Originally published in San Francisco Chronicle, September 25, 2000, p. D1. <http://www.sfgate.com/cgi-bin/article.cgi?file=/chronicle/archive/2000/09/25/BU61656.DTL&type=science>
News Stories About Tinkering With DNA Miss the Big Picture
Glowing rabbit shows we're creeping toward redesigning human life
Monday, September 25, 2000
Biotechnology has been erupting onto the news pages lately, but somehow the headlines seem to highlight the trivial while missing the profound ways in which we've taken it upon ourselves to reshape life.
A quick survey of last week's headlines includes:
-- Kraft Foods' recall of taco shells that contain traces of a bioengineered corn. The feed was approved for consumption by cattle, not for humans, and the misdirected corn prompted a public outcry.
-- Then there was the story about the artist who persuaded a French zaboratory to splice fluorescent genes from a jellyfish into a rabbit embryo. The altered embryo was planted in a female rabbit, which gave birth to a bunny that glows in the dark, just like a jellyfish.
-- Finally, there came the advisory report, two years in the making, that urged scientists not to do gene-splicing experiments on human sperm or egg cells. The thrust of the recommendation was to forgo any attempt to ``improve'' human inheritance, at least for now.
The common thread in all three stories is the almost magical fact that DNA is a universal software code. From bacteria to humans, the basic instructions for life are written with the same language.
This fact has become evident in recent years as scientists have unravelled and compared the DNA of various creatures.
Earlier this year, when researchers decoded the DNA of the fruit fly, they noted enormous similarities between fly and human genes. We're even more closely related to the mouse -- scientists think about 90 percent of our genes are similar. It is that extra 10 percent that allows us to keep them in cages.
Even more amazing is the fact that DNA is interchangeable between species. A piece of DNA extracted from a human can be made to perform its function inside a bacterium and vice versa. The DNA record suggests that this interchangeability has been a driving force in evolution. Once DNA has found the code to create blood or brain cells, for instance, all future organisms adapted and embellished on this code rather than having to rewrite it. DNA is
the swiss army knife that's always on the lookout to add a nifty new attachment.
The ability to cut DNA from one organism and splice it into another is the foundation of biotechnology. It is the process that allowed the French scientists to create a glowing bunny. In theory, they could have used the same technique to create a glowing human baby.
The ability to cut and paste DNA between different organisms is called recombinant DNA technology. When Bay Area biologists Herbert Boyer and Stanley Cohen first performed this trick in the early 1970s, scientists were so awed by the power that they declared a moratorium on such experiments until they'd had a chance to think through the ramifications of recombinant DNA techniques.
In time, however, the awe wore off, the moratorium ended and scientists started looking for ways to cut and paste DNA in useful ways.
Diabetics should celebrate the fact that they went ahead. Recombinant DNA techniques made it possible to splice the gene for human insulin into bacteria. When the bacteria grew, they produced human insulin, becoming factories to make a drug safe for human use. Previously, human diabetics had to inject
themselves with insulin derived from the pancreatic tissue of pigs.
Fast forward a couple of decades. Our power to hack into life's software code has advanced dramatically. Today, high schoolers can perform the experiments that earned Boyer and Cohen great fame.
The rapid acceleration in biotech is due in no small part to the fact that we've harnessed bioscience to profits. In the early days of recombinant DNA technology, scientists generally stood at arm's length from industry. Nowadays, we encourage scientists to commercialize their work (see Aug. 21 BioScope).
Right now, the market is the main arbiter for deciding which biotechnologies gain wide use. It should make us uncomfortable to think that our course is being set by the invisible hand.
Fear of profit-driven biotechnology has manifested itself first and foremost in the furor over genetically altered foods. It's one thing to take a bioengineered drug. You know what you're getting and why.
Neither condition is true with the present generation of bioengineered foods. They're not labeled, so a person hasn't got a choice of whether or not to eat them. And for the most part, the current modifications were made to benefit
farmers, not consumers. When biotechnologists spliced in genes for pest
resistance, it may have boosted crop yields but it did nothing for me.
I do find it odd, however, that opposition to biotechnology has fixated almost exclusively on grains when bioscientists make a daily practice of redesigning animals. I'm not just talking about the glowing bunny, a public stunt that at least makes us think.
Rather, every day, in thousands of laboratories, scientists remove genes from experimental mice and rats to see what happens. Or they add genes to these same rodents and observe the results.
Last September, a scientist at Princeton University said he had inserted an extra copy of the gene for a certain brain receptor into a mouse nick-named Doogie. As a result, Doogie seemed to be better at remembering its way through mazes. Articles hailed this as a step toward creating drugs or genetic
alterations to improve memory in humans.
Step by step, we have developed a godlike power to redesign life, without slowing down to attain the godlike wisdom to use it. In the same way that we first orbited the Earth before setting off for the moon, we are building the confidence and boldness to redesign our own software.
No responsible scientist would advocate this today. In fact, a report issued last week by a panel sponsored by the American Association for the Advancement of Science said we should in no way try to affect human inheritance ``without proper oversight and until questions of ethics, efficacy, and safety have been addressed.''
And so we race ahead, almost blind. We have a map of the human genome, but we have no map that tells us where all this knowledge is taking us.
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