Summary: Genome Biology 2005, 6:R67
Open Access2005Haddrillet al.Volume 6, Issue 8, Article R67Research
Patterns of intron sequence evolution in Drosophila are dependent
upon length and GC content
Penelope R Haddrill*, Brian Charlesworth*, Daniel L Halligan* and
Addresses: *Institute of Evolutionary Biology, School of Biological Sciences, University of Edinburgh, Edinburgh EH9 3JT, UK. Section of
Ecology, Behavior and Evolution, Division of Biological Sciences, University of California San Diego, La Jolla, CA 92093, USA.
Correspondence: Penelope R Haddrill. E-mail: firstname.lastname@example.org
© 2005 Haddrill et al.; licensee BioMed Central Ltd.
This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0),
which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
Patterns of intron sequence evolution in !"#$#%&'()
An analysis of inter-specific divergence in 225 intron fragments in Drosophila melanogaster and D. simulans reveals a strongly negative correlation between intron length and divergence and intron divergence and GC content. This suggests thatmost intronic DNA is evolving under considerable constraint.
Background: Introns comprise a large fraction of eukaryotic genomes, yet little is known about
their functional significance. Regulatory elements have been mapped to some introns, though these
are believed to account for only a small fraction of genome wide intronic DNA. No consistent
patterns have emerged from studies that have investigated general levels of evolutionary constraint