1 the Human Embryo Before Implantation Scientific

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1 the Human Embryo Before Implantation Scientific THE HUMAN EMBRYO BEFORE IMPLANTATION SCIENTIFIC ASPECTS AND BIOETHICAL CONSIDERATIONS PROCEEDINGS OF THE TWELFTH ASSEMBLY OF THE PONTIFICAL ACADEMY FOR LIFE Vatican City, 27 February -1 March 2006 Edited by : ELIO SGRECCIA JEAN LAFFITTE LIBRERIA EDITRICE VATICANA 2007 Presentation H.E. Msgr. ELIO SGRECCIA, Msgr. JEAN LAFFITTE Discourse of the Holy Father BENEDETTO XVI Final Comuniqué CONTRIBUTIONS OF THE TASK FORCE - H.E. R. Card. J. LOZANO BARRAGÁN, The culture of death against the culture of life in the teaching of Evangelium Vitae - Prof. M.ZERNICKA-GOETZ, Cells of the early mouse embryo follow biased and yet flexible development - Prof. R. COLOMBO, The process of fertilization and its steges. From parental gametes to a developing one-cell embryo - Prof. G. SICA, The development of pre-implantation embryo - Prof. G. SICA, The embrio-maternal dialogue and preparation for implantation - Prof. C. BELLIENI, Pre-implantation diagnosis, prenatal diagnosis - Prof. K. FITZGERALD, PGD: bio-medical insights and ethical considerations - Prof. M.O. RETHORE', Prenatal and pre-implantation diagnosis from the parents' viewpoint 1 - H.E. Msgr. W.J. EJIK, I The criteria of overall individuality and the bio-anthropological status of the embryo before implantation - Prof. M. PANGALLO, The philosophy of Saint Thomas on the human embryo - Prof. P. IDE, Is the human embryo a person? Status questionis and determination STATEMENTS IN THE ROUND TABLE ""Is the Embryo a Person"" - Prof. A. GIL LOPES, The pre-implantation embryo between biology and philosophy: the individual being - Msgr. I. CARRASCO DE PAULA, The embryo before implantation: between nature and person - Prof. R. SPAEMANN, When does the human being to be a person? - Dr. J.-M. LE MENE', Why is it a duty to protect by law the pre-implantation embryo? - Rev. P. WOJCIECH GIERTYCH, Begotten, not made - Prof. P. SERGEJ FILIMONOV, Si può considerare l'embrione come persona? 2 ELIO SGRECCIA, JEAN LAFFITTE PRESENTATION In successive waves in the world of scientific research, the field ofadvanced medicine and in ethical, political and juridical debate, the identityand the status of the human embryo has been a renewed subject for discussion.In recent times the periods of greatest vivacity in this sense have beenthree in number. The first wave took place in the 1970s, at a time when inEurope the forceful campaigns for the legalization of abortion, campaigns thatwere ideological in character and funded by internationally known pressuregroups, were being developed. These campaigns, underpinned as they wereby the so- called “ sexual revolution ”, secured permissive laws in nearly all ofthe countries of Europe, with the exception of Ireland, Malta and SanMarino. Of those States where abortion was legalized only Poland went backto establishing a prohibition on abortion, and it did this by repealing theabortionist law that had been passed (by the Sentence of the ConstitutionalCourt of 29 May 1997). At that time a copious literature in favour of the legalization of abortioncame into being. First of all an attempt was made to emphasize the principleof the autonomy of the mother (the right to choose, pro- choice). As a result,the full value of the foetus came to be acknowledged beginning with its acceptanceby the mother. This acceptance, therefore, was seen as the real constitutiverelationship of the new human individual. In the view of others, on theother hand, the human value of the embryo was to be recognized only beginningwith the acquisition by the foetus of a figure (a human physiognomy).The ratio philosophica (the autonomy of women) and psychological sensibilitywere associated to deny the full human dignity of the embryo and itsright to life from the onset of fertilization. A second wave took place with the use of artificial fertilization, starting inthe 1980s, and in particular with the publication of the Warnock Report inthe United Kingdom (1984). This was the time of the fifteenth day, thefamous claimed boundary between the so-called pre-embryo and the embryo,which was said to correspond to the pre-implantation period of the developmentof the embryo. Prior to implantation, in fact, the embryo was said“ not yet to exist ” whereas after that time it was said to posses a biologicallywell-defined itinerary. Here various theories were brought into play such asthose on the uncertainty of implantation, on the possibility of twinning(within the first fifteen days of development), and on the necessary presenceof the first elaboration of nervous tissue as an announcement of the possibilityof thinking in a human way. During those years we were often obliged to discuss and rebut the argumentsof the fifteenth day, and the Warnock Report itself confessed that thedevelopment of the embryo, beginning with fertilization, is constant and thatthe date of two weeks of development was a sort of conventional threshold,the outcome of a decision that was needed to end the concerns of thoseengaging in experiments. Recent years have witnessed the “ third wave ”, whose principal axis continuesto revolve around the event of fertilization and the first days of thedevelopment of the embryo within the mother’s body or in a laboratory.First of all, there has been the new fact of the agamic embryo, that is tosay an embryo that is not the outcome of an encounter between two gametesbut which derives from the transfer of the nucleus of a somatic cells into aovule which has had its nucleus removed: in other words, from a procedureof cloning. Is this a real human being? Then there was the discovery of the “ stem cells ” that are present in thehuman organism, a real resource for regenerative medicine, which has openedup a new page in the history of medicine. It was specifically this discoverythat led some advanced researchers to think that the use of stem cells takenfrom embryos could provide “ more effective ” results. Thus was opened upthe front of the fight between some researchers who were the exponentsof the use of somatic stem cells from an adult organism – stem cells whichhad been shown, according to the first promising experiences in this field, tobe able to regenerate tissues in a sick organism – and other researchers whowere the exponents of a 3 hypothetical use of stem cells taken from embryosfertilized in vitro or cloned or frozen. Unfortunately, the extraction of embryocells from the internal cell mass inevitably involves (given present-day technicalpossibilities) the dissection of the embryo (that is to say its elimination) atthe blastocyst stage. In this hypothesis, people came to dream of, and to popularize, a final victoryover grave diseases such as Parkinson’s, Alzheimer’s, diabetes and verymany others for tens of millions of infirm people. This was a flight ofthe imagination that was located on the borders of “ science fiction ”, withoutscientific grounding and even sufficient experimentation on animals. There are those who ask for funds for the first line of research and thosewho seek them for the second; there are those who posit research to produceembryo stem cells without producing an embryo with various genetic contrivancesand there are those who accuse the Church, which constantly refersto the illicit character of eliminating an embryo by invoking its dignity as anindividual human being, of obscurantism and of a sadistic approach to unfortunatesick people who cannot be healed without the elimination (somethingthat is truly sadistic and useless) of embryos that have been cloned or fertilizedin vitro so as to then be broken up and used as a form of miraculousmedicine or panacea. This pseudo-science took on an authentic anti-scientific and very roughmadness and recently it has also been connected with fraud. In order to justify the whole of this rush to the miraculous embryo whichwas to be exploited, cloned, patented and commercialized with internationaljoint ventures, it was necessary to proclaim that the embryo is nothing elsebut a bunch of cells, forsaking calling it a pre-embryo as well. The approachto the beginning of life is thus changed by abandoning the perspective offinalism according to which the beginning should be assessed by taking intoaccount its natural and autonomous outcome, and ends up by judging it solelyon the basis of its present quantity or perhaps on what it can produce to theadvantage of those who exploit it, thereby reducing it to a commodity andending up by eliminating it. Another initiative, that of the day after pill and the even more deadlyRU486, has followed this line: the first is interceptive (it impedes the implantationof a possible embryo in the case of a fertile sexual act); the second, onthe other hand, is able to extirpate the embryo after implantation as well andfor up to more than forty days after fertilization. Those who are in favour of the privatisation of abortion – with consequentsavings for the treasury of a “ socialised ” state which for some time has legalizedsurgical abortion and made it free – have swelled the ranks of those whoaffirm that the embryo is something and not yet someone. Thus, they say, chemicalabortion is not a crime and can be dealt with as a private matter. Lastly, but the story does not finish here, the neologisms ootide and prezygotehave been recently imported from the United States of America todefine (indeed to disqualify) the embryo at the beginning of the process offertilization when the spermatozoon has penetrated the pellucid membranebut has not yet brought about the complete remixing and reordering of itsown genetic material with the
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