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Genetic Engineering: 21st Century's
Frontier Science
by Ibrahim B. Syed,
Ph. D.
What is Genetic Engineering? Engineering is the technological manipulation of the objects of the natural world in a way that is perceived to be beneficial to people. Traditionally we used the word in the context of inanimate nature: bridges, railways and machines etc. But the term can be used and is used in the context of biology, namely for bioengineering, i.e. modifying or manipulating living organisms. Another term used in place of the term 'genetic engineering' (GE) is 'biotechnology' (BT). Some people think that 'biotechnology' sounds less emotive, less fearful. How is genetic engineering defined then? As with the term 'gene', it depends upon who is using it and in what context. Genetic engineering refers to a set of technologies that are being used to change the genetic makeup of cells and move genes across species boundaries to produce novel organisms. The techniques involve highly sophisticated manipulations of genetic material and other biologically important chemicals. Genes are the chemical blueprints that determine an organism's traits. Moving genes from one organism to another transfers those traits. Through genetic engineering, organisms are given new combinations of genes -- and therefore new combinations of traits -- which do not occur in nature and, indeed, cannot be developed by natural means. Such an artificial technology is radically different from traditional plant and animal breeding. Researchers have discovered ways to change the inherited shape, form and function of living things by altering their Genetic material. This process is known as GENETIC ENGINEERING (GE). All living cells-plant, animal and human- contain the genetic material DNA (deoxyribo nucleic acid), which determines the attributes of the offspring of all living things. The molecular gene is a definite sequence of bases in the DNA chain which together code for the production of a particular protein. By directly manipulating the DNA, scientists can change inherited characteristics in predetermined ways. Here the term 'genetic engineering' (GE) shall mean 'transgenesis' or 'recombinant DNA technology', -- i.e. the technology of copying pieces of genetic code from one organism of the same or different species to another by means of the techniques of the molecular biology laboratory. It results in a 'genetically modified organism' (GMO). Genetic engineering is sometimes described as 'modern biotechnology', 'gene technology', 'genetic modification' (GM), 'genetic manipulation' or 'genetic mutilation'. Gene replacement is essentially transplantation surgery although at the molecular level. Cloning is a branch of Genetic Engineering.
Nature can produce organisms with new gene combinations through sexual reproduction. For example cows must breed with other cows (or very near relatives). A breeder who wants a purple cow would be able to breed toward one only if the necessary purple genes were available somewhere in a cow or a near relative to cows. A genetic engineer has no such restriction. If purple genes are available anywhere in nature -- in a sea urchin or an iris -- those genes could be used in attempts to produce purple cows. This unprecedented ability to shuffle genes means that genetic engineers can concoct gene combinations that would never be found in nature.
Genetic Engineering has particularly captivated protracted discussions amongst
Ulema (Islamic scholars) because of a phrase in the Quran about "changing God's
creation." According to the Quran, after Shaitan tempted Adam (AS) and Hawwa
(AS) ( Eve) to sin by eating from the forbidden tree, he was appalled to see
them repenting and being forgiven and honored by their mission to planet Earth
as Allah (SWT)'s Khalifa (vicegerent). Shaitan asked Allah (SWT) to grant him
another occasion to prove that humans are not that trustworthy after all. If
allowed to test them on earth, Shaitan disclosed some of his plots to astound
them saying: "Verily of Thy servants I shall most certainly take my due share,
and shall lead them astray and fill them with vain desires. And I shall ORDER
them so that they cut off the ears of cattle (in idolatrous sacrifice), and I
shall order them to deface the (fair) nature created by GOD." (4:119).
A. Yusuf Ali in his commentary no. 631 says " To deface the (fair) nature
created by God: there is both a physical and a spiritual meaning. We see many
kinds of defacements practiced on men and animals. Against their true nature as
created by God, partly on account of superstition, partly on account of
selfishness. Spiritually the case is even worse. How many natures are dwarfed
or starved and turned from their original instincts by cruel superstitions or
customs? God created man pure: the Evil One faces the image. " The regard for
this verse among Islamic scholars and physicians and health practitioners also
affects their decisions on such issues as plastic surgery, gender transformation
(sexual conversion) operations. Fortunately, however, the consensus is that this
Quranic verse cannot be invoked as a total and radical ban on genetic
engineering. If carried too far it would conflict with many forms of curative
surgery that also entails some change in God's creation. MAIN CONCERNS Many previous technologies have proved to have adverse effects unexpected by their developers. DDT, for example, turned out to accumulate in fish and thin the shells of fish-eating birds like eagles and ospreys. And chlorofluorocarbons turned out to float into the upper atmosphere and destroy ozone, a chemical that shields the earth from dangerous radiation. What harmful effects might turn out to be associated with the use or release of genetically engineered organisms? The answer depends on understanding complex biological and ecological systems. So far, scientists know of no generic harms associated with genetically engineered organisms. For example, it is not true that all genetically engineered foods are toxic or that all released-engineered organisms are likely to proliferate in the environment. But specific engineered organisms may be harmful by virtue of the novel gene combinations they possess. This means that the risks of genetically engineered organisms must be assessed case by case and that these risks can differ greatly from one gene-organism combination to another. Many ethical issues are raised by scientific development of genetic engineering. The creation of new virulent bacteria for use in biological warfare was a serious concern of the early seventies when the technology of recombinant DNA was first described. This type of destructive application is clearly wrong and unacceptable from the Islamic perspective. On the other hand applications such as the diagnosis, correction, cure or prevention of genetic disease are acceptable and even commendable. Potential Harms to Health Here are the some examples of the potential adverse effects of genetically engineered organisms may have on human health. Most of these examples are associated with the growth and consumption of genetically engineered crops. Different risks would be associated with genetically engineered animals and, like the risks associated with plants, would depend largely on the new traits introduced into the organism.
Transgenic crops could bring new allergens into foods that sensitive individuals would not know to avoid. An example is transferring the gene for one of the many allergenic proteins found in milk into vegetables like carrots. Mothers who know to avoid giving their sensitive children milk would not know to avoid giving them transgenic carrots containing milk proteins. The problem is unique to genetic engineering because it alone can transfer proteins across species boundaries into completely unrelated organisms. Genetic engineering routinely moves proteins into the food supply from organisms that have never been consumed as foods. Some of those proteins could be food allergens, since virtually all known food allergens are proteins. Recent research substantiates concerns about genetic engineering rendering previously safe foods allergenic. A study by scientists at the University of Nebraska shows that soybeans genetically engineered to contain Brazil-nut proteins cause reactions in individuals allergic to Brazil nuts. Scientists have limited ability to predict whether a particular protein will be a food allergen, if consumed by humans. The only sure way to determine whether protein will be an allergen is through experience. Thus importing proteins, particularly from nonfood sources, is a gamble with respect to their allergenicity.
Most genetically engineered plant foods carry fully functioning antibiotic-resistance genes. The presence of antibiotic-resistance genes in foods could have two harmful effects. First, eating these foods could reduce the effectiveness of antibiotics to fight disease when these antibiotics are taken with meals. Secondly, the resistance genes could be transferred to human or animal pathogens, making them impervious to antibiotics. If transfer were to occur, it could aggravate the already serious health problem of antibiotic-resistant disease organisms. Although unmediated transfers of genetic material from plants to bacteria are highly unlikely, any possibility that they may occur requires careful scrutiny in light of the seriousness of antibiotic resistance.
Many organisms have the ability to produce toxic substances. For plants, such substances help to defend stationary organisms from the many predators in their environment. In some cases, plants contain inactive pathways leading to toxic substances. Addition of new genetic material through genetic engineering could reactivate these inactive pathways or otherwise increase the levels of toxic substances within the plants. This could happen, for example, if the on/off signals associated with the introduced gene were located on the genome in places where they could turn on the previously inactive genes. Fungal Toxins Although for the most part health risks are the result of the genetic material newly added to organisms, it is also possible for the removal of genes and gene products to cause problems. For example, genetic engineering might be used to produce decaffeinated coffee beans by deleting or turning off genes associated with caffeine production. But caffeine helps protect coffee beans against fungi. Beans that are unable to produce caffeine might be coated with fungi, which can produce toxins. Fungal toxins, such as aflatoxin (a fungal toxin usually found in peanuts), are potent human toxins that can remain active through processes of food preparation. Potential Environmental Harms Monarch butterfly mortality One variety of genetically engineered Corn produced pollen that was toxic to monarch butterflies.. Recent studies reported in Science and Oecologia journals suggested that pollen from the transgenic Bt com may be fatal to monarch butterflies, which feed on milkweed coated with Bt com pollen. Scientists have confirmed the mortality of monarch butterflies exposed to Bt com pollen under both laboratory and field conditions. Proponents of the technology claim that under field conditions the concentration of pollen on milkweed may not reach levels that cause lethal effects. Scientists from Iowa State University are examining this more closely, and their findings should be published soon. A study published in Nature (1999) indicated that secretions from remains of Bt com adversely affected certain other soil borne nontarget insect species. Unnecessary Weeds One
way of thinking generally about the environmental harm that genetically
engineered plants might do is to consider that they might become weeds. Here,
weeds means all plants in places where humans do not want them. In agriculture,
weeds can severely inhibit crop yield. In unmanaged environments, like the
Everglades, invading trees can displace natural flora and upset whole
ecosystems. Some weeds result from the accidental introduction of alien plants,
but many were the result of purposeful introductions for agricultural and
horticultural purposes. Some of the plants intentionally introduced into the
United States that have become serious weeds are Johnson grass, multiflora rose,
and kudzu.. Another example would be a rice plant engineered to be salt-tolerant
that escaped cultivation and invaded nearby marine estuaries. Many insects contain genes that render them susceptible to pesticides. Often these susceptibility genes predominate in natural populations of insects. These genes are a valuable natural resource because they allow pesticides to remain as effective pest-control tools. The more benign the pesticide, the more valuable the genes that make pests susceptible to it. Engineering crop plants, such as tobacco or rice, to produce plastics or pharmaceuticals could endanger mice or deer who consume crop debris left in the fields after harvesting. Fish that have been engineered to contain metal-sequestering proteins (such fish have been suggested as living pollution clean-up devices) could be harmful if consumed by other fish or raccoons.
As with human health risks, it is unlikely that all potential harms to the environment have been identified. Each of the potential harms above is an answer to the question, "Well, what might go wrong?" The answer to that question depends on how well scientists understand the organism and the environment into which it is released. At this point, biology and ecology are too poorly understood to be certain that question has been answered comprehensively. The main concerns about genetic engineering lie in the area of the unknown and unsuspected future. The possibility of grafting new genes not only in somatic cells but also into germ cells thus affecting coming generations, could later be associated with tragic self perpetuating mutations As with any new technology, the full set of risks associated with genetic engineering have almost certainly not been identified. The ability to imagine what might go wrong with a technology is limited by the currently incomplete understanding of physiology, genetics, and nutrition If pursued with man's inclination for seeking the unknown until it is known and the unachievable until it becomes achievable then mankind may be confronted by patterns of life yet to appear on the biological stage. Science might think that everything is under control while the case is not really so. Moral concerns have been voiced that bear on equity, justice and the common good. Perhaps it is time for a comprehensive public debate and the prospective formulation of an ethical code for genetic engineering. A long story is in the waiting, and it is just beginning to unfold! The hazards of nuclear radiation were not apparent for some time, nor could the damage be repaired, and the winnings with genetic engineering are far more serious. The introduction of genetic material from one species into another, in practicality means the creation of a new species with mixed features. Like Adolf Hitler those who support Eugenics (ancestry through inherited characteristics) and elitism could result in discrimination against normal individuals. Thus, manipulating the human progeny might be extended beyond combating disease to the cultivation of certain physical characteristics considered desirable leading to elitism and discrimination against (normal) individuals who lack those characteristics People will be inclined to the abortion of defective fetuses (cystic fibrosis). Tampering with human personality and the manipulation of behavior is possible if genes determining behavior are isolated . . Islam would certainly condemn the principle of tampering with the human personality and its capacity for individual responsibility and accountability. One need to look into sin and abuse of our bodies. The health costs are staggering from alcohol abuse, illegal-drug use, smoking, sexually transmitted diseases and improper diet, not to mention crime and violence as a means to solving problems, "The severing of procreation from sex, love And intimacy is inherently dehumanizing, No matter how good the product" (Ethics of Cloning Humans, Gregory E. Pence, Editor, 1998, p.26). Manufacturing children by cloning could prove to be another step in the further disintegration of the family. In the wrong hands, biotechnology can be a grave danger. At one time nuclear-power plants seemed Like a brilliant idea, but a string of Nuclear-power-plant disasters has dimmed their luster. Worse still is US experiment in which pigs were given human Growth-hormone gene so that the pigs can put on weight faster. They put on weight, but were also partially blind and arthritic and developed Ulcers. BENEFITS: · Animals have been bred to be stronger, more hardy, to produce more wool, milk or meat. On the livestock side, a drug has been produced for dairy cows -- Bovine Growth Hormone (BGH) or Bovine Somatotropin (BST) -- by engineering a bacterium to contain the gene for the hormone. The drug is administered to cows to increase milk production, despite the chronic oversupply of milk in the United States. A highly controversial product when it was first introduced, BGH is currently used on about 10 percent of the US dairy herd. Animals Engineered for Leaner Meat. Animals Engineered as Drug-Production Facilities · Goats and sheep have been engineered to secrete bioactive molecules into their blood, urine, or milk. Companies are in the process developing commercial enterprises based on these animals. So far, none of the drugs is on the market. It is likely that producers will want to slaughter the animals for food after they are no longer useful for drug production. The possibility exists of using animals Engineered as Sources of Transplant Organs Animals Engineered for Disease Resistance. Chickens and turkeys have been engineered to resist avian diseases. None have been commercialized. Genetically Engineered Fish and Shellfish : Fish and shellfish have been engineered to cause changes in hormones that accelerate growth in several laboratories. So far, none have been commercialized in the United States. An engineered predatory mite has been field tested in Florida. Researchers have produced honeybees and other beneficial insects engineered to tolerate pesticides. Bacteria have been genetically engineered to produce rennet, an enzyme important in making cheese. Genetically engineered rennet (chymosin) is approved for commercial use and widely used by US cheese processors. · Strains of wheat, corn and rice have been created that produce more food while needing less fertilizer and water. Genetically engineered crops that were aimed at feeding the hungry, would be developing seeds with certain predictable characteristics: · (a) ability to grow on substandard or marginal soils; · (b) plants able to produce more high-quality protein, with increased per-acre yield, without increasing the need for expensive machinery, chemicals, fertilizers, or water; · (c) they would aim to favour small farms over larger farms; · (d)the seeds would be cheap and freely available without restrictive licensing; and · (e) they would be for crops that feed people, not meat animals.
· Fast-growing trees provide more lumber, Pulp, fuel and shade. Genetically engineered cotton has been approved for commercial use. · Flowers are bigger, more colorful, more beautiful than they would be otherwise. · Several tomatoes engineered to delay ripening have been approved for commercial use. In some cases, delayed ripening just prolongs shelf life that is tomatoes have a longer shelf life. · Rice strains are disease-resistant. Many plants have been commercialized, including tomatoes and squash and commodity crops like corn and soybeans. Most have been engineered for one of three traits: herbicide tolerance, insect resistance, or virus tolerance. · Genes of fish have been placed into potatoes and strawberries to make these plants more resistant to cold weather. · Sheep with skin that will provide immunity to insect parasites.
Plants that produce toxic chemicals that ward off their natural pests. Engineered Microorganisms Used as Pesticides. Several bacteria engineered to enhance their ability to kill or repel pests have been approved for commercial use. These products are used as pesticides in agricultural fields and gardens. · Heal diseases(cancers, diabetes, and Alzheimer's) · Fashion "designer children" and reverse the aging process. Design a customized child who is Genetically disposed to be physically attractive, of superior intelligence or athletically talented. · Eliminating genetic diseases. For example, geneticists think it may be possible to eliminate genetic diseases such as Tay-Sachs through careful and methodical screening programs. · Screening unborn babies. This refers to screening for genetic disorders either before a pregnancy takes place or in the early months of a pregnancy. More information would give prospective parents more options in dealing with their infants’ problems. · Treating diseases. For example, scientists are working on ways to insert cells from embryos into cancerous cells as a way to stop the growth of cancer. · The ultimate beneficiaries of technological innovation have always been consumers, both in the United States and abroad. In developing countries, biotechnological advances will provide means to overcome vitamin deficiencies, to supply vaccines for killer diseases like cholera and malaria, to increase production and protect fragile natural resources, and to grow crops under normally unfavorable conditions. · The pharmaceutical possibilities of genetic engineering will open tremendous vistas in treatment of many illnesses and the possibilities in agriculture and animal husbandry might be the clue to solving the problem of famine the world over.
Conclusion Jimmy Carter, the 39th President of the United States wrote an OP-ED in New York Times of August 26, 1998 titled "Who's Afraid of Genetic Engineering? "….Anti-biotechnology activists argue that genetic engineering is so new that its effects on the environment can't be predicted. This is misleading. In fact, for hundreds of years virtually all food has been improved genetically by plant breeders. Genetically altered antibiotics, vaccines and vitamins have improved our health, while enzyme-containing detergents and oil-eating bacteria have helped to protect the environment. In the past 40 years, farmers worldwide have genetically modified crops to be more nutritious as well as resistant to insects, diseases and herbicides. Scientific techniques developed in the 1980's and commonly referred to as genetic engineering allow us to give plants additional useful genes. Genetically engineered cotton, corn and soybean seeds became available in the United States in 1996, including those planted on my family farm. This growing season, more than one-third of American soybeans and one-fourth of our corn will be genetically modified. The number of acres devoted to genetically engineered crops in Argentina, Canada, Mexico and Australia increased tenfold from 1996 to 1997. The risks of modern genetic engineering have been studied by technical experts at the National Academy of Sciences and World Bank. They concluded that we can predict the environmental effects by reviewing past experiences with those plants and animals produced through selective breeding. None of these products of selective breeding have harmed either the environment or biodiversity. Carter says that by increasing crop yields, genetically modified organisms reduce the constant need to clear more land for growing food. Seeds designed to resist drought and pests are especially useful in tropical countries, where crop losses are often severe. Already, scientists in industrialized nations are working with individuals in developing countries to increase yields of staple crops, to improve the quality of current exports and to diversify economies by creating exports like genetically improved palm oil, which may someday replace gasoline. Other genetically modified organisms covered by the proposed regulations are essential research tools in medical, agricultural and environmental science. If imports like these are regulated unnecessarily, the real losers will be the developing nations. Instead of reaping the benefits of decades of discovery and research, people from Africa and Southeast Asia will remain prisoners of outdated technology. Their countries could suffer greatly for years to come. It is crucial that they reject the propaganda of extremist groups before it is too late. " |
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