Abstract

Most preferably Codon Preference and Codon biasness refers to same phenomena describing about the usage of synonymous codons. It refers to difference in occurrence of synonymous codons in coding DNA. Codon is a triplet code that codes for a particular type of Amino acid in a polypeptide or it could be a reason for the termination of protein synthesis. There are a total of 20 Amino acids coded by a total of 61 codons, 3 codons are such that does not code any Amino acid but have their importance in termination of polypeptide synthesis during translation.

There are a number of methods used to analyze Codon Preference e.g. methods such as the frequency of optimal codons (Fop) and the codon adaptation index (CAI) are used to predict gene expression levels, while methods such as the effective number of codons (Nc) and Shannon entropy from information theory are used to measure codon usage evenness. Multivariate statistical methods, such as correspondence analysis and principal component analysis, are widely used to analyze variations in codon usage among genes.