Khorana, Har Gobind (1922– )

Indian-born US biochemist who was awarded the Nobel Prize for Physiology or Medicine in 1968 for his part in the interpretation of genetic code and its function in protein synthesis. In 1976 he led the team that first synthesized a biologically active gene. His work provides much of the basis for gene therapy and biotechnology.

Khorana was born in Raipur in the Punjab, now in Pakistan. He studied at Punjab University; in the UK at Liverpool; and in Switzerland at Zürich; returning to the UK in 1950 to work at Cambridge. He has held academic posts in the USA and Canada, becoming professor at the University of Wisconsin in 1962 and at the Massachusetts Institute of Technology in 1970.

Khorana systematically synthesized every possible combination of the genetic signals from the four nucleotides known to be involved in determining the genetic code. He showed that a pattern of three nucleotides, called a triplet, specifies a particular amino acid (the building blocks of proteins). He further discovered that some of the triplets provided punctuation marks in the code, marking the beginning and end points of protein synthesis.

Khorana has also synthesized the gene for bovine rhodopsin, the pigment in the retina responsible for converting light energy into electrical energy.