Codon Adaptation Index

The Codon Adaptation Index (CAI)^[1] is the most widespread technique for analyzing codon usage bias. As opposed to other measures of codon usage bias, such as the 'effective number of codons' (Nc), which measure deviation from a uniform bias (null hypothesis), CAI measures the deviation of a given protein coding gene sequence with respect to a reference set of genes. CAI is used as a quantitative method of predicting the level of expression of a gene based on its codon sequence.^[1]

^ ^a ^b Sharp, Paul M.; Li, Wen-Hsiung (1987). "The codon adaptation index-a measure of directional synonymous codon usage bias, and its potential applications". Nucleic Acids Research. 15 (3): 1281–1295. doi:10.1093/nar/15.3.1281. PMC 340524. PMID 3547335.

[SharpLi1987-1] Sharp, Paul M.; Li, Wen-Hsiung (1987). "The codon adaptation index-a measure of directional synonymous codon usage bias, and its potential applications". Nucleic Acids Research. 15 (3): 1281–1295. doi:10.1093/nar/15.3.1281. PMC 340524. PMID 3547335.

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