Although many religious thinkers cheered the news last month of a breakthrough in stem cell research, the moral controversy may not end anytime soon.
The announcement—made by independent teams of scientists working in Japan and Wisconsin—holds the promise of cures for a host of debilitating and terminal diseases. Scientists have studied embryonic stem cells because of their potential to become any one of more than 200 types of tissues in the human body.
However, research on stem cell development has proven highly controversial because human embryos are destroyed in the process. In addition, some scientists have proposed cloning human embryos from patients with certain diseases. Such cloning would prevent rejection of any new tissues or organs grown from the stem cells and used for those patients. Many religious groups—and many nonreligious bioethicists—find both prospects ethically troubling.