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The news from the East

South Koreans extract stem cells from a human embryo and reopen polemic

In the digital age, some scientific publications have the habit of anticipating in their pages on the Internet a part of the content that, in a question of days, will be in its traditional printed edition. They do this when they judge that they have in they hands a pioneering work, potentially bombastic, of immediate interest to their readers, perhaps even to the general public. On February 12, the American scientific magazine Science, one of the most respected amongst academics, resorted to this expedient.  While Brazil was debating the new bill of the Law on Biosafety – which, by regulating the cultivation of genetically modified organisms, advocates the banning  of any form of human cloning, including the kind employed in experiments with stem cells taken out of embryos, a branch of research that is looking for new treatments for a series of diseases -, the periodical’s website supplied an important element for this discussion.

Science published a paper signed by 14 South Korean researchers and one Western one (an Argentinean who has settled in the United States), in which they described the procedures of an unprecedented and successful enterprise: the cloning, for the purposes of research in the therapeutic area, of 30 human embryos, from which a strain of pluripotent stem cells was extracted. What do these stem cells serve for?  A short and simple answer is that they are, theoretically, a “factory of human tissues”.  This is because they are undifferentiated, primordial cells, that can be cultivated for long periods in laboratories, and, by means of the appropriate chemical inducers be transformed, into any kind of cell in the organism (neurons, cardiac tissue, blood, etc.).  This degree of plasticity seems to be exclusive to the stem cells taken from embryos and has not yet been fully documented in stem cells extracted from adults or from other kinds of tissue (umbilical cord).  Hence all the interest of medical research in finding ways of getting stem cells from embryos.

In their experiment, the South Korean scientists used a technique called somatic cell nuclear transfer. First, they removed the cell nucleus – a receptacle of the genetic information – from ovules obtained from 16 volunteers, who took part in the study without any kind of pay. Next, they took the DNA contained in adult cells of these same women and injected it into the ovules from which the genetic material had been extracted. These procedures resulted in the creation of embryos with the same DNA as the adult women, clones of the donors. Finally, the researchers cultivated the cloned embryos and extracted from them a lineage of stem cells. The team from the orient, which guaranteed not having implanted any copy of the embryos in women, was provenly the first to be successful in an experiment of this kind. “Our objective was never to create clones of human babies, but to find the causes of incurable diseases and to offer a new window for cures (if they discover them), said veterinarian Woo Suk Hwang, from Seoul National University, one of the leaders of the South Korean team, who has wide experience in cloning cows and pigs. “We ask all nations to make laws rapidly to prevent human cloning”, stated obstetrician Shin Yong Moon, another key researcher in the South Korean experiment.

The feat reheated the therapeutic cloning versus reproductive cloning debate. In several countries where studies with embryonic stem cells are banned or face serious legal or ethical restrictions, sectors of society in favor of this kind of research, in particular the scientific circles, have stood up for their point of view, pressing their governments to adopt a more liberal legislation on the theme. To offset this, the segments of the population that are against all and every form of cloning also saw in the article in Science a good reason for coming out in public and demand even more restrictive laws. This what happened in Brazil, which was already immersed in this debate because of the draft Law on Biosafety, and also in other countries, like the United States, which, under the presidency of George Bush, has very restrictive legislation on research with embryonic stem cells – a veiled prohibition, actually.

Without public funds
Back in August 2001, Bush had vetoed the use of public money for financing research with new strains of stem cells. There is only money for projects with strains that already existed before this decision was made. As there were few lineages, studies in this field have practically stopped in the USA. The paper in Science, with the news of the successful experiment with therapeutic cloning, may perhaps lead the authorities in Washington to radicalize their position even more.  “The era of the human clone has apparently arrived; today, blastocytes cloned for research, tomorrow, blastocytes cloned to make babies”, said Leon R. Kass, the president of the American government’s Bioethics Council, an advocate of even more severe laws for regulating this question, such as the outright prohibition of every kind of cloning of human embryos.

The embryo begins to produce stem cells when it reaches the blastocyte stage. At this moment, it is no more than a little ball with about 100 cells, and the stem cells needed for medical research can be extracted from it. This procedure is a target of two criticisms against cloning, including the therapeutic kind: the extraction of stem cells causes the death of the embryo, which, in the view of the partisans of this position, is already a human life; the techniques used for therapeutic cloning are basically the same as those employed in reproductive cloning, and they open the way for the creation of genetic copies of human beings becoming a reality in the future.  “Research with stem cells is important, but this kind of tissue should not come from human embryos”, is the opinion of Pope John Paul II.  The defenders of therapeutic cloning also have their arguments (no serious scientist supports reproductive cloning of human beings). They say there is no consensus about the view of the religious that embryos in the blastocyte stage are already a living being, and they claim that it is not unethical to carry on with the researches.

There are those, like British researcher Ian Wilmut, who think, rather, that it is immoral not to go ahead with the studies with embryonic stem cells. This is because these primordial cells can, a few years from now, revolutionize a series of treatments in medicine, such as the transplant of organs, the treatment of chronic illnesses (diabetes, Alzheimer’s disease, Parkinson) and the production of drugs more compatible with the genetic profile of the patients. Wilmut is a researcher with the Roslin Institute, in Scotland, which in 1996 produced the first clone of an animal in the world, Dolly the ewe, which died at the beginning of last year.  The United Kingdom, incidentally, has one of the most liberal laws about therapeutic cloning: by means of licenses issued by the Human Fertilization and Embryology Authority, it allows the use of human embryos discarded by artificial reproduction clinics for experiments with stem cells. The creation of embryos specifically for research purposes is also authorized. Sweden also has legislation similar to the British one. At a continental level, the European Union has also been trying to regulate the question, but has not yet arrived at a consensus, since there are more liberal states and others more conservative about researches with stem cells taken from embryos. As it can be seen, the issue raises controversies everywhere, not just in Brazil, where the Law on Biosafety is being prepared.