The Biological Significance of Conserved Nongenic DNA


Although the completion of the human genome was a landmark in genomics, the availability of a single genome did not offer the opportunity to detect most of the functional part of the genome. With the completion of the mouse genome and the subsequent release of additional mammalian and other vertebrate genomes, a large number of conserved nonprotein‐coding sequences were discovered. The most surprising discovery was that the nongenic fraction of the genome that is under purifying selection is larger than the coding fraction of the genome. In this article we review some of the key discoveries in the field and discuss methodologies for the computational and functional interpretation of nongenic deoxyribonucleic acid (DNA).

Keywords: comparative genomics; evolution; non‐coding DNA

Figure 1.

(a) A CNG that is highly conserved across multiple species. (b) A CNG that shows nucleotides of high and low conservations.

Figure 2.

PWM of the MEF2 transcription factor in mammals.

Figure 3.

A region of human chromosome 13 from a UCSC browser view. Two of the tracks show high levels of vertebrate and mammalian conservation in a region devoid of genes.

Figure 4.

Model of a regulatory module with transcription factor binding sites (TFBSs), and the gene they regulate.



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Further Reading

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How to Cite close
Dermitzakis, Emmanouil T(Jul 2008) The Biological Significance of Conserved Nongenic DNA. In: eLS. John Wiley & Sons Ltd, Chichester. [doi: 10.1002/9780470015902.a0020828]