What is Genetic Modification?

Genetic modification involves altering an organism's DNA. This can be done by altering an existing section of DNA, or by adding a new gene altogether. A gene is a code that governs how we appear and what characteristics we have. Like animals, plants have genes too. Genes decide the color of flowers, and how tall a plant can grow. Like people, the characteristics of a plant will be transferred to its children the plant seeds, which grow into new plants. When a scientist genetically modifies a plant, they insert a foreign gene in the plant's own genes. This might be a gene from a bacterium resistant to pesticide, for example. The result is that the plant receives the characteristics held within the genetic code. Consequently, the genetically modified plant also becomes able to withstand pesticides. Not only genetic modification can be used to change animal and plant genes. Spontaneous changes, radiation, chemicals and traditional processing can also alter the characteristics of a plant or animal. Spontaneous alteration of genes takes place naturally and sometimes with no effect. A spontaneous alteration can lead to the development of both positive and negative characteristics. The method is not particularly good if the intention is to create specific changes. Radiation and chemicals can be used in order to effect gene alteration. Both elements are sometimes used in plant processing. With genetic modification it is possible to transfer genes from one species to another. This is because all genes, be they human, plant, animal or bacterial are created from the same material. Genetic scientists therefore have a huge amount of genetic characteristics to choose from.

How does a genetic scientist work?

Genetic modification of plants occurs in several stages:

1. An organism that has the desired characteristic is identified.
2. The specific gene that produces this characteristic is located and cut out of the plant's DNA.
3. To get the gene into the cells of the plant being modified, the gene needs to be attached to a carrier. A piece of bacterial DNA called a plasmid is joined to the gene to act as the carrier.
4. A type of switch, called a 'promoter', is also included with the combined gene and carrier. This helps make sure the gene works properly when it is put into the plant being modified. Only a small number of cells in the plant being modified will actually take up the new gene. To find out which ones have done so, the carrier package often also includes a marker gene to identify them.
5. The gene package is then inserted back into the bacterium, which is allowed to reproduce to create many copies of the gene package.
6. The gene packages are then transferred into the plant being modified. This is usually done in one of two ways:
   • By attaching the gene packages to tiny particles of gold or tungsten and firing them at high speed into the plant tissue. Gold or tungsten are used because they are chemically inert - in other words, they won't react with their surroundings.
   • Byusing a soil bacterium, called Agrobacterium tumefaciens, to take it in when it infects the plant tissue. The gene packages are put into A. tumefaciens, which is modified to make sure it doesn't become active when it is taken into the new plant.
7. The plant tissue that has taken up the genes is then grown into full size GM plants.
8. The GM plants are checked extensively to make sure that the new genes are in them and working, as they should. This is done by growing the whole plants, allowing them to turn to seed, planting the seeds and growing the plant again, while monitoring the gene that has been inserted. This is repeated several times. How do we know if the genetic modification has succeeded? Only rarely can one see whether a plant or animal has been genetically modified, with the naked eye. Scientists have therefore developed some techniques to assist them.

For example:
Special color test can identify whether a plant is genetically modified. When the plant is genetically modified, the scientist inserts an extra marker gene into the plant. The marker gene can have different characteristics, for example, it can make the plant change color when exposed to a chemical test. In this way, scientists can identify whether the plant has been genetically modified or not by performing a chemical test and noting the color of the plant. Altering genes Genetic modification does not always involve moving a gene from one organism to another. Sometimes it means changing how a gene works by 'switching it off' to stop something happening. For example, the gene for softening a fruit could be switched off so that although the fruit ripens in the normal way, it will not soften as quickly. This can be useful because it means that damage is minimized during packing and transportation. Controlling this gene 'switch' may also allow researchers to switch on modified genes in particular parts of a plant, such as the leaves or roots. For example, the genes that give a plant resistance to a pest might only be switched on in the bit of the plant that comes under attack, and not in the part used for food.

For example:

In 2002, researchers at Cornell University in New York used a different scientific approach to develop hardier biotech rice that can resist drought and thrive in marginal soil. In the Cornell study, researchers took the genes that synthesize trehalose, a simple sugar that is produced in a wide variety of plants, including the resurrection plant and inserted them into rice. The resurrection plant is a desert moss that can slow its activity to zero during a drought and completely revive with the return of water. But the University of California Riverside method differs in that no foreign genes were introduced into the tobacco plants to make them drought resistant. Instead, Gallie's research team was able to use the tobacco plant's own genes to reduce the level of the enzyme dehydroascorbate reductase (DHAR), which reduces a plant's ability to recycle vitamin C. And that, in turn, signals the plant to slow the loss of water from its leaves. "This reduction in vitamin C recycling causes plants to be highly responsive to dry growth conditions by reducing the rate of water that escapes from their leaves," said Gallie. "Thus, they are better able to grow with less water and survive a drought.

"Here's how it works...

Plant leaves have tiny pores called stomata that open usually in the morning when it's cooler to allow plants to breathe in carbon dioxide, which they need to grow. In the afternoon, when it's hotter, the stomata close to conserve water. The stomata are controlled by guard cells that open and close the tiny pores based on the level of oxidizers such as hydrogen peroxide, whose level increases when exposed to environmental stresses such as drought. When oxidizer levels rise, the pores close. An antioxidant such as vitamin C destroys these oxidizers in plants. By reducing the vitamin C levels, oxidizers remain high enough to keep the stomata closed. The plant is essentially tricked so it preserves water.

Biotechnology, an evolution of traditional agricultural methods.

Over the past 10,000 years, people have routinely used their knowledge of plants to improve food production. Biotechnology is the latest development in the evolution of agricultural methods. Farmers used to rely on plant breeding to add or eliminate specific genetic traits in a plant. Those with desirable characteristics are selected over several generations. The crops and livestock we see today are a result of traditional processing. For example, because of plant breeding, corn today looks nothing like it did one hundred years ago. Although it typically took several growing seasons to produce a plant that expressed a desired trait, farmers were eventually able to produce crops that were resistant to drought, insect pests or diseases, possessed stronger stalks to withstand strong winds, produced higher yields. Genetic modification is a more efficient and precise way to achieve the benefits of crop improvement. Using new technologies, scientists are now able to pinpoint the specific gene responsible for a particular trait and then extract or add that gene to a specific plant.Genetic modification is a more precise technique, where one can be exact in transferring the desired characteristics. In traditional processing one cannot avoid the possibility that other characteristics may also be transferred. Genetic modification is less time consuming than traditional processing. In traditional processing, characteristics can only be exchanged between species which are the same or very similar. It might be maize and navew or a horse and a donkey. In genetic modification, it's possible to transfer genes from one species to another from plant to plant, from animal to plant, from plant to animal or from animal to animal. This is because all genes, no matter where they come from, are made of the same material DNA.

For example:

How to add a fish gene to a tomato.

Scientists have created a frost resistant tomato plant by adding an antifreeze gene from a coldwater fish to it. The antifreeze gene comes from the coldwater flounder, a fish that can survive in very cold conditions. This is how it was done. The flounder has a gene to make an antifreeze chemical. This is removed from the chromosomes within a flounder cell. The antifreeze DNA is joined onto a piece of DNA called a plasmid. This hybrid DNA, which is a combination of DNA from 2 different sources, is known as recombinant DNA. The recombinant DNA, including the antifreeze gene, is placed in a bacterium. The bacterium is allowed to reproduce many times producing lots of copies of the recombinant DNA. Tomato plant cells are infected with the bacteria. As a result, the antifreeze gene in the plasmid, in the bacteria becomes integrated into the tomato plant cell DNA. Tomato cells are placed in a growth medium that encourages the cells to grow into plants. Tomato plant seedling is planted. This GM tomato plant contains a copy of the flounder antifreeze gene in every one of its cells. The plant is tested to see if the fish gene still works. Is it frost resistant? Yes it is.

Issues related to genetic modification

Some myths related to foods produced using biotechnology:

Myth:

Foods produced using biotechnology has not been established as safe and are not adequately regulated.

Fact:

Biotechnology is one of the most extensively researched and reviewed agricultural developments in our history. The World Health Organization, the US Food and Drug Administration (FDA), the US Department of Agriculture (USDA) and the Environmental Protection Agency (EPA) have all certified the safety of these foods and work together to ensure that crops produced through biotechnology are safe to eat. Governments around the world including Canada, Australia, Singapore, Europe and Japan have reached agreement on the safety of these foods.

Myth:

Crops produced using biotechnology will negatively impact the environment.

Fact:

Biotechnology is an element in sustainable agriculture that will benefit the environment. Benefits include reduced pesticide use, water and soil conservation and greater safety for workers and the ecosystem. Many crops including tomatoes, corn, potatoes and cotton now have the internal ability to repel insects. Consequently, fewer applications of insecticide need to be applied to the plant. A certain type of corn used to feed hogs will reduce the phytic acid in animal waste that traditionally causes algae to grow in water supplies. Finally, the ability to obtain greater crop yield from existing land decreases the need to convert forests to farmland.

Myth:

The production of crops resistant to certain pests and weeds will lead to "Superbugs" and/or "Superweeds" that are immune to existing methods of pest and weed management.

Fact:

There are no scientific studies suggesting this kind of scenario could occur as a result of crops produced using biotechnology. There are, however, many systems in place including crop rotation, hybrid rotation and integrated pest management as a precautionary measure to help prevent it from occurring. Insects and weeds already evolve and develop tolerance or resistance to their environment, so biotechnology can potentially better manage this evolution in resistance.

Myth:

Genetically modified corn kills monarch butterflies.

Fact:

In May 1999, Nature magazine published a letter from researchers at Cornell University that reported findings suggesting further research is needed into the relationship between pollen from select strains of Bt corn (corn which has been genetically modified to produce a protein to protect against insects) and the Monarch caterpillar. Since that publication, many university researchers, including others at Cornell, have stepped forward to stress that the Monarch study did not represent natural conditions and that extensive environmental research has established the safety of Bt corn on non target insects, such as the ladybird beetle, honeybee and the green lacewing, in the natural environment. Dr John Losey, the Cornell University entomology professor who conducted the research, agreed with the researchers and noted, "Our study was conducted in the laboratory and, while it raises an important issue, it would be inappropriate to draw any conclusions about the risk to Monarch populations in the field, based solely on these initial results." As with any scientific issue, several studies are needed before conclusions can be made.

Myth:

Biotechnology cannot relieve world hunger.

Fact:

Biotechnology can help alleviate hunger worldwide. In the next 50 years the global population is expected to double, reaching more than 8 billion people by 2050. Population growth and diet upgrading will require the world food supply to increase at least 250 percent from its current quantity. The amount of land currently committed to food production approximately 36 percent of the earth's cumulative land area cannot yield the amount of food needed by this increased population. Although forests could be cleared to obtain needed acreage, a better approach is to find ways of getting greater crop yield from existing land. Biotechnology can increase the quantity of the harvest by addressing the factors that traditionally deplete crops such as pests, weeds, drought and wind. Plants from biotechnology can deal with these hardships and dramatically increase the percentage of crops that survive and are harvested each year.

Myth:

The long term effects of foods developed using biotechnology are unknown.

Fact:

From years of research, scientists know that the benefits of food biotechnology are enormous. The scientific consensus is that the risks associated with food biotechnology products are fundamentally the same as for other foods. Current science shows that foods produced using biotechnology are safe to consume and a host of regulatory authorities including the US FDA, the United States Department of Agriculture and the US Environmental Protection Agency have determined that these products are safe to introduce into the food supply. While there is no such thing as "zero risk" for any food, consumers can be confident that foods produced using biotechnology meet the same stringent safety standards as foods producing using conventional methods.

FAQs:

Are there safeguards to protect against a new plant variety out crossing to weeds and becoming "out of control"?

Yes there are safeguards against out crossing in the experimental stage. Out crossing is the unintentional breeding of a domestic crop with a related species. Great care is taken to develop new plant varieties that have no weed relatives, do not outcross to weed relatives or whose weed relatives exist only in regions where the domestic crops are not grown. Like traditionally bred plants, a new plant cannot confer its traits on an unrelated plant species.

What if a plant pest such as an insect or a plant disease develops a resistance to a protective trait conferred through plant biotechnology?

Adapting to a changing environment is the natural survival mechanism of all living organisms. Through the natural process of genetic change and adaptation, it is always possible for an insect population or a plant disease strain to build a resistance to a chemical insecticide or fungicide, a protective trait in a plant or to any number of the techniques used to fight plant pests. Nevertheless, to help reduce the potential for resistance development, consideration must be given to resistance management techniques for genetically modified plants. Traditional pesticides have been brought to market for decades without plans in place to delay resistance. By contrast, the development of some of the first genetically modified plants included almost a decade of research to minimize the potential of resistance development. This kind of research had never been done before. The research resulted in strategies to minimize the possibilities of resistance through conscientious programs and carefully chosen genetic traits.

Will antibiotic resistance marker genes make me resistant to the target antibiotics?

No. There is no relationship between an antibiotic resistance marker gene used in plants and antibiotic resistance in humans. The marker gene is used in research to help researchers distinguish a new plant variety from related plants. When the plants are exposed to the target antibiotic in the laboratory, the new plant variety will continue to grow, unaffected by the antibiotic, allowing the researcher to identify and select for plants that have the desired trait. An antibiotic resistance marker gene is not an antibiotic. It produces a protein that allows only plants containing the marker gene to grow in the presence of a specific antibiotic. This protein is broken down in the digestive tract. Therefore, the marker gene product cannot function in the human body. It cannot inactivate antibiotics and the likelihood of an antibiotic resistant gene being transferred from  food to bacteria in the human gut is very small.

There are a few issues, which are relevant to Indian context. These are presented below:

Will GM food reduce hunger in developing countries like India?

If hunger could be addressed by technology, green revolution would have done it long ago. The fact is that hunger has grown in India. In absolute terms, some 320 millions people go to bed hungry every night. Two years back, India had a record food grain surplus of 65 million tones. If 65 million tones surplus could not feed the 320 million hungry, how will GM food remove hunger? In reality, GM food diverts precious financial resources to an irrelevant research, comes with stronger intellectual property rights, and is aimed at strengthening corporate control over agriculture.

But what about malnutrition? Crops like golden rice can help remove blindness.

This again is the result of misplaced thinking. There are 12 million people in India who suffer from Vitamin A deficiency. These people primarily live in food deficit areas or are marginalized. These are people who cannot buy their normal requirement of food, including rice. If they were adequately fed, there would be no malnutrition. If the poor in Kalahandi, for instance, can't buy rice that lies rotting in front of their eyes, how will they buy golden rice?

Then why is the Indian government experimenting with GM crops and foods?

For two reasons: First, India is under tremendous pressure from the biotechnology industry to allow GM crops.These companies have the financial resources to mobilize scientific opinion as well as political support. Second, agricultural scientists are using biotechnology as a Trojan horse. With nothing to show by way of scientific breakthrough in the past three decades, GM research  will ensure livelihood security for the scientists.

What GM crops and food items is India experimenting with?

Besides cotton, genetic engineering experiments are being conducted on maize, mustard, sugarcane, sorghum, pigeonpea, chickpea, rice, tomato, brinjal, potato, banana, papaya, cauliflower, oilseeds, castor, soyabean and medicinal plants. experiments are also underway on several species of fish. In fact, such is the desperation that scientists are trying to insert Bt gene into any crop they can lay their hands on, not knowing whether this is desirable or not.