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

摘要: The expansion of amino acid repeats is determined by a high mutation rate and can be increased or limited selection. It has been suggested that recent expansions could associated with the potential adaptation to new environments. In this work, we quantify strength association, as well contribution confounding factors. Mammalian positively selected genes have accumulated more than other mammalian genes. However, found little support for an accelerated evolutionary main driver repeats. most significant predictors are gene function GC content. There no correlation expression level. Our analyses show repeat causally independent from protein adaptive evolution in genomes. Relaxed purifying selection positive do not associate Their occurrence slightly favoured sequence context but mainly molecular gene.