Send to

Choose Destination
Curr Biol. 2009 Apr 28;19(8):655-60. doi: 10.1016/j.cub.2009.02.039. Epub 2009 Mar 12.

Reduced effectiveness of selection caused by a lack of recombination.

Author information

Institute of Evolutionary Biology, University of Edinburgh, Ashworth Laboratories, Edinburgh, UK.


Genetic recombination associated with sexual reproduction is expected to have important consequences for the effectiveness of natural selection. These effects may be evident within genomes, in the form of contrasting patterns of molecular variation and evolution in regions with different levels of recombination. Previous work reveals patterns that are consistent with a benefit of recombination for adaptation at the level of protein sequence: both positive selection for adaptive variants and purifying selection against deleterious ones appear to be compromised in regions of low recombination [1-11]. Here, we re-examine these patterns by using polymorphism and divergence data from the Drosophila dot chromosome, which has a long history of reduced recombination. To avoid confounding selection and demographic effects, we collected these data from a species with an apparently stable demographic history, Drosophila americana. We find that D. americana dot loci show several signatures of ineffective purifying and positive selection, including an increase in the rate of protein evolution, an increase in protein polymorphism, and a reduction in the proportion of amino acid substitutions attributable to positive selection.

[Indexed for MEDLINE]
Free full text

Supplemental Content

Full text links

Icon for Elsevier Science
Loading ...
Support Center