ce399 | research archive: (electronic) mind control

UK Licenses Human Embryo Creation (JAMA 7/2003)

Posted in Uncategorized by ce399 on 14/06/2012
Medical News and Perspectives | July 23/30, 2003
JAMA. 2003;290(4):449-450. doi:10.1001/jama.290.4.449

The United Kingdom (UK) has granted a license to Roslin Institute, Edinburgh, Scotland, to create human embryos for stem cell research via parthenogenesis, a “virgin birth” technique that jolts oocytes into a fertilized state without sperm. The license also allows the institute—former home of Dolly the sheep, which died in February—and its lead cloning researcher, Ian Wilmut, PhD, to derive stem cells from embryos created for in vitro fertilization (IVF) .

These nonhuman primate eggs have developed into 8-day-old embryos via a process called parthenogenesis (Science . 2002;295:819) (Photo credit: AAAS)

It is the fourth license for embryonic stem cell research handed out by the government of the United Kingdom, but the first license allowing the creation of human embryos by any means.

Speaking at the National Institutes of Health, Bethesda, Md, Wilmut said that he supports research on all types of stem cells, whether from embryos or adult tissues.

But he added that cloned embryos offer the most promising means for identifying the origins of and treatments for genetic conditions such as amyotrophic lateral sclerosis, or Lou Gehrig disease (JAMA. 2001;285:1691-1693). Embryos created using DNA from individuals with such diseases could provide researchers with an almost unlimited supply of stem cells, each carrying the key genetic defect. Such a pool would allow scientists to undertake more, and more sophisticated, experiments than any other available technology, said Wilmut, who spoke at a conference sponsored by the General Motors Cancer Research Foundation.

INCREASING THE EGG SUPPLY
INCREASING THE EGG SUPPLY

In an interview following his talk, Wilmut said that the aims of the newly licensed research are two-fold: to improve basic stem cell culturing technologies and to increase the supply of human eggs available for research.

INCREASING THE EGG SUPPLY

Roslin will immediately begin collecting embryos donated by patients from IVF clinics, which typically create several excess embryos per pregnancy attempt. The second route to boosting the egg supply, parthenogenesis, is much more technically challenging, said Harry Griffin, PhD, acting director at Roslin.

INCREASING THE EGG SUPPLY

The process involves gathering immature eggs from donors undergoing surgery for nonfertility-related reasons and then coaxing them to maturity in the laboratory. If successful, Roslin scientists will try to glean stem cells from the parthenotes (embryos grown from unfertilized eggs).

INCREASING THE EGG SUPPLY

Roslin’s agenda is the latest in a long line of advances involving parthenogenesis. Decades ago, scientists discovered that some plants and lower animals, including insects and corals, reproduce via the technique. Because the oocytes do not complete meiosis, they contain a full complement of the parent’s chromosomes—a clone.

INCREASING THE EGG SUPPLY
SUCCESS IN PRIMATES

Then in 1936, Gregory Pincus, MD, one of the scientists involved in developing the first birth control pill, induced parthenogenesis in rabbit eggs via temperature change and chemical agents. In 2001, Michael West, PhD, and colleagues at Advanced Cell Technology (ACT), Worcester, Mass, announced the creation of human parthenotes, although many scientists expressed skepticism about the embryos’ usefulness, as they died shortly after creation. A year later, though, a team led by ACT scientists and Kent Vrana, PhD, professor of physiology at Wake Forest University School of Medicine, obtained embryonic stem cells from monkey parthenotes, an advance that sparked a wave of enthusiasm (Science. 2002;295:819).

SUCCESS IN PRIMATES

Roslin is the latest institute to ride that wave, and Wilmut expressed confidence that parthenogenic human embryos will eventually provide a rich source of stem cells for research. But constructing a steady supply of stem cells is just the first step in the research pipeline. Once collected, the cells need to be fed and kept stable.

SUCCESS IN PRIMATES

Because current stem cell lines rely on mouse “feeder” cells, in theory, Wilmut said, unknown viruses in animal feeder cells could find their way into the human cells, a concern that the US Food and Drug Administration has also raised. To avoid that possibility, scientists at Roslin are developing techniques that would rely instead on human feeder cells or, even more ambitiously, on completely cell-free media. That is, the embryonic stem cells would grow in a rich soup of organic compounds.

SUCCESS IN PRIMATES

According to an abstract posted on the Web site of the UK’s Human Fertilization and Embryology Authority (HFEA), the agency that grants stem cell research licenses, Roslin now has permission to pursue this goal, too (http://www.hfea.gov.uk/aboutHFEA/researchLicenses.htm).

TO CLONE, OR NOT TO CLONE
TO CLONE, OR NOT TO CLONE

Like Roslin, the other three UK licensees—Guy’s Hospital, London; the Institute of Stem Cell Research at the University of Edinburgh; and the London Fertility Centre—are culturing stem cells from donated IVF embryos.

TO CLONE, OR NOT TO CLONE

Under a sweeping 1990 law, the HFEA regulates all IVF and human embryo research in the United Kingdom; a 2001 update to the HFEA banned all reproductive cloning and mandated that any artificially created human embryos must be destroyed within 14 days. In March, the House of Lords ruled that despite challenges from antiabortion groups, the HFEA holds the authority to license research involving embryo creation via parthenogenesis and cell nuclear replacement, although cloning for reproductive purposes remains off limits.

TO CLONE, OR NOT TO CLONE

Wilmut did not say if Roslin would pursue a license to attempt the more controversial nuclear replacement technique, the method used to create Dolly. In nuclear replacement, genetic material from an adult cell is transplanted into an oocyte, which is stimulated and begins embryonic development—a procedure that succeeds only rarely. While parthenogenesis allows cloning of reproductive-aged females, nuclear replacement could, hypothetically, clone any person, alive or dead (if viable DNA can be recovered).

TO CLONE, OR NOT TO CLONE

While tightly controlled in the United Kingdom, cloning research in the United States is largely unregulated. Bills outlawing the creation of cloned embryos for reproduction—and also for research, depending on the bill—have stalled in the US Congress, leaving the cloning landscape wide open for private companies. However, restrictions apply to researchers receiving federal funds, who may work with a handful of approved but largely uncharacterized embryonic stem cell lines and are not allowed to create cloned human embryos (JAMA. 2003; 289:1092).

New Stem Cell Center
New Stem Cell Center

As parthenotes and embryos evolve as a source of embryonic stem cells, other researchers are concentrating on adult cells with transformative potential.

New Stem Cell Center

One type, marrow stromal cells, have taken center stage with a 5-year, $4.3 million grant from the National Institutes of Health (NIH) to Tulane University in New Orleans. The funds will support a new center to prepare and distribute standardized, high-quality marrow stromal cells.

New Stem Cell Center

Because producing the cells is technically challenging, the Tulane center will speed basic and, eventually, clinical research, said Judith Vaitukaitis, MD, director of the National Center for Research Resources at NIH.

New Stem Cell Center

Recent research has shown that, when injected into animals, marrow stromal cells populate bone, cartilage, lung, skin, liver, and brain tissue.—B.V.

http://jama.jamanetwork.com/article.aspx?articleid=196988

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