the ethical status of the human embryo are expressed cover a very wide spectrum, translating from different ideas about how to become human, or what it means to be human, from religious and cultural traditions about the respect due to nascent human life, from the acceptance or rejection of impairment, from the relaxation, introduced by the decriminalisation of abortion, of the collective conscience towards the value of human life.

Some legal rules on embryo gene therapy

Let us first consider the influential legal point of view. There is no shortage of documents on topic. Thus, the European Parliament resolution A 2-327/88, on the ethical and legal problems of genetic manipulation, resolves, in relation to genetic engineering interventions on the human germ line, that all experiments seeking to modify arbitrarily the genetic programme of human beings should be prohibited; that criminal sanctions should be imposed on those who transfer genes into human gametes; that a definition of the legal status of the human embryo should be agreed upon, guaranteeing the precise safeguarding of its identity; to agree on a definition of the legal status of the human embryo that guarantees the precise safeguarding of its genetic identity; and to establish by law that any partial modification of the hereditary heritage constitutes a falsification of human identity, which is inadmissible and unjustifiable insofar as it is a highly personal legal asset. The European Parliament does not make a distinction between therapeutic intervention and enhancement manipulation, i.e. between curing the sick and creating gifted individuals.

The prohibition of any genetic intervention on human embryos is particularly strong in German law. This is also the case in the Guidelines of the Danish Ethics committee on the protection of human gametes, fertilised eggs, embryos and foetuses, which state, among their prohibitions, that "genetic experiments and gene therapy on human gametes, zygotes and embryos, as well as any other gene therapy subject , resulting in genetic changes that can be passed on to future generations" are prohibited.

The American Fertility Society Ethics Committee's Ethical Considerations on New Reproductive Technologies takes a middle ground position, which has already begun to evolve following President Clinton's repeal of the Reagan-Bush era restrictions. The only barrier to experimentation on human embryos will be the fear that these experiments will result in harmed subjects who may eventually sue those who harmed them or tolerated their birth with them (wrongful life). Other bodies, such as the American Academy of Paediatrics, oppose any ban that would limit the development of gene therapy in humans.

As far as Spain is concerned, Law 35/1988, on Assisted Reproduction, is moderately permissive: it establishes in its article 15, 2, that research on viable in vitro pre-embryos will only be authorised: a) if it is applied research of a diagnostic nature, and for therapeutic or preventive purposes. b) if the non-pathological genetic heritage is not modified. This implies that interventions that seek to medically benefit the embryo, if they act on its abnormal genes, are tolerated. But curiously, the same law completely separates the rules on diagnosis and treatment from those that apply to research and experimentation, and creates difficulties that seem to me insurmountable in applying experimental findings to human clinical practice. It prohibits, for example, gametes used in research or experimentation from being used to produce pre-embryos for procreation (Art. 14.3); and gametes or pre-embryos from being transferred into the uterus without the required biological or viability guarantees (Art. 20.2Bi). This seems to drastically limit the therapeutic application of experimental findings. The results of animal or in vitro experiments cannot be reliably predicted by result when applied to human patients. These are unknown before they are tested on human subjects. Any assumptions are uncertain. At some point it will be necessary to make the leap and apply the results achieved in the experimental laboratory in the human clinic, in patients. This is one of the many incongruities of Law 35/1988. And it is not strange: it was the first state-level assisted reproduction law in the world and it is grade that it is a "first generation" product.

Faced with this legal situation, what do doctors think, and what ethical rules are in force?

A response from medical ethics

In Spain, we have a situation that is in theory correct. Article 25.2 of the current Code of Ethics and Medical Deontology of the Spanish Medical Association reads as follows: A sick embryofetal human being should be treated agreement with the same ethical guidelines, including the informed consent of the progenitors, that inspire the diagnosis, prevention, therapy and research applied to other patients. By regulating in this article the doctor's relationship with his embryo-fetal patient, the Code assigns to the doctor the role of protector of the life that is beginning, while extending to the embryo and foetus the ethical prerogatives that medicine recognises for all human beings.

The continuity of human life imposes a continuity of ethical respect and of the medical attendance , with its diagnostic, preventive and therapeutic services. The nascent embryo-fetal medicine is a medical specialization program conditioned by the peculiar characteristics of biology and pathology in the different ages of man. It therefore has the same raison d'être as Neonatology, Paediatrics or Geriatrics, and obeys the ethical rules common to all medicine. Its interventions are guided by the same criteria of efficiency and tolerable risk. Just as in postnatal medicine a policy of eliminating lives of little value is not tolerable, in prenatal medicine genetic screening or the systematic destruction of embryos or foetuses that are diseased or simply excessive in number, as practised in so-called "selective reduction", is not tolerable. If a human being is sick before birth, he or she must benefit from medical progress: many diseases can already be diagnosed and treated. Therefore, in today's medicine, the embryo, like the foetus, must be considered as just another patient. It is not a biological object of inferior status that can be discarded in good conscience. The human embryo is open to all scientific initiatives, on condition that it is respected. The moratorium on genetic interventions on germ cells has a character provisional, it is conditioned by the rudimentary nature of our technology. It cannot be a permanent decision, expressive of the embryo's lack of ethical values. It would be an ethical absurdity to prevent the application of germ line gene therapy which, respectful of nascent life and the dignity of procreation, would cure the embryo, freeing it and all its offspring from the genetic error it has inherited from its parents.

Embryo-Fetal Medicine realises the true purpose of medicine. It is a genuinely medical and ethical specialization program . On the contrary, abortion as a treatment of embryofetal disease, of genetic error, is not. Embryofetal medicine is born from the alliance between medical respect for the weak and biomedical research. Abortion is based on the discriminatory idea that there are inferior human beings who can be discarded.

The Spanish deontological rule is one answer among many to the fundamental question about

Who is the embryo?

One of the most significant battles in bioethics today is being fought over this question. It is curious. These tiny human beings, who were practically unheard of until a few years ago, have acquired a symbolic value. They have gone from being in an inaccessible limbo to occupying a central place in the ethical discussion. There is reason to suspect that to a large extent the fate of humanity will be strongly determined by the answer to the question of whether the human embryo is a thing, a man or an intermediate entity yet to be defined. The notion that ultimately prevails will set the moral tone of the society of the future. It will ultimately determine inter-human relations.

The embryo as a product of laboratory

If one were to ask experts in clinical embryology today at survey what an embryo is, or who it is, and what moral demands the embryo makes on us, most experts would answer with the familiar "Don't know, no answer". For many it is not clear what, or who, an embryo is.

This ignorance is a recent phenomenon. Because until the advent of IVFET, any book on human embryology began more or less as follows: "The development of a human individual begins with fertilisation, a phenomenon whereby two highly specialised cells, the spermatozoon of the male and the oocyte of the female, unite and give rise to a new organism, the zygote". But today, with the introduction of in vitro fertilisation, this no longer seems to be the case. It seems as if the direct visual observation of the ever surprising phenomenon of fertilisation produces opposite effects among scientists. For some, it brings a lasting smile of amazement to observe the mysterious simplicity with which a new man is begotten. To others it causes a kind of incredulous disillusionment, as if they would not accept such a humble genesis for man.

The reason is not biological, but political tactics. Only by depriving the embryo of its human character, can the huge loss of embryos through in vitro fertilisation be ethically neutralised. It is in the interest of in vitro fertilisers to claim that the zygote is irrelevant, a molecular product devoid of human form and value. They insist that fertilisation is a relatively banal moment, without the significance and transcendence that others attribute to it. I cannot resist referring to what R. G. Edwards says in defence of this view:

"Embryo research raises the question about the fundamental rights of the human embryo, issues such as when life begins, or whether embryos have any rights at all. The embryos we are talking about are tiny: thousands of them could fit into the volume of a single drop. They are tiny clumps of cells; they have no hands, feet, or head. They change shape, but under no circumstances do they bear the slightest resemblance to a human being until seven weeks of gestation. And yet there is a crying ethical question surrounding these tiny specks of life, questions where the opportunities to do good conflict with the value placed on incipient life.

Some people object to work on human embryos because they believe that life begins at fertilisation. Those who think this way claim to be fundamentally mistaken, because they oppose studies on in vitro fertilisation and its applications. They use the absolutist argument that with fertilisation the embryo receives all human rights. They say that the embryo is equivalent to a child or an adult, and that destroying embryos in research is the same as killing adults. I," Edwards continues, "cannot share this view. The biological facts lead to widely divergent moral conclusions. Life is a continuum: it does not begin at any particular moment. As alive as the embryo is the sperm and oocyte that gave rise to it. The genetic originality and unrepeatability of the sperm and oocyte is no less that of the new embryo; after all, it is borrowed from its precursor cells, which are cells without special ethical requirements. There are no reference points between which a line can be drawn between life and non-life. There are too many arguments and exceptions to accept that fertilisation is the beginning of life.

Absolutists say that at fertilisation a unique genetic character is established, that the oocyte is then activated in a unique way. But none of this is true.

Edwards then refers to how many children with Down's syndrome present a mixture, a mosaic, of normal and trisomic cells, whose mutual proportion is constantly changing; how a fertilisation can give rise to a hydatidiform mole, which is not a human being at all; how a parthenogenetic development is possible, without fertilisation, which in some animal species reaches a very advanced Degree of development . And returning to more beaten paths, he wonders how fertilisation can be the beginning of life if we know that some embryos can fuse and form genetic chimeras or that an embryo can split days after fertilisation to give rise to two or more identical twins; or that a high proportion of the products of fertilisation are a resounding biological failure condemned to die. He concludes:

"Fertilisation is merely one stage, one stage in a long, complex and continuous process, so choosing it as the beginning of life is as arbitrary as choosing any other. Fertilisation is only one step in the development of a person. The oocyte gradually develops into an embryo, and any line to mark when the embryo's rights begin is arbitrary. For my part, I would suggest that the period from 12 to 30 days after fertilisation is a time worth studying, as this is when nerve tissue begins to form.

In contrast to the "conceptionist" point of view of classical Embryology - one is human from the very first moment - the "developmentalist" view became very strongly consolidated, following the publication of the influential report of the Warnock Committee. The decisive influence of this report on public opinion is based on its agnostic character, in having made the humanity of the embryo a taboo which it has refused to answer. It has deliberately limited itself to issuing administrative rules, refusing to enter into metaphysical discussions. The confrontation within the Committee between those who considered the human embryo as a being to be fully respected in its humanity and those who had an evolutionary idea of the progressive acquisition of rights and the credit to respect, traits that are acquired from a pre-human starting point, brought the Committee to the brink of rupture. To defuse the situation, Baroness Warnock offered the solution of setting 14 days post-fertilisation as the period within which destructive embryo research could be authorised, which, astonishingly, was accepted by both sides. Then came the creation of the term pre-embryo, which has been so successful, and the need to seek arguments to give some biological validity to this administrative period of 14 days, the date on which the period of lack of human rights and ethical relevance ends. Today, without anyone having provided substantial data in its favour, the myth of the 14-day period has become a dogma that has crept into science. It has been imposed not because it is in itself significant of any biological reality, but because it serves to validate qualification or ethically neutralise the deliberate loss or destruction of embryos that inevitably goes hand in hand with assisted reproduction procedures, research on embryos, abortive contraception and counter-management. The notion of the pre-embryo stripped of dignity and human rights has been a kind of plenary indulgence for the dark side of medical interventions on human reproduction.

After Warnock, a pact has been reached among "educated" people to no longer talk about topic. What forms the current "orthodoxy" is to ignore the ontological consistency of the embryo and to regard it as a functional notion. The early human embryo, in the "official" version, has become an ethically neutral entity, so that our relations with it have no moral significance. The manipulation and destruction of young human embryos need not concern the law, as long as such operations are carried out with the authorisation of an administrative control body.

The embryo as a gift

In contrast to the utilitarian warnockian doctrine of the embryo-thing, the Vatican Instruction Donum vitae imposes respect as an ethical attitude towards nascent human life, towards the embryo-man. According to Donum vitae, all human beings are to be loved equally and all are to be respected as human persons from the moment of conception. Wherever conception takes place - in places as morally disparate as within marriage or outside it, in the aggressive injustice of rape or in the aseptic conditions of the tube essay- conception always inaugurates a human life, which is not that of the father or the mother, but that of a human being who develops by himself and who would never become human if he were not already human at his very biological beginning. The embryo is ethically an equal to us. If it is ill, we must treat it according to the best and most beneficial advances in biomedical science, that is, diagnose it and apply the appropriate therapies, always respecting its personal uniqueness. Prenatal diagnosis and therapeutic interventions on the human embryo are licit if they respect its life and integrity, if they seek its cure and well-being.

The Instruction Donum vitae uses very simple, respectful and compassionate language and, contrary to what many have reproached it for, it is open to scientific daring and modernity. It does not volatilise the embryo or plunge it into a stratum of subhumanity. On the contrary, it confers full rights on the embryo and makes it share in all the ethical requirements conferred on human beings. The human embryo is not regarded as an experimental animal or a cellular complex, but shares the privileges of other human beings.

This very encouraging and positive doctrine of the Vatican Instruction has been the subject of much scorn or unjust silence, while report Warnock has been given flattering and gratuitous propaganda. But I will not tire of insisting that, amidst the exuberant proliferation of guidelines and recommendations on human embryo experimentation, only Donum vitae is maximally open and consistent. Apart from it, no other has shown fidelity to the Declaration of Helsinki. The Vatican Instruction endorses the idea that the interests of science or society can never prevail over those of the individual, including the embryonic individual; it points out that research cannot become a destructive manipulation of human beings; it advocates the free and voluntary consent of the subjects of experimentation.

On the term pre-embryo

It is worthwhile, before concluding, to consider for a moment the validity of the term pre-embryo. It is a misleading word by means of which secularist ethics seeks to escape many moral problems. It was not introduced to designate a biological reality, but to evaporate a moral responsibility. It is not for nothing that the originator of the term, Dr. Penelope Leach, is a psychologist. The Lancet, in an article publishing house, stated that "it is appropriate to use the less emotionally charged term pre-embryo for the product of conception in its first 14 days.... The term pre-embryo has done more than anything else to lower the temperature of discussions around embryo research". But I think that if there is one thing the discussion around the ethical status of the human embryo needs, it is a little warmth.

The word pre-embryo is a semantic trick to expropriate the embryo not only of its human condition, but also of its biological entity. It is also an effective dialectical weapon, which serves to impose silence on those who dissent from the official point of view. Let us look at an eloquent example, which reveals the 'fair play' with which, at times, discussions are held in scientistic cenacles.

In the Symposium "Human Embryo Research. Yes or No?", published by the Ciba Foundation, transcribes a discussion on Embryo or Pre-embryo? It is a demonstration of how opposition to the use of the word is literally ignored. I reproduce part of the dialogue, in which, in addition to moderator, Sir Cecil Clothier, several leading figures intervene: Robert Edwards, the pioneer of FIVET, Anne McLaren, a committed embryologist, and John Maddox, publisher of the journal Nature.

Sir Cecil Clothier opens the dialogue: "It would be interesting to know what you think of the... expression pre-embryo".

Maddox: "I think it's a cosmetic trick".

There follows a brief but confusing discussion in which Anne McLaren, Robert Edwards, and John Maddox express different views on the ambiguity with which scientists and the public use the term embryo, on the questionable acceptability of the term pre-embryo, on the sufficiency of the vocabulary of classical Embryology to designate the different phases of development. Not a single word is said in favour of the term or on the legitimacy of its use in biology. However, Sir Cecil imposes the official orthodoxy when, to close the discussion, he pontificates: "We all think that 'pre-embryo' clarifies the problems".

The term pre-embryo does not clarify, but suppresses the problems. The term pre-embryo is a typical product of scientistic ideology, a materialistic ideology characterised by deliberately ignoring an important part of reality. This is a tactic tenaciously employed to eliminate all reference to the extra-scientific strata by those who want to establish the rule of science in the world. Chesterton said of the language that some men of science create and use, when confronted with vulgar but highly complicated realities, such as first love or the fear of death, that they overcome the difficulty by reducing these realities to their easiest aspect. And so they will call first love the sexual instinct, and fear of death the instinct of self-preservation. And Chesterton adds: That there is a strong physiological element in both the youthful idyll and the memento mori, makes them, if possible, more disconcerting than if they were purely intellectual facts. Precisely because these realities are animal, but not entirely so, the difficulties are accentuated. Materialists analyse the easy part, keep silent about the hard part, and go off to tea.

Conclusion: Human from the beginning

This is what the notion and term pre-embryo has done. To remain with the visual appearance of the young human embryo and renounce to see its deep reality. It is with that humble appearance that each of us begins our own existence. Our biography has this minimal and, at the same time, glorious beginning. No one becomes a man without starting there. If those 14 days of non-human existence were abolished, no one would become a man. Among other things, because it is in those days that the human embryo makes the most important biological decisions. Through urgent biochemical messages, it changes the physiology of the maternal organism, which is fully at its service. We have all been single-celled embryos and, having been so, we have become capable of being what we are now. To deny embryos the right to humanity is a cruel injustice, it is to deny ourselves our human origin.

Said the classic: I am human and I do not renounce anything human. I cannot give up those 14 days, I cannot admit that during their course I had no importance, that it was a discretionary and arbitrary matter, a matter of indifference to let me live or to destroy me.

Every human being is engendered in the guise of a cell. On the day this happens, the highest concentration of humanity per unit volume is reached, because it is the day on which God creates him in his own image and likeness: a single-celled, microscopic image for the moment, but full of power and meaning.

What happens in the early days of our life, what happens in nascent life, is to stagger one's mind. Lewis Thomas has said it with inimitable grace. "You start from a single cell that comes from the fusion of a sperm and an oocyte. The cell divides into two, then four, then eight, and so on. And, very soon, at a certain point, it turns out that among them there is one that is going to be the precursor of the human brain. The mere existence of that cell is the first of the wonders of the world. As long as it was awake, people should be commenting on that fact. They should be calling each other all day long, in endless amazement, to talk about that cell alone. It is an incredible thing, but there it is, perched in its place in every one of the billions of human embryos in all of history, from every part of the world, as if it were the easiest and most ordinary thing in life.

If you want to live from surprise to surprise, here is the source of them all. One cell is differentiated to produce the massive apparatus of trillions of cells, to think, to imagine, and also, for that matter, to stay in one piece in the face of such a formidable surprise. All the information necessary to learn to read and write, to play the piano, to argue before a committee of congress, to cross the street in traffic, or to perform that wonderfully human act of stretching out one's arm and leaning against a tree: all that is contained in that first cell. It contains all the grammar, all the syntax, all the arithmetic, all the music.

It is not known how this differentiation takes place. At the very beginning of the embryo, when it is nothing more than a pile of cells, it seems that all this information and much more is latent in each of its cells. When the stem cell of the brain appears, what is going to determine the brain is connected, and, at the same time, all the other potentialities are disconnected, so that this cell can no longer choose, as its precursors could, to become a thyroid cell or a liver cell, or anything else. It can only be a brain.

Nobody has the faintest idea how it is done, but the truth is that nothing in this world is more interesting. If, before I die," concludes Lewis Thomas, "someone finds the explanation, I'd do something crazy: I'd hire one of those planes that can write in the sky, a whole squadron of them, and send them around the world writing one exclamation mark after another, until the money runs out.

I believe that it is with this enthusiasm for life that we must deal with the biology and ethics of the human embryo. Ten years of reading arguments in favour of the Warnokian thesis have not convinced me that it was not I, with all my rights and all my destiny, who began to live the day my parents begot me, the day God made me in his image and likeness: a single-celled, microscopic, but meaningful image.

Thank you very much.

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