Abstract: The present study examined sequence variations in the Internal Transcribed Spacers (ITS) of nuclear ribosomal DNA (rDNA) among Angiostrongylus cantonensis isolates from Shenzhen, Qingyuan, Jiangmen and Wenzhou in China. The ITS of nuclear rDNA was amplified from individual A. cantonensis by Polymerase Chain Reaction (PCR) and the representative amplicons were cloned and sequenced. The length of the ITS sequences was 1593-1614 bp for all Chinese A. cantonensis specimens and these sequences were composed of complete ITS-1 sequence of 712-720 bp, complete 5.8 S sequence of 153 bp, complete ITS-2 sequence of 633-650 bp and partial 28 S sequence of 70 bp. The intra-specifc sequence variation in A. cantonensis was 0.1-1.0% for ITS-1 and 0.0-1.3% for ITS-2 whereas sequence comparison revealed that the inter-specifc sequence differences were higher: 15.0-34.6% for ITS-1 and 22.7-24.2% for ITS-2 between A. cantonensis and other Angiostrongylus sp. The results showed that the ITS sequences were conserved among the A. cantonensis isolates however, they were quite different from that of other Angiostrongylus species. Therefore, ITS sequences could provide useful genetic markers for the specific identification and genetic characterization of Angiostrongylus sp.
C.Y. Liu, R.L. Zhang, M.X. Chen, J. Li, L. Ai, C.Y. Wu, X.Q. Zhu and R.Q. Lin, 2011. Characterisation of Angiostrongylus cantonensis Isolates from China by Sequences of Internal Transcribed Spacers of Nuclear Ribosomal DNA. Journal of Animal and Veterinary Advances, 10: 593-596.