Harvard researchers: embryonic cells can cause cáncer The researchs carried out by the british Sir John B. Gurdon and the japanese Shinya Yamanaka, both awarded with the Nobel Prize in Medicine 2012, gave birth to cellular reprogramming. The conquest achieved, revealed that the efforts put in the investigations with embryonic cells for clinic purposes are useless and completely sterile. But until the nascent induced pluripotent stemm cells (iPS) have clinical use, significant obstacles arises in the use of retroviruses to introduce genetic reprogramming. Currently, according Nature, a way has been found to make the same, without virus. Yamanaka found four genes that provide cells pluripotency, that means the same capacity to generate all the body's specialized cell types, than embryonic stem cells do have. Implanted in differentiated cells, for example of skin, those cells become pluripotent stem cells. The iPS provides plasticity similar to the embryonic stem cells, but do not require to exterminate or clone human embryos, as starting cells can be obtained from the same patient. They have the same privileges as adult stem cells, with the addition of its versatility. The dilemmas raised by the iPS are being resolved by recent studies performed by Keisuke Kaji (University of Edinburgh) and Andreas Nagy (Samuel Lunenfeld Research Institute, Mount Sinai Hospital in Toronto). The iPS obtained retain their pluripotency perennially. It remains to investigate how to control the differentiation of these cells to produce the tissue that is necessary in each case. As Kaji says to the BBC, the investigation has not arrived at the last stage: "'It is a step towards the practical use of reprogrammed cells in medicine, perhaps even eliminating the need for human embryos as a source of stem cells". Clearly the disaster of systematic investigations on embryos, which means their slaughter, and the progress made to research with adult stem cells, has led to the recognition in the scientific world, of the successes achieved with adult stem cells. Faced with the ethical dilemmas posed by embryonic cells, which can cause rejection and even cancer, researchers at Harvard focused their work towards adult cells to transform them into equals to embryonic cells. The Subcommittee for Family and Defense of Life in the Spanish Bishops Conference, says that "Catholics can not support, in any way, practices such as abortion, euthanasia or production, freezing and manipulation of human embryos". Moreover, the UNESCO's Dictionary of Bioethics, asserts that "the use of embryonic stem cells for therapeutic purposes is gravely illicit”. Author and journalist Clemente Ferrer has led a distinguished career in Spain in the fields of advertising and public relations. He is currently President of the European Institute of Marketing. clementeferrer3@gmail.com