Evolutionary determinants of genome-wide nucleotide composition.

ABSTRACT: One of the long-standing mysteries of evolutionary genomics is the source of the wide phylogenetic diversity in genome nucleotide composition (G + C versus A + T), which must be a consequence of interspecific differences in mutation bias, the efficiency of selection for different nucleotides or a combination of the two. We demonstrate that although genomic G + C composition is strongly driven by mutation bias, it is also substantially modified by direct selection and/or as a by-product of biased gene conversion. Moreover, G + C composition at fourfold redundant sites is consistently elevated above the neutral expectation-more so than for any other class of sites.

SUBMITTER: Long H 

PROVIDER: S-EPMC6855595 | biostudies-literature | 2018 Feb

REPOSITORIES: biostudies-literature