genetic code

Way in which instructions for building proteins, the basic structural molecules of living matter, are ‘written’ in the genetic material DNA. This relationship between the sequence of bases (the subunits in a DNA molecule) and the sequence of amino acids (the subunits of a protein molecule) is the basis of heredity. The code employs codons of three bases each; it is the same in almost all organisms, except for a few minor differences recently discovered in some protozoa.

Following the discovery of the DNA double helix in 1953, which suggested that the sequence of nucleobases along the DNA strand encoded the amino acid sequence of proteins in some way, it took researchers more than a decade to ‘decipher’ the code.