Abstract: In the present study, a portion of the 18S and 28S ribosomal DNA (rDNA) sequences of 35 Schistosoma japonicum isolates representing three geographical strains from mainland China, the Philippines and Japan were amplified and compared and phylogenetic relationships were also reconstructed by Unweighted Pair-Group Method with Arithmetic averages (UPGMA) using combined 18S and 28S rDNA sequences as well as the corresponding sequences of other species belonging to the Schistosoma genus available in the public database. The results indicated that the partial 18S and 28S rDNA sequences of all S. japonicum isolates were 745 and 618 bp, respectively and displayed low genetic variation among S. japonicum strains and isolates. Phylogenetic analysis revealed that the combined 18S and 28S rDNA sequences were not able to distinguish S. japonicum isolates from three geographical origins but provided an effective molecular marker for the inter-species phylogenetic analysis and differential identification of different Schistosoma species.
F. Chen, J. Li, H. Sugiyama, Y.B. Weng, F.C. Zou, R.Q. Lin, Z.G. Yuan, H.Q. Song, X.Q. Zhu and G.H. Zhao, 2011. Comparative Analysis of 18S and 28S rDNA Sequences of Schistosoma japonicum from Mainland China, the Philippines and Japan. Journal of Animal and Veterinary Advances, 10: 2010-2015.