Deoxyribonucleic acid (DNA) is called the genetic material of an organism that takes part in the heredity. The functional part of a DNA molecule is called as a “gene”.
Genetic engineering is the biological technique developed for changing the genetic code permanently by manipulating the gene. All the biological techniques like fusion, deletion, inversion and transposition of genes are employed here.
Recent advances have been made in the technique for the isolation and joining of unlike pieces of DNA so that biologically active recombinant DNA molecules can be made in vitro. This is called Re-combinant DNA technology.
The discovery of enzymes DNA-restriction end nucleases and plasmids could facilitate the process. For developing recombinant DNA one of these enzymes called restriction enzyme can cut DNA at any specific point required and graft it on a foreign DNA.
Thus recombinant or hybrid DNA is produced. The active recombinant of hybrid DNA can then be introduced into bacteria like E. coliVia, a carrier i.e. a virus called the lamda phase, which preys on bacteria. Thus the hybrids DNA enter into bacterial body. Then E. coil bacterium is broken up by a detergent and the Pisces are spun in a centrifuge to isolate the plasmids.
Plasmid is an autonomous self-replicating extra chromosomal circular DNA. With the help of restriction end nuclease enzyme, the plasmid is cleaved at the specific point. Same enzyme is responsible for snipping off a piece of hybrid-DNA from a virus.
The foreign gene (from the virus) is then inserted into the cleavage of the bacterial plasmid and thus, a recombinant DNA is formed. Next the new hybrid plasmid is introduced into the E. coli bacterium. Now the foreign DNA becomes a part of the bacterium cell. When bacterial cell divides, the hybrid plasmid also divides and multiplies.
Uses of Genetic Engineering:
The recombinanl DNA technology can be utilized successfully for many beneficial applications.
(i) Therapeutic proteins like interferon, insulin, hormones etc, can be produced successfully. Interferon is a powerful antiviral agent developed by body itself. It is highly expensive. With the help of recombinant DNA technology it can be produced plentifully and will be also cheap.
(ii) Production of sufficient insulin and growth hormones, vaccines are also possible. Genetically engineered bacteria have already supplied growth hormones to treat dwarfism and enzyme. Urokinase is used to dissolve blood clots and beta-endorphin, one of brain’s own pain killers.
(iii) BST can be produced by this technique that can boost milk production in cows.
(iv) For protection from diseases, and pests, the crop plants like potato, com, maize, wheat have been endowed with extra genes through genetic engineering.
(v) ‘Nif gene or nitrogen fixing gene can be transferred from leguminous plants to other plants for symbiotic nitrogen fixation, which is now remaining as the monopoly business of the leguminous plants.
(vi) Ultrahigh-yield varieties of staples like rice, wheat, corn etc. are now being designed in agricultural genetic labs, and genetic engineering is ready to generate a second green revolution.
(vii) There is also a chance of creating ‘superior’ human beings through genetic engineering. A day will come genetic engineering will definitely bring a complete revolution in various fields through manipulation of genetic materials.