Chimeras are formed by combining genetically-distinct cells, in this case human cells and animal cells. In 2005, the U.S. National Research Council and the Institute of Medicine recommended limits on such research, but 10 years later, they have reopened the debate. Where objections are rightfully raised, language is twisted and manipulated to disguise the truth of what is taking place, making an ethical analysis of a complex situation even more complex. Read

In the unity of life’s development there is no “threshold” after which something that was not yet human becomes human. Science leads us to affirm that if it was not human from the beginning, it would never become so. Therefore, we must cast out any temptation to establish a “before” and “after.” There is no leap, no transformation in essence, by which the zygote, embryo or fetus becomes at some moment of its development something that it wasn’t from its conception. Read

Stem cells have been the object of intense, increasing interest due to their biological properties and the promise they hold for medical advances in the treatment of illnesses that are so far incurable. Unfortunately, this field creates confusion at times, in part because of a lack of understanding about what a stem cell is and in part because of the ambiguity regarding types of stem cells. We hope to clear up some of that confusion. Read