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

Phylogenetic reconstruction in molecular systematics has largely been achie ved using mitochondrial gene sequences and less frequently sequences of nuc lear ribosomal RNA genes. At present few other nuclear genes have been iden tified that could be used to test these phylogenies. C-mos, a single-copy n uclear oncogene, has been identified as a candidate nuclear marker. Data ar e presented on the usefulness of c-mos sequences in the phylogenetic analys is of squamate reptile families. We obtained partial sequences of cmos 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 b oth the synonymous and nonsynonymous substitutions. Phylogenetic resolution was present at both the deepest and shallower divergences but relationship s among the major squamate lineages were not resolved, possibly because rap id cladogenesis may have led to the diversification of these lineages. (C) 1998 Academic Press.