The term genetically modified (GM), as it is commonly used, refers to the transfer of genes between organisms using a series of laboratory techniques for cloning genes, splicing DNA segments together, and inserting genes into cells. Collectively, these techniques are known as recombinant DNA technology. Other terms used for GM plants or foods derived from them are genetically modified organism (GMO), genetically engineered (GE), bioengineered, and transgenic. 

By: Tayyaba Zafar & Aqeela Saghir. University of agriculture Faisalabad

In 1988, China became the first country to grow a commercial GM crop: tobacco, modified to resist tobacco mosaic virus (Pray 1999). In the United States, the first GM crop was released in 1994: Calgene’s ill-fated “Flavr Savr” tomato, with a gene altered to delay rotting. The first genetically modified plants – antibiotic resistant tobacco and petunias – were produced by three independent research groups in 1983. Scientists in China first commercialized genetically modified tobacco in early 1990s  The area of GM crops in the developing countries in 2016 was 99.6 million ha (54%) while it was 85.5 million ha (46%) in the industrial ones. USA grew 72.9 million ha (representing 39% of the world total area), Brazil (27%), Argentina (13%), Canada (6%), India (6%), Paraguay (2%), Pakistan (2%), China (2%), and South Africa (1%)Some

Bt cropsBT crops are plants genetically engineered (modified) to contain the endospore (or crystal) BT toxin to be resistant to certain insect pests. “Plant Genetic Systems”, in Belgium, was the first company to produce a Bt crop (tobacco) in laboratory in 1985 but the crop was not commercially successful.

Bt corn (maize)Corn is the only BT crop that is commercially produced and sold in five European countries (Spain, Portugal, Romania, the Czech Republic, and Slovenia), and it is used for livestock feed and row material in the starch industry. These countries produce 173 million tons of ensilage maize and 56 million tons of grain maize

Benefits of GM foods

Agronomic benefits 1996–2012 saw an increase of more than 370 million tons of food crops One-seventh of the increased yield is attributed to GM crops in the U.S. To achieve an equal increase in yield as delivered by GM crops, it is estimated that an addition of more than 300 million acres of conventional crops would have been needed.

Economic benefits From 2006 to 2012, the global increase in farm income from GM food had reached $116 billion, almost triple that of previous 10 years. According to the estimation from James and Brookes, about 42% of the economic gain was from the increased yield due to advanced genetics and resistance to pests and weeds. The decreased costs of production (e.g. from reduced pesticide and herbicide usage) contributed the remaining 58 .

Improvement in food processing The GM technology can also be employed to facilitate food processing. A notable achievement is “Flavr Savr” tomatoes. They were produced by the California Company, Calgene, in 1992.

Potential risks of GM

The anxiety among consumers can be attributed to four sources: the difficulty of the scientific community in explaining concisely to the lay public the biological techniques involved; concerns about the improper dissemination of GM foods; and the ethical principles inherent in traditional food processing; the misgivings with regards to the adequacy of evaluation of the GM foods.

Health risks associated with GM foods

 Three major health risks potentially associated with GM foods are: toxicity, allergenicity and genetic hazards. These arise from three potential sources, the inserted gene and their expressed proteins per se, secondary or pleiotropic effects of the products of gene expression, and the possible disruption of natural genes in the manipulated organism.

GM foods-merits and demerits.


GM foods are useful in controlling the occurrence of certain diseases. By modifying the DNA system of these foods, the properties causing allergies are eliminated successfully. These foods grow faster than the foods that are grown traditionally. Probably because of this, the increased productivity provides the population with more food. A normal crop can grow only in specific season or under some favorable climatic conditions. Though the seeds for such foods are quite expensive, their cost of production is reported to be less than that of the traditional crops due to the natural resistance towards pests and insects. This reduces the necessity of exposing GM crops to harmful pesticides and insecticides, making these foods free from chemicals and environment friendly as well.


The biggest threat caused by GM foods is that they can have harmful effects on the human body. It is believed that consumption of these genetically engineered foods can cause the development of diseases which are immune to antibiotics. Besides, as these foods are new inventions, not much is known about their long term effects on human beings. As the health effects are unknown, many people prefer to stay away from these foods. Manufacturers do not mention on the label that foods are developed by genetic manipulation because they think that this would affect their business, which is not a good practice.

 Many religious and cultural communities are against such foods because they see it as an unnatural way of producing foods. Many people are also not comfortable with the idea of transferring animal genes into plants and vice versa. Also, this cross-pollination method can cause damage to other organisms that thrive in the environment

Conclusion: GM crops can mitigate several current challenges in commercial agriculture. Current market trends project them as one of the fastest growing and innovative global industries, which not only benefit growers but also consumers and major country economies The most obvious is that GM crops are now well established and very successful in large areas of the world, particularly the Americas and China, and other European countries are spending heavily in order to catch up with the UK and US in the science. Moreover, GM crops bring about environmental and health benefits.

Authors: Tayyaba Zafar & Aqeela Saghir. University of agriculture Faisalabad