Biotechnology in agriculture and health: an overview
Biotechnology serves medicine, diagnosis and farming. Genetically modified organisms have altered genes; GM crops resist stress and pests, waste less and can be more nutritious, like Golden rice.
Where biotechnology is used
Biotechnology now means industrial-scale production of biopharmaceuticals and biologicals using genetically modified microbes, fungi, plants and animals. Its uses include therapeutics (medicines), diagnostics, GM crops, processed food, bioremediation (cleaning pollution with organisms), waste treatment and energy production. Research focuses on three areas. The first is the best catalyst: an improved organism or a pure enzyme. The others are optimal conditions for that catalyst to work, and downstream processing to purify the product.
Why farming needs new options
The Green Revolution tripled the food supply, but this is still not enough for a growing population. The rise came partly from improved varieties and mainly from better management and agrochemicals (fertilisers and pesticides). Agrochemicals are often too costly for farmers in developing countries, and conventional breeding cannot raise yields much further. There are three options: agrochemical-based, organic, and genetically engineered crop-based agriculture. GM crops are one possible solution.
Advantages of genetically modified plants
- More tolerant to abiotic stresses: cold, drought, salt and heat.
- Less reliance on chemical pesticides, through pest-resistant crops.
- Fewer post-harvest losses (less spoilage after harvest).
- More efficient use of minerals by plants, so soil fertility is not used up early.
- Better nutritional value of food, e.g. Golden rice (vitamin A enriched).
- Tailor-made plants that supply starches, fuels and pharmaceuticals to industry.
Biotechnology in health: what this chapter covers
| Area | Example |
|---|---|
| Therapeutics | Human insulin made in E. coli |
| Vaccines | Hepatitis B vaccine made in yeast |
| Stem cell technology | Bone marrow (blood stem cell) transplants |
| Gene therapy | ADA deficiency treated with corrected lymphocytes |
| Molecular diagnosis | PCR, ELISA and DNA probes |
| Transgenic animals | Disease models; Rosie the cow's protein-rich milk |
Why recombinant medicines are better
Recombinant DNA technology allows mass production of safe and more effective drugs. Recombinant therapeutics do not trigger unwanted immune responses, which are common with similar products taken from non-human sources such as animals.
Golden rice was designed for places where rice is the staple food. There, vitamin A deficiency causes night blindness in children, a concern in parts of India too. Bt cotton is the GM crop most Indian farmers know.
3 marks: “List any three advantages of genetically modified plants, with an example.” Tolerance to abiotic stresses (cold, drought, salt, heat); less reliance on chemical pesticides (Bt cotton); fewer post-harvest losses; efficient mineral use; better nutrition (Golden rice, vitamin A).
2 marks: “Name the three options for increasing food production. Why is GM crop-based agriculture being considered?” Agrochemical-based, organic and GM crop-based agriculture. Agrochemicals are costly for many farmers, and conventional breeding cannot raise yields much further.
1 marks: “What is Golden rice?” A GM rice enriched with vitamin A (it makes β-carotene).
GM crop gifts: Some Plants Last More Nutritiously: Stress tolerance, Pest resistance, Less post-harvest loss, Mineral efficiency, Nutrition.