The New Dictionary of Cultural Literacy, Third Edition. 2002.
genetic code
The code that translates the sequence of nucleotides in genes along the DNA strand into the structure of protein, which, through its action as an enzyme, governs one chemical reaction in the cell. A simple mnemonic is One gene codes for one protein which runs one reaction.
All living things share the same genetic code, a fact that represents strong evidence for evolution. Unraveling the genetic code was one of the great scientific achievements of the twentieth century, and it opened the way to genetic engineering.