Big Leap Forward for Stem Cell Research
In the process, cells are taken from a patient. The DNA from those cells is injected into a donated egg whose own DNA has been removed. The egg then grows into an embryo, and its stem cells can be harvested to treat the patient.
The major ethical issue is that the embryo created in this process is viable, and could theoretically be implanted in a uterus to grow into a human baby. In other words, a clone. In addition to the ethical concerns many have about embryonic stem cells, this process opens up the entire issue of cloning.
The research, however, may also provide better ways to study how genetic-based diseases develop. The result could be more effective drugs and alternatives to using genetically modified animals for research -- in itself an ethical issue.