Factor maps for amino acid compositions. (A) amino acid composition of alignable regions of KCNA from 15 vertebrate species. (B) Genome-wide amino acid composition for 15 vertebrate species. (C) Correlation of the first factor of the CA of genome-wide amino acid composition with average coding GC level. CA1: the first axis of correspondence analysis. CA2: the second axis of correspondence analysis. Abbreviations for species names: Hs (Homo sapiens), Mm (Mus musculus), Cf (Canis familiaris), Md (Monodelphis domestica), Oa (Ornithorhynchus anatinus), Gg (Gallus gallus), Ac (Anolis carolinensis), Xt (Xenopus tropicalis), Dr (Danio rerio), Tr (Takifugu rubripes), Tn (Tetraodon nigroviridis), Ol (Oryzias latipes), Ga (Gasterosteus aculeatus), Cm (Callorhinchus milii), Pm (Petromyzon marinus).