rnt1

Dr. Hargobind Khorana was responsible for producing the first man-made gene in his laboratory in the early seventies. It was a historic invention which made him famous all over the world. Earlier, in 1968, Khorana shared the Nobel Prize in Physiology or Medicine with M.W. Nirenberg and R.W. Holley. Working independently of one another, all three made contributions to the understanding of the genetic code and how it works in the cell.
Hargobind was born in a village in West Punjab, now in Pakistan, in 1922. Of the hundred people in that tiny village, only those of his family were literate. As a child, Hargobind went to the village school where classes were held in the shade of a big tree.
After doing his M.Sc in Chemistry at the University of Punjab in Lahore, Hargobind went abroad on a government scholarship and took his Ph.D in Organic Chemistry from the University of Liverpool in Britain. As he could not get a suitable job on his return to India, he went back to England for further research.
In 1959, Dr. Khorana, while working at the University of British Columbia in Canada, synthesized a chemical called 'coenzyme A', which is essential for certain processes in the human body. A year later, he moved to the University of Wisconsin in the USA, where he took up the task of building a gene of the bacteria Escherichia coli that lives in the intestines of human beings and animals. Piece by piece, he and his team built up the 'gene' of the bacteria. In August 1976, this man-made gene was 'inserted' into Escherichia coli. It began to work like its natural gene. The achievement was hailed by all, but it had taken several years of consistent labour to produce the artificial gene!

Let us try to understand the mystery of the mechanism of genes.
The word 'gene' comes from the Greek word meaning 'to give birth to'. It is a biological unit which passes on 'hereditary' traits or characteristics from one generation to the next. Genes are passed on from parents to their offspring, so children 'inherit' certain traits of their parents. The study and science of 'heredity' is called genetics.
The serious studies in genetics started around 1860. Gregor Mendel, an Austrian monk, was the first to perform various experiments on pea plants. He noted that in the seeds from parent plants, there were a large number of different factors that always worked by certain rules. He found that some characteristics occur more often than others and he called them 'dominant' characteristics. The others he called 'recessive'.
It was only 16 years after his death, that other scientists saw how important Mendel's findings were. They called his discoveries the Mendelian Laws of Inheritance. Yet, they
did not know exactly how the characteristics are passed from parents to offspring.
All living creatures are made up of many cells. The large dense body in the center of the cell is called the nucleus. Each nucleus contains chromosomes, thin, thread-like bodies made up of DNA, short for 'deoxyribonucleic acid'. A part of DNA is called gene. Several such genes are present in each chromosome. Thus the chromosome of a cell may contain thousands of genes. The gene transmits characteristics from parents to offspring. A single characteristic is controlled by a pair of genes.
DNA is a mixture of sugar and phosphates carrying the genetic information. A model of DNA looks like a rope, twisted into the form of a ladder. Scientists tried to find out how chemical messages or the sequence of the bases along the DNA molecule control cells, the basic units of life.
The secret of the DNA code of life was finally unravelled by Dr. Khorana who showed how the genetic code determines all life processes by directing the synthesis of all cell proteins.
The unravelling of the genetic code has opened the way to a whole new branch of science called 'Genetic Engineering'. Genetic engineering makes possible the creation of new forms of life by altering the genes in DNA. Plant and animal breeders can now produce organisms with almost any mix of characteristics. In 1997, a team of Scottish scientists produced the first live, healthy sheep clone, named Dolly. It is now possible to cure genetic diseases either by repairing the defective gene or introducing normal functioning genes. This has led to novel diagnostic tools for inherited human diseases, as well as for cancer and AIDS.