Skip to main content


Subscribe to one of our news e-mail lists.
Enter your address:

CNN Mobile

CNN Websites



CNN International



Number of usable stem cell lines debated

frozen stem cells
Embryonic stem cells, which are extracted from multi-celled human embryos, may be manipulated to create a variety of human blood and tissue cells.  

By Ian Christopher McCaleb, CNN Washington Bureau

WASHINGTON (CNN) -- Congress began asking its own questions about federal funding for human embryonic stem cell research Wednesday, with legislators of both parties taking shots at the Bush administration for issuing a ruling last month they said may have been based on faulty data.

The administration shot back quickly, saying the information provided to President Bush prior to his August 9 decision to allow federal funding for research into a limited number of stem cell "lines" was adequate enough to balance several competing interests, and was accurate.

At a hearing of the Senate Health, Education, Labor and Pensions Committee on Wednesday morning, Health and Human Services Secretary Tommy Thompson sought to deflect bipartisan skepticism of Bush's decision, saying the president made his long-awaited ruling in an "ethical and sound" manner.

"All of us stand today at the precipice of a new era, where science holds the promise of curing the most devastating diseases," Thompson said.

Flash: Embryonic stem cell explainer
Read more about the stem cell research in Proceedings of the National Academy of Sciences
In-Depth: The stem cell debate
Message Board: Human embryo research

"The thoughtful and deliberate decision that our administration made will support policies that preserve and support the sanctity of life, while allowing human embryonic stem cell research to proceed," he continued.

Bush announced last month that he would allow the federal government to fund research into stem cell lines that have already been derived from human embryos. HHS data provided to the White House indicated that there are 64 lines the world over that can be mined for cells that may, in turn, be farmed out to researchers.

Embryonic stem cells, which are extracted from multi-celled human embryos, may be manipulated to create a variety of human blood and tissue cells. The "lines" cited by the administration are cell groups that have already been extracted from embryos, and are capable of reproducing themselves independently.

Scientists are investigating a myriad of therapeutic uses for stem cells, including treatments - and perhaps cures - for diseases such as cancer, diabetes, Alzheimer's and osteoporosis. Researchers also believe stem cells hold the promise to reverse the now permanent effects of spinal cord injuries.

The embryos, however, are destroyed during the extraction process.

Viability of lines questioned

Sen. Arlen Specter argued Wednesday that the lines found by HHS and cited by Bush are in varying stages of development, and questioned whether the few lines of the 64 that are actually "ripe" for research are enough to make the research worthwhile. A probe conducted by his own Senate Appropriations Labor, HHS and Education Subcommittee, Specter said, indicated 200 stem lines would be needed for research purposes.

"A key statement by the president related to 60 stem cell lines, now expanded to 64," Specter said. "But in the intervening several weeks, it has become apparent that many of those are not really viable or robust or usable."

"It is up to the congressional hearings to make a detailed estimation as to the accuracy of representations made by HHS as to robust, viable and diverse lines," Specter continued, before adding his concerns that several stem cell lines had been enhanced with cells from mice, and with "bovine serum."

Thompson acknowledged that Specter was correct about the various stages of some of the stem cell lines, but said it takes time for a line to develop, and estimated that some 24 or 25 lines of cells were now ready for researchers.

"That is adequate" for now, Thompson said.

"The president never spoke about or drew any limits on these lines based on where they were or their development," he said. "Furthermore, we have consistently said that these lines were at various stages of development.

"Unfairly, some are choosing to engage in word games or hear only parts of the story."

Thompson also discounted concerns about the mouse cells - which Rhode Island Democrat James Langevin said could expose humans to "animal viruses."

"The use of mouse feeder lines is not an insurmountable obstacle to clinical trials," he said.

The HHS secretary, in a gesture intended to show that research efforts were moving quickly, told the committee the administration has settled patent questions with the Wisconsin Alumni Research Foundation, which developed the procedure for extracting stem cells in 1998.

The patent agreement will allow a number of research facilities to move forward with their work, Thompson said. But he cautioned that no one should expect any cures anytime soon. And, he sought to frame the government's role as that of facilitator -- enabling the first stages of research to move forward -- before the private sector takes the lead later.

"The cures for these diseases are not just around the corner. I wish they were," he said. "The role of the federal government should be and will be to make sure that basic research takes place."

Panel Chairman Ted Kennedy highlighted complaints from some in the scientific community that Bush's decision to fund only the existing lines would hamper wider efforts.

"Many in the scientific community are concerned that the president's decision will delay development of cures for dread disease for many years, at the cost of countless lives and immeasurable suffering," Kennedy said.

But even Specter, who has aligned himself against the administration's line of reasoning, urged that all proceed slowly.

"It is very important to focus on the need for an independent review on all of these facts," he said. "We should not be precipitous."

• NIH: Stem Cells
• American Society for Cell Biology
• University of Wisconsin Medical School

Note: Pages will open in a new browser window
External sites are not endorsed by CNN Interactive.



Back to the top