With the interpretation of genetic code in 1968 by Hargobind Khorana an Indian born American scientist, for which he receive Nobel prize mere hopes were changed into real approach to gene therapy. The concept of heredity factors in all biological species came from Australian Botanist Gregor Johan Mendel in eighteen eighties. The name gene was given to these factors by Wilhelm Johannesen a Danish biologist. Later research in the field established that genes have many functions. An important one is the formation of large number of proteins. The genes, the scientists say, mastermind the whole process of life in all living creatures. Still it remained a mystery till 1953 when J.D. Watson and Francis Crick discovered the structure of Deoxyribonucleic acid (DNA). DNA is a complex nucleoprotein. It contains body’s 50,000 to 100,000 genes. These genes are arranged in a pattern that is unique to each individual. It is this peculiarity that makes every individual different from the other.
Different genes in different parts of the body have different functions. The gene for a particular purpose is placed at a particular location in the chromosomes. Moreover, the genes play an important role of manufacturing thousands of different proteins from 20 amino acids. The genes, thus govern the immune system too, one can just guess how many problems can be created in the body if any particular gene is broken, is diseased or is removed. Treating, slicing, removing and transplanting the genes is known as Genetic Engineering.
It was formerly a part of science fiction. But with a successful experiment on a four year old girl at National Institute of Health, Bethseda in USA the decoding of the mystery of genes began on September 14,1990. The girl was born with no natural protection against disease as her immune system lacked a particular gene responsible for it. Her blood cell was taken and altered to contain the particular gene, was multiplied and she was injected with one billion of her own blood cells. In another case the doctors altered genes to counteract an affected evil tumor. It is a fatal disease. A cell known as tumor infiltrating lymphocytes was removed and a gene that manufactures a cancer fighter was inserted in it. These cells were reproduced by millions and injected into the patient. The results have been very encouraging.
Researches in different countries in the world have estimated that there are about four thousand disorders because of defects in genes. These may be at the time of birth or may develop in later years. If the researches continue with the same spirit and enthusiasm it is a question of a few decades that Genetic Engineering will replace the conventional treatments in the medical world for the cure of a large number of diseases. John Sulston a lead British Scientist, according to a report of June 21, 2000 has claimed that Human Genome Project provides researchers 97 per cent of the human genetic code. Hundreds of scientists from the USA , Britain, France, Germany, Japan and China are working on the project.