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Senator BayH. Dr. Lejeune, may I ask you to return to the mongoloid situation in which you have significant expertise ?
You say you can predict that trait at about what age ?
Senator Bays. In light of your study, can you predict any possible medical discoveries or genetic discoveries that could result in curing mongoloidism?
Dr. LEJEUNE. Sir; I cannot answer your question because we have not yet found the treatment. If you ask me whether I do believe the treatment is possible, my answer is directly, yes. But we have not yet achieved it. For the moment we must say that there is no treatment available to counteract the mental deficiency of mongoloid children. But to say that it will be impossible in the next few years would be a scientific mistake.
Senator Bays. Could I ask both of you to define for our record just exactly what conception is and when it occurs? When does life begin?
That is, of suppose, the most important question that we are trying to answer.
In technical terms, when does it actually all happen?
Dr. LEJEUNE. For geneticists, the beginning of life occurs at fecundation, that is at the putting together of the two chromosomal patrimony coming from the mother and from the father.
Senator BAYH. Is that the same as fertilization?
Dr. LEJEUNE. That is what you would call fertilization and it happens at one moment, at the mo ent the two cell nuclei will fuse. I would say very simply, sir, that before abortion was discussed, no scientist had any discussion about what was fertilization, at what moment it was taking place. It is taking place at the beginning of life, which is fusion of the first parental cells.
Senator Bayh. You mentioned that the development of twins occurs when two sperms
Dr. LEJEUNE. For the ordinary twins, there are different eggs. They are just brothers and sisters. There are two eggs, two spermatazoa, and two people from the very beginning. For the identical twins, they come from the first egg, which split in two cells, and instead of the two cells continuing to collaborate together to make one individual, each of the cells continues for herself and builds another individual. Senator Bayh. Two separate sperms always? Dr. LEJEUNE. No, no, with one sperm. Senator Bayh. One egg, one sperm? Dr. LEJEUNE. One egg, one sperm, divided into two cells, and each cell gives an individual. But that is an extremely early process.
Senator BAYH. Let me ask either or both of you gentlemen to discuss what legal or moral problem we might have relative to certain types of contraceptive substances or devices that are used by women that, at least according to some testimony we have heard, affect implantation
Dr. LILEY. Well, I would agree entirely with Professor Lejeune, that human life begins at conception, and this has never been seriously disputed, or was not until the abortion controversy, a hot one.
Indeed, we do have several antenatal teach-films which portray this event, or early start out by pointing out this the exact moment in which a new human life begins. Of course this is not an externally verifiable fact until implantation occurs, so that, if I could say my wife has had five children and no miscarriages, strictly I do not know how many children she has conceived that we did not know of because they did not implant. And insofar as I am not sure of the situation in America at all, but in any other country if one is going to sustain the charge of killing, one has got to produce a body. Normally there is an interval between fertilization and implantation, when strictly one does not know when there is anything there or not at that stage.
I would agree in these terms that there is a grey area for the opponent of abortion, one could say that it is morally not the intention to interfere with something if it is there. It is just as bad, if there were something there. But on the other hand, this grey area is limited to the space of perhaps at most 8 or 10 days very early in gestation. It is not nearly as large as the grey area that extends at the other end, when one sees whether abortion is to be prescribed after 12 weeks, 18 weeks, 20 weeks, 24 weeks, 28 weeks and so on. There is a grey area in which one is not sure whether in fact a pregnancy or a conception has occurred, because this is not an externally verifiable fact until implantation and various tests are available.
Dr. LEJEUNE. If I understand your question, Mr. Chairman, it was whether we consider that if the human being begins at fecundation, any prevention of fetus implantation would be killing that human being. Then the answer is yes, it would be killing a very tiny human being.
The other side of the answer would be that we do not know how, for example, intrauterine devices work, and some people say it prevents implantation. It is obvious that in many cases, at least in one experiment done in monkeys, it prevented fertilization. Then, I think that at the actual stage of scientific knowledge, no legal rule could be made just because we do not have the scientific evidence, and you cannot base any legal proposal on a scientific basis if the scientific basis is not there.
Senator Bayh. What has been your experience in those pregnancy studies that you are aware of about the earliest time during the period of gestation that life can survive outside the mother's womb, and how frequent are those instances ?
Dr. LILEY. I would say, Mr. Chairman, that there is a considerable spectrum of stages at which life may be possible for a fetus without its intrauterine life-support system, and part of this, the confusion is made a great deal worse, of course, always by possible uncertainty in maturity of a fetus. And then, for good measure, it is made more uncertain because of the variable rate of maturation in individual babies. In other words, just as we do not expect every girl to have immediately her first period on her 12th birthday, it is spread over quite a spectrum.
And similarly, we do not expect every woman to be menopausal at 45. It is spread over quite a range. Similarly, we do not expect every baby to be bom exactly 283 days from the first day of the last menstrual period. Nor does it follow that every baby is able to live
outside the uterus at 28 weeks. Some do not make a very good job of it at 34, 35 weeks, and some do at 24, 25.
To my knowledge, the earliest reasonably substantiated case of extrauterine survival was in a child just under 23 weeks. But obviously, this in turn is very much predicated by the life-support system available to that baby as soon as it is born.
Dr. LEJEUNE. Mr. Chairman, I am not a specialist on fetus, but I would like to stress a very simply analogy. A fetus inside this ambiotic thing is very comparative to a cosmonaut in a space capsule. Now, you send a cosmonaut to the moon and he has his catheter and he has a whole supply to survive. Now, if you opened this catheter, the cosmonaut on the moon would not live. But nobody would believe that this cosmonaut is not viable. It just means that he can live on the moon if you respect his space suit.
It is exactly the same thing with the human fetus. No matter how big it is, it will survive if you do not break his survival system. That he is viable from the very beginning under the normal conditions.
Senator Bayh. Dr. Liley, you are with the support system.
Do you anticipate perfection in that support system that will move that age down from 34 weeks, where you say it has a pretty good chance, to 32, where there have been examples, on down to an earlier
Dr. LILEY. I would be completely confident, Mr. Chairman. Just because we happen to be at the forefront of medical science in this field, we are certainly not arrogant enough to assume we are at the pinnacle of it.
Senator Bayh. Any question, gentlemen?
Our next panel will be comprised of Dr. Gerald M. Edelman, professor at Rockefeller University in New York; Dr. Norton Zinder, professor of genetics, Rockefeller University in New York; and Dr. John D. Biggers, professor of physiology, laboratory of human reproduction and reproductive biology, Harvard University School of Medicine in Boston.
May I inquire for the record, is it Dr. Biggers, Dr. Zinder, Dr. Edelman?
Gentlemen, I hate to say this, but we have just been alerted that there is a vote going on. Rather than get started and have to interrupt in about 5 minutes, I think it would be better for you and for us if we ask you to forgive us. We will be back as quickly as we can.
TA brief recess was taken.]
Professor Edelman, I understand that you are going to be the leadoff witness.
STATEMENT OF GERALD M. EDELMAN, M.D., PH. D., PROFESSOR,
ROCKEFELLER UNIVERSITY Dr. EDELMAN. Mr. Chairman and members of the subcommittee, I am pleased to have this opportunity to testify in these hearings. Perhaps I should begin by identifying my fields of expertise and by briefly discussing my background. Although I am a professor at the Rockefeller University in New York, I do not represent that institution here.
Rather, I speak as a scientist with some experience in cell biology and in molecular biology, and also as a concerned citizen. My main fields of scientific inquiry are immunology-or how the body distinguishes self from not-self-and various areas of cell biology, particularly cell growth and division, and the analysis of the structure of spermatozoa, including those from human beings.
I was first educated as a physician and after a year of medical training at the Massachusetts General Hospital, spent 2 years in general practice, including obstetrics, as a Captain in the United States Army. Subsequent to that, I obtained a doctoral degree in protein physical chemistry. For the last 14 years, I have spent most of my time doing medical research. In 1972, I was the recipient of the Nobel Prize in Physiology or Medicine for work on the chemical structure of antibodies.
As I understand it, one of the main questions before this committee is whether we can tell when life, particularly human life, begins. I hope to show that, from the scientific point of view, this question is unanswerable, because it is not formulated in terms that can be dealt with operationally. It is important, I believe, to make this remark before getting to any substantive matters, in order to avoid large amounts of useless rhetoric. I should add that it is equally useless to comment on tautologies represented by statements that, for example, “the union of the sperm and the egg represents the first occasion in which the full genetic potential exists for the growth of an animal”, a statement which is undeniable by logic alone.
The detailed comments I shall make about the role of science in such matters may sound negative to this subcommittee, but I believe that there are many questions that cannot be answered by scientific experimentation that are nonetheless important and obviously need to be answered. It seems to me that this in no way restricts the value of expert testimony by scientists. Indeed, one of the tasks before this committee is to determine whether the main question can be answered by scientists. I believe it cannot, but also believe that my obligation is to explain why it cannot. If you know what you cannot do, you are way ahead, even in fields outside of the law.
It may seem to this committee, which has heard the strong statements of previous testimony, that this is a weaker position. But I believe that the statements made in that testimony represent a straw man, consisting of a mixture of scientific fact, philosophic conjecture and personal opinion, all represented as scientific.
In rebuttal to this position, I can only say that I know of no scientific paper in any reputable journal that has proven when life indeed begins. If such a paper exists, I would certainly be glad to know of it and to know whether its claims have been verified.
The great advances in modern biology at the level of both living cells and the molecules of which they are made reveal that there is no scientifically sound way of distinguishing the living from the nonliving. For example, viruses have all the properties of living cells except the capacity for independent existence: they contain genetic information and they evolve, they reproduce themselves and they grow. Yet, they have a completely definable molecular structure and they crystallize just as molecules crystallize and may therefore seem to be dead. At a higher level, it is clear that there is a continuum of properties possessed by cells, tissues, organs and individuals.
If one asserts that a fertilized egg contains a full complement of genes from the father and the mother, and is therefore privileged as "more alive", then counter examples can easily be brought to mind. Biologists have produced complete frogs from eggs alone without sperm and have even produced frogs from the nuclei of skin cells, which contain just as much genetic information as a fertilized egg.
Such complete genetic information is, in fact, in every cell of the body except sperm and eggs, yet no one raises issues about the loss of skin cells or even brain cells for that matter. Losing a sperm, or millions of them, or losing an egg each month would on this basis be a horrendous loss, for they too are "alive", yet it occurs normally to everyone.
Senator Bayh. Excuse me, Dr. Edelman.
Has that type of reproduction that you alluded to, as far as the frog is concerned, ever been done in a human being?
Dr. EDELMAN. No, sir. But a frog, as far as we know, reproduces by the same processes in the fundamental sense as a human being, and that experiment has definitely been carried out. The nucleus of a frog's skin cell has been placed inside the cytoplasm of an egg, and a complete frog has been produced. That is because that skin cell, like every cell in your body, carries' a complete complement of genes from both the mother and the father.
Senator Bayh. When did this experiment take place? Dr. EDELMAN. That experiment was done by Gurdon in Oxford, England in 1971. I am not exactly sure of the earliest paper.
Senator BAYH. Is there something unique about the cell of a frog as distinguished from the cell of a human being that would allow these developments 2 or 3 years ago as far as frogs are concerned, and the same formula not apply to the reproduction of a human?
Dr. EDELMAN. As far as I know, this experiment has not been extensively tried in all of its details, until say 10 years ago, and it is a relatively new technique which is just being explored. The experiment at the level of amphibians is a success, and the information involved in that experiment and the conclusions to be drawn are these : that the genetic information is contained in every cell of the body sufficient to create an individual frog.
Senator Bayh. Excuse me for interrupting.
Dr. EDELMAN. Well, from this point of view, I believe that a zygote needs no more protection from the law than an egg.
If one somehow attempts to glorify a fertilized egg or even an early embryo, one must confront questions that are not capable of scientific answers. At what step of development does a living, individual human being appear? This is essentially a religious and moral question and is therefore open to sectarian interpretations and prejudices.
Science, can assert that people are not cells or just collections of cells. It is the set of capacities of a whole person, for example, the capacity to be conscious, self-aware, develop and absorb culture that defines an individual. Although a fetus may have the potential for these, it has no more than any other collection of cells and certainly has not these capacities.
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