The microscopic cells capable of transforming into brain, heart muscle and other cell types have sparked a huge debate. At issue is whether the federal government should fund research on new lines of stem cells taken from human embryos. Stem cell research is believed to offer hope for problems ranging from cardiovascular disease to cancer to diabetes.

Known as embryonic stem cells, the material is often harvested from leftover embryos created at in-vitro fertilization clinics. A major question swirling around these embryos is whether they should be considered living humans or simply a group of cells.

Hatch, who spoke Friday at the University of Utah, maintains that embryos created in a petri dish are not people.

"I believe that life begins in a mother's womb, not in a science lab," Hatch said.

Some congressional colleagues oppose funding research on new stem cell lines, citing differing views on when life begins.

"A strong majority of the country believes life begins at conception," said Sen. Sam Brownback, R-Kan., in a 2004 story in the Washington Times.

Sen. Hatch reached his position after consulting with scientists, doctors, ethicists and others. He also prayed on the matter and searched the scriptures for guidance.

David Magnus, director of the Stanford Center for Bioethics, said the debate is more complicated than it seems. Some advocates of abortion rights oppose the use of embryos specifically created to obtain stem cells, preferring to only use extra eggs from in-vitro fertilization.

"What's in the dish?" asked Magnus. "What is the moral status of the [out-of-the-womb] embryos?"

Magnus said some anti-abortion advocates can support taking stem cells from leftover in-vitro fertilization embryos because those cells will never grow into living humans.

But many opponents to new embryonic stem cell research argue that life begins at conception - whether it's in a lab or in the womb.

Hatch applauded the Bush administration's willingness to fund certain embryonic stem cell lines, namely those created before Aug. 9, 2001. Any lines created after that date were ineligible for federal funding.

That leaves about 20 available stem cell lines, all of which appear to have been contaminated by mouse material, Magnus said. The mouse contamination, which comes from the material used to coax the embryos into growing, prevents them from ever being used to treat humans.

"They aren't even very useful for bench-side research," he said.

Ray Gesteland, vice president of research at the U., added that some of the funded stem cell lines are not growing well.

"It's certainly not going to be adequate for the future," Gesteland said.

For these and other reasons, Hatch is pushing for passage of two different bills, including the Stem Cell Research Enhancement Act. This bill would lift some of the Bush administration's restrictions on funding stem cells.

The other bill, the Human Cloning Ban and Stem Cell Research Protection Act, would make it a felony to clone a human in the United States. Some provisions of the law would allow researchers to create embryos for the purpose of collecting stem cells.

A problem with the current practice of only using leftover in-vitro fertilization eggs is that they are largely taken from Caucasians. Many in the medical community would prefer to have stem cells from a range of races, Hatch said.

Several states, including California, are working around the Bush administration's funding restrictions by providing state money for research based on new stem cell lines.

Hatch said he hopes the U.S. government acts soon to fund new stem cells lines, or else the nation risks falling behind countries such as the United Kingdom and Australia that are already moving in that direction.