Phylogenetic studies of pantherine cats (Felidae) based on multiple genes, with novel application of nuclear β-fibrinogen intron 7 to carnivores

The pantherine lineage of the cat family Felidae (order: Carnivora) includes five big cats of genus Panthera and a great many midsized cats known worldwide. Presumably because of their recent and rapid radiation, the evolutionary relationship among pantherines remains ambiguous. We provide an independent assessment of the evolutionary history of pantherine lineage using two complete mitochondrial (mt) genes (ND2 and ND4) and the nuclear β-fibrinogen intron 7 gene, whose utility in carnivoran phylogeny was first explored. The available four mt (ND5, cytb, 12S, and 16SrRNA) and two nuclear (IRBP and TTR) sequence loci were also combined to reconstruct phylogeny of 14 closely related cat species. Our analyses of combined mt data (six genes; ≈3750 bp) and combined mt and nuclear data (nine genes; ≈6500 bp) obtained identical tree topologies, which were well-resolved and strongly supported for almost all nodes. Monophyly of Panthera genus in pantherine lineage was confirmed and interspecific affinities within this genus revealed a novel branching pattern, with P. tigris diverging first in Panthera genus, followed by P. onca, P. leo, and last two sister species P. pardus and P. uncia. In addition, close association of Neofelis nebulosa to Panthera, the phylogenetic redefinition of Otocolobus manul within the domestic cat group, and the relatedness of Acinonyx jubatus and Puma concolor were all important findings in the resulting phylogenies. The potential utilities of nine different genes for phylogenetic resolution of closely related pantherine species were also evaluated, with special interest in that of the novel nuclear β-fibrinogen intron 7.