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The cloned embryos

News of the cloned embryos immediately inflamed the debate over the ethics of human cloning. Advanced Cell Technology, a privately held company, is trying to patent its cloning technology as part oits for-profit ventures. But critics, particularly the Catholic church and anti-abortion groups, say such a business would immorally destroy thousands of human embryos. In parthenogenesis, an egg cell is treated with chemicals that cause it to start dividing into an embryo without fertilization by sperm. Advanced Cell Technology exposed 22 human eggs to those chemicals.

After five days, six eggs had matured into blastocysts, a spherical structure that is a landmark in the early life of an embryo. Scientists believe embryos created this way could mature long enough to be useful in medical treatment but would be unable to grow to term. Both the cloned and parthenogenetically produced embryos had significant shortcomings. None developed stem cells, which can grow into any type of cell or tissue of the body. Advanced Cell Technology needs stem cells to produce medical treatments for patients.

Copyright, The Times Mirror Company; Los Angeles Times 2001 Allrights reserved) Full Text: A Massachusetts company announced Sunday that it had created cloned human embryos that were able to survive for several days, raising fears that someone could produce a cloned baby and rekindling debate on whether Congress should ban the procedure. Advanced Cell Technology Inc. has no plans to produce cloned children, it said, but instead aims to use cloning to make new cells and tissues for people with diabetes, Parkinson’s disease and other ailments.

The research, however, remains many steps short of what would be needed to create either a cloned baby or human tissue for medical treatment. Still, it marks the first report in a scientific journal of a successful attempt to clone human life. A Korean team claimed in 1998 that it had produced a cloned human embryo, but the research was never published or confirmed. Michael West, chief executive of Advanced Cell Technology, said the work represented “the first halting steps” toward a new era of medicine in which disease would be cured by swapping a person’s faulty cells and tissues for new ones.

It looks like this is going to be possible, but this is obviously only a preliminary report,” West said in an interview. He said his team published early results because it wanted to remain “transparent” about its research amid the sweeping ethical debate over cloning. The research, which required no federal approval, appears in e- biomed: The Journal of Regenerative Medicine, a relatively new online publication. Scientific findings generally do not win credibility until they are published in a journal that subjects the data to review by other researchers.

William Haseltine, editor of the journal and chairman of Human Genome Sciences Inc. , a leading biotechnology company, said the cloning data were scrutinized by independent scientists with the same rigor that is used at traditional journals. News of the cloned embryos immediately inflamed the debate over the ethics of human cloning. Advanced Cell Technology, a privately held company, is trying to patent its cloning technology as part of its for-profit ventures. But critics, particularly the Catholic church and anti-abortion groups, say such a business would immorally destroy thousands of human embryos.

This corporation is creating human embryos for the sole purpose of killing them and harvesting their cells. Unless Congress acts quickly, this corporation and others will be opening human embryo farms,” said Douglas Johnson of the National Right to Life Committee. Some critics say the company is hastening the arrival of cloned children, a prospect that they believe society has not fully considered or regulated. As the company continues to publish its research, these critics say, someone could eventually use it to create a cloned embryo and grow it to term in a surrogate mother.

In a bipartisan vote in July, the House approved broad legislation that would criminalize cloning both as a way to produce children and as a medical tool. If the measure had already been law, West and his colleagues could be subject to jail terms of up to 10 years and $1 million in fines for the work they announced Sunday. The Senate plans to take up the measure in February or March. Cloning critics said lawmakers should move sooner. “This is among the issues pushed to the back burner, or perhaps behind the stove entirely, by the events of Sept. 11,” said Richard Doerflinger, an official with the U.

S. Conference of Catholic Bishops, which opposes human cloning for any purpose. “The Senate has been acting as though this is something way down the road that we can think about when we’re done with terrorism. . . . “But this announcement is a wake-up call that we have to deal with the ethical and social and legal ramifications of cloning right away. ” Prospects for the legislation are unclear in the Senate. Although there is widespread support for barring the cloning of children, some senators seem uncertain whether they want to outlaw a medical technique that might save lives.

Senate Majority Leader Tom Daschle (D-S. D. ) said Sunday that he supported “cloning for research purposes. ” Still, he said the Advanced Cell Technology experiments were “disconcerting. ” “I think it’s going in the wrong direction,” Daschle said on “Fox News Sunday. ” The Senate sponsor of a broad anti-cloning measure, Sen. Sam Brownback (R-Kan. ), called for Congress to swiftly pass a six-month moratorium on all human cloning until the Senate can take up the issue more fully. President Bush has criticized human cloning and praised the House ban.

In its research, the Massachusetts company used two techniques to produce human embryos–cloning and a second process called parthenogenesis. In traditional reproduction, genes carried in the sperm and egg co- mingle to produce an offspring that has a unique mix of its parents’ qualities. Both of the Advanced Cell methods, by contrast, created embryos that were genetic copies of only one parent. The company obtained egg cells from seven female volunteers. It stripped the DNA from 19 egg cells and replaced it with genetic material from another person, also a volunteer solicited by the company.

The new genetic material came from either a skin cell or ovarian material called a cumulus cell. Seven of the eggs began to divide and grow. These early embryos were clones–offspring that carried genes from only one adult, the person who had donated the skin or cumulus cell. Two of them divided into four-celled embryos and one developed six cells before the growth stopped. The growth occurred over a three- day period. West said the embryos were no longer viable and had been disassembled so that their cells could be studied.

In parthenogenesis, an egg cell is treated with chemicals that cause it to start dividing into an embryo without fertilization by sperm. Advanced Cell Technology exposed 22 human eggs to those chemicals. After five days, six eggs had matured into blastocysts, a spherical structure that is a landmark in the early life of an embryo. Scientists believe embryos created this way could mature long enough to be useful in medical treatment but would be unable to grow to term. Both the cloned and parthenogenetically produced embryos had significant shortcomings. None developed stem cells, which can grow into any type of cell or tissue of the body.

Advanced Cell Technology needs stem cells to produce medical treatments for patients. A wide array of researchers is trying to understand how stem cells grow into other cell types, such as insulin-producing cells for diabetics. Researchers may face a significant hurdle even if they can produce tissues from stem cells for human transplant. The patients might reject the new tissue as a foreign substance. Advanced Cell Technology and a small group of other private companies say cloning could produce tissues that match the genetic makeup of individual patients.

This tissue might be more readily accepted by the patient’s body. “Our dream is that someday we could take a patient’s cell, skin cell, and give them back anything that they needed to cure disease,” West said Sunday on NBC’s “Meet the Press. ” Some critics said Advanced Cell Technology’s work, so far, is a failure,not a triumph. “It seems that if you take eggs and don’t develop them beyondthree days, they don’t have success,” said Alexander Capron, a USC professorof law and medicine.

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