Radishes as big as yams!  Skim milk right from the cow!  Carrots that taste like apples, cucumbers that taste like something, cotton plants that taste like rayon (to boll weevils).  In the early 1970s, when scientists discovered the principles of recombinanat DNA, the only miracle that seemed beyond the reach of genetic engineering was the kosher pig.  At the same time, environmentalists warned that science might accidentally produce a better kudzu instead.  Last week, as the White House announced that regulations would be eased on genetically engineered products in the hopes of spurring their development, it was apparent that both the fears and hopes of the early years had been exaggerated.  As far as is known, none of the plagues that have descended on the head of beleaguered humanity in the last decade was the product of inadvertent (or malicious) genetic tinkering.  And as for revolutionary new vegetables . . . well, at least one variety has gone on sale at some supermarkets.  They are “VegiSnax Sweet Mini-Peppers — the only peppers in the world developed and grown specially for snacking.” One gets the feeling that Crick and Watson were aiming a little higher.

To put things into perspective, genetic engineering is just a more powerful tool to do what Luther Burbank did: alter the genetic makeup of existing species to make them more useful.  No one worried that crossing a tangerine and a grapefruit would unleash a devastating plague of tangelos.  Accordingly the administration has decided that genetically altered organisms should not be regarded as inherently dangerous.  They ill be regulated based on their specific characteristics, like other new products.  Even many environmentalists are willing to concede that point, while cautioning that much depends on how the regulations are drawn and enforced.  “We have a basic optimism about the future of biotechnology,” says Douglas Hopkins of the Environmental Defense Fund.

What makes genetic engineering an improvement on old-fashioned crossbreeding is the promise of being able to manipulate specific genes directly — to break down tangerines and grapefruits into their constituent characteristics and combine them to make an infinitude of tangelos.  So far, the process has worked best in simple organisms, such as bacterias.  By isolating the human genes that make useful proteins and implanting them into bacteria, one can obtain a theoretically limitless supply.  Insulin produced this way went on sale in 1982; human growth hormone followed, and within the last few years have come another dozen or so, such as Epogen, which stimulates the production of red blood cells, and Neupogen, which enhances white-cell production.  “Almost every one is a revolutionary drug, in the sense that there wasn’t anything else that did the same thing before,” says Gordon Binder, CEO of Amgen Inc.  More than a hundred such drugs are in human trials or awaiting FDA approval.  One hot area for research is brain proteins, which may bring new treatments for Alzheimer’s and Parkinson’s diseases.

Genetic manipulation of higher animals, on the other hand, has yet to prove its commercial value.  Research on inducing farm animals to grow bigger and faster “has come to a screeching halt,” according to Robert Wall of the U.S. Department of Agriculture.  Pigs with growth-hormone genes implanted grew 18 percent faster on 15 percent less food, and the meat was much leaner; unfortunately, they also died earlier and failed to reproduce.  Bovine somatotropin (BST), a naturally occurring protein hormone that enhances milk production in cows, can be genetically engineered to raise the output of a herd by 10 to 20 percent.  But some states have opposed its use out of fear of its side effects: by lowering milk prices, it can put some farmers out of business.

Flavr Savr: genetic engineering of plants is moving from the laboratory into field testing, but commercial products are mostly still in the future.  Monsanto has introduced genes into cotton and corn seeds that produce leaves with proteins that caterpillars find toxic.  Further along is the Flavr Savr tomato, developed by a California firm called Calgene, Inc.  The Flavr Savr has a gene that turns off production of an enzyme that causes the vegetable to rot.  The tomato is now being evaluated by the FDA, and the company hopes it will be available next year.  A product already on the market is the “mini-pepper” created by a New Jersey firm, DNA Plant Technologies Corp.  Mini-peppers are the size and shape of jalapenos but with a mild, sweet flavor.  They are not actually genetically engineered.  The company uses a technique called somaclonal variation to speed up the process of breeding a new variety; essentially, hundreds of cells from a specimen with the desired traits are cultured in a petri dish, and of the hundreds of new plants cloned in that way the best ones are selected for the next generation.

The company has also developed a canola oil that doesn’t break down under heat and so can be used for cooking.  And Calgene is actually attempting the seeming miracle of transplanting into the canola plant the gene that makes sperm-whale oil, a useful and precious lubricant.  If biotechnology had existed 150 years ago, the whales might have been left in peace.  No wonder environmentalists see promise in it.