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A Lab Raises a Virus--and Lots of Questions


Scientists have created a living virus from scratch--and opened up a Pandora's box. The feat, reported on July 11 in Science's online edition, means that if the genetic sequence of a virus is known, researchers can probably construct it from basic building blocks in a test tube or even design deadlier versions. "This ability creates a situation of peril for all humanity," warns Paul Root Wolpe, senior fellow at the University of Pennsylvania's Center for Bioethics.

He has a point. Eckard Wimmer, a molecular geneticist at State University of New York at Stony Brook and the leader of the virus-creating team, agrees that there is now a real danger someone could recreate smallpox or cook up Ebola virus. But "there could be enormous practical value to our work," he adds. It could lead to crucial vaccines as well as dramatically deepen scientists' knowledge of how viruses work--and how they can be defended against.

Wimmer's experiment was conceptually simple, if technically difficult. His team began with the known genetic sequence of the polio virus, whose code Wimmer read more than two decades ago. Then, with funding from the Defense Advanced Research Projects Agency (DARPA), the scientists synthesized bits of DNA and strung them together into a chain roughly 7,400 molecules long, making a DNA copy of the polio virus' genes. Next, they used a natural enzyme to copy the DNA into RNA--the genetic material used by the virus nature created. Finally, they stuck the RNA into a special sauce filled with chemicals and bits of cellular machinery, such as protein factories called ribosomes. Almost magically, the RNA copied itself and began to make the proteins and other components of the real virus. The result: complete viruses that are just as infectious as their natural counterparts.

Wimmer downplays the idea that he has created a living thing in his lab. "I do not want to say that we created life in a test tube because we would be in deep trouble," he says. The polio virus, he argues, is merely "a chemical with a life cycle." Ethicist Wolpe agrees that the key issue is not whether life was created but rather the potential for terrorists and others to fashion dangerous pathogens they wouldn't have access to otherwise.

The right response? We need to take this threat seriously, says Wimmer--and develop the necessary vaccines and other countermeasures: "It's very important that there is political fallout from this work." Undoubtedly, there will be. On July 13, an elite group of invited guests is to gather at Albuquerque's airport for the unveiling of a breakthrough in business travel. Eclipse Aviation will display on the tarmac its first Eclipse 500--a twin-jet, six-seat aircraft designed to slash the cost of flying a jet and give execs a way to avoid big-airport hassles. Soon, they'll be able to hail an air taxi that whisks them straight from an airport near home to another close to their final destination.

The Eclipse 500's sticker price is less than $850,000, or a quarter of the popular Cessna Citation's. And projected operating costs are just 56 cents a mile, or about half that of any jet now flying. With those numbers, there is no shortage of buyers, such as Aviace, a Swiss startup that wants 112 planes for a network of air-taxi franchises around Europe.

One key to the Eclipse 500's performance is the latest EJ22 jet engine from Williams International in Walled Lake, Mich. Roughly the size of a bongo drum, the engine made its maiden flight on May 30. The Eclipse 500 is expected to take to the sky in a few weeks. A team of physicians will soon test a new treatment for brain tumors based on a most unusual ingredient: the venom of the giant yellow Israeli scorpion. Developed by TransMolecular Inc. in Birmingham, Ala., the drug contains a synthetic version of a protein in the venom and will be tested in 18 patients suffering from glioma, a type of brain tumor that strikes 17,000 Americans each year.

The venom-derived molecule binds to certain types of living cells. When emitted through the scorpion's stinger, it grabs onto nerve cells, paralyzing the creature's prey. In test tube and animal studies, the synthetic protein binds effectively to glioma cells yet leaves other cells untouched.

Researchers hope that by combining radioactive iodine with this molecule and releasing the mixture in the vicinity of tumor cells, they'll be able to kill the cancer without hurting surrounding tissue. "The venom is the smart bomb, and the radioactive iodine is the payload," says Dr. Adam N. Mamelak, director of neurosurgery at City of Hope National Medical Center in Duarte, Calif., one of two test sites.

Cancer researchers have been developing drugs that can home in on tumor cells for the past two decades. But most targeted therapies are based on antibodies--large molecules that don't travel easily through the brain and can cause adverse side effects. This protein is much smaller, so it travels through the brain more effectively, Mamelak says. If the venom-based drug works in humans, it will be a breakthrough: Current glioma therapies are so ineffective that half of those diagnosed die within a year.


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