Meet HarGobind Khorana: Indian scientist who cracked the Genetic code

Understanding and fighting one of the gravest enemies of humanity — The coronavirus pandemic — could not have been the same had it not been the pioneering work of Professor HarGobind Khorana, who demonstrated the role of nucleotides in protein synthesis and helped crack the genetic code. As the world observed his birth centenary on January 9, humanity is indebted to the Nobel laureate, whose outstanding contribution bagged him the highest accolade in 1968 in Physiology or Medicine along with Marshall Nirenberg and Robert Holley for the elucidation of the genetic code. Khorana has also made significant contributions to the science of Polymerase Chain Reaction (PCR) tests used today to detect the SARS-CoV-2 infection.

Born on January 9, 1922, in Multan in pre-Independence India, his father was a patwari, a village clerk occupying the lowest rung in the agricultural revenue collection system the ruling colonial government set up. Gobind attended Dayanand Anglo-Vedic High School in Multan and completed a Bachelor of Science and a Master of Science fromthe University of Punjab in Lahore. In 1945, Gobind was fortunate to be sent to England on a studentship to study insecticides and fungicides. In Liverpool, Khorana received a PhD in 1948.

Dr Khorana was a man grounded in humility and stuck to principles. He taught us how to be modest except in our aims. In the early 1950s, science was on the cusp of understanding for the first time the exact mechanisms that translate genes into proteins — the central dogma of life. At his first independent job in Vancouver, British Columbia, Gobind began to understand this process.

In 1960, moving to Madison, Wisconsin, Gobind and his colleagues worked hard to solve the problem of the genetic code — how the "language" of DNA and RNA is transformed into proteins in the cell. They were the first to determine the genetic code and show how the nucleic acid bases – Adenine (A), Guanine (G), Uracil (U) and Cytosine (C) – determine the sequence of the 20 different amino acids during protein synthesis. They described the first base "triplet," a set of three nucleotides that make up a codon. The triplet coded for one of the twenty amino acids used to build proteins. There were four bases in RNA,so there were 64 possible codons or triplets in the genetic code.

For many scientists, the Nobel is a lifetime achievement award, but for Gobind, only 46 at the time, it was a rest stop onto even more ambitious projects. Two years after the Nobel, Gobind and his team reported the first chemical synthesis of a gene, coding for a t-RNA. Finally, in the mid-1970s, Gobind — ever-curious, ever-enthusiastic, unable to rest on his laurels — made a complete change in his research career, transitioning to work on biological membranes and light transduction in the photoreceptor cells of the retina.

In 1969, the Indian government awarded him the Padma Vibhushan, the second-highest civilian award. The scientist passed away on November 9, 2011. Upon his death, obituaries across the scientific journals spoke of a scientist "who traversed boundaries", pioneering "concepts and tools from chemistry and physics to tackle the fundamental questions of biology."Dr Khorana and his life would keep inspiring the generations of young scientists.


Khorana Program for Scholars