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Divergence and Shannon information in genomes

Hong-Da Chen·Chang-Heng Chang·Li-Ching Hsieh·Hoong-Chien Lee
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Abstract

Shannon information (SI) and its special case, divergence, are defined for a DNA sequence in terms of probabilities of chemical words in the sequence and are computed for a set of complete genomes highly diverse in length and composition. We find the following: SI (but not divergence) is inversely proportional to sequence length for a random sequence but is length-independent for genomes; the genomic SI is always greater and, for shorter words and longer sequences, hundreds to thousands times greater than the SI in a random sequence whose length and composition match those of the genome; genomic SIs appear to have word-length dependent universal values. The universality is inferred to be an evolution footprint of a universal mode for genome growth.

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Hong-Da Chen, Chang-Heng Chang, Li-Ching Hsieh, Hoong-Chien Lee. 2004-12-18. Divergence and Shannon information in genomes. https://doi.org/10.1103/physrevlett.94.178103

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