Professor Lejeune's testimony to the subcommitee on Constitutional Amendements

National Right to Life News, 1974-06.


Sommaire

Mr. Chairman and Members,

My name is Jérôme Lejeune. i am a doctor of medicine, taking care of disabled children at the Hôpital des Enfants Malades (Sick Children Hospital). I have spent ten years in full-time scientific research, and am now Professor of Fundamental Genetics at theniversity René Descartes in Paris. Having always been a human geneticist, I try to remain human in dealing with genetics.

After working specifically with mongoloid children, I demonstrated that this disease was due to an extra chromosome. For this work, I had the great honor of receiving the Kennedy award from the late President.

Specializing in the study of the human chromosomes, i have frequently visited thenited States, and had the honor in 1970 of receiving the William Allen Memorial Medal in San Francisco from the Maerican Soceity of Human Genetics.

With my colleagues in Paris, we have particularly described many different chromosomal conditions in man, and also compared the chromosomes of man and of primates like the great apes.

We are deeply involved in new techniques of analysis, and have achieved specific recognition of the old and the new chromosomes during celle divisions.

We are also working on the effect of super-numerary chromosomes. in mongoloid children, we have recently demonstrated an excess of a specific enzyme, superoxyde dismutase. the eventual relationship between this trouble and the mental retardation of the affected children is under investigation.

The transmission of life is quite paradoxical. We know with certainty that the link wich relates parents to children is at every moment a material link, for we know it is from the encounter of the female celle (the ovum) and the male cell (the spermatozoa), that a new individual will emerge.

But we know with the same degree of certitude that no molecule, no individual particle of matter enclosed in the fertilized egg has the slightest chance of being transmitted to the next generation. Hence, what is really transmitted is not the matter assuch but a specified conformation of the matter, or more precisly, an "information".

Without receiving the complex machinery of coded molecules like DNA, RNA, proteins, and so on, wich are the vehicle of heredity, we can see that this paradox is common to all the process of reproduction, wheter natural or man-made. For example, a statue must be built out of some material, and could not exist if made of pure void? During the casting process, there exist at every moment a contiguity of molecules between the statue and the cast, and, later, between the cast and the replica. But obviously, no matter is reproduced, for the replica could be plaster, or bronze, or anything else. What is indeed reproduced is not the matter of the statue, but the form imprinted in the matter by the genius of the sculptor.

Indeed, the reproduction of living beings is infinitely more delicate than the reproduction of an inanimate form, but the process follows a very similar path, as we will see by antother familial example. On the magnetic tape of a tape recorder, it is possible to inscribe by minute alterations of local magnetism, a series of signals corresponding, for example, to the execution of a symphony. Such a tape, if introduced in the appropriate machine, will play the symphony, although there are no musicians in the machine and even no notes written on the tape. that's the way existence is played.

But in this analogy, the mangetic tape is incredibly thin, for it is reduced to the size of a DNA molecule, the miniaturization of which is bewildering. To give an idea of this minuteness, we should remember that in this thread every character of each of us is exactly described. Thou sahll have blond hair, hazel eyes ; thou shall be six feet tall, and thou shall live some eighty years, if no road accidents interven ! All these instructions giving a full description of a man are written in a thread one yard long. But the thread is so thin and so carefully packed inside the nucleus of the celle, that it would stay at ease on the point of a needle.

To give another impression, if we were to reassemble on this table all these threads wich will specify each and every quality of the next three thousan million men who will replace us on the surface of this planet, this quantity of matter would fit nicely in an aspirin tablet. The fertilized egg is comparable to a tape recorder loaded. As soon the mechanism is triggered, the human work is lived, in strict conformity to its program.

The very fact that we have to develop ourselves during nine months inside the bodily protection of our mother does not change anything, as you can easily observe by looking at the egg of the hen, from wich the chicken will emerge. It makes no difference wheter he was incubated by the fowl, or by an electric heating device ! The chicken is stilla chicken. If one day a children can be entirely grown in a test tube, the test tube will never believ that the child is its property !

Such a reduction of the human being to its very nature may not be palatable, or intuitively stisfactory, but it accurately reflects the present state of our scientific knowledge. When a new student hears for the first time a symphony, let us say the Little Night Music by Mozart, he must listen to the whole in order to know it. But if he is a music lover, he will recognize Mozart at the first bars, and could tell the title at the second or third bar. It is the same with the human symphony? the specialist can recognize it at its first accents, even if a great number of various movements are required so that its general form becomes evident to everyone.

The infinitesimal threads of the genetic information are carefully coiled in little rods, the chromosomes, easily visible with an ordinary microscope. they are something like the magnetic tape inside the cartridge of a minicassette. Some twenty years ago, nobody could have told the celle of a man from the cell of a chimpanzee. Ten years ago, a simple counting of the chromosomes would have given the answer, 46 if a man, 48 if chimp. Since last year, if a student looking at a divinding fertilized egg or at the divinding celle of a blastocyst, could not telle them apart saying "this one is a chimpanzee being, this one is a human being", he would fail the examination for his license.

But can we say that the early human being is an individual just after fecundation? Does he have the two qualities of an individual : its unity and its uniqueness? Exceptions to unity are known : maybe once in every million births, some subjects carry , side by side, male cells (recognized by their X and Y chromosomes). Thus these subjects are simultaneously provided mith the masculine attributes of Hermes and those feminine of Aphrodite, hence the name hermaphroditism. one would believe that two fertilized egges, one bound to be a boy, and the other bound to be a girl, have united together intimately, and it is quite the case. In the hermaphrodite, the mistake is extremely precocious, and seems to happen at the second division of maturation of the egge. Two reciprocal celles are produced, the ovum and its polar body, which would be here just as voluminous as the ovum. Both of them are simultaneously fertilized, each one by a different spermatozoa. Hence, exceptions to unity can happen very rarely at the time of fecundation.

Exception to uniqueness is more common : the identical twins coming from the same fertilized egg, share exactly the same genetic patrimony, but each of them is obviously an individual by itself. From embryological knowledge, it seems impossible to separate one nature int two (or more) persons after the neural crest, that is, the first appearance of the nervous system, has differentiated. Hence, after the 13ty day, no twins could occur. But, by inference, for the experimentation is not at hand at this time, it seems that the splitting must be extemely precocious, probably at the moment of the division of the first few cells of the embryo, that is, at the first encounter of the paternal and maternal stes of chromosomes.

These remarks on the exceptions of the individual "one and unique" corroborate the notions that every man begins at his very beginning. These theoretical ans experimental notions can sometimes be directly felt by the persons themselves in exceptionnal situations. A very rare accident can occur at the moment the identical twins are formed. From ans XY fertilized egg, bound to be a boy, two celles are produced: one XY will continue its masculine destiny, the other having received only the X chromosome (the Y being lost during the separation process) will develop itself as an imperfect girl. Two X chromosomes are required for a complete and harmonious feminity. Hence, the identical twins will be different : one normal boy and frail and strerile gril.

In the fist case we observed of such a young gril, she was some 18 years old and complained of a strange trouble. She feared to look at herself in a mirror because she pretended she was seeing her brother. Such an impression, far from anomalous, was an extraordinary intuition, very feminine indeed, of a very complex situation entirely undetected at that time. At the exception of the lost Y chromosome, she was effectively a piece of her brother from whom she was issued.

These facts of human genetics can appear a little theoretical, and the question must be asked wheter common sense can recognize as such a tiny human being. if very early, only the scientist aided by refined techniques can tell. If, let us say, at two months everybody knows, and has known for thousands of years.

At two months of age, the human being is less than one thumb's lenght from the head to the rump. He would fit neatly into a nutshell, but everything is there - hands, feet, head, organs, brain - all are in place. If you look very closely, you would see the palm creases, and if you were a fortune teller, you could read the good adventure of that person. looking still closer with a microscope, you could detect the finger prints like Sherlock Holmes - every document is available to give him his national identity card!

The incredible Tom Thumb really does exist. Not the one of the fairy tale, but the one each of us has been. For it is from this true story that fairy tales were invented.

If thom Thumb's adventure have always enchanted the children, if they cans still evoke emotion on grown-ups, it is because all the children of the world, all the grown-ups they have turned into, were one day a Tom Thumb in their mother's womb.

But can we scientists accept these fairy tales? The truth is indedd that Nature itself does. For instance, abortion is a normal process in imperfect mammals called marsupials. They have a special pouch on the abdomen, conveniently accomodated to nurture the little. In the giant kangaroo, the abortion occurs at the same stage as the little Tom Thumb in man, and is roughly the same size. The aborted fetus then climbs into the fur of its mother to reach the pouch. The bewildering fact is that the kangaroo mother will let him do so, although she would not allow any other kind of animal drop in! If the poor brain of a female kangaroo can recognize the tiny creature as a kangaroo being, there is no wonder that geneticists can safely assure you that Tom Thumb is indeed a true human being.

From moleculat genetics to comparative reproduction, nature has taught us that from its very beginning the "thing" we started with is a member of our kind. Being its own, human by its nature, never a tumor, never an amoeba, fish or quadruped, it is the same human being from fecundation to death. he will develop himself if the surrounding world is not too hostile. And the sole roel of medicine is to protect the indivodual from accidents as much as possible during the long and dangerous road of life.