GENETIC CODE PROPERTIES

Through the experiments it has been proved that the mRNA codons of the genetic code have the following properties :

The code is triplet : Triplet code consists of 4x4x4 = 66 codons may code for 20 essential amino acids. The triple code of mRNA has been accepted.

The code is degenerate : There are 64 codons in the genetic code for 20 amino acids of which 4 codons are the signals. Therefore, 61 codons are to code for amino acids.It means that more than one codon may be coding for individual amino acid.

The code is non-overlapping : The genetic code is non-overlapping which means that the same letter does not take part in the formation of more than one codon.

The code is non-ambiguous : A particular codon will always code for the same amino acid. It may also be that the same amino acid may be coded by two different codons. However, when one codon codes for two amino acids, it is called ambiguous.

The code is comma less : The genetic code is without comma i.e. no punctuations are required between the two codons. There are no demarcating signals between two codons. This result is continuous coding of amino acid without interruption.No codons are left uncoded.which will be like UUUCUCGUAUCC.

The code has polarity : The code has polarity which is read between the fixed start and stop codons. The start codon is also known as initiation codon, and stop codon as termination codon.

The code is Universal : Though the genetic code has been worked out by using in vitro systems of microorganisms, yet there is no doubt of being its universal for all groups of micro organisms.