Biological Ethics
Table of contents
Chapter 22. Manipulation of the human gene pool for eugenic purposes.
N. López Moratalla and A. Ruiz Retegui
a) Introduction
Advances in the technology known as "engineering Genetics" have attracted the attention of some scientists who have seen in it the possibility of "creating" new species through gene transfer, or the modification of gene control systems, both in animal or human gametes and in the zygote and cells in the early stages of the embryo development . Some seek to improve human biology by intervening directly in the human gene pool, modifying the programme, not just seeking a higher frequency of favourable alleles. The new technology involves overcoming biological frontiers that seemed to set insurmountable limits to human action.
This is one of the areas where the dynamics of scientific progress is most clearly manifested: it is not just a matter of actively intervening to "put in order" what has been altered, but of considering nature - man's genetic heritage in this case - as a neutral field of action, materials with no meaning of their own from which any product can be "manufactured". From the outset, this approach had a domineering character. We still remember," says Rodríguez Villanueva1 , "the worldwide impact caused by the publication of a special issue of Time magazine issue graduate "The New Genetics: Man into Superman" at the beginning of the 1970s. Reading some paragraphs of its articles, one was somewhat shocked by the possibility that several of the facts described could simply come true. Among other sentences were: "Now, only 35,000 years after the birth of modern man, research is moving in a new and much more dramatic direction. Man has not only begun to discover the most fundamental processes of life, but will soon be able to manipulate and even alter them, curing diseases such as cancer, correcting genetic defects that possibly account for 50% of all human ailments, reducing the ravages of old age, extending the prowess of his intelligence and his body. For the first time in the history of the planet, a creature will be able to understand its origin and will be able to try to design its future".
At the present stage of research - see the previous chapter - the possibility of achieving major modifications in the sense of endowing an individual with new functions that are totally foreign to its species does not seem to be within reach. issue As is well known, changes to the genetic message require not only the introduction of a large number of genes, but also the perfect coordination of their expression, and this, from a technical and practical point of view, does not seem to be easily achievable, at least for the time being. However, the manipulation of another subject of characteristics, given by the expression of a single gene or the modification of some control system, does not seem particularly difficult.
It is true that the efforts in this area are primarily aimed at correcting a defect (therapy Genetics) by replacing the affected gene. But it should not be forgotten that the same technology that attempts to alleviate Down's syndrome is in essence what is required to programme a "superman" or a "microman"; manipulation Genetics for eugenic purposes is beginning to cease to be a science-fiction topic and is starting to penetrate laboratories.
It is interesting to insist on the fact that this manipulation is essentially different from the possible and desirable therapeutic intervention in the genome to cure a disease Genetics, which would not represent a change in its endowment but simply the repair of a defect that prevents that person from exercising his or her own physiological functions normally. And it is also totally different from that which limits itself to selecting only certain individuals, considered biologically better, to transmit life; we have referred to both in the previous chapters. The new eugenics aims at programming different men.
Would it be ethically acceptable to intervene on the genetic heritage, going beyond the limits of mere therapy, i.e. changing an altered gene for another one that is the same, but in perfect condition? Are there ethical limits to the new eugenics? It is obvious that the lawfulness of interventions on the genetic heritage, for eugenic purposes, requires that human dignity be respected, taking into account aspects such as: identity staff; the fact that all men share a common biological nature; and the fact that people, because they belong to one race or another, are not superior or inferior2 ; the dignity of man does not lie in a better or worse biology. The orientation for the use or refusal of the use of these technologies will therefore have to be found in the understanding and deepening of the natural meaning of the genetic heritage.
b) Identity staff
The human person is absolutely unique and singular, unrepeatable, with a perfect unity of spirit and body. That body reveals man, it is a human body; through the body, man distinguishes himself from all other animals and separates himself from them; and, in turn, each human body expresses that particular person. Therefore, the biological nature of man, the endowment Genetics contains the message that constitutes a human body, which is intangible, as it is constitutive of the identity staff of the individual throughout his life. Respecting human dignity therefore means safeguarding this human identity.
The biological basis of this unrepeatable individuality lies precisely in the process by which a new life originates. As Jérôme Lejeune3 comments, "recognising a friend among a multitude of faces means observing that all men have the same nature, even if each of them is unique. The reason for this phenomenon is the propagation of the species through the father and the mother (...). The conjugation of two compatible but different parental cells gives each offspring a unique combination. Both the species and the individual benefit from this. The individual finds its biological personality and the species receives a diversity that allows it to adapt.
The ethical principle, which requires the preservation of identity, primarily concerns the manipulation of the zygote - where the new individual is already constituted - or of the first embryonic cells. issue In the course of the establishment of abortion laws and the spread of contraceptive techniques, or in order to avoid responsibility for the high number of deaths of children in the early embryo stage through "in vitro" fertilisation and the desire to legitimise research and experimentation with these embryos, voices have been raised which, without any scientific basis, try to defend that the individuality of the embryo does not occur until nidation; For them, this would mean that the life of a human being does not really begin before this phase and not with fertilisation, as clearly established by biology, since it is at this moment that the genetic programme is constituted. For the defenders of this idea, in these early stages of the embryonic development before nidation, one could not speak of a human being, but would have to consider the morula simply as a conglomerate of human cells without its own identity. They are based on the fact that sometimes, in the case of twin pregnancies, one fertilised ovum gives rise to more than one individual, and that sometimes, extraordinarily, an embryo is produced by the fusion of two embryos before the end of nidation.
The criteria of unity -impossibility of dividing- and uniqueness -impossibility of fusing-, with the ease of defining the individual, are new in biology, as A. del Amo points out (oral communication); twinning, the possibility of the zygote or early human embryo dividing to give rise to a pair of monozygotic twins, has never been an obstacle to considering the zygote as an individual. In some animals, both lower and higher, vegetative multiplication takes place in the early embryonic stages (proembryony).
The constitution of the gene pool as an expression of their individuality
Biological science has demonstrated with sufficient rigour that the fertilisation of the ovum irreversibly determines the individual - with all the characteristics proper to the species expressed in the concretisation of that individual - by establishing the endowment Genetics - unique and unrepeatable - that the zygote cell carries, from which that living being will develop; there is already what will make it a member of that species and what is individual and specific that will make it that specific individual.
The genetic heritage - already complete at conception - contains the precise instructions for the various tissues and organs to be formed, and also contains the guide to end its life once the species-specific lifespan limit has been reached.
The development of each living being is a continuous process, with stages that follow one after the other in a rigorous and precise order, all of which are necessary for the normality and integrity of its functions. Despite the multiple stages of this development , each individual's Genetics endowment is maintained in each of its cells and throughout life. Thus, although the material elements that constitute the body undergo change, one can properly speak of a biological identity of each living individual from conception to death. This makes the identity of living beings far superior to that of other elements in the world, and, of course, essentially different from that of artefacts.
Individuality, with the unity it implies, is biologically traceable throughout the organism's development from the first divisions of the zygote. During the first stages of the embryonic development the cells, which originate by successive divisions of the zygote, are more or less equivalent to each other; when the embryo has reached issue of 16 cells, some differences begin to be distinguished between them. However, this does not mean that there is a multiplication of identity, or that identity becomes diffuse or elusive. Indeed, the cells that result from the division of the zygote are not simply a collection of cells exactly like each other and like the one that formed the zygote, each endowed with the same individuality as the zygote. Although they may separate, when they are united, they constitute a single biological reality, forming a very elementary bicellular or tetracellular organism. This group of cells constitutes a true unit thanks to the appearance of a specific protein located in the membrane, the F9 protein, a sort of "glue" that not only holds them together, but also "informs" each cell of the presence of the others, establishing a precise connection and interaction between them, and ordering them in the morula phase while the issue of the cells goes from 32 to approximately 100. The F9 protein is the biological element that allows us to affirm that the morula is not an undifferentiated set of very similar cells but a truly articulated unit. The signal for the elaboration of this protein is linked to the process of fertilisation itself, and is possibly the first instruction issued by the newly constituted genetic programme. The F9 protein that unites the cells born of the zygote divisions into a unit is not present in the gametes of the parents, nor in the zygote, nor is it present in any of the cells after the morula period has passed. Pathologically it can reappear in one of the malignant tumour cell types teratocarcinoma. Similarly, another antigen, SSEA (specific embryonic state antigen), instructs the cells of the morula to leave the internal cavity that will turn it into a blastocyst.
Twinning: In the human species - as in many others - when the genetic programme is just beginning, i.e. in the first few days, vegetative multiplication is possible, which is not typical of mammals, but is the normal form of reproduction in other species. The cells present in this period then separate into two morulae, which will give rise to monozygotic twins. If the division were not complete, Siamese twins would be born. The possibility of such multiplication is no more a valid argument against the individual character of the zygote or morula than it is a lack of organic unity for a bacterium to reproduce by cleavage, or for the starfish, for example, as an adult, to split and give rise to a new individual from each half.
Moreover, the ability of morula cells to divide into several cells depends on the interactions established through the membrane protein F9, the appearance, disappearance and quantity of which is genetically controlled by the embryo. Experimentally, it has been shown that if the link established by this protein between the cells of the morula is artificially broken - through the addition of a specific antibody against this protein - it disintegrates when the cells separate4. It could therefore even be argued that the case of twinning is not a random accident, but established in the endowment Genetics that will control the disposition and quantity of F9. This would not mean that in the single zygote with that endowment Genetics there are two individuals, but that this single individual is facilitated or allowed by its endowment Genetics to multiply vegetatively. The cells that separate in this division cannot give rise to parts of the organism - as occurs in some species with mosaic biogenesis - but to another organism - which then begins to live - whose development would be directed by the same genetic programme constituted at the fertilisation of the ovum, with identical biological characteristics and with the same progenitors.
Embryo fusion - Very infrequently, an embryo fusion of heterozygous siblings may occur in the first few days. The death of one of them takes place when its cells, that is to say, its entire body, is incorporated by the other in a kind of transplant that will cause the recipient to later manifest in the regions of its body derived from the incorporated cells, the characteristics of its sibling. The case would be similar to that of a kidney transplant, which continues to manifest the immunological characteristics of the donor.
Despite the magnitude of the change involved in embryo fusion, it does not argue against the unity of the morula, although when it takes place, the unity of the morula is weakened. Just as the unity of the body into which a heart has been transplanted is weakened.
Thus, an individual of any species has its own unrepeatable identity as soon as its genetic programme is established, a genetic programme that may in some cases go through a phase of vegetative multiplication and even fusion with another dead embryo.
Identity and continuity: To affirm that individuation is achieved with nidation hides, in addition to the biological fallacy we have seen, that of confusing identity with continuity. If necessarily, as Inciarte5 points out, identity, the fact that two things are the same, meant that in each of the instants of their existence both have the same properties and that in all the instants of their existence both have all the properties, then identity would mean that no change is possible. This identity - which is not the same as continuity - is maintained throughout all the changes that occur in the embryonic development and throughout the life of the individual. And those changes could include - in rare cases - twin division or even fusion.
The human gene pool as a biological expression of individuality staff
As already stated, the ultimate foundation of human dignity lies in the fact that in the concrete origin of each person there is, along with the generation by the parents, a creative action of the individual soul on the part of God; this implies that the begetting parents and God the creator of the soul are not two separate causes having different effects, but true con-causes constituting a single principle of the person. This means primarily that the begetting parents are truly and properly partakers of God's creative power. "But it also means6 that between the creative call of God, the foundation of the absolute dignity of the person, and the bodily disposition there is a biunivocal correspondence. Indeed, the individuality of the creative call is expressed in the concrete disposition of the body, and therefore it is to be expected that the uniqueness staff is also expressed biologically. The expression of the uniqueness staff within the specific community with the other "individuals of the human species" is the endowment Genetics, unique and singular for each person. The genetic heritage is like the material precipitation - and as such researchable by positive science - of the ordering and integrating function of the soul as substantial form: like the substantial form, the genetic heritage is also present in each of the somatic cells, "marking" each part of the body as part of a single whole that expresses itself in this complete heritage, even if in each part it only configures the corresponding organ or cells.
Thus the identity staff, whose foundation lies in the singular call from God and whose formal expression is the spiritual soul, has its biological expression precisely in the genetic heritage. It could be said that the genetic heritage is the "organ" of the identity staff. In its correspondence with the identity staff lies the importance of the not only biological, but also anthropological - and therefore ethical - significance of the genetic heritage, because it implies that through it the identity can be genetically manipulated.
That the human person can be manipulated on account of corporeality is self-evident. The protection of the absolute dignity of the human person against this danger is expressed as a moral requirement in the 5th commandment of the Decalogue. But the possibility of manipulation and thus the scope of this precept has been extended by the development of manipulation techniques Genetics. Even if in fact the possibilities of manipulation are currently rather limited, it is necessary to remember that manipulating the genetic code is not an indifferent manipulation of the "material" of the cosmos, but a manipulation of the identity staff7. The 5th precept of the Decalogue acquires a new scope for the scientist's conscience: "respecting the dignity of man implies safeguarding that identity"8. 8 Therefore, the dignity of the person prohibits the manipulation of his genetic heritage, which, as biology shows, is established at the moment of conception, when the nuclei of the gametes of the progenitors fuse".
(c) Common biological nature of mankind
As far as the manipulation of germ cells with a view to improving the genetic heritage of subsequent generations is concerned, the problem of changing identity does not arise, since the identity of a person who does not yet exist cannot be manipulated.
However, it should be borne in mind that it could constitute an attack on human dignity if, by modifying the common genetic heritage of mankind, different groups of people - a new species of people - were to be produced, between which a reproductive barrier would be established.
Procreation, the origin of a new human life, is linked to the biological union and staff of the parents. Biologically preventing procreation, in addition to being an attack on the origin of each new life, means creating a marginalisation of some people in relation to others.
d) Racism and the Superman
A third aspect to take into account, as a fundamental criterion for making appropriate decisions in this field of human experimentation and manipulation, would be that this search does not stem from a racist and materialistic mentality, in which improvement means exclusively biological improvement. A racist mentality that has wanted to be "scientifically based" on Darwin's theories.
Biology clearly establishes that it is absurd to attempt to classify groups of men - races - as better or worse, superior or inferior, according to their biological conditions. Races are now defined not so much on the basis of apparent characters as on the basis of the genes which govern those characters. The frequency with which these various genes are present in a group constitutes the structure Genetics of that group. Thus the definition of breeds consists of grouping populations with small genetic distances, and classifying them into two different breeds if the genetic distances are greater. The human species resists this subject of classifications: the genetic variability is very large, so that, as Lewontin9 has shown, the distance Genetics average between people from two different countries is 7 to 8%; and the maximum distance between those belonging to two different races is only 15%.
Man's freedom both to move throughout the world and to establish a relationship staff and procreation over and above different external characteristics has produced such genetic variability that races in the human species do not correspond to any objectively and stably definable reality.
Even less well founded is the attempt to rank men according to their biology and to think of a "superman", a consequence of the decision of scientists to take the course of evolution into their own hands and to improve, in some way, certain general qualities. The idea of a taller, longer-lived person, etc., is too poor to constitute an ideal of man, to which to sacrifice his dignity; and, on the other hand, the subject of personal characteristics, intelligence, goodness, etc., are values that escape genetic determinism. Any attempt to take things in this direction would be tantamount to the temptation to introduce a new form of totalitarianism.
"The manipulation Genetics becomes arbitrary and unjust when it reduces life to an object, when it forgets that it deals with a human subject capable of intelligence and freedom, respectable in spite of his limitations; or when it treats him according to criteria that are not based on the integral reality of the human person, with the risk of violating his dignity. In this case, it exposes man to the whim of others, depriving him of his autonomy"10.
Any criterion of "better" or "worse" would, at this level, be no more than an arbitrary criterion, dependent on the subjective taste staff of scientists, or of a society. The only criterion goal would be to form morally better generations, but this is precisely what is not achieved either artificially or by biology.
Notes
(1) RODRIGUEZ VILLANUEVA, J. and GARCIA-ARCHE, I. "Aspectos éticos de la ingeniería Genetics". Cuadernos de Realidades Sociales (high school de Sociología Aplicada de Madrid) nº 27/28, January 1986.
(2) JOHN PAUL II. "speech to the General Assembly of the World Medical Association association ". February, 1984.
(3) LEJEUNE, J. "The instincts of love". In "Some questions of sexual ethics". Various authors. BAC Popular, p. 85. Madrid, 1976.
(4) JACOB, F. "Tératocarcinome et differentiation cellulaire". La Recherche, 9, 421, 1978.
(5) INCIARTE, F.: Comunicación oral.
(6) LOPEZ MORATALLA, N. "Significados naturales y knowledge científico". conference proceedings del I congress Internacional de Teología Moral. Rome, 1986.
(7) It could be said to involve the exchange of one person for another person: the first would be properly killed, and the second would be "constituted" from the elements of the first and the other materials introduced. What until a few decades ago was only the subject of fantasies in science fiction novels is now presented as a real possibility. Manipulation Genetics can realise Dr. Frankenstein's experiments in a technically perfect way.
(8) JOHN PAUL II. "speech to the General Assembly of the World Medical Association association ". February, 1984.
(9) LEWONTIN, R. "La diversidad humana". Ed. Labor. Barcelona, 1984.
(10) JOHN PAUL II. "speech to the General Assembly of the World Medical Association association ". February, 1984.