title: Transthyretin gene (TTR) intron 1 elucidates crocodylian phylogenetic relationships.
abstract: Transthyretin (TTR) is an attractive candidate for use in phylogenetic analysis because it is a short, single-copy nuclear gene with regions that are highly conserved across evolutionarily-divergent organisms from Xenopus laevis to Homo sapiens. To explore its utility as a phylogenetic marker, the complete intron one region (789-805 bp) was sequenced in 22 crocodylian species. Detailed analyses of intron 1 resolved the three expected lineages, Alligatorids, Crocodylids, and Gavialids, and offered additional evidence for the utility of synapomorphic indels in elucidating higher-level phylogenetic relationships. When used in conjunction with other genetic and morphological data sets, intron 1 should be a valuable tool in the investigation of other closely related taxa.
authors.affiliation: Texas Tech University Health Sciences Center, Dept of Cell Physiology and Molecular Biophysics, 3601 4th St MS 6551, Lubbock, TX 79430-6551, USA. raymond.willis@ttuhsc.edu
authors.forename: Ray E
authors.initials: RE
authors.lastname: Willis
mesh_terms: D000489:Alligators and Crocodiles / Q000145:classification / Q000235:genetics*; D000818:Animals; D001483:Base Sequence; D001499:Bayes Theorem; D019143:Evolution, Molecular; D054643:INDEL Mutation; D007438:Introns; D008957:Models, Genetic; D008969:Molecular Sequence Data; D010802:Phylogeny; D011228:Prealbumin / Q000235:genetics*; D016415:Sequence Alignment; D017422:Sequence Analysis, DNA
chemical_list: D011228:Prealbumin