Natural selection shapes genome-wide patterns of copy-number polymorphism in Drosophila melanogaster.
Emerson JJ, Cardoso-Moreira M, Borevitz JO, Long M.
Science. 2008 Jun 20;320(5883):1629-31. Epub 2008 Jun 5.
The role that natural selection plays in governing the locations and
early evolution of copy-number mutations remains largely unexplored. We
used high-density full-genome tiling arrays to create a fine-scale
genomic map of copy-number polymorphisms (CNPs) in Drosophila
melanogaster. We inferred a total of 2658 independent CNPs, 56% of
which overlap genes. These include CNPs that are likely to be under
positive selection, most notably high-frequency duplications
encompassing toxin-response genes. The locations and frequencies of
CNPs are strongly shaped by purifying selection, with deletions under
stronger purifying selection than duplications. Among duplications,
those overlapping exons or introns, as well as those falling on the X
chromosome, seem to be subject to stronger purifying selection.
Click here to know more:
PMID: 18535209 [PubMed - indexed for MEDLINE]