Biotechnology and its Applications

About this unit

This unit shows how the tools of biotechnology are applied in agriculture, medicine and animal research. It covers genetically modified (GM) crops such as Bt cotton, pest-resistant plants made by RNA interference, the production of human insulin by recombinant DNA technology, gene therapy, molecular diagnosis and transgenic animals. It ends with the social and ethical issues raised by biotechnology: biosafety, patents and biopiracy.

Key ideas

• GM plants can be made more tolerant to stress, less dependent on pesticides and more nutritious.
• Cry genes of Bacillus thuringiensis code for proteins toxic to specific insects.
• RNA interference (RNAi) silences a specific mRNA using double-stranded RNA.
• Recombinant human insulin is made by producing A and B chains separately and joining them.
• Gene therapy corrects a defective gene; the first clinical case was ADA deficiency.
• PCR, ELISA and DNA probes allow early molecular diagnosis.
• GEAC in India regulates GM research and the release of GM organisms.

How to prepare

Memorise which cry genes act against which insects and the steps of the RNAi approach against Meloidogyne incognita. Be clear on why insulin needs C-peptide removal and how ELISA works. Prepare short notes on biopiracy examples and the role of GEAC.