Sárospataki Füzetek 14. (2010)
2010 / 1. szám - TANULMÁNYOK - Rusthoven, James J.: Mit jelent embernek lenni a technika korában? Református keresztyén megközelítés.
What it means to be human in our technological age? transplanting cells with repaired genes into a person with a defective gene that causes a particular disease. They might also involve injecting a person with functioning cells that replace cells that died, as in Parkinson’s disease, or that replace cells that stopped producing a life-preserving hormone such as insulin. In 2001, George W. Bush signed a bill in the United States banning federal funding for the creation of new stem cell lines from human embryos. This law forced scientists working in this area to more actively pursue other research directions, including the development of cellular constructs that have characteristics of embryos.5 While this ban has been largely revoked by President Obama, the intervening eight years has seen remarkable new biotechnologies that have altered the ethical landscape of the field of stem cell research. They have changed the options available for developing new treatments using stem cells and have compelled us to ask even more carefully: does moral status differ among human beings at different developmental stages? The first of these new biotechnologies came in the form of a cellular construct developed in animals by a technique known as somatic cell nuclear transfer or SCNT.6 With this technique, the nucleus of a normal somatic cell, such as a normal skin cell, is removed and inserted into an egg cell whose nucleus has been removed. The new type of cell is then stimulated chemically to de-differentiate (i.e., to become less functional and appear more primitive). These cells can divide and take on the appearance and biological characteristics of embryonic stem cells. I call such cellular constructs embryoids because are constructed in the laboratory and assume many characteristics of normal embryonic stem cells are not normally seen in nature. However, theoretically they also have the capability of implanting into a uterus and developing into genetic offspring that are clones of the person who donated its nucleus. Soon, it was shown that such constructs can be produced using human somatic cells and eggs. A related embryoid was soon produced that differed from those produced by SCNT only in the removal or neutralization of a single gene responsible for allowing a cell to implant into a uterus. Produced by a technique called altered SCNT, such an embryoid is considered by some to be ethically more acceptable for research purposes because it cannot implant into a uterus and consequently cannot become a newborn baby. Even some members of the Roman Catholic magisterium became excited that such human embryoids may be more ethically acceptable for research directed toward new medical therapies. Once human cellular constructs were developed, several ethical questions immediately arose from this new biotechnology. Are these truly human embryos or less-than-human entities? How can this technology become available on a large scale if human eggs are required to make them? Is it ethical to pay women to donate their eggs to produce these embryoids for research? 5 These are cells created in laboratory settings that do not occur naturally but are designed to serve a research or therapeutic purpose. 6 Wilmut, I., N. Beaujean, P. A. de Sousa, et al. (2002) “Somatic Cell Nuclear Transfer,” Nature 419: 583-587. SÁROSPATAKI FÜZETEK 57
