Ethics and Genetics

01.07.2004

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Are Human Rights and Human Traditions Threatened by Scientific Progress?
 
 
Prof. Michel Revel
Department of Molecular Genetics, Weizmann Institute of Science, Israel
The human genome project
 
 
 
 
 
 
 

 
 

Introduction

The hereditary properties of living organisms on earth are encoded by the chemical sequences of nucleotides forming their genes. Progresses in molecular genetics have already allowed deciphering the complete DNA nucleotide sequences of several bacterias and yeasts, and the technologies developed are now applied to the much larger genomes of many plants and animals. Since the mid 1980's, an international effort has been initiated to determine the DNA sequences present in the 23 pairs of chromosomes which carry human heredity. Although just over 10% of the human genome is presently known, the completion of this worldwide project sometime during the first decade of the 21st century will revolutionize Medicine and our understanding of human biology. Of the estimated 80,000 genes dispersed along the human DNA molecules, only about 3,000 are known today and these are mainly genes whose alterations cause hereditary genetic diseases. Completion of the human genome project will only be the start of exciting research on the function of each of the genes which direct the development of the human embryo, fashion the body organs and insure the complex neuronal wiring of the brain. Considering the polymorphism of many human genes and intergenic chromosomal segments, it will probably take several decades until we shall each have in our wallet, an electronic card holding the sequence of our own individual DNA. The configuration of the two sets of genes inherited by each of us from our biological father and mother will be known. This may help physicians make more exact diagnoses, but what will this project tell us about humanity?
 
Sequencing of human genomes may at first glance appear as a natural extension of modern genetic technology, but in truth it is a gigantic leap into unknown directions. This is because our concept of what is mankind will be profoundly affected by the choice which has been made, at this point in the history of science, to exploit the primary sequence of the hereditary material as a tool to study man. Philosophers and men of religion have, over the centuries of recorded human history, labored on attempts to define the human with its interfacing intellect, spirit and physical body. Scientific disciplines such as physiology, biochemistry, comparative anatomy, neurosciences have sketched a complex image of biological Homo sapiens, whereas paleohistory, structural analysis of myths and psychoanalysis have sketched a complex image of the human mind and soul. Therefore, it must be made clear that sequencing human DNA is an extreme reductionist approach to the human species, a species characterized by intellectual creativity and interpersonal communication of knowledge and emotions. Examining the chemical structure of human DNA should by no means supersede the other disciplines studying man. The human genome project will reveal the genetic program, through which joined human gametes develop into a human being, but it would be an intellectual disaster to equate Humanity with a DNA sequence.
 
 
 


 

The pitfalls of a DNA dogma

The inherent ethical issue to the whole human genome project is to escape a deterministic categorizing of humans according to their genetic makeup. For Richard C. Lewontin, in The doctrine of DNA , the ideology of biological determinism has been the mainstream commitment of biologists, and its present incarnation is the claim that "when we know the molecule that makes up all our genes, we will know what it is to be human". He reminds us that "development depends not only on the materials that have been inherited from parents (genes, egg chemicals) but also on the particular temperature, humidity, nutrition, smell, sights and sounds (including what we call education) that impinge on the developing organism". There is a "unique interaction between gene (sequences) and environmental sequences" which forms indiviin all their diversity. Environmental conditions can change the genetic abilities, and man creates in large part his private environment: for example, a computer allows handicapped to write. Lewontin warns that the dichotomy of nature and nurture, the Darwinian selection of adapted genes by environment that is nowadays applied to human society by sociobiology, may be fallacies. Humans may differ in their abilities because of innate, genetically inherited differences but these differences are not fixed since changes in environment through education and cultural creativity can deeply modify their impact.

 
Social discrimination could well be the major peril of genetics without ethics. A talmudic text interprets the biblical account that mankind started with a single Adam, as an injunction against discrimination between families, ethnies or races since all humans have a common ancestor; nevertheless man is afflicted by destructive discriminative pulsions. The Human genome diversity subproject led by L. Cavalli-Sforza , confirms the unicity of mankind in its diversity. In fact, about 85% of all identified genetic variations are between any two individuals from the same ethnic group; only 8% are between ethnic groups within a race and 7% are found between major geographical human races. Simply, the Human genome project shows that there are no races separated genetically but, as once said Cavalli-Sforza, the "skin-deep" differences of color irrationally impressed humans into justifying their racial prejudices.
 
There is not one "human genome" since each individual human being has a slightly different genome sequence arrangement, with around 0.2% nucleotide differences. Taking into account that genes occupy only on tenth of the whole DNA, and that not all differences change the protein coded by the gene, one can calculate that about one of every twelve of our maternally and paternally inherited genes differ from those of any random neighbor. Who is then a "normal" human from the genetic viewpoint? The Homo sapiens genome can be easily recognized as distinct from that of other animal or primate species, but there is no "ideal" human genome. Nobody can be qualified as genetically sane or genetically deficient, concluded the Quebec Genethic group . " It is important to conceive man in his complexity and originality, to recognize that all humans carry abnormal recessive genes and susceptibility genes". There could be 5-30 "abnormal" genes in each of us. Such genetic diversity among individuals exist probably in every living species, but mankind is keenly aware of them, very sensitive in detecting the different in the other, and also rightly very sympathetic at the suffering due to pathogenic genetic alterations in a child.
 
The notions of "good and bad", as ascribed to genes, has pervaded into science. Some claim that as Medicine tends to eradicate viruses and other pathogens infecting the human body, it ought to eradicate the "bad" genes. But what is called "bad" genes are in fact alleles retained through selection by some historical environmental conditions, the best example being sickle cell anemia mutations which in Africa protected from Malaria. Often mutations causing diseases have arisen independently at a certain time and in a certain geographical location, indicating a selection process. Who is to know the outcome of their mass eradication by germline gene therapy? Further, how can science, society impose what is normal and what is not. Nazi Germany has shown how short is the road from genetic hygiene, which it evilly adopted from Galton's eugenics, to genocide of "bad" people. The individual has a right to make decisions but these should never be imposed as a society dictate. F.D. Ledley points out "essential distinction between eugenics and genetics in the importance ascribed to individual welfare relative to society". The major advances offered by medical genetics are not eugenic inasmuch that they remain free autonomous medical decisions of individuals to undergo gene screening or gene therapy, or to avoid having offspring with a recognized genetic disease. Human diversity is a fact, and a blessing for mankind. At what point some element of the genetic diversity becomes perceived as an unbearable genetic defect should remain an individual choice for the affected or the fetus-bearing mother.
 
 
 

Bioethics of the Human genome project

These questions of individual diversity and of group norms indeed arrive at the heart of the morality question which Jurgen Habermas describes as being a paradox: "having to resolve at once the double task of preserving inviolability of individuals by equal respect of their dignity, while at the same time protecting the intersubjective mutual recognition by which individuals establish themselves as members of one community. To these two tasks correspond the principles of justice and solidarity".
 
The Human genome and the genome diversity projects will not lead to a rebirth of eugenics and genetic discrimination, if their conduct respects human rights. Toward this objective, the International Bioethics Committee of UNESCO has put forward a "Universal Declaration on the Human genome and Human rights" which has been adopted by the member nations on November 11, 1997. On the Jubilee fiftieth year of the 1948 United Nations Universal Declaration of Human Rights, prompted by the atrocities of World War II, this Bioethics declaration upholds solidarity and justice by proclaiming:
 
Article 1: "The human genome underlies the fundamental unity of all members of the human family, as well as the recognition of their inherent dignity and diversity. In a symbolic sense, it is the heritage of humanity". Article 3: "The human genome, which by its nature evolves, is subject to mutations. It contains potentialities that are expressed differently according to each individual's natural and social environment including the individual's state of health, living conditions, nutrition and education".
 
Like many other national or international bioethics committees, the UNESCO Declaration attempts to set up guidelines to protect freedom, autonomy, privacy and confidentiality toward State, employers, insurance or health companies for all investigations related to one's genome sequence. It also warns researchers about their responsibilities including "caution, intellectual honesty and integrity in carrying out their research" but adds that this applies as well " in the presentation and utilization of their findings" because of the "ethical and social implications" of the Human genome project. Scientist know little about how genes really influence human nature and behavior, and are often misunderstood by the media especially with regards to genes that may contribute some small effect to psychosocial traits, such as aggressivity, intelligence, sexual behavior. Results of the Human genome project do not tell us anything about the essential problem of the unique interactions between genes and environmental sequences1, between genome inheritance and cultural education. The main task of Bioethics is to warn against the ideology of genetic determinism. This task is expressed in the clearest sense by the UNESCO Declaration:
 
Article 2: "a) Everyone has a right to respect for their dignity and for their rights regardless of their genetic characteristics, b) That dignity makes it imperative not to reduce individuals to their genetic characteristics and to respect their uniqueness and diversity".
 
It is beautiful to have such a affirmation of human freedom and dignity in a Declaration dealing with the most colossal genetic program ever undertaken. Curiously, this affirmation is not self-evident because the public perception has been brainwashed into believing that genes determine who we are. This problematic surfaced in accrued furor in the recent debate on reproductive cloning.
 
 
 


 

 

The reproductive cloning debate

Molecular genetics does not only discover genes by cloning DNA but allows to exploit the cloned genes in order to express the proteins that they encode, in particular for the production of proteins with pharmaceutical vasuch as insulin, interferon, growth hormone, blood coagulation factors and so on. Expression of cloned genes entails genetic engineering of bacteria, yeasts or mammalian cells in which the genes of interest are grafted, and regulatory bodies have approved the industrial production of many such recombinant DNA medications. By grafting the genes into whole animals, procedures have been developed which allow producing thousand time larger amounts of given recombinant proteins in the milk of a sheep or a cow. Registration of such procedures by health authorities requires the demonstration of genetic identity between the transgenic sheeps or cows, an identity that can be best insured by cloning the entire animal. The immense progress in IVF has led to the possibility of initiating embryonic development from a mammalian egg (oocyte) from which the resident gametal haploid DNA was removed and replaced by the DNA of a cell from an already existing diploid animal. Since 1987, bovines and ovines have been "cloned" in this way by transfer of very early embryonic cells and in 1997, Dolly the sheep was born from a similar nuclear transfer but this time using the cell from an adult donor sheep . Although this technology is by far not yet established and reproducible, speculations about implications for human reproduction have caused colossal ethical commotion. Without going into the medical potential applications of such a new twist in IVF (treatment of complete sterility or prevention of hereditary disease), or in the scientific hazards and limitations , it is interesting to analyze reactions of bioethics committees to the hypothetical prospects of applying reproductive cloning to man.

 
In January 1998, twenty of the member states of the Council of Europe adopted this statement: "..considering that the instrumentalisation of human beings through deliberate creation of genetically identical human beings is contrary to human dignity and thus constitutes a misuse of biology and medicine.. Article 1: Any intervention seeking to create a human being genetically identical to another human being, whether living or dead, is prohibited." The original text of the UNESCO International Bioethics Committee Declaration was revised by the political inter-governmental committee to include an additional Article 11: "Practices which are contrary to human dignity such as reproductive cloning of human beings, shall not be permitted".
 
If we accept with enthusiasm the anti-deterministic premise that "dignity makes it imperative not to reduce individuals to their genetic characteristics" as in Article 2b of the UNESCO Declaration, how are we to understand that "genetically identical human beings is contrary to human dignity"? A hypothetical child born by an alternate nuclear transfer IVF procedure would be a genetic twin to the donor of the cell used to fertilize the enucleated oocyte. As any other IVF test-tube baby, the cloned child will be born to a mother who carried the implanted embryo through pregnancy and birth. Natural reproduction produces genetic twins once in every 270 pregnancies. One of the major arguments against any ideology of genetic determinism in man, is based on studies of genetic twins who have been raised apart in adoptive families providing different environments. From such research, wrote Thomas J. Bouchard recently , "the results of twin studies refute both biological and environmental determinismthey account for the uniqueness of each of us". Indeed, personality traits of genetic twins correlate only by 50%, compared to fraternal twins 25%, and non-twin siblings 11%. There is genetic influence but by far no identity, in the same way as the environment of a common womb and education conditions do not produce identity. Another study of cognitive abilities in genetic twins raised apart or together and followed throughout life, indicates that genetic factors account for 50% of the correlation, shared environmental factors for 33%, non-shared environment influences 17% , while the error of measurements in such studies is estimated at 10%. From the animal cloning, we know that the genetic program does not determine all the biology, cloned animals have different colored hair spots, the immunological system is not identical and probably so is the brain-wiring since neuronal synapses are largely epigenetic . Maternal mitochondrial DNA, her nutrition and living conditions, the position in the womb, all influence the genetic developmental program. Cloning to make a human replica is an impossible illusion.
 
What is then the meaning of the claim that giving birth to genetically identical human beings, even deliberately, is against human dignity? Do we mean to revive the myth of genetic identity as the old eugenic determinism? Human dignity means education, love, respect of the uniqueness of any person, in short Human Rights. These are not violated by the mere procedure if it is done with respect of the rights of the mother, of the child and of the donor of the genome. The United Nations also recognized the basic human right to benefit from scientific advancement. Upfront banning of a potentially new IVF technology, that could overcome medical problems in procreation, is not a dignified human answer.
 
The Council of Europe statement opposes the deliberate creation of genetically identical human beings as instrumentalisation. This is reminiscent of the opposition to IVF in the early 80's, on the basis that making a human being in a test-tube is undignified. The myriads of children since born by IVF in all its forms, demonstrates the fallacy of such fear: instrumentalized reproduction has not desacralized reproduction but increased the desire and possibilities of unfortunate couples to have their own progeny. IVF is a choice, a difficult one in view of the long treatments needed, but which gives a freedom of choice just as much as adopting a child or remaining childless are valid choices. It could be argued that the ethical issue is in the cloned twin offspring being born much later than the twin father or mother and in another womb. Then IVF embryo freezing and conservation over years should be prohibited; moreover, being born later and from another womb actually decreases yet the risk of exaggerated resemblance between the genome donor and the cloned child.
 
 
 


 

Genetic and other manipulations in the embryo

In the public perception, cloning has been wrongly associated with genetic manipulations to produce humans with certain characteristics. This issue has nothing to do with cloning, which keeps the genome intact, but has to do with the illusion of a human evolution. No less than Stephen W. Hawking has recently made headlines by claiming that if man does not "improve" himself genetically, computers will take over by being more intelligent. But, evolutionists from Charles Darwin to Stephen Gould have recognized that in the last half million years, Homo sapiens sapiens has evolved through a Lamarckian inheritance of acquired culture rather than through natural gene selection. Which genetic changes would be improvements? There is neither an ideal human genome nor an ideal baby. Normality is in the human diversity of "naked capacities for acquiring the ability to do" (L.F. Ward). The dangers of misuse of genetic interventions, for making humans with an increase or decrease in height or other feature (which we would know how to do from animal experiments), or planning illusive changes in IQ when we do not have any evidence that it is genetically fixed, are much more frightening than producing a genetic twin by cloning. Nevertheless, what if the gene change is to fix a hereditary disease? Article 24 of the Universal Declaration states: "The International Bioethics Committee of UNESCO should give advice [..] in particular regarding the identification of practices that could be contrary to human dignity such as germ-line interventions". DNA modifications in the early embryo affect his gametes and future generations. There is danger in tinkering with part of heredity before we know the entire structure and functioning of every bit and piece of human DNA. But if one day we know how to do it, the criterion will be whether investing in genetic changes of man rather than in living conditions and education is not against human dignity. Ethics has the power to avoid sliding on any slippery slope.

 
Embryo splitting, another way for deliberate making of twins, has been realized already in 1993 at George Washington Medical center. The painful and difficult experience of women who undergo IVF could be minimized if done only once in a lifetime, successful embryos being split and some cells being frozen aside to makes them available for a second pregnancy. Splitting 2-4 cell embryos is authorized in many countries for preimplantation diagnosis of genetic disease in IVF embryos from high-risk couples. Another use of early embryonic totipotent cells could be laboratory cultures (without starting a pregnancy) in order to provide pancreatic or liver tissues for transplantation. If done from cloned embryos, the hazards of foreign graft procedures could be avoided. The morality of manipulating embryos depends deeply on culture and religion. Christianity sanctifies life from the moment of fertilization, whereas Judaism and Islam consider the embryo to acquire human nature only after 40 days. The ethical reflection would be wise to respect individual religions and philosophies. As Rene Frydman remarks, the little mass of cells that form the embryo has only meaning within the parental project. Some may view preimplantation selection as more acceptable than therapeutic abortion, but in both it is the capability to assume the charges of parenthood for an embryo with genetic malformation that is the final ethical decision.
 
It is important to know that embryo genetic testing do not increase the overall number of abortions. In fact a Dutch study shows that when no test for a genetic disease was available, 50% of couples at risk did not want to have children, whereas 85%-98% of them decided in favor of procreation once gene testing and counselling for mothers was available. Ethical guidelines consider the mother has final authority on abortion. This is in line with the jewish legal principle that it is the danger that the fetus poses to the mother's life which justifies authorizing abortion. Knowledge of a severe congenital genetic defect may threaten the mother's mental well being enough to accede to her will to terminate pregnancy. The husband or partner agreement is not required, and some view this as a threat to family values. But single parenthood is now recognized socially and legally, and it has not destroyed family values. Treating sterility with anonymous donations of sperm from banks or of oocytes, do not preempt the cultural role of the parents, although they deprive the child of the right of knowing his biological parents and their medical genetic antecedents. This is why some consider fertilization by cloning as an ethical alternative if done only for medical indications. A human child is an end, never a mean, whatever the mean through which he was born.
 
 
 


 

Human biology cannot be separated from culture, tradition and religions

Sex in humans is a cultural activity no less than a biological one. Genetically, the sexual reproduction is cardinal for the maintenance of the healthy diversity of the human species. The mixing of genes, although viewed by some as a genetic game of roulette (J. Fletcher), reduces the chances of recessive genetic diseases and is the substrate on which evolutive selection operates. Insects devised complicated ways to insure gene mixing through sex but humans do not marry only to mix up their genes. Since the early neolithic village, humans have developed rules of kinship and mating in which culture is as much at stake as genetics . Humans practice a measured cultural inbreeding, which may not mix well the genes but preserves cultural inheritance. Indeed, large-scale gene screenings by DNA technology reveal ethnic-specific mutations (e.g. BRCA1 gene) which may be maintained by cultural endogamy . Traditions and religions are cultural factors, which overlay human natural biology.

 
Age-old beliefs imbedded in religious traditions, myths, folklore are important for genetic counselling but often are disregarded by scientists. One of the moral challenges of Bioethics is harmonization between free scientific advances and the multicultural sensibilities which have made mankind. A definition of the Human has to include the age-old values that have been made transparent by the structural analyses of myths , and religious messages must also be investigated to reveal how they mold the structure of our rational mind. Thus, a major contemporary jewish philosopher, Rabbi Joseph B. Soloveichik, reads the first two chapters of Genesis as describing two views of man that are complementary to each other . The description in the first chapter is that of universal man conquering the world, as does the scientist using the rational mind that makes him "at God's image" able to apprehend nature. The second chapter describes community-man with religious feelings and queries, confronted with the Tree of knowledge of good and evil. For Soloveichik, every human has these two sides in his ego and each side has to learn from the other: indeed, the conquering scientific man learns from his alter ego to excel also in the ethical moral sphere. There is no division of tasks between them, but a synthesis and coupling of mutual interactions and exchanges.
 
Within a hegelian dialectic of the Universal realizing itself in the Particular , a universal secular ethics based solely on reason has no reality if it does not understand and accept the lessons of the particular cultural traditions experienced in human philosophies, myths and religions. Only then does ethics go beyond the general utilitarian calculation of costs and benefits, of evolutive adaptation of the species, to care for the old, the physically or socially handicapped or inadapted and recognize each for his particular needs. Religious moral may even threaten universal rational ethics: the more nocive says Nietzsche in his Antichrist , is "the active compassion for all the misfits, the weaks - that christianism". It may be paradoxical that morals as issued from tradition, cultures and religions are not the authoritarian absolute norms feared by modern man, but actually express existential motions, akin to Bergson's "elan vital", that liberate from the egoism of intelligent utilitarian reason . Spinoza, who freed philosophy from dualism of irrational metaphysics, also said: "The Good that anyone who pursues vertue desires for himself, he will similarly desire it for the other humans, and the more so if he acquired a greater knowledge of God" . The monist concept unifying man's nature and moral soul, in line with genetics and neurosciences, needs to be compensated by acknowledging alterity, the existence of others in their endless diversities, which each reflect an Infinite that is the attribute of the Divine. Thus we understand Spinoza: religions, myths, traditions, teach us more than sociobiology or secular humanism alone, about human identity or on how to enhance our desire for goodness.
 
Ethical attitudes to the problems of human genetics are so varied, as illustrated by clashes on selective abortion, cloning or gene improvement, that the best to hope for is an Ethic of Discussion6, in which consensus is not obtained by force, be it force of logical reasoning or of empiric evidence. A fortiori, the religious contributions should not be by force, but by in-depth insights that extract their universal message11. The technology project of the Tower of Babel failed according to the Zohar , because humans having acquired different languages failed to understand each other. Hearing with open heart the voices of plurality, of biologists, physicians, philosophers, religious teachers, lawyers, politicians, will save us from stumbling on the road of scientific progress, over our new freedom of choices

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