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Analysis of the rDNA of Chironomus sancticaroli (Diptera, Chironomidae)

Miguel Angelo Martins Moreira; Luiz Antônio Ferreira da Silva; Jurce Portella Bezerra; Orílio Leoncini

Instituto de Biologia, Departamento de Genética, Universidade Federal do Rio dc Janeiro, Caixa Postal 68011, 21944-970 Rio de Janeiro, RJ, Brasil. Send the correspondence to O.L.

ABSTRACT

Chironomus sancticaroli is a South-American chironomid. In order to compare its rDNA with that of other chironomids, genomic DNA was analysed and a rDNA repeat unit was cloned. We compared the data with that from Chironomus thummi (from Europe) and C. lemons (from Europe and North-America). rDNA mits did not show length variation in the repeat units (8.5 Kb). Physical map data showed variation in the 28S coding region, when compared with C. thummi. These small differences are probably related to expansion segments located between conserved regions. New restriction sites for HindIII and HaeIII, in internal transcribed spacer and 28S coding regions, respectively, are reported.

Keywords: rDNA; Chironomus sancticaroli; Diptera.

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