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TIME: Almanac 1990
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1990 Time Magazine Compact Almanac, The (1991)(Time).iso
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021389
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1990-09-17
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SCIENCE, Page 64Coming: A Historic ExperimentBiologists get set for gene transplants into humansBy Dick Thompson
For scientists, and possibly for all humanity, a watershed
event is about to take place. Biologists have long been closing in
on a goal that is both alluring and frightening: to alter the
genetic code of a human being. They have transplanted foreign genes
into bacteria, fruit flies, even mice. Now medical researchers at
the National Institutes of Health are ready to take the big step:
within the next two months they will perform the first authorized
gene transplants into humans.
The doctors intend to inject cells containing a gene from the
bacterium E. coli into cancer patients at NIH. The gene itself will
have no therapeutic power, but it will help the researchers monitor
the effectiveness of an antitumor treatment. More important, the
transplantation techniques being developed for the experiment could
someday be used to cure several genetic ills, possibly including
Huntington's disease, sickle-cell anemia and some types of muscular
dystrophy. Says NIH director James Wyngaarden: "We have reached an
important milestone in medical history."
The work combines the efforts of three top NIH scientists:
Steven Rosenberg, an expert in cancer therapy, and W. French
Anderson and R. Michael Blaese, two master gene manipulators. For
several years Rosenberg has been developing a novel cancer
treatment using a type of cancer-fighting cell called TILs
(tumor-infiltrating lymphocytes). He removes TILs from cancer
patients and clones large quantities of the cells in the
laboratory. When this army of cells is reinjected into the
patients, their tumors can shrink significantly. In one experiment
with metastatic melanoma patients, 60% of them benefited from the
therapy. But Rosenberg still needs to know how the TILs move
through the body and why they do not always work.
That is where gene transplants come in. Anderson has developed
a technique using a "marker" that will let Rosenberg follow the
progress of the TILs. The marker is the E. coli gene that makes a
cell resistant to the antibiotic neomycin. Anderson has been able
to tuck that bacterial gene into a virus and then implant the virus
into TILs. Once inside the TILs, the gene becomes fully functional.
In the upcoming experiment, Rosenberg plans to inject ten
terminally ill patients with TILs carrying the marker.
Periodically, he will remove bits of tumor from the subjects and
douse the samples in neomycin. If some cells survive the dosing,
he will know the TILs have reached the tumor.
This limited test is only the beginning. The NIH researchers
and others elsewhere are planning to transplant genes that could
actually help people fight cancer and other diseases. For example,
scientists hope to give patients genes that will enable their
bodies to mass-produce such anticancer agents as interleukin-2 and
tumor necrosis factor. Anderson believes the day is not far off
when it will be possible to transplant a gene containing
instructions for the manufacture of CD4, a substance that combats
the AIDS virus. Ultimately, researchers think they may be able to
conquer some hereditary diseases by replacing defective genes with
normal ones.
As promising as all that sounds, some critics oppose the NIH
experiments on the ground that they set disturbing precedents for
tampering with human genetics. Last week activist Jeremy Rifkin,
a longtime opponent of genetic engineering, filed a federal suit
to block the NIH project, saying such techniques could create
"possibilities for tremendous social abuse." Rifkin fears that
people with genetic abnormalities may be coerced into having
potentially dangerous operations in order to qualify for insurance
or Government benefits.
Evan Kemp Jr., a member of the Equal Employment Opportunity
Commission, who joined the Rifkin protest, fears that industrial
workers might be pressured to undergo gene transplants. Suppose,
he says, that a company is exposing its employees to a toxic
chemical. Instead of getting rid of the poison, the firm might try
to alter the genes of the workers to make them more resistant to
the chemical.
Such a scenario is conceivable, admit the supporters of gene
therapy, but hardly inevitable. Confident that the courts will
reject Rifkin's case, Rosenberg, Anderson and Blaese are going
ahead with preparations for their historic experiment. They
acknowledge that the power to alter genes could be abused. But they
firmly believe that if the technology is used carefully, the
potential benefits to humanity far outweigh the risks.