Introduction to Genes and GM Foods
Genes are made of DNA (deoxyribonucleic acid). A gene is a unit of hereditary material, which carries the required information necessary to produce a protein(s) that determines the characteristics of an organism. Plants and animals, from which foods are derived, have thousands of genes in their cells.
Without knowing the exact mechanism, farmers centuries ago used various traditional breeding methods to produce grains and plants which were bigger, tastier or easier to grow. Nowadays, scientists can identify and modify genes controlling specific characteristics using modern biotechnology. With the help of biotechnology, genes can be inactivated more selectively and precisely, or transferred from one organism to another to produce genetically modified organisms (GMOs).
Any food which is, or is derived from, these genetically modified organisms (GMOs) is called "GM food".
How to make genetically modified crops with a gene coding for a natural pesticide
1. Bacillus thuringiensis is a bacterium that can produce a natural pesticide called Bt protein
The gene coding for the Bt protein
2. The gene coding for the Bt protein is identified and isolated from the bacterium
Plasmid
Recombinant DNA
3. The isolated gene is then combined with a plasmid to form a recombinant DNA by using recombinant DNA techniques
4. The recombinant DNA is put into another species of bacteria for producing more recombinant DNA
5. The bacteria is incubated with plant cell and the recombinant DNA will be transferred from bacteria to plant cells
6. The plant cell develops to a plantlet
Genetically modified plant
7. The new plant is tested for the presence of the natural pesticide – the Bt protein. The production of a genetically modified crops is succeeded if the testing result is positive
Genetic Modification vs Traditional Breeding
GENETIC MODIFICATION | TRADITIONAL BREEDING |
---|---|
|
|
Examples of GM Crops/Foods
GM foods available on the market come in many forms. They are mostly processed foods. The characteristics of the GM foods currently available on the market are similar to their traditional counterparts, except they may have different GM traits, including lower wastage during production and more resistant to herbicides, insects or viral infection. Some examples of GM foods are –
CROP | GM TRAIT | EXAMPLES OF FOOD PRODUCTS |
---|---|---|
SOYA BEAN | Herbicide tolerance | soy beverages, tofu, soy oil, soy flour, emulsifiers (i.e. lecithin), and as ingredients in breads, pastries and edible oil |
CORN | Insect resistance Herbicide tolerance |
corn oil, flour, sugar or syrup, and as ingredients in snacks, bakery, confectionery and soft drinks |
TOMATO | Delay softening of tissue | tomato puree |
POTATO | Insect resistance Virus resistance |
potato chips, mashed potato, potato soups and starch |