The expansion of amino-acid repeats is not associated to adaptive evolution in mammalian genes.

ABSTRACT:

Background

The expansion of amino acid repeats is determined by a high mutation rate and can be increased or limited by selection. It has been suggested that recent expansions could be associated with the potential of adaptation to new environments. In this work, we quantify the strength of this association, as well as the contribution of potential confounding factors.

Results

Mammalian positively selected genes have accumulated more recent amino acid repeats than other mammalian genes. However, we found little support for an accelerated evolutionary rate as the main driver for the expansion of amino acid repeats. The most significant predictors of amino acid repeats are gene function and GC content. There is no correlation with expression level.

Conclusions

Our analy

SUBMITTER: Cruz F 

PROVIDER: S-EPMC2806350 | biostudies-literature | 2009 Dec

REPOSITORIES: biostudies-literature