Polymerase chain reaction and restriction fragment length polymorphism analysis of the ITS2 region for differatiation of Brazilian Biomphalaria intermediate hosts of the Schistosoma mansoni

Reação em cadeia da polimerase e polimorfismo de tamanho de fragmento de restrição da região do ITS2 para a diferenciação dos moluscos brasileiros do gênero Biomphalaria hospedeiros intermediários do Schistosoma mansoni

We sequenced the internal transcribed spacer 2 of the ribosomal DNA (ITS2-DNAr) from the three Schistosoma mansoni intermediate hosts in Brazil: Biomphalaria glabrata, Biomphalaria tenagophila and Biomphalaria straminea. Analysis of a restriction map from those sequences allowed us to select putative restriction enzymes able to identify the snail species under study. Four restriction enzymes were used and HpaII provided simple species-specific profiles easily visualized in polyacrylamide gels. The use of ITS2 is advantageous as it provides a small fragment of 460 bp which may be easily amplified by PCR. In the current work, we showed that the amplification of ITS2-DNAr together with HpaII enzyme restriction is an auxiliary molecular tool for the morphological identification of such snails as well as for taxonomic and phylogenetic studies of neotropical planorbids.

Biomphalaria glabrata; Biomphalaria tenagophila; Biomphalaria straminea; Polymerase chain reaction; Internal transcribed spacer 2