Embryonic Stem Cells: Hope Vs. Controversy

Watching actor Michael J. Fox in the throes of Parkinson's Disease reminds us why many people are anxious to find new treatments for a host of incurable illnesses. Embryonic stem cell research holds great promise, but it provokes just as much controversy, CBS News medical correspondent Dr. Jon LaPook reports.

What exactly are embryonic stem cells? And where do they come from?

Embryonic stem cells are collected from embryos created through in-vitro fertilization. One reason these cells are so medically promising is that they have the potential to morph into any cell found in the body, and someday could replace defective cells that cause diseases like Parkinson's, diabetes, and even heart disease.

But opponents of abortion fear that using human embryos for scientific research will encourage their production for profit. They also argue that using human embryos is unethical — that it's tantamount to destroying human life.

"Church teaching is that we value life from conception to natural death. That includes embryos, so we oppose the killing for their parts," says Carole Hogan of the Catholic Conference of Bishops.

Advocates of stem cell research say the embryos produced at in-vitro fertilization clinics are being destroyed anyway.

"All we're saying is that if we are going to do that, let's use that to help people. Let's use that to save lives," Fox said Thursday during an interview with Katie Couric.

Can science find a way out of this ethical dilemma? Adult stem cells from bone marrow, skin and umbilical cords can be used in some cases, but there are limits to what they can do.

For now, all this leaves scientists like Dr. Donald Landry, a devout Catholic, wrestling with a way to square his science and his faith.

"As a Catholic, I appreciate the sanctity of human life," he says. "As a physician, I appreciate the magnitude of human suffering. As a scientist, I appreciate the need for embryonic stem cells for the possibilities they hold."

It's a scientific and ethical debate years in the making, with years yet to run.