Known organisms on Earth in addition to a few different genetic code are very close; according to the theory of evolution, the genetic code in the history of life very early appeared. The available evidence suggests that the genetic code set is not a random result, and have the following possible explanation:
A recent study showed that some amino acids and their corresponding codons selective chemical binding force, this complex protein manufacturing process may not be early in the morning exists, the original protein may be directly formed nucleic acid. The original genetic code may be much simpler than it is today, to create a new amino acid and then use the genetic code has become complicated with the evolution of life. Although a lot of evidence to prove this point of view, but the detailed process of evolution is still being explored. Through natural selection, that the genetic code to reduce the adverse effects caused by the mutation.
Nirenberg (MWNirenberg, 1927 -) and Matthew (H.Matthaei), to decipher the genetic code first.
The Nirenberg and Matthew vitro protein synthesis technology. They were added to each tube to an amino acid further added to remove the DNA and mRNA in cell extracts, as well as synthetic RNA poly uracil nucleotide results joined tubes phenylalanine multi polyphenylene alanine peptide chain. The experimental results indicate that poly uracil nucleotide led polyphenylalanine synthesis, while the nucleotide sequence of the poly-uracil nucleotide is composed by many uracil (UUUUUUUU. ..... ), shows the nucleotide sequence encoded by the uracil-phenylalanine composed of a peptide chain. Binding Crick derived three bases determine the experimental results in an amino acid, corresponding to the phenylalanine codon should be UUU. In 2067, scientists along the protein synthesis of ideas, and constantly improve the experimental method to decipher all of the codons, and edit the codon table.