C-mos, a nuclear marker useful for squamate phylogenetic analysis.

Phylogenetic reconstruction in molecular systematics has largely been achieved using mitochondrial gene sequences and less frequently sequences of nuclear ribosomal RNA genes. At present few other nuclear genes have been identified that could be used to test these phylogenies. C-mos, a single-copy nuclear oncogene, has been identified as a candidate nuclear marker. Data are presented on the usefulness of c-mos sequences in the phylogenetic analysis of squamate reptile families. We obtained partial sequences of c-mos from 13 squamate reptile families and outgroup representatives from the orders Rhynchocephalia, Chelonia, and Crocodylia. Phylogenetic analysis reveals a high degree of phylogenetic information contained within the sequence for both the synonymous and nonsynonymous substitutions. Phylogenetic resolution was present at both the deepest and shallower divergences but relationships among the major squamate lineages were not resolved, possibly because rapid cladogenesis may have led to the diversification of these lineages.