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- SCIENCE, Page 59Gene-Splicing Revolution?A new bioengineering method lets sperm do the work
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- The claim is so dramatic and startling that some biologists,
- perhaps mindful of the recent flap over test-tube atomic fusion,
- have been wary of taking it at face value. But an experiment
- reported by researchers at the University of Rome and at that
- city's Institute of Biomedical Technology may mean that the genetic
- engineering of animals -- grafting characteristics from one
- organism onto another -- has taken a major step forward.
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- Instead of using the conventional technique of painstakingly
- inserting foreign genes into an egg cell with a tiny needle, the
- scientists simply bathed sperm cells in a solution of bacterial
- DNA. The sperm, from mice, incorporated the genes by some still
- unknown process, then went on to fertilize eggs in a test tube. As
- the mice matured, 30% of them produced an enzyme normally made only
- by bacteria -- proof that the bacterial DNA had become part of the
- mice's genetic makeup.
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- The experiment has been called a potential "cornerstone in
- biology." Maybe so, but it will hardly make genetic engineering a
- kitchen-table technology. Advocates of gene transplants have long
- pointed to the potential benefits of altered animals --
- disease-resistant pigs, fast-growing cows and the like. Medical
- researchers are already using engineered mice to study the
- mechanics of cancer and heart disease. But genetic engineering is
- a process that involves many difficult steps, and the new
- breakthrough will at best simplify just one of them.
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- Those limitations should help allay the worst fear of biotech
- watchers: the new technique could be used by unethical researchers
- to manipulate the genetic makeup of humans. "It's amazing if true,
- and would make our work much easier," says Steven Holtzman of
- Embryogen Corp., a biotechnology firm with labs in Princeton, N.J.
- But no one is about to abandon the standard technique until other
- scientists complete tests of the Italians' work -- a process that
- is already well under way.