Terminator Technology

My greatest satisfaction is not in having power over people, but in having power over nature. There was a wonderful pleasure in understanding the rules of nature and, having understood them, making those rules work for me. Howard Schneiderman, former leading scientist at Monsanto In the early years of plant biotechnology, and continuing today, major genetic engineering companies such as Monsanto had difficulty, to say the least, in convincing potential customers about the benefits of GM crops....

Bioremediating Bacteria

Even more so than plants, many bacterial species are well suited for bio-remediation efforts. First, they display a variety of genes and metabolic pathways enabling them to utilize a wide spectrum of natural inorganic and organic compounds, many of which are structurally related to man-made chemicals. Second, they can divide and multiply rapidly, thus offering a large biomass for detoxifying environmental pollutants. Third, these microbes reside in abundance in nearly every kind of habitat,...

Barnyard Bioreactors

One year after lamb Dolly's birth, along came lamb Polly, in some ways an even more significant genetic engineering feat. Polly was not only a cloned farm animal, but also a transgenic one The DNA from the fetal cell used to clone Polly first had been equipped with a human gene. Indeed, the cloning was merely a secondary exercise, meant to perpetuate a new biological home for the transgene that was of primary interest. The transgene coded for factor IX, a blood-clotting protein useful in the...

Preface

A scientific revolution is in progress that promises to alter all prior rules on how humankind interacts with the biotic world. Through the laboratory wizardry of genetic engineering, researchers have gained the ability to identify and characterize genes for nearly any biological function, modify these genes and insert them into living cells, swap genetic material freely among species, and even generate perfect genetic copies (clones) of whole plants and animals. By routinely engineering the...

Low Phosphorus Enviropigs

Hog ranches have gone industrial in most of the developed countries of the world and no longer bear much resemblance to storybook images of Old-MacDonald-style family farms. In a modern swine factory, huge rectangular barns house hundreds or thousands of pigs who seldom see the light of day. The animals are fed and bred indoors, and their urine and feces are washed through floor slats to be piped into waste lagoons. As these impoundments fill, surplus offal is sprayed on surrounding fields to...

Accelerated Directed Evolution

Despite all the fancy gadgetry for manipulating DNA in biotechnology laboratories, with few possible exceptions (e.g., see discussion of poliovirus in chapter 2) genetic engineers have yet to create, from scratch, anything so complex as a living entity or organism. How then has nature filled the planet with such inventions It has done so through endless genetic tinkering and relentless selective filtering across billions of years of evolution. The fodder for evolution is vast genetic variety...

Gene Therapies on SCIDs

On the morning of September 4, 1990, near a National Institutes of Health Medical Facility in Bethesda, Maryland, two of the most famous figures in the history of human gene therapy met for the first time. French Anderson, a forceful pioneer of human genetic engineering, was introduced to his newest patient, Ashanthi DeSilva, a cherubic four-year-old girl with a grave illness. Ashanthi had been born with SCID (severe combined immunodeficiency) syndrome, a normally fatal genetic disorder that...

Insulin Factories

Insulin, the diabetes-treating hormone, is now mass-manufactured from transgenic bacteria that have been engineered to carry and express the human insulin gene. The human insulin saga is of historical interest because it provides one of the first success stories in genetic engineering and also illustrates the broader trials and tribulations of the neophyte GM enterprise. In the spring of 1976, in Indianapolis, the pharmaceutical giant Eli Lilly convened a national scientific symposium about...

Antimalarial Mosquitoes

Mosquitoes are not just irritating to humans and other animals, they are also among nature's most dangerous vectors of disease. When mosquitoes suck their blood meals, they sometimes pick up and transmit microbes that are the causal agents of a wide variety of serious illnesses. A classic example is human malaria, which sickens 200 300 million people and causes about 2 million deaths annually, mostly among small children in Africa. The microbial agents of malaria are unicellular protozoans from...

Epilogue

Genetic engineering can be a misleading term if taken to imply undue analogies to physical engineering. When geneticists tinker with the genetic makeup of plants, animals, or microbes, the outcomes can be far less predictable than when a mechanical engineer builds a house, a bridge, or a dam. Each individual organism changes continually during its development, thus posing an ever-shifting physiological milieu for genetic manipulation. At the population level also, nothing remains static, but...

Getting Creative with Crops

About 10,000 years ago, our forebears invented agriculture and its sister enterprise, selective breeding. By purposefully sowing the seeds of desirable wild plants, harvesting the resulting foods or fibers, and retaining seeds from favored specimens for subsequent planting, our ancestors gradually transformed native plant varieties into the bountiful corns, rices, cottons, tomatoes, and other productive domestic crops that we enjoy today. Such artificial selection over the eons required no...

Phytoremediation of Mercury Poisons

Biotechnologists are keen to do more than biomonitor for pollutants they also want to clean up the environment. There is plenty to be done. The Environmental Protection Agency estimates that at least 30,000 polluted sites in the United States are in need of remediation from toxic wastes. In the United Kingdom, 100,000 contaminated sites are known or suspected, affecting about 1 of its total land area. These and untold numbers of other sites around the world are polluted with witches' brews of...

Engineering the Germline

All 100 trillion cells in each adult human trace back to a single diploid cell, the fertilized egg. Nearly all of the cell divisions are mitotic, faithfully repli cating the zygotic genome into armies of derivative cells. Most of these are somatic cells that constitute heart, skin, nerves, liver, muscle, blood, and the body's many other parts. However, a significant event occurs early in embryogenesis when a few thousand amoebalike cells begin to form the primordial gonadal tissues of the...

Going Bananas with Vaccines

In the late 1700s, an English physician, Edward Jenner, administered the world's first medical vaccine. Using a needle soaked in fluid from the open sore of a milkmaid with cowpox (a bovine version of smallpox that produces only mild symptoms in humans), he scratched a farmboy's arm. Upon later exposure to smallpox virus, the boy successfully resisted this otherwise deadly disease. From Jenner's experiment came not only the vaccine concept, but also the word itself, which derives from the Latin...

Engineering Foods for Animals

Another route to better animal health is through improved feed and nutrition. Much of traditional agriculture is devoted to delivering suitable corn, hay, and other fodder to barnyard animals, but high-tech industries have come to the table in recent years to improve the plant-food products or to add dietary supplements to animal feed. Such efforts are laudatory in principle, but they can sometimes backfire with dire consequences, as evidenced by an ongoing debacle in antibiotic use. Livestock...

Herbicide Tolerant Soybeans

In traditional agriculture, weed control was accomplished mechanically, by cultivation or hoeing, or culturally by crop rotation. Then, in the 1940s, chemical herbicides were introduced and weed science became an organized and lucrative enterprise. Synthetic herbicides are of two broad types selective chemicals that affect only certain species or taxonomic families of plants and nonselective chemicals that kill almost every kind of plant. Herbicides were soon incorporated into standard...

Spiders Silk from Goats Milk

What natural substance is stronger than iron, more elastic than a bungee cord, and able to stop speeding bullets If biotechnologists at the Nexia Corporation of Quebec have their way, it will be a transgenic biological fiber (BioSteel) engineered from the silk genes of a spider. With a tensile strength greater than steel, yet a lightness exceeding most synthetic fibers, ounce per ounce spider silk is among the toughest, yet pliant substances known. This amazing combination of strength and...

Transgenic Environmental Biosensors

If transgenic fish can be engineered to serve as living sentries for aquatic mutagens and other pollutants, it should come as no surprise that genetic engineers plan to create and deploy terrestrial creatures in similar fashion. In the last century, miners often placed caged canaries in working tunnels to serve as early-warning alarms to impure air. Likewise, today's biotechnologists hope to deploy a wide variety of transgenic plants, animals, and microbes as sensitive biodetectors of cryptic...

Copy Cats

You might suppose that breaking the technological cloning barrier for sheep or cows would quickly have opened similar capabilities for all mammals. But this has not always been the case in practice some species have proved much easier to clone than others. Sometimes, poor knowledge concerning the basic reproductive anatomy or physiology of a species has been the hindrance. Other times, the reproductive biology is understood reasonably well, yet it remains refractory to successful cloning...

Growth Industry

Insulin was the first human hormone to be produced in commercial quantities by transgenic microbes. The second, following close on its heels, was human growth hormone (hGH), also known as somatotropin, derived from Greek words for body and nourishment. Like insulin, therapeutic hGH has a fascinating and somewhat troubled history. In the human body, hGH normally is produced by the pituitary gland (a small cherry-shaped body attached by a stalk to the base of the brain), and then passed into the...

Possibilities with Poultry

Mammals are not the only farm animals being tinkered with genetically. Chickens are likewise the experimental subjects of genetic manipulation for trait improvement, better breed performance, or as living bioreactors for pharmaceutical proteins. Growing numbers of companies (including Origen Therapeutics of Burlingame, California, Viragen of Plantation, Florida, AviGenics of Athens, Georgia, TransXenoGen of Shrewsbury, Massachusetts, GeneWorks of Ann Arbor, Michigan, Vivalis in France, and...

Rabbit Contraception

In the mid-1800s, English rabbits, Oryctolagus caniculus, were imported to Australia as a convenient source of meat, but some of these mammals escaped from their hutches, multiplied like rabbits, and their populations ran wild. More than 600 million rabbits soon overpopulated the continent, devastating croplands, pastures, and forests with their voracious appetites and penchant for digging burrows. The problem became so great that Australians fought back with every available tool. Early...

Blue Rose Petals and a Mauve Carnation

Wildflower blossoms are magnificent outcomes of the revolutionary dances between plants and their avian and insect pollinators, but they also add great beauty and fragrance to human lives. Not entirely content with nature's designs, however, for centuries horticulturists have crossed and artificially selected many plant varieties for improved showiness and bouquet. Still not content, in the last decade a growing cadre of plant scientists has begun to use molecular genetic techniques to compose...

Daughterless Carp

Terrestrial creatures like rabbits and mice aren't the only invaders plaguing Australia (see previous essay). The continent's aquatic habitats are polluted with unwanted foreigners as well. The European carp, Cyprinus carpio, was introduced into Australian waters more than a century ago. These piglike fish went hog wild, especially in the Murray-Darling River Basin (Australia's largest), where they now account for as much as 90 of the total fish biomass and reach densities of one adult per...

Pesticide Detoxification

The chemical pesticides that humans have developed and deployed over the years sometimes come back to haunt us. A classic case involved the first-ever synthetic insecticide, the organochlorine DDT, that later was banned in the United States. This happened as DDT's devastating ecological impacts and hazards to animal health, including that of humans, became apparent (see chapter 4). The organophosphate insecticides that soon followed, although effective insect killers, had some serious...

Fat Sexy Salmon

In the early 1990s, biotechnologists astounded the world by genetically altering experimental coho salmon so that they grew many times faster than their wild relatives. A famous 1994 picture in the journal Nature showed five of these GM salmon lined up with five of their non-GM brethren, all at 14 months of age and reared under identical conditions. The contrast was startling. The transgenics were veritable behemoths, monsters weighing as much as 37-fold more than their puny nontransgenic...

The Flavr Savr Tomato

In May 1994, consumers were introduced to genetic engineering's first ready-to-eat produce the Flavr Savr tomato. The FDA had just ruled that the two extra pieces of recombinant DNA that Calgene Inc. had manipulated into this cultivar posed no appreciable health risks, so these GM tomatoes were as safe for human consumption as their nonengineered cousins. Actually, the FDA was not obliged by law or policy to pass premarket judgment on these plants. Rather, Calgene (later purchased by Monsanto)...

Combating Corn Borers

Chemical insecticides in agriculture have a tarnished history, despite their promotion as magic bullets by some commercial manufacturers. In 1948, Paul M ller won a Nobel Prize for his 1939 discovery that DDT killed insects, and in the 1950s this and other synthetic toxins saw their first widespread deployment to control agricultural pests. The initial euphoria was misguided, however, as the destructive ecological effects of this broad-spectrum neurotoxin eventually became too great to ignore....

Sperm Whale Oils and Jojoba Waxes

Moby-Dick, the gigantic sperm whale sought by Captain Ahab in Herman Melville's 1851 novel, was merely one of its kind under human assault. From relentless hunting across two centuries, numbers of this endangered species (Physeter catodon) plummeted from many millions in the world's oceans to fewer than 10,000 individuals today. In the 1980s, the International Whaling Commission (IWC) finally imposed an indefinite moratorium on the commercial hunting of many declining cetacean species, sperm...

Microbiological Terrorism

During World War II and the next two decades, in the age before genetic engineering, scientists at the U.S. Army Medical Research Institute of Infectious Diseases (USAMRIID) at Fort Detrick, Maryland, clandestinely researched biological agents that in principle could far surpass the killing power of the most potent traditional weapons. So too did scientists in the former Soviet Union and at least a dozen other countries. No program was larger than that of the USSR's Biopreparat Agency, where...

Tissue Therapy via Therapeutic Cloning

More than 40 years have elapsed since Joseph Murray and his colleagues at a Boston hospital successfully transplanted a kidney between identical twins. This landmark approach was later extended by the medical community to other organs (e.g., heart, liver, lung, and pancreas) and to transplants involving more distant relatives and unrelated individuals. Transplants between unrelated individuals are especially challenging because, unless ameliorative actions are taken, the immune system of a...

Plantibiotics and Pharmaceutical Farming

If transgenic plants can be engineered to produce microbial proteins usable as animal vaccines, could they also be genetically modified to produce human proteins of pharmaceutical or medical value This question has not escaped the attention of biotechnologists. One of the earliest of such attempts was reported in 1997, when researchers isolated the genes specifying human hemoglobin (the oxygen-carrying protein in blood), inserted the genes into a bacterial vector, and then used the microbe to...