The Views of the Holy See on Human Cloning


1. The Holy See's Position
2. The biological background of cloning
3. The possible purposes of human cloning
3.1 Cloning on human embryos as a way of making babies
3.2 Cloning human embryos as a means of producing stem cells
3.3 Cloning human embryos as a tool for studying genetic and epigenetic processes
4. Human cloning-regardless of its objective-is contrary to the dignity and integrity of human beings and their right to life
5. Human cloning done for any purpose contravenes basic precepts of international law
6. Conclusion
1. The Holy See's Position

The Holy See firmly supports a world-wide and comprehensive ban on human cloning, no matter what techniques are used and what aims are pursued. Its position is based on (1) biological analysis of the cloning process and (2) anthropological, social, ethical and legal reflection on the negative implications that human cloning has on the life, the dignity, and the rights of the human being.

Based on the biological and anthropological status of the human embryo and on the fundamental moral and civil rule that it is illicit to kill an innocent even to bring about a good for society, the Holy See regards the conceptual distinction between "reproductive" and "therapeutic" (or "experimental") human cloning as devoid of any ethical and legal ground.

The proposed ban on cloning is not intended to prohibit the use of cloning techniques to obtain a number of biological entities (molecules, cells, and tissues) other than human embryos, to generate plants, or to produce non-human embryos and non-chimaeric (human-animal) embryos.

2. The Biological Background of Cloning

Within conceptual and experimental contexts, the term "cloning" has taken on different meanings that in turn presume different technical procedures as well as different aims. Cloning in itself refers to the production of a biological entity which is genetically identical or very similar to the one from which it originated. The term is used to indicate:
a. The production of a nucleic acid (DNA, RNA), a protein, or a cell line starting from a single or a few copies of each of these entities. As individual life is concerned, there are no peculiar ethical and legal questions on these processes.

b. The generation, in an asexual artificial way, of one or more biological individuals belonging to sexually-reproducing species (plants, animals, and humans). As animals and humans are concerned, this can be done either by disaggregating or subdividing an embryo ("embryo splitting") in its early stages of development or through the transfer of a diploid nucleus of a cell from an embryo, a fetus or an adult individual to a denucleated oocyte. In the latter case, if successful, after activation the reconstructed oocyte will develop into an embryo that is capable of further development to term. Regardless of its destiny, a cloned embryo is a cloned individual of a given species at the beginning of its life.

3. The Possible Purposes of Human Cloning

Human cloning is the scientific technique by which a human being is generated. The early but unavoidable result of both embryo splitting and nuclear transfer cloning is the reproduction of a human being at its embryonic stage of development. Thus, human cloning and human embryo cloning coincide, and they are identical with one another. Currently, there are three purposes for which human cloning can be attempted.

3.1 Cloning human embryos as a way of making babies

When a cloned human embryo is implanted in the uterus of the woman to which the generating egg belongs or of a surrogate mother, the delivery of a newborn baby is expected following pregnancy, as has been demonstrated by mammalian cloning. This use of human cloning has been improperly called "reproductive cloning" since its ultimate goal is to reproduce an adult human being.

3.2 Cloning human embryos as a mean of producing stem cells

A second objective of human cloning is to generate embryonic stem cells for tissue engineering and transplantation or use in cell therapy. Once the human embryo is cloned, its further development is arrested before implantation (usually at the blastocyst stage) thereby destroying the further development of the embryo. The proposed name of this sort of human cloning, i.e. "therapeutic cloning", is misleading in that it confounds the purpose of the action with the very nature of the process at stake. Indeed, to produce embryonic stem cells a living human embryo has been deliberately created and destroyed.

3.3 Cloning human embryos as a tool for studying genetic and epigenetic processes

The transfer of a nucleus from a human tissue cell to an enucleated human oocyte and the study of the embryonic development that follows may be performed with an aim to understand the genetic and epigenetic mechanisms of cell growth, potency, differentiation, regeneration and senescence. This kind of experimental design in cell biology has been called "nucleus reprogramming". Despite the innocent name, it involves cloning a human embryo for the sole purpose of experimentation.

4. Human Cloning — Regardless of Its Objectives — Is Contrary to the Dignity of Human Beings and Their Right to Life.

Even if cloning is pursued with the aim of making a human baby that will mature into adulthood so that there is no destruction of the human embryo, this activity is still an affront to the dignity of the human person. As a form of unnatural asexual reproduction, it represents a radical manipulation of the constitutive relationship and complementarity that are at the origin of human procreation as a biological act and an exercise of human love. Cloning objectifies human sexuality and commodifies the bodies of women. Moreover, women are deprived of their innate dignity by becoming suppliers of eggs and wombs. The dignity of the person cloned is similarly threatened because other persons and technological powers exercise undisputed dominion over the duration of this person´s life or his or her unique identity. Reproductive cloning threatens biological individuality and imposes the genetic makeup of an already-existing person on the cloned person. In turn, the cloned person is commandeered by another´s external and internal profile thereby constituting a violent attack on the clone´s personal integrity.

Cloning accomplished for biomedical research ("nucleus reprogramming") or producing stem cells ("therapeutic cloning") contributes to assaults against the dignity and integrity of the human person just addressed in the context of reproductive cloning. Cloning a human embryo, while intentionally planning its demise, would institutionalize the deliberate, systemic destruction of nascent human life in the name of unknown "good" of potential therapy or scientific discovery. This prospect is repugnant to most people including those who rightly advocate for advancement in science and medicine. Indeed, nucleus transfer cloning is by no means the only or superior way to tissue transplantation and cell therapy. The use of multipotent autologous stem cells of post-natal origin together with transdifferentiation approaches to tissue regeneration is a very promising alternative to prevent immune rejection in patients who have received transplants. In addition, the use of "wild-type" and transgenic animals is another way to disclose cell biology´s genetic and epigenetic mechanisms. Medical experimentation on human subjects, as pointed out below, is a crime under international law. This prospect is morally and ethically repugnant even to those who generally favor scientific research. There currently exist alternative methods of scientific cell research that accomplish the same potential objectives without the need to clone a human embryo that will inevitably be faced with destruction. To create life with the planned intention of destroying it violates the basic norms of moral, ethical, and legal considerations designed to protect the individuality and integrity of each human being.

Since the founding of the United Nations, the centrality of the welfare and protection of all human beings to the work of this organization is beyond question. The safekeeping of present and succeeding generations of human beings and the advancement of fundamental human rights is critical to the work of the UN. The Universal Declaration of Human Rights reiterates the sanctity of all human life and the compelling need to protect it from harm. In this regard, Article 3 of the Declaration asserts that everyone has the right to life. With life comes hope in the future — a hope that the Universal Declaration protects by acknowledging that all human beings are equal in dignity and rights. With the right to life comes liberty and security of the person. To ensure this, the Universal Declaration confirms that each human being is an entity who is guaranteed a future filled with the hope of self-determination. To further this end, conditions that degrade any human being with servile status and deny the fundamental rights to life and self-determination are reprehensible.

To better understand these points, it would be prudent to take stock of our human nature at this stage. Each of us, regardless of nationality, gender, race, ethnicity, or religion, share the same origin and are destined to develop as members of communities beginning with the family, the natural and fundamental unit of society. We strive to further our goals for self, family, and country, but we also, as fellow human beings, are called to further the common good for the present and future generations across the globe. We do this to protect all who share and participate in the human condition. However, if some human beings are destined to serve interests that do not take account of these fundamental principles of human nature that are at the center of the UN´s concern, they are reduced to a servile status that denies them the fundamental claim to life and self-determination guaranteed to all. To clone a human being — regardless of the goal1 — is to deny this person´s basic ontological claim that unites him or her to the rest of the human family. This human being has no hope in a self-determining future because his or her individuality will be destroyed to further some research purpose or to enhance the narcissism of a person who has already existed. In either case, the cloned human being is reduced to enslavement that contravenes the fundamental nature of human existence — to be free and to live as a unique individual capable of contributing to the development of the self and society.

5. Human Cloning Contravenes Basic Precepts of International Law.

Various international instruments acknowledge that the dignity of the human person is at the center of international law. Regardless of the objective for which it was done, human cloning conflicts with the international legal norms that protect human dignity. First of all, international law guarantees the right to life to all, not just some, human beings. Facilitating the formation of human beings who are destined for destruction, the intentional destruction of cloned human beings once the particular research goal is reached, consigning any human being to an existence of either involuntary servitude or slavery, and being submitted to involuntary medical and biological experimentation on human beings are morally wrong and inadmissible. Human cloning also poses great threats to the rule of law by enabling those responsible for cloning to select and propagate certain human characteristics based on gender, race, etc. and eliminate others. This would be akin to the practice of eugenics leading to the institution of a "super race" and the inevitable discrimination against those born through the natural process. Human cloning also denies those subjects who come into being for research purposes international rights to due process and equal protection of the law. In addition, it must be remembered that state practice and the development of regional treaties have acknowledged that human cloning conducted for any end is contrary to the rule of law.

6. Conclusion

Every process involving human cloning is in itself a reproductive process in that it generates a human being at the very beginning of his or her development, i.e., a human embryo. The Holy See regards the distinction between "reproductive" and "therapeutic" (or "experimental") cloning as unacceptable by principle since it is devoid of any ethical and legal ground. This false distinction masks the reality of the creation of a human being for the purpose of destroying him or her to produce embryonic stem cell lines or to conduct other experimentation. Therefore, human cloning should be prohibited in all cases regardless of the aims that are pursued. The Holy See supports research on stem cells of post-natal origin since this approach is a sound, promising, and ethical way to achieve tissue transplantation and cell therapy.

  1. Whilst these objectives have previously been discussed, it is worth reiterating them here. One goal of human cloning focuses on the creation of an embryo that will not be allowed to come to term. It will be used for medical research and other objectives that have been labeled as "therapeutic." Another purpose associated with human cloning is "reproductive," i.e., the creation of a human embryo that will come to term and replicate the person from whom his or her genetic material came.

    [text distributed by Holy See mission]

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