Genetic Engineering

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Genetic Engineering, alteration of an organism's genetic, or hereditary, material to eliminate undesirable characteristics or to produce desirable new ones. Genetic engineering is used to increase plant and animal food production; to help dispose of industrial wastes; and to diagnose disease, improve medical treatment, and produce vaccines and other useful drugs. Included in genetic engineering techniques are the selective breeding of plants and animals, hybridization (reproduction between different strains or species), and recombinant deoxyribonucleic acid (DNA).

Genetic engineering enables scientists to produce clones of cells or organisms that contain the same genes.
  1. Scientists use restriction enzymes to isolate a segment of deoxyribonucleic acid (DNA) that contains a gene of interest—for example, the gene regulating insulin production.
  2. A plasmid removed from a bacterium and treated with the same restriction enzyme binds with the DNA fragment to form a hybrid plasma.
  3. The hybrid plasmid is re-inserted back into the bacterium, where it replicates as part of the cell’s DNA.
  4. A large number of identical daughter cells (clones) can be cultured and their gene products extracted for human use.

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