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Analysis of rDNA variation in the genus Didelphis (Marsupialia)

Luiz Antônio F. da Silva^I; Miguel A.M. Moreira^II,III; Jurce P. Bezerra^I; Francisco J. Tovar^II; Carlos Alberto S. Almeida^II,III; Regina A. Menezes^II; Orílio Leoncini^II

^IUniversidade Federal de Alagoas, Maceió, AL, Brasil
^IIDepartamento de Genética, Instituto de Biologia, Universidade Federal do Rio de Janeiro, Caixa Postal 68011, 21944-970 Rio de Janeiro, RJ, Brasil. Send correspondence to O.L.
^IIIInstituto Nacional do Câncer/Fundação Ary Frauzino, Rio de Janeiro, RJ, Brasil

ABSTRACT

The 18S and 28S rDNA regions from Didelphis aurita and D. albiventris were analyzed by using restriction endonucleases and hybridizations with 18S and 28S probes. The rDNA regions of D. aurita were cloned and analyzed by physical mapping. Mammalian conserved restriction sites were found. Variation between the two species in the restriction sites allocation were described in the intergenic spacer. Intraindividual variation between the repeat units was not found. A BamHI restriction site not described in other mammals was found in the two species.

Keywords: rDNA; Didelphis.

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