ANALYSIS OF RDNA VARIATION IN THE GENUS DIDELPHIS (MARSUPIALIA)

The 18S and 28S rDNA regions from Didelphis aurita and D. albiventris were analyzed by using restriction endonucleases and hybridizations wi th 18S and 28S probes. The rDNA regions of D. aurita were cloned and a nalyzed by physical mapping. Mammalian conserved restriction sites wer e found. Variation between the two species in the restriction sites al location were described in the intergenic spacer. Intraindividual vari ation between the repeat units was not found. A BamHI restriction site not described in other mammals was found in the two species.