GMO foods : What are we eating?

  

GMOs often become the center of debate when the term food insecurity strikes.  GMOs simply stand for genetically modified organisms and are formed via the process of genetic engineering or modification which involves inserting or removing DNA fragments coding the characteristics of interest. Genetic modification does not encompass only plants rather many bacteria species are also genetically engineered to produce many vaccines and hormones. GMOs have been applied more on agriculture sector. Passing of desired and discarding the undesired traits of plants have been practiced since distant past. Conventional breeding involves numerous crossing and the gene combination with the desired traits are selected. Conventional breeding is a hectic program and time consuming too as it is difficult to find the desired combinations among millions. There also remains a possibility of passing of undesired traits along with desired traits while some good traits might not be transferred in the expense of trait of interest. In contrast genetic engineering involves the direct transfer of gene between closely related species thus obtaining the desired traits in the organism.

History                                                                                                              

Sorting out the structure of DNA was the breakthrough and milestone in the field of genetics. Soon many discoveries and findings followed out. It was in 1972 when Paul berg constructed the first recombinant DNA that further paved the path for genetic engineering.  In the year 1973, Herbert Boyer and Stanley Cohen created the first transgenic organism by inserting antibiotic resistance genes in the plasmid of E . Coli.  A Year later Rudolf Jaenisch took the world by storm, when he created the transgenic mouse, inserting foreign DNA into it’s embryo, making it the world’s first transgenic animal. The agriculture field was not indifferent. Several crops were engineered and many field trials were performed. But it was only in 1992, when a tobacco plant genetically engineered to virus resistance was commercialized, after attaining the approval from Chinese government. Since then many agronomic and horticultural crops have been genetically modified to herbicide resistance, pest resistance, disease resistance and to greater yield, nutrition value and longer shelf life. Some of the engineered crops have gained approval for commercial production from the different regulating agencies. While citing their potential hazards and strong opposition from anti GM campaigns some GM crops either have not gained approval or have had their approval rescinded.

What are the prospects of GM crops?

Having said that GMOs are developed via insertion, removal or switching of genes in order to obtain desired characters, the recombined organisms surely do have superior expressions than the parent organisms. World population is increasing geometrically  and is expected to hit about 9 billion in 2050 but the growth in food production is not in accordance with the increasing population i.e is increasing arithmetically. So via proper research and assessment if GMOs are incorporated into the agriculture system, it surely do have the prospect of filling the gap between increment in food and population.

 Aspects on which plants are genetically engineered

·       Enhanced nutrition value

Some crops are genetically modified to have greater nutrition value. Thus we can achieve enhanced nutrition from such crops which can be instrumental in combating with malnutrition.

Fig: normal rice(left) and golden rice(right)

 Golden rice is genetically modified rice and is spliced with three foreign genes. It is modified to bio synthetize beta carotene which is the precursor of vitamin A molecule. The cultivation of golden rice can be a tool to reduce child blindness and deaths which is precarious in African continent.

Similarly Camelina sativa also has been modified to produce plants that accumulate levels of oils similar to fish oils.

Fig ; GM Camelina sativa are engineered to contain omega -3 fish oil

·       Pest resistance in crops

Crops are induced to insect resistance by the incorporation of foreign genes that encodes insect resistant proteins. Especially the genes  of soil bacterium bacillus thuringiensis are inserted to plant. As a result they do produces cry protein which is toxic to caterpillars.

Fig ; comparison of pest destruction between a normal eggplant and a bt eggplant

Bangladesh where the eggplant fields used to be completely devastated by fruit and shoot borer is now making decent progress after the cultivation of Bt eggplant.

 

·       Herbicide tolerant crops

 Weed killing chemicals when applied to field also result in some effect in the major crops. So crops are genetically engineered to be herbicide tolerant and thus applied herbicides destroy the weed prevalent in field without causing any effects in the crops. Many crops in US are engineered to be Glyphosphate tolerant. (Glyphosphate is listed as least hazardous herbicides)

·       Crop protection

The GM crops are also aimed at increased level of protection through the introduction of resistance against plant diseases caused by virus, insects  or fungi.

Fig ; papaya with ringspot caused by papaya ringspot virus

Presently there are many strains of GM papayas engineered to be resistant to papaya ring spot virus which in the past used to devastate the papaya trees specially in Hawai.

·       Plants resistant to adverse climatic conditions

There have been examples from the past where agriculture suffered massive setback when hit by climatic abnormalities such as drought, flood, snowfall etc. So if crops are modified to be resilient enough to such abnormalities, it indeed can be a huge boon to the growers.

If so, what makes GM crops unpopular?

GMOs are the most controversial areas of science. Even though GM insulins are widely accepted, there is a huge prevalency of negative conceptions towards GM crops. There are many anti-GM campaigns advocating the use and consumption of non GM crops. It might seem strange that the field which was scheduled to have trials of GM crops was destroyed by activists group far back in 1983.

Some countries such as US, Canada, China are flexible towards cultivation and commercialization of GM crops and the activities regarding GM crops are governed and regulated by different agencies such as EPA, USDA, and FPA in case of USA. Most of the European countries have imposed strict regulations towards GMOs meanwhile Japan has not approved cultivation of GM crops (except some flowers) but allows import of Products derived from GM crops. Our neighbouring countries have also embraced the cultivation of some GM crops.  India currently only grows only Bt cotton, while china produces GM varieties of cotton, poplar, tomato, cotton etc. Pakistan, Bangladesh, Indonesia have also been approved for commercialization of GM crops.

Majority of people think that GM crops are introduced without proper research. But in most of the cases these are misconceptions. Large no of GM crops have undergone a series of trials , tests and only those which seem not to have any potential hazards are approved.  But as seen in some of the cases ,  it  should not be rushed to be release GM    crops without undergoing series of experiments.

The more concerning aspect is that the possibility of introduction of super weeds via contamination of non GM crops or weed with GM crops. Contamination can also lead to the depletion of biodiversity. Thus it should be ensured that GM crops are properly isolated with non GM crops with proper isolation space. 

There also remains a chance of evolution of bugs making them superbugs against which plants are susceptible. The concept of establishing sewage areas near the GM field might be realistic in order to ward off this possibility.   Insect feed on weeds of sewage areas rather than on resistant crops thus preventing the possibility of developing superbug characteristics.

The most relevant and bugging threat that the GMOs possess is the monopoly of giant bio-tech companies over farmers for seed. The contract signed between the growers and companies prevents farmers from using the saved seeds. These sorts of provisions compel growers of gm crops to make an annual purchase of seeds.

Similarly one study suggested that, the gene contained within BT corn can be harmful to the larva of monarch butterfly when windblown into milkweed leaves. So the effect of such traits on non target organisms also should be properly assessed and evaluated.

The voices surfaced by anti gm activists have been fueled by several  reports highlighting the allergic reactions of GM crops on human and other domesticated animals on the  planet.

In my view GM crops are boon to agriculture. If traits like greater yield, disease and pest resistance, increased nutrition value etc are integrated to the farming system across the whole world, we can change the way we interact with the environment making the world a better place to live. This can be achieved as the use of synthetic chemicals in the form of insecticides, pesticides and fertilizers will get lowered subsequently not triggering any hazards in the environment. More importantly, environment also should not be further deteriorated with the aim of increasing agricultural land in order to feed the growing population. The most positive aspect that GMOs can bring is that it can be a tool to solve the existing precarious condition of malnutrition in poorer countries.

 In a nutshell GMOs are surely the key for ensuring food security and building food sustainability. But it’s potential hazards such as making underdeveloped countries much more vulnerable to external economy, and it’s potential hazards on biodiversity and ecosystem should be properly assessed before approving it for commercial production.