Biotechnology in Agriculture and Health: Notes and PYQs

Biotechnology is the use of living organisms, or parts of them, to make a product or run a process useful to people. Brewing and curd setting are its old forms; the modern subject begins when a gene can be cut out of one organism and put to work in another. Examiners ask this topic from two ends, the farm and the hospital, and they ask the same handful of facts: which organism a gene came from, which enzyme or technique made the transfer possible, and which Indian body clears the result for release.

The branches by colour

Teaching often divides the subject by colour. Green biotechnology is agricultural, red is medical and pharmaceutical, white or grey is industrial, and blue is marine. The tools are common to all of them.

The tools of the trade

Biotechnology on the farm

Plant tissue culture rests on totipotency, the ability of a single plant cell to regenerate a whole plant. A small piece of tissue, the explant, is grown on a sterile nutrient medium, forms an unorganised mass called callus and then whole plantlets, which is how thousands of identical plants are raised from one parent. This is micropropagation, and it is used for banana, sugarcane, orchids and potato. Meristem culture gives virus free planting material even from an infected plant, anther culture gives haploid plants for breeding, and protoplast fusion joins the naked cells of two species into a somatic hybrid, of which the pomato from potato and tomato is the textbook example.

Genetic engineering goes one step further and moves a gene. Bt cotton carries cry genes taken from the soil bacterium Bacillus thuringiensis; the protein they make is harmless as eaten but turns into an active toxin in the alkaline gut of the bollworm, killing it, so the crop needs less insecticide. Bt cotton, approved in 2002, remains the only genetically modified crop cleared for commercial cultivation in India; Bt brinjal was stopped by a moratorium in 2010, and the genetically modified mustard DMH 11 was recommended for environmental release by the regulator in 2022 but has not gone to farmers. Abroad, the Flavr Savr tomato was the first genetically modified food approved for sale, and golden rice was engineered to make beta carotene, the precursor of vitamin A, in the grain. RNA interference has been used to give plants resistance to nematodes.

Not all agricultural biotechnology is transgenic. Biofertilisers use living organisms to enrich the soil: Rhizobium fixes nitrogen in the root nodules of legumes, Azotobacter and Azospirillum fix it while living free in the soil, the blue green alga Anabaena inside the fern Azolla enriches paddy fields, and mycorrhizal fungi help the root absorb phosphorus. Biopesticides include Bacillus thuringiensis itself, the fungus Trichoderma against soil borne disease and the nuclear polyhedrosis virus against caterpillars.

Biotechnology in health

• Recombinant human insulin, marketed as Humulin, was the first recombinant therapeutic protein to reach patients; the two chains of the hormone are produced in bacteria and then joined, so insulin no longer has to be taken from animal pancreas.
• The hepatitis B vaccine was the first recombinant vaccine, made from a surface protein of the virus grown in yeast, so no live virus is used.
• Gene therapy was first attempted in 1990 on a girl with adenosine deaminase deficiency, in which lymphocytes carrying a working copy of the gene were returned to the patient.
• Monoclonal antibodies, made from a single clone of cells, are used both to diagnose and to treat, and they are the basis of many pregnancy and infection test kits.
• Molecular diagnosis finds a disease earlier than symptoms do: PCR detects the genetic material of a virus or bacterium, and reverse transcription PCR is used for viruses whose genetic material is RNA.
• Cloning by somatic cell nuclear transfer produced Dolly the sheep in 1996, the first mammal cloned from an adult cell.
• India developed the world's first DNA plasmid vaccine approved for human use, against Covid, in 2021, and the inactivated vaccine Covaxin was developed by an Indian company with the Indian Council of Medical Research.

Who regulates biotechnology in India

The Department of Biotechnology was set up in 1986 under the Ministry of Science and Technology and funds most of the country's research; the Biotechnology Industry Research Assistance Council, created in 2012, supports industry. Work with genetically engineered organisms is governed by rules framed in 1989 under the Environment (Protection) Act, 1986. Two committees matter for examinations: the Review Committee on Genetic Manipulation, under the Department of Biotechnology, oversees research and small scale trials, while the Genetic Engineering Appraisal Committee, under the Ministry of Environment, Forest and Climate Change, is the apex body that clears the release of a genetically engineered organism into the environment. Access to biological resources and traditional knowledge is governed by the Biological Diversity Act, 2002, administered by the National Biodiversity Authority at Chennai. Internationally, the Cartagena Protocol of 2000 on biosafety and the Nagoya Protocol of 2010 on access and benefit sharing sit under the Convention on Biological Diversity.

Biopiracy and traditional knowledge

India has fought several cases in which its traditional knowledge was patented abroad. A United States patent on the wound healing use of turmeric was revoked in 1997, a European patent on a neem based fungicide was revoked in 2000, and the attempt to claim Basmati rice lines was contested. To prevent such claims, the Council of Scientific and Industrial Research built the Traditional Knowledge Digital Library, which places documented Indian knowledge before patent offices as prior art.

Terms worth keeping straight

• Transgenic organism: one that carries a gene from another species; a genetically modified organism is the wider term.
• Bioreactor and downstream processing: the vessel in which cells are grown in bulk, and the purification and formulation that follow.
• Biofortification: breeding or engineering a crop for higher nutrient content, as in iron rich or vitamin rich varieties.
• Plant breeding: improving varieties by selection and hybridisation rather than by moving a gene directly.