Third Part: New Treatments which Involve the Manipulation of the Embryo or the Human Genetic Patrimony
Knowledge acquired in recent years has opened new perspectives for both regenerative medicine and for the treatment of genetically based diseases. In particular, research on embryonic stem cells and its possible future uses have prompted great interest, even though up to now such research has not produced effective results, as distinct from research on adult stem cells. Because some maintain that the possible medical advances which might result from research on embryonic stem cells could justify various forms of manipulation and destruction of human embryos, a whole range of questions has emerged in the area of gene therapy, from cloning to the use of stem cells, which call for attentive moral discernment.
Gene therapy commonly refers to techniques of genetic engineering applied to human beings for therapeutic purposes, that is to say, with the aim of curing genetically based diseases, although recently gene therapy has been attempted for diseases which are not inherited, for cancer in particular.
In theory, it is possible to use gene therapy on two levels: somatic cell gene therapy and germ line cell therapy. Somatic cell gene therapy seeks to eliminate or reduce genetic defects on the level of somatic cells, that is, cells other than the reproductive cells, but which make up the tissue and organs of the body. It involves procedures aimed at certain individual cells with effects that are limited to a single person. Germ line cell therapy aims instead at correcting genetic defects present in germ line cells with the purpose of transmitting the therapeutic effects to the offspring of the individual. Such methods of gene therapy, whether somatic or germ line cell therapy, can be undertaken on a fetus before his or her birth as gene therapy in the uterus or after birth on a child or adult.
For a moral evaluation the following distinctions need to be kept in mind. Procedures used on somatic cells for strictly therapeutic purposes are in principle morally licit. Such actions seek to restore the normal genetic configuration of the patient or to counter damage caused by genetic anomalies or those related to other pathologies. Given that gene therapy can involve significant risks for the patient, the ethical principle must be observed according to which, in order to proceed to a therapeutic intervention, it is necessary to establish beforehand that the person being treated will not be exposed to risks to his health or physical integrity which are excessive or disproportionate to the gravity of the pathology for which a cure is sought. The informed consent of the patient or his legitimate representative is also required.
The moral evaluation of germ line cell therapy is different. Whatever genetic modifications are effected on the germ cells of a person will be transmitted to any potential offspring. Because the risks connected to any genetic manipulation are considerable and as yet not fully controllable, in the present state of research, it is not morally permissible to act in a way that may cause possible harm to the resulting progeny. In the hypothesis of gene therapy on the embryo, it needs to be added that this only takes place in the context of in vitro fertilization and thus runs up against all the ethical objections to such procedures. For these reasons, therefore, it must be stated that, in its current state, germ line cell therapy in all its forms is morally illicit.
The question of using genetic engineering for purposes other than medical treatment also calls for consideration. Some have imagined the possibility of using techniques of genetic engineering to introduce alterations with the presumed aim of improving and strengthening the gene pool. Some of these proposals exhibit a certain dissatisfaction or even rejection of the value of the human being as a finite creature and person. Apart from technical difficulties and the real and potential risks involved, such manipulation would promote a eugenic mentality and would lead to indirect social stigma with regard to people who lack certain qualities, while privileging qualities that happen to be appreciated by a certain culture or society; such qualities do not constitute what is specifically human. This would be in contrast with the fundamental truth of the equality of all human beings which is expressed in the principle of justice, the violation of which, in the long run, would harm peaceful coexistence among individuals. Furthermore, one wonders who would be able to establish which modifications were to be held as positive and which not, or what limits should be placed on individual requests for improvement since it would be materially impossible to fulfil the wishes of every single person. Any conceivable response to these questions would, however, derive from arbitrary and questionable criteria. All of this leads to the conclusion that the prospect of such an intervention would end sooner or later by harming the common good, by favouring the will of some over the freedom of others. Finally it must also be noted that in the attempt to create a new type of human being one can recognize an ideological element in which man tries to take the place of his Creator.
In stating the ethical negativity of these kinds of interventions which imply an unjust domination of man over man, the Church also recalls the need to return to an attitude of care for people and of education in accepting human life in its concrete historical finite nature.
Human cloning refers to the asexual or agametic reproduction of the entire human organism in order to produce one or more “copies” which, from a genetic perspective, are substantially identical to the single original.
Cloning is proposed for two basic purposes: reproduction, that is, in order to obtain the birth of a baby, and medical therapy or research. In theory, reproductive cloning would be able to satisfy certain specific desires, for example, control over human evolution, selection of human beings with superior qualities, pre-selection of the sex of a child to be born, production of a child who is the “copy” of another, or production of a child for a couple whose infertility cannot be treated in another way. Therapeutic cloning, on the other hand, has been proposed as a way of producing embryonic stem cells with a predetermined genetic patrimony in order to overcome the problem of immune system rejection; this is therefore linked to the issue of the use of stem cells.
Attempts at cloning have given rise to genuine concern throughout the entire world. Various national and international organizations have expressed negative judgments on human cloning and it has been prohibited in the great majority of nations.
Human cloning is intrinsically illicit in that, by taking the ethical negativity of techniques of artificial fertilization to their extreme, it seeks to give rise to a new human being without a connection to the act of reciprocal self-giving between the spouses and, more radically, without any link to sexuality. This leads to manipulation and abuses gravely injurious to human dignity.
If cloning were to be done for reproduction, this would impose on the resulting individual a predetermined genetic identity, subjecting him – as has been stated – to a form of biological slavery, from which it would be difficult to free himself. The fact that someone would arrogate to himself the right to determine arbitrarily the genetic characteristics of another person represents a grave offense to the dignity of that person as well as to the fundamental equality of all people.
The originality of every person is a consequence of the particular relationship that exists between God and a human being from the first moment of his existence and carries with it the obligation to respect the singularity and integrity of each person, even on the biological and genetic levels. In the encounter with another person, we meet a human being who owes his existence and his proper characteristics to the love of God, and only the love of husband and wife constitutes a mediation of that love in conformity with the plan of the Creator and heavenly Father.
From the ethical point of view, so-called therapeutic cloning is even more serious. To create embryos with the intention of destroying them, even with the intention of helping the sick, is completely incompatible with human dignity, because it makes the existence of a human being at the embryonic stage nothing more than a means to be used and destroyed. It is gravely immoral to sacrifice a human life for therapeutic ends.
The ethical objections raised in many quarters to therapeutic cloning and to the use of human embryos formed in vitro have led some researchers to propose new techniques which are presented as capable of producing stem cells of an embryonic type without implying the destruction of true human embryos. These proposals have been met with questions of both a scientific and an ethical nature regarding above all the ontological status of the “product” obtained in this way. Until these doubts have been clarified, the statement of the Encyclical Evangelium vitae needs to be kept in mind: “what is at stake is so important that, from the standpoint of moral obligation, the mere probability that a human person is involved would suffice to justify an absolutely clear prohibition of any intervention aimed at killing a human embryo”.
The therapeutic use of stem cells
Stem cells are undifferentiated cells with two basic characteristics: a) the prolonged capability of multiplying themselves while maintaining the undifferentiated state; b) the capability of producing transitory progenitor cells from which fully differentiated cells descend, for example, nerve cells, muscle cells and blood cells.
Once it was experimentally verified that when stem cells are transplanted into damaged tissue they tend to promote cell growth and the regeneration of the tissue, new prospects opened for regenerative medicine, which have been the subject of great interest among researchers throughout the world.
Among the sources for human stem cells which have been identified thus far are: the embryo in the first stages of its existence, the fetus, blood from the umbilical cord and various tissues from adult humans (bone marrow, umbilical cord, brain, mesenchyme from various organs, etc.) and amniotic fluid. At the outset, studies focused on embryonic stem cells, because it was believed that only these had significant capabilities of multiplication and differentiation. Numerous studies, however, show that adult stem cells also have a certain versatility. Even if these cells do not seem to have the same capacity for renewal or the same plasticity as stem cells taken from embryos, advanced scientific studies and experimentation indicate that these cells give more positive results than embryonic stem cells. Therapeutic protocols in force today provide for the use of adult stem cells and many lines of research have been launched, opening new and promising possibilities.
With regard to the ethical evaluation, it is necessary to consider the methods of obtaining stem cells as well as the risks connected with their clinical and experimental use.
In these methods, the origin of the stem cells must be taken into consideration. Methods which do not cause serious harm to the subject from whom the stem cells are taken are to be considered licit. This is generally the case when tissues are taken from: a) an adult organism; b) the blood of the umbilical cord at the time of birth; c) fetuses who have died of natural causes. The obtaining of stem cells from a living human embryo, on the other hand, invariably causes the death of the embryo and is consequently gravely illicit: “research, in such cases, irrespective of efficacious therapeutic results, is not truly at the service of humanity. In fact, this research advances through the suppression of human lives that are equal in dignity to the lives of other human individuals and to the lives of the researchers themselves. History itself has condemned such a science in the past and will condemn it in the future, not only because it lacks the light of God but also because it lacks humanity”.
The use of embryonic stem cells or differentiated cells derived from them – even when these are provided by other researchers through the destruction of embryos or when such cells are commercially available – presents serious problems from the standpoint of cooperation in evil and scandal.
There are no moral objections to the clinical use of stem cells that have been obtained licitly; however, the common criteria of medical ethics need to be respected. Such use should be characterized by scientific rigor and prudence, by reducing to the bare minimum any risks to the patient and by facilitating the interchange of information among clinicians and full disclosure to the public at large.
Research initiatives involving the use of adult stem cells, since they do not present ethical problems, should be encouraged and supported.
Attempts at hybridization
Recently animal oocytes have been used for reprogramming the nuclei of human somatic cells – this is generally called hybrid cloning – in order to extract embryonic stem cells from the resulting embryos without having to use human oocytes.
From the ethical standpoint, such procedures represent an offense against the dignity of human beings on account of the admixture of human and animal genetic elements capable of disrupting the specific identity of man. The possible use of the stem cells, taken from these embryos, may also involve additional health risks, as yet unknown, due to the presence of animal genetic material in their cytoplasm. To consciously expose a human being to such risks is morally and ethically unacceptable.
The use of human “biological material” of illicit origin
For scientific research and for the production of vaccines or other products, cell lines are at times used which are the result of an illicit intervention against the life or physical integrity of a human being. The connection to the unjust act may be either mediate or immediate, since it is generally a question of cells which reproduce easily and abundantly. This “material” is sometimes made available commercially or distributed freely to research centers by governmental agencies having this function under the law. All of this gives rise to various ethical problems with regard to cooperation in evil and with regard to scandal. It is fitting therefore to formulate general principles on the basis of which people of good conscience can evaluate and resolve situations in which they may possibly be involved on account of their professional activity.
It needs to be remembered above all that the category of abortion “is to be applied also to the recent forms of intervention on human embryos which, although carried out for purposes legitimate in themselves, inevitably involve the killing of those embryos. This is the case with experimentation on embryos, which is becoming increasingly widespread in the field of biomedical research and is legally permitted in some countries… [T]he use of human embryos or fetuses as an object of experimentation constitutes a crime against their dignity as human beings who have a right to the same respect owed to a child once born, just as to every person”. These forms of experimentation always constitute a grave moral disorder.
A different situation is created when researchers use “biological material” of illicit origin which has been produced apart from their research center or which has been obtained commercially. The Instruction Donum vitae formulated the general principle which must be observed in these cases: “The corpses of human embryos and fetuses, whether they have been deliberately aborted or not, must be respected just as the remains of other human beings. In particular, they cannot be subjected to mutilation or to autopsies if their death has not yet been verified and without the consent of the parents or of the mother. Furthermore, the moral requirements must be safeguarded that there be no complicity in deliberate abortion and that the risk of scandal be avoided”.
In this regard, the criterion of independence as it has been formulated by some ethics committees is not sufficient. According to this criterion, the use of “biological material” of illicit origin would be ethically permissible provided there is a clear separation between those who, on the one hand, produce, freeze and cause the death of embryos and, on the other, the researchers involved in scientific experimentation. The criterion of independence is not sufficient to avoid a contradiction in the attitude of the person who says that he does not approve of the injustice perpetrated by others, but at the same time accepts for his own work the “biological material” which the others have obtained by means of that injustice. When the illicit action is endorsed by the laws which regulate healthcare and scientific research, it is necessary to distance oneself from the evil aspects of that system in order not to give the impression of a certain toleration or tacit acceptance of actions which are gravely unjust. Any appearance of acceptance would in fact contribute to the growing indifference to, if not the approval of, such actions in certain medical and political circles.
At times, the objection is raised that the above-mentioned considerations would mean that people of good conscience involved in research would have the duty to oppose actively all the illicit actions that take place in the field of medicine, thus excessively broadening their ethical responsibility. In reality, the duty to avoid cooperation in evil and scandal relates to their ordinary professional activities, which they must pursue in a just manner and by means of which they must give witness to the value of life by their opposition to gravely unjust laws. Therefore, it needs to be stated that there is a duty to refuse to use such “biological material” even when there is no close connection between the researcher and the actions of those who performed the artificial fertilization or the abortion, or when there was no prior agreement with the centers in which the artificial fertilization took place. This duty springs from the necessity to remove oneself, within the area of one’s own research, from a gravely unjust legal situation and to affirm with clarity the value of human life. Therefore, the above-mentioned criterion of independence is necessary, but may be ethically insufficient.
Of course, within this general picture there exist differing degrees of responsibility. Grave reasons may be morally proportionate to justify the use of such “biological material”. Thus, for example, danger to the health of children could permit parents to use a vaccine which was developed using cell lines of illicit origin, while keeping in mind that everyone has the duty to make known their disagreement and to ask that their healthcare system make other types of vaccines available. Moreover, in organizations where cell lines of illicit origin are being utilized, the responsibility of those who make the decision to use them is not the same as that of those who have no voice in such a decision.
In the context of the urgent need to mobilize consciences in favour of life, people in the field of healthcare need to be reminded that “their responsibility today is greatly increased. Its deepest inspiration and strongest support lie in the intrinsic and undeniable ethical dimension of the health-care profession, something already recognized by the ancient and still relevant Hippocratic Oath, which requires every doctor to commit himself to absolute respect for human life and its sacredness”.